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INTERNATIONAL CONFERENCE

ON NUCLEAR AND RADIOCHEMISTRY (ICNR'86)

Beijing/ China September 1-5, 1986

Co-sponsored by: Chinese Nuclear Society Chinese Chemical Society

In cooperation with China Association For Science And Technology (CAST) CONFERENCE STAFF

Co-Chairmen: S. J. Jiang (MMI) G. T. Seaborg (LBL) Viee-Chaimnan: J. T. Yang (1ST)

International Organizing Ccnmittee (Scientific Progranme Gannittee) Convener: D. X. Wang (IAE) Members: H. J. Ache (Karlsruhe) J. P. Adloif (Strasbourg) A. V. Bellido (Rio de Janeiro) Y. J. Chu (Qinghua U) Y. Y. Chu (BNL) H. R. von Gunten (Bern) D. C. Hoffman (Berkeley) K. H. Lieser (Darmstadt) B. L. Liu (Beijing Normal U) Y. F. Liu (Peking U) B. F. Myasoedov (Moscow) A. W. G. Newton (Manchester) B. D. Pate (Vancouver) T. Tominaga (Tokyo) W. B. Walters (Maryland) A. P. Wolf (BNL)

Advisory Board: S. C. Feng (Academia Sinica) A. Ghiorso (LBL) H. Kakihana (Tokyo) D. G. Liu (Academia Sinica) J. X. Lu (Academia Sinica) R. Y. Qian (Academia Sinica) J. O. Rasmussen (Berkeley) V. Viola (Indiana' A. C. Wahl (St. Louis) J. D. Wang (Qinghua U) Z. K. Wu (MSTI) L. Xiao (IAE)

Local Organizing Conmittee: Chief Convener: Y. F. Liu (Peking U) Conveners: Z. J. Lin (IAE) C. T. Chin (Fudan U) Chief Secretary: H. G. Xu (CMS) Secretary: Z. Y. Zhang (Academia Sinica) \ Members: C. F. Chai (Academia Sinica) Y. T. Jin (Beijing Normal U) X. B. Qiu (CCS) R. H. Tang (Peking U) S. D. Tu (Academia Sinica) Z. Yi Zhang (CNS) K. F. Ju (IAE) Z. Huang (MVfl) D. M. Li (IAE)

MMI: Ministry of Nuclear Industry, Beijing UST: University of Science and Technology, Hefei IAE: Institute of Atomic Energy, Beijing CCS: Chinese Chemical Society, Beijing CNS: Chinese Nuclear Society, Beijing

11 CONTENTS

page Invited Lectures 1. Nuclear Reaction Chemistry

A. M. Poskanzer et al., U.S.A. Relativistic Nuclear Collisions: Compression and Expansion . 1 G. Rudstam, Sweden Isomeric Yields in Nuclear Fission 2 G. Herrmann, F.R. Germany Search for Superheavy Elements 3 F. S. Rowland, U.S.A. Thermal and Energetic Gas Phase Reactions of Radioactive , and Atoms with the Organic Substrates 4 A. G. Maddock, U.K. A Critical Review of Studies of the Effects of Nuclear Changes in Solid Substances 5

2. Actinide Chemistry and Chemistry of Nuclear Fuel Cycle

Wang, De-Xi, China Some Aspects of the Nuclear Fuel Cycle R&D Vfork in China 6 J. D. Navratil, U.S.A. Recent Advances in Processing Chemistry 7 G. Koch. F. R. Germany Trfe Purex Scheme: Ranges of Chemical Parameters 8 M. Pages, France Application of Mossbauer Spectroscopy to Actinide Chemistry ...9 Zheng Qi-Ke, China

Laser Applications in Chemistry of 10

3. Radioanalytical Chemistry

J. Hoste, Belgium Activation Analysis with Charged Particles 11 T. Nozaki, Japan Cyclotron Production of Radioisotopes and Their Use in Other Fields Than Nuclear Medicine 12 I. A. Lebedev et al., USSR Unusual Oxidation States of Transplutonium Elements and Their Use in Analytical Chemistry and Technology 13

ii i Chai, C., China Present Status and Future Perspective of Pile-neutron Activation Analysis in China (a Review) 14

4. Radiopharmaceuticals and Radiolabeled Compounds

G. Stoecklin, F.R. Germany Radiopharmaceutical Chemistry of Radiohalogen Compounds 15 Liu, B. L., China Rapid Exchange Reaction Used for Radiohalogen Label ling of Radiopharmaceuticals 16 A. P. Vfolf, U.S.A. Problems in the Chemistry ot Positron fhutters and .Application to PET Studies in Pathological States 17

5. General Session

M. Sakanoue, Japan Transuranium Nuclides in the Environment 18 R. J. Silva, U.S.A. The Chemical Behavior of Aetinides in Environmental Waters ...19

Discussion Papers

1. Nuclear Reaction Chemistry

J. P. Adloff,et al. Chemical Effects of ot Decay in Uranium Minerals 21 Han H. Y. ,et al. The Kinetic Energy Correlation and the Behavour of Neutron and if-Ray Emission in Ternary Fission of Cf-252 22 V. E. Viola,et al. Nucleosynthesis of the Lightest Elements 23 P." P. Burte, et al. Radiochemical Studies on Fission 24 .K. Aleklett, et al. Unusual Projectile Fragments Formed in Relativistic Heavy Ion Interactions Studied with Nuclear Chemistry Techn i ques 25 Z. Chen, et al. Dependence of Source Radii and Emission Temperatures on Linear Momentum Transfer 26 David J. Morrissey Nuclear Temperature and Excitation 27 William B. Walters The Structure of Odd-Cdd Transitional and Near-Closed-Shell Nuclides 28 iV J. Kopecky, et al- .„_ Isomeric Neutron Capture Cross Section of "'Lu at Stellar Temperatures 29

K. Sakanoto, et al. „ Hq 197 •,•>•> Photospallation Reactions in ° V, °3Y, x"'l and ^^Cs 30 James J. Hogan, et al. Incomplete Fusion in Light Heavy-ion Induced Reactions 31 Sun, T. Y., et al. Recoil Study of Residual Nuclei in the Reaction Induced by 12C on 115In 32 I. Fujiwara, et al. Isotope Yields in ( f" ,7T~xn) Reactions in Ccnplex Nuclei 33 K. Aleklett, et al. Heavy Fragment Production In Intermediate Energy Heavy Ion React ions 34 G. Skarnemark, et al. SISAK - A Technique for Studies of Exotic Nuclides 35

A. TUrler, et al. 4Q „48 Below-Target Yields in the Reactions of Ca + On and 180 + 248Qn 36 R. Korteling, et al. The Study of Complex Nuclear Reactions by Correlating Fragment Emission with Other Particle Emission Using 300 MeV Protons on Be arid Ag » 37 N. T. Porile, et al. Fragment Emission in the Interaction of Xenon with 1-28 GeV/c Protons 38 Arthur C. \Vahl Nuclear-Charge Distribution Near Symmetry for Low-Energy Fission Reactions 39 Yuich Hatsukawa, et al. Decay Properties of Light Isotope (A^247) 40 Fan, W., et al. The Decay of Br 41 R. V. Bogdanov, et al. Three Redox-Forms of Uranium-234 in Britolite 42 N.-K. Wen, et al. g Chemical Effect of Li(n,ot) T Reaction in Conpounds Mixed with Some Compounds 43 Fang, Y. B., et al. Determination and Application Researches of Photonuclear Reaction Yields 44

Hitoshi Shoji, et al. „ 12 „ Recoil Inplantation Behaviours of Be Formed in C(y,na) Be Process in Seme Metal Complex Systems 45 V Y. Watanabe, et al. Studies on the Chemical Effects Associated with BC-decay 57 of Co in Co(III) Complexes Using X,f-ray Coincidence Technique 46 Li, W. X., et al. Charge Distribution in the 14.7 MeV-Neutron-Induced Fission of 232Th: Independent Yields of of Rh, Ag, In and Sb 47 T. Datta, et al. Interaction of Positron with Charge-Transfer Complexes 48 G. Angelini, et al. Gas- and Liquid-Phase Reactions of Nuclear-Decay formed Aryliun Cations with Aromatic Hydrocarbons 49 Hiroshi Baba Fission in A Narrow J-Window and J-Dependent Fission Barriers 50 S. Shibata, et al. Photon-Induced Spallation Reactions of Cu 51 P. Aagaard, et al. Decay Properties and Yield Data of Strongly Neutron-Rich Fission Products 52 Wei-Zhi Tian, et al. Utilization of a Irradiation Vessel for NAA in the 29 37 66 Determination of o~f for Si(n,p), Cl(n,p) and Zn(n,p) React ions 53 H. M. Xu, et al. On Nuclear Temperature Measurements and Feeding from Particle Unbound States 54

2. Actinide Chemistry and Chemistry of Nuclear Fuel Cycle L. Koch, et al\ Alkaline-Anericium-Lanthanide-Separation (ALAS) 56 Takao OI, et al. Theoretical and Experimental Basis for Chemical Enrichment of Uranium Isotopes 57 A. R. Flonbard, et al. The Migration and Sorption Properties of Actinides and Other Radionuclides in Concentrated Salt System Upon Geological Material Taken from A Deep Salt Environment 58 Jess M. Cleveland, et al. Geological Disposal of Actinide-Cbntaining Nuclear Waste: A Chemist's Viewpoint 59 Zheng, Q. K., et al. Luminescence Decay of the Excited Uranyl Ion in Perchloric Acid Solution 60 Vi ttfellace W. Schulz, et al. The THUEX Process: A New Dimension in Management and Disposal of Liquid Tru Wastes 61 H.-J. Bleyl, et al. Activities in and Results of the Improvement of the PLREX Process 62 A. Moccia Progress in New Solvent Development for High Burnup LWt and FBR Fuel Reprocessing 63 L. G. Barreta, et al. Hydrolytic and Radiolytic Degradation of TBP in Systems TBP, 30% (vM-Dodecane^OHN^-TO^NDpo 64 F. David, et al. Physicochemical Properties of 65 Wu, C. C, et al. A Study of the Recovery of Noble Metals and from Reprocessing Wastes of Nuclear Fuel 66 Li Xing-fu, et al. Matching of Coordination Sites with Ligands 67 K. H. Lieser Chemistry of and in the Nuclear Fuel Cycle 68 Chen Yaozhong, et al. Preparation of -242 of Curie Quantity 69 Vera Jedinakotfd, et al. Description of Microamounts of Am(III) Extraction in the Presence of Macroamounts of Lanthanides 70 Heino Nitsche Temperature Effects on the Solubility and Speciation of Selected Actinides 71 Shoichi Tachimori A Mathematical Model of Distribution Ratios for U(IV), U(VI), Pu(III), Pu(IV) and Nitric Acid Between 30 Vol .96 TBP in N.PARAFFIN and Nitric Acid 72 David F. Bowersox, et al. Recent Pyrochemical Research at Los Alamos 73 Zhu Yongjun, et al. The Removal of Actinides from High Level Radioactive Waste by TRPO Extraction—The Extraction of Americiun and Some Lanthanides from Nitric Acid Solutions 74 M. Nounrand Stability Constants of Uranium(VI) and (IV) Complexes with Seme d -Ami no-Ac ids 75 G. Marx, et al. Extraction Phencmena of Np, U, Nd, Ru, Zr and Cr in PUREX- Media Monitored by an Analytical Ultracentrifuge 76 Vii W. W. Sehulz, et al. gg Application of Antimonic Acid to Removal of Sr from Acidic Nuclear \\aste Solutions 77 Yang Dazhu, et al. The Study of Extraction of U(VI) and Pu(IV) by Neutral - Based Organic Compounds , .78 Wfen-j i Wiang, et al. Characteristic and iVfolecular Structure of Extraction Conplex of Uranium(Vl) with Dicyclohexano-18-Crown-6 Isomer A 79 Qin, Q. Z.,-et al. Kinetic Studies on the Extraction of Uranium(VI) from Phosphor\c Acid Solutions with HDEHP and TOPO SO Mao, J. J., et al. The Stability and Absorption Spectra of Uranium( III) in Hydrochloric Acid Solutions .. 81 Chen, Yude, et al. Study of the Ternary Synergistic Extraction of Uranium by Chelate-Chelate-Neutral Extractant 82 Yu, Y. F., et al- Photodissociation of Nitrosyl Nitrates in Nitric Acid Solution '. 83 Tang Jing-juan, et al. Investigation of Absorption Properties of the Silica Gel Impregnated"with Nitrate for Radioiodine 84 Wu, M., et al- Studies on Isotope Shift in IR Spectra and Conplex Effects of a>2Cl2-2TBP 85

Hidetake Kakihana, et al. Chromatographic Chemical Separations of Uranium Isotopes, and Their Fission Criticality with Regard to Nuclear .- Proliferation 86 Yang, M., et al. Interaction Between Photoexcited Uranyl and Sulphate Ions 87 Sun, Z. H., et al. The Precipitation of Pu(III) Oxalate 88 M. Casarci, et al. N,N' DI AlkilAliphatic Amides as Extractants of Actinides: Cur Recent Researcn on the Possibility of Application of These Ccnpounds in Liquid-Liquid Extraction 89 'D. Ertel, et al. PUREX Process Behaviour of Hydrazoic Acid 90 IXian Y. F., et al. Photochemical Reaction in the Aqueous Solution 2+ + Pu(IIl)-Fe -N2H5 -HND3 91

Viii A. M. Koulkes-Pujo, et al. Formation of Reduced Bischlorobis-(Pentemethylcyclo- pentadienyl) Thorium(IV) and UraniundV), by Pulse Radiolysis of Their Solutions in Tetrahydrofuran 92 Fan Xianhua, et al. A. Study on the Behaviour and Restraint of Ru in Pot VJ tr ifi cat ion Process - 93 Lin, C S., et al. Influence of on the Solvent Extraction of from Nitric Acid ...... 94 T. Adachi, et al. Qianicai Properties of Simulated Spent fuel —Dissolution Behavior 95 L. Stieglitz, et al. The Hole of Plutonium in the Degradation of Tributyl- phosphate in the PUREX Process ". 96 Feng-, X. Z. Balance Between Coordination Bond and van der Vfeals Energies of the Coiplex Compounds of Actinides (I) 97 Xu, Y. T., et al. Oniform Packing and Its Prediction on Molecular Structure of Lanthanides and Actinides 98 Guo Ao-ling, et al. "Saturate, Uniform, and Interlocking" in Ligand Packing Structural Characters of Actinide Coordination and Organanetari i c Compounds 99 Wang, W. Q., et al. Synergistic Extraction of Uranyl Perchlorate by the Ternary System of AAC Species Composed of TTA-FMBPr (Cgiy^AsCl 100 Tong Jihong, et al. The Dependence of Uranium(VI) Electro-Reduction Rates on Component Concentrations - ...101 Zhu Yongjun, et al. The Removal of Radioactivity from Oxide 102 Vfeng, S. U., et al. Amidoxime-Polyacrylonitrile Ion-Exchange Fiber and It's Adsorption Behavior for Uranium 103 Choppin, G. R., et al. Thernodynarnic Studies of Curiun Corrplexation 104 Xin, W. D., et al. Investigation on Synergistic Extraction of Uranium with D2EHPA-TRPO-TBP Mixed Extractant from Sulphuric Acid Solution 105

iX Zhao Aimin, et al. Studies on Ion Exchange Equilibria and Kinetics; UO^ ~H~r Cation Exchange Kinetics 106 Huang Haoxin, et al. "Hie Extraction Behavior of RuNO Complexes with r-Irradiated TBP-Kerosene 107 Zhang Qlngxuan, et al. The Investigation on Neptunium Behavior in Electrolytic Partitioning Process of Uranium and Plutonium.. 108 Yu, E. J., et al. An Investigation of the Format ion of A. Third Phase in the Extraction of Plutonium(IV) Nitrate with Tributyl Phosphate .109 D. ML Levins, et al. Leaching of Actinides and Technetium frcm SYNRDC 110 Wang, T. S-, et al. Preparation of U(IV) by Photochemical Process and Degradation Products in Organic Phase of TBP Ill Ge, Q. R., et al. Study on the Kinetics of AtC Thermal Decomposition by Non-Isothermal Method 112 Wu, X., et al. Adsorption Behavior and Isotopic Effect of Uranivm on D318C6-Formaldehyde Condensation Polymer 113 T. Gorgenyi, et al. Production and Characterization of MIR-Fuel Elements with Low Enriched Uranium Using Uraniumsil icide Fuel 114 Zhou, M. L., et al. 211 The Production of At and Its Conplexation with Crown Ethers 115 M. Hussonnois, et al. Preliminary Results about U02 Lixiviation 116 Ling, D. R., et al. On Altering the Lanthanide Chelate Formation Constant Sequence to Improve An-Ln Separations in Cation Exchange Elutions 117 Wu, W. S., et al. Study on Ion Exchange Processes of Uranium and Its Isotopes .118 K. Ollila Parametric Studies of Uranium Solubility in Groundwater 119 Keith W. Fife, et al. Regeneration and Recycle of Spent PuO, Reduction Solvent Salts Used in Pyrochemical Plutonium Recovery Operations at Los Alamos 120 X Chen, Z. D., et al. &-Hydroxy-<*-Methylbutyric Acid A Better Eluent Than of-Hydroxyisobutyric Acid for the Cat ion -Exchange Chromatographic Separation of An(111) and Qn(III) 121 XujGenfu, et al. A Study on the Adsorption Equilibriun of Quaternary Armoniim Resin in Uranyl.Sulphate Solution 122 Ai, H. T., et al. Theory of Kinetics and Equilibriun of Ion Exchange- Adsorption and Mechanism of Extracting Uraniim from Sea-water wi th Ti tanic Gel 123 Xi&, Y. X. Investigation of the Synergistic Extraction of Uranyl Nitrate and Thoriim Nitrate by Mixture of ENHVP+HTTA in -Benzene 124 Qian,, H. S-, et al- Mechanism for the Synergistic Extraction of Uranyl Nitrate by Neutral Phosphorus Extractant (DVHVP) and Acidic Extractants (HDEHP, HEHEHP and HFVBP) 125 Qian, H. S., et al. Synergistic Extraction Mechanism of Thorium Nitrate by Neutral Phosphorus Extractant (DVHV1P) and Acidic Extractant 2-Ethyl Hexyl 2-Ethyl Hexyl Phosphonic Acid (HEHEHP) 126 S. Zouad, et al. Fixation of Radioactive Strontiun on Antimonic and Phosphatoantimonic Acids 127 T. Murcmura, et al. Phase Behavior of Solid Fission Products in UX Fuel 128 Luo Shanggeng, et al. Study on Glass Formulation for Vitrification of HUV wi th High Content of SO^" 129

Tang, B. L., et al. Ligand Exchange and Synergistic Effect in Uranyl Extract ion 130 I. Bayat Determination of Stability Constant of and Trans- Plutoniun Elements with Organic Acid Ion Exchange and Spectrophotometric Techniques 131 Yu Zhi-hui, et al. Complexes of Uranyl Compounds with HVBP and Amides or Phosphine Oxides .-...132

3. Radioanalytical Chemistry

K. Grudpan, et al. A Radiometric Study on Solvent Extraction of Cadmiun Using ALIQUAT-336 134

Xi Yngve Albinsson, et al. On-line Liquid Scintillation Measurements for the AKUFVE Solvent Extraction System 135 Xue, Z. L., et al. Determination of in Biological and Environmental Samples by Pb-203 Radioisotope Dilution Substoi- Chicmetric Method 136 H. B. L. Petterssbn, et al. Radiochemical Determinat ion of Pb-210 137 E7iezer Paul Mignonsin Accuracy of Half-lives Determined by f-R&y Spectrometry 138 Yoshimasa Takashima Measurement of Tritium in Pine Needles and Its Application to Environmental Monitoring 139 M. Sakanoue, et al. Pb-210 and Po-210 in Environmental Samples and Their Behaviours by Smoking 140 V. I. Shamaev New Possibilities of Radioanalytical Chemistry 141 Zhang, Y. H., et al. INAA of Trace Elements in Antarctica Ice Samples 142 A. Chatt, et al. Determination of Trace Elements Through Short-lived Nucl ides Using A SLOWPOKE-2 Reactor 143 Glen E. Gordon Nuclear Analysis of Airborne Particles for Trace Elements —144 G. Revel, et al. Ultra-trace Analysis by Neutron Activation: Application to the Characterization of for solar Use 145 M. Iwamoto, et al. Charged Particle Activation Analysis for surface Under Various Ambient Pressures 146 W. D. Ehmann, et al. Sequential Irradiation Neutron Activation Analysis Applied to the Study of Neurological Diseases 147 F. De Corte, et al. The ^-Standardization Method in (n,

Xii Dong, L. Y., et al. Studies on Determination of Ultratrace-Uraniun in Pyrophosphate Solution by Laser Fluorimetry 151 N. Trautmann, et al. Detection of Trace Amounts of Actinides and Teehnetiim by Resonance Ionization Mass Spectrometry 152 E. A. Hakkila, et al. Some Consideration in Application of Radiochemistry and Non-destructive Assay in IAEA Verification of Materials Accounting in A Nuclear Fuels Reprocessing Plant ..153 T. K. Li A Study of In-line Plutonium Isotopic Analysis for Gaseous Plutonium Hexaf luoride 154 H. H. Starrm, et al. Examination of Radioactive Samples with SBVI and XES 155 Sha, L. M., et al. Radiochemical Analysis of -147 in Diet Food 156 Luo Huanguang, et al. Separation of the Rare Earth, Cd(II), Co(II), Pb(II), Cu(II), Zn(ll), U(VI).and Th(IV) by Thin-layer Chromatography 157 M. D, Glascock Analysis of Boron Using Neutron-capture Garrma Rays 158 M. Ganz, et al. Fast Determination of the Total Amount and Isotopic Compositions of Plutonium Traces in Purified Uranium after Nuclear Fuel Reprocessing 159 V. Verdingh, et al. The Characterization of Uranium and Plutoniim Reference Materials by the (100-X) Route, Basic Principle and Application 160 Wang Yuqi, et al. Determination of Trace Elements and Their Distribution in Soil from the Tianchi Natural Conservation Area by INAA 161 Qian, X. Z., et al. Comparison of Two Preconcentration Techniques for Neutron Activation Analysis of Natural Water 162 Chai, C., et al. Selectivity of Chelating Ion Exchange Resin and Its Application in Searching for Anomaly in Geological Boundries 163 S. Trebert Haeberlin, et al. Application of Neutron Activation Analysis in Dose-activity Relationship Studied on -containing Anti-cancer Drugs ..*.,*,,. = 164

Xiii Tadaharu Tamai, et al. Study on the Chemical Species of Nuclides by A Radio-ion Chromatographic Technique 165 R. Hedvall, et a!. Determination of Pb-210 in Biofuel Ash 166 Tong, C. H., et al. INAA of REE in Uranium Ores and Minerals and Its Application 167 Yi, C. H., et al. A Chromatographic Separation of -211 and an Optimization IVfet hod for the Radioactivi ty Measurement in the Automatic Chromatography Scan System 168 K. Endo, et al. Studies on Energy Transfer in Dioxane-PFO Scintillator Solution with Lifetime Measurement and Pulse Shape Discrimination Technique 169 Zhai Pengji, et al. Trace Uranium Analysis of Various Waters by Fission Track Technique 170 N. R. Das Sequential Separation and Preconcentration of , and Molybdenum from Geological Samples for Neutron Activation Analysis 171 I, Mahadeviah, et al. A Neutron Activation Analysis Study of Water and Sediments in the Mahoning River 172 Ma, S. L., et al. Identification of the Origin of the Magnetic, Silicate and Glass Spherules with Trace Element Abundance 173 Tu, S. D., et al. Neutron Activation Analyses of the Soil Standard Reference Material frcm the Nanjibawa Mountain at Tibet 174 H. Yoshikawa, et al. Radiochemical Techniques: Applied to the Study of Volcanic Gases 175 Kimiko Horiuchi, et al. A New Determination Method of Content in Air Water or Soil by a Liquid Scintillation Counter and Its Applicability in Field Surveying ....? 176 Shiro Iwata, et al. Radiochemical Analysis of Thorium in the Whole Body and Autopsy of Japanese Thorotrast-administered Gases 177

Chen Bingkun, et al. gn Separation and Determination of Sr in Urine with D2EHPA Levextrel Resin 178

XiV Wang Ling, et al- \ Sequential Determination of Isotopes Of U, Th, Ra and Pb in Environmental Water Sarples\ 179 Chen Da, et al. \ Kj. Measurement of 21 Isotopes 1^. 180

Du, H-. Y., et al. \ Determination of Fourteen Rare Eartha, and in Geochemical Standard Reference Sanples by Neutron Activation Analysis \ .181 Mutsuo Koyama, et al. Activation Analysis of Land Plants with Special Reference to the Preferential Uptake of Light or Heavy Rare Earth Elements , \. 182 Nacmi Aota, et al. Neutron Activation Analysis of Di-saggregated Allende Meteorite and of Japanese Geochemical Standard Rocks 183 L. Moens, et al. •Instrumental Neutron Activation Analysis of White Marble 184 M. Skalberg, et al. FENA. - An Improved Method for Epithermal Neutron Activation .Analysis 185 Yang, S. B., et al. Determination of -88 in Gas Fission Products 186 Noriyuki Mcmoshima, et al. A Sensitive Method for the Determination of Tritium in Urine 187 N. Matsuoka, et al. Development of the Apparatus for the Measurement of Krypton-85 and Xe-133 Emergency Situations 188 G. B. Barb, et al. De-iermination of Gamma Impurities in Fission Products Molybdenun-99 189 Yin Hong Qi Determination of Trace Amount of in Drinking Water by Substoichiometric Neutron Activation Analysis 190 Chen Men-an Studies on Polarographic Adsorptive Wave of Uranyl-Cup- ferron Chelate Molecules 191 Cen, Y. H., et al. The Separation of Iron, Thorium, and Uranium with CL-5209 Extraction-containing Resin Column Extraction Chromatography 192

XV Zhang, X- L., et al. Research for Separating Protactinium frcm Uranium and Other Impunities — Extraction-Chromatographic Method Using Quaternary AmTOnium-Kel-F 193 E. Hasanen, et al. Determination of Total Organic Chlorine (TCC1) and (TOBr') in Water Samples by Adsorption onto Activated and Neutron Activat ion Analysis 194 J. Fodor Wear Diagnostics Using f-Ray Spectrometry 195 M. Tsukada, et al. Preconcentration Method for NAA Using an Activable Tracer — Determination of Lathanoid Contents in Various Biological and Geological Standards — 196 Zhuang, G. S., et al. Concentration and Separation of Noble Metals on Chelating Resins for NAA .. 197 Du, H. S., et al. Preparation and Measurement Interccmparison of 241 Standardized Radioactive An Solution 198 Jiang, G. Q., et al. Isotopic Analysis of Hydrogen and Oxygen frcm Antarctic Ice. An Isotope Climatic Variation Record for 5000 Years ...199 Chen, B. R., et al. Determination of Rare Earth Elements in coal Samples frcm 110 Mines in China by INAA 200 Yang, S. J., et al. \ Application of Neutron Activation Analysis in Studying Atmospheric Particulate Matter \. 201 Luo, S. H., et al. \ The Effects of Qing Court Shoutao\Pill on Concentrations of Trace Elements Zn, Cu, Na and ^r in Human Hair 202 Gary M. Sandquist \ Technical Description of Method foA the Quantitative AnalysisofIndividualFissile Concentrations Using Fission Track Count ing \ 203 P. Hoffmann \ Application of Radionuclide Sources for Excitation in Energy-dispersive X-Ray Fluorescence Analysis 204 Bogancs J., et al. Radioanalytical Application of Phosphates at PAKS Nuclear Power Plant 205

4. Radiopharmaceuticals and Radio label led Compounds

XVi N. Vanlic-Razumenic, et al. gg Physico-chemical Characterization of Tc-DPD Conplex - A Bone Imaging Agent. Investigation of the Corp lex Composition 207 Soylu, A., et al. Labeling of Leukocytes with Technetium-99m - 208 B. D. Pate, et al. The Synthesis of Positron-labelled Radiopharmaceuticals for the Study of Movement Di sorders 209

M. Maeda, et al. n Synthesis of Optically Active ( C) Phenylethanolamine Using Qxynitrilase-catalyzed Addition of Hydrogen Cyanide to Benzaldehyde 210

Yao, F. Z., et al. ,5 The Preparation of Carbon Disulfide (CT S2) and Its Derivatives 211 S. K. Shukla, et al. A Study of the Solution Chemistry and Biological Behaviour of -90 for Making It Lesion-specific after Its Administration for Noninvasive Melanoma Therapy 212 Li Maoliang, et al. A New Ster i le In-113m Generator 213 Zhou, Y. G., et al. Synthesis and Biodistributions of Hepatobiliary Imaging Agents Tc-99m(Sn)-PHT, -PHP, -PMT , 214 Liu, B. L., et al. Synthesis and Biodistribution of In-113m-*BAT-TE as A New Myocardial Imaging Agent 215 J. V. Evans Technetium-99m Generation Using An Inorganic Gel 216 R. D. Finn, et al. Cyclotron Preparation of "No Carrier Added" -153 DTPA Radiopharmaceutical 217 Kabalka, G. W., et al. Synthesis of L I-Iodovinylamino Acids via Organoboranes: Potential Yurnor-imaging Agents 218 Sun, S. Y., et al. An Investigation on the Separation of High Specific Activity Mo-99 for Medical Use from Fission Products of U-235 by Means of Column Chromatography 219 Brian F. Abeysekera 1-123 Labelled Radiopharmaceuticals 220 H. Korpela, et al. 18 Preparation of 2- F-Fluoro-2-Deoxy-D-Glucose by Nucleophilic 18 Substitution with Tandem Accelerator Produced F-Fluoride ..221 XVii C.-Y. Shlue, et al. Application of the Nucleophilic Fluorination Reactions to the Synthesis of No-Carrier-Added (NCA) F-Labelled Radiol igands » 222 Zhou, Y. G., et al. An Improved Synthesis of A Bone Imaging Agent Tc-9Gn> HVDT and Its Biodistributions 223 Jin, Y. T., et-al. Preliminary Study on Preparation and Animal Distribution of ^Te2(CO)10 as A New Brain Imaging Agent 224 Liu, B. L., et al. The Studies on Kinetics of Ligand Exchange Reaction between Te-99m-Glucoheptonate and t-Butylisonitrile 225

Lu, J. X-, et al. 123 123 Radiopolarographic Determination of I and Na I 226 S. R. Malik , Dynamics of Deuterium Distribution in Humans Using 7D(f,n) React Ion 227 Shen, D. C., et al. Synthesis of Tritium Labelled Nucleoside Triphosphates by Enzymatic Phosphorylation 228 Chen, S. Z. Study on O-Iodohippurate and Sodium O-Iodohippurate (131I) by HPLC 229 Xue Jiayu, et al. The Preparation and Application of An Iodination Agent for Radiopharmaceutical Synthesis 230 Zhang Xin, et al. Synthesi's of H and C Label led Changrol in 231 Li, Z. M., et al. Primary Study on the Mechanism of Tritium Labelling by Microwave Discharge Method 232 Cao, G. Y., et al. Preparation of Three Kinds of Pesticides Labelled with C-14 or S-35 233 Gu, M. Y., et al. Synthesis of (3-14C) Indirubin 234 Y. Minai, et al. Cyclotron Production of Al-29 and Ti-45 Tracers for Agricultural Studies 235 Y-Z. Guo+, et al. Preparation of [125l] (R)-8-IODO-2,3,4,5- Tetrahydro-3-Methyl-5-Phenyl-lH-3-Benazepine- 7-OL : A Dopamine Specific Imaging Agent 236 XViii Zhang Wenying, et al. Studies of Adsorption, Migration and Persistence of 14 toluene in Soil by Means of C-labelled Ccnpound 237 Ding, VV. D., et al. Reversed-phase High-performance Liquid Chromatographic Investigation on the Relationship between Structure and IN VIVO Distribution of Hepatobiliary Agents 238 Zhu, T., et al. The Preparation and Identification of Tritiun Labelled Agonist and Antagonist of Opiate Receptor 239 Zhuang, D. L., et al. Photosensitized Tririum Labeling of Bio-macromolecule Lect ins 240 JJ Billings, et al. 125 Preparation of ( I) N-(4-Iodophenyl)-N-(l-(2-Phenylethyl))- 4-Piperidinamine: A Fentenyl Analog 241 Tjioe, P. S., et al. The Metabolism of Selenite Injected in Mice and the Influence on It of the Heavy Metal Platinum 242 Wang, C. P., et al. Cyclotron Production of Thallous Chloride Tl Injection ...243 David R. Elmaleh, et al. Preparation of N-( C-Methyl) Chlorphentermine ( C-NVCP) Through Methylat ion of Chlorphentermine Trifluoroacetamide ..244 J. Hiltunen, et al. 1 fc^ 1 f\^ Production of Dy for Dy-Ferric Hydroxide Maeroaggregates 245 Anthony Egan Selection, Application and Analysis of Radiolabelled Ccmpounds in Oil Reservoir Studies 246 R. J. Flanagan, et al. Radiochemical Reactors. A New Type of Generator for the Simple Synthesis of Halogenated Radiopharmaceuticals 247 Lin, Q. F., et al. Preparation of I-131-anti-otFP-IgG of High Radioactivity for Radioirrmunotherapy 248 Yi, M. G., et al. Labelling of A New Chelating Agent (H-73-10) with Tritium and Carbon-14 249 Huang, Y., et al. Labelling of IgG and Monoclonal Antibody with 169Yb and 51Cr 250

XiX 5- General Session

G. Marx, et al. Radiochemical Investigation on Corrosion of Valve Afetals and Stainless Steel under the Influence of Plutonium 252 E. Holm, et al. AetiniJes and Isotopic Ratios in the Greenland and Barents Seas 253 Satoru Nakashima, et al. jMbssbauer Spectroscopic Study on the Mixed-valence States of 1\ 1" *-Dt(Ak thy I benzyl) Bi ferrocenium Tri iodides 254 M. Suzuki, et al. Antiferrcmagnetically Coupled Dinuclear High Spin Iron(II,lII) Mixed Valence Complexes with the Dinucleating Ligand, L-py or L-Bzim 255 H. Feuerstein Behaviour of Radionuclides in Sodiim Cooled Reactors A Review 256 R. T. Lowson, et al. Groundwater Radiocolloids in the Vicinity of Some Australian Uranium Ore Bodies 257 H. H. Stanm, et al. 15 years of Radiochemical Surveillance of the KNK Primary Sodium 258

K. Bachmann, et al. 2„q Radioecological Studies of Pu and Natural Radionuclides ..259 Sheng, H. Y., et al. Studies on Lithium isotope Separation by the Neutral Ligand Synergistic Systems of Arylazo-Beta-Naphthols and Beta-Diketones .*. 260 Fan, W., et al. The Determination of Adsorption Enthalpies of Tl-204 by Isothermal Gas Chromatographic and Thermochromato- graphic Methods 261 M. Yanaga, et al. Studies of the Electronic Charge Distribution in Organo- (V) Compounds by Means of Mbssbauer and NVR Spectroscopy 262 Chien C. Lin Radiochemical Studies in the BWR Primary Coolant System 263 Etienne Roth, et al. Tritium Chemistry in Fission and Fusion Reactors 264 H. Feuerstein, et al. 20 years Chemical and Radiochemical Measurements at the Research Reactor FR2 265 XX Piroska Fodor-Csanyi, et al. Uater Migration Studies in Connection with Radioactive Waste 266 H.-H. Tetzel, et al. Determination of Equilibrium Constants in Solution by Using An Analytical Ultracentrifuge 267 Chr. Binder, et al. Determination of Diffusion Coefficients, Partition Coeffifients and Extraction Kinetics by Use of the Analytical Ultracentrifuge 268 T. Miura, et al. Comparison of Experimental Contact Density of Va\ence Electrons with AD and MD Calculations for Te 269 S. K. Shakshooki, et al. Mixed Insoluble Acid Salts of Tetravelent Metals - IV Crystalline Mixed Zirconium- Phosphates 270 T. Hashimoto, et al. Bnission Properties of Thermoluminesence from Natural Quartz Minerals 271 Kirsti-Liisa Sjoblan, et al. 14 The Escape of 002 into the Laboratory Air During Phytoplankton Primary Production Studies- 272 Huang, Y. P., et al. Radiochemical Studies on Deep-sea Nodules 273 Li Peiquan, et al. The Distributions and Geochemical Studies of U, Th, Ra, 40 K in Sediments of China Sea and Adjacent Sea 274 Michiko Abe, et al. „ Physical and Chemical Behavior of Be in the Atmosphere at Chiba 275 Yuko Saito, et al. 90 137 Sr and Cs in Tree Rings of the Japanese Cedar, CRYPTCMERIA JAPCNICA 276 Masanobu Watababe, et al. Mbssbauer Spectroscopic Studies of Metal Halide Adducts with Ferrocenylruthenocene and Related Compounds 277 K. Heinzinger A Molecular Dynamics Simulation of Liquid T„0 278 C. Ferradini, et al. Ionizing Radiations as a Tool for Study about Mechanisms of Biological Interest: Application to Vitamin E in Alcoholic Medium 279 Wang, R. S., et al. The Adsorption Behavior of Microamount of on Inorganic Ion Exchangers 280 XXi Jerzy Kroh Early Stages of Electron Interaction with Matter- - Mechanism and Kinetics 281 M. M. Bhutani On the Feasibility of Concentration Minute Amounts of Certain Ionic Species by the Adsorption Technique- AKadiotraeer Study 282 M. M. Bhutani. Sorption Behaviour of Radioactive Chrcmate and Phosphate Species on Certain Microcrysta-lline Sulphates by the Radiotracer Technique 283 A. Sial, et al. Recent Developments in the Use of Nuclear Track Filters for Appl i ed Purposes 284 Miassoedova T. G., et.al. 2+ + Solvent Extraction of Sr and Cs with Crown Ether 285 Navratil Oldfich, et al. New Phosphorus Containing Extractants for Separation of Matals 286 Chen Jinxing, et al. The Application of Natural Radiotracer to Study the Transportative Regularity of the Silts in Jiulong River 287 Zhong, G. T., et al. A Principle of Element Dilution 288 H. Feuerstein, et al. Behaviour of UD« and Fissium in Sodium Vapor Atmosphere at Temperatures up to 2850°C 289 J. V. Evans, et al. Geochemistry of Uranium and Daughters in Tailings from the Milling of Uranium Ores 290 M. Put, et al. Seme Aspects of Radiolysis in the Boom Clay Formation 291 Yang Wen-Xiang, et al. Radioactive Tracer Study of the Reaction of HD 14 with CS2 in the Presence of 02 292 Tsou, H. R., et al. The Use of 180 and 13C Labeling in Studies of the Origin of Oxygen Atoms in a Novel Macrolide Antibiotic LL-F28249 293

Author Index 294

XXii A.M. Poskanzer. K.G.R. Doss, H.-A. Gustafsson. H.H. Gutbrod, B- Kolb, H. v_chner, B. Ludeviigt, T. Renner, H. Riedesel, H.G. Ritter, A. Warwick, and H. Wieman Gesellschaft filr Schwerionenforschung, D-6100 Darmstadt, West Germany and Nuclecr Science Division, Lawrence Berkeley Laboratory University of California. Berkeley, California 94720

RELATIVISTIC NUCLEAR COLLISIONS: COMPRESSION AND EXPANSION*

Heavy nuclei, 1n central collisions at relativistic energies, stop 1n their center of mass producing a region of equilibrated, hot matter. Some of the energy 1s stored as potential energy of compression. At the same time the pressure builds up, producing a sldewlse collective flow of nuclear matter. The system then expands until the density is reduced so that the chemical equilibria producing the light composite nuclei freeze-out, and then even further until the thermal two body Interaction freezeout. Each of these points will be documented with recent experimental results from the Plastic Ball and other 4* detectors at the Bevalac.

*TMs work was supported In part by the Director, Office of Energy Research, Division of Nuclear Physics of the Office of High Energy and Nuclear Physics of the U.S. Department of Energy under Contract DE-ACO3-76SF00O98.

- 1 - Gdsta Rudstam The Studsvik Science Research Laboratory, S-611 82 Nykoping, Sweden

ISOMERIC YIELDS IN NUCLEAR FISSION

The distribution of the fission yield between the isomeric states of the fission products Has been relatively little investigated until now, .Largely because of experimental difficulties. Recently, an extensive set of yield data has become available, how/ever, as the result of an experiment Using the OSIRIS facility (isotope separator direct­ ly attached to a 1 MW research reactor). By means of this facility fission products with half-lives of the order of 0.1 s or longer can be.jjtudied. In the experiment a target consisting of " U was irra- iated with thermal neutrons, and isomeric yield Sata were obtained for the following nuclides: Bromine: 84m Krypton: 85m Silver: 113,113m,115,115mt118,118m,120,120m : 119,119m,121,121m :*) 120L,120M,120H,122L,122M,122H,123,123m,124L, 124H,126L,126H,127,127m,128L,128H,129,129m, 130L,130M,130H : 123,123m,125,125m,127,127m,128,128m,129,129m, 130,130m Antimony: 128m,130,130m,132,132m : 133,133m : 134,134m,136,136m Cesium: 138m All this material combined with published results on other nuclides is used for a systematic investi­ gation of how the fission yield is distributed among rhe isomeric states of the fission products. *) L, M, and H, stand for low sgin (1,3 ), medium spin (4,5 ) and high spin (8,10 ) states of even- mass indium isotopes.

- 2 - Giinter Herrmann Institut fur Kernchemie. Universitat Mainz, and GeseTTschaft fur Schwerionenforschung, Darmstadt, Fed. Rep. of Germany

SEARCH FOR SUPERHEAVY ELEMENTS

A review will be presented on recent attempts to produce superheavy elements located around atomic number 114 by heavy-ion reactions at the Darmstadt heavy-ion accelerator UNILAC. Two approaches were followed: (i) Transfer of nucleons between two very heavy nuclei, such as 2g®U and 2g®U or 2^U and 2ggCni; (ii) fusion of ^Ca with gcCm. A variety of techniques was used for the isolation of superheavy nuclei, including chemical separations off- and on-»line and separations in magnetic and electric fields. Extremely sensitive detection techniques for spontaneous fission events were applied in order to extend the search experiments to a production rate of a few atoms per day. The experiments remained negative. In the most 48 248 thorough study, on the Ca + Cm reaction, a half-life range from -34 -35 2 1 ps to 10 yr was covered at an upper limit of 10 to 10 cm for the production cross section.

In another major research project at the UNILAC three new elements, 54 58 107, 108 and 109, were synthesized by cold fusion of 9dCr and ^Fe ?08 209 projectiles with n?Pb and g3Bi targets. These heaviest nuclei are found to be surprisingly stable against spontaneous fission although their liquid-drop fission barriers are vanishingly small. Their stability is entirely due to shell effects. Hence, they may be considered as superheavy elements in a general sense.

- 3 - F. Sherwood Rowland Department of Chemistry, University of California Irvine, California 92717, U. S- A.

THERMAL AND ENERGETIC GAS PHASE REACTIONS OF RADIOACTIVE CHLORINE, FLUORINE AND HYDROGEN ATOMS WITH THE ORGANIC SUBSTRATES

High kinetic energy radioactive atoms arc produced by nuclear recoil from 37 38 19 18 neutron-induced reactions, including Cl(n,r) Cl, F(n,2n) F and He(n,p)T. These "hot™ atoms can react with various orgainc substrates by several general reaction mechanises, including T/H, Cl/Cl and F/F substitution reactions notobserved with thermal H, Cl or F atoms. The hot atoms can alternatively be thermalized by multiple collisions with inert or nearly inert molecules (e.g. CC1F-, SF_, CF., Kr), and 3 to 4 then provide excellent tracer species for study of chemical reaction mechanisms. The distribution of these radioactive atoms among various labeled products can be quantitatively determined by radio gas chromato­ graphy. The addition of halogen atoms to olefins is usually described as almost exclusively "anti-Markownikoff", indicating attachment of the to the less-substituted carbon atom, as in the reaction of Cl with CFl =CHBr to form the CH CICHBr radical. 2 2 However, CFF =CHX (X=F, Cl or Br) indicate that an important fraction of the initial reactions occur at the more-substituted carbon atom. The ratio of CH ClCHF/CH CHC1F is about 2 for temperatures from 232K to 350K, and addition to CH_=CHCl_or CH,=CHBr is even more equally distributed toward the CK and CHX ends of the molecules. The initially-formed radicals frequently isomerize, changing to radicals which appear to have followed the anti-Markownikoff addition rule, e.g. CFI CIIC1 -*CH C.1CHC1. Fluorine atom addition to the central position of propene to the CH-CHFCH radical which then decomposes to CH, plus CH =CJIF with a rate constant of about 10 sec . The similar addition of F to Sn(CH CH=CH > also creates a radical which decomposes to CH =CHF 8-1 with a rate constant of about 10 sec , despite 24 additional atoms and 72 more vibrational degrees of freedom. The most probable explanation for the lack of change in the decomposition rate constant is that the (allyl) SnCH CI1FCH radical is "non-RRKM", with the vibrational energy from the addition reaction unable to pass the Sn-C bond barrier.

- 4 - A CRITICAL REVIEW OF STUDIES OT THE EffEClS Or NUCLEAR CHANGES IN SOLID 5UB5TANCES

A.G. Haddock

University Chemical Laboratory, LensTield Road, Cambridge,

CB2 1EV4, U.K.

Studies of the chemical chanqos that ensue when the nucleus of an atom, combined in a molecule in a solid, participates in a nuclear reaction, such as radiative thermal neutron capture, isomeric transition or beta decay, have been pursued Tor more than f"i fty years. Although these efforts have had various rewards," such as the discovery of solid state exchange reactions, it is disappointing that in no system has a quantit­ ative understanding of what happens been achieved.

The reasons for such limited success will be explored and some suggestions marie regarding the most favourable direc­ tions for future work.

- 5 - Wang, De-X± Institute of Atomic Energy Beijing. China

SOME ASPECTS OF THE NUCLEAR FUEL CYCLE R S D WORK IN CHINA

The existing nuclear fuel cycle has been developed as a result of the defence program. In the establishment of such a NFC,, r and d work played an important role in the development of U-ore refining and conversion processes, gaseous diffusion process for O enrichment, fuel element fabrication technology, reprocessing process for the production of Tu and recycle of 0, as -well as processes for radwaste treatment and disposal. Beginning from the late 1970s, r and d efforts have been redirected towards the establishment of a NFC supporting the Chinese Nuclear Power Program based on LWR. Compared to the military program, this civil r and d program requires that the processes to be developed have to be more economical, more energy-saving, as well as more hazard- proof against undirected dispersion of radioactivity.

In the front end of the NFC, some of the existing advanced technologies such as high pressure leaching for u-ore refining etc. will be further studied and improved, and experiences in in-situ extraction of low-grade U-ore and recovery of U from unconventional sources will be further pursued. For U enrichment, new processes such as gas centrifuge and laser separation will be developed, and a chemical exchange system that can be more energy-saving than systems involving valence change of U will also be investigated.

In the fcac-Jc end of the NFC, much r and d work is being done to modify the existing Purex Process for spent LWR fuels. The head end is to be intensely modified so that 2r-clad LEU-oxide fuel can be treated. Also efforts are being focused on the development of-> partition and purification processes that would produce the least amount of liquid waste, that would be critically safe etc., and also on the development of equipments that would be more efficient and easy to operate and service. Work is being done on the separation of alpha-nuclides from HLLW for separate disposal and also on the recovery of noble metals contained therein. Various methods are available for the treatment of LLLW. Intense r and d work is going on for the vitrification of HI.LW, the bituminization of MLLW and also incoporation of radwastes in cement and plastics. A hydrofracture process is being developed for the final disposal of MLIiW at the site of a reprocessing plant. Furthermore, interim storage systems are also being considered.

- 6 - James D. Navratil RoclcweTl International, Rocky Flats Plant P. 0. Box 464, Golden, CO 80401 U.S.A.

RECENT ADVANCES IN AMERICIUM PROCESSING CHEMISTRY

Beta decay of Pu produces radioactively-pure Am. Separation and purification processes for Am include precipitation, ion exchange, and both liquid-liquid and molten-salt extraction. Recent advances in americium processing chemistry at Rocky Flats will be reviewed. Futhemiore, current studies on methods to remove americium from acidic waste streams using bifunctional organophosphorus extractants supported on solid membranes and spherical sorbents will be highlighted.

- 7 - GUnter Koch Institut fur Heisse Chemie, Kernforschungszentrum Karlsruhe Postfach 3640, D-7500 Karlsruhe, West Germany

THE PUREX SCHEME: RANGES OF CHEMICAL PARAMETERS

For more than 30 years, the PURFX process has successfully been applied to recover uranium and plutonium values from a variety of spent nuclear fuels, including uranium metal and alloy, uranium oxide, and mixed-oxide (HOX) fuel materials of widely varying irradiation and cooling levels. The process has thus proved to be highly versatile and flexible. The design of a PUREX flow scheme for specific fuel conditions requires the adjustment of various chemical parameters, as e.g. metal concentrations In feed and product streams, acidities of feed and reagent streams, type and concentration of reductants for U/Pu partitioning or Pu backwash, composition and metal loading of the organic solvent, etc. As a result, flow rates of process streams are derived for a given fuel throughput, which ultimately determine the size and design of process equipment. This paper is a review of published flowsheet data, and attempts to analyse the reasons of, and experience with, different sets of parameters applied in different PUREX plants.

- 8 - Monique PAGES Institut Curie - Section de Physique et Chimie Physico-chimie des Elements Transuraniens (U.A. CNRS 44B) 11, rue Pierre et Marie Curie 7!>231 PARIS C£dp.x 05 - France

Application of Mossbauer Spectroscopy to Actinide Chemistry

1L Is now t^cuqnL^eu" thai, the unusual electronic structure of the actinides (the 5f-electron shell) is responsible for their unique behaviour. The light actinidea in particular exhibit properties which are intermediate between those of the lanthanides (4f transition series) and those found in the 3d transition series. Mnssbauer spectroscopy is a currently used method of measu­ ring hyperTine interactions and is thus well suited to the study of properties related to the electronic configuration of ions hound in solids. This method has some distinct advan­ tages in the investigation of actinide compounds. In effect not only does the technique require relatively little sample material (10 to 10D mg is sufficient) but the material does not have to be single crystals since powder, amorphous sample or ev/en frozen solution may be used. Or particular interest in the case of the actinides is the Tact that the method is relatively insensitive to sample purity. By chance, one of the best Mbssbauer resonances available is Tound in I he actinide series ; it corresponds to the 60 keV transition in 237fjp. The other elements of the series have isotopes which permit Mossbauer spectroscopy but under fl^.-ch less favorable conditions. Moreover, neptunium with its numerous oxydation states (from III to VII), all of which are stable in the solid state, is an ideal representative of the originality of the light actinides. The neptunium resonance thus deserves to be a focal point of actinide Hossbauer research. Thus, in this review, we shall report mainly on some basic information related to the solid state chemistry oT the liqht actinides gathered using Np-M6ssbauer spectroscopy. firstly, the measurement nT isomer shifts permits an unam­ biguous determination of the charge state nf the actiniries in crystallized nr amorphous compounds. More generally, the Monshatier parameters can provide infor­ mation on An-1igand bonding, the symmetry nf the An site, the number and distribution oT the ligands surrounding the resonant atom, the presence oT cation complexes (Anfl2+ and AnO^"*"), magnetic transition and other difficult to acquire data.

- 9 - Zheng Qi-ke (Cheng Chi-ke) Department of Nuclear Science Fudan University, Shanghai, P. R.China

LASER APPLICATIONS IN CHEMISTRY OF URANIUM

Lasers have been developed to tlie point o£ being valuable tools in chemical research. This paper presents the application of lasers to the study of the chemistry of uranium at the Radiochemistry Laboratory of Fudan University.

(1) A tunable pulsed CO2 laser has been used to study infrared photosensitization of UFg by SFg. The vibrational energy transfer in SF6/UF6 system is investigated by observing the transient change in the UV absorption of the vibrationally excited UF, molecules. (2) A pulsed laser has been used to excited uranyl ions in acid medium. Luminescense decays and time resolved luminescence spectra of excited uranyl ions have been measured both in the aqueous solution and ."frozen solution". (3) Laser induced fluorescence has been successfully applied to the determination of ultratrace quantity of uranium. This method is applicable to environmental and biology samples and its detection limit is better than those of conventional methods. (4) A He-Cd continuos laser has been used to study photoreduction of uranyl ions in sulfuric acid and nitric acid solutions in the presence of ethyl alcohol. The quantum yields and the apparent rate constants are obtained.

- 10 - J. HOSTE Institute for Nuclear Sciences, Rijksuniversiteit Gent Proeftuinstraat 86, B-9000 Gent, Belgium

ACTIVATION ANALYSIS WITH CHARGED PARTICLES

ABSTRACT

Charged particle activation analysis (CPAA) has developed as a useful complement of the more usual neutron activation analysis. The latter does indeed not allow a practical and sensitive determination of light elements as hydrogen, boron, carbon, nitrogen and oxygen. Si­ milar problems are encountered with some medium and heavy elements as , cadmium, and lead, whereas a suitable choice of par­ ticle type, energy and nuclear reaction can solve these problems quite easily. Recent theories have also solved the standardization problems so that accurate results are obtained instead of the approximations used in the past. The widespread availability of compact variable energy cyclotrons has also contributed to the flexibility of CPAA, as a variety of par­ ticles e.g. protons, deuterons, helions-3 and -4 can easily be obtained in th* <»ni»J-gy r.»ng« o£ & f«jr MeV xrp to 20 MeV and even higher with suf­ ficiently high beam intensities to obtain excellent sensitivities often in the nanogram per gram range and reproducibilities within a few per­ cent. Special attention was also paid to proton activation analysis which allows selective determinations of a wide range of trace elements in different matrices. CPAA also made use of heavy particles in particular for the deter­ mination of traces of hydrogen and of tritons for the determination of Oxygen. CPAA was applied in wide range of matrices as for instance non fer­ rous metals and semi-conductors, rocks and soils, materials of biological Origin, environmental samples as aerosols, city waste incineration ash,etc CPAA also played an important role in the certification of reference rtjaterials issued by the Bureau of Reference Materials of the European 4ommunities.

- 11 - Tndashi N02AKI Institue of Physical and Chemical Research Wako-shi, Saaiaraa, 353 Japan

CYCLOTRON PRODUCTION (IP RADIOISOTOPES AND THEIR USE IN OTHER FIELDS THAN NUCLEAR MEDICINE

Recent progress of nuclear medicine is basal on the development of the following methods: (1) efficient cyclotron production of medical use Rl in high purity; (2] processing of the RI, especially rapid pre­ paration of radiopharmaceuticals labelled with short-lived no-carrier- added R5; and (3) nce.tsurement of in vivo distribution and its change with time for the RJ injected into a patient. Suitable production conditions (i.e., nuclear reaction, bombardment conditions and targetry) as well as the yield are known or can be predicted now for nearly all . neutron-deficient nuclides of tracer utility. Also, ultra-compact cyclo­ trons are available for in-house production of C-ll. N-13, 0-15 and F-18, together with apparatus for continuous supply of diagnostic use Rases and for automatic preparation of labelling precursors and some radiopharmaceutical compounds. Highly useful imaging devices especially for tomography have been developed, and the treatment of the data con­ cerning in vivo behaviour of RI has been systematized to be called tracer kinetics. It is quite clear that these methods of nuclear medicine can now be utilized in other fields of sciences and technology, especially in agricultural studies, where .only classical use of limited number of cyclotron RI has been undertaken. Longer-lived RI, such as Mn-54 (312 dj and Br-77 (57 h) rather than Mn-52 (5.6 d) and Br-75 (98 m), are often required or preferred, and economical production of long-lived Rl should further be studied. Various neutron-excess RI formed by the (0C,2p) reaction, such as Mg-28, Si-32 and Cu-67, are much interested in plant sciences, but are of low productivity. These IR are produced more efficiently by triton reactions, and tritoti bombardment facilities are Wanted. Generally in tracer study, the following directions seem to be promissing in near future development: (1) measurement of the time course for a physical and chemical migration by continuous injection of plural Rl of the same element but mrakedly different lives, which are often produced easily by cyclotron bombardment; and (2) simultaneous direct injection of various tracer into samples of various studies by bombardment with a high energy cyclotron. Some cyclotron Rl are used as sources for positron annihilation measurement, positronium study, Mossbauer spectroscopy, f-t angular correlation measurement, and EC X-ray spectroscopy. The latter three can give nondestntctively and continuously information-about chemical state of the Rl in the sample.

- 12 - I.A.lebedev, B. P.Myasoedov V. I.Vemadsky Institute of Geochemistry and Analytical Chemistry, USSR Academy of Sciences, Moscov, USSR

UNUSUAL OXIDATION aTAtfiS O? TttAN3i?U')TONiU!ft ELEMENTS AND THEIR USE IN ANALYTICAL CHEMISTRY AND TECHNOLOGY

Most of trans Plutonium elements (TPE) can exist in solutions not only in the "main" oxidation 9tate +3, but also in other oxidation states from +1 to +7. Use of these "unusual" oxidation states in analytical chemistry and technology makes it possible to sharply increase the effi­ ciency of separation procedures and the selectivitiea of analytical techniques. At present actually used in practice are Am(lV), Am(V), Am(Vl),-Bk(IV), fm;Il), Mn(l), Md(Il), No(ll); Cm(lV), Cm(Vl), Cf(lV), and Cf(V) have been proved to exist in aqueous solutions. In procedures of americium isolation and determina­ tion Am(lV) is widely used since recently together with Am(v) and Am(Vl). A number of highly selective coulometric methods have been developed for determination of microgram amounts of americium by the Am(lV)/Am(lIl) redox couple'. Solvent extraction of Am(lV) has been shown to be possible by amines from acid solutions containing ^n^o"^^!' Investigations on Ara(V) behaviour in various systems during extraction have shown this oxidation state to be perspec­ tive for selective isolation of americium. A large variety of methods for isolation and determination are based on Bk(IIl) oxidation to Bk(lV). Recently new methods have been worked out to oxidize berke- lium which supply complete oxidation without heating (oxi­ dation by KBrOv K?Cr«,07, a mixture of Ag and (NH.7pSp0R et til). Extraction of^Bk(IV) from acid solutions bj vari­ ous amines has been studied in detail. Bk(IV) has been established to be quantitatively extracted by amines from acid solutions containing %o 2 17^61* In heavy TPE separation metnods lower oxidation states are used. All the heavy TPE from to nobelium can be reduced to the divalent state, monovalent mendele- vium being possible to exist. Though Fm(ll) and Md(l) in aqueous solutions are not stable enough, in the presence of strong reducing agents (Eu2+, lb2*) they coprecipitate quantitatively with NaCl. The more stable are Md(II) and No(ll). Extraction and ion exchange procedures have been developed for their isolation.

- 13 - Chaise. Institute of Nigh Energy Physics, Acadonia Siiiic», P.O.Box 2732 Beijing, China

PRESEOT STATUS AND FUTURE PERSPECTIVE OF P1LE-NEUITOJ ,\TT1VATICN ANAhVSIS IN CHINA < a Review )

As a unique method in the arsenal of trace element analysis, NAA has 50 years1 history in the world and is blooming in Oiina, too, since the first experimental nuclear reactor was built in 1958. This paper will briefly simmrize sane important progress of its methodology and applies! ions in various fields made in tliinn and look forwnrd to Us future. The itans to be involved are as follows, nlong the working line of pile-neutron activation analysis. 1- Sampling 1) variation of elemental concentrations during sanple storage; 2) representative sampling; 3) preconcentrat ion and pretreat- nent of samples for special purpose. 2. Standard and SRM 1) a new mercury standard with sulfhydryl cotton matrix; 2) synthetic phenolic resin standard; 3) neutron activation R-mntrix elements and k -factor method; 4) preparation of geological, environmental and bio-logical SHVts for quality assurance. 3. Irradiation fncility 1) IVNR (miniature nuclenr reactor); 2) expe­ rimental heavy wnter-cooled reactor; 3) swinming-pool reactor. 4. Radiochemical separation I) procedure for separation of refractory sidcrophile elements based on thiourea chelate ion exchange resin; 2) a long chain primary amine for separation of noble metals; 3) ra­ diochemical noli vat ion determination of phosphorus; 4) application of di-octyl sulfide in platinum analysis; 5) radiochemical deter­ mination of mil tielemnnts in blood. 5. radiation detection and ganma speetrim analysis 1) 30 sets of Delhi) or HFV3i spectrometers with PDP lf/34, 23,

- 14 - G. STOECKLIN institut fnr Ch^mie 1 (Nuklearchemie) , Kernforschungsanlage Jtilich GmbH, D-5170 Juelich, Federal Republic of Germany

RADIOPHARMACEUTICAL CHEMISTRY OF RADIOHALOGEN COMPOUNDS

18 Tlie short-lived positron emitting radiohalogens F (T- ._ = 75 ' 110 min) and Br (T- .„ = 96 min) are finding increasing interest in Positron Emission Tomography (PET) while 123 I (T ._ = 13^2 h) is the most important isotope for Single Photon Emission Tomography (SpECT). The three radiohalogens can be produced in sufficient quantities at low and medium energy cyclotrons- The analogue approach allows the production of biochemically active radiopharmaceuticals for probing metabolism in-vivo using PET or SPECT.

Recent advances in the production and labeling chemistry of the three radiohalogens will be reviewed. Special emphasis will be given to the progress in the no-carrier-added chemistry of fluorine-18 and bromine-75, such as aminopoly- ethcr supported nucleophiiic fluorination and regiospecific bromodemetallation. The development of new synthetic routes for heart and brain agents such as fatty acids, amino acids, glucose analogues and halogenated butyrophenone receptor ligands will be outlined.

Of particular importance for the development of radiopharma­ ceuticals with radiohalogen substituents is the knowledge of the physiological acceptance, the metabolic pathway and in particular the fate of the label in-vivo. Examples of such studies -will be given for the above mentioned groups of radiopharmaceuticals.

- 15 - I,iu,l5-|.. Department of Chein. , Beijing Normal Univ., Bei jing, Cliina

IvAPTU 1.Sr.'r<>!'l': h'XCIIAFKik REACTION USE!) FOR RAD1 OilAI.OGEK LABELLING OF RAJHOPHATvMACEUTl OPI .S

'I'liu u^ed fur l"at>l,reliable and t^fficiuul r adiuliulo^eu isotope exchange proctnlurea for the B^ntlieses of radio­ pharmaceuticals has been rapidly increasing due to the availability of new compounds for imaging the brain, myocardium and orther organs using I'ET or Sl'RCT. In addition, due to availability of relatively short half life radionuclides. As a consequence, there is increa­ sing demand for rapid methods of prepari ng thorn. Tlie work described in this contribution deals with radio- halogen labelling of radiopharmaceuticals by three special exchange techniques which prove to he more effective than common thermal exchange procedures.These three techniques are: 1.1 ectopic exchange by Hydrothermal rnol t. method 2,Isotopic exchange in the pure crown ethers medium 3.1ootuE'ic exchange carried out in solid phaue The muln features of these techniques and their value with regard to practical applicability were described. A general chemical- kinetic equation describing inter- hulogen exchange reaction was also derived and discussed.

- 16 - Alfred P. Wolf Chemistry Departrapnt Brookhaven National Laboratory, Upton, NY 11973 VSX

FROSiEtiS J?; THE CHEMISTRT OF POSITRON EMITTERS AND APPLICATION TO PET STUDIES IN PATHOLOGICAL STATES

The positron emitters, carbon-11, nitrogen-13, oxygen-15 and fluorlne-18 are the most important tracers which can be prepared by small medical cyclotrons and which are in use today In the rapidly expanding PET (positron emission tomography) field- The exettatton functions and vtelds svalUMp from currently av.ill.iblo accelerators of the most frequently used nuclear reactions. C(p,cO C, 13 13 16 l3 14 l5 l3 15 I8 l8 C(p,n) N, 0(P,o.O N, N(d,n) 0, N(p,n) 0, 0(p,n) F and 2oNe(d,a)1?H" will he considered in light of the biomedical research and clinical applications to which these radionuclides are to be put. The preparation of precursors, especially those containing carbon-ll and fluorine-18, used in the synthetic procedures, by in- target hot atom techniques and rapid automated synthetic techniquesat EOB (end of bombardment) will be discussed in the same context. The tracer method, first elucidated by Gyorgy von Hevesy, is the fcey -element in the use of PET. The positron labeled organic com­ pounds are the biochemical probes which allow us to study a wide variety of normal and pathological Btates in human beings in a manner not heretofore possible. The two probes which led to the rapid evolution of evaluating human jLn vivo biochemistry and physiology were oxygen-15 In labeled O2, CO, CO2 and H2O flnd 18F -fluorodeoxy- glucose- These metabolic probes came into prominence in the middle 70's. A wide variety of other tracers have become available since that time (J.S. Fowler and A.P. Wolf, Nuc. Scl. Series, Natl. Acad. Sci-, Monograph, 1982). Notable new successes have been accomplished with neuroreceptor llgand compounds for studying mental illnejs particularly schizophrenia, and other disorders such as Parkinsonism, polyamlnes for tumor evaluation, fatty acids for metabolism In the b^.-jrt, ast-o acids for protein synthesis and metabolism, enzyme inhibitors for evaluating dynamic aspects of enzyme function, and other in vivo biochemical processes. Special emphasis will be given to neuroreceptor llgands such as the labeled hutyrophenones and dopamine, tumor specific compounds such as ^C-labeled putrescine, and enzyme inhibitors such as L-deprenyl for use In studying disorders due to MAO excess or deficiency. PET is a unique tool in that given appropriate biochemical models and labeled tracers, human biochemistry can be quantitatively mea­ sured and evaluated. In thi9 regard it is different from CT (computed tomography) and NMR (nuclear magnetic resonance) whose major strengths are as imaging modalities and SPECT (single photon emission computed tomography) which is a qualitative technique similar in some respects to PET. These various modalities are not mutually exclusive, they are complementary and accomplish different objectives all of which are important to understanding normal and digeased states in human beings. The presentation will attempt to delineate the unique aspects of PET and its stimulus for explaining new avenues of radiochemlstry and radiolabeled tracer preparation. Research supported by US DOR and OHF.R. - 17 - M. Sakanoue. Low Level Radioactivity Laboratory, Kacazaua University, Tatsunokuchi-machi, Ishlkawa, 923-12 JAPAN.

TRANSURANIUM NUCLIDES IN THE ENVIRONMENT.

Japanese people were, firstly in the world, subjected to the transuranium fallout due to the atomic bomb explosion at Nagasaki, as Prof. G. T. Seaborg wrote in his book "The transuranium elements'* that the announcement to the world of the existence of plutonium was in the form of nuclear bomb dropped over Nagasaki in 1945. On the other hand, according to the recent development of nulear Industry, all people In the world are now confronting with the problems relating to the safety disposal of nuclear waste containing rather high level transuranium nuclides. From these standpoints of view, the studies on the distribution and the behavior of transuranium in the environment become very important and are now actively made In the world. A review of these studies, especially made in Japan, will be reported in this lecture. The high accumulation of Pu-239 in the surface soil of Nagasaki was found about 17 years ago by us at Nishiyama area where the black rain came down just after the atomic bomb explosion. Since these studies, by introducing newly developed radiochemical methods and Instruments,environmental plutonium isotopes (Pu-239,240, 238), americium-241 and recently Np-237 in various samples have been studies for their distributions, depth profile, variation with time and the relationship with organic materials in several samples. The Interesting informations have been obtained for the following samnles. The samples relating to "Bikini event" of 1954, the surface soil and sea/lake sediments samples collected at vavlous locations in Japan, the sea water samples collected from Japan sea and the Pacific Ocean, and the atomospheric aerosol over Japan and so on. DiBcusslons will be made for these results.

- 18 - Robert J. Silva Lawrence LIvennore National Laboratory Livermore, California, USA

THE CHEMICAL BEHAVIOR OF ACTINIDES IN ENVIRONMENTAL WATERS

The chemical behavior of the actinides U, Np, Pu and" An are being investigated in connection with plans for underground storage of* high-level nuclear waste. If released to environmental waters, the concentrations of these elements may depend on the nature and solubilities of compounds that form with inorganic anions in the waters. The solubilities will be modified by the formation of solution complexes with Inorganic and organic ligands in the waters. The current status of measured and estimated thermodynamic constants for the formation of appropriate compounds and solution complexes will be discussed and summarized. Solubilities and speciation of U, Np, Pu and Am in some typical environmental waters, calculated with the geochemical modeling computer code EQ3/6,will be presented and compared with recent experimental measurements. This work was supported by the Nevada Nuclear Waste Storage Investigation of the Department of Energy.

- 19 - Discussion Papers

1. Nuclear Reaction Chemistry

i

- 20 - J .P. AQloff, K. Rbssler Laboratoire de Chimie Nueleaire, Centre de Recherches r&icleaires ^67037 Strasbourg, France Institut Uir Cnamie 1 (Mjklearcheinie) Kexnforschuqgsaru age Julich 5170 JUlich, RFA

CHEMICAL EFFECTS OF a DECAY IN URANIUM MINERALS

234 238 The disequilibrium of U and U in nature has been 234 attributed to the physical ckanage induced ty the 'Vh alpha recoil 234 (1) atom and the ensuing preferential leaching of U The effects of a decay in uranium compounds have been revisited on the basis of (2 3) experimental data on hot atom chemistry of uranium " and of compu­ ter calculations of the collision dynamics of uranium atoms in model f 4} 234 238 substances . A "chemical" mechanism for the LI/ U disequili­ brium has been worked out. The role of oxidation processes due to (5) oxygen defects induced by recoil atoms is emphasized Tlie calculations reveal that in dense uranium compounds such as UOp, most of the uranium recoil atoms end in a tetravalent state and are not leachable. Reciprocally, in media with low uranium compourfds a high proportion of the recoils is stabilized in the solu- ble hexavalent state. Measurements of the U/ U activity ratio in various uranium minerals confirm this mechanism. Little or none disequilibrium is found in uranium rich minerals (= bO %) whereas 23~? uranium poor minerals (< 1 %) are markedly depleted in ' U. The new mechanism has obvious implications in geochemis­ try of uranium and holds for any heavy projectile in oxygen contai­ ning matrix. Thus it should be applicable to the leaching of at decay products out of radwastes.

(1) R.L. Fleischer, O.E. Raabe, Geochim. Cosmochim. Acta 42 (1978) 973/8 (2) J.P. Adloff, Radiochimica Acta 29 (1981) 5 (3) K. Rbssler, in Uranium Suppl.A6, Gmelin Handbook of Inorganic Chemistry, Springer, Berlin 1983, 135/64 (4) K. Rbssler, Intern.Conf. on Nuclear Chemistry, Lindau, FRG, (1984), paper 5.36 (5) K. Rbssler, J.P. Adloff, Proc.Intern.Meeting Concentration mecha­ nisms of uranium in geological environments, Nancy (1985) 295/297.

- 21 Han H.Y., Huang S.M., Meng J.C., Bao Z.Y. and Ye 2.Y. Institute of Atonic Energy, Beijing* China

THE KINETIC ENERGY CORRELATION AND THE BEHAVOUR OF NEU­ TRON AND Y-RA.Y EMISSION IN TERNARY FISSION OF Cf-252

The kinetic energy correlation and the characteristics of neutron and "jf-ray emission in triton and LRA accom­ panied fission of Cf-252 were investigated in three se­ parate experiments. The kinetic energies and mass ratio of a pair of main fragments were determined by two sur­ face-barrier type Si detectors. The light charged par­ ticles were identified by using a AE-E telescope which is consisted of Si detectors. The prompt fission neu­ trons were detected by means of a Gd-loaded liquid scin­ tillation tank. The prompt fission "f-photons were mea­ sured with a Nal(Tl) scintillation counter. The results show that the mean total kinetic energy (TKE) of two main fragments in triton accompanied fission is 1.7 MeV higher than the TKE in LRA accompanied fission,but 10.7 MeV lower than that in binary fission. TKE as a function of the fragment mass ratio in above mentioned three fis­ sion modes are three curves with similar shape but dif­ ferent absolute values. The average numbers of prompt neutrons per fission for LRA,He-3, triton and proton ac­ companied fission are equal to; 3.13±0.02, 3.09±0.09, 2.95±0.O5 and 3 . 24±0 .07,respectively. For LKA and triton accompanied events, the average numbers of prompt ^-pho­ tons emitted per fission are the same within the statis­ tical accuracy (1.5%), but in both cases are 15£ lower than that in binary fission. Other detailed correlation characteristics are also presented and discussed.

- 22 - V.B. Viola and T.B. Walker, Indiana University, and G.J. Mathews, Lawrence Llvermore Laboratory

NUCLEOSYNTHESIS OF THE LIGHTEST ELEMENTS

While the elements carbon through uranium are synthesized primarily during stellar evolution, the light elements H, He, Li, Be and B find their origin In less-dense, more energetic astrophyslcal settings.* Cosmologlcal nucleosynthesis in the big bang can account for lH, 2H, 3He, 4He and perhaps 7Li rather well. With the possible exception of 7Li, the production of Ll, Be and B (LIBeB) is strongly Inhibited In the high-temperature environments associated with both stellar evolution and the big bang due to the loosely-bound nature of these nuclei* For this reason low-density mechanisms which involve energetic collisions of protons or alpha particles with He and heavier nuclei (primarily HeCNO, the most abundant species) are usually postulated as the source of most LiBeB. The objective of the present analysis is to re-examine models of LiBeB nucleosynthesis in light of the rather complete excitation functions which now exist for the salient nuclear reactions. Three models are investigated—nucleosynthesis induced by galactic cosmic rays (GCR) in the interstellar medium (ISM), flare spectra, and shock waves. Only the GCR + ISM calculation Is able to provide a reasonable account of the experimental abundances. The flare spectra demand ^Li/Be and B/Be ratios far in excess of experimental abundance ratios while the shock wave calculations are only reasonable for a very narrow range of monoenergetic (E/A) spectrum near 10 MeV/nucleon. The present results for the GCR + ISM calculation are able to l account for the absolute abundances of *>L1, °Be, 10B and * B satisfactorily. On the other hand, the more-sens itive 7Li/6Li and llg/lOg isotope ratios are found to be well outside the experimental limits of error. The HB/1°B ratio can be explained by the existence of a low-energy component of the GCR transported flux of the form *(E) a E~T where T • 5-7. The inability of the GCR + ISM mechanism to account for the 7Li/6Li ratio has long been recognized.1 Since 'Li is also produced in big bang nucleosynthesis, the 7Li/°Li isotopic ratio can be most easily understood in terms of a model In which the major source of 7H is the big bang and that for ^Ll is the GCR + ISM mechanism. In fact, using the standard model and a universal baryon density which reproduces the observed ^H, ^He and ^He abundances, cosmological nucleosynthesis calculations produce the correct amount of 'Li required to yield the observed 7Li/6Li ratio.

1) Sam M. Austin, Prog. Nucl. Phys. 7, 1(1981). - 23 - P.P. Hurte, S.P. Dnnqr, S.K. Das, T. Datt-.-i, S.ri. iic.^|,r,,.,l;h, A. Gosuismi, S.B. flanohar, H. fJeik, A.G.C. Nnir, A.V.ft. Heddy, S.n. Sahakundii, B .S. Tomai, B.K. Sriwai?tava, Satya Prnknsh and I.V. Ils»maniah

Tadi ochcrmistry Division, Bhablia Atomic nr>",pardi Ontro, Trnnb.i)' , Bombay—& 00 085, INDIA RAOIOnilElHICAL STUDIES 01! F1SSIHN

In order to iwns t ig atn the rolrs of frnqmnul; nircjenr structure, excitation energy and or rissioning nuclei on the V»r«c*j:;s oT fission, radiochemical studies UPHC^ cm r led out on isotcipic yislcl9 and fragment angular momenta. Tho Isotopic yield distribution for technetium and independent isomeric yield ratios for Te-131, Te-133 and 1-132 were determined in the low energy fission of Pu-2

Pu-24l(nth.f)» Np-237(n,f), Am-2

The measured independent isomeric yield ratios were used to deduce fragment angular momenta Tor Te-131, Te—133 end 1-132 using statistical model baaed analysis. It was seen that the odd rragmenta have higher angular momentum and hencB higher deformation compared to the neighbouring even fragments possibly due to polarization oT the even -Z core by the odd proton. Influence of the deformed P6n and spherical B2n shells on the scission configuration was evaluated in terms of the fragment deformation at the scission. Fission process involves readjustment of nucleons between the two separating fragments which is manifested in (1) the difference between the most probable mnes/charge of fragment to that of the fissioning nucleus (oTten referred as mass/ charge polarization) and (2) width of the mass/charge disper­ sion. In order to investigate the dependence of mass/charge polarization on the nature of fissioning nucleus and excitation energy Isotopic yields of iodine in the fissioning systems mentioned shove were determined gamma spectrometricaily following radiochemical separation of fission product iodine. The most probable mans (Ap) and width of the distribution ( CTjf), for all fissioning systems were obtained using isotopic yielri9. These 3tudlB3 showed that (J/j increases with the fis9ility pararneter and alsowith excitation energy which was explained in terms oT the nature of descent bf the fissioning system p«st the second saddle. _ 24 _ K. Aleklettd), R. Brandt(2), H. Bronikowski(3), V.S. But*ev(4), G. Dersch(2), G. Feige(2), E.M. Friedlander(5), E. Ganssauge(6), G. Maase(2), J. Herrmann(3), D.C. Hoffman(5), B. Judek(7), D. Lee(5), E.J. Langrock(8), P. Hc6aughey(5h P- KozmaH), B.A. Kulakov{4), W. Loveland(9), F. P111e(8), N.T. Porile(3), W. Schulz(4), G.T. Seaborg(5)

UNUSUAL PROJECTILE FRAGMENTS FORMED IN RELATIVISTIC HEAVY ION INTERACTIONS STUDIED WITH NUCLEAR CHEMISTRY TECHNIQUES

Projectile fragments foraed in U«» Interaction of relativistic heavy ions within a 1 cm thick Cu disk interact with a second Cu disk placed downstream. The relative yields of radioactive products in the two disks are measured by radioactivation techniques off-line using conventional Ge(L1)-detectors. Of particular interest are deep spallation products 22 24 ''S like Na, Na and "" Hg, which are formed predominantly by high-energy particles (E > 1 GeV). The cross section ratio RQ of "downstream/upstream1' Cu disks being in close contact (d=0 cm) was Studied for

24 GeV protons (PS. CERN), 25.1 GeV 12C (BEVALAC, LBL) 36 GeV 40Ar (BEYALAC, LBL), 48 GeV 4He (PS, CERN) 54 GeV 12C (Synchrophasotron, JINR), and 72 GeV 40Ar (BEVALAC, LBL).

The ratio RQ (d=0 cm) scales with the total energy of the projectile; juch an increase is hard to interpret - at present - with conventional model s. Furthermore, the variation of R with increasing distance d between the two Cu disks was studied for some of the above-mentioned systems. for total energies below E £40 GeV no unusual behavior of R with d 40 could be found. The experimental results for 72 GeV Ar demand either fl) decay in flight (t.,. — 10 s) of some projectile fragments having Jarge cross sections or (2) production of secondaries with unexpectedly large transverse momenta (see G. Dersch et al., Phys. Rev. Lett. 55_, 1176-1180 (1985).

1) Studsvik, Sweden, (2) Kernchemie, Marburg, F.R.G., (3) Chemistry, Purdue, Ind., USA, (4) JINR, Dubna, USSR, (5) LBL, Berkeley, Cal., USA, 16) Physik, Marburg, F.R.G., (7) NRC, Ottawa, Canada, (8) TH Leipzig, Leipzig, German Dem. Rep., (9) Chemistry* Oregon State, USA - 25 - Z. Chen, C.B. Chltwood, D.J. Fields, C.K. Gelbke, « W.G. Lynch, J. Pochodzalla , and M.B. Tsang

National Superconducting Cyclotron Laboratory, Michigan State University,East Lansing, MI H882H. USA

DEPENDENCE OF SOURCE RADII AND EMISSION TEMPERATURES

ON LINEAR MOMENTUM TRANSFER1"

Two->particle correlations at small relative momenta were measured tor l*N induced reactions oi\ ,,?Au at E/A - 35 MeV. The measurements were perfrcmed at mean laboratory angles 6 - 20°, 35° and 50°. The apace-time extent of the emitting system was investigated by the technique of nuclear lnterferometry Cl]- In order to explore the dependence- of the space-time extent of the system on the energy of the outgoing particles, two-particle correlation functions were evaluated with different constraints placed on the summed kinetic energy of the two coincident particles. More pronounced correlations were observed for larger kinetic energies, indicating that more energetic particles may originate from subsets of nucleons which are more localized In space-time. Additionally, emission temperatures for 'Li and 'Li of about 5 MeV were deduced from the relative population of excited states. For 'Li nuclei, emission temperatures were extracted which increased with the total kinetic energies of the emitted particles [2].

In order to study the dependence of the source parameters on the linear momentum of heavy residual nuclei produced in fusion-like reactions, four-fold coincidences between two light particles and two fission fragments were seasured. The linear aosenttc was deteroined C3] from the folding angle, 9,,, between the two fission fragments. As an example, we made the correlation functions for coincident deuterons and alpha- parti cles for three different constraints on Qlt . The d-a correlations are more pronounced with increasing mom en tun transfer.

References: *) Fellow of the Deutsche Forschungsgemelnschaf t (DFG, Germany) t) Work supported by the National Science Foundation under grant PHY. 83-12215

[1] D.H. Boal and J.C. Shillcock, Phya. Rev. C33 (1986) 5H9 [2] C.B. Chltwood, C.K. Gelbke, J. Pochodzalla, Z. Chen, D.J. Fields, W.G. Lynch, R. Morse, and M.B. Tsang, Phys. Lett. (In press) [3] T. Sikkeland, E. L. Haines, andV.E. Viola, Phys. Rev. \25 (1962) 1350 - 26 - David J. Morrissey

National Superconducting Cyclotron Lab Michigan State University East Lansing. Michigan, USA. i48824

NUCLEAR TEMPERATURE AND EXCITATION

We have developed a new technique for measuring the nuclear temperature of fragments emitted during a broad rdi!(j« of reactions. Examples of the relationship between the temperature and the internal excitation energy of a system famllar to chemists are the distribution of the population of a-molecular system among its vibrational, rotational acid electronic excited states and the Maxwell-Boltzmann distribution of velocities of gas particles. Similarly, it is well known to nuclear scientists that excited nuclei radiate particles (neutrons, protons and light nuclei) with Maxwell-Boltzmann velocity distributions which has been used to estimate the temperature of the nuclear source. We have recently suggested that the thermal equilibrium Implied by the existence of a nuclear temperature should also produce a characteristic distribution of the population excited states of complex nuclei emitted by that source Cl,2]. The data showed that the actual population of excited states is dramatically lower than that which would be consistent with the kinetic energy distributions of the same particles In a particular intermediate energy reaction, 490 MeV i"N +• Ag. However, in the low-energy compound nuclear reaction of ''•N + ,2C the excited states of the radiated nuclei have been shown to be in equilibrium for bombarding energies in the range of 87.5 to 112 MeV. This latter reaction is, in essence, a calibration of the technique which we have recently completed. The initial work concentrated on measuring the populations of lithium and nuclei which" have only one bound excited state. Recent measurements included analysis of the deexcitation Y-raya from ,0B which has several bound excited states. This research has been carried out at the National Superconducting Cyclotron Laboratory at Michigan State University and supported by the NSF under Grant 83*12215.

1. D.J. Morrissey, et al., Physics Letters 1 U8B (198*0 ^23 2. D.J. Morrissey, et al.. Physical Review C32 (1985) 877

- 27 - William B. Walters Department of Chemistry University of Maryland College Park, Maryland 20742 USA

THE STRUCTURE OF 000-000 TRANSITIONAL AND NEAR-CLOSED-SHELL NUCLIDES.

Recent investigations of the structure of odd-odd nuclei irt both transitional nuclides and nuclides near closed shells have demonstrated the value of these data in characterizing the residual interactions between unpaired protons and neutrons. In recent studies of the structure of 132Sb populated in the decay of double-magic "*Sn members of all of the positive parity multiplets expected below 2 MeV have been Identified. These results can be compared with the results of calculations using realistic shell model potentials that yield considerable insight into the Interaction between the single 51st proton and the single hold In the N = 82 closed shell. Considerable increased complexity 1s observed for the levels of 130Sb populated 1n the decay of both the 0+ and 7" Isomers because of the two additional neutron holes. Structures of the odd-odd La nuclides populated in the decay of even-even neutron rich Ba nuclides show a very different pattern. The most easily followed systematic feature Is the position of and 6 feeding to the lowest lying 1+ levels. Only a small number of 1+ levels are strongly populated in the N = 84 and 86 nuclides, but with the onset of deformation in H = 88, strong 6 decay Is observed to over 20 levels.

- 28 -- 0. Kopecky, K. Abrahams and F.- Stecher-Rasmussen Energy Research Centre Netherlands (ECN), Petten P. Poiak and 1. Lindner National Institute of Nuclear Physics and High-Energy Physics (NlKHEF, section K), Amsterdam ISOMERIC NEUTRON CAPTURE CROSS SECTION OF 175Lu AT STELLAR TEMPERATURES

A new facility at the High Flux Reactor (HFR) in Petten, provides a 24.3 keV neutron heamfFMMM = ?. keV), by nassing reactor neutrons through a special iron filter. The beam which has a flux density of 6.6 x 10» n.cmr^s-i covering an area of 5 x 5 cm2, is one of the best of such facilities 1n the world. The energy of about 24 keV well approximates the thermal equili­ brium with stellar surroundings for the s-process of nucleo­ synthesis. The importance for astrophysics of good knowledge of neutron capture cross sections at stellar temperatures has recently been discussed *). Of special interest is the neutron capture to the 3.63 h isomeric state in ^^Lu 2,3)> the cross section of which is needed with high precision. The above beam specifications, more particularly in combination with a more sensitive detection technique - 4it beta liquid scintillation counting - seemed ideally suited to provide a new and promising approach. The actual mea­ surements have yielded a value of 0.87 + 0.03 barn for the isomeric neutron capture cross section Tn 175LU at 24 keV. Gold was used as a standard with o = 0.621 + 0.003 b 4). Our value seems to settle a major discrepancy of about 30 % between two reports 1n the literature 2,3), in favour of the result obtained by the Karlsruhe group 2). The implications of the measurements will be briefly discussed. References 1) G.J. Matthews, R.A. War.d, Rep. Prog. Phys. 48 (1985) 1371 ?.) H. Beer, F. Kanpeler, Phys. Rev. C21 (1980) 534 3) B.J. Allen et al., J. Phys. G7 (1981)'127P 4) R.L. Macklin et al.. Phys. Rev. Cll (1975) 1270

- 29 - K.Sakamoto, Y.Hamajima, D.Sato.Y.Kubota, N.Yoshida T.Has&iniotq^T. Fukuzawa ,S. Shibata* and I .Fujiwara**

Department of Chemistry of Kanazawa University, Kanazawa 92QJapan. ^Institute for Nuclear Study,Unversity of Tokyo. Tanashi Tokyo 188 Japan. ** Instsitute of Atomic Energy,Kyoto University, Gokasho Uji 611 Japan.

PHOTOSPALLATION REACTIONS IN 51V, 89Y,127I AND 133CS

Yie Ids of ph otosu allation re actions in5l-ir,89-ir,l '17-1 andl33- Cs have b een m easured wit h activatin method in the energy range bet ween 100 MeV and 1 GeV. Targets of me tallic vanadiu m, metall ic yt trium, pota ssium iodide and cesi urn chlorid e were ir radia ted «ith th e breassstrahlung from »1 ectro n LINAC o f LNS of Tohoku unversity and elctron syncrot ron of IN S of Tokyo unive rsity The -f-activiti es of spal latio*n pr oduct s were meas ured with Gelli) dete ctors nondest rac ti vely and/ or after ch emical separations.Th e yi elds of the re actio ns are obta ined on the activatio n formula after th e cor rection fro m genetic relationshi P- For a e xample.th e yie Id curves o f 89-V{y,xn yp) react ions are sho wn in Gig .1. S ome of the yield values were com pared with pr evi oudata (1) a nd the agre ement amnog them are good. The exp erimental yiel ds were ana lysed with Rudstam's em pi ric al formul a(2) and obtaine d parameters are disc ussed systema tically. Param eter P deer eases with the increa se of bremsst rahlung e nergy below 600 MeV and levels off as shown i n FiG.2, thi b ehaviour is similar wi th the 1 imitti g behaviu or in the high "energy int e-raction of charged particl es.Howeve r, br emstrahlung has continuous spect rum, ft is v ery inter est t o know how change will be shown in this $fr enomena a fter unfolding t he spectum. ihe unfol ding for the purpose in pr ogress.

i«

-O-O- •ft.

«-o- •-•-•Ito--rM* y 0.1 - 0 1 J i »""» i~f 1 > o at 1 10(GcV) ' =» Kn.iniplet ul ylfkl curves (or Maximum bremsstrahlung energy H V(r,xnjrp) reaction ai » function f ' 9 • 2 iMimelcr r" as • function ol £,. The circlet drmile '"C» of E% Tlie KOIM curves are drawn (or • nd the triangle, denote "*l : open •ymbult-tltli work : closed eye-guide symbols-id. 9 (i^i SOOKfcV ) and leC References l)K.Lingern and G.G.Jonsson Nucl .Phy s. A 197(1971) 71 21 a (1966) 1027. 2)G.Rudstam. Z.Naturforsch, - 30 - James J. Hogan. David J. Parker and James Ashei Department of Chemistx-y, HcGill Univexsity Montreal, Quebec, CANADA Nuclear Physics Division, A.E.R.E Harwell vQ*:i&Guu2siiiires» JJ.K-

INCOMPLETE FUSION IN LIGHT HEAVY-ION INDUCED REACTIONS.

A method has been developed using a variety of experimental ap­ proaches to isolate and characterize trie muit\yAc i\icotc»piete tvision processes competing in light heavy-ion induced reactions at energies from 6 to 10 MeV/nucleon. By this approach, a given reaction leading to a specific product may be understood to occur by one of several mechanisms, with the contribution of each component evaluated. The experimental techniques employed include the measurement of the diff­ erential and integral recoil properties of a variety of products, and their excitation fun< ^ions, as well as the double differential part­ icle spectra with particle identification. The overall effect is of a double crystal ball experiment in which the properties of the pro­ duct nucleus as well as those of the resultant fragments are measured, the added information obtained being average properties rather than event-by-event correlation. Several reaction systems have been studied including five inci­ dent projectiles (12C - 20Ne) on 51V, and 20«22Ne on 93Nb. In the former case, twelve radioactive products have been studied by gamma- ray spectroscopy; in the latter, about thirty reaction products were isolated. Particle spectra have been measured for all fragments at angles from 10° to 150° with respect to the beam axis. The model forming the analytical basis may be summarized as fol­ lows: An incident heavy ion may undergo complete fusion with a tar­ get nucleus, or may undergo two-body breakup,- one fragment fusing, t)*e ot*her continuing in flight vith its trajectory RnoxJified by the interaction. The resultant excited intermediate nucleus, possessing high angular momentum, recoils with an angle, excitation energy and kinetic energy obtainable from the kinematics of two body breakup. This excited nucleus then undergoes evaporation of neutrons and a particles consistent with its excitation energy and angular momentum until a final reaction product is formed. This product is character­ ized by its yield, consistent with that of its complimentary fragment and a recoil range and angle consistent with the two-body breakup kinematics. All of these-quantities have been measured. The differential recoil distributions for a given product typi­ cally show distinct peaks attributable to one or more incomplete fu­ sion processes and, in some cases, complete fusion. Coupled with measurement of the average angle of recoil in integral range experi­ ments, these provide the kinematic parameters of the recoiling pro­ duct nuclides. In turn, these have been correlated with the double differential particle spectra to provide a complete picture of the reaction mechanism,(s) leading to formation of a given product.

- 31 - Sun.T.Y. .Li.^.X.,Dong.T.R..Jin.G.M. ,Fu,M. ,Sun,X.H., and Sun,X.J. Institute of Modern Physics Lanzhou, China RECOIL STUDY OF RESIDUAL NUCLEI IN THE REACTION INDUCED BY 12C QN 115In

Excitation function and angular distributions of the heavy residual nuclei, I(Z=53) and Sb(Z=51), have been measured in the reaction of incident C on In(Z=49) at energies up to 72 MeV using radiochemical techniques. A kinematic analysis of the angular distributions has shown that the peak at about 13* (in Lab system) for I isotopes can be attributed to a evaporation by compound nucleus and an incomplete fusion with a strongly-damped sticking rotation,followed by the evaporation of neu­ trons. At the incident energy of 69 MeV, the breakup- fusion process with incomplete momentum transfer begins to occur, leading to the production of I isotopes peaked at approximately 25". The total cross-section of produ­ cing I isotopes hy last two non-compound-nucleus reac­ tions (also called "^Be transfer") is of the order of 100 mb and is much larger than that for a transfer which is estimated to be about 17 mb by summing the cross-sections of Sb isotopes. The experimental results are in good agreement with the measurements of the out- going a particles in the similar reactions. (1)'

Reference: (1) Dai Guangxi et al., " Heavy Ion Fusion Reaction " Proceeding of the Tsukuta International Symposium (1984) P.'218'.

- 32 - I. Fujiwara, S. Shibata? M. Imaniura* M. Soto, Y. Kubota+ M. Yoshidaj Y. Hainajima^ and K. Sakamoto* Institute

ISOTOPE YIELDS IN (y.-iTxn) REACTIONS IN COMPLEX NUCLEI

Radiochemical yields of photonucltar reactions, such as 133m,8xe from 133Cs(Y,Tt+) reaction, Ba isotopes from 133Cs(Y,-n~xnJ133_xBa for x = 0,2,4,5 and 7, Xe isotopes froa 127I (Y,w"xn)127-xXe for x = 0,2,4,5 and 6, Zr isotopes from 89Y(Y,n"xn)89~x2r for x= 0,1,2 and 3, 62Zn from 63Cu[Y,n"~n) and 65Cu(Y,7t~3n) reactions and Cr isotopes from 51V(Y,7i~xn)5l~xCr for x = 0,2 and 3, were measured for brentsstrahlung end-point energies (E0) of 100 to 1000 MeV. An emphasis in the meas­ urements was placed on runs around the pion threshold and also on runs for different target thickness to assess the contribution of the interferring secondary particle-induced reactions. It was found that the yields show steep rises around or several to a few tens MeV lower than the Q values, in consistent maimer with increase of the reaction thresholds. At E0 above about 400 MeV the yields increased scarcely. The yield curves as a function of the r.umber of emitted neutrons are of bell-shapes for heavier targets and for Eu above 400 MeV, and vary regularily with target masses and

EQ. The secondary particle-induced reactions were found to be unimportant in the experiments for different targets in thickness It is suggested from the target mass dependence of the reaction yields that measured photonuclear reactions are interpreted neither by surface- reaction model nor volume-reaction model, except for (Y,TT~) reaction.

- 33 - K- Aleklett.a W. Lovelandb and G.T- Seaborgc

The Sfcudsvik Science Research Laboratory, S-611 82 Nykoping, Sweden Oregon State University,Corval1 is, OR 97331, USA Lawrence Berkeley Laboratory, University of California, USA

HEAVY FRAGMENT PRODUCTION IN INTERMEDIATE ENERGY HEAVY ION REACTIONS*

We report the results of measurements of the yields, energy spectra and angular distributions of the heavy (Ac-.-50

*} Work done by the Berkeley - Corvallis - E. Lansing Goteborg - Orsay - Studsvik Collaboration. - 34 - 6. Skarnemark , M. Skfilberg , N. Kaffrell , J. Rogowski , H. Tetzlaff , N. Trautmann , J. Alstad

SISAK - A TECHNIQUE FOR STUDIES OF FXOTIC NUCLIDES

The SISAK technique (Short-lived Isotopes Studied by the AKufve technique) enables on-line studies of short-lived nuclides separa­ ted chemically from complex reaction product mixtures. The techni­ que applies multistage solvent extraction steps, where rapid phase separation is achieved by using specially designed centrifuges with short hold-up times. The radionuclides are transferred from the production site to the S7SAK equipment with a gas-jet transport system. Recently, the SISAK facility was upgraded to give access to nuclei with half-lives down to about 1 s.

So far, chemical separation procedures with overall hold-up times between 2 and 7 s have been developed for Cu, As, Br, Zr, Nb, Tc, Ru, Pd, I, la, Ce, Pr, Th, U and Np. By Y-ray singles spectra, half-life-, YY-coincidence- and YYangular correlation measurements detaile.,..,d. spectroscopi. .c .investigation 4.4.- s of* 68-70Cur , 86-89BrD , 100Zr, , 100... 106-108 . 107-112 113-116 . 143-148. 145-150- Nb, T/Tc, RuDi , PdD , La, Ce, Pr and ~ Np have been performed. Studies on the chemi­ cal behavior and on the decay properties of the heaviest elements are also planned with the SISAK technique. For this the equipment will be scaled down, and techniques for on-line measurements of a- and p-radiation will be developed.

Furthermore, partition coefficients and complex formation constants can be determined with the SISAK system, and the kinetics of solvent extraction processes and redox reactions can be investigated.

_ Department of Nuclear Chemistry, Chalmers University of Techno­ logy, S-412 96 Gbteborg, Sweden ** Institut flir Kernchemie, Universitat Mainz, D-6500 Mainz, Germany *** Department of Nuclear Chemistry, University of Oslo, N-0315 Oslo, Norway - 35 - A. Tiirler, H-R. von Gunten? Laboratorium fiir Radiochemie Universitat Bern, 3000 Bern 9, Switzerland. D.C. Hoffman, K. Gregorich, D. Lee, M.J. Nurmia, R. Hen-- derson, H. Hall, B. Chasteler, G.T. Seaborg, Lawrence Berkeley Laboratory, Berkeley, CA 94 720, USA. BELOW-TARGE'f YIELDS IN THE REACTIONS OF 4°Ca + 248Cm and 18 248 0 + Cm.

Nucleon transfer reactions for products below the target 248 Cm (Zprocjuct < 96) were investigated in reactions of 40Ca + 248Cm and 0 + Cm at projectile energies 1.0 to 1.24 times the Coulomb barrier. Target-like products (isotopes of Am, Pu, Np, U, Pa, Th, Ac) were radiochemically isolated (Ref.1) and measured by Y~^ay spectroscopy. The cross sections in the reac- 40 248 tions of Ca + Cm are in the order of 10-100 ub for isotopes of Am. For products of the other investigated elements the cross sections are smaller and only upper limits can be given. These limits are 10-100 times lo­ wer than cross sections observed at similar projectile 48 248 energies in reactions of Ca + Cm (Ref.2), and re- actions of Xe with different actinide targets (Ref.3). The evaluation of the cross sections in the reactions of 1 R P 4 R 0 + Cm is still in progress. The results will be presented at the conference.

Ref. 1 M. Fowler et al., to be published

Ref. 2 H. Gaggeler et al.; Phys.Rev.C, in press Ref. 3 A. TUrler et al., to be published

* also affiliated with Swiss Reactor Institute at CH-5303 Wiirenlingen, Switzerland

- 36 - R. Korteling, R- Green, J- D'Auria: Chemistry Dept, Simon Fraser Univ. Burnaby, B.C. Canada V5A 1S'6 R.L. Helmer, K.P. Jackson: TRIUMF, Vancouver, B.C. Canada V6T 2A3 S. Kaufman, B. Wilkins: Physics Dept, Argonne Natl. Lab. Argonne, 1L USA 60439 THE STUDY OF COMPLEX NtfCLEAR REACTIONS BY CORRELATING FRAGMENT EMISSION WITH OTHER PARTICLE EHISSIOH USING 300 Mel' PROTONS ON BE AND AG,

A central question in explaining the mechanisms of intermediate energy complex reactions is whether the reaction proceeds primarily through a statistically emitting source at or near equilibrium, or by an ensemble of mainly direct interactions followed by final state interactions. The low energy part of inclusive fragment spectra can be explained by proposing the emission to be from a series of statistically emitting sources -which is consistent -with the reaction proceeding through an equilibrated state. Some measurements of excited state populations of emitted fragments in heavy-ion reactions support such a model. How­ ever, detailed study of inclusive spectra show inconsistencies and the total spectra can not be completely explained with such a mechanism. Recently, correlation studies, in which fragment emission is measured in coincidence with a high energy proton believed to be the incident projectile, have indicated that a direct interaction component is also present. This is most clearly seen in the increased coincidence rates at or near the QTBS angles (the coincidence angle at which there is a minimum momentum transfer to the rest of the system).

A recent correlation study, where light fragment (A < S) emission in. coincidence with proton emission was measured, added new information relevant to this general question. Be and Ag targets were bombarded with 300 HeV protons and the (p,pX) reactions were studied as a func­ tion of emission angle using a variety of Si, Nal and plastic particle telescopes at the TRIUMF accelerator. The main features or the exclu­ sive fragment spectra will be presented and compared with inclusive spectra.' The results will be discussed in terms of possible emission mechanisms.

- 37 - W. T. Porile, A. Bujak, D. I>. Carmony, Y. H. Chung, L. J. Gutay, A. S. Hirsch, M. Mahi, G. L. Paderewski, T. C. Sangster, R. P. Scharenberg, and B. C. Stringtellou Departments of Chemistry and Physics, Purdue University, W. Lafayette, IN 47907 USA

FRAGMENT EMISSION IN THE INTERACTION OF XENON WITH 1-28 GEV/C PROTONS

The emission of nuclear fragments wi rh 2 _^_ '/. <_ 14 in rh** inter­ action of xenon with 1-28 GuV/c protons has been studied by use of hybrid gas—silicon counter telescopes at 45° and 135° to•the beam. The experiment was mounted at the Brookhaven AGS and used the internal proton beam interacting with a pulsed xenon gas jet target. Events were tagged with the proton beam energy, penaitting a nearly continuous record of the interactions in the above energy regime.

Results have been obtained for the charge yield distribution and the fragment kinetic energy spectra. The data will be interpreted in terras of models of nuclear fragmentation, in particular, in terms of the thermal liquid drop model previously proposed by our group.'1)

This work was supported by the U.S. Department of Energy.

K A. S. Hirsch, A. Bujak, J. E. Finn, L. J. Gutay, R. W. Minich, N. T. Porile, R. P. Scharenberg, B. C. Stringfellow, and F. Turkot, Phys. Rev. C29, 508 (1984).

- 38 - Arthur C. Wahl

Department of Chemistry y«asiiiiagi£oia University St. Louis, MO 63130, U. S. A.

NUCLEAR-CHARGE DISTRIBUTION NEAR SYMMETRY FOR LOW-ENERGY FISSION REACTIONS

The systematics of nuclear-charge distribution near symmetry derived from experimental data for thermal- neutron-induced fission of 23:>U * are extended to other low-energy fission reactions and compared with available data. For thermal-neutron-induced fission of ^-"U and

239pUj data from LOHENGRIN measurements^' •* are consistent with systematics that are similar to those derived for 235[j, For spontaneous fission of "^Cf, jt is shown that the systematica for the lighter nuclides as represented by the Zp model need to be modified. Calculations with the Ap' model for "^Cf give reasonable systemtatics that indicate the yield for symmetric charge division (Z-49) is very small, probably even less than the small yield deduced previously from x-ray measurements.

1. A. C. Wahl, Phys. Rev. C 32., 184 (1985).

2. U. Quade, Thesis, Munich (1983). (Personal communication from J. Blachot)

3. C. Schmidt, A. Guessous, J. P. Bocquet, H. -G. Clerc, R. Brissot, D. Engelhardt, H. R. Faust, F. Gonnenwein, M. Mutterer, H. Nifenecker, J. Pannicke, CH. Ristori, and J. P. Theobald, Nucl. Phys. A 430, 21 (1984).

4. W. Reisdorf, J. P. Unik, H. C. Griffin, and L. E.

337 GLendenin, Nucl. Phya. A JT7' t <19?0. - 39 - Yuich Halsukawa, Masaaki Magara, Tsutoau Otsuki, Keisuke Sueki, Hiroaichi Nakahara, and Isao Kohno*. Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Fukasaua, Seiagaya, Tokyo 158, tCyclotron Laboratory, The lnstitue of Physical and Cheaical Research, Vakoushi, Saitaaa 351-01.

DECAY PROPERTIES OF LIGHT EINSTEINIUH ISOTOPES < AS247)

There are only limited information on the decay properties of new iron-deficient einsteinium isotopes with AS247*'^>3) By using heavy-ion reactions, we produced light einsteiniua isotopes and investigated their decay properties. As reaction systeas, we chose

12c+237Np and 14N+238U> and ieasured Es isotopes with AS247 by Beans of a-ray spectroscopy. Beaa energies were E|aD (**C)=67-81 MeV, and Elab (,4N)=80-103 MeV. The reaction products recoiled out of the target were stopped in a fast flowing heliua gas streat ( a He-jet systea ), and transferred onto the collecting tape. After an appropriate collection ( generally 8 or 3 Bin. ), the deposited recoil atoas were aoved to face Si(Au) surface barrier detectors for a-ray aeasuraents. In the 237^+12^ SySteas, *™Es was gainly observed, and 245-247gs jsotopes were observed by boabardaents of the 238U+14N ionSm Tne a|pha-peaks at 7.73, 7.36 and 7.32 MeV which had been assigned to 245gSf 246gs and 247gs> respectively, were observed. However, some other a-peaks were also observed, which, froa their energies and half-lives, could not be assigned to any of the nuclei produced by **N on Bi or Pb, possibly included in the targets as iapurities, or those produced by the transfer reaction of targets. These a-peaks were grouped according to their half-lives and the projectile energy dependence, and, the preliminary results suggested that 245Es emitted five different a-rays, 7.77, 7.73, 7.71, 7.67 and

7.62 MeV, and that 246gs na(j f,wo jS0Ber states, one of which eaitted four and the other two a-rays. References 1) V.L.Mikheev, V.l.llyuschnko and M.B.Miller: Sov. J. Nucl. Phys., §, 35, (1967). 2) P.Eskola: Phys. Rev., £Z, 280 (1973). 3) P.Eskola, K.Eskora, M.Nuraia and A.GhiorsoI Phys. Fenn. 8. 357 (1973).

- 40 - Fan.W. Zhao.Z.Z. Sun.X.R. Mou.W.T. Ma.J.Y. y.a»g,W.V. Xie.X.J. 2hao,L.L. Institute of Modern Physics, Academia Sinica, Lanzhou, China

THE DECAY OF 73Br

The r-singles, r-r coincidence and the angular correlation spectrum at the directions of 90 and 160 have been measured for Br obtained from Zn( C,2np) and the on-line chemical separation connected to a He-jet transport system. 27 r-tran- sitions, their energies and relative antenaitiea were determined, of which 8 r-rays of 102.1, 137.2, 249.0, 345.5. 363.8, 381.5, 385-7 and 390.2Kevand three levels of 192.4, 537.4 and 574.IKev were observed for the first time. The decay scheme of 73 Br is derived on the base of the coincidence relations between the r-transitions. The experimental anisotropic A's of 0.30610.056, 0.495+0.158 and 0.6-30+0.157 between the respective pairs of r-rays of 336 and 65Kev, 700 and 65Kev, as well as 275 and 126Kev were calculated respec­ tively from the angular correlation measurements and compared with the theoretical A which varied with the multipole mixing ratio. The spin of 2/3 or 5/2 for 90.4Kev level was estimated and the parities of 90.4, 151. 426 and 790Kev levels were presumed from the logft values. %

- 41 - R.V.Bogdanov, L.V.Dondukova Leningrad State University Leningrad, USSR

THREE REDOX-FORMS OF URANIUM-234 IN BRITOLITE

As was shown before, uraniuui-23't recoil atoms in britolite (natural calciua and rare earth phosphate cili— cate) will, under certain experiment conditions, enrich the tetravalent uranium fraction, the enrichment being greater from the external zones and microdefects towards the core of the (1). This report aims at explai­ ning these facts. The experimental part included mineral dissolving under different conditions, U(IV) and U(VI) separation by a number of methods and an alpha spectro- metric analysis of the isotopic composition of uranium valent forms. A few of the data obtained in the experi­ ment are tabulated below vhere 1 Is anion-exchange chro-

Solvent and _Activit£_ratio n th f J^238u fanalysi??«?s _—»—._——with reduce. _— r -.———_' withou_ t reduce_-— r — yL*yl ' y(vi) » y.(iyl yLYil 2M HC1 (1) 1.74+0.03 0.96+0.01 0.95+0.02 1.003^0.006 2M »C1 (2) 1.74+0.03 0.99+0.01 0.98+0.03 0.99 +p.o1

1.5M H5POZt(2) 1.34+0.03 0.9710.01 0.94+0.0^ 1.02 +0.02 0.5M H2S0^(1) 1.29+0.04 0.95+.O.O1 0.97+0.02 0.99 +.0.01 0.5M HgSO^U) - 0.98+0.01 0.98+0.02 1.030+0.016 matography, 2 is precipitation of uranium(IV) by cupferron, 3 is precipitation of uraniumClV) by KI0,. The results of the "experiment show that the U(VI) fraction is enriched with uranium-234 when the mineral is dissolved In the presence of reducers, and depleted when there are no reducers. This particular result points to the presence In the mineral, apart from the (IV) and U(VI), of an intermediat redox-form of uranium the properties of which place it somewhere near pentavalent uranium. When the mineral is dissolved it turns to either the U(lV) fraction or the U(VI) fraction depending on the En medium. I P.B.BorflaHOB u irp.TpeTbH BcecoK>3Han K0H$ep6Hu;Hg no XMMHH ypaHa. MocKBa. 12-14 Hoadpa 1985 r. Te3Hcu ^oioiaflOB MocttBa, "Hayna", 1955, c.6. - 42 - N.-K- Wen, T. Sato, K. Katada, and H. Sano Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Fukasawa, Setagaya-ku, Tokyo 158, Japan

CHEMICAL EFFECT OF 6Li(n,cx)T REACTION IN LITHIUM COMPOUNDS MIXED WITH SOME IRON COMPOUNDS

Chemical effects associated with the Iii(u,u)T reaction in Li _C 0, and i.i.„CO-, ttvLKicid wiLU each o[ ic;u,t:i:^l iron coia- l 2 ** i J pounds, such as Fe(oxine)3, Fe (thiooxine)3# [Fe (edtaJH^O], carboxylatoiron(III) , were studied by means of Mtissbauer sp-ectrosco-pic technique. Not appreciable changes were found in the irradiation of (NH4)-jFe(HC0O)6-n»20 itself at 2 a neutron fluence rate of 4 x 10^2n cm~ s~l for 6 h, while 8 4 -^•M*.-V:*X.*.V* high-spin Fe (II) species were - •>"'*"-'-M>v% found in the mixture with Li2" 7 6 C_04 and Li2C03 as seen in - Fig. 1. Iron(III) citrate was (a) more easily affected by the "L ^^..—-..-^r-*;'-* 46 irradiation compared with ^ "\ iron (III) acetate and (NH4)3-J3 42 (b) Fe(HCOa)6-nH„0. No signifi­ P. _ _''*"•—*w-. 23 ,<«* cant effects were found in - t'e(oxine)-, and Felthiooxine), o 3 J H 21 mixed with lithium compounds. +Li2C2°4 The yield of Fe(II) depend on 73 the total neutron dose and the kind of iron compounds, i.e., 69 the ligands coordinated to the +Li2C03 iron atom. These results can 65 (d) be attributed to radiolytic -2 effects caused by the a and Velocity / mm a- 1 T particles emmifcted in the pig. 1 lossbauer spectra of (NH.),- Li(n,a)T reaction. Fe(HCOO) )-nH20 at 78 K . (a) Unlrra- jated, lb) , (c)and (d) irradiated.

-43- Fang, Y.B., Miao, L. , Pan, Q.Y., Jiao, "-Q., Su, S.X., institute of High. Energy Physics, Academia Sinica, P.O. Boat 918, Beijing, China

DETERMINATION AND APPLICATION RESEARCHES OF PHOTONUCLEAR REACTION: YIELDS

The yields of 82 nuclides in (r.n) , (i,p), and (»",**) reactions of 40 elements induced by 23Mev bremsstrahlung are determined by means of Ge(Li) spectrometry with

Cu(r,n) cu as reference. As a result, their sensitivities in Ge(Li) instrumental photoactivation analysis are estimated under the standard conditions. The data can be divided into 6 groups: (l)$10~8g: F, Sr; {2)> 10~8-10~7g: Ga, Rb, In, Sn, Sb, Cs, Nd, Sm, Ta, Hg; (3)>10~7-10~6g:

C, Sc, Ti, Hi, Zn, As, Zrt Nb, Ag, Cd, I, Ce, Gd, Pt, Pb; _6 5 5 4 (4)>lO -10~ g: Mg, Cr, Fe, Co, Ge, Y. Mo, Ba; (5)>10~ -10~ g — 4 Ca, Mn, Cur and (6)>10 g: Na, W. The possibility of di-and mono-standard method in multielement photoactivation analysis 45 47 64 are tested by using Ti foil( Ti- Sc) and Cu foil( Cu) as 47 the comparators. The Sc in Ti di-standard is used to 24 43 47 56 determine Na, K, Sc, and Mn which are produced by the ( TiP) reactions of Mg, Ca, Ti and Fe respectively, while the Ti and Cu are used for the (y

- 44 - Hitoshi Shoji, Yuichi Oki and Nagao Ikeda Department of Chemistry, The University of Tsukuba, Sakura-raura, Ibaraki 305, Japan

RECOIL IMPLANTATION BEHAVIOURS OF 7Be FORMED IN 12C(7,na)7Be PROCESS IN SOME METAL COMPLEX SYSTEMS

7 12 7 'i'he r-acoil behaviours of tie formed in C^f,nv.) ^e process were investigated in phthalocyanine complexes including metal-free one and some metal B-diketonates of acetylacetone and its hcaw>l©gues . in the both cases, samples were irradiated with bremsstrahlung of maximum energy of 50MeV at ~-130°C using an electron linear accelerator- In the former case, the irradiated H2Pc, MgPc, CuPc, ZnPc and PbPc (Pc: phthalocyaninato ligand) were treated by sublimation. Be-doped samples were als< prepared for all the corresponding irradiated complexes and treated in the similar way to evaluate the contri­ bution of thermal reactions during the sublimation. The 7 net radiochemical yields of BePc formed in the recoil 7 process were estimated from the difference of BePc yields between the irradiated sample and the corre­ sponding doped one. These net yields of BePc implied 7 the liability of BePc formatioii in less stable matrices In the case of metal 3-diketonate, acetylacetonates of Be(II), Al(III), Cr(III), Co(III) and tris-dibenzoyl- methanate and tris-dipivaloylmethanate of Co(III) were irradiated. The irradiated metal-diketonates were dis­ solved in cooled organic solvents containing metal ion carriers and the solution was passed through an alumina 7 column. Be yields in complex fractions were determined 7 3-diketonates of Co(III) showed much higher Be complex yields than other metal B-diketonates. In the latter systems, Be-complex formation was thought to be influ­ enced by some different factors from those in the former phthalocyanine case. _ 45 _ Y.VATANABE. K.ENDO and H.SANO Department of Chemistry, Faculty of Science, Tokyo Metropolitan University. Fukasawa, Setagaya, Tokyo 158, Japan

STUDIES ON THE CHEMICAL EFFECTS ASSOCIATED WITH EC-DFCAY OF 57Co IN Co(l11) COMPLEXES USING X,r-RAY COINCIDENCE TECHNIQUE

Chemical effects associated with the nuclear transformation have been observed in various kinds of insulators, such as metallic oxides, and coordination compounds. It has been also reported that the chemical states of ^Fe forned through the EC-decay of 57Co in in­ organic compounds are mainly governed by the local radiolytic effects

caused through the decay. The chemical states of "pe observed in emission MBssbauer spectroscopy are expected to be formed through some different paths of chemical processes following the EC-decay. In the present study, an X,r~ray coincidence technique was ap­ plied to observe an emission Mbssbauer spectrum when the nuclear decay is followed by the emission of K.-X rays. A comparison of the coincidence spectrum with the conventional enission spectrum is expected to lead us to better understanding of the role of Auger effect on the chemical states in the de-exitalion processes caused after the EC-decay.

[CoCI(Nll3)5]Cl2,[Co(H20)(Nll3)5]2(C204)3 and [CoCl^OXNHa^jXNOa^ labelled with "Co were used as the source compounds in the present study. The contribution of the random coincidence was reduced by using weak radioactivity (50-80/iCi). The observed coincidence spectra were corrected by using the conventional emission spectra for " the same compounds. The results obtained show that the chemical states formed through X-ray emission remain trivalent oxidation states. The role of Auger process on the decay will be discussed in terms of radiolytic stability of ligands and/or the neighboring chemi­ cal species.

- 46 - Li,M.X.,Sun,T.Y..,Sun,X.H.,Fu,M.,Dong.T.k.,and Zheng,M.J. Institute of Modern Physics Lanzhou, China

CHARGE DISTRIBUTION IN 'flit: U.7 MeV-HEUTRON-INDUCED FISSIOH OF 232Th: INDEPENDENT YIELDS OF ISOTOPES OF Rh, Ag, Tri, an<1 Sb 12 cumulative yields in the symmetric region and 7 in­ dependent yields have been determined in the fission of 2 32 Th irsdaeed by 1^.7 MeV neutrons with nuclear eheaioal techniques. The results are (1.5+0.7)x10~^% for 106raRh, (6.2+2.1)x10~3£ for 112Ag,< 1x10"3? for 115mIn,(8.8+3.3) x10~3? for 1l6mIn.< 1.2x10~3* for 12^nSb. (3.2+0.6)x10~2 % for 126gSb, and (3.4+0.2)x10~1| for 128gSb. Our inde­ pendent yields differ markedly from those in Ref(l). The independent yields of the present work, along with the (2) independent yields obtained in our previous work .have been used to calculate the empirical Z values on the basis of a Gaussian charge distribution function with a O" of 0.5b. No odd-even correction was applied for the calculation of the Zp values. A mean AZ (=ZP-Z1X;D) of 0.^910.25 is obtained from all Z values in the aaynime- 2*5Q trie region for the fission of -""Th induced by 14.7 MeV neutrons. Abnormal AZ values in the symmetric region seem to imply that the width of charge distribution for symmetric splits is larger than the value of 0.56, which is the generally accepted value for the low energy fi­ ssion. Reference: (1) S.A.Rao, Phys.Rev. C£(1972), 171 . (2) Li Wenxin et al., Physica Energiae Fortis Et Physica Nuclearis 6(1982),365

- 47 - T. Oatta, S.P. Oange, II. Naik.P.K. Pujari and Satya Prakash

Radiochemistry Division Bhabha Atomic Research Centre

Trocibay, Bombay~40O085t INDIA

INTERACTION OF POSITRON WITH CHARGE-TRANSFER COWH.EXES

Interaction of positron with charge-fcransrer (C—T) complexes oF iodine with benzene and pyridine was investigated using Doppler-broadened line shape analysis (DHLSA) technique .to explore the usefulness of this technique for studying charge transfer complexes* The Intrinsic momentum distribution spectra of the • — e~ pair tiiera obtained after dBConvoIutlng the annihilation spectra for detector response* The Intrinsic spectra were further analysed using PAACFIT program to resolve the various components e.g. o—, p- positron!uri, posltronium—complexes, free annihilation etc. Presence of a narrow,non-central component in the intrinsic spectra was noticed in both the cases of C— T complexes. Analyses uere carried out on the possible origin of these Bide psaks considering the potential acting on the C-T electrons.inferred from the resonance integrals of thase molecular complexes as deduced from spectroscopic obaervations • Based on these analyses and observations mede on these complexes using life—time studies reported in literature, the side-peaks were ascribed to C-T electrons that are essentially the fT -electrons from benzene and the lone-pair electrons of N from pyridine in the respective C-T complexes with iodine as the electron acceptor*

- 48 - G. ANGE1.INI, Y. KE1IEYAN, M' SPERANZA Istituto di Qiimica Nucleare del C.N.R. , C-P. 10 I-O0OltS Muni t-iot undo Sl-a^iuue (RIAIUU) ]t.u]y-

GAS- AKD LIQUID-PHASE REACTIONS OF NUCLEAR-DECAY FORMED ARY1.1UM CATIONS WITH AROMAi'IC IIYDROCARBONS.

Many reactions occur via catioiiic species winch ate ot'leii ident.ifitut as sj-ecific carbon iiun ions. These are unfortunately in most instances on.y idealized models since free; catbeniiun ions ai*o iu;vei" quite achieved, existing instead in more or less clo-** proximity of a counter ion and" within a solvent cage. Tlie^e phciion-ena mask tlieii' intrinsic pro-iei-ties to the point of casting doubts on their existence itself, particularly in the case of some highly unstable, short lived cations. One such rase is offered by aryliiun ions, whose intciiiiediacy in arciiediazoniiun ions salts deeoiujxssition has long' been debated. " 'S|x>iitarieous C decay of tritium atom in tritiated arenes affords a eonvenient- means to produce free aryliuni cations into any system of interest and to study their reactions by tracer tecluiiques. The method has been applied to gather otherwise inaccessible inforiiiation about the structural properties of nucleogenic arylium ions and their reactivity towards substituted benzenes (C,ll R, with R- II, Mi , F, CI, OMo, CF , etc.) in both gaseous and cuiidensed phase. 11K- relevant data are consistent with highly reactive aryl hmi ions, wluise int emiolecular and |>osit iojxul select i vi fry t

FISSION IN A NARROW J-WINDOW AND J-DEPENDENT FISSION BARRIERS

A method was devised for extracting fission in :i narrow J-window and the fission barrier for that particular J_-value was deduced empirically in the complete fusion reaction of the pre-actinide nuclei. The method is based on the analysis of the excitation functions of the fusion reaction and the particle evaporation reaction. All available heavy-ion fission data were analyzed by the method and the obtained fission barriers at respectively specified J-value, jJ(J), were compared with the theoretical values by the rotating finite range model [1]. We further found a smooth, practically linear, relationship among thus obtained B(J) values normalized with respect to j)(0) [2] when plotted versus J/A1'^, where A is the mass number of the compound nuclei. We interpreted the smooth relationship as the collective nature of the fission barrier at high angular momenta so that it represents the functional form of j} versus angular momentum. There are, however, no fission excitation functions available in the low angular momentum region of J/A1'3<3. It is considered to be a very crucial region for the test of the present consequence. Therefore, we carried out measurements of the fission excitation functions for the three systems; 209Bi+ll+N, 209Bi+12C, and 207Pb+ll*N. The beams were obtained from the AVF cyclotron of Research Center for Nuclear Physics, Osaka University, and the fission fragment angular distribution was measured with surface-barrier solid state detectors in coincidence with the complementary fragment in order to assure the complete fusion fission only. , Then the fission cross section was deduced by integrating the measured differential cross sections with respect to the solid angle. The excitation function of the fusion reaction was calculated by the revised Bass model [3] and the cross sections for evaporation residues were deduced by subtracting the fission cross sections from the fusion cross sections. We have the deduced the specified J-value and Ji(J) for the above three reaction systems to compared with the theoretical ones and to test the presently obtained ^-dependence of the fission barrier.

[1] A. Sierk, private communication. [2] S. Cohen and W. J. Swiatecki, Ann. Phys. (N.Y.) 22, 406 (1963). [3] R. Bass, Phys. Rev. Lett. 39, 265. (1977).

- 50 - 1 111 S. Shibata , M. Imamura , T. Miyachi , M. Mutou , 2 2 2 2 2 K. Sakamoto , Y. Hamajima , M. Soto , Y. Kubota , M. Yoshida , 3 and I. ffujj ivara Institute tor Nuclear Study, University, of Tokyo, Tanashi, Tokyo 188, Japan Department of Chemistry, Faculty of Science, Kanazawa University, Kanazawa 920, Japan 3 PHOTON-INDUCEInstitute, ofD Atomi SPALLATIOc EnergyN REACTION, KyotoS University OF Cu , Uji, Kyoto 611, Japan

Radiochemical studies on photospallations of Cu induced by bremsstrahlung beams with end-point energies of E =100-1000 MeV have been performed. Irradiations were carried out with a collimated beam from the 1.3 GeV electron synchrotron of Institute for Nuclear Study, University of Tokyo at E0=300-1000 MeV, and also with uncollimated beams from the 300 and 500 MeV electron linear accelerators pf Laboratory of Nuclear Science, Tohoku University and Electrotechnical Laboratory below 300 MeV, respectively. Formation cross sections (mb/eq. q.) of about 20 produce nuclides were estimated from the results of gamma ray measurements with a pure Ge detector. Mass yields at more than 10 end-point energies were analysed la terms of the Rudstaiu's formula , and the parameter F which is equivalent to the slope of mass yield curve was compared with those of proton and heavy ion induced 2) spallation reactions of Cu . The difference in magnitude and energy dependence of the P between photon and hadron reactions seems to be ascribed to different mechanisms of energy deposition in the nucleus.

References 1) G. Rudstam, Z. Naturf. 21a (1966) 1027. 2) J. B. Cumming et al., Phys. Rev. C 1]_ (1978) 1632.

- 51 - M P. Aagaard, K- Aleklett. B- Ekstrom, H. Gokturk. B. Fogelberg,J E. Lund, G. Rudstam, L. Spanier, and H.-U. Zwicky

The Studsvik Science Research Laboratory, S-611 82 Nykoping, Sweden

DECAY PROPERTIES AND YIELD DATA OF STRONGLY NEUTRON-RICH FISSION PRODUCTS

An isotope separator ("OSIRIS") is direct­ ly attached to the small research reactor R2-0 at Studsvik- It is used for the study of fission products with half-lives down to about 0.1 s. The experimental program includes, among other things, characterization of new nuclides, measurements of energy spectra and branching ratios, of delayed neutrons, detailed nuclear spectroscopic studies, determination of total beta-decay energies, determination of absolute branching ratios of important gamma-rays in the decay of short-lived fission products, and^determination of yields^at thermal fission of U and fast fission of U. Xn the present contribution we present original data on half-lives and/or Qg-values for isotopes of (A=74-78), (A=75-80), CA=77-81), cadmium ~(A=123-130) , and indium (A=123-131). These mass regions are of special interest as they are in the vicinity of the r-process path. A set of absolute branching ratios for gamma-rays used in abundance measurements as well as the yield pattern in the thermal-neutron induced fission of U will also be described. Some experiences with a rapid chemical separation apparatus, based on thermochromato- graphy, which is attached to the collector end of the OSIRIS isotope separator are also described.

- 52 - Wei-Zhi Tian, M. D. Glascock Institute or Atomic Energy., Beijing, P.O.Box 2?^ People's Republic" of China Research Reactor Facility, University of Missouri, Columbia, HO 65211, U.S.A. UTILIZATION OF A BORON IRRADIATION ViSSEL FOR NAA IN THE DETERMINATION OF (% FOR 29Si(n,p), ^Cl(n.p) AND ^Jlntfl.p) KEACTIDNS

Past neutron flux distribution in the Row #1 pneumatic tube position at the University of Missouri Research Reactor MURR has been proven, to be close to the pri­ mary fission neutron spectrum by using nine reactions with well established s. Fast neutron flux under routine operation at 10 MW has been determined to be (6.60 * O.23)*10 n/cmVs. With this verification and determination, a project is being launched to determine a series of Of values for reactions important in NAA. As the first part of this, Of for ^SiCn.p), ^"Cl(n,p) and Zn(n,p) reactions have been determined to be (3.OI ± 0.23) mb, (0.22 i 0.02) mb and (0.96 ± 0.1^) mb, respectively. Literature values are also listed for coBsparison.

- 53 - H.M. Xu and U .

ON NUCLEAR TEMPERATURE MEASUREMENTS AND FEEDING FROM VAHViCLE ViNbOUNu S'CMES

Recently, information atout the energy densities or "temperatures" of highly excited nuclear systems has been extracted from the relative populations of excl ted states of emitted fragments.l' *' * Temperatures, T2 1 MeV were extracted from the relative populations of high lying, particle unstable states of 'Li and *H for l "N induced reactions on '"Au at 490 MeV.s In contrast, vary low temperatures TS1 MeV, were extracted from the yields of Y-ray transitions from low lying statesln Li and Be nuclei emitted in •N induced reactions on Ag 1000 500 at the same bombarding _ 1200 400 1 'be 400 energy. in order to (0 4J9 •, >) address whether (0 9B1 -JI) sequential decay 50 processes strongly 2S '""~V*^ influence the yields z 300 ^n^mM^ O of low lying Y-ray O transitions, we have (2 154 -l 740) (3B54 -3 684) seasur-ed cross a&stlana for discrete Y-ray T transitions in 'Li, Be, ,0 l0B, and l'C Wh^J^Z 400 500 200 300 fragmentation products E (KeV) emitted In ,2S induced reactions on Ag at 720 MeV. When sequential feeding is neglected, temperatures of .6±. 1, 1.0± .3, 1. Si. ** and 1.6±.2 MeV were extracted 7 from Y-^ray transitions, Be( .129 MeV - g.s). •LK.981 MeV -g.s.), 1 °B( 2. 1 51 MeV * 1 . 710 MeV), and ,JC(3.851 - 3.684 MeV), respectively These temperatures increase with the excitation energy of the excited state. This would be expected if sequential decay is Important. Thermal calculations, which Include sequential feeding, support this Interpretation. 1) D.J. Morrissey, et.al., Phys. Lett. B. 18 (1981) 123 2) J. Pochodzalla, et al., Phya. Rev. Lett. 55 (1985) 177 3) C.B. Chitwood, et al., Phya. Lett. B, in press.

- 54 - 2. Actinide Chemistry and Chemistry

of Nuclear Fuel Cycle

- 55 - L. Koch. k. Molinet Commission of the European Communities, Joint Research Centre, Karlsruhe Establishment, European Institute for Transuranium Elements, Postfach 2340, D-7500 Karlsruhe, Federal Republic of Germany 2". Adaciai delegated from Japan Atomic Energy Research Institute, Tokai Research Establishment, Tokai-Hura, Naka-Gun, Ibaraki-Xen, Japan

ALKALINE-AMERICIUM-LANTHANIDE-SEPARATION (ALAS) tip and, Am are the most abundant alpha-emitting actinides in high level radioactive reprocessing waste. Their re­ moval would considerably decrease its long-term toxicity. While tip can be' easily removed in the PUREX process by the change of its oxidation states. Am is separated from trivalent lanthanides as a trivalent ion by multistage chromatographic* processes. In alkaline solutions {1}. however, the higher oxidation states of Am are stable. Hence an alkaline extraction is proposed, by which tri­ valent lanthanides are separated readily from pentavalent Am.

Am is oxidized by known procedures. Any hexavalent Am will be adjusted to the pentavalent state during the proposed process. In order to prevent hydroxide precipitation the actinides and lanthcinides are kept in solution by complexing with EDTA. The trivalent actinides and lan­ thanides are extracted under these conditions b/ TTA/CHC1- at pH = 14. At concentration levels of 0.5 m^ Am/ml 95 % of Am and less than 1 % of lanthanides are retained in the aqueous phase during a single extraction step. The small amount of Am extracted is mainly in the trivalent state, therefore a more careful adjustment of the Am valency will improve the separation.

Literature {1} V.F. Peretrukhin and V.I. Spitsyn, Izvest. Akad. Nauk. SSSR, Seriya Khimicheskaya 4, 826, (1982) - 56 - Takao 01 and Hidetake KAKIHANA Department of Chemistry, Sophia" University, 7—1 Kioicho, Chiyodaku, Tokyo 102, Japan

THEORETICAL AND EXPERIMENTAL BASIS FOR CHEMICAL ENRICHMENT OF URANIUM ISOTOPES

Chromatographic separations of uranium isotopes have been intensively studied in our group for more than 30 years. Separation CiivjLocsi in iioiue. cUromato

Uranyl chloride 1.000025 25 Uranyl acetate 1.000088 25 Uranyl lactate 1.000142 25 Uranyl malate 1.000218 25 Uranous lactate % 1.000082 30 Table 2. Values of Uranous malate 1.000083 30 In {RPFR) of hydrated uranyl ion at 25°C. U(iV)-u(VI) redox 1,00078 30 70 1:00072 UCL* 0.001220

0-235 is preferentially fractionated UO.(H 0)^+ 0.001887 into complex species, aqueous species 2 n2 4 and U(VI) in uranyl systems, uranous UO (H 0)^+ 0.002003 systems and redox systems, respective­ 2 2 ly-

- 57 - A. R. Flambard, i-L-U- Fusban, Ch. D. Keillng, Maa 3ia-jun* and G. Marx

Department of Radlochemistry, Institute of Warcjantc & Analytical Chemistry Free University of Berlin, FabeckstraGe 34-36, O-tOQO Berlin 33, Federal Republic of Germany.

THE MIGRATION AND SORPTION PROPERTIES OF ACTIN1DES AND QThER RADIONJCODES IN CX3NCENTRATED SALT SYSTEMS UPON GEOLOGICAL MATERIAL TAKEN FROM A DEEP SALT ENVIRONMENT

The solubilities of the actinides neptunium(V), plutonium(IV) and americi- um(lU), as well as iodine (as iodide and iodatc), cesium and uranium wpre determined in various concentrated salt solutions (including saturated rock salt solutions as well as a quinary salt solution derived from oceanic salt deposits at its invarience point 0), together with their tendency towards the farmatico of colloids. Furtiier studies concemiirig the leaching of radionuc­ lides (plutonium, amertcium, cesium, antimony, ruthenium, and stron­ tium) by these salt solutions from various forms of Intermediate Level Waste conditioned in cement and bitumen have also been undertaken. Equilibrium solutions containing these elements have been passed through columns filled with natural rock salt in order to gain information concern­ ing radionuclide mobility and retardation in the unlikely event of the failure of a waste repository in a salt environment. Supplementary investi­ gations have also been carried out involving st; tic batch-type experiments, whereby the sorption of radionuclides upon salt, cement degradation prod­ ucts and iron corrosion products have been determined. Radionuclide solubility and waste-leaching experiments have indicated a strong dependence of actinide solubility upon solution pH ; equilibrium con­ centrations varying by a factor 10* over the pH range 1.0 to 10.0. Ultra­ filtration tests have indicated the presence of relatively little colloidal material for investigations carried out with pure systems, although for the natural and vraste systems cvWence of pswffo- Xor "carrier") colloids was seen. Radionuclide mobility studies have indicated the presence of at least two types of species to be present for all nuclides investigated ; one migrating with approximately the velocity of the solvent front and the other strongly retarded. Solution pH was found to exhibit a profound influence upon mobility characteristics and relatively high actinide mobilities were observed even at pH 12.0. Of the fission products, cesium was found to be the least retarded ; this effect being more pronounced in the case of bitumen leachates. Ruthen­ ium in particular, was found to be strongly held when derived from a bituminized waste •; experiments showing this to be a result of strong sorp­ tion upon the salt itself rather than upon impurities within the salt. Batch- type sorption experiments .have shown the sorption of radionuclides upon cement and iron corrosion products to be appreciable in comparison to sorp­ tion upon salt, underlying the importance of technical barriers in waste repository design.

* Visiting Scientist from the Department of Nuclear Science, Fudan University, Shanghai, People's Republic of China. - 58 - jess H. Cleveland, Kenneth L. Nash, and Terry F- Rees U.S. Geological Survey P.O. Box 25046, MS 412 Denver, Colorado 80225 USA

GEOLOGICAL DISPOSAL OF ACTINIDE - CONTAINING NUCLEAR WASTE: A CHEMIST'S VIEWPOINT

Research at the U.S. Geological Survey' cm the geochemistry of actinide elements in ground waters has demonstrated the influence ot redox chemistry, complex formation, nnd Ionic strengtf> on the solubilities of these elements. More importantly, this work has raised serious questions about the applicability of transport models based on thermodynamic parameters alone in predicting solubility and migration of these elements. For example, the solubility of plu- tonium(IV) In fluoride-containing ground waters is greater than would be predicted from the stability constants of the appropriate fluoro complexes, suggesting that the thermodynamic data are incom­ plete or inaccurate, that the system was not at equilibrium, or both. Data do not exist on all of . o possible fluoro complexes, particu­ larly for mixed specif', r»!•-•: as ^ydroxyfluoro complexes. Moreover, experiments using dif«; '. •': c ii\f~?al oxidation states of plutonium at different temperatures indicate that many of the systems - even under static conditions - are klnetically controlled and are not at equilibrium. These conclusions suggest that even if all necessary data were available, models based entirely on thermodynamics will be severely limited; they must also account for kinetics and for effects result­ ing from the changing composition of the ground water and the rock surfaces which it contacts. Incorporation of accurate kinetic terms in a model may be difficult because of sensitivity to minor changes in temperature and to the presence of catalytic impurities in the gr»«n»i vater. In any case, predictions baaed on modeling «111 be subject to large degrees of uncertainty and must be verified under realistic conditions. We propose that instead of using field data merely to verify modeling predictions, an alternate approach would be to perform site- specific empirical experiments at an early stage in the site-selec­ tion process. All other factors being equal, a site with ground water in which plutonium, for example, is inherently insoluble is clearly preferable to one with ground water imuhlch plutonium is more soluble. Laboratory experiments using actual ground waters from candidate sites are a simple, inexpensive approach to prelimin­ ary screening, and when warranted, .can be supplemented with in situ tests. Sites that survived this preliminary screening could then be subjected to more realistic transport modeling using models that incorporate both thermodynamic and kinetic terms. This approach would appear to result in a more accurate and more defensible site- selection process.

- 59 - Zheng, Q. K., Wang, Z. L., Pan, X. X., Tang, F. X. Fudan University Shanghai, P. R. C.

LUMINESCENCE DECAY OF THE EXCITED URANYL ION IN PERCHLORIC ACID SOLUTION

The lutiiinescence decay and tirne-resolved luminescence spectra of the excited uranyl ion in perchloric acid solution Siave been studied with a pulsed nitrogen laser and boxcar integrated averager. The luminescence decay depends on tlie concentration of U(V1) and the pH of the solution. While the U(VI) concentration is less than 10 mol-din , the luminescence decay is single exponential from pH 1.5 to 4.0, the lifetime is about 2.5 yus and no pH effect is observed. While the U(V1) concentration is -3 -3 higher than 10 mol*din , the luminescence undergoes biexponential decay, and a longer lifetime component is also found. Tine-resolved luminescence spectra with delay time of 0.5 and 20 /us reveal that the biexponential decay could be interpreted in terms of the deactivation of the excited uranyl aquo-ion and the hydrolysis product of U(VI).

60 - HALLA£E_J!L. SCHULZ. Rockwell Hanford Operations, Richland. Xashlngton. 99352. USA

E. PHILLIP IIORKITZ, Argonne National Laboratory. Argonne, Illinois, 6W3?» USA

THE TRUEX PROCESS*. A NEV DIMEUSION IN MAMAGFMEMT AW DISPOSAL OF LIQUID 1RU WASTES

Neutral monofunctlonal organophosphorus reagents [e.g., dl-nrbutyl- phosphonate, trl-oroctylphosphlne oxide, etc.] do not extract trf- valent activities \.0>J> VINC^ solutions. This behavior prompted Slddall and others to synthesize and test various b1functional organophosphorus reagents for their ability to extract +3. as well as +4 and +6. actlnldes from HNO. solutions. Sustained Interest In the extraction properties of blfunctional organophosphorus extractants reflects the importance of practical TRU (transuranium) waste management concerns. Removal of TRU elements, particularly Ann from many nuclear liquid waste solutions converts such solutions from a TRU-type (i.e., >I00 nCI TRU elements per gram) waste requiring expensive deep geologic storage to a low-level waste which can. In many cases, be disposed of in Inexpensive near-surface facilities.

The TRUEX (Jjransu rani urn Extraction) process recently discovered and developed at the Argonne National Laboratory (AND uses as an extrac- tant a solution of octyl(phenyl)-N,N-dI1sobutylcarbamoylmethylphosph1ne oxide (hereafter CMPO) In TBP and a normal or chlorinated parafflnlc hydrocarbon. TBP serves as a diluent modifier to pievent formation of a second organic phase under certain process conditions.

The 1RUEX process Is a highly flexible solvent extraction process capable of removing all +3, +4, and +6 actlnldes from any strongly acidic (e.g., >0.5M HN0\ or>6y.HCl) nuclear waste solution. Thg TRUEX process provides excellent decontamination of actlnldes from most common metallic and nonmetalllc Impurities. In HNO^ systems, dilute UNO, solutions strip +3 actlnldes from the CMP0-1BP solvent while dilute HNO3-IIF solutions strip both +3 and +4 actlnldes. Dilute NaoCOo solutions strip U(VI) from the CMPO phase and also serve to wash TBP andCMPO degradation products from the TRUEX process solvent. The TRUEX process solvent is very resistant to both chemical and radlolytlc degradation.

The TRUEX process 1s the most exciting and potentially useful nuclear separations process to be developed since the PUREX process In the 1950's. Rockwell Hanford and ANL Investigators are developing and testing IRUEX process flowsheets for removal of TRU elements from several Hanford Site wastes Including Plutonium Finishing,Plant and complexant concentrate wastes. The TRUEX process also appears to be well-suited to removal of plutonlum and Am from certain aqueous chloride wastes generated during pyrochemlcal plutonlum processing operations.

- 61 - H.-J. Bleyl, H. Goldacker and H. Schmieder InstiTuTTUr Itelsse Chemie, Nuclear Research Center, P.O.B. 3640, D-7500 Karlsruhe, Fed. Rep. of Germany

ACTIVITIES IN AND RESULTS OF THE IMPROVEMENT OF THE PUREX PROCESS

At the Karlsruhe Nuclear Tiosearch Center development efforts were concentrated on the liquid-liquid extraction for reprocessing of spent nuclear fuels. A number of Purex test facilities of laboratory scale as well as pilot plant scale was built offering the possibility to develop the process and its equipment. The major goal throuahoiit the past years were process optimization with respect to a high product yield and high separation efficiency for fission products and simpli­ fication of the process chemistry and process technology. The work in­ cludes light-water reactor as" well £s fast-breeder reactor fuel repro­ cessing. The paper reviews the test facilities and gives results of improving the Purex process.

- 62 - A. Hoccia ENEA FUEL CYCLE DEPT. - CRE CASACCIA - ROME, Italy

PROGRESS IN NEW SOLVENT DEVELOPMENT FOR HIGH BURNUP LVIR AND FBR FUEL REPROCESSING

New types of solvent, to be used in spent fuel reprocessing were sometime proposed, receiving very moderate considera­ tions of possible introduction in plant practice. Amidic solvents, studied in ENEA laboratories in the last decade,show to have better performance and major chance to contribute to a substantial process development. Many possibilities to introduce this type of extractants are given, ranging from a simple substitution of the well known TBP, to the adoption of new processing schemes. Related new concepts are the suppression of any kind of reductant, based on the Higher selectivity of the amides (Fig.l), and the possibility to have a mixed U-Pu final product, without splitting the process on two separate lines of different capacities and features. Present developments of this research line are based on the concept to limit the function of the reprocessing plant to the codecontamination, modularly iterated until matching the wanted product activity rate and purity from contaminant ions. The enrichment step, to be carried out with a highly selective solvent in a compactly sized equipment, is considered as an automatically controlled step, previous to the conversion operation. Principal results obtained until now are illustrated and discussed.

- 63 - L.G. Barreta and A.V. Bellido Instituto de Engenharia Nuclear, Comissao Nacional de Energia Nuclear. C.P. 2186, 20001 Rio de Janeiro, Brasil.

HYDFOLYTIC AND RADIOLYTIC DEGRADATION OF TRP IN SYSTEMS

TBP, 3 0% (v/v) - DODECANE/H20 - HN03 - U02(N03)2

The hydrolytic and radiolytic degradation of tri-n-butyl phosphate tfas investigated in two-phase systems of four different uranyl nitrate concentrations, ranging from 0.6 M to 1.5 M, in which the nitric acid concentration was made to vary from 0 to 3 M. The systems were irradiated with G0Co gamma rays in doses up to 10 Wh/£. The TBP degradation was measured by determining, after methylation, the di-butyl acid concentrations by gas- chroma tography. Data obtained have shown that hydrolytic degradation is a result of a combined effect of the U02(N0_)_ and HNOg, being the former more - important because its preferential extraction to the organic phase. The HDBP concentration increases directly with the UOjCNOOj and HM03 concentrations when, in turn, one of the compounds remains at constant concentration. Radiolytic degradation, for doses greater than 1 Wh/fc, increases with the dose absorbed by the system and with independence of the U02(N03)2 concentration. At smaller doses, the UNO- modifies the linear relationship. Data and interpretations will be discussed.

- 64 - F. David , K. Samhoun , R.W. Lougheed , R.J. Dougan , J.F- Wild , J.H. Landrumcl, A.D. DouganC*, and E.K. Hulet° a) Laboratoire de Radiochimie, IPN, 91406 Orsay Cedex CFrance) b) Lebanon CNRS, Beyrouth (Lebanon) c) Lawrence Livermore Laboratory, Livermore, California (USA)

PHYSICOCHEMICAL PROPERTIES OF NOBELIUM

Since some accurate experimental data are now in the lite­ rature, we can provide the systematics of lanthanide and actinide properties. We will present an evaluation of many of the main characteristics of the element nobelium and its ions : the radius and entropy of the divalent metal, subli­ mation enthalpy, crystallographic radii of divalent and trivalent ions and enthalpy of hydration and entropy of the aquo ions.

In order to obtain the redox behavior of nobelium, we have measured the amalgamation potential of nobelium.Radiocoulo- metric experiments were undertaken in the presence of both weak (acetate) and strong (citrate) complexing agent. Seve­ ral hundreds of 259^0 atoms were produced at the 88-inc. Cyclotron at the Lawrence Berkeley Laboratory by the 243cm ( 180, ot 3n) reaction.

The half-wave potential corresponding to the No — No(Hg) reaction was measured. Af*ter correcting for the amalgamation energy, we deduced redox potentials for the 2/0 and the 3/0 couple.

Nobelium is the heaviest element where experimental thermo­ dynamic data are available. This fact emphasizes the advan­ tage of radioelectrochemical methods. We have used addi­ tional data obtained with transcalifornium elements to com­ pare the redox potentials at the end of the actinide. The large differences between lanthanides and actinides might be attributed to increased relativistic effects as the end of the periodic table is approached.

- 65 - W.U C.C., Tiu, Y.F.. Jiang, L.G. Department of Technical Physics, Peking University fipi.ji.ng, China

A STUDY OF THE RECOVERY OF NOBT.E METAIS RHODIUM AND PALLADIUM FROM REPROCESSING WASTES OF NUCIEAR FUEL

In order to separate Rh and Pd from reprocessing wastes of power reactor nuclear fuel, Rh and Pd were precipitated in metallic form through formic acid denitration process. Under the optimum technological conditions of the formic acid denitration we have developed, the acid concentration of the solution was reduced from 3.52M UNO3 to pH 2, Fh and Pd almost quantitatively precipitated, and transplutonium and. rare earth elements remained in the solution.

Taking solvent extraction as the fundamental process, Rh and Pd were subsequently recovered from the, solution of the precipitate. The recovery of Rh and Pd exceeded 90% in the whole process. The chemical purity of the final products Rh and Pd exceeded 99.9% and 99.95% respectively. Pd was not contaminated by some major long-lived fission products, e.g., 90Sr/9°Y, 1(*Ru/106Rh, 125Sb, 137Cs, ^Ce/^Pr and Em. No -^'Cs contamination in Rh could be detected. The decontami­ nation factors of Rh for 90Sr/90Y, 106Ru/106Rh, ]25Sb, ^''Ce/^Pr and 147Pm were 2.4xl06, 5.2x10^, 9.0xlo\ 9.6xl06 and A.lxlO6, respectively. After further purification by adding holdback carriers, the decontami­ nation factor of Rh for 1O6Ru/106Rh reached 6.2xl07, and complete decontamination wns obtained for Rh from the other nuclides mentioned above.

- 66 - ,Li Xj.nq-fu.Guo Ao-ling.Liu Li,Feng Xi-zhang,Xu Ying-ting Application department,The institute of High Energy Physics, Academia Sinica,Beijing,P.O.Box 2732 Sun Peng-nian Biology Department,the University of Science and Technology of China

MATCHING OF COORDINATION SITES WHH LIGANDS

7hc Coordination space,with the solid angle of 6TT,may bo resolved into different coordination sites according to the required symmetries.The stable structures exist only when the sites fit well with the sizes and the shapes of the ligands.This principle help: to understand many problems in actinide coordination chemistry so far unclarified.

For example,disproportionation

2L!Cp2Cl2 thf UCp3Cl + UCpCl3thf e occurs because the largest vacant site in UCp„Cl„ is 30 which is only 4 less than the FA of the solvent.By changing into the products structures,two thf moleculars have got properer coordination. 0 30* ___ 36 thf thf

44 CI CI -4- CI CI thf 034* )_ 44 CI 44* CI CI CI 55* C£Cp_ Cp_ Cp_ 55 fjp_ fjp_ CJJ 55 Cp_ c,„ + c,.. . Td + Oh

- 67 - K.H. LIESER Fachbereich Anorganische Chemie und Kernchemie Technische Hochschule Darmstadt, D-6100 Darmstadt, FRG

CHEMISTRY OF TECHNETIUM AND NEPTUNIUM IN THE NUCLEAR FUEL CYCLE

The interest in the chemistry of the radioelements technetium and neptunium has increased appreciably during the last years. 99TC and 2^7Np are produced in nuclear reactors (about 0.7 -and 0.5 g per kg of U, respectively) and have long half-lives. The highest oxidation state of both elements is +7, but the chemistry of Np is more similar to that of U and Pu. The stable dioxides* Tc02 and NpC-2 are obtained after heating of various compounds at higber temperatures. In aerobic acid solutions, Tc04~ is the most stable form of Tc, whereas Np may exist in the oxidation states +4, + 5. or +6, depending on the redox conditions. In the case of Np, disproportionation of Np(V) plays an important role. In the course of reprocessing of nuclear fuels, Tc and Np may be found in various process streams. TcC>4~ is partially extracted from nitric acid solutions by TBP as HTc04(TBP)m (in absence of uranyl ions) or as UO2TCO4NO3 (TBP) 2 Q,r U02(Tc04>2 (TBP) 2 (in presence of uranyl ions), depending on the relative concentrations. Tc(VII) is not reduced by iron(II) sulfamate, but by hydrazine, by U(IV) and also under the conditions of electrolytic reduction. Tc(IV) is found in the aqueous , phas together with Pu(III). The plot of the distribution coefficients of Np(lV), Np(V) and Np(VI) .between nitric acid solutions and TBP in n-dodecane vs. HNO3 concentration shows highest values for Np(Vi), medium values for Np(IV) and very low values for Np(V). The disproportionation of Np(V) into Np(IV) and Np(Vl) depends strongly on .the acid concentration and also on the stability of the complexes that may be formed. Furthermore, disproportionation is a slow pro­ cess. Therefore, by proper choice of the redox conditions, the acid concentration and the time of equilibration, the relative amounts of Np in the aqueous and in the organic phase may be varied, either in such a way that Np is found mainly in the highly actice waste or that it may be re­ covered with high yield.

- 68 - Chen Yaozhong. Wei Liansheng, Fan Yuanfa, Jiang Fashun, Zhu Rongbao, Qiao Sengzhong, Lin Zhangji Institute af Atomic Energy, Beijing, China

PREPARATION OF CURIUH-242 OF CURIE QUANTITY

In this work, a new method of preparing 'Cm in curie *.\uaut Lty Ls reported. AmO-^ powder and Al powder were well mixed and irradiated for 9-U days at a neutron flux of 6x10 ^ neutron/cm /sec. After cooling the target was dissolved. The chemical separation of * Cm from irradiated target was accomplished via two kinds of chromatography: TBP extraction and CH3OH-HNO3 anion exchange. 1.7 curie 242Cm in CH3OH-HNO3 solution was obtained finally, the of-activity ratio of Am/Cm is 3x10" .

This process has the advantage of having less chemical separation steps so that the chemical operation is simple. Besides.it is not necessary to adjust the feed acidity during the whole process.

Acknowledgement Tan Bingmei, Zhang Xiufu, Zhao Yanju, Yang Liucheng Lie Hengjuen, Teng Yizhen, Ji Liqiang and Zhang Zengrui participated in this work.

- 69 - Y5ra Jedin&kova, ZdenSk Dvorak and Jana Xilkova

Prague Institute of Chemical Technology, Dopt. of

Nuclear Full Technology and JLadiochetfcisiry, l66 23

Prague (Czechoslovakia).

DESCRIPTION OF HIKROAMOUNTS OF AM(lIl) EXTRACTION

XN THE PRESENCE OF MACROAMOUNTS OF LANTHANIDES.

On the basis of 60 distribution dependencies, an analysis of the effect of aacroconponent (lanthanide) on the extraction of mioroeoraponent (americium) by benzyldialkylamines and benzyltrialkylanunonium salts has been made. Assuming the validity of D, = f(o. ) and D. = f(c. ), the power- function of general expression log D = log P — q log cT has been calculated, L>n the constants have been determined of the equation applying individual extraction systems and their physical and chemical characteristics have been discussed.

From the technological point of view, the px-esented method enables to simulate the purification process of maorocomponent from known dependencies DA = V°A>-

- 70 - Heino Nltsche Earth Sciences Division, Lawrence Berkeley Laboratory, University of California. Berkeley, California 94720 U.S.A.

TFArPERATURE EFFECTS ON THE SOLUBILITY AND SPECIATION OF SELECTED ACTINIDES*

In order to meet the requirements necessary to license a high-level radioactive waste repository in the United States of America, reliable predictions are required on the solubilities of actinide elements and the speciation of the solur liou couit>l«x«s tv>iikk«d vfcUlt £i\>uus\tory sue. Tke migration of contaminated groundwater is considered as one principal mechanism for the transport of radionuclides from the storage location to the accessible environment. The solubility and speciation predictions for aetinide waste elements are made by utilizing thermodynamic solution data. Since elevated temperatures are expected La the- repository and litt&r off mo> EjnEoffnaa- tion is available on thermodynamic solution data at temperatures above 25 * C, one common approach is to extrapolate thermodynamic functions to elevated temperatures from available data or reasonable estimates for 25 * C. The objective of this study was to experimentally determine the temperature dependence of the solubilities and speciation of neptunium, plutonium and americium. In groundwaters hydroxide and carbonate anions are considered to play a most important role in the formation of insoluble precipitates and soluble complexes of actinides.1,1 Therefore, solubility measurements were made in 0.01 M non-complexing NaC104 solution at pH's 6.0 and 8.5 at 25 ° C and 60 * C, respectively. The total carbonate concentration was held constant at 120 ppm, a value common to some groundwaters. This study showed no clear trend in solubility increase or decrease as the tem­ perature changed from 25 °C to 60 *C. Many of the solid phases formed, although they were crystalline, had to remain unidentified, due to the lack of reference data in the literature. A comparison of the experimental results with solubility predictions from modelling calculations showed significant differences. The differences are probably caused by the existence of unknown solubility controlling solid phases in the experiment which had to be omitted in the modelling data base. The results of this study demonstrate the neces­ sity to study radionuclide solubility experimentally in groundwaters from a prospective repository site to accurrately predict the solubility limits necessary for licensing a nuclear waste repository.

1. Determination of Radionuclide Solubility in Groundwater for Assessment of High-Level Waste Isolation: Technical Position, U.S. Nuclear Regulatory Com­ mission, Washington, D.C. (1984). 2: B. Allard, Solubilities of Aciinides in Neutral or Basic Solutions, in N. Edelstein (ed.), Actinides in Perspective, Pergamon Press, New York, 553-580 (1982). 3. R. J. Silva, " Temperature Dependence of Actinide Solubilies and Specia- ii*on," Proceedings and Recommendations from a Conference on the Applica­ tion of Geochemical Models to High-Level Nuclear Waste Repository Assess­ ment, eds. G. K. Jacobs and S. K. Whatley, prepared for the U.S. Nuclear Regulatory Commission, Oak Ridge, Tennessee (1984). *This work was supported by the U.S. Nuclear Regulatory Commission, Office of Research, Division of Radiation Protection and Earth Sciences, Washington, DC 20555. - 71 - Shoidri TAC8IM0RI Oep. Nucl, Safety Research, Japan Atomic Energy Research Institute Tokai-roura, IbaraH-ken, 319-77 JAPAN

A MATHEMATICAL MODEL OF DISTRIBUTION RATIOS TOR U(IV), UCVI), Pu(III), Pu(lV) AND NITRIC ACID BETWEEN 30 V0L.2 TBP IN N.PARAFFIN AND NITRIC ACID

A Precise model of distribution ratio of the ionic species between organic and aqueous phases is essential in simulation of counter- current solvent extraction process like PURO of fuel reprocessing, vrhich enables us designing an efficient and reliable flowsheet. Several authors have proposed the mathematical models of distribu­ tion ratios of uranium, plutonium and nitric acid in tri n-butyl phosphate(TBP) and nitric acid system. They are based on the concen­ tration equilibrium constant, free TBP concentration, ionic strength, acid concentration or concentration of nitrate ions. These trials, however, failed to good fit over a wide range of concentrations of the components between calculated and experimental values. KOLARIK and PETRICH reported ' a purely empirical expression of distribution ratios as functions of concentrations of each ions and total nitrate ions in the equilibrium aqueous solution, which improved versatility of the model in applying to actual processes. The present model is composed of similar empirical description of the distribution ratios, but formulated to have larger applicability to the extraction systems with all actual combinations of ions, i.e. U(IV), U(VI), Pu(III) and Pu(IV). The form of the expression is b m P D„ = a CN(M) /C 1 + E( PUCmi * P3l.CN(M) ^-Cnli)] where D^ is distribution ratio of M, C . is the aqueous concentra­ tion of n»|, and a, b, p^, P2j»...P4f are parameters. CN(M) is an effective total concentration of nitrate ions in the aqueous ~* phase in which Harned rule is taken into account and expressed as

3C ex (nx ) + 4t x ,( x ) CN(M) - CH + CHydr.«p(lwIIydr) • 2Cw««p(«U6) + Pu3 P PU3 V * '* W where x denotes fractions of the ionic, strength contributed by the respective components, the subscripts H, Hydr and Pu3 relate symbols to nitric acid, hydrazine nitrate and Pu(III) respectively, and k,. ni, n and q are parameters. All parameters for each equation of Du were obtained by a least square computer procedure with the experi­ mental values3)»4). The DM values calculated by the model fit well and are shown compared with experimental values. References 1) Z.Kolarik, G.Petrich, Ber.Bunsenges.Phys.Chem.,83, 1110(1979). 2) Z.Kolarik, S.Tachimori, T.Nakashima, Solv.Ext.Ion Exch., 2(4&5), 607(1984). 3) G.Petrich, Z.Kolarik, KfK 3080, (1981). 4) S.Tachimori, T.Nakashima, Z.Kolarik, R.Schuler, Kfk 3637 (1983). - 72 - RECENT PYROOHEMICAI. PLUTONIUM RESEARCH AT LOS ALAMOS

The objectives of the pyrochemlcal program at- I.os Alamoa are to develop methods to recover all the plutonium from our scrap and to convert It to high purity metal. Plutonium mptnl prpparntIon is accompli shed by TPnviction of either PuF. or PuO„ In a molten salt eutectlc. The metal is purified by nalide slagging, vacuum casting and electrorefining at elevated temperatures. The product from this integrated process is ultra high purity plutonium metal.

Our research is aimed at recovery of plutonium from process residues, "reduction of residue generation by process improvements, reduction of residues by recycle of" reagents, and optimization of all process into an integrat­ ed closed-loop system.

All of the processes are at relatively high tempera­ tures, 700 to 900 C, and all .but casting Involve molten salts. Plutonium is present In the process residues as oxides, chlorides, colloidal metal and as impute metal heels. Treatment by either aqueous or pyrochemical methods can be utilized to recover the plutonium. Proposed residue reduction and reagent recycle will significantly reduce waste handling and operating Jexpenses. Process optimization includes both revision of the existing processes and new developments through our research program.

This presentation summarizes some of our progress in these project^;.

- 73 - Zhu Yonqjun Yang Dazhu Liu Bingren Chen Jianfeng Chui Jun Institute of Nuclear Energy Technology Tsinghua University Beijing, China

THE REMOVAL OF ACTINIDES FROM HIGH LEVEL RADIOACTIVE WASTE BY TRPO EXTRACTION THE EXTRACTION OF AMERICIUM AND SOME LANTHANIDES FROM NITRIC ACID SOLUTIONS

Lonq lived a-emiltinq actinides are the main source of long term radioactive hazard of high level waste arising from the reprocessing of spent nuclear power reactor fuels. The removal of actinides, including trivalent amerieiura, from high level waste is important for the safety feature of nuclear fuel cycle.

TRPO, a mixed trialkyl phosphine oxide, has been proved to be an effective extractant for the removal of actinides 'from medium concentration nitric acid solutions. In this study, the distribution ratios of trivalent Am, Eu, Nd and nitric acid between 30?i(vol) TRPO-Kerosene and aqueous solutions with different nitric acid and lanthanide ion concentrations were determined. Empirical equations for these distribution ratios were obtained with regressive method. Mathematical model of multistage TRPO extraction process was established and process parameters under different conditions were computed. Several results were checked experimentally using micro amount Am-241 and mini-annular centrifugal extractors. Results show that the recovery of Am and Nd by 30?o TRPO extraction is higher than 99.9% from synthetic radioactive waste solutions containing nitric acid up to 2M.

- 74 - M- Nourmand Nuclear Research Centre, Atomic Energy Organization of Iran, Tehran, Iran

STABILITY CONSTANTS OF URANIUM(VI) AND THORTUM(IV) COMPLEXES "WITH SOME d -AM1N0-ACIDS

The formation constants of uranium(VI) and thorium(IV) complexes of some c(-amino-acids such as methionine, alanine cysteine, phenylalanine, serine, proline, threonine and tyrosine have been obtained at 25°C using potentiometric titration technique. Values for the formation constants were calculated based on equations suggested by Irving and Rossotti also from potentiometric titration curve method using a Cyber, 170 (CDC) computer.

For comparison, values for complexes of serine showed a: agreater stability than those of alanine, methionine or cysteine due tec the presence of an -OH group which showed an affinity to form an extra bond with related metal ions. Concurrently for the same reason, complexes of tyrosine are found to be higher in values than those of phenylalanine. As it appears, the complexes of these ligands with thorium ion are more stable while uranyl complexes are somehow less stable with respect to some amino-acids studied in this work. This could be explained in terms of UO.* ion being much larger Th^4".

Some suggestions also possible structures for these complexes compatible with experimental evidences is described.

- 75 - G.Harx, V.Friehmelt, R.Gauglitz, S.Kriegel and Yang Zhizhen, lie Adi, Ye Hinglu Institute of Inorg. and Analyt.Chem. Dept. of Radiochemistry, FU Berlin(F.R.G-) and Fudan University, Nnclear 6c.Dept. (Shanghai/China)

EXTRACTION PHENOMENA OF'Np, U, Nd. Ru, Zr and Cr IN FUREX- MEDIA MONITORED BY AN ANALYTICAL ULTRACENTRIFUGE

An analytical til trncenfcH Fuge wa.«? applied to investigations on the extraction of Np, Nd, Ru, Zr and Cr in presence of highly concentrated IK^NC^^-HNO-j solutions of practical impor­ tance to provide physicochemical data for optimizing the PHREX- process. In these multicomponental systems the distribution coefficients of the characteristic elements vere measured, where Np and U stood for the actinides, Nd» Ru, Zr for FPS and Cr for corrosion products. The data obtained were combined with the diffusion coefficients also determined in these media by which the speed determining step of the extraction under the practical conditions of the FUREX-process was evaluated. Using an analytical ultracentrifuge for investigating these phenomena made the local concentration profiles of those constituents under investigation be determined continuously, an advantage which cannot be underestimated. Also the investigation of the formation of complexes with degradation products of the TAP was taken into consideration,by which a new Zr(N03>2*2DBP complex was discovered, also belonging to the variety of those substances reponsible for crud formation. The influence of competing reactions upon the extraction (reduction or the extraction ratio) were also systematically investigated; The importance of those reactions upon the extractions which significantly

reduced the extraction ratio, was also taken into consideration and a reasonable compromise was found hetween the enhancement of the extraction by raising the aqueous nitrate concentration and those competition-reactions, becoming dominantly whenever a lot of salts and nitric acid was already extracted and only a small concentration of free TBP left behind lor complex formation. - 76 - Wt W. SCHUL2i Rockwell Hanford Operations* Richland, Washington, 99352, USA S. A. GALLAGHER, Rockwell Hanford Operations, Richland, Washington, 99352, USA R. D. SCHEELE, Pacific Northwest Laboratory, Richland, Washington, 95352, USA

APPLICATION OF ANTIMONIC ACID TO REMOVAL OF 90Sr FROM ACIDIC NUCLEAR WASTE SOLUTIONS

A batch sorption process, employing solid antlmonlc add ISboOj • 4^0) as the sorbent. has been formulated and partially developed for removal ar\d» 1f 'warranted, recovery of fission product Sr from the acidic high-level waste (HLW) generated during processing of Irradiated reactor fuel. This sorption scheme has been specifically tailored for possible application to the HLW generated In the U.S. Department of Energy Hanford Site PUREX plant. Removal of 90Sr from he latter waste may eventually be desirable either to facilitate Its subsequent disposal or to recover and purify "°Sr for beneficial use or both.

The strong and selective affinity of antlmonlc add for ""Sr from strong HNOj solutions is well-known; Abe has recently written a compre­ hensive review of the preparation and sorption properties of antlmonlc add. The extensive existing data base was used 1n conjunction with carefully-selected bench-scale tests with simulated and actual HLW to formulate a batch "Sr sorption process comprising the following steps:

o Batch contact (24-48 hrs at >80°C) addic (>J. .0& HNOg) HLW with solid antlmonlc acid (solid:liquid ratio = 10 g/L) to remove about 90% of the 90Sr.

o Separate, water wash, and dry the Sr-loaded antlmonlc acid.

o React (250°C) the dried solid with HC1 gas to volatilize and separate (as SbCle) antimony from 90Sr.

o Dissolve the residue of solids from the hydrochlor1nation step 1n water to obtain a small volume of "90Sr-crude concentrate11 suitable for purification by well-established cation ion exchange procedures.

This batch Process has several Important advantages for possible future removal of 90Sr from Hanford PUREX plant HLW. Among these are:

o Elimination of the need to use large amounts of organic complex- ants (e.g., EDTA, HEDTA, etc.) required 1n the HDEHP extraction process; such reagents seriously complicate further waste manage­ ment and disposal.

o Realization In one batch contact a small volume of 90Sr-loaded solid suitable for further processing In the hot cells of the existing Hanford Waste Encapsulation and Storage Facility.

- 77 - Yang Da^hu, Zhu Yongjun, Liao Shishu, Jiao Rongzhou Institute of Nuclear Energy Technology, Isioghua University, Beijing, China

THE STUDY OF EXTRACTION OF U(VI) AND PU(1V) BY NEUTRAL PHOSPHORUS - BASED ORGANIC COMPOUNDS

Severs! neutral phosphorus - based extractants with different substituent groups have been synthesized with Michaelis' method.. They are (1) (n - C.H^O^CGaHs )P0

(2) [CH3(CH^gCH(CH,)0)^(C2H5)P0

(}) (CH3(CH2^CH(CaH5)CHl0j2(C2H5)P0

(4) (CH3(CHa).,CH(CaH5)CM20]j(CHi)P0

(5) [CHsCcH a)*CH(C2H s)CH2o] a( (CHS)2CH] PO

(6) [pMClU)*CH(C2H5)OHaO]2[(CH3)iCH CH2]P0. The extraction of li(VI) and Pu(IV) from nitric acid solution by these extractants has been studied as a Function of temperature in the range of 0 - 50 C. The value of , „ _ _ rkmrl 'v r- -L L y ( 1 + £8 INOjl ) for nitrate 1 n A complexes of U(VI) and Pu(IV) in nitric acid medium f"is been determined at different temperatures. From the variation of the equilibr^ow constants with temperature the thermodynamic quantities AG, AH and AS have been calculated for these extractants. The results of this study indicate that the value of enthalpy change is negative for the extraction of both metals and the value of entropy change is negative for the extraction of U(VI) and positive for the extraction of Pu(lV). The steric effect of the substituent groups plays a major role in the difference of extraction ability of different extractants. F.xtractants with some sterically bulky groups can improve the separation of U(VI) and Pu(IV) to some extent.

- 78 - T 2. 2 2 1 Wen-Ji Wang, Peiju Zheng ', Buoyi Wang, Ming Wang and Bozhong Chen i 2 Department of Nuclear Science, Centre of Measurement and Analysis, Ftxlan University, Shanghai, China. CHARACTERISTIC AND MOLECULAR STRUCTURE OF EXTRACTION COMPLEX OF URANIUM(VI) WITH DICYCLOHEXANO-18-CROWN-6 ISOMER A

The extraction of U(VT) with dicyclohexano-T8-crown-6 ( mixed isomers or isomer A ) from HCI medium is effective and selective, and can be used for separating and analysing uranium and thorium. However, little is known of the properties of the extraction complex of uranium with crown ether in organic phase. In this paper we report the preparation.characteristic and structure of the crystalline extraction complex la - UOgClg - HCI - HgO, la being isomer A of dicyclohexano-lB-crown-6.

After extracting uranium(Vl) from aqueous hydrochoric acid solution with la in 1,2-dlchloroethane, the crystalline product of extraction complex was prepared from organic phase by diluting with non-polar solvent at 25°C The content of uranium, crown ether and HCI was determined. The IR spectrum of the crystals shows that the strong hydronium - crown ether / oxygen hydrogen bond absorption is found in the region 2300 - 2'f00 cm~ . The chemical shift in the range 9-12 ppm was observed . The Ti NMR signal of hydronium protons appears at 9.890 ppm.The results of 0 U0 C assay correspond to the formula (la)2* (H3 )2 * 2 ^f *

Crystal structure of the extraction complex has been determined by X - ray crystallography. Crystals are monoclinic, space group C2/c (N0,15) as32.W», b -10.203, c =21.616 A\/3 = 119.73° and Z = '». In the complex each of the two H~0 cations is anchored in the crown ether cavity by three stronger hydrogen bonds ( distances approximately 2.65 A* )» whereas uranium forms UOgCl^2" with CI" as counterloh about 8 A5 away from the H^O .

- 19 - Qin, Q.Z., You. J.Z., Zhou, Z.M. Department of Nuclear Science, Fudan University Shanghai, China

KINETIC. STUDIES ON THE EXTRACTION OF URANIUM (VI) FROM PHOSPHORIC ACID SOLUTIONS WITH HDEHP AND TOPO

The kinetics of extraction of uranium XVI) from phosphoric acid solutions with HDEHP and TOPO in cyclohexane has been investigated using Lewis stirred cell and rising organic drops technique. The results of kinetic measurements suggest that the extraction rate of U (VI) by HDEHP might be diffusion controlled in the 4 M H^PO, aqueous solution. However, it might be interfacial chemical reaction controlled at the 0.5 H H3P^A aqueous solution.

For the diffusion controlled system, the rate expression is found to be pseudo-first order in tU(VI)] and 3/2 order in

(HDEHP)2 respectively. The extraction rate is nearly independent on temperature.

For the interfacial chemical reaction controlled system, the rates of forward extraction (Rp) and backward extraction

(RD) are measured as a function of the concentration of + U (VI), H and HDEHP, and the rate equations can be written as

+ 1 RF=KF[U(VI)]tH r [(HDEHP)2lorg

+ 2 RB=KBfU(VI)]orgt(HDEHP)2]3/2[H ] The apparent activation energies Ep. and E„ are found to be 20 KJ/mole and A3.5 KJ/mole respectively.

There is nearly no influence on the extraction rate when TOPO is added into the organic phase over the concentration of 0.05 to 10"3M.

- 80 - Mao, J.J., Zhou, 2.M.. Qin. Q.Z. Department of Nuclear Science, Fudan University, Shanghai, china

THE STABILITY AND ABSORPTION SPECTRA OF URANIUM(III) IN HYDROCHLORIC ACID SOLUTIONS

The stability of trivalent uranium prepared by the liquid-zinc-amalgam method and the electrolytic reduction has been investigated in the air and nitrogen atmosphere. Uranium!Ill) in hydrochloric acid solution is oxidized rapidly to uranium(lV) and the oxidation of uranium(ill) in air is found to be a pseudo-first order reaction. However, in nitrogen atmosphere uranium(III) is. fairly stable and the oxidation rate increases on increasing the concentration of uranium(III), hydro­ chloric acid and some complexing agents. The autoxidation of uranium(III) in aqueous solution is discussed.

The absorption spectra of uranium(III) in 1 M and 9 M hydrochloric acid ^solutions are examined. The molar extinction coefficient of U(III) is 167 (1 mol~ cm" ) in the HCl concentration range o.5-4.5 M and U(IV) practically doe§"' not interfere in the photometric determination of U(III) at the wavelength of 521 nm.

- 81 - Chen,Yude Mao, Jiajun Fu, Ley Li, Xintai Department of Nuclear Science, Fudan University, Shanghai, china

STUDY OF THE TERNARY SYNERGISTIC EXTRACTION OF URANIUM EY CHELATE-CHELATE-NEUTRAL EXTRACTANT

The synergistic extraction of uranium nitrate using l-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (PMBP) , thenoyl trifluoyl-acetone (TTA) and tributylphosphate (TBP) in chloroform media has been studied.

It is found that synergistic effect occurs during the extraction of uranium nitrate with the chloroform solution of PMBP (HA)-TTA (HA')-TBP (B). The formation of a ternary extracted complex UO_AA'B is confirmed by usual slope methods. A method is proposed for the calculation of the equilibrium constant which is evaluated to be lgK,,.,=2.65 .

The binary synergistic extraction of uranium nitrate using PMBP-TBP and TTA-TBP has also been studied. The binary synergistic equilibrium constants are determined to be lgK2Ql=3.07(UO2A2B) and lgK021=l. 39 (UO^B) respectively.

An attempt has been made to interpret the data mainly on the basis of statistical factor.

- 82 - Yu, Y.F., He, A.D., Zhang. Z.J., Chin, C.T. Department of Nuclear Science, Fudan University, Shanghai, China

PHOTODISSOCIATION OF NITROSYL RUTHENIUM NITRATES IN NITRIC ACID SOLUTION

The photodissociation of nityrosyl ruthenium nitrates in nitric acid media is investigated using medium pre­ ssure mercury lamp, nitrogen laser and ion la£er.

This work shows that the RuNO(N03), species are sensi­ tive to visible and UV light radiation and can be photoconverted effectively to Ru(lV) with an unfiltered Hg lamp. Under given experimental condition the photo- dissociation rate obeys pseudo-first ordar kinetics. The apparent rate constant increases with an increase in both the incident light intensity and .the concen­ tration of nitric acid.

The photolysis also occurs with N_ laser or argon ion laser, but the former is much more effective than the latter due to stronger absorption band at 335nm.

The photodissociation yields are measured as.a func­ tion of the incident light intensity, the initial con­ centration of nitrosyl ruthenium nitrate and the concen­ tration of nitric acid and nitrites.The probable mecha­ nism of photodissociation reaction of RuNO(NO,)^ species in nitric acid solution is discussed.

The present results suggest that the photolytic con­ version of nitrosyl ruthenium to Ru(IV) could provide a potential means for improving the decontamination of uranium and plutonium in the reprocessing of spent nuclear fuel because Ru(IV) is unextractable by TBP.

- 83 - Tang Jing-juan.Ye Ming-lu.Mao Yun, Lu Shi-jun,Tang Zhi-hua Fudan University, Shanghai, China. Guo Ze-hong, Beijing Institute of Nuclear Engineering, Beijing, China.

INVESTIGATION OF ADSORPTION PROPERTIES OF THE SILICA GEL IMPREGNATE WITH SILVER NITRATE FOR RADIOIODINE

Increasing attention has been paid Lo the ceseatcU on the removal of radioiodine from nuclear fuel reprocessing off-gases of nuclear power reactor. He have developed a impregnated with silver nitrate for this purpose. In this work, adsorption characteristics and adsorption mechanism of this sorbent for radioiodine were examined.

The adsorption isotherm of iodine obtained shows that the adsorption property of iodine can be described by langmuir equation. According to the dynamic saturation adsorption capacity of iodine and length of Rg-I bond, calculated results indicate that the adsorption of iodine on this sorbent is single molecule layer adsorption and it is a chemical adsorption. The effect of various operating conditions(such as adsorption temperature, superficial velocity, relative humidity, concentration of NOx in feed gas) on decontamination factors and adsorption capa­ cities of elemental iodine and methyl iodide are discu­ ssed. Results show that the sorbent we have developed has good adsorption characteristics for elemental iodine and methyl iodide under the operating conditions, the adsorp­ tion capacity is up to 200 mgl/gSi and the utilization of the silver on sorbent is higher than 9Q%.

- 84 - Wu. M., Yu, H-, Zheng. CF. Fudan University," Shanghai, China

STUDIES ON ISOTOPE SHIFT IN IR SPECTRA AND COMPLEX EFFECTS OF

U02C12- 2TBP

The rate of extraction of uranyl chloride in UO?Clj,-HCl system

by TBP is enhanced under irradiation of C0? laser and isotope effect can be observed. This paper discusses the isotope shift of asymmetric stretching vibrational frequencies in IR spectra of UO_Cl_-2TBP measured by FT-IR spectrophotometer- In order to measure precisely the isotope shift we have studied the effects of the preparation methods of the complexes and calibrated the asymmetry of the peaks. The mean values of the isotope shift obtained from seventeen measurements is 0.88±0.05 cm

The complex effects of the complexes can be attributed to the charge transfer from the ligands to the uranium atom and 7T-bond- p ing energies of U-0 bond in the complexes.' The U-0 bond length and the force constants of U-0 bond have been evaluated using the approximate relation between the asymmetric vibrational frequency 3 and bond length, and the modified Badger's relation respectively. The charge transfer quantity is 0.'»35e, and the 7T-bonding energy

of O-U-0 in U0?C12-2TBP is -132 KCal/mol.

REFERENCES 1. Xu, B-Y-, et al., Ke Xue Tong Bao, to be published 2. Ohwada, K., Appl. Spectrosc., 3ft 3?7 (1980) 3- Glebov, V. A., Koord. Khim., 7 388 (1981)

- 85 - * * ** Hidetake KAK2HANA, Takao OI, Hiroaki WAKABAYASHI and *** Hiroyuki XADOTANI * Sophia University, Chiyodaku, Tokyo 102, Japan ** The University of Tokyo, Tokaimura, Ibaraki 319-11, Japan *** Century Research Center Corp., Chuoku, Tokyo 103, Japan

CHROMATOGRAPHIC CHEMICAL SEPARATIONS OF URANIUM ISOTOPES, AND THEIR FISSION CRITICALITY WITH REGARD TO NUCLEAR PROLIFERATION

A fuel cycle can be evaluated in terms of 1) economical efficiency, 2) independence and 3) nuclear proliferation resistance. For the front end, the U-235 enrichment process is the key process and should sufficiently meet to these three items. Focussing our consideration on the proliferation resistance, a U-235 enrichment process with a large resistance is crucially important since 1) a fuel—grade U-235 manufacturing plant by this process is not easily converted to a weapon-grade U-235 manufacturing plant and 2) costs for inspection activities on a plant by this process are small. In other words, a U-235 enrichment process with a larger proliferation resistance will prevent the horizontal proliferation better with a cheaper cost than processes with a small proliferation resistance. Criticality is the key factor for the proliferation resistance. The resistance of gas diffusion, centrifuge (and laser) processes are, unfortunately, extremely small. There is no criticality problem in these processes even at a very high degree of U-235 enrichment and fuel-grade U-235 manufacturing plants by these processes can be easily converted to weapon-grade U-235 manufacturing plants simply by changing the cascade shape. Chemical enrichment processes of U-235, which the speaker (Kakihana) had initiated some 30 years ago and have been developed in. Japan and in France, may become processes with a large proliferation resistance. Since chemical enrichment systems contain neutron moderators such as H, C and O in abundance, neutrons generated from fission reactions are easily thermalized. Thus, the volume of the system and the degree of u-235 enrichment should be strictly limited not to cross over the criticality. There are three kinds of chemical chromatography processes for U-235 enrichment; 1) complex formation process, 2) redox process between U(IV)-U(VI) and 3) redox process between U(III)-U(IV). The 1st process is still at the stage of fundamental studies, the 2nd now has a pilot plant built by Asahi Chemical Co. in Japan and the 3rd has been developed in France. Although the possibility of industrialization of the chemical processes is still somewhat in question, their technological goal is almost achieved and we believe it is time to discuss the proliferation resistance of the chemical processes. In this presentation, we show some results on criticality calculations of the above 1) and 2) chromatography processes. An important conclusion obtained is that redox process between U(IV)-U(VT) with the HC1 concentration of less than 4 M and complex formation process have a large proliferation resistance.

- 86 - Yang, M., Zheng, Q. K., Wang, Z. L. FYjdan University Shanghai. P. R. C.

INTERACTION BETWEEN PHOTOEXCITED URANYL AND SULPHATE IONS

The luminescence decay of excited uranyl ions in sulphate solution has been investigated with a pulsed nitrogen laser as an excitation source and a transient recorder for lifetime measurements. The uranyl-sulphate complexes are excited by 337 nm laser along with aquo-uranyl ions and all their luminescence can be observed at 514.5 nm. The single exponential decay of the luminescence reveals that the ligand exchange rates of the excited uranyl species are faster than the decay rates and all the excited species reach thermodynamic equilibrium with the ligand species in solution. The luminescence lifetime depends on the concentration of U(VI), sulphate, and the pH of the solution. Similar to the perchloric system, a biexponential decay is observed at sufficient high pK.

The self quenching of *Uol and *UO_(S04)Z gives very good Stern-Volmer plot and the quenching rate constants are 5.1*10 dm mol~ S~ and 1.5»10 dm mol~ S~ , respectively.

A decay mechanism is proposed» Based on the mechanism the expressions of the luminescence lifetime have been derived and .the stability constant of the excited uraoyl- sulphate complex is obtained.

- 67 - Sun, Z.H., Hu, H.Z., Qin, Z.X., Xue, S.J, Institute of Atomic Energy, Beijing, China

THE PRECIPITATION OF Pu(III) OXALATE"

The solubility of Pu(IlI) oxalate in the HN03-H2C2O4 media Is determined in the present work. At different (HNCO, the solubility of Pu(III) oxalate gradually decreases with the increase in the (H-C^O,). Results also show that when the (HNO_) is less tham IN, the increase in the (H-C-0 ) causes a gradual decrease in the solubility of the oxalate, which reaches a minimum and then increases with the addition of more H-C.O,. This is interpreted as the formation of oxalate complexes. At different (H2C«0,), the solubility of Pu(III) oxalate increases with the increase in the" (HNO_) to some extent. The elevation of temperature results in greater solubility of Pu(III) oxalate. The ionic strength is kept at 1-2.3 except when the (HNO.) is 3N, in which case 1-3.3.

Further investigation has been made to study the effects of various variables on the (Pu) in the filtrate, relative filtration time and the characteristics of Pu(III) oxalate crystals. The recommended optimal processing conditions are: (HNCO 1.5M; (H2C_0.) 0.2-O.3M; digestion time 30m.; rate of H_C_0, addition 50%; temperature 30 C. The (Pu(IIl)) may be chosen as needed.

A comparison of precipitation conditions between Pu(III) oxalate and Pu(IV) oxalate shows that Pu(III) oxalate is superior to Pu(IV) oxalate in the ease for filtration and crystalization under experimental conditions.

- 88 - H. CASARCI,G.M. GASPARTNI,ZHANG QUINXUAN*

ENEA FUEL CYCLE DEPT.-C.R.E. CASACCIA-ROME,ITALY

(•JINSTITUTE OF ATOMIC ENERGY,BEIJING.PEOPLE'S REPUBLIC OF CHINA

N,N* DI ALKIL ALIPHATIC AMIDES AS EXTRACTANTS OF ACTINTDES: OUR 'RECENT RESEARCH ON THE POSSIBILITY OF APPLICATION OF THESE COMPOUNDS IN LIQUID-LIQUID EXTRACTION.

N,N' Di alkil aliphatic anidos have been under studies in our laboratory since a longtime,both as an alternative to TBP in Purex-type chemical processes and as suitable extracting agent for particular application in the selective separation of nuclear and non nuclear ions. The main topics treated in this paper are:

1—The role of chemical structure(size,structure and position of aliphatic chain)in determining the extractive behaviour;

2-The state-of-art on the third phase problem(role of che­ mical structure.diluent,Uranium concentration),and methods under studies to solve the problem;

3-Some comparative tests between TBP and a linear amide, carried out in EUREX hot cells by using real dissolution feed stream to determine the decontamination factors for the most important, fission products;

4-A series of runs carried out in mini mixer-settler for the optimization of the flowsheet proposed for the repro­ cessing of high burn-up fuel coming from the Italian TRINO power plant;

£-A proposed flowsheet for the recovery of precious metal, such as gold,by waste stream.

- 89 - 1 + ++ D. Ertel" ", +l£. Heilgeist , A.H. Stollenwerk , M. Weishaupt + Kernforschungszentrum Karlsruhe, Institut fur HeiBe Chemie ++ Wiederaufarbeitungsanlage Karlsruhe, HAK-GmbH

PUREX PROCESS BEHAVIOUR OF HYDRAZOIC ACID

In the Purex Drocess HN3 is formed as an intermediate product of hydrazine oxidation either by nitrous acid or nitrate (in presence of Tc). Hence it will be found in the separation extractors and the downstream staqes of the process.

HH3 is chemically reactive and easily destroyed by oxidation. Physically it is characterized by its low boiling point (37 °C) and fair solubility in TBP. The significance of HN3 for the Purex process is mainly due to its explosion capability, i.e. safety considerations are well to the fore.

During the early sixties when the U(IV)/hydrazine concept came up corresponding safety criteria have been specified, though based partially upon theoretical estimations /l/. In fact, no incidents have been reported since that time which could be attributed to HN3 action. Nevertheless, until now only poor information is available and, therefore, we made it our task to contribute to solving the problem.

At first the development of a suitable and efficient analytical method was necessary. In combination with preseparation procedures azideselective potentiometry proved to be an excellent approach being able to analyze as low as 2 x 10~4 mole HNyiiter /2/. Applying this to process solutions originating from different R+D installations at the Institute of Hot Chemistry as well as to samples taken from the WAK production plant systematic studies were made which gave an interesting insight into the behaviour and distribution of HN3 in the Purex process. By combination of the measured typical HN3 concentrations of various process streams with flowsheet data production rates could be derived which will be presented and discussed in detail. Besides the fact that realistic HN3 contents of Purex solutions are always well below given safety margins it could be demonstrated that in the conventional Purex process involving external U(IV) production distinctly more hydrazoic acid is formed than in the advanced procedure characterized by the electrolytic in-situ reduction technique 13/.

Ill C.S. Schlea et al., USAEC-Report DP-808 (1963) 12.1 D. Ertel, Atomkernenergie/Kerntechm'k 42 (1985)87 131 F. Baumga'rtner, H. Schmieden Radiochim. Acta .25 (1978)191 - 90 - Puan Y.F.. Zhang X.Y., Zhon Z.H., Hu J.X., Liu S.Y. Institute of Atomic Energy, Beijing, China

PHOTOCHEMICAL REACTION IN THE AQUEOUS SOLUTION Put III) 2+ Fe -N2Hg-HN03

The photochemical reaction in the system of Pu(IIl)-

Fe -N_H5-HN03 was studied to explore its possible appli­ cation in spent fuel reprocessing. A GGH-120 Hg lamp was used as the light source. The effects of various factors on the photoreaction were investigated.

Experimental results showed that Fe +, N,H* and Pu(III) were oxidized rapidly and completely during the course of irradiation. The initial rate of photooxidation of H s Fe and N2 c * proportional to the power of light,

[Fe ] and [N-H*] respectively. In the pure HN03 solution, HNO„ and 0„ were produced during the irradi- 7 . + . ation, while in the system containing N_H,. with or without Fe 2+ , HNO~ wasn't detected until the complete 2+ + oxidation of Fe and N_H,_ . Experimental results sug­ gest that photooxidation of Pu(lII) occurs via the following three stages: I) slow oxidation of PulIII) to Pu(IV). The initial rate of photooxidation is dire­ ctly proportional to [Pu], [H ] and [NOT], but decre­ ases with the increase of [U]. II) rapid oxidation of Pu(lll) to Pu(IV). Ill) disproportionation of the formed Pu(IV) to Pu(III) and Pu(VI). Irradiation accel­ erates the rate of disproportionation of Pu(IV) and shifts the equilibrium to the right. It was observed that the equilibrium quotient of the studied photore­ action increased with the increase of HNO, concentra­ tion. The yield of Pu(Vl) was considerably reduced when Fe3+ was present in the system. « - 91 - A.M. Koulkes-Pujo, J.F. Le Marechal, A. Donnond, G. Folcher U.A. CNRS-CEA 331, Centre d'Etudes Nucleaires de Saclay 91191 Gif sur Yvetfce Cedex (France)

METHYL FORMATION OF REDUCED BISCHL0ROBIS-(PENT/fcYCLOPENTADIENYL) THORIUM(IV) AND URANIUM(IV), BY FULSE RADIOLYSIS OF THEIR SOLUTIONS IN TETRAHYDRO- FURAN.

The existence of thorium(III) oxidation state being still controversed, wc tried to show if it vas possible to obtain it by reduction with solvated electrons created by pulse radiolysis of tetrahydrofuran. The experiments were carried out using bischlorobis«(pe>ntamethylcyclo- pentadienyl) thorium, (C Me )_ ThCl,, in tetranydrofuran solutions. To check the validity of our results, similar experiments were performed with the U(IV) homolog compound, known to have already been reduced by electrochemistry. As for the pulse technique, a Febetron 707 accelerator was used. It delivered pulses of 15 ns base duration of approximately 1.8 Mev electrons with doses from 50 to 90 Krad. Tran­ sient species were detected by means of their absorption spectra. With (C,.Me_) ThCl a well structured spectrum was immediately obtained after the pulse, presenting four peaks at 470, 525, 600 and 650 nm. • rst The decrease of these absorptions is 1 order and has the same rate constant at each wavelength (1±0.07x10 s ). It led after 160 us to a different spectrum. As for (C_Me_)-UCl_, only an absorption immediate­ ly appeared at 700 nm, giving 800 ms after the pulse, two peaks at rst —1 660 and 750 nm by a 1 order reaction and a rate constant of 11.k s . The results obtained supported the existence of reduced Th(lII) and U(lII) obtained by means of solvated electrons as the reducing species. Assignement of these optical spectrum transition6will be discussed.

- 92 - FAN XIANHUA et al. Institute of Atomic Energy, MNI ZHAO XIRNGLIN et al. Beijing Institute of Nuclear Engineering, MNI

A STUDY ON THE BEHAVIOUR AND RESTRAINT OF Ru IN POT VITRIFICATION PROCESS

Behaviour and restraint of Ru in pot vitrification have been studied- Simulating experiments were performed using Ru-103 as a tracer in a stainless steel apparatus with an off-gas tube which is 4 mm in diameter and 0.1 mm in thickness.

The results obtained under given conditions show that the percentage volatilization of Ru is about 30-60%, which depends on several factors, such as rate of tem­ perature rise, geometric shape of off-gas tube, vapor pressure of the off-gas system and feed composition. The Ru volatilization is found to be significantly af­ fected by nitrates which have the decomposition tempe­ rature approaching to that of RuNO(NO,)'yH_0. The main form of Ru volatilized during vitrification process is RuO.. X-ray diffraction data show that the black deposit on the off-gas tube is RuO_.

Denitration of feed with HCOOH can reduce the volati­ lization to about 20%. It is also found that by adding reducing agents such as iron powder, or silicon powder to denitrated liquid, Ru can be partly restrained in pot. Ru loss from pot can be reduced to less than 17%.

- 93 - Lin, C.S., Huang, M.X. Institute of Atomic Energy, Beijing, China

INFLUENCE OF MOLYBDENUM ON THE SOLVENT EXTRACTION OF NIOBIUM FROM NITRIC ACID

Investigation was made in the influence of macro molybdenum on the extraction of raicro niobium by different solvents from an aqueous phase which contains nitric acid, nitrate and molybdenum in various concentrations. Niobium-95 and molybdenum-99 tracers were used for the determination of distribution coefficients of niobium and molybdenum. Results indicated that there was an obvious influence of molybdenum on the extraction of niobium from 0.4-1.0M HNO., by TBP, HDBP and Aliquat-7402. The'distribution coefficient of niobium increased by A to 250 times with the addition of inactive molybdenum into the extraction system.

Based on the experimental data, the following equations are suggested for extraction equilibrium of niobium and noiybdennira: , lNb(OH)<5-x'-y){N03V+X+MOOI

NO MoO. A MoO. +x' Nb(OH) (5_x)+yH +yNO~~ [Nb(OH) (5_x._y) (N03) (y_2) (Ho04> ]+2N034yH20 H2° MoO. N03 4 n. n=x'+y-2y»S0 (Nb(OH). ,_ .(Mo04> ] +(y-2)N03

The results of slope analysis show that the extracted niobinm species by HDBP is a mixture in the following form:

[2Nb(OH)(N03)3H2(DBP)3 +Nb(OH)(N03>2H2(DBP)^].

- 94 - T, ADACHI^ T. MUROMURA, H. TAKEISHI and T. YAMANOTO Japan Atomic Energy Research Institute. Tokai-mura, Ibaraki, 319-11, Japan CHEMICAL PROPERTIES OF SIMULATED SPENT FUEL DISSOLUTION BEHAVIOR

In order to elucidate the chemical behaviors of fission products in spent nuclear fuels, several kinds of simulated spent fuels were prepared and their dissolution behaviors in 3M nitric acid were investigated. Simulated spent fuels corresponding to burnup 5% to 30% FIMA were prepared by adding non-radioactive FP elements to uranium in nitrate solution, evaporating to dryness and heating at 1000 to 2000"C under 4% H2 + 96% He. The resultant pellets were dissolved in 3M nitric acid. Insoluble residues formed were filtered off and dissolved by sealed tube method. FP elements in filtrate and insoluble residue were determined by ICP-AES and AAS. When UO2 pellets corresponding to 5% burnup were dissolved in 3M nitric acid at 90°C, the relation between amounts of insoluble residue and treated temperature was as follows. Amounts of insoluble residue kept constant(ca. 0.3wt%) up to 1600*C. More than 1600*0, however, they decreased to about 0.15wt%. By the chemical analyses , following results concerning the distribution of elements were obtained. i) The main components of residue were Mo, Ru and Pd. ii) U, Ce,Nd(and lanthanides), Zr, Ba and Sr were existed in filtrate. The relation between mole ratio of Mo, Ru and Pd in insoluble residue and treated temperature showed that mole ratio kept constant up to 1600"C and more than that temperature Mo mole ratio increased whereas Pd mole ratio decreased. These results showed that insoluble residue formed in higher treated temperature consisted of Mo rich alloy. Other experimental results obtained at different burnup and oxygen pressure will also be presented.

- 95 - L. Stieglitz, R. Becker, H. Bautz Institute for Hot Chemistry Nuclear Research Center Karlsruhe, FRG

THE ROLE OF PLUTONIUM IN THE DEGRADATION OF TRIBUTYLPHOSPHATE IN THE PUREX PROCESS

In the Purex process, degradation products of- the solvent have a great influence on process performance, on the quality of the products urarmim/plutotuuvn. and on losses of heavy metals to the waste. In the study of solvent degradation both chemical and radiolytic reactions have to be considered. Here the role of Plutonium is of special interest. On the one hand, being an emitter it acts as an internal radiation source, while on the other .hand it shows a strong catalytic effect on the hydrolysis due to its ability to form complexes with alkylphosphorous compounds. Laboratory experiments were performed with the objective of clearly defining the radiolytic and hydrolytic contribution of plutonium to the formation of HDBP. The experiments were carried out in mixed phases of 30 volX TBP n- Alkane and 3 M HNO3 w^h a phase ratio of organic/aqueous = 3:1 at temperatures of 25°, 50° and 75° C. The concentration „range of Plutonium in the organic phase was 16-18 g/1. An evaluation of the data gives the following results: The radiolytic influence of plutonium is described by a HDBP* formation rate of 30 mg/Wh (G- value = 0.38), HpMBP** and H3PO4*** formation is neglegible. These data are in agreement with previous experiments. Superimposed to the radiolytic degradation, the hydrolysis proceeds as a first order reaction with respect to the TBP concentration. The hydrolysis constants k /hr~V are 7.8-10"6 at 25c C, 8.3-10-5 at 50° C and 9.1-10-4 at 75° C. The temperature dependance fits the Arrhenius equation with an activation energy of 78.95 kj/mol. In comparison with pure H+ catalysis, the presence of plutonium enhances the hydrolysis rate by a factor of 8 to 10. These data are compared with the influence of other tetra-and hexavalent metals: Similar enhancements of TBP-hydrolysis are found with U(IV) and Zr(lV), whereas U(VI) up to concentrations of 33.4 g/1 (organic) shows only a minor effect. The activation energies for the temperature range studied are independent on the nature of the heavy metal and amount to 79 kj/mol ( +_ 555). With these improved data, HDBP formation* rates in the various cycles of the Purex process can be estimated and the influence on "process performance be predicted.

* dibutylphosphoric acid (HDBP) ** monobutylphosphoric acid (H2MBP) *** phosphoric acid (H3PO4)

- 96 - Feng,X.Z. Institute of High £nprgy Physics,Arademia Sinjca Beijing, China

BALANCE BE1VJEEN COORDINATION BOND AND VAN DFR WAAI S ENERGIES iff nit COMPLEX CIWOUNDS or ACTINIDES (l)

In the analysis oT the crystal structure nf" about 280 complex compounds of Actinides and lanthanides which all agree with the saturate packing rule arid the unirorm packing rule of Mie Packing Model,we found four compounds of" special interest. They are:

(K2(U02)2(C2t)/j)3iH2rj|n(I), [(NH4)2(U02)2(C204)!3n(II),

(NHA)^U02(C2Dfl)3 (III),and [(NH^UO^C^)^ IV). (I) and (111) each has 6 U-0 honds with oxalate ions,whereas (II) and (IV) each tins only 5. The sum of the interligand van der Waals energies between tliese bonded oxygen atoms of (I), (II),(III),and (IV) are -1. 33t,-2.6Bf ,-1.26t,nnri -2.5->€ respectively,where< is the maximum van der Waals attractive engergy between two oxygen atoms. lhus,the U-U coordination bond(with oxalate ion) energy is equal to 1.310.26 and is close to be €.Therefore,the balance between van der Waals and coordination bond energies can be considered as the foundation of the Packing Model for the weak bond compounds.

- 97 - Xu,-V»Ii>Li,X;F. ,Feng,X.Z. Institute of High Energy Physics,P.O.Sox 2J32,Beijatrag,thivraa Sun,P.N. The University or Science and Technology of China

UNIFORM PACKING AND ITS PREDICTION ON MOLECULAR STRUCTURE OF LANTHANIDES AND ACTINIDES

For organometaliic and coordination compounds of f-group elements with weak bonds,the present paper suggests a scheme to approximately describe the uniform packing of ligands surrounding the central metal ion. The uniform packing was confirmed by a detail statistical analysis of the experimental data of such compounds.The atoms of coordinated ligands were approximately considered as van der Waals balls.The solid angle subtended by ligand i divided by 4TTwas defined as the vector SAF.. The uniform packing was approximately described as

^.SAFd = 0 (1) and i^gpf- = mi" (2) ;i.e. sum of vectors SAF. equals to zero,and sum of squares of gap angle' gp. . between cones i and j subtended by all neighboring ligands i and j takes minimum value. With this scheme we wrote a cornputer program CONPACKS to calculate the strucfcuresfbond angles) of several compounds with coordination number from 4 to 7, and a reasonably good agreement with the experimental data was achieved.

- 98 - Guo Ao-ling,feng Xi-zhang,Liu Li,Xu Ving-ting,Li Xing-fu Application department,The Institute or High Energy Physics, Sun Penq-nian Biology Department,The University of Science and Technology of China

"SATURATE,UNIFORM,AND INTERLOCKING" IN LIGAND PACKING STRUCTURAL CHARACTERS OF ACTIMDE COORDINATION AND ORGANOMEfALLfC COMPOUNDS

Quantitative treatment of ligand packing has been carried out for more than 150 structures oF actinide coordination compounds. The mathematical method is similar to the cone packing model approach

1-The Regions of packing saturation exists with average SAS(The Sum of Solid Angle Factors) value 0.81 for actinides (IV) and 0.90 for uranyl structures. Standard deviations are 0.05, thus demonstrating an equilibrium between bonding and steric efFects. 2.The vector sums of the SAr(Solid Angle Factors) of coordinating ligand,i.e. 3.SAFT of all structures approach to zero. 3.The closest non-bonding distances between the atoms from neighbouring ligands are in the range of the sump of van der Waal© radii of the corresponding atoms.These facts simply mean that the ligands are contacting and interlocking with each other.

The above-mentioned characters,which are typical in ionic lattice, provide clear evidence that molecular structures of actinide coord­ ination compounds are essentially determined by geometrical factors.

I.Feng Xi-zhang et al.manuscipt to Polyhedron 2.Li Xing-fu,Ph.D. thesis,The University oT Marchester (1982) 3.R.D.Fischer and Li Xing-fu,J.less Comm.Metals112 (1985) 303

- 99 - Wang, W.Q., Ding, Y.W., Yi, M. Department of Technical Physics, Peking University Beijing, China

SYNERGISTIC EXTRACTION OF URANYL PERCHLORATE BY THE TERNARY

SYSTEM OF AAC SPECIES COMPOSED OF TTA-PMBP-(C6H5)^AsCl

A new ternary synergistic extracting system composed of two chelate extracting ligands and one ion association ligand, namely AAC species, has been studied. In previous studies, uranyl perchlorate was extracted by the binary system of thenoyltrifluoroacetone (TTA) or l-phenyl-3-methyl-4-benzoyl- pyrazolone-5 (PMBP) with tetraphenylarsonium chloride ^l^^AsCl in chloroform solution.

The binary synergistic equilibrium constants were determined to be logPA c=3.97 (TTA+(C6H5)^AsCl system) and log(3A c = A.86 (PMBP + (CgH5)^AsCl system) respectively. In the present work, the mechanism for the ternary synergistic extraction of uranium (VI) is investigated. It is found that synergic effect occurs during the extraction of uranyl perchlorate with the chloroform solution of TTA + PMBP + (C6H5)^AsCl and the principle of minimum density of electric charge plays an important role in this system. The formation of a ternary extracted complex (CsHs^AslK^ClO^,) (TTA)(PMBP) is confirmed by the slope method and the perchlorate is determined by the methelene blue spectro­ photometry method. The equilibrium constant is calculated to be logpA][A2C = 5.52.

- 100 - long -Tihong, Tai Deronq, Liu Jun and Yang lichun Institute of Nuclear Energy Technology Tsinghua University P.O.Box 1D21, Beijing, China

THE DEPENDENCE UP URANIUM (VT.) ElEnTRO-REDUCI KIN RATES ON COMPONENT HMTNT RATIONS

As a fundamental research for the development of the in-situ (jranium and plutonium electro-reduction process and equipment, Hie dependence nf l)(VI) elertrn-reductinn rales on component concentrations has been investigated with the system UOjtNO^j-

IINn|-N2ll5N03(ll2O)/3O?n TBP(OK). The electrolytic cell employed is a glass column with an internal diameter of 50 mm. The sieve plates are made of titanium, serving as cathode, the anodical central rod is made of platinum or stainless steel, the polyethylene material is used for the insulators between anode and cathode. The oscillation of reciprocating plate makes both phases dispersed.•The U(IV) formation rates were measured under varying component concentrations.

Ihe results show that the presence of hydrazine as the supporting redurtant or stabilizer is necessary for the reduction of tl(VI). In the range of experimental concentrations, the U(Vl) reduction rates are mainly dependent on the U(VI) concentration in the system and slightly dependent on the IINtk- and N II concentrations. Ihe data for the present system are well correlated by the following rate equation:

dUfVIl r ,0'7«87 0,06X3 , ,0.0173 = k U(Vl) ~ dt f J [N2HS] [UNO,] here the rate constant k is a function nf temperature, k=0.0019 at t=25°C.

- 101 - Zhu Yongjin, Meng Zugui, Xu Jinming, Liang Junfu, Zhuang Yongneng, Zhang Wei, Song Chonqli (Institute of Nuclear Energy Technology, Isinghua Univ.) Kang Wencheng, iHiiang Yaofang, Sun Suoiiang Ouan ikiirain (Shanghai Yue Long Chemical plant)

THE REMOVAL OF RADIOACTIVITY FROM LANTHANUM OXIDE

Most radioactive nuclides of three natural radioactive series exist

in Laa03 produced from monazite. Radiochemical separation-ct - spectrometry,J-spectrometry and solvent extraction-liquid scintillatior 2 5 7* measurement indicate that Ac and it's daughters are the nuclides of great importance and the separation of from ta203 is the key problem for removing radioactivity from La,03.

It has been proven that acidic organophoshphorus extractants are most 1+ H effeetive forTthe separation of" Ac from La

The halF pti values, at which 50% metal is extracted, of 30S (V/V) HDEHP-Kerosene are 0.47 for La*+, 0.76 Tor Ac3*, and that nf 30K 3+ 3 + HEHEHP-Kerosene are 1.31 for La , 1.51 Tor Ac , respectively.

The regression equations for the distribution ratio of Ac'-'' and La3 + and for their separation "factor and *he procBss para.~et&te"=. Kiirvi-were tested in mini-centrifugal extractors are given. The whole process was verified in an industrial scale experiment by using multistage mixer-settlers. The total a-radioactivity in La203 decreases from

1500 cph in raw La203 to less than 1 cph in the product (in 1 inch dish). The recovery of LajO 3 is greater than 95SJ.

- 102 - Wang, S.U., Zeng, Y.K., Yi, P. The 230 Institute, Changsha, Hunan, China

AMIDOXIME-POLYACRYLONITRILE ION-EXCHANGE FIBER AND IT'S ADSORPTION BEHAVIOR FOR URANIUM

The amidoxime-polyacrylonitrile ion-exchange fiber is made by the reaction of hydroxylamine with commercial polyacrylonitrile fiber. With a total adsorption capacities of 2.7meq/g, it can be used for the concen­ tration and separation of uranium from dilute solutions. The IR-spectra of AO-PAN fiber exhibits characteristic absorption of^amidoxlme, i.e. amine stretching absorp­ tion at 3400cm OH stretching at 3320cm, CN stretching of the hydroxyimino group at 1650cm, and NO stretching of hydroxyimino group at 930cm. The adsorption of uranium from dilute solutions can reach 1.25mg/"g. The adsorption of uranium in a fiber column has been studied and applied to the determination of uranium in ores and rocks with satisfactory results.

- 103 - Choppin,G.R., Dept. of Chem. FSU, Tallahassee, FL 32306 LIU, Q.L., Dept. of Appl. Chem. USTC, Hefei, Anhui, China Sullivan, J.C., Argonne National Lab., Argonne, IL 64309

'mERMOuWAMlC. STUDIES OF CURIUM CONPLEXATION

Curium has become available with relatively low specific activity (3x10' alpha decays m~*. mg-1) with high content, 96.9Z, of 248Cm (ti/2 = 3.4xl05 y). With this material direct calorimetric measurements can be made using mg quantities in the mini-calorimeter(1) of FUS's Lab.. The systems Cm+Ac and Cm+EDTA were chosen for study as these ligands form relatively weak and very strong complexes respectively. The AH results of the calorimetric titrations with EDTA corresponded to the reaction: M4"3 + (H2EDTA)_2= (MEDTA)-1+ 2H+ and these ought to convert to the direct reaction M+3 + (EDTA)"4= (MEDTA)-1, by the deprotonation enthalpy. The following table lists the calculated enthalpy values of the curium titration for the reaction of M+L to give ML (L=Ac~ or EDTA) and other thermodynamic parameters of Cm(III) complexation. ligands AHCKJ.mol-1) AG(KJ.mol-1) &s(J.mol"1.K"1)

Acetate* 5.95 0.4 -11.68 0.13<2> 57 2 EDTA** -29.3 1.3 -96.2 0.5(3) 225 6

* 1=2.OM NaClOj, ** 1=0.5M NaClO^ (1) Ensor, D.D., Kullberg, L. and Choppin, G.R., Anal. Chem. 49(1977)1878 (2) Choppin, G.R. and Schneider, J.K., J. Inorg. Ncul. Chem. 32(1970)3283 (3) Ensor, D.D. Progress Rept. DOE/ER/10489-09, Tech. U., 1982

- 104 - Xin, W.D., Chen, L.Q-, Dong, C.F. Department of Modern Physics, Lanzhou University Lanzhou, Gansu, China

INVESTIGATION ON SYNERGISTIC EXTRACTION OF URANIUM WITH D2EHPA-TRP0- TBP MIXEQ EXTRACTANT FROM SULPHURIC ACIO SOLUTION

This paper describes the synergistic extraction of U(VI) with the ternary mixed extractant of D2EHPA-TRPO-TBP in Kerosene from sulphuric acid solution. It shows that, while the synergistic or the antagonistic effect is mainly determined by the extraction conditions, such as the degree of saturation of uranium in organic phase(SD), TBP and TRPO both evidently lead to the synergistic effect when SD >ss than 60% but antagonistic effect occurs while SD is greater tha. ,i. Other factors of importance are the nature of neutral organophosphorus compound and the mole ratio of neutral organophosphorus compound to D2EHPA(R). For TBP with weak affinity, there is no synergistic effect at various values of R(TBP/D2EHPA) while SD is greater than 60%. But for TRPO with strong affinity, synergistic or antagonistic effect appears as the ratio R(TRP0/D2EHPA) changes. When R(TRP0/D2EHPA) is greater than J, the effect is synergistic. Once R(TRP0/D2EHPA) becomes less than j, the effect is antagonistic and the minimum of DT appears at R(TRP0/D2EHPA)=l/5.

Also, the total distribution ratio of U(VI) Dy is nearly equal to or less than the sum of Di, Q\z and DJJ under experimental conditions. Therefore, it con be concluded that no advantage will be gained by the use of ternary extractants for the extraction of U(vT) from sulphuric acid aolution.

*

- 105 - Zhao Aimin, Tao Zuyi, Tong Wengong, Chen Xingqu Department of Modern Physics. Lanzhou University Lanzhou, Gansu, China

STUDIES ON ION EXCHANGE EQUILIBRIA AND KINETICS: Uo|+—H+ CATION EXCHANGE KINETICS

The kinetics of cation exchange 2RH + U0|+=rf: I^UOj + 2H+ for forward and reverse reaction with 001x7 strong acidic resin has been studied. It is found experimently that, at low concentration, the forward exchange rate is controlled by film diffusion and at high concentration by particle diffusion; on the contrary, the reverse exchange rate is controlled by particle diffusion at all concentrations. The difference in mechanism for forward and reverse reaction is attributed to the high preference for UO?+ over H+. The integral particle inter-diffusion coefficients for forward and reverse exchange and the ratios of film inter-diffusion coefficient to liquid film thickness for forward exchange have been calculated.

- 10« - Huang Haoxin, Hou Shubin, Liu Lanzhen, Zhu Guohui Institute of Atomic Energy, Beijing, China

THE EXTRACTION BEHAVIOR OF RuNO COMPLEXES-WITH f-IRRADIATED TBP-KEROSENE

Th«» retention of Ru in the recycled organic extractant is serious. In this work, some experiments were carried out to elucidate the possible reasons for this serious retention.

1. The retention of RuNO complexes in irradiated solvent was small for 3036 TBP-kerosene, TBP and kerosene which were not pre-equilibrated with HNO-, before irradiation.

If they were pre-equilibrated with 1M HN03,the retention in kerosene or TBP was small too. The retention in 30% TBP-kerosene increased with the dosage of irradiation.

2. The retention of ruthenium in irradiated TBP-keroserie increased with the concentration of pre-equilibrating nitric acid and the ageing time after ruthenium extrac­ tion. After washing with 2M HN03 and 0.5M sodium carbo­ nate at 30 C, the retention was quite large.

3. After irradiation, the solvent was separated into Na„CO, extract, H_0 extract and neutral phase by Becker's Method. The retention of ruthenium in H„0 extract was smaller. Its component is mainly long chain acidic 95 phosphate esters. They can extract Zr strongly, but they extract and retain only a little ruthenium. However, the retention of Ru in neutral phase was large. The retention mechanism will be studied later.

- 107 - Zhang Qingxuan, Zhang Jiajiun, Jiang Dongliang, Tian Baoshang, Li Zhaoyi, He Jianyu Institute of Atomic Energy, Beijing, China

THE INVESTIGATION ON NEPTUNIUM BEHAVIOR IN ELECTROLYTIC PARTITIONING PROCESS OF URANIUM AND PLUTONIUM

The electrolytic oxidation-reduction of Np(V,VI) in HNO3 solution was studied. Experimental results showed that the electrode process of Np(V)-Np(VI) couple is reversible, half reaction time of the process mentioned above is about 1.5 minutes under given conditions. The overpotential of reduction of Np(V) is high, which makes it difficult to reduce Np(V) into Np(VI) directly at cathode. Owing to a large quantity of U(VI) produced through electrolysis, it is presaged that neptunium will be mainly in tetravalent state in the electrolytic M-S battery.

A new type of electrolytic M-S battery was developed, in which anodes were installed in each settling chamber without any specific anode chamber in the battery. Owing to using of the mechanical stirrer driven by a wheel gear, stage efficiency is high. Demonstration campaign was carried out. It follows from the results that the yield of Pu is 99.90-99.99%. Separation factor of U from Pu is 3900-33000. Material balance of U and Pu is satisfactory. Heavy accoumulation of Np in the battery was observed. Np in the battery is mainly in the tetravalent state. It is believed that it is difficult to recover Np quantitatively from single fluent (e.g. IBP or 1BU) under normal conditions of partitioning step of the PUREX process.

- 108 - Yu. E.J., Liu, L.H., Huang, H.A. Institute of Atomic Energy, Beijing, China

AN INVESTIGATION OF THE FORMATION OF A THIRD PHASE IN THE EXTRACTION OF PLUTONIUM(IV) NITRATE WITH TRIBUTYL PHOSPHATE

The appearance of a third phase in the extraction of Plutonium(IV) with tributyl phosphate must be eliminated as it disturbs the operation of the extraction process and probably causes a criticality accident. Only limited information in this field has been published in litera­ ture.

In this work, S , the maximum concentration of Pu(IV) in 30% TBP without formation of the third phase, was measured as a function of the nitric acid concentration in the equilibrated aqueous phases, €„', temperature and nature of diluents.

Results show that the minima on the S vs. CH curves in 0.5 to 2 M nitric acid were observed at 17 C and 26°C. The maxima on the S„, vs. C„ curves in 6 to 7 M FU H nitric acid occurred at 17°C, 26°C and 35°C. It is found that the molecular size of n-alkane diluent influences Sp significantly. The effects of kerosene and n-dodecane on S_ were tested. Pu The concentration of plutonium(IV) in the third phase increases with the increase of the plutonium(IV) concentration in the equilibrated aqueous phase. Sp is enhanced by the addition of lauryl alcohol.

- 109 - P.M. Levins, B.W. Seatonberry, K.D. Reeve, R.K. Ryan, W.R. Ellis, S.A. Dowswell and S.A. Tophani.

Australian Atomic Energy Commission, Lucas Heights Research Laboratories. Private Mailbag, Sutherland, N.S-liJ. 2232, Australia.

LEACHING OF ACTINTDES AND TECHNETIUM FROM SYNROC

One of the most important properties of a nuclear waste form is its ability to Tetain the acttnldes and long-lLved CLsslon products. In order to evaluate SYNROC -as a host for the actinides and Tc, the AAEC has built'a small-scale production line consisting of four interconnected glove-boxes. SYNROC is being fabricated containing up to 0.03Z 2l,1Wm, 0.5Z 239Pu, 1.3Z 23?Np, 0.004% ""cm and 0.57. 99Tc.

SYNROC is prepared in 75 g batches by adding 10 wt7. (oxide basis) PW-4b simulated waste, doped with Tc or the actinide of interest, to a slurry containing the SYNROC precursor. The slurry is .flash-dried, ground using a hammer mill and calcined -in a rotary furnace for 90 minutes at 750°C tinder an atmosphere of 3.57. H2/Nz. The calcined powder is then blended with 2X Ti metal powder and hot-pressed for 2 hours at 1200*C and 15 MPa pressure in a graphite die.

Disc specimens cut from SYNROC pressings are leached at 70°C or 90°C Under static (MCC-1) test conditions. Leachants are analysed for* 99Tc by liquid scintillation counting and for the actinides.by. "electroplating followed by ct-spectrometry. The normalised $.,:••• differential leach rate for 99Tc at 90°C is 0.09 g m~2 day-1 initially, and falls by a factor of one thousand in the first 300 days. This rapid decrease in leach rate with time has also been observed for readily soluble elements such as Cs and Sr.

SYNROC specimens containing 233Pu and <*1Am have been leach tested under MCC-l test- conditions at 70BC. The normalised leach rates averaged over the first 7 days have ranged from 0.6-1.6 x 10 g m day-1 for 239Pu and 1.5-6.7 x 10~5 g m~2 day-1 for 2,,1Am. These leach rates are based on solution analysis. Acid washing of the leaching vessels has shown significant quantities of the actinides on the walls of the vessel. Examination of the surfaces by the a-track etch technique has revealed star-like clusturs of ot-tracks corresponding to particles up to I Dm diameter. Polishing of the flat surfaces of the SYNROC specimens prior to leaching reduces the activity on the walls by a factor of 5, suggesting that minute particles of SYNROC have been lost from the rough, unpolished surfaces.

The very low.leach rates measured for Tc and the .actinides indicate that SYNROC Is an ideal host for these elements.

The authors gratefully acknowledge the support for this work by the Australian Government under the National Energy Research, Development nd Demonstration Program. /

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U(I V I O •0 pec - 3 ca itr o 3 »1 er ^~» o o <4 a. CD O 3 H CO O ct N_^ 1 3* 1 CO Ge, Q.R., Rang, S.F., Zhou, M. Department of Chemical Engineering, Tianjin University Tianjin, China

STUDY ON THE KINETICS OF AUC THERMAL DECOMPOSITION BY NON-ISOTHERMAL METHOD

AUC (A.mmoniutn Uranyl Carbonate) conversion processes have been adopted extensively in nuclear fuel cycle. Investigation of the kinetics of these processes, however, has not yet been reported in detail in pub­ lished literature.

In the present work, the decomposition kinetics of AUC in nitrogen has been determined by non-isothermal method. DSC curves are solved with computer by Q.R.Ge*a method. The results show that the particle size has no apparent influence on decomposition rate,and the kine­ tics obeys Avrami-Erofeev equation within 9094 conver­ sion. The apparent activation energy and preexponent are found to be 25.2 Kcal/mol and 2.17 x 10 /sec respectively.

The structure change during the decomposition and reduction of AUC in hydrogen has been investigated. It is indicated that the specific area increases sharply while AUC is decomposed into UO, , whereas decreases during the reduction of UO, to U02 . A SEM microgragh shows that the particle of U02 via AUC is characterized by having a "Card house" structure.

- 112 - Wu, X., Wang, Y.L., Chen , W.J., Zhu, L. Sichuan University Chengdu, China

ADSORPTION BEHAVIOR AND ISOTOPIC EFFECT OF URANIUM ON DB18C6-FORMALDEHYDE CONDENSATION POLYMER

Adsorption behavior and isotope effect of U(III). U(IV) and U(VI) on DB18C6-formaldehyde condensation polymer from chloride solutions were investigated. U(III) was prepared by mercury cathode electrolysis from 7N LiCl- 1NHC1 solution. The presence of high concentration of LiCl improved the stability of U(III) against oxidation remarkably. As a result, operations were made easier. Distribution factor K" and distribution ratio Kd of U(III), U(IV) and U(VI) on a chromatography column of the polymer with serial eluants of LiCl-HCl solution were reported. Elution curves and isotope distribution curves .were obtained for U(III). U(IV), U(III)-U(IV) and U(IV)-U(VI) systems. Enrichment factors of U-235 for some systems studied are summarized in the follo­ wing table. system eluant column length E.F. U(III) 8NLiCl-lNHCl 4 7cm 1.0022 U(III)-U(IV) 8NLiCl-lNHCl 4 7cm 1.0045 U(IV) 5NLiCl-lNHCl 100cm 1.0045

U(IV)-U(VI) |-3NLiCl-lNHCl 30cm 1.0043 0.5NHC1 U(III), 201x7* 7NLiCl-lNHCl 4 7cm 1.011

* anion exchange resin

- 113 - T. Ggrgenyi an E. Wehner, NUKEM GnfcH, Roderibacher Chausse 6, D-6450 Hanau/11 FRG

HCDUCTICH AMD CEAR&2EERIZftXICH GF KTR^FUEL ElflEHTS WT1H I£W HJ- RICHH) T2RMHUM USING URANIUM5IIJCIEE FUEL

By the development of fuel elements for Material Test and Research (MTR) leactors with low enriched Uranium (<20% U-235) the highly dense UoSi-j ^uel ^"J-1- replace UA1 , which is the stadard MTR-fuel with highly enriched uranium. Thexcase or tubular shaped MTR-fuel elements contain several fuel plates incorporating the fissile ma­ terial. MTR fuel elements with uraniumsilicide fuel are fabricated similar to fuel elements with UA1 using the picture frame technique. Ura­ nium metal and silicon ar§ canelted to a button, which is crushed to powder. This fuel powder is mixed with powder and inserted into a frame of aluminium alloy and cladded with two aluminium alloy sheets. This package is rolled down in several steps yielding the fuel plate with the specified geometry. Fuel plates and structural parts of aluminium are assembled to the fuel element. 1982 the worldwide first U_Si„ full size fuel elements with high uranium density were fabricated by NUKEM and irradiated in the Oak Ridge Research (ORR) reactor. Fuel elements with UoSi2 are pro­ S 6- duced today in routine scale. The majority of the U_3 i2 fuele! merit production at present is carried out by NUKEMT Futher develop­ ment are made in our place to increase the fuel density (high flux reactors) e.g. by using U_Si. The characteristics of silicide fuels is discussed with regard to the U-Si phase diagram. The quality control of fuels, fuel core, fuel plates, and fuel ele­ ments, including all structural parts, is carried out according to the most up-to-date methods. Very accurate U assay is required for the U-Si- powder (0,05- 0,10% rel.) to fulfil the specification anil "safeguard" require­ ments. To check the "accuracy" and "reproducibility" of the method, "synthetic samples" are analysed parallel to the routine samples. The isotopic ratio of U is measured by mass-spectrometry. For the determination of impurities in th?. raw materials and in U^Si. powder different analytical methods (e.g. AAS-, emission spectrographic-, electrochemical techniques) are applied. The composition of uraniumsilicide is measured by X-ray ponder dif- fractrometry or by semi automatic image analysis on the polished and etched metallic .surface. The fuel plates are analysed by a nondestructive (185 KeV jf"-ray of U-235) technique. For the -alibration samples of low, middle and high U concentration regions are selected and analysed by the des­ tructive technique.

n-i - Zhou.M.L., Jin,J.N., Zhang, S.Y., Xu, D.O., Oin, S.S. Institute of Nuclear Science & Technical of Sichuan University Chengdu, Sichuan, Chian

THE PRODUCTION OF 211At AND ITS COHPLEXATION WITH CROWN ETHERS

2HAt was produced by irradiating Bi target with 21 Mev «tf beam Via 209Bi(of, 2n)211At reaction at a 1.2M cyclotron made in China. The isolation of 2^*At was effected by dry distillation. The quality of product was evaluated with 3, 1 , and X ray spectra. The absolute and relative intensities of 1 rays(569.7 Kev, 687.3 Kev and 898.0 Kev) were measured with a Ge(Li) detector claibrated for energies and efficiency. The absolute intensity of 569.7 Kev t ray was used for the determination of the total activity of 211At product. In a single production run ( 17 A.h) about 2.2 mci of 211At was obtained after isolation. The content of 2*0po, an impurity, was measured, the ratio of 210Po/211At being lxlO"8.

The property and behavior of 2^At in aqueous solutions were studied through extraction with crown ethers. The following observations were made through experiments: 1. In the absence of reducing agents, 2^At was extracted effectively by crown ethers. 2. The distribution ratio D was dependent on the nature of halogen anions and pairing cations. 3. The extraction efficiency varied with different ions present in the orders of I">Br">CT and K+>Na+>Li+.

The extraction mechanism is as follows: 1. Formation of complex-anion AtXji (X=Cl,Br, I or OH). 2. Pairing of the complex-anion with M+ (M=Li, Na, K or H). 3. Extraction of the ion pairs into crown ethers in the form of MAtX2*L/Q\. The extraction reaction can be written as

+ AtX- + M + L(0)=MAtX2-L(0)

- 115 - M. Hussonnois, J.C. Krupa, M.P. Lahalle, T.. Rrillard, C. Lefevre, M. Genet, R. Guillautnont Instltut de rhysique Nucleaire, Laboratoire de Radiochimie, Bolte Postale n° 1. 93406 Orsay Cedex (Piance)

PRFXTNTNARY RESETS AB-9TTT "0- LT7TVIATTON

Study of UO_ lixiviatlon is just now being in progress in the laboratory In order to determine tne reaction mecTianlsm of no„ interaction with water (oxidation state of uranium species produced at the surface and in aqueous solution) and to answer the question : is it possible to predict HO, leaching when the contact with groundwaters is very long ? This problem is obviously related to the long storage of irradiated nuclear fuels. It is studied, for the first tine, from a basic point of view," with natural U02, and it is developed with different kinds of UO2 samples : powders, thin films and single crystals, freshly prepared or stored for several years- Thin films are obtained by evaporation from a molybden tungsten lined crucible, and single crystals from the melt carefully cooled. The stoechiometry of UO2 has been checked by ESCA. Analytical methods used concerned the solid state and the solution which has been in contact with during the lixiviation. Very thin samples of VOj (< 50 microns; are investigated by visible and electronic infrared absorption spectroscopy. We observed some differences on the lixiviated WO- at 90° C during one month, compared to the blank. We assumed that the hydrolized species, produced on the surface, are responsible of the different observed spectra. We intend to use Raman spectro­ scopy to get more information about hydrolized surface.

As the quantity of uranium expected to b« found In solutica is very low, we have developed radiochemical methods to obtain a solution in minute amount of "Otj. This isotope is produced by • nuclear reaction on thorium metal irradiated with protons of 34 MeV energy according to the process :

232 23 Th(p, 3n) °ra J^^"°T,-iL_* ^Th , ™Ra 17 d. 20,R d. 30min. 54 s.

After irradiation, the target is dissolved in HCl medium and chemical separation between thorium, protactinium and uranium, by anion exchange technique, is done. Then 230pa jg fixed on a column to get a "cow" which can be milked to get 230|j radioche- mically pure solution. From these solutions, we prepared uranium in tetravalent, pentavalent and hexavalent states, in order to study the chemical stability of these species a very low level concentration and also to set up experimental conditions for their separation by anion exchange or solvent extraction procedure. Finally, we also measured the uranyl ion at low concentration using the well known delayed fluorescence technique.

- 116 - Ling Daren, Dept. of Modern Physics, Lanzhou Univ. China Powell, J.E., Ames Lab., D. 0. E. , U. S. A. Iowa State University, Ames. Iowa 50011, U.S.A.

ON ALTERING THE LANTHANIDE CHELATE FORMATION CONSTANT SEQUENCE TO IMPROVE AM-LN SEPARATIONS IN CATION EXCHANGE ELUTIONS

The philosophy of resolving actinide-lanthanide mixtures via cation exchange elu-tion with selective chelating agents is considered in view of the lanthanide chelate formation constant sequences obtained with various ligands derived from polyaminopolycarboxylic acid analogues of bis(2-aminoethyl) ether-N,N,N',N'-tetraacetic acid. For this purpose, the stability constant data for ML and MHL are reported for a newly synthesized variant, bis(2-aminoethyl)ether-N,N,N'- tri(acetic acid)-N'-(3-propanoic acid), dubbed DETAP, with the lanthanide rare earths and yttrium from pHc values of buffer solutions measured at 25.00±0.05°C and 1=0.100. The nonlinear calculation method was employed in the computations. The data have been compared'with those for other chelating agents.

The first point of interest in these data is that the maximum in the DETAP stability constant sequence has shifted toward the lighter end of the lanthanide series. Y exhibits a ligand affinity depressed to the point that it appears that Y would elute nearly in coincidence with the light lanthani-de Ce. The minitmm Am-Ln separation factor can be inferred to be 1.3 in a conservative way.

Synthetic details for preparing the reagent are reported.

- 117 - Wut W.S., Qiu, L., Yang, K.S. Department of Modern Physics, Lanzhou University Lanzhou, China

STUDY ON ION EXCHANGE PROCESSES OF URANIUM AMD ITS ISOTOPE

The Kinetics of 235Uo|+—238Uo|+, Uo|+—H+ and UO^—H+ ion exchange processes was studied with wacrorecticular sulfonic ion exchanoe resin. It is clarified that the last two processes starts from film diffusion, then, gradually change to inner diffusion, but the first process begins with inner diffusion immediately as soon as dead time has passed. These facts could be explained by a boundary mass-transfer modle based on adsorption double layer theory; Inner diffusion coefficients D of these three processes were determined and the results show that coefficients U of the first and second process are nearly equal to each other and that of the last porcess remains only 1/5 as that of the second one. Theoretical explanations based on dissociation mechanism combined with infrared data and microreversibility principle are given for the results obtained.

- 118 - PARAMETRIC STUDIES OF URANIUM SOLUBILITY IN GROUNDWATER

K. Oilila

Technical Research Centre of Finland Reactor Laboratory, Otakaari 3 A SF-02150 Espco, Finland

The purpose of these experijnents is to study the effects of tl»e trost iitpor- tant parameters on the solubility of uranium in deep granitic groundwater under the disposal conditions of spent nuclear fuel- These are considered to be pH and redox conditions, and the composition of groundwater, especially the carbonate concentration. As a fuel sanple tlie unirradiated uranium oxide pellets are used.

The solubility of uranium in ttie tv*> different synthetic groundwaters "was measured as a function of pH and redox conditions at 25 °C. The synthetic groundwater I is meant to correspond to the undisturbed chemical conditions deep in the granitic bedrock. The synthetic groundwater --II simulates the effects of bentonite clay which ha3 been proposed to be used as a buffer material. The increased carbonate and sodium concentrations are descriptive. The pH values of the water, were chosen so. that they represent the different carbonate, equilibriums, ac the solubility was measured at the pH values 4-..5, 8...9 and 11...12. The redox conditions vary frcm strongly reducing to mildly oxidizing conditions.

The experiments were carried out under air-saturated conditions, and under oxygen-free conditions in an anaerobic glove cabinet and in an autoclave system which was developed far the simulation of deep groundwater conditions. \ redox sensitive electrode couple was developed for this system.

The solubility limit or the equilibrium solubility of uranium was measured in the following way. The UO, pellet was dissolved in synthetic groundwater for a period and after that the water is changed. At first the water changing is done more frequently in an attempt to remove more soluble material, e.g. any higher oxides of uranium that might be present on the surface. Then the dis­ solution period is lengthened. Successive dissolution periods are carried out until the equilibrium solubility is attained or the solubility does not in­ crease anymore.

The solubility of uranium in the synhetic groundwaters at different pH values in reducing conditions varies from. 15...150 |ig/l, being at its lowest at the pH value of 8...9 expected for deep groundwater. Surprisingly, it lias not increased in the synthetic groundwater- II with the high carbonate content. The uranium solubility in reducing conditions varies from 1 to 10 py/1 being 1...3 orders of magnitude lower than in oxidizing conditions. These prelimi­ nary values are for the latest dissolution period of 165d. The results of the next period of 210d will be included in the presentation.

- 119 - Keith W. Fife, David F. Boversox, Dana C. Christensen, Joel D- Williams, and Herman D. Ramsey. Plutonium Metal Technology Group, Division of Materials Science and Technology, Los Alamos National Laboratory, P. 0. Box 1663, MS E511, Los Alamos, MM 87545 USA.

REGENERATION AND RECYCLE OF SPENT Pu02 REDUCTION SOLVENT SALTS USED IN PYROCHEMICAL PLUTONIUM RECOVERY OPERATIONS AT LOS ALAMOS

Los Alamos routinely uses batch pyrochemical unit operations to produce a puce plutonium metaL product from a variety of impure oxide or metal feed streams. The operations consist of controlling oxida­ tion, and reduction reactions between plutonium metal and its oxides or chlorides in a molten solvent salt.

Direct oxide reduction fT>0R) produces an impure metal product from the impure oxide according to:

11CaCl PuO, + 2Ca° 2,, Pu° + 2Ca0.11CaCl2 (1) 2 850°C Because of the limited solubility of CaO in CaClj (MO wtZ), the sol­ vent salts are discarded after each reduction. Advantages exist for developing a pyrochemical procedure to regenerate the spent salts; briefly they include: a) reduction of process vaste of ^0 7. b) improvement in overall process recoveries c) potential for pure solvent salt production d) potential for pure metal production from pure oxide sources e) potential for semi-continuous process development f) potential to fix excess calcium metal for ultimate disposal.

We have developed a procedure to regenerate the spent process salts which consists of sparging anhydrous HC1 or chlorine into the molten salt. The technique effectively regenerates >5 kg of spent salt in approximately 1.5 h using flowrates of between 3 and 5 £/min. Results from recycling these regenerated salts back into DOR are very encouraging. Using both foundry grade Pu02 (^5 % pure) and pure Pu0£ (>99 7. pure), we have been able to effectively reduce the oxide to metal. Recoveries average >95 %, which are comparable to yields from our production DOR process which currently uses the sol­ vent salt only once. We are in the. process of demonstrating regeneration/recycle in a batch DOR operation. Concurrently we are incorporating the technique into the design of a semi-continuous DOR process which should Increase productivity while minimizing waste generation.

- 120 - Chen.Z.D., Liu.G.X., Wang.X.R., Wang.X.F., Lu,Z.D.,Yang,Y.S. Northwest Institute of Nuclear Technology Xian, China o<-H5fM?QXY-«<-MEIHYLBUIYRIC ACID A BETTER ELUENT THAN ^-HYDRQXYISOBinYRIC ACID FOR THE CATION-EXCHANGE CHROMATOGRAPHIC SEPARATION OF Am(III) AND Cm(III)

The capabilities of <*-hydraxy-c(-methylbutyric acid(HMBA) and

Many factors which could affect the effectiveness of Am(III)-Qn(III) separation using HMBA as eluent have also been studied in order to make HMBA a practical eluting agent and it is found that a quite satisfactory result of the cation-exchange chromatographic separation of An(III)-Cm(III) can be obtained using a eluting solution containing 0.3 to O.AM of HMBA in the PH range form 4.0 to A.U and in the temperature range from 25 to 70'C.

- 121 - Xu Genfu. Xu Jiazhong, Zhu Jinghua Beijing Research Institute of Uranium Ore Processing, Beijing. China

A STUDY ON THE ADSORPTION EQUILIBRIUM OF QUATERNARY AMMONIUM RESIN IN URANYL SULPHATE SOLUTION

By chemical equivalent method it is found that when equilibrium solution contains 120-480 mg/1 of uranium, 10-20 g/1 of total SO?" and the pH is at 1.5-1.9. the 4- 2~ mole ratio of U02(S0.)» /UO-tSO-)- on the resin is approximately 1-2:1. The value of n in the complex UO.(SO.)2~2n is 2.5-2.7. i. 4 n It has been found by infrared spectroscopic study that exchange reaction takes place if the loaded resin is pressed together with KBr, and it can be represented by the following equation:

R,Zn-„ 2.UO-tSO, 2 4) n + 2(n-2)KBr - R-UO-lSO.)2 2 4 2, + 2(n-2)RBr

+ 2(n-2)K+ + (n-2)S0^~

The amount of free SO. in the disk can be quantitatively determined by infrared spectroscopy. The value of n is calculated from the amount of uranium, the SO ~ adsorbed on the resin and the free SO2.- and is in agreement with that obtained from chemical equivalent method.

- 122 - Ai, H.T., Chen, S. , Tao, 2.Y., Lin, 2.H. Zhengzhou Food Institute Zhengzhou, China

THEORY OF KINETICS AND EQUILIBRIUM OF ION EXCHANGE- ADSORFTION AND MECHANISM OF EXTRACTING URANIUM FROM SEA-WATER WITH TITANIC GEL

An isothenaal equation for ion exchange-adsorption is derived by mass action law. The equation can be used to sum up empirical and semiempirical formulas of exchange- adsorption, such as Gapon Equation, Sips Formula, Langmuir Equation and Fretmdlich Formula.

In this paper, by adopting the ion exchange reaction to act as the determining step of the ion exchange adsorption kinetics, an exchange-adsorption kinetics equation is derived. It is verified by the results of a series of experiments in which uranium is extracted form enriched sea-water and natural sea-water with hydrous titanium oxide (titanic gel). This equation can be used to explain not only the results of tests which have been applied to prove fast intraparticle diffusion or liquid film deffusion mechanism, but also test data which can be explained by the co-controlling fast intraparticle and liquid film diffision, and as well as the kinetics data which can not be clarified by diffusion mechanism.

It is proposed that the mechanism of the exchange adsorption of uranium from sea-water with titanic gel is a cationic exchange reaction as fallows:

+ + ST1-0H + U02OH ^=: = Ti-OU02OH + H A method for calculating the quantity of exchange-adsorption at equilibrium is also given. - 123 - Xiar Y„X. Shanghai Institute of Nuclear Research Academia Sinica, Shanghai, China

INVESTIGATION OF THE SYNERGISTIC EXTRACTION OF URAtTCL NLTRATE AND THORIUM NITRATE BY MIXTURE OF DMHMP+HTTA IN BEN2ENE

The synergistic extraction of uranium and thorium by mixture of HTTA and some neutral donors has been reported in literature . However, there is no work reported on the synergistic effects of the HTTA+DMHMP(di-l-methyl heptyl methyl phosphonate) mixed system. In this paper the synergistic extraction of uranyl and thorium nitrates in nitric acid medium with binary-system of RTTA+DMHMP are studied. It is found that synergistic effects occur during the extraction of uranyl and thorium nitrates with the benzene solution of HTTA+DMHMP. The formation of binary n extracted complexes U02(TTA)2DMHMP and Th(N03)2(TTA)2 MHMP has been confirmed by the Job's method and the usual slope method, respectively. At a constant ionic strength the binary synergistic equilibrium constants are determined to be lgP=3.76 for uranium (t=ZO°C,/t =0.1) and lg(*=5.42 for thorium (t=15°C,M =1), respectively.

The synergistic effects of the DMHMP+HTTA system have been compared with those of the TBP+HTTA for thorium and TBP+PMBP for uranium, respectively. The results show that the synergistic effects of the DMHMP+HTTA mixed system are more effective than those of the other two systems.

- 124 - Qiaii, H.S., Bao, B.R. Shanghai Institute of Nuclear Research, Academia Sinica Shanghai, China Xia, J.X. Shanghai University of Science and Technology, Shanghai, China MECHANISM FOR THE SYNERGISTIC EXTRACTION OF URANYL .NITRATE BY NEUTRAL PHOSPHORUS EXTRACTANT (DMHMP) AND ACIDIC EXTRACT ANTS {ttQttHP, HEHEHP AUD HPMBP) Mechanisms for the synergistic extraction of uranyl nitrate with binary systems of neutral phosphorus extractant di-(i-methyl heptyl) methyl phosphate (DMHMP) and acidic extractants di-(2-ethyl hexyl) phosphate (HDEHP), 2-ethyl hexyl 2-ethyl hexyl phosphonic acid (HEHEHP) and l-phenyl-3-methyl-4—benzoyl-pyrazolone-5 (HPMBP) have been investigated.

The extraction reactions are derived from the experi­ mental results of the dual-slope method. Tne equilibrium constants of extraction reactions are determined to be logp12 =5.19 (HDEHP-DMHHP), 4.95 (HEHEHP-DMHMP) and 5.33 (HPMBP-DHHl'lP).

Pros the effect of temperature on distribution ratio, the thermodynamic functions -AH, A2 and ^S of these synergistic reactions are evaluated to be -3.36 kcal/mol, -6.98 kcal/mol and 12.4 cal/mol-K (HDEHP-DMHMP); -6.04 kcal/mol, -6.65 kcal/mol and 2.08 cal/mol-K (HEHEHP- DMHMP); -11.1 kcal/mol, -7.15 kcal/mol and -13.3 cal/mol-K (HPMBP-BMHMP) respectively. Mechanisms for the extraction of uranyl nitrate are discussed in terms of a cone-angle model. The SAS values of these synergistic extraction complexes are all situated in the stable region.

- 125 - Qian, H, 5., Bao, B. R. Shanghai Institute of Nuclear Research, Academia Sinica, Shanghai, China

SYNERGISTIC EXTRACTION MECHANISM OF THORIUM NITRATE BY NEUTRAL FHOSFHORUS BXTRACTANTtDMHMP) AND ACIDIC EXTRACTANT 2-ETHTTL HEXYL 2-ETHYL HEXYL FHOSFHONIC ACID(HEHEHP)

The mechanism for the synergistic extraction of thorium nitrate by neutral phosphorus extractanU

There are three kinds of equilibria in the, system

Th(NOj)4-HN05/HEHEHP-DMHMP-C6Hg

4+ Th + 4N0^ + 3DMHMP(0) == Th(N05)4'3DMHMP,0)

4 + Th * + 2NO3 + 2(HA)2(Q) =» Th(N03)2(HA2)2(o) + 2H

4+ Th + 2NO3 + 2(HA)2(Q)+ DMHMPJ0J ==

+ Th(N05)2(HA2)2-DMHMP(0j + 2H By dual-slope method, the equilibrium constants of these three reactions are determined to he log^-Q

=4.47 (DMHMP), logp20 = 4.90 (HEllEHP) and logg 12 =7.65 (HEHEHP-DUHMP) respectively.

From the effect of temperature on distribution ratio, thermodynamic functions a H, A Z and As are evaluated to be -7.H kcal/mol, -10.3 kcal/mol and 10.7 cal/mol-K respectively.

The mechanism for the extraction of thorium nitrate is discussed, k possible structure of synergistic extraction complex is proposed in terms of a cone-angle model. - 126 - 5. Zouad, M. Fedoroff", C. Loos-Neskovic laboratoire P.Sue, C.E.N. Saclay, 91191 Eif-sur-Yvette, France

'Centre d'Etudes de Chiaie Metallurgique, 15 rue 6. L'rbatn, 9440O Vitry-sur-Seine, France

FIXATION OF RADIOACTIVE ON ANTIMONIC AND PH05PHA70ANT1H0NIC ACIDS

Radioactive strontium is one of the fission products found in nuclear wastes. Among inorganic exchangers, polyantimonic acid ii known to retain strontium with a good efficiency, but with a slow kinetic. The purpose of our study is a comparison between this product and some new phosphatoantioonic acids in order to explain the fixation mechanisms and to select the most efficient compound.

We have studied thr?e products t -commercial hydrated antimony pentoxide (HAP), SbsOs, 2.54 Hs0, with a cubic pyrochlore type structure provided by Carlo Erba. -H3SbaP30i«, n H/0 (H3) , with a lamellar rhomboedric structure, prepared at the Laboratoire de Chimie des Solides, Universite de Nantes. -HaBbaPaOjo, 7.3 Ha0 (H5) , with a tridimensional orthorhombic structure, prepared in the same laboratory.

Kinetics of fixation, capacities, and distribution coefficients of strontium on each of these products have been studied. Equilibrium is reached after three weeks on the HAP and HS products for concentrations close to the capacity. The kinetic curves can be explained by a diffusion in the solid. For HAP HI also observed a fast kinetic in a first step, probably corresponding to a juper-ficial fixation. Equilibrium is reached" after one hour on the H3 product even close to the capacity. This fast kinetic is ixplained by the lamellar structure of H3.

The variation of the distribution coefficients as a function of pH is controlled by a 2H"-Sr'* exchange. This coefficient decreases in the order i HAP > H5 > H3.

A tentative choice of the optimal fixation conditions can be made after these results. However the use of these fixators is presently limited by their grain size and unstability in solutions. Further studies shall be directed.to this point.

- 127 - T. MUROMURA. T. ADACHI. H. TAKEISHI. Z. YOSHIDA. T. YAMAMOTO. K. UENO and A. ITO Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki. 319-11, JAPAN

PHASE BEHAVIOR OF SOLID FISSION PRODUCTS IN 0O2.FUEL

The chemical state of solid fission products was investigated using simulated spent fuel corresponding to 5% to 30% FIMA. The simulated fuel was made from nitrate solutions of simulated fission products and uranium through dryness and heat-treatment at 1,000° to 2,000°C under various oxygen pressures. The phases formed in the product were identified by X-ray diffraction analysis as a function of burnup, temperature and oxygen pres­ sure. The distribution of the elements was determined by elec­ tron microscopy. In the atmosphere of 4%H2+96%He, the perovskite type phase (Ba.SrJZrOj was precipitated in the product of burnup above 5% FIMA. The fission products Mo, Ru, Rh and Pd formed metallic inclusions consisting of two or more phases depending on tem­ perature, of which size was in the range of O.lum to 7pm. Most of them distributed at grain boundaries of the matrix. At 1,000° to 1,600°C, at least two metallic phases were iden­ tified: cubic(Pd alloy) and hexagonal(Mo-Ru alloy) phases. At 1,800°C, three phases were produced* cubic, hexagonal and tetragonal{M05RU3> phases. The formation of the tetragonal phase proceeded in the product of high burnups produced at high temperatures. - 128 - Luo Shangqeng, Pu Shigang, Jing Yaozhong, Wang Lian, Xue Qinghua, Li Xioufang, Qin Renwei, Qu Zhiming Institute of Atomic Energy, Beijing. China STUDY ON GLASS FORMULATION FOR VITRIFICATION OF HLW WITH HIGH CONTENT OF S0^~

A glass formulation has been developed. With the addi­ tion of an additive (1 wt/6 of Ad-1) , this kind of glass can incorporate 20 wt/6 waste oxides containing 0.131 M SO^~ at 1100°C.

The viscosity of the glass is 135 Pa.s at 1100°C. It has -4 2 high leaching resistance ( 10 Kg/m d, using SOXHLET method in distilled water for 28 days at 90 C ).good thermal, mechanical and radiation stabilities.The surface layers of the leaching specimens were investigated by electron probe.

According to the analytical results of off-gas system and glass products, 70-80?6 of the content from HLW goes into the off-gas system, while ZQ-3Q% goes into the glass form.

With this formulation there is no appearance of yellow phase during the melting process and in the glass products.

- 129 - Tang,R.\ ,.Sun-.B-N-

Ihp llnivprsity of Scipnce and Technology of ChinaTHefei Chang, C.Z. Institute of Beijing Chemical Engineering,Beijing

I I CAN!) FXniANGE AND SYNERGISTIC EFFECT IN URANYL EX1RAC110N

By the cone packing model,we may predict the existence of the following liqnnd exchange reaction:

U02Ac2.21BP + U02C12.2TBP *- 2U02AcC1.2TRP Ihe s'teric effect is the driving force for ahove reaction. L igand parking around the uranyl equatorial plane should be neither overcrowded nor undercrowded. The Sum of Fan Angles of ligands' around the uranyl equatorial plane,FAS,provides a useful criterion for estimating the steric crowding. The FASs of UO^Ac^TBP^,

lin2Ac2TBP,U02Cl2T8P2 and U02C12TBP3 are 198* , 162* , 1 58 and 194* respectively. Thus none of them is in the form or stable extract

complex. FAS of IJ02(Ac)(Cl)TBP2 is 178*which is in the region of most favourable packing. Therefore synergistic effect based on

formation of extract, complex U07(Ac)(ClMBP? in mixed acetate and chloride solution was predicted.

The above expect ion was confirmed by extraction of uranyl in the substrates of sodium acetate-acetic acid and ammonia chloride. Keeping the total concentration of substrates to be constant, synergistic extraction was found at 1:3 acetate to chloride ratio which shifted a little on changing the total concentration but kept -4 constant on changing concentration of the urany] inn from 3.97x10 mol.dnT" to 0.0206 mol.dnT'. Fxtract complex was proved to be U0(Ac)(Cl)TBP_ by using the slope method and analysing the crystalized compound. The similar effect was found with other extractants and diluents.

- 130 - By. I. Bayat

Atomic Energy Organization of Iran

DFTERMINATION OF STABILITY CONSTANT OF CERIUM AMD TRANS-

PLUTONIUM ELEMENTS WITH ORGANIC ACID ION EXCHANGE

AND SPECTROPHOTOMETRY TECHNIQUES

By usinq strong complexinq aqpnt Actinides can he separated from Lantanides in one stage process. Determination of their stability constants with organic acids specially Amino-polycarboxy1ic acid is very important. The purpose of this research work is determination of the stability constants of Cerium and Transpolutoniurn elements using Ion Exchange and Spectrophotometry methods. In this paper the stability constants of Am(1 11 ) ,Cm(I II ) and CP(III) with 8 -Hydroxy iminodiacetic Acidnill]DE),Taurin N,N,Diacetic Acid (H,TDE) and N-2 Picolyiminodiacetic (H PIDE) complexes at constant ionic strength have been investigated. By Ion exchange method, the stability constant nf chelates have been calculated on the basis of ligand concentration and distribution coefficient between resin and liquid phase in the presence and absence of complex and constant ionic strength and various PH. letravnlent Cerium like Americium and Curium with Amino-Polycarboxylic acid forms chelate which is soluble in water. By spectropho­ tometry method, Tetravalent Americium absorbs at 5032A0 wave length, and by adding complex and titrating it, new peaks will appear between 5032A0 and 5100AD. The" results obtained From these two methods have compared and show that the Ion, Exchange is very accurate method Tor stability constant determination. Ref: I. Bayat,KTK/1 970/1291 Polyhedron Vol.1,No.1112,pp.827-8 30,197 2

- 131 - Yu Zhi-4sii, Guo Gang, Feng Xi-zhang, Li Xing-fu Application Department, The institite of High Energy Physics Wang Ling-jin, Zhang Ai-zhen Institute of Beijing Chemical Engineering

COMPLEXES OF URANYL COMPOUNDS WITH PMBP AND AMIDES OR PHOSPHINE OXIDES

Synergistic effecLs have been found in the binary system (^-diketone/neutr-al ligand) in the extraction of uranyl- For a better understanding of the mechanism in extraction,we have prepared a series of new cocapounds UO^PMBP^L where PMBP is

2-phenyl-5-methyl-4-benzoylpyrazol-3-one, L=H20, CH3CH2OH,

HCONMe2,HC0N(C2H5)2,CH3CONMe2,CH3C0N(C2H5)2,C2H5C0N(C2H5)2,

((CH3)2N)3PO,(C4H9)3PO,Ph3PO, or other ligands.

The new compounds were characterized by chemical, spectroscopic and structural means. Our experimental work and the geometrical analysis based on the cone packing model do not confirm other , type of extract complex, U02(PMBP)2L2, or U02(PMBP)2L L".

U02A2L2 U02A2LJ FAS Steric overcrowding ua2A2

200-

iao

160

140 Steric undercrowding • • 30 1* 160 8 FA cf NOJ PMBP-

- a.3 2 - 3. Radioanalytical Chemistry

- 133 - K. GRUDPAN and C-G.TAYLOR Department of Chemistry, Faculty of Sci?nc>;,Tlip University, Chiang Mai THAILAND 50002 and Department of Chemistry and Biochemistry The Polytechnic, Liverpsol L3 3AF ENGLAND.

A RADIOMETRIC STUDY ON SOLVENT EXTRACTION QF CADMIUM USIN^ At.lQtMT-335

The separation of cadmium from other metals, especially line and mornutv. W«B lnve.atiq.ated using radiotracer techmq\jen 15m, Cd-109, Zn-65 and Hg-203 labelling). A liquid-ion exchanger, Aliquate-366,which is readily and economically available, was used.

Solvent extraction of cadmium as an ion-associated compound of the type [R.Nj [Cd X J where R.N is the cation of Aliquat-336, and X is an anion such as cyanide, iodide and chloride was studied.

Stepwise separation of cadmium from zinc and tnnrcury can be achieved when the three tnet&Ls are first extracted from nquaouq chloride solution with a solution of Aliquat-33S chloride in CCl : %Anc Is then stripped into aqueous solution containing Iodide and ethylenediamine : cadmium Is finally stripped into aqueous solution containing ethylenediamine alone, leaving mercury in th« extract.

Cadmium can be Btripped more conveniently into .1 perchloric acid solution. This leads to a sinple and rapid m«?tviod for the concentra­ tion of cadmium from an aqueous chloride solution : concentration factorH of at least one hundred may be achieved.

References

1. Petrow, G.H.and Cover, A., Anal. Chem. 1965, 37(13), 1659. i. Mcdonald, C.W.and Moore, F.L.,ibid, 19 ? 3, 45(6), 983. 3. Hcdonald, C.W.and Rhodes, T. , ibid, 19 "7 A, 46(2). 300. 4. Grudpan, K. and Taylor, C.G., Analyst, 1934, 109, 585.

- 134 - Yngv-e Albinsson and Jan Rydberg Department of Nuclear Chemistry, Chalmers University of Technology 41296 Gothenbura, Sweden

ON-LINE LIQUIP SCINTILLATION MEASUREMENTS FOR THE AKUFVE SOLVENT EXTRACTION SYSTEM

The AKUFVE is a laboratory device for fast equilibration and separation of ?-phase liquid systems, using on-line detectors for rapid measurements of metal distribution ratios. The "heart" of the system is a ?-phase liquid flow centrifuaal separator achieving ~ 99.9% exit phase purity with a hold-up time of ~ 1 s. Spectroscopy and gamma radiometry have mostly been used for metal detection in the exit organic and aqueous flows. A new measuring device allows the detection of soft beta- and alpha- emitting radiotracers. The principle involves continu­ ous withdrawal of a small fraction of each (separated) phase, 7-3 ml/h, to which is added hydrolysis and sorption suppressing acid and a liquid scintillator, after which the mixtures pass measuring cells (one for each phase) viewed by photomultipliers. The use of the new device is demonstrated by the systems

Pw{I!F}-N3(M)C?04 - di-j-ethylhexyl phosphoric acid (HDEHP) in n-heptan, and Am(III)-Na(H)C10, - acetylacetone (HAA) in chloro­ form. Reproducible D-values (within + 0.05 log units) have been obtained up to pH 10.

- 135 - 3 3 o a < a. 03 01 fD nj CO m H H« h-* H rt 3 3 H »TJ M P? ^ a > w X H» (0 cr fD 01 fD fD o X cr M X 3* CO CD 3 ar o 01 CD cr 3 Pi ^ PJ n cr (3 O rt rt rt M rt < rt o H« rr fD O 0) 0l n rr •o i M 3 H o> 01 CD H. 3* 01 fD c re fD H- CD 3 OQ n rt CU rr 3 fD CD o to n J5 ^ PI a 3 w 0 O H» H ft) H H. < CO H- 3* 01 3 O 3- O H. H M fD w (0 00 1 Cu 3 3 CO 3 0) H* CO rt rr fD H' CD 3 rr 3* M rt rt fD 3 01 fD 01 fD fD a PUiJ H H- PJ • H, H« cu 3 3 vj •tf •^ H- •y T) rr H. H-" a H- 3 z 01 H- f-. 01 CO CD (D O* cr CO o o a. cr H. C - CO • CO rr (3d > • 3 a* H- O C 3 r* H- ID O «j H H W t-* a fmD a. O Ml 0c1r a CO 0n1 •t> M c/> 3 ^ . • • o* cr (-• o 1 cr rr ^ H- fD < h-» «-<5 01 CO o n c h- fO h-« rt O H C X •Ha 3 - 3* tr* ja o 1 £ o c or CD CO 3* rr 0) rt> rr 3 01 r- cr 01 « a o ft fD O* Ml rt Cu 03 o c 3* 3* o CL M OO 8>« o rt 01 •T3 3 M. (D o «. o O CD 3 CD o M 3* • CO O* H fD O" H- 0l M H« •d CD Cu rr H 01 a s: o. a1 a c a CO (-•• CD 3 i Oi O 3 M* h - o 3 •^ rr a a CO CD ai H- o 3 * 01 o V! r- 3 Cu rt 3 TJ o4 3* K{ 1 a o a o c- n I- (D 3" H- H« OQ 3 fD c 01 H* C CD 3 c T3 o 3 y o 0i PJ o ti* a o ID 3 O O 3 rt rr 3 3 el­ rt rr 3 M C *< O H- H« n 3 X rr 01 fD fD rt H* H- (D CD »i rr 3 H- Mo CwD • o o s' n o 1 o a a> H- CO 0> (-» a 3 3 M. a* O H* 3 T3 H- 01 =r o H r-j CO « O rt 00 rt TJ 3 O fD T3 3 rr Mi O 0 rr H« 3 » fD 1 o cr f 3 CO CO 01 I- H- Ml 0i O CO CD H« O 4 01 o> n 1 cr rr tr rt 3 ro Q> 00 i- CD 3 CO 1 O 3 M n CD «. CD O 3 O s M. 3* H* cu fD 3 M. X 01 PI o ro Ml CD • o 3 3 fD Mi H > n CD M- a> 3 T3 fD CO t rr o M o rr CO rr 3 rt O z 3* 3 3 M IT) (-> n> rt H- H c U) (0 3* 01 3* K. O H. h- •z O 00 M- a. 3 (D 3 01 O > rr 01 O 3 CD H« fD M) H« CD « rr rr CO ro 3 3 H* cr 3 0> T3 CO 13 n 01 Ui PJ a 3 a O <*i T3 M a 0 M a a 2 •^ K« fD £ £ rt 01 O CO 3 (-• 3* CD CD 3 K. CD 3 an <: V

CO H* M. Ml fD Oi CO fl> K- TO I M < a> Cu rt> rr o rr 01 th o CO H- rt M £ a T3 H- « CO fD CD a 3 •b 01 01 ^" fD H- CO 01 M. rr cr H CD a o cr ft rt (0 T3 M. fD 3* CO cr ^ 3 M- Ml O (-•• 3 n i rr rr M H« 01 CO M Ha O O fD 0i fD h" 3 0 fD rt T3 S3 r1- 01 0 (0 o bee n ETRI C

Mi U CO H ogica l • 3 o 3 H- O O «r reratur e r c P wer e ar d

•-• th e r>. CD a O < sente d u> 3 •< Ml O 3 fD fD Ml O Ml H.B.L. Pettersson, R. Hedvall & E. Holm. Dept. of Radiation Phy/sics, University of Lund, Lund, Sweden.

RADIOCHEMICAL DETERMINATION OF Pb-210

A procedure for determination of Pb-210 in environmental samples has been developed. The method involves organic extraction in tri-n>butyl phosphate followed by ion exchange chromatography, where uranium, thorium, radium and are sequentially extracted from the lead and further processed. Pb-210 is finally electro deposited onto stainless steel discs and measured by beta counting of its daughter, Bi-210, where a windowless low-level gas flow beta counter is employed. Pb-212 is used as trace/* nuclide and typical chemical yields of 60-80 % are obtained. The lower level of detection for 95 % confidence level is about 2 mBq for a 1000 min counting time, which is comparable with alpha spectrometry.

References: E- Holm. Review of Alpha Particle Spectrometry Measurements of Actinides. Int. J. of Applied Radiation and Isotopes. Vol.35, No.4,~pp 285-290,1984. L. Hallstadius. A method for the Electrodeposition of Actinides. Nucl. Instr. and Methods in. Ph. Research 223, pp. 266-267, 1984.

- 137 - ELIEZER PAUL MIGNONSIN Laboratoire d'Application des Radioelemcnts - B 16 TJniversite de Liege SART TILMAN - 4000 LIEGE ( BF.LGIQUE )

ACCURACY OF HALF - LIVKS DETERMINED BY f-RAY SPECTROMETRY .

Scintillation counters or semiconductor detectors have been used to determine the halfV-lives of those radionu­ clides which decay through Y-ray emissions . From the literature , among *»0O determinations t 111 have been carried out by Y-ray spectrometry .The decay rates are followed for 1 to 15 half—lives. The periods derived from the equation A. = A .exp(-Xt.) (1) are given with precisions up to 5% and not depending upon the magni­ tude of the half-lives . The aim of this work is twofold : - firstly: determine whether or not these precisions can be improved by a closer control of the experimental conditions and especially that of the dead time , the counting time and the ratio activity/background . Indeed, dead time being taken into account , the fraction of the recordable background is not constant during the decay time , but is a function of A._1 . - secondly: assess the accuracy of the obtained results on both statistical and systematic errors basis . Our experiments have been carried out with a Ge-Ll detector using ; preset count , m*ltlchannel scaling single sweep , true time and live time counting techniques. For instance , in this latter case , the general equation derived from theoretical analysis is : A. = A .expC-Xt^-j )„K1-exp(-Ax))„exp(-XT ) + k, ,..(exp( X(x+Ti))-1)] / \ where x is the memory recording time ,T the mean dead time , "ki_

MEASUREMENT OF TRITIUM IN PINE MEEf>LES AND ITS APPLICATION TO ENVIRONMENTAL MONITORING

Development of atomic power reactors and fusion reactors will create larqe potential soutces Cor continuous release of tritium to the environment. Therefore, it is necessary to measure the tritium concentrations in a variety of environmental samples vithout delay. In accordance with the avove view, the authors studied first on the method of loe level tritium measurement in pine needles. The techniques thus established are applied to a number of actual samples. Tritium in pine needles is divided into two categories, i.e., tritium in tissue free water and tissue bound water. The former is easily collected by freeze-drying, but the latter requires combustion of dried samples. The combustion water is collected in a trap immersed in dryice-alcohol. The water thus collected is used for scintillation counting after distillation. We measured tritium concentrations in pine needles collected from 21 locations in all over Japan which are concidered to be far enough removed from the influences of nuclear facilities. In addition to them, the same procedures were applied to pine needles collected in the vicinity of nuclear facilities. Tritium concentrations in pine needles of ordinary locations are higher in tissue bound water than in tissue free water with the ratio, ca.1.5. The ratios are quite variable for the pine needles in the vicinity of nuclear installations suggesting that this method is useful for the environmental monitoring.

- 139 - H. Sakanoue, K. Konura, T. Masuda, A. Yagi and T. Tada. tow Level Radioactivity Laboratory, Sanazava University, Tatsunokuchi-machi, Ishikawa, 923-12 JAPAN.

?b-210 AND Po-210 IS EKVIROKKEXTAL SAMPLES AXD THEIR BEHAVIOUHS BY SMOKING.

Low Energy Photon Spectrometry O-EPS) was effectively applied to determine non-destructively the contents of 210Pb in various environmental samples and the relating samples, while ii(iPo was determined by alpha spectrometry after radiochemical separation following wet ashing, by adding 209Po as yield tracer beforehand. Different raw tobacco leaves produced at different districts of Japan showed the various levels of 2 ' °Pb and 2 * °Po according to the fallout levels at these districts, while tobacco leaves cultivated in a green house shot* lower levels. Commercially available total 16 brands tobacco produced in Japan and foreign countries (USA, USSR and China) were also analysed for their contents of 210Pb and 210Po and the interesting results were obtained to show the difference among various brands. In regard to these facts, accumulation of long-lived 210Pb on the ground surface has been studied to know the wash-out effect of precipitations to radon daughters. Rather higher accumulation (about 500 Ci/km2) was found for the samples, such as rice-field surface soils, lake sediments collected from the areas on the coast of Japan Sea. The concentrations of 210Pb and 210Po in air have also been determined by collecting aerosols with a Andersen high volume air sampler and those were found to be about 8-40 fCi/m3 and 1.4 fCi/m3 respectively. Furthermore, the behaviors of 210Pb and 210Po in tobacco during smoking were also studied by analysing the ashes, Cambridge filters inserted in the flow of smokes during automatic smoking and the air filter sample during practical smoking.

- 140 - V. 1. Shamaev Mendeleev Institute of Chemical Technology (Moscow) USSR

HEW POSSIBILITIES OF RAU10ANALY.UCAL CHEMISTRY.

In the last years a number of radioanalytical methods has been worked out which are much more sensitive and selective than radlo- substoichlometric methods. Such an increase in their possibili­ ties is owing first of all to the fact, that these methods allow considerable violations of substoichiometrie separation conditions.

The model calculations showed us that the sensitivity of such methods as Interpolation Method, Method of H.. KYRS, Isoconcentration Analysis and some others are close to each other and are 50-lOO-folds higher than that of the substolchiometrie Isotope Dilution Analysis (IDA). It was shown that the futher increase of sensitivity can be achieved in methods applying greater relative quantities of reagentst Method of Isolation with Different Quantities of Reagent, Radioisotope- Stoichiometric Method, Interpolation Method with Addition of Inter- ferring Elements. Comparison of theoretical sensitlvlties (confirmed by a number of experiments) of different radioanalytical methods was carried out and it was shown that in many canes their sensitivity is much higher than that of Activation Analysis or Atomic Absorption.

A number of methods applying non-isotopic radioindicators was worked out allowing to overcome the practical limit of sensitivity which is owed to insufficient specific activity of radioisotopes applied.

Comparison of theoretical selectivity of a number radioanalytical methods was carried out. It waB shown (and confirmed experimentally) that the selectivity of such methods as Calibration Curves Method, Interpolation and Comparative Methods is 100-200-folds better than that of subs to ichiome trie IDA.

Combination of some new selective and sensitive radiochemical methods with substolchiometrie preconcentration allow to solve nearly all difficult analytical problems.

- 141 - Zhang,Y.H., L.iu,Y.G., Li.G.Q.» and Xiao.L. Institute of Atomic Energy. Beijing, China Xie.Z.C. Institute of Glaciology and Frozenland, Lanzhou, China

INAA OF TRACE ELEMENTS IN ANTARCTICA ICE SAMPLES

Trace elements in ice samples taken from Law Borne, Antarctica, were analyzed with instrumental neutron activation analysis technique. JUPITER multichannel analyzer-computer system coupled with Ge(Li) detector was used! for the acquisition of If-spectra and data reduction. "Blank" in water and nitric acid which were used in preconcentration and sample transfer were analyzed. To check the validity of this analy­ tical procedure, an U.S.EPA water standard for trace elements was analyzed. The observed values agree with the certified values.

The results show that for all 14 elements there have no significant change (increase or decrease) in concentration in the past 5000 years, indicating that the environmental pollution in other continents does not impact Antarctica considerably.

Elements such as Al,Fe,etc, are mainly derived from crustal materials. Na and Mg have marine origin. Observed high enrichment factors for some volatile elements are more likely the result of natural proces­ ses.

The enrichment factors for these 14 elements relative to crust show the similar pattern as that of atmos­ pheric trace elements at South pole, suggesting that the elements in ice are derived from atmosphere. Therefor the record of these elements preserved in the ice reflects the atmospheric element contents and their variation in the history.

- 142 - A; Chatt, K.N. DeSilva and R.E. Tout SLOWPOKE-2 Reactor Facility, Trace Analysis Research Centre, Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 401, Canada.

DETERMINATION OF TRACE ELEMENTS THROUGH SHORT-LIVED NUCLIDES USING A SLOWPOKE-2 REACTOR

Short-lived neutron acUvation products are being increasingly used for the determination of trace elements in a number of complex sample matrices. Both conventional one-shot and cyclic activation techniques using rapid transfer systems are being employed for this purpose. Detection limits and precision of measurements can be significantly improved by repeating the irradiation-decay- counting steps for an optimum number of cycles. Several problems such as variation of neutron flux from one irradiation to another, lack of accurate timing, presence of high activities and subse­ quent coincidence losses, etc may arise in many instances, and need to be properly accounted for. A rapid pneumatic transfer sample recycling system has been designed and installed at the Dalhousie University SLOWPOKE-2 Reactor (DUSR) facility. A sample weighing up to 5.5 g can be easily transported from the DUSR core to a detector within 350 milliseconds. SLOWPOKE-2 reactor is particularly suitable for studying short-lived nuclides because of the exceptionally high stability, reproducibility and homogeneity of its neutron flux. A mathematical model has been developed to correct for coincidence losses in cyclic activation analysis. An easily operated computer program has been used to estimate theoretically the optimum timing parameters for a number of short-lived nuclides in different types of simulated sample matrix. These methods have been applied for the simultaneous determinations of several elements through their short-lived nuclides in a number of standard reference materials; the accuracy of measurement has been found to be well within ±7%. Details of the methodology for the use of 110-Ag, 79m-Br, 38m-Cl, 165m-Dy, 179m-Hf, 116m2-In, 207m-Pb, 86m-Rb, 46m-Scand 77m-Se in elemental determinations will be described.

- 143 - 3 a. •*• O rr CO to r-"< cr CO cr 0) a> c *-"v 09 ft) TJ H- ft a. Z 0 O to re ca 9 A O 3 A CO O « 1 r* re r^ r* re ft) o 3 i CO >fl rt 3 O 3 0) re e Ml p-> rr rr A e rr 1 (T 01 01 « < A A 3 rt a. A re O fl) ftl C 3 < o re ft. (B o M 3 i < 0) a. H 1 "< 13 re re >-• 3 •o 3* >tj M re 01 A f* i-» a: a 1 1 S Rl 0 3" M> CO 3" o to "O 1 »-• a (-* H» a 0 > ar-v^ t H- C 3 w a) H- 3 r| 00 a re t* h* rr A er O M> A. x: at A re 01 ft 3 IT H> HI \* •xS ft 1 a O* CO > -i m lb M« M« re to o re o> a> rota. re i-* 3 cu 3 01 re Ml H"0 1 a •a 3 C 0 < 3* a. ft re t o re 01 rr t» i-n X rr ^^ o •-•w s> re K re to 3 ft Mr O O 50 O M at 01 a M a c > M- re OJ 1 o ft 3 3 M> 3 0) !-• rt 0) i-h O o ft •H n M 3 i-> r-< 3 2 3 ? 3 3 r- o»-» O 3 O 0* r«* o 3 re CO rr * •i^* rr •-•«! rr ft a. t 0) o •a 3 A 3 CO H< 3 1 01 O" A< 3 U A 0) (0 r* K> 1 3 01 O P r>; - a. rr rr M» 01 H- •v c 3 in "t ft) re «# (X a. r(-t• CO O 0) re a rst O" rr H. 0 3* C 3 3 rr a O ft 0) re f- co to 3 rn 0 >*rt • • re 3 rr i-» re rr ft) CO O 3 fl) 1 Q.0Q 3* A 0) p* IT 3 3 3 is M rr O 3 cr sr a O H<- a> 3- r* 0 r** PI o. - 01 sa> re rr H- H" 01 i— re i CO CD 1 vj 0 >*i 1 a< a 0 3 3 0. ft= * cy] f M- r-» rr t» e H- A rr r—» 0 1-14 (0 H- o •-* i o (a rt> 3 a. o. re 3 •— a 1 0) r-« i •1 1 H» U 3 O w 0) 3 3 at N3 X 3 t H- e*-* re CO s CO rt TJ It a re re re O rr re 0) a. •1 Q> 3 3* 3 re M» !-*• 3 ai re re O »-* •« x re o •-• rr t c 1 i 3 3 t > M rr o >-» re A T3 o 01 CO 09 3 3 rr re ft) ID ft> n co re ft) O ft r* o r* rr O M hfl rr 1 to 0 CO 3 CO 01 3 3 3 « 3 O CD 3 rt i 3 *• CO <• 3 3" re A 3 3 » ft, g O 3 CB 0 H> rr C C CO m 01 C 1 (-• A rr 73 H- O / CO A rr CO H re •a rr S ft A) ft ft rr 3 ft 1 09 rr CO 3 3 IT* •*• r-» 0 cr 0) 3 O 0) •> 3 a. 3- 0) a ?r 3 a 3* 01 Co i—> ft) O re er )—* CO o at re H- ai o rr 01 ft A 3 r- C3 ft) a> 0) ft) n - rr m 1 C f A r-» 3 1 re re C 3 ca a. 3 r-» l-h CO >-• A 4>TJ 0 rt e- rr rr z» •a 0 3 re rr 3 i 01 ft i 09 I-* kt ie A « 3 r» O IT X ft A 3 r» PJ 3. Q 3*TI S> r| a 1 ca CO i 3* O •O rti •<: £* re 0) Co rt rr e 1 rt 1 ft 3 ft r*> > O 3* 3 01 re •v 01 rr re a. i re re £ re > O re re A re 3 TJ ^ • CO TJ A O »H ~a) A O K> •-• rr rr r» rtf Co m i 3 re(-• > W 3 o 0) r" O i rh h-» 3 3 M •O 3 ft CO O C O -O »-• 0 H- Bd CD rt 3 0 re re re>-• ca a H o i-» re rr M H> A< ocr 1 1 3 s re rr 3n 1 O cr re 3 i a 3 3 c u re 3 re« **CO^ a 1 a to- CO >"t ft CO • re CO r* 3 3* O re ^TJ •xj 3 X re rf re 1 •o Qa o ft) 3 PJ C rr O A 3 a rr re re 3 O.T3 H O rr ft) A H« 3 A a. re rr 1 3* H- 0 rt a CO • 1 rr 3 i o Itl re 3 i I-*- 1 ft) cr t-l CO 3 h-* t—««»-S> rr gi i—• re 0) r-* Ml H> h-* W^<3 3* IT «s 3> a • rt i-r C •o o o a> z re M- CO cr rr re -4 CO «5 k« o M • A 1 01 re O s 0) 3 3 HCTIO A » 01 V3 3 •«5 01 3 1 r» re 0) 3 •3^ > ft) 1* rr a r-» T. 3 a re to oi a 1 > a. 09 CeO rr re 1 re n N- CO -h o7) • 3 *H f TJ a. tr* V re 3* M O 3 ft) 3 o 0 1 9 a. to e i-l 01 i i-ri 3 3* 01 rr h-i o* re< n H- 0) a ftl z 3 rr ve, ft o 0) er o H o rr 3 01 ft)< C a. O c co >•>{ re re rr cr 6 rt CO re 3 M O M, >*v M H- H- ^ TJ 3 CO 1 a. !-•* 3-09 CO ^ r* o 3* 1-4 > CO 0) o* k* *i -4 ? M". i-h 0 r* r-" a o r* >-» CO so rfi ft) H- 0) •3 O i H» Z 0) > re 3) ft r> H» 3 0) z o 0 r— 3 3 re 3 O H- •d 0) co 3 0) re H- 3 si ft 1 3 rr X 3 re ID cr p. ft > < ••»• > ft co re e 3 A O rr M a. 1 o CO ft) rr 3* re fl re a PO re 3 o 3* 38 0 re«: CD O i-h A •o H« h-" O > 1 PJ re O rr OJ Mi 1 r* o Ua) 0) 3* ft) C 1 =r rt o 0•9 fti 9) ft) W CO ft) rr ^** 3 ft O oi ^re fl) re re ft) 0) >— w 31 i-^ CO IVJ"-: CU O cr h»* -o rr t« •M CO 1 3* r M- re 0«1 rr i o> H- ft CO 3 3 0 0*0 a re LJ a. ca • A H- Z M- rr U> ft) m CO 01 T» r~ 3" A i 1 re ft) a LJ ft) re (-• Ml M • ft) re — re ft O r* 0 r* iji 3) aPI IT 3 ca H- re •.CO 1 •o rr t— e w r. ^ a •o 3 i CO h* H- 3 o > 3 ft z 1 • 1 3 •0 IT 3* • 0) H* re «• 09 0) r-i CV5 •J •oM o - o re 3 «. re re M> O ft) 1 rr H« rr >->) oi o N i— h" 3 • ft) 3" IT 1 3 3 c C rr c(- • 3 rr 01 !-• A 3 1 X 0 ft re IT 1—• 1 3* 0 0) re 3 r-*» A o« 3" rr o 3" W n cr *• w 3 c ^ CO H «S O 3 3 3 r* ft) 1 M 01 H- a. A H- A A >-h z "J re 0)

1 sp o rt 6. Revel, N. Deschamps, C. Dardenne, R. Del mas Laboratoire "Piei-re SUE", C.N.R.S. -C.E.N./ Baclay 91191 - Bi-f-sui—Yvette Cedex, France

ULTRA-TRACE ANALYSIS BY NEUTRON ACTIVATION iAPPLICATION TO THE CHARACTERIZATION OF SILICON FOR SOLAR USE

An ultra-trace analysis method has been developed in order to define the minimum qualify required for *iiicion devoted to -fabrication of solar cells for terrestrial applications. This method use an irradiation in a neutron 14 _2 — i flux of 2-10 n.cm .s produced by the Osiris nuclear pool reactor at the C.E.N. Saclay. After irradiation, samples are carefully cleaned by acid solutions and their radioactivity is measured by gamma spectrometry using a semi—conductor detector characterized both by a great efficiency and a high resolution. Residual concentration in impurities of this silicon is very low, generally less than one nanogram by gram, so error causes are- very important. These causes have been systematically studied for each analytical step. The influence of numerous interfering nuclear reactions with silicon and its impurities have been calculated and measured in our experimental conditions. A particular attention was paid to the etching conditions to avoid every surface pollution after irradiation. The errors due to the measurement conditions and to the mathematical processing of the gamma rays are discussed. About forty elements can be determined in a same sample using a seventy hours irradiation. l'his method was applied to the determination of the impurities repartition in silicon ingots and study of the efficiency of the segregation process to remove these impurities when the starting material is an upgraded metallurgical silicon. The detection limits really obtained on electronic grade silicon arm in the range 10 to 10 g.g

- 145 - Iwamoto and T. Nozaki Thp Institute of Physical and Chemical Research Wako, Saitama, 351-01, Japan

CHARGED PARTICLE ACTIVATION ANALYSIS FOR SURFACE OXYGEN UNDER VARIOUS AMBIENT PRESSURES

Although surface? of solids are analyzed mosUy under a t\iqh vacuum, there are many important cas«=»cf to study surfaces under atmospheric pressure. For determining the quanti'ty of surface oxygen under various ambient pressures, we have utilized charged particle activation analysis with a suitable designed target assembly. 3 18 The reaction of ~"O16, j' He,p) F has been adopted for radioactivation- The He-3 particles are accelerated by a variable-energy cyclotron. The sample in the form of two plates in intimate contact with each other is placed on a water-cooled target holder and set in a bombardment chamber which can be evacuated. The incident particle energy is adjusted to g.ive the maximum cross section for the above reaction at the inside surfaces of the sample plates. The quantity of gaseous oxygen between the two plates was estimated to be much smaller than that of surface oxygen for any substance even under the atmo­ spheric pressure. " The substances we have analyzed are silicon, alminium and lead of high purity. The samples were pretreated by washing with acetone or by etching with acid or alkaline solution. They were bombarded with He-3 Particles (1^2 pA, 20 min) under the following eo B Pb: Acetone ambient pressures: O atmospheric pressure, about 10^100, 3 1.0-3 and 10 5 Pa. After bombardment,

the F-18 activity id in the forward sample 3 0.5 plate was measured non-destructively, 01 because the bulk X 0.1 o oxygen in the samples 1 is knwon to be negli­ o.o ; gible. As an acti­ vation standard a stack of Mylar films was used. The results -« -J -1 0 1 2 3 t 5 of analysis are shown log p in Fig. 1. Fig.l: Dependence of the oxygen quantity on the ambient pressure (pressure is in Pa unit) - 146 - W. D. Ehmann, W. R. Markesbery*, E. J. Kasarskis*, C. H- Thompson, V. E. Vance, S. S- Khare and Yi-XIan Mao

Department of Chemistry and *Sanders Brown Research Center on Aging, University >©£ JOent

SEQUENTIAL IRRADIATION NEUTRON ACTIVATION ANALYSIS APPLIED TO THE STUDY OF NEUROLOGICAL niSEASER

Brain trace element imbalances relative to age-matched controls have been reported in Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS) and related neurological diseases. Based on these observations, It has been suggested that trace element toxicity may he Implicated In the etiology and pathogenesis .of these diseases. Recent studies in our laboratory have shown altered concentrations of Br, CI, Cs, Hg, N, Na, P and Rb In AD brains compared to age-matched controls, while failing to confirm some Imbalances reported by others [1]. Our sequential irradiation neutron activation analysis (NAA) approach is designed to first take optimum advantage of high resolution gamma-ray spectrometry (IHAA) prior to employing radiochemical separations (RNAA). The irradiation sequence starts with the determinations of N and P by 14 MeV INAA, followed by two sequential reactor Irradiations for INAA determinations of Al, Ca, CI, I, K, Mn, Na, S, and V (t£ = 5s), and Ag, Br, Co, Cr, Cs, Fe, Hg, Rb, Sb, Sc, Se, and Zn (tj - 40h). Not all elements are determined in each type of matrix. Finally, the samples are again reactor irradiated for 40 h, dissolved in strong acids with the aid of microwave heating, and subjected to a rapid two-step solvent extraction and ton exchange separation procedure for the RNAA determination of As, Cd, Cu and Mo [2]. Me present here new data for elemental concentrations in specific brain regions strongly affected by AD (e.g., nucleus basalls, amygdala, hippocampus) and also In other body tissues and fluids of AD, ALS and control patients. Certain brain trace element Imbalances in AD (e.g. , Br, Na) appear to be reflected in fingernails and may provide an aid in diagnosis. Based on preliminary results, ALS brains show imbalances in concentrations of Cs, Hg, P, Rb, Cl, Fe and Zn as compared to age-matched controls. Five of these elements exhibited similar imbalances In AD brains. Hg is also found to be elevated in ALS blood cells. Sampling and handling procedures for diverse biological matrices and a unique statistical approach employed In data analyses will also be described.

|1] W. D. Ehmann, W. R. Markesbery, M. Alauddln, Tl I. M. Hossaln and K. H. Brubaker, NeuroToxicology, in press, 1986.

|21 Wei-Zhl Tlan and W. D. Ehmann, J. Radloanal. Nucl. Chem., 89, 109 (19R5).

- 147 - F.DE CORTE**, A. SIMON ITS**,, J-HOSTE* * Inst. Nuel. Sci., Proeftuiustraat S6, B-9000 Gent (Belgium) XX Centr. Res. lust, for Phys., POB 49, H-1525 Budapest (Hungary) + Research associate of the NFWO (Belgium)

'SHE k0-SrA»'KjyU»JiiA5riaM METHOD IN (O,V) ACTIVATION ANALYSIS : STATE-OF-THE-ART AFTER A DECENNIAL RESEARCH The k..—method was launched in 1975 as a comparator technique with high versatility and applicability towards irradiation and counting con­ ditions: k^—factors — experimentally accessible nuclear constants - are convertible to k-factors (cf. Girardi's definition), vhich are bound to an experimental set-up. In terms of absolute standardization, a k(. re­ places the set of frequently unreliable nuclear data. That k -measurements with <1% accuracy are possible, was cou Lit tied Lu a first series of results (1980)2 for the relevant gamma-lines of 15 aua lytically interesting isotopes. To detect and eliminate systematic er­ rors, measurements were performed in Gent (reactor THETIS) and Budapest (reactor WWR-M). Continuation of our efforts led to a second table (1984) for in total 72 isotopes, and presently this is extended and up­ dated for in total 94 isotopes - including measurements at the DR3 reac- tor/Denmark. Experiments for another 25 isotopes are in progress. The obtained results reveal, and new evidence is given, that the inaccuracy of literature nuclear data is indeed often unacceptable. The k_-values being the basis for the accuracy of the k-.-method, no less concern went to the extensions and practical aspects. This led e.g. to a catalogue2' of formulas - now extended — for complicated reaction/ decay schemes, and to the development of experimentally simple correc­ tion procedures related to irradiation and counting. Contribution to (n.y) activation by epithermal neutrons required the accurate redetermination of Ir\/°n values (now updated and extended), and the development of in-situ monitoring of the thermal-to-epithermal flux ratio (f), for which zirconium was recommended. "Next, a correction pro­ cedure was worked out for a non-l/E epithermal neutron flux, shown to be adequately approximated by a l/E'4™ shape. This led to the calcula­ tion of effective resonance energies (now revised and extended) and to the development of a-monitoring techniques'*, including in-situ deter­ mination with Au/Zc (now significantly iisprove-J). This, together with the redetermination of k^ and IQ/<7Q values for the Zr-isotopes, resulted now in the revision of the use of Zr for f- and a-monitoring. In 1981s, a conversion method was proposed of the detection efficien­ cies measured for points at large detector distance, to cylindrical source geometries and/or close detector distances. The method corrects for •y-attenuation as well. It requires a cylindrical detector with known dimensions, a prerequisite increasingly taken into account by manufac­ turers. Also, a correction method for true-coincidence was developed. Considering all sources of uncertainties, the accuracy of the ^-stan­ dardization was estimated at < 4%, and this was confirmed in practice6. Results are given now for the determination of elements in zircaloy. It is concluded that the k„-method is at present a fully competitive standardization technique in (0,7) activation analysis. 1. A.Simonits e.a.,JRC,^4(1975)3I; 2. A.Simonits e.a.,JRC,M)(1980)461 3. L.Moens e.a.,JRNC,82(1984)385; 4. F.De Corte e.a.,JRC,62/1981)209 5. L.Moens e.a., NIM,187(1981)451; 6. F.De Corte e.a.,Isotopenpraxis 2£(1984)223 [jR(N)C = J.Radioanal.(Nucl.)Chem. ; NIM - Nucl.Instr.Methods]

"148- H. J. Ache Institut flir Radiochemie, Kernforschungszentrum Karlsruhe, Postfach 3640, 7500 Karlsruhe, Federal Republic of Germany

ANALYTICAL RESEARCH AT THE INSTITUTE OF RADIOCHEMISTRY, NUCLEAR RESEARCH CENTER KARLSRUHE, FRG

A review will be presented or the various analytical techniques applied to the solution of chemical problems within the ongoing research in energy technnlnny-*t the Institute of Radinchennstry, Nuclear Research Center Karlsruhe, FRS. Their advantages or dis­ advantages will be demonstrated by the discussion of typical applications. Special emphasis will be given to the use of ICP- Emission-Spectroscopy and Laser-Raman-Spectroscopy or -Fluorimetry for the analysis of non-irradiated as well as spent nuclear fuels.

- 149 - P.OeBievre.lvl GaBet. A. V*cbrugg*c«.f*. Oamen. W. Lycfce

Commission of the Furopean Commurwfies, Joint Res»anh Centre.Geel Establishment, Central Bureau for Nuclear Measurement*. B-2440 Geel. Belgium

"UNCERTAINTIES" AND "CERTAINTIES" IN ISOT0P1C MEASUREMENTS OF URANIUM-. KEYSrOACCUKACT

A review is given of the wide dynamic tango of U isotope ratios which have to be measured nowadays. The parameters which influence the reproducibility of the mas* spectrometric moajuiemerirs are discussed. A number of sources of possible systematic error sis described and it is shown how they can be corrected for. It is also shown how a sufficient uncertainty estimate for unknown systematic error corrections can be achieved eo. in the chatactetiiation of Isotopic

Reference Materials. It is described how an apparently complicated system • polynuclidjc elements and different and changing isotope fractionation during mass spectrometry measurements • can. in lact. turn out to be an advantage in the pursuit of accuracy. The proper use of the correlations between the uncertainties of isotope abundances, the relation between isotope fractionation factors and their uncertainties for the different ratios can help to estimate not only the

"uncertainty" but also the" certainty" of a measurement result.

Some of the ways to achieve this will be presented in detail: the preparation, characterization of synthetic isotope mixtures to 0.01 % uncertainty, the use of these mixtures to calibrate the UF, and thermionic mass spectrometric measurements of candidate Reference Material batches. This approach also requires that minor abundance isotopes in highly enriched isotopes have to be accurately determined. Obviously this cannot be done by direct measurements. It is shown how this can be achieved through "spiking" the highly enriched isotope with an amount of a non- present isotope equivalent to the amount of minor isotope under investigation. This same technique is used to characterize the minor isotope abundances in the candidate RM.

Finally it is shown how the overall uncertainty is computed by properly combining all uncertainties from each step in the entire procedure. It is demonstrated how oveiatt uncertainties have been achieved on mU abundances of 0.07% or less.

- 150 - Dong.L.Y.. Ye. K.M., Gao, L.C., Bi. S.L- Beijing Research Institute of Uranium Ore Processing, Beijing, China

STUDIES ON DETERMINATION OF ULTRATRACE URANIUM IN PYROPHOSPHATE SOLUTION BY LASER FLUORIMETRY

In this paper the molecular spectrum of urany] pyrophos­ phate was investigated- The highest fluorescent excita­ tion peaks of U0_(ClO.)_ and uranyl pyrophosphate (at pH 1 and 7) are 287,292 and 318 nm, respectively. It shows that the complexes of uranyl pyrophosphate are different at different pH. It is suitable to determine trace U in pyrophosphate solution at pH 7 by nitrogen laser fluori- metry. In the presence of CyDTA, the method is selective and sensitive. The detect limit is 0.01 ppb U, the preci­ sion of the method is +5%.

The laser Raman spectra of U0_C12 and uranyl pyrophosphate solution (at pH 1, 4.5, 7) in a quenching agent of HgCl_ was studied. The symmetric stretching vibrational frequen­ cy of (O=U=0) of UO~Cl_ is 870 cm" , and those of uranium -1-1 pyrophosphate at pH 1„ 4.5 and 7 are 840 cm r 835 cm and 820 cm- , respectively. It decreases with increase of pH. It shows that the negativity of (0=U=0) increases with the change of U0_ -- ligand ratio in complexes. The (0=U=O) forms a plane constitution with ligands, so that the conjugated system of %- electron of (0=U=0) is enlar­ ged and the efficiency of fluorescence of uranyl pyrophos­ phate is strong.

- 151 - N. Trautnann. F. /toes, ,J_ Bonn,. G_ herraann, H.-O. Xluge, E.-VJ. fltten, P. Peuser, H. Rimke, W. Ruster. P. Sattelberqer Institut fur Kernchemie und Inst.itwt fiir Physik. Universitat Mainz, D-6500 Mainz. Fed. Rep, Germany

DETECTION OF TRACE AMOUNTS OF ACTINIDES AMD TECHNETIUM BY RESONANCE IONIZATION MASS SPECTROMETRY

Laser resonant Ionization mass spectrometry has been u<;ed for the determination of trace amounts of plutonium, ai»it?i icium, curiiiw arid technetium in environmental samp)es. The method S<; based, on Uvr«e- step photoionization of the elements in the atomic state followed by a time-of-flight measurement for mass analysis. The system for photoionization consists of a pulsed copper vapour laser of 40 W a

- 152 - £. A. Hakklla and ft. G. Gutmacher Los Alamos National Laboratory Los Alamos, NM STS*1* USA

SOME CONSIDERATIONS IN APPLICATION"OF FADIOCHEHISTRT AMD NON-DESTRUCTIVE ASSAT IK IAEA VERIFICATION OF MATERIALS ACCOUNTING IN A NUCLEAR FUELS REPROCESSING PLANT

N»»r-R»ft! -Tf m»» nncount 1 ng h.»s be»n proposed for facility process control and domestic safeguards use In nuclear fuel reprocessing facilities. For a nuclear safeguards system that employs near-real-time accounting and Is under IAEA Inspection, all transfers Into and out of each materials balance area must be measured by the operator and Independently verified by IAEA Inspectors employing rapid, easy-to-use techniques. Verification can often be accomplished with radio-chemical or nor-destructlve assay techniques.

jpc ,. _.. r ...... -.., accountability tank, will not be discussed.

- 153 - T- X. Li Los Alamos National Laboratory Los Alamos. NM 87545 USA

A STUDY OF IN-LINE PLUTONIUM ISOTOPIC ANALYSIS FOR GASEOUS PLUTONIUM HEXAFLUORIDE

In-line plutonlum isotopic analysis for gaseous plutonium hexa- fluoride (PuFg) is very important for process control and special nuclear material accountability in any enrichment process that re­ quires plutonium .in a gaseous phase. Although much effort has been devoted to analyze arbitrary plutonium samples, no plutonium isotopic analysis has previously been done on gaseous PUF5 samples. We have initiated a study on the use of a nondestructive, high-resolution. gamma-ray spectroscopy technique to analyze high intensity, low- energv gamma rays at 43-48 keV for 238Pu, 51,62 kev for 239Pu, 45.23 24 for 24°Pu. and 148.6 keV for *Pu fr0m gaseous plutonium hexafluor- lde. The measurement system consists of a high-resolution hyperpure planar detector and associated electronics, a Canberra Series 90 multichannel analyzer with a 16-k channel analog-to-digital converter, and a Digital Equipment Corporation Micro/PDP-11 computer and peripherals. The computer, having 128-k 16-bit words of memory, is a processor for data acquisition and analysis. The hyperpure ger­ manium planar detector has dimensions of 1000 mm2 by 13 mm and a resolution (full width at half maximum) of 560 ev at 122 kev. The P11F5 gas was prepared by chemically reacting plutonium metal with fluorine. For the first time. PuFs gas samples with pressures vary­ ing from 0.01 to 2.5 torr, which were directly Fed into a 40C cc gas cell from a process flow loop, were measured. The Isotopic results of these measurements agree very well with those measured by mass spectrometry. Typically, within a 10-mln count time, the pr&cislon for a i-torr reactor-grade plutonlum hexafluorlde sample is 0.9% for 239Pu. 1.4% for 240Pu. and 2.5% for 238Pu and 24lpu.

- 154 - H. H. Stamm, H. Clatiss and H- D. Hanke Institut f. Radiochein., Nuclear Research Center Karlsruhe, F. R. Germany

EXAMINATION OF RAMOACTTVE SAMPLES WITH SEM AND XES

Ouring operation of the first Herman LMFRR (liquid-met nl-cooleri fast breeder reactor) KNK-II at Karlsruhe, numerous material samples have been exposed to the hot, flowing primary coolant*Na in various experiments. The aim of these tests was to find suitable materials for the removal of troublesome radionuclides from the sodium in radionuclide traps. The "deposition samples" had to be checked after the expositions for the deposited activities, and for morpholoqical and chemical changes of their surfaces. The deposited y -activities were measured with high-resolution Ge(Li)-de.tectors in connection with multichannel analyzers and a PDP-.il/3A computer. Morphological investigations were performed with a scanning electron microscope (SEM), chemical analyses with an attached energy dispersive X-ray analyzer system (XES). The radioactivity of the samples has a certain influence on the X-ray spectra. Especially radionuclides decaying by are of much significance. In our experiments, Mn-54 and Zn-65 are such radionuclides. After their electron capture X-rays of Cr and Cu are emitted. Without any excitation by electrons from the SEM, Cr-K and Cu-K lines are detected in the attaches XES. Naturally, the intensities of the Cr- and Cu-X-ray lines are depending on the activities of Mn-54 and Zn-65, respectively. In a series of Ni samples with different amounts of Mn-54 and Zn-65 deposited, this dependency is clearly demonstrated. With ] 1 MBq [D.3 mCi) Zn-65 on a Ni sample, the Cu-Ka peak had a comparable height as the Ni-Ka peak* with excitation by 10 keV electrons from the SEM. This was not important for the experiments with Mn-54 and Zn-65 on Ni, because the l

- 155 - Sha, L.M., Sun. K.X. Institute of Radiation Protection. MNI. Taiyuan. China

RADIOCHEMICAL ANALYSIS OF PROMETHIUM-147 IN DIET FOOD

A procedure for determining Pm-147 in diet food is described- The samples were ashed at 550 C. Nd and Sm were used as carriers because Pm has not any stable isotopes. 5-10g ashes with Nd and Sm added were leached with HN0-. Pm and RE were precipitated as oxalates and absorbed on HDEHP extraction chroma- tograph column after dissolving in HN0_. Pm was sepa­ rated from RE by using paper chromatography. Pm-.147 was measured with a flow counter, whose counting efficiency was 0.186, background 3.5 cpm. Nd and Sm were measured with spectrophotometry after coloura­ tion by arsenazo III to determine the chemical yield of Pm-147.

This procedure has been applied satisfactorily to the analyses for Pm-147 in 63 kinds of diet food including grains, potatoes, meat, vegetables,eggs, beans,tea, fruits, aquatic products and milk from 14 provinces of China. Average chemical yield was 0.814. The detec­ tion limit was about 3.4 x 10~ Bq/g (ash) when the counting time was 200 min.

- 156 - Luo Huanguang, Xie Ruiming, Zheng Keqiu Laboratory of Analytical Chemistry, Wuhan University Wuhan, China

SEPARATION OF THE RARE EARTHS, Cd(II),Co(II),Pb(II),Cu(lI), ZnCH) ,U(VI) AND Th(IV) BY THIN-LAYER CHROMATOGRAPHY

This paper reports a method for the separation of the rare earths,Cd

The spots of the rare earths, U(VI) and Th(lV) were located by spraying with tribromo-chlorophosphonaza as visualization agent. Detection limit is O.lAtg. Other ions of metal were located by spraying with dithizone or (NH^>2S as visualization agent. Detection limit is 0.2*g.

-157 - M.D. Glascock Research Reactor Facility University of Missouri Columbia, Missouri 65211 USA

ANALYSIS OF BORON USING NEUTRON-CAPTURE GAMMA RAYS

Boron is one of the least abundant elements in nature, the average amount in the earth's crust being estimated at less than 10 parts per million. Due to the lack of a suit­ ably sensitive analytical method, boron has rarely been reported. The technique known as prompt gamma-ray neutron activation analysis (PGNAA) has been developed in recent years to measure boron concentrations. Detection of the 477-keV Doppler-broadened gamma ray indicative of-neutron capture by the 10B nucleus permits analysis of boron. The boron detection limit is about 0.1 parts per million and a number of applications for boron analysis exist at the parts per million level.

- 158 - M. Ganz, L. Schmidt, S. Feige, D. Molzahn, G. Dersch, R. Brandt Kernchemie, FB 14, Philipps-Universitat, 3550 Marburg, F.R.G.

FAST DETERMINATION OF THE TOTAL AMOUNT AND ISOTOPIC COMPOSITIONS OF PUnONlW TRACES IN mirTEu URMtUWk AFTW HVKA.EM* FUE\. REPROCESSING

In nuclear fuel reprocessing, Np and Pu remain in very small quantities in Uranium after the extraction of fission products and transuranium elements. This reprocessed uranium solution contains quantities in order of magnitude of 10 g Pu/gU and 10 g Np/gU. We are developing a quantitative determination of transuranium elements Np and Pu in Uranium 239 240 241 as well as the determination of the isotopic ratio Pu/ Pu/ Pu. We developed an efficient and fast chemical separation procedure in order 8 9 to get decontamination factors of about 10 -10 . For the determination of isotopic composition we built a Time-of-Flight Mass-Spectrometer 252 working with Cf spontaneous fission induced ionisation. This technique has the advantage to be faster and more accurate in analyzing samples in comparison with other methods, alpha-spectrometry for instance. We show the present status of our technique: We can use thin foils (l-2um) as holders, as well as thick foils (100pm) as holders for our Pu-samples. A more generalized use of our Time-of-Flight Mass- Spectrometer for all kinds of isotopic analysis problems will be discussed.

- 159 - yj/erenngh, Y. te Duigou

Commission of the European Communities. Joint Research Centre.Geel Establishment. Central Bureau for Nuclear Measurements, B-2440 Geel Belgium

THE CHARACTERIZATION OF URANIUM ANO PtUTONIUM REFERENCE MATERIALS BY THE (100 - X) ROUTE. BASIC PRINCIPLE ANO APPLICATION

Uranium and plutonium reference materials are produced to calibrate reagents used in titrimetric methods or to check instrumental techniques like electrochemical methods. For this purpose, the most commonly prepared reference materials are high-purity uranium metal pieces and uranium dioxide pellets, respectively plutonium metal pieces and plutonium dioxide powders.

Two different routes can be followed to certify the element content in such materials: a direct or an indirect route.

With the direct route the main element is assayed using appropriate redox titration methods. The overall uncertainty on the main element is limited by both the piecision of the titration methods used and the uncertainty of the reference materials neces«saty to establish the o-xidiiing power of

the reagents.

The indirect route is applicable only for high purity base material. It requires the measurement of the sum of impurities (X) in the base material and the subtraction of this sum from hundred per

cent (100 - X). The impurities can be classified into major, minor and trace impurities. The elements

to be determined include both metals and non-metals. Since the (100 - X) route requires the

measurement of a large number of elements, a variety of analytical methods has to be used, and

different specialized laboratories are requested for their contribution. The following methods are

applied: spark source mass spectrometry, optical emission spectroscopy, inductively coupled

plasma emission spectrometry, atomic absorption spectrometry, molecular absorption

spectrometry, gas extraction analyses.

The uncertainty on the total sum of impurities is calculated from the respective uncertainties of the measurement of each specific element. If the total sum of impurities is sufficiently small and even if it is determined with a rather large uncertainty, the (100 - X) route leads nevertheless to a low uncertainty on the element content.

Advantages and disadvantes are described and illustrated for the case of a uranium dioxide pellet material certified as a European Community Nuclear Reference Material. Major impurities in this example were iron, silicon and carbon. Minor impuiities were , and molybdenum.

Trace Impurities searched for included more than sixty elements.

The (100 • X) method is recommended as a very accurate one for high purity material

characterization and certification purposes.

- 160 - -Wang -Yugt,, Sun Jingxtn, Chen Bingru, Tu Shude, Zhang Yuanji institute of High Energy Physics, fieademia Sinica, Beijing, China

DETERMINATION OF TRACE ELEMENTS AND THEIR DISTRIBUTION IN SOIL FROM THE TIANCHI NATURAL CONSERVATION AREA BY INAA

The Tianchi area located in Xinjiang (Uighur) is one of the major natural protection regions in China. Accurate determination of composition and distribution of various elements in soil is of great significance for environ­ mental protection, geochemical end pedological studies. In this work, 23 elements in soils collected from the Tianchi area were analyzed by INAA. The results obtained are illustrated as follows: 1. The contents of trace elements in top soils of this area have been determined. The results showed narrow variation in concentration for most elements, such as 8 RF.Es, Ba, Cr, Cs, Fe, Hf, K, Na, Rb, Sb, Th and U within a variation coefficient of 0.3 in this area except for As, Co.-, Sc and Zr. The average contents of elements in the Tinnchi soil are closed to those in the world soil. 2. The concentration of trace elements in six major types of the Tianchi soil exhibited increasing trends, i.e. Grey desert soi I < Mountain brown soi 1 <• Tvtounta in chestnut soil < Grey forest soi 1< Paramo soi 1< Alpine Meadow soil. 3. The correlations among trace elements have been calcu­ lated. The Zr-Hf-Na presented a significant correlation (p<0.05) and extremly significant correlations appeared for Rb-Cs, As-Sb, U-Th and Fe-Co-Cr-Sc (p< 0.001). The R-mode cluster analysis was also conducted for 8 REEs. They are basically divided into two main clusters, i.e. La-Ce-Nd and Sm-Tb-Eu-Yb-Lu.

- 161 - Qlan^X,^., Li.X.X. Institute of High Energy Physics,Academia Sinica, Beijing, China

COMPARISON OF TWO PRECONCENTRATION TECHNIQUES FOR NEUTRON ACTIVATION ANALYSIS OF NATURAL WATER

A new technique of low temperature evaporation precon- centration was used in neutron activation analysis for natural water- The technique has advantages of simpli­ city, low cost and high speed. Thus, it is suitable for the case of large amount of environmental water samples. The technique combined with neutron activation analysis was used in determining the concentrations of 24 elements contained in five natural water samples. The freeze-drying preconcentration technique was used parallelly for comparison. The results of these two different methods were consistent within the accuracy of +15% for As, Ba, Ca, Co, Cr, Cs, Fe, La, Lu, Mo, Na, Rb, Se, Sr, U, and of jf30% of Ce, Eu, Sb, Sc, Sm, Th, W, Yb, Zn. The results of the blank experiments show, that the environmental and reagent contamination is not serious. By the two preconcentration techniques, com­ bined with NAA, the NBS Standard Water sample, SRMl643a has been determined. The measured values and the cer­ tified values are cons IsSf.'P-t within the accuracy of +10%, thus confirming the reliability and accuracy of both preconcentration techniques.

- 162 - Chai,C., Ma,S., Mao,X. Institute of High Energy Physics, Academia Siniea, Bei j ing, China

SELECTIVITY OF CHELATING ION EXCHANGE RESIN AND ITS APPLICATION IN SEARCHING FOR IRIDIUM ANOMALY IN GEO­ LOGICAL novmmir.s

The chelating ion exchange procedure is suitable for separation of noble metals from base metals, but some­ one recently doubted the selectivity of the SRAFION- NMRR a popular chelating resin. In order to check the validity of the argument and to search for the iridium anomaly at Permian/Triassic boundary, we exten­ sively studied the performances of two Chinese thio­ urea chelating resins and compared them with that of the Srafion NMRR. Our results indicate that all three resins studied exhibit satisfactory absorption of Os, Ir, Pt, Ru, Pd, Re, Mo, Au, Ag and Cu. The amount of added resin, influence of the acidity on absorption percentage, selectivity of the resins for various ions, elution curves, elution of noble metals with NH„, the loss of Os in the separation and the effect of the Ir valence state on its absorption etc, were studied. The RNAA procedure reconmended on the basis of this work was used to determine the noble metals in some geological SRMs and the secondary reference clay samples. The exp­ erimental results confirm the feasibility of this pro­ cedure. Also, it was used to analyse the P/Tr boundary samples, Changxin, Zhejiang, China, and the high abun­ dances of Ir, Au, Pt, Re and Mo were discovered.

- 163 - S- Trebert Haeberlin *„ F. Lux *, J. Karl **, Th. Spruss **, H. Schonen- berger ** * Institut fur Radiochemie, Technische Universitat MUnchen, Walther-MeiBner-StraBe 3, D-8046 Garching, F. R. Germany ** Lehrstuhl fur Pharroazeutische Chemie II, Universitat Regensburg, UniversitatsstraBe 31, D-8400 Regensburg, F. R. Germany

APPLICATION OF NPJTRON AC1IVATI0N ANALYSIS IN DOSE-ACTIVITY RELATIONSHIP STUDIES ON PLATINUM-CONTAINING ANT1-CANCER TOWS

Neutron activation analysis (NAA) was used in the course of examina­ tions of the cytostatic effects of an cisplatin derivative with the oestropbilic ligand 1,2-bis(2,6-dichloro-4-hydroxyphenylEthylene- diamine. I.t was expected that this complex is enriched in the hormone- dependent mammary carcinoma because the level of oestrogen receptors in this carcinoma-is relatively high compared to unaffected mammary tissue. The NAA was used to provide information on the following topics: '.i) Determination of the platinum content (reference nuclide 1,9Au) of tumour tissue and different organs (mice and rats) in order to establish the distribution of the drug over the tissues of interest; information on the desired enrichment of the drug in the tumour was expected, (ii) Simultaneous determination of biologically important trace ele­ ments' contents (Na, K, Ca, Cr, Fe, Co, Zn, Se, Br', Rb, Mo, Cs) of the tissues in order to recognize possible changes of the occuring trace element level of tumour tissue compared with corresponding unaffected tissue, of organs of tumour-bearing animals, of tumour and organs under the influence of the therapy. The activation analysis procedure - separation of 3?P, isolation of 199Au and "Ho - is described. Dose- and time-dependent efficiency studies on the above-mentioned •drug were carried out with mice bearing MXT-mammary tumours (MXT mice) and Sprague-Dawley rats (SD rats) bearing DKBA-induced hormcne-

Research Reactor Institute, Kyoto University, Kuraatori-cho, Sennan-gun, Osaka 5°0—0

STUDY ON THE CHEMICAL SPECIES OF HALOGEN NUCLIDES BY A RADIO-ION CHROMATOGRAPHIC TECHNIQUE.

Halogen has many stable chemical species in aqueous solution. When oxyanion compounds of halogen were irradiated in the reactor with neutron, the elemental halogen and another ionic species different from the original conrpoands were formed by hot atom reaction. The reaction products of radioactive nuclides were very low concentration such as carrier-free state. Then the separation of the radioactive halogen in a state of such low concentration is very difficult with no addition of the carrier by the ordinary chemical separation method. It is interest in the field of solution chemistry to study on the chemical species of halogen nuclides existed in a state of the very low concentration less than ppra order. A radio-ion chromatographic technique was applied for the separation of the chemical species of halogen nuclides formed by the irradiation of the reactor neutron with a single ion exchange column of low exchange capacity. The separated ions were detected with both a conductivity detector and a radiation detector. The elements dealt with were chlorine, bromine, and iodine as halogen. Separation generally was achieved in only 20 min., and the sharpness of the eluted peaks was excellent. The changes of the percentage of radioactive nuclides as a function of the irradiation time in the reactor, temperature, phase state of tlie irradiated sample, and also the treatment condition of the irradiated sample after the end of irradiation obtained by the radiation detector were compared with that of stable nuclides obtained by the conductivity detector. Radioactive halogen nuclides existing in a state of high specific activity as reduced species could be isolated from the irradiated sample solution of the low radiolysis products under the short time irradiation by the reactor neutron. This technique might be provide a rapid and highly selective method for separating and determining the chemical species of very low concentration of radioactive recoiled atoms formed in nuclear reaction.

- 165 - R. Hedvall, B. Erlandssons& H. Pettersson Oept. of Radiation Physics, University of Lund, Lund, Sweden. ^Dept. of Nuclear Physics, University of Lund, Lund, Sweden.

DETERMINATION Of Pb-210 IN BIOFUEL ASK

Radiochemical separation, for alpha soectroscopy is often difficult, especially in the preparation of samples from tbp ashos of binfue?*. If the twcleids of interest also emit gamma-rays, measurements of these are preferable because no chemical separation or no tracers are needed.

This method is therefore advantageous for the activity determina­ tion of Pb-210 using the low-energy gamma-ray of 45.5 keV in spite of the difficulties associated with the efficiency calibra­ tion.

We have used a planar intrinsic germanium detector with a FWHN of 0.9 keV for the 122 keV peak in Co-57. The active area of the de­ tector is 1000 mm . The homogenized sample is packed into a 90 ml plastic tub and the radiation is measured for 1-2 days. We are analyzing, with this method mainly samples of ash from bio- fuels because of their high lead content.

References: Schery, S. et al. Anal. Chem. 1980, 52, 1957-58. Kim, K. et al. Anal. Chem. 1983, 55, 1796-1800. Roy, I. et al. Nucl. Instr. and Meth. 1983, 206, 553-562.

- 166 - Tong, C.H., Li, Y.N. Chengdu College of Geology, Chengdu, Ch ina

INAA OF REE IN URANIUM ORES AND MINERALS AND ITS APPLICATION

In order to minimize the fission interference of uranium and interferences from other radionuclides in the gnmma- spectrum, INAA of REE in uranium ores and minerals requires chemical separation before irradiation.

A target sample is made by dissolving the original sample in mixed acid, then treated by the following steps: cation exchange, solvent extraction and back-extraction. This technique was used in the following two examples.

Example 1 is a set of uranium ore and wall rock samples from the Lianshanguan uranium ore deposits.

The REE content in uranium ore is higher than that in wall rock and has a positive correlation with the uranium content. This is supposed ionic radii of intermediate REE are similar to that of The REE is enriched during uranium migration and precipitation.

The ratios of total REE in ore/REE in wall rock are different between samples from hypothermal deposits and those from epithermal deposits. Such differences help to understand the geochemical mineralization environment.

Example 2 is a similar sample set from No.3701 uranium ore deposit. The uranium source is inferred from the comparison of chondrite-normalized REE patterns between uranium ores and wall rock. - 167 - Yi, C.H.. Zhou. M.L-. Jin, S-S. . Xu, D.Q.. Jin, J.N. and Zhang, S.Y. Sichuan University, Chengdu, Sichuan, China A CHROMATOGRAPHIC SEPARATION OF ASTAT.INE-211 AND AN OPTIMIZATION METHOD FOR THE RADIOACTIVITY MEASUREMENT IN THE AUTOMATIC CHROMATOGRAPHY SCAN SYSTEM

An optimization method for the radioactivity measurement in Model FJ-2109 automatic chromatography scan system and a chromatographic separation of astatine-211 ar-e -reported To optimize the radioactivity measurement, the channel width and the scan speed are selected on two-dimensional "window diagram" and thus, there is a narrow region of the measurement conditions that will give acceptable radioactivity counts. The method has the advantage of convenience, efficiency and accuracy.

absorption chromatography of 211 At produced by irradiating target Bi with 27 Mev particles using 1.2 M cyclotron was investigated. After the nuclear reaction 209 211 Bi (o£, 2n) At, the target Bi was oxidized by oxygen at temperature 500°C and At was distilled by oxygen- nitrogen 1:1 V/V at temperature 720°C. On the silica gel column, the optimal isolation of 211 At was obtained by dry distillation in a special quartz still. Radio-TLC and paper chromatography of 211 At showed Rf values on the paper with dimethylformamide higher than that on silica gel G, silica gel H or aluminium oxide 211 with chloroform - methanol. The synthesis of At-uracil indicated.it could be prepared by free 211 At or oxidizing 211 211 Na At and the radiochemical yield was dependent on At concentration, reaction temperature and time.

- 168 - LlNDO,F.CHI DA.M.YANAGA.H.NAKAHARA.T.SUZUKI* and Y.I TO** Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Fukasawa, Setagaya, Tokyo 158. *Oepertntent of Energy Engineering, Hachinolie Institute of Technology, Hachinohe. Aomori 031, **Reseach Center1for Nuclear Science and Technology. Unversity of Tokyo, Tokai, Ibaragi 319-11

STUDIES ON ENERGY TRANSFER IN DIOXANE-PPO SCINTILLATOR SOLUTION WITH LIFETIME: MEASUREMENT AND PULSE SHAPE DISCRIMINATION TECHNIQUE

The energy transfer and energy loss mechanisms in scintillator solutions are not well understood because of the complicated chemical compositions- Dioxane-PP0(2,5-dlphenyl oxazole) system is one of the well known scintillator solutions solble with water. In the present study, the time spectra of the scintillation emission in dioxane-PPO solution excited with a-rays of 2<"Am and r-rays of 60Co were measured with a single-photon counting and a conventional coincidence system. We examined the effects of (1) oxygen, (2) naphthalene and (3) PPO-concentration on the time spectra. The observed lifetime spectra were analyzed with a least square fitting program into two components on the assumption that the mean time of energy transfer from solvent to solute molecules (PPO) is much faster than the rate of fluorecence emission from PPO. The results obtained for the oxygen effect on dioxane-PP0(1.45XI0"3 M)-naphthalene(0.7R M) are listed in Table. The mean Iifetime(T2) and the relative inlensity(l2) of the long-lived component observed for r -ray excitation were not affected remarkably by oxygen whereas the l2 for a-ray excitation was decreased. The results are compatible with those obtained by pulse shape discrimination technique, and will h^ interpreted in terms of different energy loss mechanisms for a- and r-ray excitations.

Table Oxygen effects on the scintillation decay of d1oxane-PP0-naphthalene solution excited with a-rays and frays*

2 Excitation source Oxygen 10»xx/s 10'T2/S 10 U** a-rays free 3.0 ± 0.1 19.0 ± 0.2 55.8 ± 2.0 sat. 2.4 ± 0.2 18.0 ± 0.2 34.1 ± 2.0 Y-rays free 2.8 ± 0.2 10.2 ± 0.2 28.1 ± 2.0 sat. 2.6 ± 0.2 11.2 ± 0.2 28.1 ± 1.9

•Naphthalene concentration 0.76 H **Relat1ve Intensity of the long-lived component

- 169 - Zhaj_PengX_L, Kang Tiesheng Institute of High Energy Physics, Academia Sinica, Bei j ing , China

TRACE URANIUM ANALYSIS OF VARIOUS WATERS BY FISSION' TRACK TECHNIQUE

This paper has given by fission track technique the results of the determination of trace uranium in various waters which include Beijing tap water, river water, atmospheric precipitation, spring water and lake* (or reservoir) water. In tap water, the uranium contents varied from 1.3 to 8.8 ug/lit; in river water, it varied from 0.03 to 1.30 ug/lit; in atmospheric precipitation, 0.008 to 1.5 ng/lit; in spring water, 0.006 to 1.62 ug/l. and in lake (or reservoir) water, 0.056 to 1.56 ug/lit. The results of the method have been compared with those of neutron activation analysis and others. The variety of the uranium contents of the various water source has been discussed briefly in the light of geographical environment. The standard deviation of the method is not greater than 10%.

- 170 - H. R. Das, Nuclear Chemistry Division, Saba Institute of Nuclear Physics, Sector-I, Block-'AF', Bldhan Nagar, Calcutta-700 064, INDIA.

SEQUENTIAL SErARATlOir AllO FRECOtJCCtJTRATIOH OF GOLD," TUNGSTEN AND MOLYBDENUM FROM GEOLOGICAL SAMPLES FOR UBTTROU ACTIVATION AMALYSIS

A suitable methodology involving solvent extraction separation and preconcentration of traces of gold, tungsten and molybdenum from some specific vnrities of geological samples lias been devlced. The chemical procedure involved, mainly, the steps comprising the digestion of the powdered rock samples" along with the tracers, Mo-99, W-187 and Au-198 as radioactive indicators for the corresponding elements, .in HF and aqua regia, treatment with alkali and tartaric acid and again with aqua regla. Gold, tungsten and molybdenum were then sequentially extracted from the aqua regia(diluted) solution with uhe solvents, MIBK, TBP and diethyl ether respectively under specific experimental conditions. The elements in different organic phases were extracted back separately into dl-1. HCl solutions and then coprecipitated with lead sulfide precipitates in presence of alcohol. Digestion of the powdered rock samples in HF and aqua regia helps in complete dissolution of the samples and also to keep gold in solution. Tartaric acid in alkaline medium keeps tungsten and molybdenum in solution as soluble complexes. The carrier PbS, due to its non-neutron active behaviour, acts as a suitable non-isotopic diluent for subsequent neutron activation analysis of the elements concerned. The recovery and the purity of the separated elements were verified by taking recourse to gamma-ray spectrometry of the respective tracer indicators.

- 171 - I. Hahadeviah. E. Mooney, James P. White TIT Chemistry Department, Youngstovn State University Youngstown, Ohio (USA) and Joseph Talnagi The Ohio State Nuclear Reactor Laboratory Columbus, Ohio (USA)

A NEUTRON ACTIVATION ANALYSIS STUDY OF WATER AND SEDIMENTS IN THE MAHONING RIVER

Elemental analysis of river water and sediment samples were performed to determine residual elemental pollution of the river system by the metal industries (primarily the basic steel mills). Water and sediment samples from 18 sites along the entire length of the river, plus 5 samples from entering streams were analysed. Elemental concentrations in the samples located upstream from the major industrialized areas and from entering streams (pre-industrial sites) were averaged and taken as background levels for the elements detected. Elemental concentrations in the samples downstream from the major industrial areas (industrial sites) were then compared to the background concentrations. Elements that are significantly higher than two standard deviations above the average concentrations of elements for pre-industrial sites are classified as pollutants. Using this criterion, 9 elements (Al, Sc, Cr, Mn, Fe, Co, Zn, Sb, Cs) were identified as pollutants in the river sediments and two of these elements (Fe, Zn) were found as water pollutants.

Sediment samples were analysed by neutron activation analysis (KAA) at the Ohio State University Nuclear Reactor Laboratory in Columbus, Ohio. Twenty-eight elements in sediment samples and twenty-two elements in water were Identified.

A comparison of these results with those obtained by a partial study of the same river using Californium-252 as a neutron source will be presented.

References 1. Muntean, R.A., M.S. Thesis, Youngstown State University, June, 1974. 2. Bart, G., Von Cunten, H.R., Determination of Trace Elements in the River Aare (Switzerland) by Neutron Activation Techniques. Intern. J. Environmental Ana. Chem., (1979), 6, p. 37.

- 172 - Ma^S^L^, Chai,C.F., Mao,X.Y. Institute of High Energy Physics, Academia Sinica, Beijing, China

PengTH-C, Lu,K.,First Institute of Oceanography,Na t ional Bureau of Oceanography Xiao,X.Y., Ouyang,Z.Y., Institute of Geochemistry, Academia Sinica

IDENTIFICATION OF IMF 'WIOIM OC T\\V W\CWV.T'\C, SI 1,1 PATH AND GLASS SPHERULES WITH TRACE ELEMENT ABUNDANCE

In recent years, studies of cosmic dust have been a very active field in cosmochemistry and astronomical geology, since it can provide valuable information about the origin and evolution of the solar system and Galaxy. The aim of our work is to use INAA for determining the concentrations of the siderophile and other trace ele­ ments in the glass, silicate and metallic spherules having different origins. It can be seen from the expe­ rimental resul.ts that the spherules exhibit different chemical compositions. For example, the concentrations of the siderophile elements, Ir, Os, Ni, Co and Au in cosmic dust are higher than those in the crust. REE and Sc in the silicate and glass spherules also exhibit unique abundance patterns. Thus, the determination of s ideroplii le, lithophile and other trace elements with iNAAmade it possible to decipher their origins.

173 - TuxSJ2-i W.«?ng,Y.Q. , Sun..J.X.. Zhang,Y.J. Institute of High Energy Physics. Academia Sinioa. He i j ing, China

NEUTRON ACTIVATION ANALYSIS OF TI1F. SOU. STANDARD REFERENCE MATERIAL FROM THE NAN.11AUAWA MOUNTAIN KX TIUF.'V

Ins t rumen t a 1 neutron activation analysis has been applied for the simultnnuoous determination of up 29 elements »n the "clean" soil standard, reference material (83-401) from the Nnnjiabawa Mountain (7782 meters above sea level) 'Region at Tibet, which was hardly ever influenced by industrial pollution and human's action. The procedure involved both short and long irradiations followed by the measurement of the gamma spectra with a Ce(Li) detector. The CRM's Soil-5 and SI,-1 (Lake Sedi­ ment) from the IAEA and SRM-1571 (Orchard Leaves) from the U.S. NRS were used as multielement standards. The quality of analysis was checked by analyzing the Chinese Environmental Standard Reference Materia 1-8 I 101 (River Sediment) and the U.S. SRM's 1632a (Coal), lfi33a (Coal fly ash). The analytical results of 29 elements in the soil SRM (83-401) are presented and discussed.

Reference 1. Tu.S.l)., Chni,C.F., Proc. 1st Nalionai Activation Analysis Conference in Chirm, August 1978, Atomic Energy Press, Reijing, China, 1981, p370. 2. Tu,S.D., W.llnnf, K.ll.Lieser, .1. Radionnal. and Nucl. Chem., 83/2 (1984) 407.

- 174 - H.Yoshj.kawa. K.Yamashita. K.Fnrio. H.Nakahara. M- Imamura*. and tt.Furukawa . DeparJaent of Cheaisiry. Tokyo Meiropoliian University. Fukazawa. Setagaya, Tokyo 158, Japan. * Institute for Nuclear Study, University of Tokyo. ^Department of Chmistry. Nagoya University, Japan.

RADIOCHEMICAL TECHNIQUES APPLIED TO THE STUDY OF VTII.CANIC GASES

Using natural radioactivities, ve can study the origin and the underground transport behavior of the volcanic gas. For example, two radioactive isotopes of radon are contained in the gas, and their concentrations are considered to be related to the Migration time and nixing of various gases existing underground. Those two isotopes offer two different time scale for the study of the gas. The chemical inert gas. Radon, has 222Rn(T|/2=3-82 d) and •20Rn(Ti/2=5.r« s) isotopes. They inevitably co-exist in the vol­ canic gas and are detected simultaneously . Ve have developed a simple and reliable method for thier determination using an espe­ cially designed portable liquid scintillation counter. Because of 22 the short half life of ^Rn, a Bethod for rapid sampling, sample preparation, activity measurement, and data analysis for the ab­ solute determination of the concentration was examined. On the other hand, we have also collected the Rn decay products from the gas and, after a simple chemical separation, measured the 212 2l4 radioactivities of Pb(T1/2=!0.64h) and Pb(T1/2=26.8m) with a liquid scintillation counter. Ve have compared this indirect method with the above direct method of the 222Rn and 220Rn measurement. Carbon dioxide is the principal component of volcanic gas, and it contains the radiocarbon ^t;(Ji/2=5730 y). It is expected that the ratio of '^c to '3C(or ,2C) .gives some useful information on the amount of the CO2 produced by the strongly acidic magmatic gas near the surface or on the mixing of atmosphere with the volcanic gas. Ve have tried the radiocarbon measurement using the method of accelerator mass spectroscopy. Ve tested those methods in the field for the study of hot spring gas and volcanic gas at 8 geothermal areas in Japan. Kimiko HORIUCHI. Tadashi ISHIIf Yuk-io MURAKAMI** Oept. of Chem., Faculty of Science, Tokyo Metropolitan University * Radi oisotupe Laboratory, Yamanashi University, School of Medicine ** Oept. of Chem., School of Hygienic Sciences, Kitasato University

A NEW DETERMINATION METHOD OF RADON CONTENT IN AIR WATER OR SOIL BY

A LIQUID SCINTILLATION COUNTER AND ITS APPLICABILITY IN FIELD SURVEYING

A new determination method of radon in air, water or soil with a liquid scintillation counter was devised, which consists of three main steps such as extracting dissolving of radon into toluene solution of liquid scintillator, establishing radioactive equilibrium between and its four descendants (2a+2B emitters) in a counting vial about 4 hours after dissolution and applying the integral counting technique with a liquid scintillation counter. This method can give five times larger sensitivity for the radon determination than that of radon only. The lowest detection limit of this method is 0.5 x 10~12Ci/l of radon dissolved, which give a net counting rate of 5.5 cpm by the integral counting technique. This method can simultaneously determine thoron (220j?n> half life 55.6s) content by rendering the activity measure within 80 hours dis­ solution of radon and by analyzing a composite decay curve obtained the lowest detection limit for thoron content is 6.8 x 10~10Ci/l of thoron dissolved. The applicability of this method were widely tested for the uranium prospecting, detection of cleavage or fissure in geological surveying, exhalation amount of radon from ground surface, measurement of leaking water from lake bottom and others. In this presentation the authors describe the outline of this method and also the results obtained for estimation of leaking saovnt of water from side bottom of a lake. The seepage water are firmly settled on the side bottom for collecting leaking water. The differ­ ence of radon content definitly show leakage of water from side bottom which are also supported by the difference of electric conduct­ ivity and chemical components and also geological point of view. Some of results obtained on study of pollution problem of a lake are cited in the following.

Difference of radon content according to water nature Seepage water Lake water Spring water St. No EC Rn EC Rn St. No EC Rn St. 4 184 72 71 5.4 St. 4 99 348 St. 5 64 494 69 3.9 St. 5 48 1655 St. 6 101 190 80 7.3 St. 5 57 2807 St. 9 123 36 52 20.4 St. 6 55 1734 St.18 161 51 101 14.4 Sr.14 70 253 unit EC : electric conductivity (uS/cm), Rn : pCil

- 176 - "Shiro 1WATA, Tadaharu TAMAI'H Research Reactor Institute, Kyoto University, Osaka-fu, Japan) "Takesaburo MORI, Yoshio KATO, Hazime SUGIIAMA "(National Institute •of Radiological Sciences, Cisita-shi, Japan) "Hiroshi IRIE"(University of Tokyo,Faculty of Medicine, Tokyo, Japan) "Yuichi ISHIKAWA "(Tokyo Medical and Dental University, School of Medicine, Tokyo, Japan)

RADIOCHEMICAL ANALYSIS OF THORIUM IN THE WHOLE BODY ANu AUTOPSY OF JAPANESE THOROTRAST-ADMINISTERED CASES

Colloidal thorium dioxide "Thorotrast" was first used as a radiological contrast medium in Japan in 1927. After 1930, Thorotrast developed by the German firm of Hyden was used widely at Japanese military hospitals and other medical institutes for angio- and hepatolienography to war-wounded military personnel. The use of Thorotrast in Japan is believed to have continued until 1954* The total number of Japanese patients who received Thorotrast injections between 1927 and 1954 is estimated to be 20,000 to 33iooo persons. Several kinds of malignant tumors, especially hepatic tumors were remakably obseved from about 1970 in the Thorotrast-administered group. Thorium contents of the patients were analysed by radiochemi­ cal techniques such as whole body gamma-ray spectrometry in connection with thoron radioactivity measurement of th° expiratory and neutron activation analysis of the pathological autopsies in relation to the X-ray microanalysis. The analysed results have been providing important data for radiological effects on the internal exposure by intake of alpha-ray emitters in human body. Those radiochemical techniques are reviewed.

- 177 - Chen BingKvm, Xu Jianyinj WuZhou isotope Development Institute, Chengdu,. China

SEPARATION AND DETERMINATION OF Sr IN URINE WITH

D2EHPA LEVEXTREL. RESIN

The paper describes the rapid determination of 90S r in urine. After the urine sanple is concentrated by carbo- nate coprecipitation, the 90 Y is separated with D-EHPA Levextrel Resin.Then, it is precipitated as Y2*C2°4*3 to measure 0-activity. According to thep-counts, the amount of 90 Sr in urine can be Calculated.

The method is simple and fast. The separation of Sr from Ca and Mg is satisfactory;the decontamination for fission elements is good. The radioactive recovery of Y is consistent with its chemical yield, about 90%. The lower limit of the method is 7.5xlO_2Bq/l.

- 178 - Wang Ling, Chen Mingxiu, Fan Meiying, Gu Lingxiang Uranium Geology Research Institute, Beijing, China

SEQUENTIAL DETERMINATION OF ISOTOPES oK If. Th, Ra AND Pb IN ENVIRONMENTAL WATER SAMPLES o(-spectranetry has been widely used for determination of U,

238U\228Th,230Th and 232Th, meanwhile emanation method for 224Ra, 226 22R Ra. The p-emitter Ac is used for determination of its parent 228Ra. As to determination of 2"^Fb, there are some direct and 210 indirect (by Po) methods. The sequential analysis involved all these radionuclides in a same water sample has been little reported so far.

In this work, 5 litres of water sample was taken and U, Th and Ra, Pb were concentrated by Fe(OH)., and sulfate respectively. The concentrated U and Th were further separated In a TBP-teflon support column followed by electrodeposition and o(-counting. After the BaSO, reprecipitation for separating isotopes of Ra from EDTA solution, to adjust the pH to 2.0, then most of interferences were cleaned away throuph the crystallization of excessive EDTA itself. Finally add F^CSO^K to EDTA solution for precipitation of PbSO.. The fl-emitter, 210 210 Bi, daughter of Pb, in the precipitate was measured several days later. The decontaniriation factor between Ra and Pb themselves is over 1000. 0.5g/l of calcium concentration can be tolerated. The detection limits for U, Th are ibjg/1, for 224Ra, 226Ra, 228Ra and 210Pb are 2xl0~2, 8x10"3, 4xl0-3 and 5xl0~3 Bq/1 respectively.

- 179 - Chen Da, Li Yinming, Zhang Zebo, and Tu Jing Northwest Institute of Nuclear Technology Xian, China

K* MEASUREMENT OF 21 ISOTOPES

Ko values of 21 isotopes used in reactor thermal neutron activation analysis were measured. These isotopes include 2Sa,A6Sc.51Cr.60Co.59Fe,65Zn,72Ga,95Zr,103Ru,110mAg, 122Sb,12WAWAW*^52Eu,17W7W81Hf. 182 187

Ta, W. Among these, the K0 values of 8 isotopes are first determined. The definition of K0 and measuring method are similar to that of Simonits* , but some are different, e.g. most irradiation target samples were prepared with solution dropped on the aluminum foil. The thermal flux and epithermal flux are obtained using the linear least square method by the activation rates of a set of isotopes instead of three isotopes or Cd-ratio measurement. The irradiation period was about 10 hours in reactor. T-rays are measured with Ge(Li) detector. The efficiency of detector has been calibreated with standard r-sources.

The accuracies of most K0 are less then 5%. These results agree with A. Ahmad's(2) within 2%.

(1) A. Simonits, L. Moens, F. De Corte, A. De Wispelare, A. Elek, J. Hoste, J. Radioanal. Chem. 60(1980)461-516 (2) A. Ahmad, P. Gray, T. D. Macmahon, M. Macwan, J. Radioanal. Chem. 72(1982)335-352

- 180 - Du, H.Y., Liu, B.B., Li, 2.L.. Southwest Institute of Nuclear Physics and Chemistry, Chengdu, China

DETERMINATION OF FOURTEEN RARE EARTHS, HAFNIUM AND TANTALUM IN GEOCHEMICAL STANDARD REFERENCE SAMPLES EY NEUTRON ACTIVATION ANALYSIS

In the present work, fourteen rare earths (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu ), Hf and Ta in six GSR geochemical standard reference samples have been determined by neutron activation analysis. The samples are separately irradiated with thermal and epithermal neutrons, the irradiation time is different for the different elements to be determined. After irradiation the V"-rays of various nuclei in the samples are measured by PHPGe and HPGe detector with S-80 multichannel analyzer and PDP11/23 computer.

Some samples are pre-concentrated before irradiation in order to determine the elements (such as Pr, Gd, Ho, and Er) that are difficult to determine with the method of the instrument neutron activation analysis. Average errors of the results are less than 15%. The method has been checked with American geological standard sample BCR-.1 .

- 181 - Mutsuo Koyama, Jitsiiya Takada and Takashi Matsubara Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-04 Japan

ACTIVATION ANALYSIS OF LAND PLANTS WITH SPECIAL REFERENCE TO THE PREFERENTIAL UPTAKE OF LIGHT OR HEAVY RARE EARTH ELEMENTS

More than 2000 samples of land plants and soils have been analysed by instrumental neutron activation analysis from biogeochemical point of view. As a result, more than ten new species and genus have been found to have capabilities of accumulating Co, Mn, Cd, Zn or rare earth elements. The comparison of distri­ bution patterns of rare earth elements in plants and in soils revealed that preferential uptakes of light or heavy rare earths are taking place. The characteristic of soils is an important factor to determine the total concentration levels of rare earths in plants. However, it was concluded that the preferential uptake is derived from the genetic nature of plant species. The accumulation of actinide elements will also be discussed in relation to rare earths.

- 182 - Naomi Aota and Koh Sakamoto Department of Chemistry, Faculty of Science, 1-1, Manmouchi, Kanazawa, 920 Japan

NEUTRON ACTIVATION ANALYSES OF DISAGGREGATED ALLENDE METEORITE AND OF JAPANESE GEOCHEMICAL STANDARD ROCKS

The carbonaceous meteorite Allende(CV3) has been known to record isotopic anomalies of a number of chemical elements in a variety of inclusions and/or mineral phases, especially for noble gases in some poorly-identified localized phases. An effort to isolate and identify the carrier minerals or phases for these anomalous noble gases and to aid deciphering the origin of these anomalies has been in progress in our laboratory. Our firstt step has been to disaggregate the meteorite samples by freeze-thaw followed by separation of the disaggregates by physical means : combinations of hand-picks, sieving, and density and sedimentation separations, and to classify the constituents in terms of major and trace elements determined by 14 MeV and thermal neutron activation analysis (NAA) and by EDAX coupled with SEM. In conjunction with this study, 12 geochemical reference rock samples recently issued by Geological Survey of Japan have been examined for up-to 30 elements by NAA. The results of these analyses will be presented and discussed in light of inter-sample and inter- laboratory comparisons.

- 183 - L.Moens, P.Roos, J.De Rudder, J.noste Institute for Nuclear Sciences, Proeftuinstraat 86, B-9000 Gent, Belgium P.De P-aepe, J.Van Eende . Laboratory of Geology, Krijgslaan 281, B-9000 Gent, Belgium H.VIaelkens Seminar for Archeology, Blandijnberg 2, B-9000 Gent, Belgium

INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS OF WHITE MARBLE

The main goal of this study is the characterisation of white marbles used in antique Greek and Roman architecture and sculpture; this will allow to determine the provenance of the raw material and reveal the economic and trade patterns existing in antiquity. A second goal is to contribute to the (hitherto limited) geochemical knowledge, on marble. The main quarrying sites of Italy, Greece and Turkey were thor­ oughly sampled and representative rocks are analysed petrographically, isotopically (C and 0 isotopes) and chemically. As to the latter ana­ lysis, minor and trace elements are determined using instrumental neutron activation analysis (complemented with classical chemical techniques and atomic absorption spectrometry, e.g for Si and Pb res­ pectively). A large number of quarry samples will be analysed thus creating a data base for geochemical study and for comparison of sam­ ples from artefacts. 12 To facilitate the ana.lysis, the kQ-method * is used for stan­ dardisation in INAA. An interactive computer code was designed for spectrum unraveling, interference correction, concentration calcula­ tion, etc., allowing fast and accurate routine analysis. The analytical procedure will be discussed and results will be presented for samples from different quarrying sites, demonstrating the possibility for provenance determination.

1. Simonies, A., De Corte, F., Hoste, J., J.Radioanal.Chem., 24, 31 (1975) 2. Moens, L., De Corte, F., De Wispelaere, A., Hoste, J., Simonits, A., Elek, A., Szabo, E., J.Radioanal.Nucl.Chem., 82, 385 (1984).

- 184 - M. Sk3lberg, fh Mandic, 6. Skarnemark Department of Nuclear Chemistry, Chalmers University of Technology, S-412 96 Roteborg, Sweden

FFNA - AN IMPROVED METHOD FOR EPTTHEP.MAL NEUTRON ACTIVATION ANALYSIS

At enithermal neutron activation'analysis (ENAA) the induced acti­ vity is caused by resonance absorption of ep]thermal neutrons. Many elements have high cross sections for resonance neutrons and are often found in matrices strongly activated by thermal neutrons. For such samples FNAA leads to a relative enhancement of the desi­ red activity compared to the matrix activity. A survey of neutron absorption data shows that the major resonance peaks do not over­ lap for a large number of nuclides. Consequently, we have investi­ gated the possibility of using additional filters at ENAA to furt­ her reduce interferences arising from epithermal activation with­ out affecting the desired activity too much, a method which we call filtered epithermal neutron activation (FENA).

The main requirement on such an additional filter is that the resonance peaks in its neutron absorption cross section spectrum do not overlap with the major resonances of the nuclide(s) which make up the sought constituent(s) of the sample. Furthermore, the filter thickness should he optimized in order to achieve a maximum reduction of the interfering activities in combination with a minimum distortion of the neutron spectrum in the irradiation position.

Experiments have hpen carried out to demonstrate the advantages of the FENA method. Mineralogical samples containing tungsten after being crushed in a tungsten mill have bepn irradiated using tung­ sten filters of different thickness. Similar irradiations were- performed using biological samples containing platinum. In this case filters containing sodium were used. The results show that a reduction of the interfering activity is obtained.

- 185 - Yan3» S.B.t Blan, S.S. Southwest, Institute of Nuclear Physics «nd Chemistry, Chengdu, China

DETERMINATION OF KRYPTOH-BS IN GAS FISSION FRODUCTS

BR A simple method of absolute determination of Kr has been developed with IIPGe G^mma spectrometer in this work. The detection efficiency is calibrated Jiy means of absolutely nteasuring the intensity of Its daughter 1 Rb, which is in temporary equilibrium with the parent. The overall uncertainty of calibration efficiency is less than 13%, A method of rapid op op separation of Kr and Rb from mixed fission products and each other is given. In this method we have used gas-liquid equilibrium technique and rapid drying method of -Rb source. The relative yields of Kr in i 239 pile-neutron fission products of Pu have been determined,/ which agree with the published data well. The overall uncertainty is less than ±4%.

- 186 - Noriyuki Momoshima, Yoshihiko Nagasato & Yoshimasa Takashima Department of Chemistry, Faculty of Science, Kyushu University 33, Hakozaki, Higashiku, Fukuoka 812, Japan A SENSITIVE METHOD FOR THE DETERMINATION OF TRITIUM IN URINE

A sensitive method for the determination of tritium in urine is necessary to estimate the radiation burden from tritium distributed in the body and to conduct epidemiol­ ogical studies of the tritium effect. Though there are some analytical methods for urine, they are mostly devel­ oped for the bioassy of relatively high tritium level. The present method is designed to determine low level tritium in urine on the basis of proper sample treat­ ments and liquid scintillation counting. At first urine is shaked vigorously with active carbon and filtered out. Coloring and smelling materials are effectively eliminated. The clear solution, thus obtained however, contained considerable amounts of metabolic materials. Total carbon analyses showed that the carbon concentration is more than a few thousand ppm. Additional treatments are carried out. The solution is distilled together with active carbon and distillate is distilled again together with KMnO. and Na~02• In both cases complete distillations are done to avoid fractionation. Carbon-14 isotope in the solution is expected to give no influence on tritium measurement because the total carbon concentration is decreased to less than 20 ppm. Mixture of 40 ml sample solution, 60 ml scintillation cocktail and 1 ml H2S0. in Teflon vial is measured by a low background type liquid scintillation counter. About 20 pCi/1 of tritium is detectable with 30 % of counting error.

- 187 - N. Matsuoka*. N. Shiraishi*. N. Momoshima**. T. Okai* *, Y. Takashima**

*Kyushu Environmtiital Evaluation Association.Matsukadai, Higashiku. Fukuoka. 813( Japan) * "Department of Chemistry. Faculty of Science. Kyushu University 33(Japan)

DEVELOPMENT OF IHE APPARATUS FOR THE MEASUREMENT OF KRYPTON-85 AND XE-133 IN EMERGENCY SITUATIONS.

Xrypton-B5 and xe-\33 are major gaseous products of nuclear fis­ sion. In paticular.krypton-85 has a long half-life, so that-it is an important nuclide on a long-term environmental monitoring. There­ fore the authors previously developed the apparatus which could neasure the concentration of krypton-85 in the atmosphere*'. The ap­ paratus was based on a chromatographic separation, and the beta-ray measurement of krypton-85 was done by a liquid scintillation oount- er(LSG).With the apparatus.it was possible to measure the very low concentration,but it takes more than 4 hours.On the other hand, in case of the accident of the nuclear facility, it is necessary to measure many samples as rapidly as possible, and xenon-133 will also become an important nuclide. In this presentation, we report on the apparatus improved for the stepwise measurement of krypton-85 and xenon-133 in emergency situations. The apparatus constructed consists of a molecular sieve trap for eliminating of water vapor and carbon dioxide, a charcoal trap for collection krypton and xenon,a separation column for isolation of krypton and a dissolution equipment of krypton and xenon into the liquid scintillator(IS).Ten liters of air sample containing 200 mi­ cro liter of stable krypton and xenon, is introduced into a charcoal trap immersed in liquid nitrogen passed through a molecular sieve trap with a vacuum pump. A large amount of oxygen and nitrogen col­ lected on a charcoal trap are removed by raising the trap tempera­ ture with water and flowing helium for 2 minutes. After this,krypton is carried with helium to a separation column and isolated from oth­ er gases. Next,krypton is dissolved into LS by the same way as shown in the previous paper*'. After this,xenon is desorbed from charcoal trap by raising the trap temperature to 100'C.and carried to a dis­ solution equipment without passing through a separation column.Fi­ nally xenon is also dissolved into LS by the same way as krypton.The recoveries of krypton and xenon are 40% and 53%. respectively. The measurement of radioactivity is done by a portable LSC.The counting efficiencies of krypton-85 and xenon-133 arc 63% and 47%. respec­ tively. By the above method.we can measure the concentration of 3X 10_,#Ci-cnr" within 1 hour.with coefficient of variation of 30%.

Reference *'T. Okai. Y. Takashima, N. Shiraishi,N.Matsuoka. J. Radioanal.Nucl. Chem., Articles. 81(1984)161.

- 108 - G.B.Baro; M.C.Rotta; H.Viirsoo. Comision Nacional de Energia Atomica Buenos Aires, Argentina.

DfiTEKHINATION OF CAMiA IMPURITIES IN FISSION PRODUCT MOLYBDENUM-99.

In Argentina the Atomic Enecpy CansnissJum hat, tee:: c.i ;.,•:. ^ . L.t ui years the production of Mo-99, necessary for elaboration of Mo-99/Tc-99m generators. Initially Mo-99 was obtained bv (n, if) reaction irradiating natural molybdenum, whereas at present the necessary technology is available for separation of fission products from enriched uranium targets, so as to be able to produce generators of high specific activity Qualitative and quantitative analysis of long-lived impurities is necessary as they are bound to be present as a consequence of production method. In this paper is exposed the methodology for analysis of long- lived gamma impurities in Mo-9? solutions produced by separation of • fission products*: The measurements were carried out in two stages: within 24 hours of ending production process, gamma spectra are analyzed by means of a solid state detector of high purity associated to a 2048 channel analyzer. In all analyzed experimental batches impurities never were above the detectability limit of the measurement method. For the second stage of analysis Mo-99 is allowed to decay for at least three weeks, so as to avoid gamma spectrum interference, its initial activity having been 3 mCi to 1 Ci. In the following table are given the impurities measured at least three weeks after production* showing the peaks used for measurement and their abundances: nuclide energy (KeV) abundsnee(X) *r»nyrities (ppw) Zr-95 756,73 99,9 <= 0,1 Nb-95 765,fto 54,6 «= 1 Ru-103 497,08 89,9 <: 20 I -131 636,97 7,15 •*£ 10 For the analysis of Zr-95 and Ru-103 the most abundant peaks were used. For 1-131 the ray of 636,97 KeV was used instead of the more abundant 364,48 KeV which would be close to 366,1 KeV of M-99. For Nb-95 measurements were made using the ray of 765,80 KeV after having allowed a decay time of nine weeks, as Mo-99 presents a gamma ray of 761,8 KeV of very low intensity (0,00252). The last column of the table indicates the proportion of gamma impurities for a given set of experimental batches expresed as parts per million with reference to Mo-99 activity. These values shoV that the quality of the fission produced Mo-99 is acceptable for generator production, alpha and beta contaminants being below required limits. Reference:"Table des radionuclides" L.M.R.I. - C.E.A. (1982/84)

- Iu9 - Yin Hong Qi Beijing Research Institute of Uranium Ore Processing, Beijing,, China

DETERMINATION OF TRACE, AMOUNT OF MERCURY IN DRINKING WATER BY SUBSTOICHIOMETRIC NEUTRON ACTIVATION ANALYSIS in this vjork, no volatilization \ass of trace mercury -which has been extracted with dithizone into chloro­ form is confirmed when evaporating the organic solution containing raercury. Based on it, a new raethod for the determination of mercury in drinkirig water is presented.

In the method dithizone solution in chloroform is used to preconcentrate mercury from water and then the residue from evaporating the extract is utilized as the irradiated form. The organic residue is sealed in a quartz ampoule and irradiated in a nuclear reactor at a thermal neutron flux of 5*10 13 n.cm -.se2 c -1 for 40 hrs. After irradiation the residue is decomposed with a small volume of nitric acid containing 3 mg Hg. The solution is evaporated to dryness. Then 3 ml of 10?6 H-SO. are added. Finally, the solution is shaken with a substoichiometric amount of dithizone (5«10 M) for 3 min. The gammma-activity of the extract is counted with a Ge(Li) detector connected with a multichannel pulse height analyzer. The amount of mer­ cury is calculated by comparing the net photo-peak acti­ vities at 77 kev in the sample and standard.

The content of mercury in drinking water in some areas of Beijing determined by this method is 80 ng/I."

- 190 - -. Chen Hen-An Beijing Research Institute of Uranium Ore Processing. Beijing, China

STUDIES ON POLAROGRAPHIC ADSORPTIVE WAVE OF URANYL-CUP- FERRON CHELATE MOLECULES

We have directly determined uranium in waste water , sla

We have studied the polarographic behavior of uranyl ion and cupferron in acetic buffer solution using single-s-weep polarography, cycle-voltammetry, stripping-voltammetry and chemical preparation. The sensitivity of determining ura­ nium increases due to multi-electron reduction of the complex active molecules-

It is assumed that adsorptive complex may*be neutral mole­ cules. Cupferron can be reduced with 6e or 4e. The product of electrode reaction is U(cupf).. It may be deduced that UO~(cupf)_ are adsorbed at the electrode. The reduction

of Uo2(cupf)_ might be the common effect of both U0_ and cupferron: two electrons participate the reduction of U(VI) to U(IV) while the reduction of 2 cupferron molecules needs 8e. So the polarographic sensitivity is higher than that without cupferron. It has been proved that ampere ratio of me solution, with the cupferron to without cupferron is 10.

This method might be a practical one according to deter­ mination results of ppb level uranium in various samples.

- 191 - Cen, T.H., Gu, M.J., Chiang, J.X., Tang, T.Y. Beijing Research Institute of Uranium Ore Processing, Beijing, China

THE SEPARATION OF IRON. THORIUM. PROTACTINIUM AND URANIUM WITH CL-5209 EXTRACTANT-CONTAINING RESIN COLUMN EXTRAC­ TION CHROMATOGRAPHY

The distribution coefficients of Fe, Th, Pa and U between CL-5209 extractant-containing- resin and HNO- or HCl solu­ tions were studied. Experimental results show that the distribution coefficient of Pa decreases with the increase of concentration of HF.

A procedure for the separation of Fe, Th, Pa and U was developed- The feed solution was passed through a CL- 5209 resin column-. The column was rinsed .with IN HNO, to strip Fe, then with 4N HCl to extract Th. Pa was then removed with 4N HC1-0.06N HF, while U was eluted with 0.3M (NH4)2C204 solution.

In this work, the distribution coefficients of Ra, Po, Ac, RE and other elements have also been studied.

This procedure is of special value for the simultaneous determination of all of the natural uranium and thorium series actinium isotopes with longer half-life. Some examples for practical use are given.

- 192 - Zhang, X.L., Liu, H.S.. Xia, K.L. Beijing Research Institute of Uranium Ore Processing, Beijing, China

RESEARCH FOR SEPARATING PROTACTINIUM FROM URANIUM AND OTHER IMPURITIES EXTRACTION-CHROMATOGRAPHIC METHOD USING QUATERNARY ftMMONIUM-Kel-F 2.31 Pa is one of the important natural radioactive ele­ ments. For the purpose of hydrometallurgic extraction of 231 Pa from slag, separseparatio. n of U and 27 elements from Pa has been'studied.

The tests were performed in a extraction-chromatogra- phic column. The column was made of polyethylene(inner diameter 4 mm). It was filled with Kel-F containing trialkylmethyl ammonium chloride. The height of fixed 233 phase is 6 cm. Pa was determined with f-counting method. 231 Pa with o<.-counting method, U with arsenazo- III colorimetric method, and other 27 elements — B,Li, Cd, Ba, Ni, Mn, Cr, Mo, V, Zr, Nb, Pb, K, Na, Mg, Ca, Sr, Al, Ti, Fe, Co, Cu, Y, Tm, Lu, In and Sc with spec­ trographs method.

The results showed that 27 elements can be eluted with

2 ml 6N HC1 and 1.5 ml 6N HN03, U with 3.5 ml 6N HNO-j. At last, 233Pa was eluted with 3 ml 8N HC1+0.5N HF. 231 Pa atyug level was used to verify the tests. The recovery of 231 Pa was 97.5%. This separation method is fast and safe. The purity of protactinium product can be improved over 1 to 2 orders by this method. It has been observed that F~ has influ­ ence on normal adsorption of Pa in the column. The inter­ ference can be prevented by HC1 evaporation.

- 193 - E. (lasanen and P. Manninen Reaclor Laboratory, Technical Research Centre of Finland Otakaari 3 A, SF-02150 Espoo, Finland

Determination of Total Organic Chlorine (TOCI) and Bromine (TOBr) In Water Samples by Adsorption onto Activated Carbon and Neutron Activation Analysis

A method was developed to determine organically-bound chlorine and bromine total concentrations (TOCI. TOBr) in water samples. The method is based on the adsorbtion of organic compounds on specially made" activated carbon. Neutron activation analysis (neutron flux 4XI011 n/cm?s) was employed for the quantitative detcrminiaiion of chlorine and bromine. The irradiation time for 100 mg of activated carbon was 300 s, with the delay and counting times 300 s, as well. Under investigation were the adsorption of organic chloro- and bromo- compoundson activated carbon, the effect of the pH upon adsorption, the removal of chloride ions from the activated carbon needed, the time of adsorption, the number of adsorption times and the preservation of the samples. The deicction limits for total organically-bound chlorine anil bromine were about 5 ;/g/l and 0.5 /'g/l, respectively, when the sample size was HX) ml.-

- 194 - Dr. J. Fodor ARWftFILT Industrial Cooperative Company Budapest XIII. Reitter Ferenc u. 37. Hungary H-1135

WEAR DIAGNOSTICS USING "£-RAY SPECTROMETRY

•Wear diagnostic system was worked out using -ray spectrometry of the neutron activated wear debris of i.e. engines. In the test procedure a sample of lubricating oil is taken from the engine, the sample is filtered on a membrane having 3 p pores and the residue is ashed and transformed into a mixture of ra­ dioisotopes by neutron activation, and then it is analysed by Q-ray spectrometry to determine the quality and quantity of components. The same procedure is used for analysing the res­ idue filtered in the oil filter of the i.e. engines. Using this techniques it was possible to determine: - the wear rate of i.e. engines in function of the quantity of abrasive contaminants floating in the lubricant, - the wear rate of i.e. engines in function of the particle sizes of abrasive contaminants floating in the lubricant, - the wear rate of i.e. engines with minimized influence of the abrasive particles. It was possible to assist the development of filters for i.e. engines (air filters, oil filters and fuel filters) to fully eliminate the effect of the abrasive particles on the engine wear; to considerably increase the engine life up to 10 km. The life increasing effect of these filters was controlled al­ so in fleet tests using the above mentioned wear measuring techniques. The use of these filters - called SF (superfine) filters - is widely'spread in Hungary.

- 195 - M. TSUKADA; K. YAMASHITA, M. YANAGA, K. ENDO, H. NAKAHARA. "Department of Agriculture, Meiji University, Tama-ku, JCanagawa, 214( Japan) . Department of Chemistry, Tokyo Metropolitan University, Fukasawa, Setagaya-ku, Tokyo, 158(Japan)

PRECONCENTRATION METHOD FOR NAA USING AN ACTIVABLE TRACER. — DETERMINATION OF LANTHANOID CONTENTS IN VARIOUS BIOLOGICAL AND GEOLOGICAL STANDARDS —

For the determination of trace elements in biological and geological samples by neutron activation analysis, some radiochemical separation is often required after the irradiation in order to get rid of the interfering nuclides in gamma-ray spectrometry. However, since such a chemical treatment is hazardous from the radiological safety point of view, it is preferable to pre-concentrate the trace elements before irradiation- One of the problems associated with the pre-concentration method is how to obtain the recovery yield. The authors have proposed the use of activable tracers to solve this problem(l), and demonstrated the feasibility for the determination of Cd. In the present work, the 21.6 % enriched 156-Dy is used for the determination of trace amounts of lanthanoid elements in biological and geological standard reference materials. The natural isotopic abundance of J56-Dy is only 0.0(5 % while the abundance oT 164-Dy is 28.2 %. Those two nuclides have large neutron capture cross sections and the produced radioactive nuclides emit gamma-rays of suitable energies with appropriate half lives. The 156-Dy doped sample was decomposed by acids or olkalines, and the lanthanoid were co-precipitated with iron hydroxide for irradiation. After irradiation, the lanthanoid were further purified by an anion-exchage column and by the fluoride precipitation step in order to get rid of the iron and other elements such as Sc. In the whole chemical procedure, other lanthanoid elements were found to behave similarly to Dy. The standard samples studied were: NBS standard Bovine liver, Orchard leaves, Wheat flour, Citrus leaves, Coal fly ash. NIES standard....Pepperbush, Chlorella, Human hair, Mussel GSJ standard JG-1, JB-1, JA-2, JG-2.

- 196 - Zhuang, G.S., Qui, Y.E. , Hua, Z.F., Cheng, Y.D. Shanghai Institute of Nuclear Research, Academia Sinica, Shanghai, China

CONCENTRATION AND SEPARATION OF NOBLE METALS ON CHELATING RESINS FOR NAA

In the present work, a scheme for selective separation on che-lating resins has been found and the adsorption behaviours of the noble metals are studied under static and dynamic condition using radioactive tracer. It is found that chelating resin coupled to a styrenedivinylbenzene copolymer, which contains functional group

-Ph-CH2-NH-C-S-S-C-NH-CH?-rn- s s shows high selectivity for the concentration and separation of noble metals from a large amount of base metals. The noble metals are quantitatively adsorbed on this resin (98,52 for Ag, 9B.3Z for Au, 93.OZ for. Os, 84.3% for Ru, 100Z for Pd and 97.71 for Ir). The resin does not retained Fe, Co, Zn, Rb, Cs, Sr, Cd, Ce and rare earths. High radiation stability of the resin has been observed after 60co Gamma-ray irradiation with maxium Doses of 10' rad.

The procedure has been applied to the determination of Au, Ag, Pt, Ru and Ir in anode slime, high pure copper and low grade noble metal ore by NAA.

- 197 - Du, H.S., Jia, Z. , Yao, L.N. , Zhou, "Y.P., and Xiao.L. Institute of Atomic Energy Beijing, China

PREPARATION AND MEASUREMENT INTERCOMPARISON OF STANDARDIZED RADIOACTIVE 241Am SOLUTION

The method for the preparation of standardized redioactive Am solution with simple constituents was developed. By means of HDEHP extraction and anion exchange, the highly purified Am (0.9999) was obtained. The « source for radionuclidic analysis with very high energy resolution (11.0 kev of FWHM) was prepared by molecular plating in our laboratory under the experimental condition different from that of other laboratories. A simpler and more reliable method for measuring the amount of nuclides adsorbed on the glass container surface was developed. This method also makes it easy to control the contamination. 9/1 The radioactivity of Am solution was measured with both 4TT«(LS) and 4TT«(PC) - T coincidence methods. The results obtained with the two methods are 482.11±1.llBq/mg and 481 -70±0-92Bq/mg respectively, which agree within 0.2X with the average value of the results given by other laboratories. The 4"n«thin film sources was prepa.r.ed by silica-gel electro-spraying. The detection efficiency (0.9988) is higher than those reported in the literature.

The results obtained in the trials and in the applications in different laboratories during the past four years have shown that our method is effective and reliable.

- 198 - Jiang, G.Q. , Yu, Z.J., Kang, M.X. , and Zheng, L.C. Southwest Institute of Materials Research, Chengdu, China Zhang, Y.H. , Liu, Y.G., Li, G.Q., and Xiao, L. Institute of Atomic Energy, Beijing, China

ISOTOPIC ANALYSES OF HYDROGEN AND OXYGEN FROM ANTARCTIC ICE. AN ISOTOPE CLIMATIC VARIATION RECORD FOR 5000 YEARS

The 180 and D isotopes in water are important climatic •jo -t g tracers. The ratios of 0/ 0 and D/H are governed primarily by the temperature at the time when the water was precipitated as snow. Studies on hydrogen and oxygen isotopic composition of polar ice provide a continuous record of past climatic variations. The £ curves of D and 180 determined from an ice core thermally drilled to 400 m on the Law Dome, Antarctica indicate relatively little climatic fluctuation in the past 5,000 years, with a mean value of -19.9%. for 180 and of -164 .5%, of K D. The annual surface mean temperature Tm is estimated to be -18.9°C.

- 199 - Chen,B.R., Yang,S.J., Qian,Q.F., Yang, Y.N. Institute of High Energy Physics, Academia Sinica, Beijing, China

DETERMINATION QF RARE EARTH ELEMENTS IN COAL SAMPLES FROM 110 MINES IN CHINA BY 1NAA

The abundances and distribution patterns of REE in coal mine samples can be used as a geochemical indicator,e.g. for exploring the forming condition of coal seam and comparing the seam with the stratum,etc. In this paper, 8 REEs(La, Ce, Nd, Sm, Eu, Tb, Yb, Lu) in the samples of 1J 0 coal mines in China were determined by 1NAA. A set of REE data in these samples was given. The quality was checked by analyzing the NBS SRM-1632a (coal fly ash). Our results reveal that the average values of REE contents in the Chinese coals are higher than those in U.S. coals. But the REE distribution of each coal mine in China is inhomogeneous. For exam­ ple, the total REE contents of some con 1 mines arc up to 400 ppm. but others are lower, nbout 20 ppm.

- 200 - Yang,S. J., , Qia.n,Q,F», Chen.B.R. , Yang„Y-N. Institute of High Energy Physics, Academia Sinica, Bei j ing, China

APPLICATION OF NEUTRON ACTIVATION ANALYSIS IN STUDYING ATMOSPHERIC PARTICULATE MATTER

Recently, in order to draw up measures for preventing and curing urban atmospheric pollution, the receptor mo­ del has been applied to identify main pollution sources. However, it needs a great number of measurement of trace elemental concentration in atmospheric particulates and in the emitted materials from various types of pollution sources. Activation Analysis is an analytical technique, being able to satisfy these requirements. In the past years, we have studied the physicochemical characteristics of atmospheric particulate and identified the pollution sources by INAA. The main results obtained are: 1. The concentrations of 40 elements in atmospheric par­ ticulate were determined by INAA. These data were app­ lied for studying regional distribution of elemental concentration in atmospheric particulate in the Beijing- Tianjin area and the variances of elemental concentra­ tion with seasons. 2. The elemental concentrations in the particles of dif- frent size in the Beijing-Tianjin area were studied and it was found that the toxic elements are mainly enriched in the f ine .par t icles with the dimension, of less than 2 um, which is easily inhaled by human. 3. 40 elements in 150 particulate samples collected at 8 sites in the Tianjin area were analyzed. The results cal­ culated by balance method indicate that the soil dust and emissions from coal-burning have the main contribution to the area in seven pollution sources.

- 201 - Luo,S.H., Ji,G-K., Xu,Y.P., Jiang,Y., Feng.X.Z. Institute of High Energy Physics, Academia Sinsca, Beij ing, China Chen,K.J., Zhou,W.Q., Li,C.S. Xiyuan Hospital, Academy of TCM, Beijing, China THE EFFECTS OF QING COURT SHOUTAO PfLL ON CONCENTRA- TIONS OF TRACE ELEMENTS Zn, CM, Na and Br IN HUMAN :-tAIR This paper reports the clinical effect of Qing Court Shoutao Pill on the concentrations of trace elements (Zn, Cu, Na and Br) in human hair. Twenty five aged patients (over 60) suffering from senile syndrome-complexes were divided randomly into two groups and treated with QCSP (12 cases) and Vit.E (13 cases) respectively. The concentrations of trace elements Zn, Cu, Na and Br in human hair collected before and after eight weeks of treatment were sepa­ rately measured with neutron activation analysis. It was shown that after eight weeks of treatment of QCSP or Vit.E, The concentrations of Cu and Na decrease, while the concentration of Zn remains almost constant, and thus the Zn/Cu ratios increase. This indicates that QCSP has the effect of slowing down aging, like Vit.E.

- 202 - Gary M. Sendquist Nuclear Engineering University of Utah - Salt Lake City. Utah. US JL

TECHNICAL DESCRIPTION OE METHOD EOR THE QUANTITATIVE ANALYSIS GE INDIVIDUAL EISSUZ CONCENTRATIONS USING FISSI8N TRACK COUNTING

Based upon earlier experimental research by Sandquist and Jensen- a practical means has been developed for distinguishing and determining the trace concentrations of natural uranium and of plutonium-239 "vhich are combined -vithin a single sample using standard fission track analysis techniques. This novel quantitative analysis method is applicable in general for all fissile nuclides and is based upon the differences fhich exist in the energy dependent microscopic fission cross section due to resonant behavior as typlified by Pu-239 and natural U. By exposing a sample standard containing knovn concentrations of both natural uranium and plutonlum-239 to a set of n(i2) distinctly different neutron energy dependent fluxes, a unique set of concentration coefficients, viz, aj j. ai2—ain- ^ 1-^22—-a2n can ^ determined as

U. Pu are the natural U and Pu-239 concentrations respectively Tj is the fission track count registered for the ith neutron energy dependent flux ajj is the ith concentration coefficient for the nth neutron flux

Vith the 8jj coefficients knovn for the sample standard, exposure of any other unknbvn sample to the same set of energy" dependent fluxes end determination of the respective fission track densities vill allov the individual concentrations of natural U and Pu-239 to be determined in the sample. A simple, but effective means of producing neutron fluxes of different energy vithin the sample is to surround the sample vith selected neutron absorbers such as cadmium, indium, gadolinium. hafnium,etc. The absorber covering thickness and practical number of independent energy fluxes (i.e„ absorbers) required to provide acceptable accuracy of this quantitative analysis method have been established and vill be reported.

- 203 - P. Hoffmann, Fachbereich Anorganische Chemie und Kernchemie, Technische Hochschule Darmstadt, HochschulstraBe <+, 6100 Darmstadt, FRG

APPLICATION OF RADIONUCLIDE SOURCES FOR EXCITATION IN ENERGY-DISPERSIVE X-RAY FLUORESCENCE ANALYSIS

X-rayfluorescence analysis is in broad application in all fields of science where elemental determinations are necessary Solid and liquid samples are analyzed by this method. Solids are introduced in thin or thick samples as melted glass, pellets, or as powders. The excitation of X-ray spectra can be performed by specific and polychromic radiation of X-ray tubes, by protons.deuterons d-particles and synchrotron radiation from accelerators and by o(-particles, X- and T-rays and by bremsstrahlung generated by p-particles form radionuclide sources. The most important advantages for the application of point or annular radionuclide sources is their small size, low weight, their longtime stability, and the versatility. Radionuclide sources are applied for the characterization of glasses, for the analysis of ceramics, dust, soil, ion exchanger materials, geological specimen, biological samples as dried and powdered grass, flours, milk, plant: ash, potatoes, and for the determination of heavy elements (mainly actinides as Th, U, Np, Pu, Am, Cm) in solutions from nuclear reprocessing plants. As standards for the analysis of solid samples powders have been used with silicagel, quartz, flour or mixtures of them as matrices. Small differences in density have been corrected by taking into account Compton scattering peak intensity. For calibration of liquids solutions containing TBP/octane,

HC1, HNCs, H,P0,, H-SO, or Al(N0o)3 have been measured.

- 204 - gogancs J.. Pinter T., Ifegy L.Gy."*, Vajda B1., Vodicska 3£ SolymoalJ. Paks Huclear Power Plant department of Applied Chemistry, Technical University of Budapest

RADI0A5ALYTICAL APPLICATION 0? ZIRCONIUM PHOSPHATES AT PAKS NUCLEAR POWER PLANT

While inorganic ion exchangers have been widely used in radioactive waste management of nuclear power plants based on the special selectivities differing from those of organic ion exchangers, less information have been accumulated about radioanalytical applications. Sose examples for chromatographic separations of the primary coolant by means of zirconium phosphates of different morphology will be presented. The common problem-of most of the radioanalytical methods used to determine the isotope composition of the primary coolant of \YWER type reactors is the necessity of the removal of matrix acitivities i.e. those of 42^ 24tfa and 18P. Zirconium phosphates are cation exchange, materials showing a definite tendency to retain fluoride anion thus assuring promising conditions for the selectiv separation of the matrix components. Radioiodine nuclides of the primary coolant regarded as indicators of the inhermeticity of the fuel cladding can- be continuously monitored in a by-pass branch due to the effective removal of all radioactive components except iodine by means of a column filled with amorphous zirconium phosphate. mission products /e.g. Cs,Rb,Sr,Ba,I/ can he analyse gamma-rspectrometrically following the chromatographic separation of primary coolant samples by means of amorphous zirconium phosphate.-The matrix activities are eluted with properly chosen acid and/or base. Due to the proper"enrichment the most important fission cations become detectable. Corrosion products can be selectively enriched and separated from the matrix .components passing the primary coolant sample through a column filled with crystalline c<-zirconium phosphate. Apart from primary coolant analytics zirconium phosphates can find application in environmental control of nuclear power plants. The radioactive concentration of ^fcs nuclide in surface waters and ash samples of different origin can be determined due to selective separation and enrichment by means of amorphous zirconiun phosphate. The separation processes applied to PAKS Nuclear Power Plant are either continuous, or automated batch-wis* ones. - 205 - 4. Radiopharmaceuticals and Radiolabelled

Compounds

- 206 - N.Vanlic-Razumenic, D-Veselinovic , and V.Nikolic Boris Kidric Institute of Nuclear Sciences, Vinca and Faculty of Sciences, Beograd, Yugoslavia

PHYSICO-CHEMICAL CHARACTERIZATION OF Tc-DFD COMPLEX - A BONE IMAGING AGENT. INVESTIGATION OF THE COMPLEX COMPOSITION A primary requirement in the rdtiondl design of Tc—radio­ pharmaceuticals is an understanding of the reduction and complexation processes of technetium. For that reason, prior to the preparation of ^c-DPD {2,J-^icarbexypro— pane-1,1-diphosphonate) skeletal imaging agent, the inter­ action of stannous ions, technetium-99 and DPD ligand was studied by use of the spectrophotometrie method. In our earlier studies, ve found out that DPD arid Tc reduced by bivalent tin formed colored complexes with 410 and 515 nm at a defined pH value of 3. The max r molar ratio Sn : Tc necessary for reduction was found to be 2.5:1 and 4.5:1. In order to determine the complex composition, the method of continuous variations was applied for reagent mixtures of DPD, Tc and Sn with fixed molar ratios Sn:Tc of 2.5:1 or 4.5:1. For both molar ratios of Sn:Tc, the complexes were foraed with reolar ratios of J?PD:Tc 1:1 arid 2:1. In both cases, a compound was also formed which-did not show absorption at the above mentioned wavelengths with molar ratio of DPD:Tc lower or equal to 2:3. In ad­ dition, another complex was found (polynuclear complex with DPD:Tc=3:2) in reaction mixtures with higher molar ratio of Sn:Tc (4.5:1). Furthermore, an interaction at both molar ratios of Sn:Tc was indicated by absorption at X. =410 nm, which c max most probably is not due to complex formation. This inter­ action was noticed at molar ratio DPD:Tc=4:l. Further investigations performed by use of the poten- tiometric titration of Tc + ligand by Sn(II) are in pro­ gress. 207 Soylu, A., Soylu, K., Aras, G., Srbay, G. Ankara University Medical School, Nuclear Medicine Dept. Ankara - Turkey

LABELING OF LEUKOCYTES WITH TECHNETIUM - 99m

Labeling of leukocytes using a simple and reliable method is of great importance in clinical nuclear medicine. In this study leukocytes are aseptically separated and labeled with Technetium - 99m. The labeled cells are used to show the abscesses and inflammatory reaction foci in patients. The separation has been achieved by dextran sedimentation method and leukocyte suspansions were examined by Giemsa and Trypan blue staining techniques. The number of erythrocytes were not more than 1-2 % and 85-90 % of the leukocytes were actively functioning. Labeling with Tc-99m has been performed in the presence of stannous pyrophosphate and labeling yield.was about 85-90 %. To prove that a good separation and labeling has been achieved, a few cases with known or suspected abscess have been studied and it was shown that labeled leukocytes lacalized at the inflammation focus.

- 208 - a.P. gate. M.J. Adam. J.X. Grierson. T.J. Xuta. W.H..W. Martin. J. Stoessl. and D.3. Calne. n.B.C./TRHJMF Program on Positron. Emission Tomography. University of British Columbia. Vancouver. B.C. VST 2S5. Canada.

THE SYNTHESIS OF PDSITHON-LABELLED RADIOPHASMACEuTICALS FOR THE STUDX OF MOVEMENT DISORDESS

Automatic or remote synthesis systems have been developed for the production of 18 18 11 F-2-fluoro-2-deoxy-D-glueose (2FDG). F-L-S-fluorodopa, C-carboxy-labelled L-dopa, and Br-bromospiperone. These compounds permit PET measurements on regional cerebral glucose metabolism, dopa metabolism and dopamine receptor density. The radionuclides have been produced with the TRIUMF CP42 cyclotron (1). A fully-automated microprocessor-controlled system effects the synthesis of 2FDG, via the reaction of gas-phase acetyl hypofluorite (2) with TAG in fraon. Monitoring information and remote manual intervention are available to the operator, and automatic synthesis is completed in 45 minutes from EOB. with a yield at EOS of about 201. The same microprocessor is used to control part of the synthesis of L-S-fluorodopa, via the reaction Of gas-phase acetyl hypafluorite with fully-protected derivatives of dopa (3). This synthesis takes 90 minutes from EOB with a yield of 8Z (at EOS) of L-6-tluorodopa after HPLC purification from the 2-isomer. C-carboxy-labelled L-dopa has been prepared by the Strecker method (4), applied for the first time to this compound. 3,4-dimathoxy-phenylacetaldehyde was reacted with ammonium carbonate, ammonium chloride and C-cyanide, followed by treatment with NaOH to convert the labelled hydantoin to the final product. HPLC with a chiral column (5) was used to separate the L-isomer which was concentrated via C-18 sep pak's, eluted with methanol, evaporated and heated with HI to remove the methoxy protecting groups. The final product in citrate buffer was obtained in a synthesis time of about 60 minutes with a radiochemical yield of about 31 fat ZJOS). 75 The synthesis of Br-bromospiperone was achieved by the method of Maziere et al (6), the direct labelling of spiperone with H 0 /HOAe-oxidised Br followed by HPLC 2 2 purfiuation. The synthesis time is about 1 hour with a radiochemical yield of >5QZ. These radiopharmaceuticals have been applied in studies of normal subjects and patients suffering from Parkinson's disease and dystonia. The data on L-6-fluorodopa uptake have been analysed via a model similar to that due to Fatlak and coworkers (7), while preliminary results on dapa-decarboxlation and receptor densities have been subjected to a more elementary treatment. Typical images and data obtained from specific cases are presented. 1) T. J. Ruth. Int. J. Appl. Rad. Isotop., _36_; 107-110(1985) 2) 0.1. Bid3 nfc al., J. Nucl. Med., 25, 1327-1334(1984) 3) M.J. Adam «t al., J.* Nucl. Mea. j26, P123U985) 4) L.C. Washburn et al., Radiopharm. II; Proe.of 2nd. Int.Symp.Radlopharm. ,757-777(1979). 5) J.R. Grierson et al., J. Chromatog., 325, 103-109(1985) 6) B. Maziere et al., (in press) 1985 7) C.S. Patlak et al., J.Cereb.Blood Flow Metabol.,_3, 1-7(1983).

- 209 - H- Maeda, S. Nishimura, T. Fukunura, and M. Kojima Faculty*cf Pharnaceutical Sciences, Kyushu University, Fukuoka 812, Japan

SYNTHESIS OF OPTICALLY ACTIVE. I C}PHEW"*LETHPROLAMINE USIisG 0XYNITF-ILASE-CP.TATY7FP aOHITTON HP HYDP^FN CYANIDE TO BENZALDEHYDE

Phenylethanolamine and octopamine are of growing interest as trace amines in the central nervous system. It is known that oxynitrilase-catalyzed additions of hydrogen cyanide to aldehydes occur with stereospecificity (1). This methodology has been exploited in the preparation of optically active C-11 labeled ethanolamines for biomedical studies with positron emission tomography.

No carrier added hydrogen [C-11]cyanide prepared by the N-14 (p,ci) C-11 reaction according to procedures described previously was treated with 50% sulfuric acid (2). The C-11 HCN was bubbled into a 0.3 ml-solution of 0.05 M 50% methanolic acetate buffer (pH=5.4) at -20 C. To this solution was added pure benzaldehyde (2 ug) and salt-free mandelonitrile lyase (EC 4.1.2.10, 4 units), and then stirred at room temperature for 7 min. After extracting with methylene chloride, the [C-11]-mandelonitrile obtained was reduced with. NaBH.-CoCl2 in methanol at room temperature for 10 min. The C-11 labeled phenylethanolamine hydrochloride was obtained os purification by cation exchange resin (AG50W-X12) in 7% radiochemical yield (not corrected for decay) from C-11 HCN in a synthesis time of 60 min. The optical purity of the R-[C-11]phenylethanol­ amine determined by conversion to the MTPA ester (3) and analysis of HPLC was 60% e.e. (R/S ='80/20). This work was supported in part by Takeda Science Foundation.

11 11 CN CH2NH2 HCI .»,9 c6HSCHO—f- * ^ H-C-OH —^4 ^ H-C-OH V ^6 5 -'™-' maodetonitrile < CoCI2 i lyase CgHs C6H5

1) W.Becker and E.Pfeil, J.Am.Chem.Soc., 8_8, 4299 (1966). 2) D.Van Haver et al., J.Labeled Compds.Radiopharm., 22, 657 (1985) . 3) J.A.Dale and H.S.Mosher, J.Am.Chem.Soc., 95, 512 (1973)

- 210 - Yao.F.2., Zhang,N.B., Ye.Y.F.. Lu,S.S., Lei.K.J., Xia.X.Q., Gan,Y.X., Sun ,J.F. Shanghai Institute of Nuclear Research, Academia Sinica, China

THE PREPARATION OF CARBON DISULFIDE (C3~S 5 AND ITS DERIVATIVES

35 C S is a key iiuermecate for preparing a variety 35 of S-labelled compounds. In this paper, a new method 35 for the synthesis of C 3_ is described. H? S is first obtained from a wet process reducing a KCl target after 35 being irradiated by thermal neutron, then, C S- is formed by passing H_ S through into a column of hot 35' charcoal. By this method, C S_ with an over-ail yield more than 90%, a specific activity of 36 mCi/mM with over 95% purity is obtained. For this radiochemical process, it is necessary that the reaction is carried out in a sealed tube. With an amount of 2-20mM, the procedure takes less than 24 hrs. KC1(35S0,) 1 4 H 35S 35„ 35„ 2 o JO, CH, || || r„ » J >N-C-S-S-C-t< 3 c"s2 ~Q>N •ONHCHNO CH. 35 35, CH, -NH- 35 CH. -NH 35

35 35 Moreover, phenyl ( S) isothiocyante, diphenyl ( S) thiourea, teramethyl ( S) thiuram disulfide, zinc ethylene ( S) biodithiocarbomate have been prepared 35 starting from the obtained C S_, and their yield , purity, specific activity are also satisfactory.

- 211 - S-K-Shuklaa* , C.Cipriani „ G.B.Manni „ A. Muller , L.OssiciniaJ, M.Cristallia) a)Istituto di Cromatografia, C.N.R., C.P. 10, 1-00016 Monterotondo Stazione(Roma);h)Servizio di Medicina Nucleare Ospedale S. Eugenio, 1-00144 Roma; c) Istituto Regina Elena, 1-00161 Roma, Italy A STUDY OF THE SOLUTION CHEMISTRY AND BIOLOGICAL BEHAVIOUR OF YTTRIUM-90 FOR MAKING IT LESION-SPECIFIC AFTER ITS ADMINISTRATION FOR NONINVASIVE MELANOMA THERAPY Melanoma is an aggressive disease for which no effective diagnostic and therapeutic agent was known(I). Even after surgical removal of primary melanoma, its metastases in in internal soft tissues continue to grow and spread leading to rapid death of the patient. We recently deve­ loped (2) gallium-67 formulation which contains the radio­ nuclide in chemical form with melanoma-specific affinity. In melanoma-bearing subjects the radionuclide gets firmly bound mainly in melanoma sits. With this formulation we are now carrying out noninvasive melanoma detection and follow-up studies. The object of our present study has been to find melanoma-specific yttrium-90 formulation for its use in noninvasive melanoma therapy because its nuclear properties are ideal for tumour therapy (3). The chemical form of yttrium-90 in different formulations was found by chromatography and electrophoresis. We could now obtain the radionuclide in the chemical form which is chromatographically and electrophoretically similar to that of melanoma-specific gallium-67. The biological be­ haviour of yttrium-90 was studied in Harding-Passey-, and B-16 melanoma-bearing mice. The whole-body radionuclide distribution was studied by radioactivity counting in weighed samples of organs and melanoma. Yttrium-90 in melanoma-specific formulation was found to concentrate mainly in the primary and secondary, melanoma. The radio­ activity in healthy organs was neglegible. Studies are now in progress to investigate the therapeutic action of our melanoma-specific yttrium-90 in Harding-Passey-,' and B-16 melanoma-bearing mice. These results will be presen­ ted and discussed. 1. S.M. Larson, J. Nucl. Med. 1985, 2_6, 538-545. 2. S.K. Shukla, C. Cipriani, G. Argird, I. Blotta", and G.B. Manni, "Melanoma Imaging with Ga-67 or with Labelled Antibodies", Proc. Int. Symp. RIA 85,p.27. 3. B.W.Wessels and R.D. Rogus, Med.Phys.1984,11,638-645. - 212 - Li 'Maoliangj Ku Kuaizhong, Song Dauhai and Wang Yiru Southwest Center For Reactor Engineering Research \nd Design, Chengdu, China A. tIEW STERILE In-113m GENERATOR

This paper describes a new method for preparing a new sterile mixed SnOp-ZrOp gel In-ll3rn generator with low specific activity Sn-113 produced by irradiating natural tin in reactor, on the basis of the special chemical behaviour of tin and zirconium. This method can be used for preparing In-113m generator of 50-100 mCi useful in nuclear medicine on request. In-113m of more than 60% can be eluted with 20 ml of 0.05 M KC1 solution, the ratio of Sn-113 and In-1l3m in eluate is less than 0.1%, and the concentration of zirconium in eluate is less than 20/xg/ml.

Comparing with the methods used before, this method has the following advantages; A. Low specific activity Sn-113 (about 50 mCi Sn-113/g Sn) can be used for preparing In-113m generator of up to 100 mCi with small column (less than 10 ml). B. without preparing hydrous zirconium oxide, the process is simplified, and a lot of zirconyl chloride can be saved.

C. More than SS% of Sn-113 can be mixed into Sn0_-Zr02 gel, and the radioactive liquid waste can be reduced to minimum. D. Low cost.

This new sterile In-113m generator is very useful in developing countries or in remote areas.

- 213 - Zhou, Y.G., Zhu, T., Zhao, H.Y., Wu, Z.M., and Tang, C. Shanghai Medical University, Shanghai, China

SYNTHESIS AND BIODISTRIBUTIONS OF HEPATOBILIARY IMAGING AGENTS Tc-99m(Sn)-PHT, -PHP, -PMT

Tc-99m(Siv)-N-pyridoxyltryptophan(OL, L)(PHT), -H-pyridoxyv-pheny^alanine (PHP), -N-pyridoxyl-5-methyltryptophan(PMT) have been synthesized. Pyridoxal was condensed with the postassium salts of the amino acid to give solutions of the Schiff bases. The Schiff bases were hydrogenated over a platinum catalyst or by an improved method of ours with sodium borohydride. The yields were: PHT(DL)69.0%,m.p. 233-234°C; PHT(L)76.8%, m.p. 241-242°C; PHP 64.0%,m.p. 233-234°C; PMT 85.8%, m.p. 234-235°C. . we have prepared lipid and lyophilized kits. The kits contained PMT(PHT, PHP) stannous chloride and Vit.C. The labelling efficiency was over 96%. TLC (MEK:MeOH:2M KCL; 10:9:1) showed the products having radiochemical purities: Tc-99m(Sn)-PHT(DL) Rf=0.68; -PHT(L); Rf=0.77; -PHP Rf=0.81; -PMT Rf=0.89. Rf values are different from those of free Tc-99m, Rf=0,94 and colloid Tc-99m, Rf=0. CVjnical radiochemical purity was evaluated by rapid TLC with two solvent systems (A. ethyl acetate: MEK: DMSO: water, 200:100:40:7; B. 85% MeOH). The results were obtained within 10 minutes. The influences of amount {PMT(PHT) Vit.C, stannous chloride) and pH on labelling efficiency were discussed. Compared with Tc-99m-PHT, -EHIDA. Tc-99m-PHT showed the most rapid l)lood clearance, the fastest hepatobiliary transit and the lowest urinary excretion in rats. Tc-99m-PMT had more resistance to serum bilirubin than Tc-99m- EHIDA in patients and was used in a bilirubin level of 28mg/dl. We have used Tc-99m-PMT in 40 patients for hepatobiliary imaging. The result is very good. Tc-99m-PMT can also be taken up by some hepatoma cells. In our io cases with histologically verified hepatocellular carcinoma, six cases showed concentration of Tc-99m-PMT.

- 214 - Liu.B.L., Meng,M.t Zhu.L., Jin.Y.T- & Kun^.H-F-* Department of Chemistry, Beijing Normal University •Department of Nuclear Medicine, SUNY/Buffalo.

SYNTHESIS AND BIODISTRIBUTION OF In-113m-BAT-TE AS A NEW MYOCARDIAL IMAGING AfiKNT.

The use of 3,3,10,10-tetraethyl-l,2-dithio-5,8-diazacyclodecanehydro- chloride(BAT-TE) as a new ligand for the preparation of In-113m-BAT- TE was investigated. The chelating reaction of BAT-TE with In-113m, by mixing ll3BIiaCL3 and BAT-TE in pH 5 buffer and heating at 80°C for 5 min, gave a labeling yield of 98*. The simple and- rapid synthetic technique employed in the prepartion of In-113ra-BAT-TE would be suitable for In-113m, which has a short physical half-life (99.5 rain).

/V_/VH

The biodistribution of In-113m-BAT-TE in mice exhibited high myocardial uptake and selectivity. The radioactivity in the heart also showed very slow wash-out and high heart to blood (H:B) ratios during the time period Tram 5 min to uC min. The results of biodistribution of In-113m-BAT-TE are shown as follows:

Mean percent dose per gram + SD (5 mice)

Organ time 5 min 15 min 30 min 60 min heart 32 14+5.62 22.82+5.69 18.04+2.48 10.13+2.26 blood 2. 33+0.27 1.39+0.20 1.02+0.17 0.81+0.23 lung 27 21+6.05 12.30+5.20 8.48+2.98 5.82+1.20 liver 12. 13+2.21 7.18+1.50 6.03+1.99 3.97+0.26 H/blood 13.85 18.57 15.73 12.13 H/lung 1.00 1.98 2.05 1.72 H/liver 2.80 3.36 2.91 2.43

Based on these experimental results, In-113m-BAT-TE shows promise as a possible radiotracer for myocardial imaging.

- 215 - J.V. Evans Australian Atomic Energy Commission, Research Establishment, Private Mail Bag., Sutherland, NSW 2232, Australia

TECHNETHJM-99m GENERATION USING AN INORGANIC GEL

A new concept for a molybdenum-99/technetiutn-99m generator based on a zirconium molybdate gel is being developed/1). The generator uses an insoluble gel which has an open structure allowing free diffusion of Che pertechnetate ion and hence recovery ot technetium-*)*)™ in high yield by a simple elution technique. The gel contains approximately 250 mg g a of molybdenum allowing the use of the lower specific activity reactor-irradiated molybdenum—99 rather than the more common fission-product molybdenum-99. The advantages of the concept include avoiding the high cost ot processing irradiated uranium and problems of fission—product disposal, the freedom from organics in the process and simplicity of generator operation. (2) The viability of the concept has been demonstrated by the preparation and daily elution over fourteen days of generators with activities up to 2 TBq. Elution efficiencies we*e usually better than 80%, and molybdenum, zirconium and radionuclide impurities were less than the limits set by British Pharmacopoeia. The biodistribution of radiopharmaceuticals prepared with pertechnetate from gel generators did not differ significantly from thosj-prepared using the product from commercial chromatographic generators. The gel is an amorphous glassy solid with a stoicheometry approximating to a ZrO2.MoO3.xH2O. Investigations of the chemical factors controlling the performance of the gel in respect of chemical stability and elution efficiency showed that two features of gel chemistry were of particular iteporcance.

Molybdate species present in the solution used to precipitate the gel appear to be retained in the final gel structure and are a critical factor in determining the stability and, elution characteristics of the gel. Optimum gel properties were obtained from molybdate solutions in which the predominant species are hepta and octa polymolybdates.

A proportion of anion exchange sites are retained in the predominantly cation exchange gel. The rate of elution of Tc0i» was found to be surface controlled by virtue of the density of these sites which are associated with the zirconium hydrous oxide structure retained in the gel.

1. Evans, J.V. and Shying, M.E. [1984] Report AAEC/E599. 2. Moore, P.W., Shying, M.E., Sodeau, J.M., Evans, J.V., Maddalena, D.J. and Farrington, K.H. [1986], Int. J. of Appl. Rad. & Isotopes, in press.

- 216 - R.D. Finn*, S. Wukovnig, T. Soothe, M. Vora, and a.J. Ache** *NatJonal Institutes of Health, Clinical Center, Department of" Afaclear Medicine, Bethesda, MD.; Cyclotron Facility, Mount Sinai atedicai iCsnteir, MJ.

CYCLOTRON PREPARATION OF "NO CARRIER ADDED" GADOLINIUM-153 DTPA RADIOPHARMACEUTICAL

Paramagnetic compounds, such as complexes of gadolinium, have been shown to selectively enhance the relaxation rate of water protons in vivo. Readily apparent is the application of these various compounds as enhancement agents to the rapidly devel­ oping field of medical resonance imaging (1-3).

However, in order to evaluate the pharmacokinetics and bio­ logical distribution of the diethylenetriaminepentaacetate com­ plex of gadolinium (Gd-DTPA), an analytical procedure^ was devel­ oped to prepare and separate "no carrier added" gadolinium-153 produced via the Irradiation of natural gadolinium targets with energetic protons. A two-step separation procedure employing AG 50 cationic exchange resin with 2-hydroxyisobutyric acid/sodium hydroxide as the solvent resulted in the separation of the radionuclides from the gadolinium target matrix. Following a suitable decay period, the gadolinium-153 radionuclide was eluted.

The results of our experiments monitoring cyclotron producrion of terbium and gadolinium radionuclides, distribution coeffici­ ents, preparation of radiopharmaceutical and its detection using high pressure liquid chromatography will be presented.

ACKNOWLEDGEMENT We gratefully acknowledge Schering AG (Germany) for providing the authentic sample of Gd-DTPA disodium salt.

References

1. H.-J. Weinmann, R.C. Brach, W.-R. Press, and G.E. Wesbey, Ameri. J. Roent., 142, 619 (1984).

2. H.-J. Weinmann, M. Laniado, and W. Mutzell, Physiol. Chem. Phys. Med. NMR, 16_, 167 (1984).

3. D.H. Carr, J. Brown, G.M. Bydder, H.-J. Weinmann, U. Speck, D.J. Thomas, and I.R. Young, Lancet, 48 (1984).

- 217 - KABALKA, G. W.** and BIERER D. E.* Department of Chemistry and Department of Radiology"*, University of Tennessee, Rnoxvilli Tennessee 37996-1600 U.S.A.

SYNTHESIS OF 123I-I0D0VINYLAMIN0 ACIDS VIA ORGANOB0RANES: POTENTIAL TUMOR-IMAGING AGENTS-

Radiolabeled vinyl iodides, first reported in 1981 CO have proven to be an effective means of stabilizing radioiodine in-viyo. The direct reaction of vinyl- boronic acids with labeled sodium iodide provides an efficient method for producing no-carrier-added vinyl iodides(2).

Nal23 ,B(OH)? i 10] * We wish to report that the method can be used to prepare variety of iodovinylamino acids. Unnatural amino acids accumulate rapidly in tumor tissue but the amino acids investigated to date have been labeled with carbon isotopes(3,4) which are not always readily available. The accessibility of the new iodovinylamino acids may prove valuable in nuclear medicine investigations focused on tumor detection. J "* )siH I- Na^n/[0] *"* (Ho),B^^r~i TT^^l -™^M^>v- O

This research was supported by a grant from the office of Health and Environmental Research, U. S. Department of Energy. (1) Kabalka, G. W.; Gooch, E. E.; Sastry, K. A. R.; J. Nucl. Med., 2_2, 908 (1981). (2) Kabalka, G. W.; Ace. Chem. Res., 17, 215 (1984). (3) Hubner, K. F.; Kraus, S.; Washburn, L. C; Gibbs, W. D.; and Holloway, E. C.; Clin. Nucl. Med., 6, 249 (1981). ~ (4) Buonocore, E.; Hubner, K. F.; Collmann, I. R.; J. Comp. Assist. Tom. , 3_, 825 (1979). ~~ - 218 - .Js'un, S.Y. , Liang, G.L. , Li, B.A. , and Lin, J.F. Department of Isotopes, Institute of Atomic Energy, Beijing,, China

AM INVESTIGATION ON THE SEPARATION OF HIGH SPECIFIC ACTIVITY Mo-99 FOR MEDICAL USE FROM FISSION.PRODUCTS OF U-235 BY MEANS OF COLUMN CHROMATOGRAPHY

The chroma tographic extraction behavior of several organophosphorous extractants for Mo-99 as well as some significant fission products was investigated. Based on the results obtained above, an extraction chromatographic process for separating Mo-99(f.p) was developed. The stationary phase is HDEHP on resin and the mobile phases are HNO3 with or without reducing agents. Experiments show that the proposed method produces Mo-99 with a radionuclidic purity of more than 99.9Z and a recovery efficiency of approximately 92%. Studies related to the separation process, such as radiation degradation of the stationary phase on different supports, are also described.

In addition, a new procedure for the production of multicurie high quality Mo-99(f.p) by means of high performance inorganic chromatography has been developed which is characterizd by the use of ordinary fuel elements (enrichment of U-235 102) as target, separation of high purity Mo-99 from fission products by only a single efficient column without any purification step, and radioactive solid and liquid wastes reduced to a minimum. The procedure is being successfully used to produce multicurie Mo-99(f.p) satisfactory for manufacturing high quality Tc-99m generator.

- 219 - Brian F. Abeysekera Atonic Energy of Canada Limited, 4004 Wesbrook Mall, Vancouver. B.C. V6T 2A3

1-123 LABELLED RADIOPHAKMACEOTTCMS

The development of 1-123 labelled radiopharmaceuticals has been hindered by the absence of a regular supply of high purity 1-123. Recently, AECL developed a process in which JCe-124 gas was irradiated at 24-30 KeV in a CP-42 cyclotron to produce ultra-pure 1-123 [ > 99.9*) by a p,2n reaction. This material not only gives better image quality but reduces, excessii-c patient exposure to radionuclidic iispurities, especially 1-125. AECL 1-123 has been very successfully incorporated into a large variety of pharmaceuticals. 123 A radioiodirtated fatty acid analocue, para- iodophenylpentadecanoic acid (IP?A) h£s shown graat promise for the non-invasive detection of myocardial injury in human patients. AECL has developed a viable commercial scale synthesis of this pharmaceutical by radioiodinating an organothallium intermediate. The product is isolated and purified by HPLC In,.an S5% overall yield. This method has produced up to 750mCi of material. Iodine labelled Hippuran has been used for renal imaging since 1950. The' isotope most commonly used has been 1-131 but the most suitable isotope for imaging is 1-3 23. AECL now routinely produces up to 500mCi of 1-123 Hippuran, made by exchange labelling. Over 99% of the label is incorporated into the substrate.

Estradiol derivatives have been used with modest success to locate and identify in vivo, estrogen receptor .positive tissues. Estradiol 17 B labelled in the 16 a position has been shown to be quite effective in binding to receptor sites. A drawback so far has been the lack of a rapid synthesis, with published methods of 1-123 for Br exchange taking over 24 hours to obtain an appreciable yield. AECL has developed a synthesis that can be finished in 40 minutes with a yield > 50%.

AECL 1-123 had also been used to label HIPDM, IMP, MIBG and a variety of proteins and monoclonals.

1.P.V.Kulkarni, P.L.Kennedy, J.T. Willerson. D.E. Jansen, G. Gabliani, C. Morgan, W.D. Brown, R.W. Parkey and J.R. Cobett, J.Nucl.Med., 26, p88 (1985). 2. M. Tubis, E. Posnick and R.A. Nordyke, Proc.Soc.Exper.Biol. (N.Y.) Vol 103, 497-498 (1960). 3. E.M. Jagoda, R.E. Gibson, H. Goodgold, N. Ferreira, B.E. Francis, R.C. Reba, W.J. Rzeszotarski and W.C. Eckelraan, J.Nucl.Med., 25, 472-477 (1984). 4. R.B. Hochberg, Can.Pat. 1178885 (1984).

- 22C - H. Korpela, J. ftaltonen , J. Keiuouen and A-L- Kairento Helsinki University Central Hospital, Accelerator Laboratory and ^Department of Radioctaemlstry,, University of Helsinki,Beislinki, Finland

PREPARATION OF 2-18F-FLU0RO-2-DE0XY-D-GLUC0SE BY NUCLEOPHILIC SUBSTITUTION WITH TANDEM ACCELERATOR PRODUCED 18F-FLU0RIDE

An effective water target with a volume of 0.7 ml was used for the production of '8F-fluoride (1). After 60 minutes1 irradiation of •°0-enriched water (98 %) with a 9-5 MeV proton beam from a EPG-10-II tandem accelerator using; a bean, current ef 5--4 &aA, l^F-activity up to 180 mCi was obtained.

A remote controlled apparatus (2) was constructed for the production of 2-18F-fluoro-2-deoxv-D-glucose C2-18F-FDG). The synthesis was based on the method described by Tewson (3). Activated water was introduced into flask containing 7.26 mg of tetramethylamraonium hydroxide and 3.7 mg of tetramethylamraoniuia fluoride and evaporated to dryness at 130 C. The white residue was dried by addition and intermittant evaporation of three 5 ml aliquots of dry acetonitrile and 13.78 mg of 4,6-benzylidene-1-B-niethyl-D-mannopyranoside-2,3- cyclic sulphate in 10 ml of dry acetonitrile was added. The solution was heated for 12 rain at 80 C and the solvent evaporated. The protective groups were removed by treatment with 5 ml of 1 mol/1 boron tris(trifluoroacetate) in trifluoroacetic acid for 15 min at 55 C, after which 2 ml of water was added, the reaction continued for 2 min and the solvents evaporated. Borate was removed by the addition and evaporation of two 5 ml aliquots of methanol followed by one aliquot of water (*•). The residue was dissolved in 5 ml of water. Fluoride as well as coloured impurities were removed by passage through a neutral alumina column (0.9 x 10 cm) using water as eluent. 2-18F-FDG-containing fractions were used in experiments with human tumor implanted nude mice.

The overall yield ranged from 15-40 %, with a synthesis time of about 90 min. 2-18F-FDG was the main product as analysed by TLC (silica gel, acetonitrile/water 95:5; n-butanol/acetic acid/water 15:7:8; methanol/chloroform/acetic acid 15:85:1) and autoradiography, although several labelled impurities were also present. When radio­ chemical purity was determined by HPLC, using NH^-column with 70 % acetonitrile as eluent, no impurities were observed. There appears to be a poor correlation between TLC and HPLC results, which emphasized..-the need for careful checking of radiochemical purity.

1) Keinonen, J. et al.f Int.J.Appl.Radiat.Isot. (submitted, 1986) 2) Ginos, J., (personal communication, 1985) 3) Tewson, T., J.Nucl.Med. 24 (1983) 718 M Hutchins, L. et al., Int.J.Appl.Radiat.Isot. 36 (1985) 375 - 221 - C.-Y. Shiue, L.-4Q. Bai, R. Teng and A. P. Wolf Cheaistry Departneat Broofchaven National Laboratory, Upton, NY 11973 USA

APPLICATION OF THE NUCLEOPHILIC FLUORINATION REACTIONS TO THE SYNTHESIS OF NO-CARRIER-ADDED (NCA) 18F-LABET,ED RADIOLIGANDS

Recently, we reported a general synthetic strategy for the prepar­ ation of a series of NCA 18F-labeled butyrophenones1'^ using the nucleophilic aromatic substitution reaction. Based on studies in animals4*5, we found that [l8F]N-methy^Lspiroperidol ([1SF]NMS) is an ideal radioligand for studying the dopamine receptor In human. However, the synthesis of ['•°FJNMS is multistep. We report here the application of nucleophilic aliphatic substitution reactions to the synthesis of [*8F]NMS analogs and other receptor radioligands for PET studies. Reactions of compound la-d with K[18F]/Kryptofix 2.2.26 In MeCN at 65-75°C for 10 min followed by purification gave the corresponding NCA [18F]fluoroalkyl halides (2a-d) in 30-40% yield.

• 0

(CH2)nX2 ^18F(CH2)nX ^ ^-b-N-(CH2)n13F

a) n=2, X=Br; b) n=2, X-I; c) n=3, X=Br; d) n=3, X=I.

N-Alkylations of amides and/or secondary amines with 2 gave a 18 18 serieries of NCA N-[i0F]fluoroalkyl radioligands {3)Q) (N_-(2-[1<5F]F]f luoro- ethyl)spiroperidol, N-(3-[18F]fluoropropyl)spiroperidol, £-(3-[l8F]- fluoropropyl)normetazocine and N-(3-[18F]fluoropropyl)lorazepam) in 20-60% yield. The application of this method for the syntheses of other radioligands for PET studies in continuing. Research supported by the U. S. Department of Energy and its Office of Health and Environmental Research.

1. C.-Y. Shiue, J. S. Fowler, A. P. Wolf, M. Watanabe and C. D. Arnett, J. Nucl. Med. 26_, 181-186 (1985). 2. C.-Y. Shiue, J. S. Fowler, A. P. Wolf, D. W. McPher.son, C. D. Arnett and L. Zecca, J. Nucl. Med. 27, 226-234 (1986). 3. F. Cacace, M. Speranza, A. P. Wolf and J. S. Fowler, J. Label. Cmpds. Radiopharm. 18, 1721-1730 (1980). 4. C. D. Arnett, C.-Y. Shiue, A. P. Wolf, J. S. Fowler, J. Logan and M. Watanabe, J. Neurochem. 44, 835-844 (1985). 5. C. D. Arnett, J. S. Fowler, A. P. Wolf, C.-Y. Shiue and D. W. McPherson, Life Scl, 36_, 1359-1366 (1985). 6. K. .Hamacher, H. H." Coenen and G. Stocklin, J. Nucl. Med. 27, 235-238 (1986). - 222 - Zhou, Y.G., Zhu, T., Zhao, H.Y., Wang, L.M., and Shi, Q.X. Shanghai Medical University Shanghai, China

AN IMPROVED SYNTHESIS OF A BONE IMAGING AGENT Tc-99m-HMDT AND ITS BIODISTRIBUTIONS

Tc-99m-Hydroxymethylene sodium diphosphonate[Tc-99m-HMDP] was reported to be a superior bone imaging agent. It was found to have higher bone affinity, lower blood and soft tissue backgrounds in primary and metastatic bone tumors. We have improved the sythesis method: the tetrachloroethane pyrolysis was changed into hydrochloric acid hydrolysfs; high prossure catalytic hydrogenation was turned into room temperature and atmospheric reduction with sodium borohydride. Thus we simplify the synthesis, reduce the time for reaction and raise the yield. We have prepared vials containing a lyophilized sterile, pyrogen-free mixture of HMDP 2mg, stannous chloride 0.16mg, and Vit.C 0.5mg. The pH was adjusted to 6.0-6.2. The addition of sodium pertechnetate Tc-99m produced a rapid labelling of 95*. Radiochemical purity was shown with TLC [A. MeOH 85£ B. SALINE].

The biodistribution studies in rats revealed that relative bone concentration was in the order of Tc-99m-HMDP > -MOP > -PYP. The soft tissue concentration was also found in the order of Tc-99m-HMDP< -MDP < -PYP. The Tc-99m-HMDP Bone/soft tissue ratio was 311, but Tc-99m-MDP Bone/soft tissue ratio was 113.

We have used Tc-99m-HMDP in 22 patients for whole body bone imaging.

We can obtain clear image 3hr. after injection.

- 223 - Jin.YTT., Liu B.L. & Rung, H.F-* department of Chemistry, Beijing Normal University *Depnrtwent of Nuclear Medicine, SITNY/Buffalo

PRELIMINARY STUDY OK PREPARATION AND ANIMAL DISTRIBUTION OF "»Tcz(CO)ia AS A NEW BRAIN IMAGING AGENT. Recently, interest in the development of various technetium chelates for brain imaging has increased. Several ligands, such as BAT (or DADS) and PnAO, have been synthesized. When chelated with the reduced Tc-99m, they show ability to cross the blood-brain- barrier(BBB). A new type neutral and lipid-soluble of Tc-99m complex, 99mTca(CO)io, based on carbon monoxide ligand was studied.

The reported method for "Tc2(CO)io preparation, 200°C and 220 atm of carbon monoxide, was not very practical for routine nuclear medicine use. A more simpler method for carbon monoxide complex formation, using formic acid and sulfuric acid to generate carbon monoxide in situ for reducing 99lBTc04- and complex formation was developed. The biodistribution studies of 99oTc2(C0)ia in mice have demonstrated that it crosses the BBB, with 2.0% and 1.-68X of the injected dose per gram of brain tissue at 2 min and 15 min post intravenous injection, respectively. At 30 min, the brain uptake remains high at LOSS; dose/gram. The brain uptake in mice was significantly higher than those for """Ted".

brain uptake X/g 2 min 15 min 30 min "«Tc2(CO)io 2.02 1.68 1.08 99m Tc04- 0.18 0.19 0.18

This preliminary study suggests that "°Tc2(CO)io may be useful as a new brain imaging agent.

- 224 - Liu.B.L..Wang.X.B..Tang.Z.G-.Liu.X.J*.Shi.R.Ft, Guo.X.Z* & Xia.Z.M.# Beijing Normal Univ.,* Fuwai Hospital of the Chinese Acaceny of Med.Sci.,# Institute for Drug and Biological Products control of the Health Ministry

THE STUDIES ON KINETICS OF LIGAND EXCHANGE REACTION BETWEEN Tc-99m-GLUCOHEPTONATE AND t-BUTYLISONITRILE

The cat ionic complex Tc-99m hexakis(t-butylisonitrile)- technetium(I)[Tc-99m-TBI] has been shown to concentrate in myocardial tissue of several animal species.The com­ plex Tc-99m-TBI was synthesized and Kit of TBI was pre­ pared in China.Images of excellent technical quality were obtained from more than one hundred subjects and Patients.Preliminary work has demonstrated that Tc-99m- TBI is a valuable myocardial imaging agent for myocar­ dial ischemia and infarction.

-Tc-99m-TBI was prepared by ligand exchange reaction between Tc-99m-GH and TBI.The radiochemical impurities were less than 4 % in all cases.

-The ligand exchange reactions were studied at different pH values.temperature,time and calcium glucoheptonate concentration.The exchange yield was determined by paper chromatography and reaction rate constants were calculated at differnt pH values.

—From our results,we conclude that the ligand exchange between Tc-99m-GH and TBI is a second order reaction. In above cases,the rate constant of the ligand exchange reaction can be expressed x [Tc-GH]o K= rTRT i r—In or 1 .i-^Jo' - [Tc-GH]0-[Tc-TBI]t 1 Kt= ln(F0/Ft) [TBI]0

Hence,plots of ln(F0/Ft) vs. time of reaction are linear. The exchange reaction constants were calculated from the slop of above equation.The rate constant of the li­ gand exchange reaction is influenced by various pH va­ lues .

- 225 - Lu, J.X., Yang, L.P. Institute of Nuclear Research,Academia Sinica, Shanghai, China

RADIOPOLAROGRAPHIC DETERMINATION OF 12^I" IN Na123I

in using radionuclide -^1 for diagnosis and therapy of thyroid disease.lt is necessary to determine the radio­ active concentration and radiochemical purity of ^I~. The radiopolarographic method can determine not only 12^5 - radioactive concentration of ^1 ,but also- its radioche­ mical purity.Ordinary electrophoretic and chromatographic analysis can only estimate radiochemical purity. Procedure:radio-iodide solution containing 0.1M KNO, as supporting electrolyte is added to chloroform liquid layer,and the D.M.E. and S.C.E. is dipped into the solu­ tion. Then, mercury drop is collected in the potential range -0.6 — +0.IV,and counted radioactivity of treated mercury drops to obtain radiopolarogram.Radioactive can­ 't 2^ - centration of -'I is determined from the standard cur- ve,and radiochemical purity of ^1 is calculated from its ratio to total radioactivity of the solution. The relationship between radioactive concentration of

DYNAMICS OF DEUTERIUM DISTRIBUTION IN HUyANS 2 USLNiG ,0(-Y,n) TACTION.

A rapid non-destructive and sensitive technique is used by which total body water and its race of turnover (excretion) in humans can be easily measured. Subsequently, a simple calculation is made in estimating the total body fat and lean body mass. These measurements are, therefore, expected to shed a useful light on a measurement technique as well as on the movement of body water in humans, and this will glean an understanding of physiological laws governing such movements. The method employs the activat­ ion of deuteron in water by bremsstrahlung radiations which are produced by stopping 3 MeV electrons in gold target. The detect- 2 ion of photo-neutrons, so obtained in the reaction D(y,n) , is accomplished by the capture of fission fragments in Solid State 235 Nuclear Track Detector (SSNTD) iss\iing from the U(n,f) re­ action. These fission events are then automatically counted by a Spark Counter. Thermal neutrons, required for the U-235 fissioning, are obtained by employing a graphic moderator assem­ bly at the core of which water and urine samples are being irradiated.

Developments of a few basic measurement parameters and their utilisation in such measurements are also reported in the paper. - 227 - Shen, D. C.» Ji, L. Z.„- Liao, S. Institute of Atomic Energy, Beijing, China

SYNTHESIS OF TRIT .: LABELLED NUCLEOSIDE TRIPHOSPHATES BY ENZYMATIC P1 -3fHORYIATION

3 Tritium labelled nucleoside monophosphates: (5- H)UMP, (5-3H)CMP, (8-3H)AMP, and (8-3H)GMP were prepared from the homologous bromides; 5-BrUMP, 5-BrCMP, 8-BrAMP, and 8-BrGMP bj catalytic halogen-tritium replacement. 3 Tritium labelled nucleoside triphosphates: (5- H)UTP, (5-3H)CTP, (8-3H)ATP, and (8-3H)GTP were subsequently synthesized from (5-3H)UMP, (5-3H)CMP, (8-3H)AMP, and 3 (8- H)CMP through enzymatic phosohorylation with the crude enzyme extracted from brewer's yeasts.

An improved tritlation apparatus which involves some tri- tiation reaction flasks was designed for the preparation of four kinds of tritium labelled nucleoside ssaophas- phates at the same time.

The crude enzyme exti^cted was suitable for the synthesis of four kinds of tritium labelled nucleoside triphos­ phates. The conditions of different enzymatic reaction for each tritiated nucleoside monophosphate were studied. The yield of tritium labelled nucleoside triphosphate was more than 70Z, la addition, tritium labelled nucleoside monophosphates and diphosphates were obtained, namely, twelve kinds of tritium labelled compounds with high specific activity were synthesized by this new technique and purified by pape_r chromatography. The specific activities of these products were between 14-19 Ci/mM and their radiochemical purity, more than 98Z. x

- 228 - Institute of Atomic Energy, Beijing, China

STUDY ON SODIUM O-IODOHIPPURATE AND S0D1UH O-IODOHIPPURATE C131I) BY HPLC

In this paper, a HP1X is described to be applied to analyse a content: of o—iodobenzoic acid in sodium o—iodohippurace material and Co study radiochemical purity and chemical purity of sodium o—iodo— nippurate ( I).

A mobile phase presented in this method is : 1 m mol (NH.) H_PO,: CH-OH (25:3 v/v) PU7. This method is rapid, simple and gives accurate results for determination of o—iodobenzoic acid content.

Radioactive reversed-phase HPI.C is developed further in this paper. It is suited to study radiochemical purity and chemical purity of 131 sodium o-iodohippurate ( I). Its separation time is 7 min. The reservation time of impurity I and o-iodobenzoic acid ( I) is 2.4 min and 4 min, respectively. The reservation time of sodium 131 o-iodohippurate ( I) is 5.8 win. The method has the advantages of rapidity, sensitivity and exactness in compare with -Che paper chromatography.

Finally, the reason for the ejrror, which appeared in ordinary paper chromatography with benzene-ice acetic acid-water system as solvent for sodium o—iodoh ippurate, is disscused.

- 229 - Xue Jiayu and Li Yoner.jian Shanghai Institute of Nuclear Research, Acadsmia Sinica, P.O. Box 320^, Shanghai, China

THE PREPARATION AND APPLICATION OF AN IODINATION AGENT FOR RADIOPHARMACEUTICAL SYNTHESIS

The newly emerged solid phase oxidant 1,3i4,6-tetra- chloro-3c«.» 6c*-diphenylglycoluril (chloroglycoluril) h'as shoaeed sccte promising features for iodizing bio- active proteins. Although chloroglycoluril product is commercially available ( inder the trade name Iodogen), the results of its applications sometimes diversed considerably. This paper describes the preparation, analysis, and identification of pur^e chloroglycoluril for evaluation of its merits in radioiodination of protein. The human fibrinogen (hFbg) was employed as a model protein to investigate the applicability of chloroglycoluril towards radioiodination bioactive material. This was compared with conventional chloramine-T. The increasing of either chloroglycoluril or reaction time enhanced the labelling rate and reached constant at about 73# bat caused no influence on clottability (remained over 90,3). The mode of using chloroglycol­ uril film was better than suspension in labelling rate but no difference in clottability. This iodination system withstood dilution of reaction volume to 50 folds without any change on both labelling rate and clottabi­ lity. In contrast the labelling by chloramine-T had labelling rate around 62Ja and clottability less than 80^. The chloroglycoluril radioiodination was proved to be a mild, efficient, simple, rapid and less restric­ tive method specially suitable for labelling bioactive materials. - 230 - Zhang Xin, Bao Yue-wen, Ding Hu-qin

Shanghai lastitate of Materia. Hedica, Academia Sinica,

Shanghai, China.

SYNTHESIS OF 3H AND X C IA32L5D CHANGROLIN

Changrolin developed in our institute is a novel antiarrhythmic agent. For pharmacological studies radiolabeled changrolin is required. In this work specifically labeled changrotin (l, II, III) were prepared. /—-J* J j—»| I (o-^H)-changrolin

The synthetic route of I is illustrated in scheme 1. Heating jj-bromoanthranilic acid with formamide yield IV, which on heating with ?OCl_ gave Vr condensation of V with ^-aminophenol and then subjected to Mannich reaction afforded 6-bromochangrolin (VI), catalytic dehalogenation of VI with tritium gas gave I. For the synthesis of II ( C)-formamide and anthranilic acid were used as starting materials, the labeled chloro^uinaaoiin obtained was condensed with Mannich base (VIl) directly (scheme Z). Ill was prepared as the last step of scheme 1 using ( G)-formaldehyde. Preliminary pharmacological examination of I and III has been carried .out. scheme 1 NH OH

"©C^ N IV HCHCHO I HNQ schema 2 Gl VI, III R= 3r, H II

- 231 - Li, Z. >1. , Xia, Z. P. Institute of Atomic Energy, Beijing, China

PHIMARY STUDY ON THE MECHANISM OF TRITIUM LABELING BY MICROWAVE DISCHARGE METHOD

A method of labeling by rjJicrovave discharge is described vhic.'i is applicable to a broad range of organic com­ pounds. The method is rapid, inexpensive, and nondes­ tructive, thereby making the purification of labeled material relatively uncomplicated. The labeling reaction is initiated by ssicrowave discharge activation of the tritium gas and the samples of LRH-A, 5-HTP, and 5-FU are put on different reaction containers which are made of aluminium, hard glass and silicone.

The results of the labeling experiments indicate that the specific activity of the labeled compounds is dif­ ferent on the different reaction containers. The indi­ rect evidence suggests a free radical mechanism invol­ ving tritium atoms. A possible reaction mechanism, con­ sistent with our data is proposed as follows:

3H + R.H = R. + 3HH (1)

3H + R.H = R3H + H (2)

3H + R. = R3H (3) The tritiun atons formed in the snicrovave discharge would be the major species reaching the target area, but the apparent tritium atom concentration could be changed with different reaction container surface on which the tritium atoms could be recombined into molecu.1- es. For recombination, three body collisions, T+T+M, are necessary and take place in part on surface. The fraction cf collisions which lead to recombination on aluminium _2 walls has been measured as 10 and this is reduced to -A -5 10 and 10 on hard glass and silicone walls respec­ tively. It is evident that the specific activity of the labeled compound, obtained on container with lower value of recombination chance should be higher..This has agreed well with our experimental results.

- 232 - Cag,G.Y. .Chi.L.Y. ,Huo.Z.C. .Re.H.N.. , and Dong, Y.C.

Institute for Application of Atomic Energy. CAAS.

Beijing. China

PREPARATION OF TQREE KINDS OF PESTICIDES LABELLED

•WITH C-14 OB S-35

The fungicide l-{4-chloro-phenoxy-)3,3-dimethyl-l(l-H

1.2,4-triazol-lyl-)2-butanone(Friadimefon) was labelled

with C-14 ire triasole gromp. The synthesis was

accomplished in three s-teps starting with aminoguanidine

bicarbenate and formic acid C-14.

The insecticide o,o-dimethyl-o-(2-methylcarbamoyl-l-

methyl-vinyl) phosphate(Azodrin) was synthesized with

C-14 label in methoxy group. The modification was

carried out on the exchange reaction between methanol

C-14 and trimethyl phosphite.

The fungicide tetramethylthiuramdisulpuide(Thiram) was

labelled with S-35 by isotope exchange reaction between

element S-35 and Thiram instead -of synthesis.

The radiochemical yields of Friadimefon C-14 , Azodcin

C-14 and Thiram S-35 were 26%(from formic acid C-14),

42,4£(from Ba*CO,) and 47.3% respectively. The

radiochemical purities were all more than-95%.

- 233 - Gu, M.Y., Zhang, X.W., Tian, S.H. Institute of Radiation Medicine,

Chinese Academy of Medical ScienceT Tianjin, China

SYNTHESIS OF [3-UC] INDIRUBIN

It has been demonstrated that indirubin has significant effect on treatment of chromic granulocytic leukemia. For extensive study of its me Cabal is:a and its action mechanism [3- C] indirubin is synthesized.

The synthesis started from [^CjKCN, which was reacted with N,N'-diphenylthiourea in the presence of basic lead carbonate to give N,N'-diphenylt^^C]-cyanoformamidine(l). subsequent cyclization of (1) in the presence of anhydrous aluminium trichloride and then hydrolysis with 5£ hydrochloric acid at S0-90°C [3-14C]isatin(ll) was obtained. Condensation of (11) with excess potassium 3-indololate under a nitrogen atmosphere in basic solution at 70°C afforded the title compound(111). The product was further purified by silica gel column chromatography followed by washing with dry ethyl other to give a radiochromatography pure [3-^4C] indirubin(111), in an overall, radiochemical yield of 20.34Z (53.83mCi/m mol) from [^4C]KCN a radiochemical purity of 99-9% was checked by thin layer chromatography on silica gel G in three solvent systems.

- 234 - it * Y. Mirtai, M. K. Kubo, S. Aabe, T. Nosaki, and T. Toainaga Department of Chemistry, Faculty of Science, The University of Tokyo, Hongo, Tokyo, JAPAN. Institute of Physical and Chemical Research, Wako, Saitama, JAPAN. CYCLOTRON PRODUCTION OF Al-29 AND Ti-45 TRACERS FOR kGRlCULTUEAL STUDIES

Physiological roles of trace inorganic constituents in biological acid agricultural systeas are still incompletely understood. Radiotracer studies in such systems are useful to clarify the behavior and role of inorganic elements in lives and surrounding environments. We have recently started to investigate cyclotron production of inorganic radioisotopes as tracers in agricultural studies. In this paper, are'reported our recent results on cyclotron production of Al-29 (tj/2 = s«7 rain) and Ti-45 (t-j/2 = 3.09 h) and their tracer applications in agriculture. Al-29 and Ti-45 were produced via 26Mg(tt,p)29Al and Sc(p,n) Ti reactions, respectively. Excitation functions for these reactions and side reactions were determined with stacked foil method. Thick target yields of the reactions were also measured to estimate optimum condition for radioisotope production. Several radiochemical separation procedures were employed to separate these nuclides from target material (Mg metal and SC5O3, respectively), and by­ product radioisotopes. Adsorption of colloidal aluminum hydroxides onto cellulose powder from neutralized target solution was found to be effective for the separation of Al-29. About 7 0% of Al-29 produced in target could be recovered from the cellulose powder by elution with dilute HCl. More than 90% of Ti-45 was separated by solvent extraction with oxine from HCl solution of the target. Al-29 was used as tracer in the studies of adsorption of aluminum by soils collected from rice-fields and adjacent regions in Japan. The quantity of Al-29 adsorbed by the soil were influenced by the origin of the sample soil, co-existing minor constituents added to the solution, and pH. Although adsorption behavior of aluminum was largely affected by the change in pH due to neutralization on dissolution of the soil, complex formation with fluorine and organic chelates also proved to be an.impo'rtant factor for controling chemisty of aluminum in the soil-water system. Incorporation of Al-29 into plant through its root was also investigated. In the case of Ti-45, transfer of Ti-45 from a cucumber root to the leaves was found to correlate well with water transfer into the plant, and Ti- 45 was to be dissolved in water as chelate complex.

- 235 - Y-Z. Guo^, RE Ackerhalt, HF Kung, +Jiangsu Institute of Nuclear Medicine, WuXi, China and Department of Nuclear Medicine, SUNY at Buffalo, NY.. USA

PREPARATION OF [125I] [R)-8-IOD0-2,3,4,5-TETRAKYDRO-3- METHYL-5-PHENYL-1H-3-BENAZEPINE-7-0L: A DOPAMINE SPECIFIC IMAGING AGENT.

In developing new receptor-site specific brain imaging agents for SPECT (single photon emission computed tomography), (12SI] (fl)-8-iodo-2,3,4,5-tetrahydro-3-methyl- 5-phenyl-lH-3-benzazepine-7-ol (IBZP, SKF-103108A), a D-l specific dopaminergic binding agent, was prepared. Biodis- tribution of the [12SI] IBZP in rats showed specific cere­ bral localization in regions high in D-l receptors. In anticipation of the evantual clinical trial in humans a rapid, efficient and simple labeling procedure is needed. Two labeling methods were evaluated to optimize the labeling condition. The condition may be adopted as a kit form for preparing the [123]I— IBZP, which will be used for the clinical trial. Using a simple aqueous exchange reaction between [125IJ iodide and IBZP, [12SI] IBZP was prepared. The kinetics of the exchange reaction was evaluated in different pHs and in the presence of oxidizing agent, KIO3. The highest radiola- beling yield was obtained in water after heating at 100 °C for two hours. When the reaction was carried out in a pH 0 solution, no exchange occurred. This may be due to the formation of the hydrochloride salt which precipitated in the strong acidic medium. At pHs of 3, 5, and 7 the yield were lower than that in water. In the presence of 0.1 mg of KIO3 as an oxidant, a labeling yield of 80% can be ob­ tained at room temperature in two hours. At higher tempera­ tures the reaction rate was even faster. However, the labeled material was not as pure as that obtained without using the oxidant. It is likely that the oxidant also cata­ lyses side reactions which produce other impurities. The specific activity of this reaction has been achieved at the level of 30 mCi/mg (12.5 Ci/mmole). Carrier free [125I] IBZP was prepared by the chloro- amine-T method using BZP (SKF-R-83692) as the starting material. The reaction was very rapid (completed in a few minutes) and gave 80% yield. The nonradioactive starting material could be separated from the desired product on a silica gel column eluted with 100* methanol. The purity of the no-carrier added [12SI] IBZP was above 95* , as measured by HPLC with both gamma and UV detectors. The specific activity was close to 2,000 Ci/mmole. With minor modifications, it appears likely that the chioramine-T method is adoptable for preparing no carrier- added [i23J] IBZP in a kit form.

- 236 - Zhang Wenving, Ku Zengxin, and Huang Jin Beijing Municipal Research Institute of Environmental Protection, Fu Wai Ave., Beijing, China

STUDIES OF ADSORPTION, MIGRATION AND PERSISTENCE OF TOLUENE IN SOIL 3Y MEANS OF "C-LABELED COMPOUND

The adsorption, migration and persistence of toluene in i .1 soils were studied in laboratory using X"*G-labeled compound.

The adsorption experiments show that the adsorption effi­ ciency of the same soil varies with random sampling sho­ wing normal distribution. The adsorption efficiencies of toluene in different soils studied are not high. With Gaobeidian soil in toluence solution of- concentrations frpm 0.1 mg/1 to 2.3 mg/1, the adsorption isotherm equa­ tion is :

X 1.20 C0-974 m Kher1? X= weight of toluene adsorbed (ng;, m= weight of soil (g), C= the equilibrium concentration of the solu­ tion ( ng/ml ) . Leaching and column chrmatography tests show that the toluene is liable to transport in soil. The results of persistence tests show that the degrada­ tion of toluene is rather difficult, it volatilizes slower in arid soil than in damp soil. The half-persis- tence-lifes of toluene are about 70 days and 22 days respectively in arid and damp soil.

Although toluene is volatile, it may get into the soil with sewage irrigation and rainwater, and a part is adsorbed and perraeats and moves down with water. It may cause ground water pollution. This study helps the study of environmental capacity and impact of sewage irrigation on soil and ground water in Gaobeidian area. - 237 - Ding, W.D., Hu. Y.L., Chang, J.P., Xie, Y.Y., Jiang, M.S.. and Xu, C.F- Shanghai Institute of Materia Medica, Academia Sinica

REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC INVESTIGATION ON THE RELATIONSHIP BETWEEN STRUCTURE AND IN VIVO DISTRIBUTION OF HEPATOBILIARY AGENTS

Two C,R alkyl-bonded reversed-phase chromatographic systems • were used to determine the log k' values of thirty-six substituted acetanilido-iminoacetic acids of different polarity- The linear correlation was shown by the regres­ sion analysis between the log k' values of m- and p- subs­ tituted ligands and their theoretical hydrophobicities£7L . Ortho substitution decreases log K* value of a ligand while the molecular internal hydrogen bond increases it. There is a linear relationship between the log k' values of these ligands and the sum of distribution concentrations in liver, gallbladder and small intestine. The Tc-labelled comp­ lexes of strong hydrophobic ligands were mainly excreted by liver and gallbladder system while those of weak hydro­ phobic ligands mainly by kidney system. Ortho substitution was found to be able to accelerate hepatocellular transit time. The experimental results indicated that the hydropho- bicities of these ligands measured by RPHPLC may be useful as means of reference for searching effective hepatobiliary agents.

- 230 - 2hu„ T., Gong, J.L., Zhu, G.G.., Zhong, G.R., Du, L. Shanghai Medical University Shanghai, China

THE PREPARATION AND IDENTIFICATION OF TRITIUM LABELLED AGONIST AND ANTAGONIST OF OPIATE RECEPTOR

In order to study the principle of accupuncture analgesia, the RRA was chosen as the detection method, and a series of Tritium labelled agonist and antagonist of opiate receptor were prepared and used as tracers. 1, Six trituim labelled compounds were prepared. specific activity Radiochemicalpurity [1] 3-H-Dihydromorphine 3-H-OHM 70-85Ci/mmol 95% [2] 3-H-Naloxone 3-H-NAL 44-57Ci/mmol 95% [3] 3-H-Etorphine 3-H-E 33-44Ci/mmol 95% [4] 3-H-Dihydroetorphine 3-H-DHE 35Ci/mmol 95X [5] 3-H-Phencyclidine 3-H-PCP 38Ci/mmol 98% [6] 3-H-Leucine Enkephalian 3-H-Leu-Enk 18.9Ci/mmol 97% 2, All these tritium labelled compounds were prepared in a very simple tritiated system designed by our laboratory. The methods used were: [1] Catalytic reduction by trituim gas. [2] Catalytic halogen-Tritium replacement. [3] Catalytic gas and liquid exchange reaction. 3, All the precursors were prepared in our laboratory, and only 1-10 mg were used. 4, The main identification methods used were liquid scintillation counting, uv photometry or fluorometry, TLC or paper chromatography. From these results, the specific activities and the radiochemical purities were determined. Sometimes, the bioactivity was determined by mouse vasdeferens method. Besides, the tritium NMR was used to determine the labelled position of the compound. 5, The products were analyzed by RRA, and the specific binding to non-specific binding was equal to 8:1 to 13:1. - 239 - Zhuang.D-L., Ye.Y.L., Zhang.Y.L.. Zhou.M.Y.. Yao.F.Z- Shanghai Institute of Nuclear Research Academia Sinica. China

PHOTOSENSITIZED TRITIUM LABELING OF BI0-MACROM0LECULE LECTINS

Lectins, Con A , WGA and PHA, was successfully labelled with high specific radioactivity and good radiochemi­ cal purity with its biological activity preserved.

The better conditions for substituting hydrogen of Con A by tritium were studied. Tritium pressure (20 Torrjin 5ml quartz reaction vessel and exposure time (2hrs) were chosen to achieve isotope exchange reac­ tion between tritium and hydrogen of solid lectins under u.v. irradiation in presence of the photosen- sitizer at room temperature.

Since the tritiated lectins have no significant degra­ dation, it was purified by dialysis and affinity chro­ matography to remove exchangeable tritium. Labelled lectins were then analysed and identified by polyacry- lamide gel electrophresis and high performance liquid chromatography. The radioactivity and content of labelled lectins were determined. According to the number of subunit and weight of molecule, the specific radioactivity for each lectin can be calculated.

The highest specific radioactivity of Con A.WGA and PHA is 66.30 Ci/mM , 9.89 Ci/mM and 100.86 Ci/mM respecti­ vely. The radiochemical purity of each labelled lectin is higher than 95£. They all still preserve biological activity .

- 240 - JJ Billings. KF Rung, Department of Nuclear Medicine, SUNY at Buffalo, NY. USA

PREPARATION OF |>25I] N-(4-I0D0PHENYl)-N-[l-(2-PHENYL^THYL)]- 4-PIPERIDINAMINE:A FENTENYL ANALOG

In search of new opiate receptor imaging agent labeled with 1-123 for SPECT imaging (single photon emisssion com­ puted tomography), the chemical synthesis and radiolabelinif of the deproprionated fentenyl derivative, [125I] N-(4- iodophenyl)-N-[l-(2-phtti\ylethyl)"i-4-piperidLnaroin*i (IPPA) v.-AS prepared. The cold compound was synthesized by condensing 1- phenethyl—4-piperidone and 4-iodoaniline, and reducing the inline with sodium borohydride. The crude product was puri­ fied by column chromatography (silica gel, eluted with ethyl acetate 100*). The NMR, IR and UV/VIS spectrum are consistent with the expected structure (Figure 1).

Fig1 IPPA

The exchange reaction between [12SI] sodium iodide and IPPA was studied under several different conditions. The rate of the exchange reaction was dependent on the concentration of cold IPPA- At 50 °C, pH=~ 2, s 1 »g/s?l solution gave 99.51 yield in three minutes. When the con­ centration was dropped to O.lmg/ml, the reaction took two hours to complete. The kinetics of the exchange reaction was investigated further by studying the reaction rate with additional sodium iodide carrier (to further slow down the reaction). At 70, 80 and 90 °C, Ln(l-F) vs time , where F=fraction of exhange, showed a linear relationship. The exchange reaction is apparently a second order reaction. Based on the slops of these straight lines, the activation energy was calcultated (Ea = 15 Kcal/mole). The [125I] IPPA can easily be prepared by a simple exchange reaction and the exchange reaction may be adoptable to a kit formulation for clinical use.

- 241 - Tjioe, P.S., Van den Earner, C.J.A. „ Stolk, Th.M.W., Volkers, K.J., De Goeij, J.J.M. Interuniversity Reactor Institute, Mekelweg 15*, 2629 JB Delft, The Netherlands.

THE METABOLTSM OF SETJ-NTTE INJECTED IN MICE AND THE INFLUENCE OS IT OF THE HEAVY METAL PLAT1WJM>

Setenivns, injected as selesite, acts as a protective agent against the toxicity of heavy metals such as Hg and Cd. A similar protection was recently reported by Naganuma (1) against the toxicity of Pt, an effect which has been confirmed in our laboratory (2). Pt was chosen as the heavy metal, because it is part of cis-diamminedichloro- platinum(II) or cisplatin, a potent, anticancer agent. The selenite-metabolism was studied in mice using subcutaneous in­ jections of 75se-selenite. When '^Se was injected alone its retention- time curve for the total body followed a biphasic mode; a fast ex­ cretion phase of '^Se for the first day and a slow one with a half- life of 8 days. The retention of 7$Se in the tissues, particularly in the liver, showed a similar tendency to that found for the total body. In the subcellular fractions of the liver, most o f the ?5se was located in the cytosol; in the kidney about half of the 75Se was lo­ cated in the particulate fraction. When cisplatin was administered simultaneously, a different '*se- metabolism was observed: a) The total body retention and the retention in some tissues of '^Se increased with increasing amounts of cisplatin 2dts£n£scer*i. b} Th~? subcellular ^^^e-distri.b\it\on in liver and kidney showed a shift to the particulate fraction, c) In the iver almost no change was seen in the distribution of Che 7$Se over tie cytosolic proteins, but in the kidney a shift to proteins of lower molecular weight (13,000 D) was observed. With Pt^+ instead of cisplatin, the effects on the.selenite-metabolism were even greater. The Se content of some tissues of mice, treated with selenite or with selenite and cisplatin, was also analysed. It was found that selenite treatment increased the Se content in liver and kidney, but that the increase became much larger when selenite was administered simulta­ neously with cisplatin. These results show that selenite interacts with Pt, but the evidence obtained indicates that this interaction is probably of a different nature to that with Hg or Cd.

References. (1) Naganuiaa, A., Satoh, M., Yokoyana, M. and Imura, N.: Res. Commun. Chem. Pathol. Pharmacol., 42 (1983) 127-134. (2) Tjioe, P.S., Van den Hamer, C.J.A., Stolk, Th.M.W., De Goeij, J.J.M. and McVie, J.G.: Cancer Chemother. Pharmacol., submitted for publication. - 242 - Wang, C.P.. Zhang,, J,D, „ Rong. T.W. „ Lu, X.F. Shanghai Institute of Nuclear Research, Acade-ia Sir.ica

CYCLOTRON PRODUCTION OF THALLOL'S CHLORIDE 201Tl INJECTION

•>01 The first production in Chins of thailous chloride Tl 2Q1 injection is described. ~TI is produced via nuclear reaction Tl(p,3n) Pb after proton activation of natural thallium in a specially designed Z7Z cooling system. For the separation of the Pb-activity from the Tl target, a combination of extraction of Tl(III) with isopropyl ether and additional purification of the remaining Pb(II) with an anion exchange column (201x8 resin) is used.After a decay time' of 32h, during which an optimum growth of 9CM " 201 ~T1 takes place, the separation of carrier-rree Tl 203 from the Pb activities is carried out by a second anion exchange with the same exchanger. Dependence of the percentage extraction of Tl(III) from HCl solution into isopropyl ether on the acidity and concentrations of Tl(III) in aqueous phases is determined. The thick *201 target yield of Tl is 0.4 mCi^uAh. The product possesses a radioisotopic purity >98.5% and a radiochemical purity >98%. It is a sterile, isotonic and pyrogen-free solution with a Tl content of

- 243 - David R. Elmaleh and Hiro Kizuka Massachusetts General Hospital Department of Radiology Fruit Street Boston, MA 02114 USA PREPARATION: OF N-CPC-METEYL) CHLOPPHENTERMTNE (J-LC-NMCP) THROUGH METHYLATION OF CHLORPHENTEB.HIXE TRIFLUOROACETAMIDI N-I^c-MethyllChlorphentermine (-^C-NMCP) has recently been developed in our laboratory as a potential brain blood flow agent for PET studies (1). Initially, -L1C—NMC? was prepared by the reaction of chlorphentermine and 11CH3l in DMF with heating *t 140°C for 5-1Q min and followed by HPLC purification. The radiochemical yield of •L1C-NMCP was substantially low because the reaction gave a mixture of mono-, di- and quarternary amines. To improve the radiochemical yield of 11C-NMCP, we investigated the Gabriel-like transformation of the primary to the secondary amine through a sequence of acylation, ionization, alkylation and hydrolysis (2).

N-trifluoroacetyl, N-acetyl and N-formyl derivatives were prepared and examined as possible intermediates for this study. Hydrolysis of the N-trifluoroacetamide was quantitative after 3 min of heating with KOH/EtOH whereas that of the other two derivatives was less than 10%. Thus the N-trifluoroacetamide was chosen for the radiolabeling experiment as shown in Scheme 1. The trifluoroacetyl derivative (II) was prepared from chlorphentermine HC1 CI) and trifluoroacetvl anhydride in the presence of two equivalents of triethylamine in ether with a 90% yield. Ionization of II was carried 11 11 out with NaH in DMF. CH3I was prepared from C02 according to the published, procedure (3) and was distilled into the reaction vial containing the mixture of II and NAH. The reaction mixture was heated at 140°C for 7 min and the ^Cl^-labeled intermediate III was extracted with ether. The solvent was evaporated and 0.3 ml KOH/EtOH (10%) was added followed by heating at 100°C for 3 min. The resulting residue was diluted with H20 and acidified with IN HC1 to pH 5. TLC analysis using a silica gel plate and HPLC showed that the radiochemical purity of ^C-NMCP was > 98.5%. The radiochemical yield was approximately 20%. 1. Marazano C., Hazierre M., Berger G., and Comar D., Int. J. Appl. Radiat. Isot., 28.:49-52 (1977). 2. Kizuka H., Elmaleh D.R. , Boudreaux G.J., Strauss H.W., Ackerman R.H., and Brownell G.L., J. Nucl. Med. 27; (1986) (in press). 3. Nordlander J.E., Catalane D.B., Eberlein T.H., Farkas L.V., Howe R.S., Stevens R.M., and Tripoulas N.A. , Tetrahedron Lett, 50.: 4987-4990 , (1978). - 244 - J. Hiltunen and P. Penttila-Hiltunen Technical Research Centre of Finland Reactor Labaratory Otakaari 3 A SF-02150 Espco Finland

PRODUCTION OF 165Dy FOR 16SDy-FKRJ?rc KYDPOXIDE HUCPavXBECXTEC

165Dy-ferric hydroxide macroaggregate (165Ey-FHMA.) is very promising new radiopharmaceutical for intra-articular radiation synovecbony-

16SDy has favourable physical characteristics: half life of 2,3 hrs, almost pure beta emission, gamra energies are 361 keV and 95 keV with low intensities of 1,1 and 4,0 %:s. The maximun soft tissue penetration of beta particles are 5,7 irni (about the inflamed synovium). The method of preparation is described else<»*}ere /l.

The of 16**Dy is 28,1 % and it activates both directly by [n.y) reaction to 165Dy (a = 800 b) and l6,,Dyln.Y) 165m0y * l6S Dy (a ac= 2100 b). The irradiations were made by Triga Mark II reactor in the dry activation tube with flux of 4,25xl0l2n/cm2s and in central thimble with neutron flux of 1013 n/cm2«s. The determinations of activities were nade by a ccximercial ionization chambers, which were calibrated for l65Dy with multichannel analyzers. Which were calibrated for 165Dy with multichannel analyzer and Ge(Li)-detector.

Dy 0, was irradiated in dilute nictric acid. The irradiations in activation tube were made in polyethene tubes. The volume or specific activity of irradiated did not affect remarkably to the yield

Table Irradiation of Dy in the activation tube

Tims of MBq/mgDy Volume MBq/mgDy Dy MBq/mgDy irradiation concentration 1 h 2600 0,1 ml 1800 3 mg/ml 2700 2 h 3300 0,2 ml 1900 6 " 2800 3 h 4000 0,6 ml 1800 12 " 2800 4,5 h 4400 2,0 ml 1800 18 " 2700

1. Sledge, C.B. et. al. Intra-articular Radiation Synovectomy, Clinical Orthopaedics, Jan-Feb, 1984.

- 245 - Anthony gggn Aronic mergy of Canada Limited JlSVarch Road. Canada, On-twro KZK 1X3

SELECTION, AFPLlCATIOK AND WALTS IS OF RADIOLAHBJLED CtXPCXJMlS IN OIL RESERVOIR STUDIES

The recovery of oil from an underground reservoir can be greatly enhanced by the Inject'on of ono or mora of a varjaty of liquids end gaaas - ac-col led "/ l

These parameters can only be measured using tracers. These materials, having distinctive physical or chemical characteristics, are Injected along with the flooding fluid, and then, after moving -through the reservoir, eoeree. greatly diluted, with the production fluids. Radio- labelled compounds ("radiotracers") are particularly suitable materials since (a) they, do not occur naturally, and Cb) they can be detected In wry low concentrations. A complex reservoir will require a number of different tracers to determine unambiguously all the various fluid pathways. Selection of radiotracers for this role Is based on the following criteria:

(I) the ability of the tracer to mimic properly the relevant fluid I.e. It must show low reactivity with the host rock material of the reservoir, (ID the existence of a radioisotopic form of the tracer, such that the Injection of modest amounts of activity will give measurable amounts In the produced fluids. (Ill) compliance with nuclear regulatory and environmental conditions.

For the radloenalytlcal chemist, a further consideration concerns the decay scheme of the radioisotope; Beta emitters pose no shielding problems, but their determination later can Involve a lengthy clean-up process, and simultaneous counting may be difficult.

Gamma emitters require much greater shielding but several can be measured directly and simultaneously In a sample of produced fluid.

Application of any radiotracer requires suitable and safe equtpraent. Clearly the equipment must be TeaK proof, and provide proper radiatTon ihTetolng. *t must also be mobile, rugged, and not require any external power source.

The analytical methods used depend on the nature of the fluid, and the tracer.

(II) for 11quId products (a) Beta emitters:- Oil/water separation. Distillation. Liquid scintillation counting. (b) Gamma emitters:- 01 I/water separation. Spectrometry.

This paper describes the radioisotopes currently being used as tracers, and their preferred chemical forms, for both gaseous and liquid Injections. The principles and details of a field system for their safe Injection Is also discussed. Analytical procedures are presented, with results for various Isotopes In various circumstances. The relationships between these results, reservoir conditions, and enhanced oil recovery are also Illustrated.

- 246 - RJJTanagan. J.S.Wilson and L.I.Wiebe.

Mcrck-Frosst Canada Inc., Kirkland, Quebec H9H 3L1, Canada, and Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G 2N8, Canada.

RADIOCHEMICAL REACTORS. A NEW TYTE OF GENERATOR FOR THE SIMPLE SYNTHESIS OF HALOGENATED RADIOPHARMACEUTICALS.

A aiaioi ilnwbacL ia tUc IUC of liilu^iiitcil ladiopi'-atnuctulieals

Tms reactor allows the facile synthesis cf organic molecules labelled at predetermined positions with either radiobrornme or radioiodine. The reactor is similar to a technetium generator in that it contains a preloaded column which is then eluted to provide the labelled material. The column is eluted with a solution of radiobromide or radioiodide. The halide is activated in the column to the lero-valent form which then reacts with the resin to produce the desired product. The formation of the product simultaneously cleaves the product from the resin which is then eluted at high specific activity.

The reactor consists of a two pan resin bed. One part is an oxidizing resin containing an N-chk»o-species which reacts with halide to form the corresponding iodine or bromine monochteride. The second resin contains a covalently bonded form of organomsreury compound in which the substrate is preactivated by mercwy towards electrophilic substitution. The organomercury substate can be bonded to the resin m a number of different ways but the most general method is via a thiol linkage.

r——Add«d To Column

m|e + 'RMln— NCI • mICl + 1R«iln—NH

mJCI + 'RMln— SHgR •> "MR + 'Rasln—SHgCI I » Elulid From Column

Tne halogen monocrtlonde reacts at the carbon-mercury bond to selectively cleave that bond (1) and at the same time releasing the halogenated product. The mercury is retained in the column since it is covalently linked to the resin. There is no reaction between the N-chloro resin and organomercury iesin, and the halogen mnnechloride reacts in a polarized fashion with the organomercury bond with no production of the corresponding chloro-substrate (2).

A number of different resins have been examined for suitability in this method. While each resin examined has some drawbacks the best examples we have found to date offer radiochemical yields of 90% or greater and radiochemical purities of greater than 95%. Typical elution times are of the order of 1 to 3 minutes.

Radiochemical reactors of this type using previously synthesized chloromercury compounds (3), (4), have been prepated for 6-halo-cholesterol, 6-halo-epiandrosterone, 6-halo-androstenediol, 6-halo-pregnenolone. 6-halo-pregnanediol. 7-halo-estradiol-6-ene and 4-iodo-N-isopropyl-amphetamine.

1. R.J.FUnagan, F.P.Charleson, E.l.Synnes and L.I.Wiebe, In proceedings Fifth International Symposium on Radiopharmaceutical Chemistry, Tokyo, Japan. July, 1984. 2. R.J.FUnagan, F.P.Chatlesort. E.l.Sjnnes. L.I.Wiebe, Y.X.Theriault and T.K.Nakashima. Can.J.Chem. 68, 2S53. (1985). 3. R.J.Flanagan, F.l'.Charleson. E.l.Synnes and L.I.Wiebe, J.Muc.Mtd. in press J. R.J.Flinagan, V.V.Somayaji. J.Wilson, F.r.Charleson. L.l.Srnnes and L.I.Wiebe In proceedings International Symposium on the Radlohalogens Banff, Alberta, Canada. September 1985. 5. R.J.FUnagan, V.V.Somayaji and Leonard I.Wiebe, Int.J.App.Rad.lsot. in press

- 247 - Lin. Q.F. , Vang, W.C., and Liu, T. Institute of Atomic Energy, Beijing, China Zhu.X.M. , Wang.S.Z., Zhou, Q. , Liu, G.D., Lian, L.J., XU.X.F. PUMC Hospital, Beijing, China

PREPARATION OF I-2jl-ANTI-lFP-IgC OF HIGH RADIOACTIVITY FOR RAD10IMMUNOTHERAPY '

An aseptic preparation process of I-131-anci-«FP-IgG with high radioactivity and its clinical use have been investigated. The chloramine-T technique is selected for the radioiodination and Sephadex G-50 column of ol5xl30mm is used in the purification. The yield is more than 85%. The specific activity is 370-518 MBq (10-14mCi.)/mg. protein. Radiochemical purity is above 90Z. The processing system is sterilized with peroxy-acetic acid. The final product obtained is sterile and pyrogenfree suitable for intravenous injection.

It has been applied to five patients for clinical experiment. The total dose of each patient is 1480-3182 MBq(.40-86mCi .) . From radioimmunoimaging, the 1-131 labeled antibody is seen concentrating in the cancer cells. The clinical examinations also indicate that the FP concentration in the patient's blood is reduced rapidly to normal level and no side effect is observed, after radioimmunotherapy.

- 248 - Yi, M.6., and Xiao, L- Institute of Atomic Energy, Beijing, China Feng, J., and Zhang, K.R. Institute of Radiation Protection, Taiyuan, China

LABELLING OF A NEW CHELATING AGENT (H-73-10) WITH TRITIUM AND CABON-14

A new chelating agent is used for decorporation of radionuclides: Plutonium, Thorium and Uranium. The effect of this new medicine is better than DTPA, an outstanding decorporating agent for the last twenty years. The results of acute and subacute toxicities of mouse, dog and monkey, and a series of pharmaceutical tests, show that this medicine is not more toxic than DTPA. The tritium or cabon-14 labeled new chelating agent is used for the study on the absorption, distribution, metabolism and excretion in animals. The labelling method of 14C-H-73-10(n) is that a 14C-labelled condensing agent reacts to ethyleneamine and hydroxybenzenesulphonate salt in glacial acetic acid. Specific activity of the product is 1.02

- 249 - fiuang, Y., Wis, Y.H., Kaug, X.Y., Liu, y.j-. , Departisent of Technical Physics, Guo, Z. Q. , Wang, S.Y., Wang, Z.Q., Department of Biology, Peking University, Beijing, China

LABELLING OF IgG AND MONOCLONAL ANTIBODY WITH 169Yb AND51Cr

Employing ovine antibody against human IgG as a model protein, the methods and influencing parameters of rapid and reliable labelling of IgG with Yb and Cr were investigated.

In both labelling processes cycloanhydride*- of DTPA was used as a bifunctional chelating conjugate to make prior linkage of DTPA to IgG, then followed by the metal chelation.

In labelling DTPA-IgG with Yb, Yb-citrate was used to avoid the hydrolysis of Yb(III). The conditions of binding reaction of DTPA and IgG, and attaching reaction of Yb to DTPA-IgG were determined in detail.

An active Cr ion species was procured by the reduction 2- of CrO/ with NK-.0H'HC1 in a neutral medium. Via this novel activation step IgG molecule was gently attached with Cr ion without loss of its immunoreactivity.

Using these conditions previously developed from IgG labelling studies, the labelling of monoclonal antibody against epidemic hemorrhagic fever (EHF McAb) with 169yb and Cr was performed, and their immunoreactivities were assayed. The labels will be applied to act as either tracers or radioimmunoassay agents.

- 250 - " 5. General Session

i

- 251 - G.Marx, A.Bestanpouri, R.Droste, V.Schonemann, D.Wegen sad Hou Hui-qi Institute for Inorg. and Analyt.Chem. Dept.of Radiochemistry, FU Berlin (F.R.G.) and Fudan University, Nuclear Sc.Dept. (Shanghai/China)

RADIOCHEMICAL INVESTIGATIONS ON CORROSION OF VALVE METALS AND STAINLESS STEEL UNDER THE INFLUENCE OF PLUTONIUM

In presence of Plutonium under the practical conditions of the PUREX process the corrosion behaviour of valve elements (HE, Ti.Zr.Ta, Nb) and -stainless steel was investigated by use of impedance measurements in addition to radiochemical and electrochemical methods, based upon a new technique of combined applications of neutron activation analysis and normal electrochemical procedures. This new radioisotopic method has the advantage to be able to determine simulianeously the amount of material dissolved due to corrosion and also that special quantity being used for forming the oxide layer of the valve metals. In addition the impedance measurements also performed simultaneously give informations about the oxide layer, its physical structure and characteristics being changed by the amount of plutonium, incorpo­ rated. Last but not least the radioisotope method applied tc the investigations on stainless steel makes practical anodic and cathodic currents be calculated from the corrosion rate of the various components of the alloys, labelled by NAA, which for the first time makes informations about partial corrosion be obtained continuously. The Influence of Fission products and of materials dissolved by corrosion on the corrosion potentials of stainless steel, were investigated systematically at various temperatures and at a variety of HNO3 concentrations- In addition the corrosion behaviour of stainless steel in presence of plutonium has been intensively studied, including investigations of the surface by use of various methods.

- 252 - E. Holm"*", B. Persson++, A- Aarkrog+++, H. Dahlgaard""" and R. Fukai .

+ International Laboratory of Marine Radioactivity, IAEA, Monaco ++ Department of Radiation Physics, Lund University, Sweden +++ Risa National Laboratory, Roskilde, Denmark

ACTINIDES AND ISOTOPIC RATIOS IN THE GREENLAND AND BARENTS SEAS

During the Swedish arctic expedition, YMER-83, a Urge number of surface seawater samples and suspended material was collected for actinide analysis. The aims were to investigate present levels,origin, association with particulate material and isotopic ratios of natural and antropogenic actinides and radiocesium. The results are summarized in the table below. , For 238U a mean activity concentration of 34*1.2 mBq 1~ (n=35, 1 S.E.) is slightly lower than that found in other ocean waters, but the activity ratio 234^238^ 1.13±Q.03 is similar. A lower concentra­ tion would indicate inflow of freshwater. „3Q "2jh originates mainly from riverdrainage, Th from of uranium and ||§Th from dissolution and radioactive decay of 22oRa> Tne source of ,„Th is distributed rather homogenously in the oceans while that of Z3ZTh does not. One might expect the different thorium isotopes to behave similarly after entering the oceans. A good linear correlation between 232-ph and z^Th was found: C(Th-232) = 1.23+0.31-C(Th-230) while the correlation: C(fh-232) = 2.2+0.024- C(Th-228) was poorer. For the plutonium isotopes 238pu> 239+

Table 1. Activity concentration levels and association with particulate matter. 234 238 223 230 232 Isotope (J lJ Th Th Th

Activity cone. (39.1*1.4)x103 (34.6±1 .2)x103 340*30 16±2 6.4±2.0 (mBq m~3) Particulate (%) 34*5 19*4 39*10 > 0.45 pi — — 238 239+240 241 pu pu DP u 241Am "'cs . Activity cone. 0.35*0.14 13±2 90*30 1.7-0.5 (10i2)x103 (mBq m~3j Particulate^) 29-13 33*3 35-10 39*9 0.9*0.4 - 253 - Satoru NAKASHIMA*, Motomi KATADA*, Izumi MOTOYAMA**, and Hirotoshi SANO* •Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Fukasawa, Setagaya, Tokyo 158 ••Department of Chemistry, Faculty of Engineering, Kanagawa University, Rokkakubashi, Yokohama 221, Japan MOSSBAUER SPECTROSCOPIC STUDY ON THE MXXED-VALENCE STATES OF 1',1'*"-DI(METHYLBENZYL)BIFERROCENIUM TRIIODIDES

1* ,1* ' * -Di tmethyLben7;yl^biteTtocenes -were synthesized and their monocation salts were investi­ gated by means of M6ssbauer spectroscopy at various fcersperatures in order to study the effect of the substituents on the mixed-valence states of biferrocenium monocation salts. The Mossbauer spectra of 1M"'- !«• o.-y-.w,. dibenzylbiferrocenium triiodide show :; *» an the remarkable temperature-dependence _- '• -* corresponding to a trapped-valence S7 0- s.tate at low temperatures and to an Joo •,—«. .-c^-v*** averaged-valence state at high tem­ peratures near room temperature. On • . i V the other hand, the Mossbauer spectra loo)-.-:.i of methyl-substituted analogues show 2M* a complex feature, as shown in Fig. m-

These results suggest that the posi­ loo •»'-.'^-=-^.--=.., tion of methyl group on the benzyl ISK substituent has an important effect

on the mixed-valence state of di- loo (methylbenzyl)biferrocenium triio- dides. The crystallographic and M P- structural information on these loo • <«wsW'^~?xrw?~'~~^ compounds will be helpful to verify M «*

the mechanism of the substituent 1 1 1 1 1 1 1 1 1

effect on the biferrocenium triio- y«i»ctf0 •* / fl •»•-*. •v dides.

- 254 - M. Suzuki, A. Uehara, M. Yanaga* and K. Endo* DepaYtment of Chemistry, Faculty of Science, Kanazawa University, Farunouchi, Kanazawa, Ishikawa 920, Oapan "department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Fukasawa, Setacaya, Tokyo 15S, Japan

ANTIFERROMAGNETICALLY COUPLED DINUCLEAR HIGH SPIN tRON(II.III) MIXED VALENCE COMPLEXES WITH THE DINUCLEATING LI6AND, L-py or L-Bzim

Three types of the dinuclear iran(Il,IH) mixed valence complexes I III I III [Fe^ ' (L-py)(RC0O)2](BF4)2-nH2O, [Fe| ' (L-py)(CH3COO)(0H)](BF4)2-

2H20, and [Fe^'^^L-BzimXRCOO^COHJjBF^H^O. with the dinucleating "ligand (L-py or L-Bzim) were prepared, where HL-py represents 2.6- bis[bis-2-pyridy"lmethyl)aminomethyl]-4-methylphenol, HL-Bzim 2,6- bis[bis(2-benzimidazolylmethyl)aminomethyl]-4-methylphenol, and RC00H acetic acid or benzoic acid. The presence of iron(II) and iron(III) ions in 1 : 1 molar ratio is evidenced by M8ssbauer spectra, which is also confirmed by chemical analyses. All the spectra can be resolved into two sets of quadrupole doublets. The quadrupole splittings A (isomer shifts 6) in mm/sec at 78 K are 2.06 - 3.37 (1.08 - 1.85) and 0.40 - 0.96 (0.46 - 0.51), which can be identified as arising from high spin iron(II) (S = 2) and high spin iron(III) (S = 5/2) moieties. respectively. Magnetic susceptivility measurements over the tempera­ ture range of 80 - 300 K' revealed that high spin iron(II) and high spin iron(III) centers are antiferromagnetically coupled with :pin coupling constants of -4 to -8 cm . Such antiferromagnetically coupled dinuclear iron(II,III) mixed valence centers have been shown to exist in the iron proteins, pink uteroferrin and semi- methemerythrin. These also exhibit two sets of quadrupole doublets. The values reported are 2.68 (1.24) for iron(II) and 1.84 (0.53) for iron(III) in pink uteroferrin,. and 2.59 (1.16) for iron(II) and 1.57 (0.57) for iron(III) in semi-methemerythrin (sulfide derivative of methemerythrin), respectively. The quadrupole splittings of iron(III) moieties in the iron proteins are significantely larger than those of the present complexes, suggesting a remarkable difference in the stereochemistry between the iron proteins and the present complexes.

- 255 - H. Feuersteirj Abt- IT. Kerhforschungszentrum Karlsruhe GmbH, Postfach 3640, 7500 Karlsruhe, West-Germany

BEHAVIOUR OF RADIONUCLIDES IN SODIUM COOLED REACTORS A REVKW

Radionuclides in primary circuits of sodium cooled fast reactors are of great importance for the operation of the plants. They can be devided into groups by different ways, e.g.: - intrinsic nuclides like Na-22, Na-24, Ar-41 - activation products from impurities, e.g. Zn-65 or Ag-llOm - corrosion products - fuel, uranium and plutonium * - volatile and non-volatile fission products'.

The nuclides of•the different groups have a different impact on reactor operation and availability. The last review was published in 1979 (1). In the mean time experimenta work continued in many countries for a better understanding of the problems. More operating experience was gained with the reactors B0R-6C BN-350, BN-600, RAPSODIE, PHENIX and EBR-II. The following new reactors went into operation: KNK-II, JOYO, PFR, FFTF, SUPERPHENIX and FBTR. The construction of 5IW-300 in Germany is compTeteo", tfie plant is wait"! for start-up licence. One reactor, RAPSODIE, was shut down. The decommissioning of the DFR proceeded. Fast breeder reactors are now at the edge for commercial power plants. The general knowledge increased considerably. Some problems seem to be solved - e.g. removal of cesium from the sodium 7, while others got more emphasis - e.g. the question of fuel contamination -. This paper will make an attempt to summarize the knowledge of today.

(1) H. Feuerstein, A.J. Hooper and F.A. Johnson, Atomic Energy Review 17 3(1979)

- 256 - R.T. LOWSON & S-A. SHORT Australian Atomic Energy Consnission, Lucas Heights Research Establishment, Private Mailbag, Sutherland, N'.S.W. 2234, Australia.

GROUNDWATER RADIOCOLLOIDS IN THE VICINITY OF SOME AUSTRALIAN URANIUM ORE BODIES.

Investigations have been made of the distribution " of radionuclides of the uranium , in the solute and colloidal phase, in the groundwater in the vicinity of some Australian uranium bodies. One of the ore bodies is located in Cretaceous gravels in the Ashburton River region, Western Australia, the others are in Lower Protero'zoic sediments in" the Alligator Rivers region of the Northern Territory.

The groundwater was sampled by extended pumping and ,/the colloid recovered using an ultrafiltration membrane with a molecular weight cut-off of 100,000. The groundwater samples contained colloidal material retaining measurable quantities of uranium and thorium isotopes. The principal uranium isotopes 238U and 23**U are predominantly in the solute phase rather than in the colloid phase. However, significant proportions of the total amounts of thorium isotopes 23aTh and 228Th are associated with the colloid phase. These findings suggest that although the transport . of colloids in groundwater does not contribute significantly to the migration of uranium, it contributes significantly to the transport of thorium.

- 257 - H. H. Stana and K. Ch. Stade ^ x) Inst. f. Radlocheui., Kucl- Res. Center, Karlsruhe/F. R.'Gemjany

Kenik.Betr.Ges.TabH, Eggensteln-Leopoldshafen./F. R. Germany

15 YEARS OF RADIOCHEMICAL SURVEILLANCE OF THE KNK PRIMARY SODIUM

KNK is the first German experimental N^a-cooled Fast Breeder Reactor. It went critical foe \X\n first Umtj in 1971, auU was aoersled *.ilh a thermal core as KNK-I until September 1974. After remodelling it went critical again with its first fast core (KNK-II/1) in 1977. Radionuclides in the primary coolant are either activation products of metallic impurities or - after fuel pin failures - fission products and possibly washed-out fuel. It v/as possible to determine gamma-emitting radionuclides without radiochemical separations by means of a high- resolution Ge(Li)-detector in connection with multichannel-analyzers. After decay of Na-24, main activities were Na-22, Mn-54, Zn-65 and Ag- 110m. Smaller activity concentrations of Sb-124 and Ta-182 were neasured regularly, Co-60 and Sb-122 occasionally. During KNK-I operation no fuel pin failure occured. The source of very small amounts of fission products (Ba-La-140) was tramp fuel on the fuel element surfaces. After 150 effective full power days KNK-I was shut down, the specific activity of Na-22 was 9.6 kBq/g Na at that time. After start-up of KNK-II, Na-22, Mn-54, Zn-65 and AgrllOm increased furthermore, Sb-124 was measured in varying amounts, Co-58, Co-60, Sb-122 and Ta-182 now and then only. During operation with purposely defected claddings of short, experimental fuel pins, 1-131, Cs-137 and sometimes Cs-134 was found in primary Na samples. The sampling station may house up to seven crucibles; it was therefore possible to investigate the reproducibility of the whole sampling and measurement procedure, and to check the influence of the crucible material (glass, steel, Ni) on the results. In 1985, two fuel pin failures occured. KNK was operated for several weeks on full power with each of these failures. Zr-Nb-95, Ru-103, Ru- 106, 1-131, Te-I-132, Cs-134, Cs-136, Cs-137, Ce-141 and Ce-144 were released into the Na from the failed fuel pins. Filter sampling indicated in addition alpha activity of fuel particles in the primary coolant. The deposition behavior of gamma-emitting radionuclides on the walls of primary piping and components was checked each year during shut-down periods. A portable gamma-spectrometer with a high-purity Ge-detector was used for these measurements in the primary cell. After extensive screening tests with various materials, small, experimental radionuclide traps were tested in the primary sodium sampling station for the removal of radionuclides from the flowing Na. Ni packings were very successful for the removal of Mn-54 and Zn-65, carbonaceous materials for Cs isotopes, and sintered steel filters for particulate materials.

- 258 - K.Bachmann, G. Hartmann, H. Klenk, D. Projahn Fachbereich Anorganische Chemie und Kernchemie Tecfcinische Hocbschule Darmstadt, FRE

RADIOECOLOGICAL STUDIES OF 239PU AND NATURAL RADIONUCLIDES

239 Most of the Pu which is now Found ubiquitously distributed in the atmosphere, in plants and in the soil has its origin in the nuclear bomb tests of the sixties. In the last two decades, the stratosphere and the upper layer of the soil act as source of 239 further transport of Pu. Specially, the phenomenon of re- 239 suspension of Pu is not well understood due to the great number of parameters which influence the rate of resuspension. We have taken a number of profiles in different soils and measured the concentrations in order to determine the migration velocity and the reduced amount in the upper layer. The trans­ port mechanism within the biosphere depends on the size distri­ bution of the Pu-particles and the deposition velocity which is a function of the chemical composition. A differentiation between airborne particles and resuspended particles is made 239 by size fractionation. In the case of Pu, however, it is necessary to use additional characterization. Vie have therefore characterized the soil and the airborne particles by the chemical 71n ??fi composition and by the Pb / Ra concentration.

239 As to the question of the uptake of Pu in plants, we analyzed 239 the concentration of Pu in the needles of Picea Abies over several years. Using different washing procedures, it can be 239 demonstrated that more than 80 % of Pu is adsorbed whereas 239 only a small amount of Pu might be taken up by means of the foots. It is not easy to determine the amount which is adsorbed on needles and leaves since Pu(is rather strongly fixed.

- 259 - Sheng, H.Y., Chen, Y.H. , Yuan, Q. Shanghai Institute of Organic Chemistry, Academia Sinica, Shanghai, China

STUDIES ON LITH.IUH ISOTOPE SEPARATION BY THE. NEUTRAL LIGAND SYNERGISTIC SYSTEMS OF ARYLAZO-BETA-NAPHTHOLS AND BETA-DIKETONES

In the past two decades three p-diketone-neutral ligand synergistic systems were reported in literature, in which DPM, DR.M and HFDMOD were used as extractants, but the reported Li* isotope separation effect («<-value) was quite low (<< =1.003)- Since 1970 some new synergistic systems have been investigated in our laboratory and it was found that the new systems provide a higher extractability for lithium and much higher J3Li/Na.

This paper reports thed-values of a variety of neutral synergistic systems with nine l-aralazo-2-naphthols and fifteenp -diketpnes as chelating agents and twenty three componds as neutral donors. It is found that the <*" -value of a system is mainly dependent on the strength of the intratttolecular hydroqert bend snd the j>Ka of the exirzetant, and also on the extent of donacity of the neutral ligand. The pka of the extractants and the strength of the intramolecular hydrogen bond (estimated by AS OH and Apka) are measured. If a given system is chosen in accordance with these criterions, its o< -value can reach up to 1.009-1.010, which is two times thert-value of the systems reported in literature.

In contrast with crown (cryptand) -system, the heavy isotope 7Li is enriched in organic phase in our system. These two different types of isotope exchange reaction are discussed in detail. The thermodynamic parameters of the extraction reaction of these systems are evaluated and compared.

- 260 - Fan,W. Mu,W.T. Gaggeler.nt Sun,X.R. Ma,J.T. Yang.W.V. Xie.X.J. Zhou.L.L. Institute of Modern Physics, Academia Sinica Lanzhou, China THE DETERMINATION CF ADSORPTION ENTHALPIES OF TL-204 BY ISOTHERMAL GAS CHROMATOGRAPHIC AND THERMOCHROMATOGRAPHIC METHOD'S The adsorption enthalpies of Tl-204 en the Ni surTa.cc were determined by isothermal gas chromatography with H~ and Ar as carrier gases and by thermochroroatography with Ar and air as carrier gases respectively. TT-204 used in the experiments vas in the chemical state of 20^Tl(N0,),. The results are as follows:

AHa(KJ/mol) carrier gases iso.gas chrom. thermocbrom.

H2 -109.8±6. 1 Ar -47.3-3.9 -56.9-4-3 air -124..oi37.7 -50.5-4.1 -23.5-1.8

According to the chemical properties of Tl, we con­ sider that - 109-8KJ/mol in H_ gas is the adsorption enthalpy of T120, -47.3 and -56.9KJ/mol in Ar gas are the AH§. of^T^O.,. In air carrier gas, three AHS were obtained corresponding to the values in H2 and

Ar. -124.0KJ/mol is the AHa" of T120 and -50.5KJ/mol is the AHa of T1-0-. -23.5KJ/mol is prcbatly the

AHa of--Tl20 . which should be confirmed by further experiments. + Gaggeler,H., GSI, Darmstadt, F.R. Germany.

- 26i _ .Y. Yanaaa* T. Hiura. K. Endo, H. Nakahara, S. Ikuta. H. Takeda* Departnent of Chemistry. Faculty of Science. Tokyo Metropolitan University, Fukasawa. Setagaya, Tokyo 158, Japan *Oepartment of Chemistry, Faculty of Science, Toho University, Miyama, Funabashi, Chiba 274, Japan

STUDIES OF THE ELECTRONIC CHARGE DISTRIBUTION IN ORGANOANTIMONY(V) COMPOUNDS BY MEANS OF MOSSBAUER AND NMR SPECTROSCOPY

Pentavalent organoantimony comoounds- of the type R-SbX_ have been investigated for the structure, bonding and electronic state, by means of X-ray diffraction, vibrational, NQR and M8ssbauer spec- 121 troscopy, by many workers. The Sb MBssbauer spectroscopy is a useful method for the investigation of the electronic configuration, especially around the antimony atom, with its two parameters, the isomer shift and quadrupole coupling constant. Therefore, if it is used in combination with other spectroscopies, it is possible to elucidate how electrons are redistributed throughout a molecule when some ligands aVe varied. ;We have'performed the 121Sb MBssbauer and the 1H- and 13C-NMR t spectroscopic studies for a series of organoantimony(V) compounds, R,SbX, (R = Me, Ph, p-Tolyl; X = F, CI, Br, I). For the trimethyl- 121 antimony dihalides, two parameters of the Sb MBssbauer spectra indicated that the withdrawal of the bonding electrons from antimony atom alortg Sb-X was enhanced as the electronegativity of the halogen increased while the chemical shifts of the H- and C-NMR spectra showed that the electron population in the methyl group increased. 13 For phenyl and p-tolyl derivatives, both Mtissbauer and C-NMR data showed a trend similar to the methyl compounds, namely, as the elec­ tronegativity of the halogen increased, the absolute value of the isomer shift decreased while the electron density of the carbon atom coordinated to antimony was increased. The results suggest that the electron cloud around the antimony atom spreads, with an increase in the electronegativity of the halogen, not only toward halogen atom but also toward the plane perpendicular to the direction of halogen atoms. We also tried Hartree-Fock self-consistent-field computations to understand the electronic charge distribution in the compounds.

- 262 - Chien C. Lin Vallecitos Nuclear Center, General Electric Company Pleasanton, California 94566 U.S.A.

RADIOCHEMICAL STUDIES IN THE BWR PRIMARY COOLANT SYSTEM

•The boiling water reactor (BWR) coolant system provides a. unique process environment of high radiation fields in high purity water at elevated temperatures for radiochemical studies. This paper presents the chemistry'and steam transport behavior of two major groups of radionuclides in the BWR primary system.

The behavior of fission product iodine isotopes has been the focus of intensive investigation for some time. Both iodide (I~) (*W0%) and iodate (I0-) (^30%) have been determined in the react.gr water. The volatile iodine species carried over with steam are believed to be HIO and/or I«H_0. Laboratory experiments have clearly demonstrated that both 10. and HIO can be produced by radiolytic oxidation of I at -very low concentrations. The variation of iodine steam transport which ranges from M).2 to 2.5Z (the ratio of iodine concentration in the steam condensate to that in the reactor water) is attributed to the effect of coolant impurities, specifically copper ions, on the radiation chemistry of iodine in reactor water.

The second group of radionuclides are the water activation products, * 16 1^ mainly N(t, =7.1 sec) and N(t, = 10 min), which are produced 16 16 16 from the lo0(n,p)iDN and L 0(p,a) reactions, respectively. The chemical forms of the nitrogen isotopes have been determined and, in most cases, NO, has been found to be the major species in. reactor water and NH, is the major species in the steam condensate. Details of sampling and analytical techniques will be described in this paper. Some typical data and plausible reaction mechanisms of "hot-atoms" leading to their stable chemical forms under radiation environment will also be presented.

- 263 - Etienne ROTH (!) Michel MASSON (2) Institut de Recherche & Developpement Industriel - C.E.A. (1) CEN- Saclay DESICP, BP.N°2, 91191 - GIF 5/YVETTE FRANCE. (2) CEN FAR DERCA BP.N°6, 92226 - FQNTENAY AUX ROSES - FRANCE.

TRITIUM CHEMISTRY IN FISSION AND FUSION REACTORS.

In fission reactors tritium is generated as a ternary fission product, or by capture of a neutron by the deuterium of the moderator (abundantly when it is heavy water or on a small scale in normal water). In the first case the fate of tritium is governed by its ability to react with the fuel or to permeate through or combine with the cladding. Trying to prevent accidental releases, or to minimize normal ones, both in reactors and later in fuel reprocessing plants, is the aim of tritium chemistry studies. Investigations have been carried out on fuel claddings. The ratio of tritium trapped in zircalloy to that in uranium oxide varies greatly from fuel element to fuel element even in a single assembly. Comparisons are made with the fate of other fission products, specially gaseous ones and the role of recoil is analysed. Finally a discussion is made of extraction means suitable to keep moderators at a low level in tritium.

In fusion devices tritium will be generated in the blankets by spallation of lithium 6 or by an (n, n1 ) reaction on lithium 7. Quantitative extraction from breeding materials, solid or liquid, is.necessary and, at the same time, the concentration must be kept in the p.p.m. range (by weight).

Specific problems of, the study of generation and recovery of tritium are reviewed i.e. chemical form under which tritium is produced, mechanisms by which it may be released, parameters to consider when designing a recovery unit. Experiments and results are described showing that in tritium breeding ceramics tritiated water seems to be always at least a large fraction of the tritiated species formed and conditions governing its formation are discussed. Measurement problems are assessed and a survey is given of tritium problems in liquid metal and metal alloys.

This work was partly done as combined research project with Conservatoire National des Arts et Metiers and partly within the European Economic Community fusion technology program.

\ - 264- - H. Feuerstein, H. Grabner, J. Oschinski Abt. IT, Kernforschungszentrum Karlsruhe GmbH Postfach 3640, 7500 Karlsruhe 1, West-Germany

20 YEARS CHEMICAL AND RADIOCHEMICAL MEASUREMENT AT THE RESEARCH REACTOR FR2

The FR2 has been a D-O cooled and moderated research reactor with a thermal output of 44 MW. It was in operation from 1961 to 1981. The primary system operated at a maximum temperature of 85°C, it consisted of 230 m2 zircaloy, 100 m2 Al-99.5 and 800 m2 stainless steel. A purifi­ cation system kept the PH value at 6.8 and the electrical conductivity below 1 uS. The covergas of the reactor was helium. The deuterium concentration, measured by a new developed method, de­ creased each year by only 0.012 Mol* this was equivalent with adding about 3 kg of normal water to the coolant per year. Isotopic effects could be detected in some cases. The radiolytic decomposition of the coolant created each day about 250 1 H2, this was recombined and added to the bulk D2O. The G-value far this decomposition was about 10_3. At the beginning about 2.5x10^ Ci/year tritium were formed, approaching nearly saturation with 6.5 Ci/kg D2 at the end. Tritium caused never a serious problem. C-14 was formed mainly by the N-14(n,p)-reaction. The specific activity of carbon was constant over the years with a value of 6 mCi/g C. Carbon impurities, e.g. from resins, were always responsible for the loading of the purification system with C02- With an average loading of the resins, about 3.5 Ci C-14 were fixed in the purification system, compare with 13 mCi circulating with the 0-0 and 85 rnCi in the covergas. Since a failure of a metallic fuel element in 1963, the primary system surfaces were contaminated with 1 mg U/m2 and 1 to 10 nCi/m2 of Pu- isotopes. This contamination could be removed only with acids. After decay of the intrinsic nuclide N-16 the y-activity of the coolant was mainly F-17 (400 yCi/kg). After about 30 minutes decay time, the specific activity of Mn-56, Tc-99m, Re-188 and F-18 was in the far.ge of 10 uCi/kg. Tc and Re were found because of the frequent use of M0S2 lubricant. However the specific activity of Mo-99 was extremely low. In the primary system a remarkable 'ACET0N EFFECT' was observed. Adding only a few grams of aceton to the 30 tons of bulk D2O resulted in the increase of the el.conductivity up to 4 uS and decrease of the P^ to 4.0 There are some possible explanations, however further studies are required for final clarifications.

Distribution constants were determined for D2» N2, 02, He and fission gases. Degassing was delayed with a half live of about one day. Some chemical effects were observed at the secondary cooling system, which operated with demineral ized water. - 265 - Piroska Fodor-Csanyi, J. Kasza, L. Feher Laboratory of Nucleaj Chemistry, Eofcvos University Budapest VIII. Puskin u. 11-13. Hungary H-1088

VATER MIGRATION STUDIES IN CCKNECTION WITH RADIOACTIVE WASTE

The movement of HTO labelled water from a point source was studied in the unsaturated soil of the Plant for Processing and Storage of Radioactive Waste (puspokszilagy, Hungary) as part of migration studies on radionuclides, because the radio­ nuclides are spread as point sources in the waste. Should the geological conditions of the site be suitable, the solid waste of low activity could directly be disposed in the soil without 9Jiy reinforced concrete basins. The point source was at 2.0 m and the experiments were car- 2 ried out from 2.0 to 3*15 m under the surface level in a 1 m area. The plot was irrigated daily with *f 1 water (total 765 1 •>-'1.5 year precipitation). Soil cores were taken at every 5 cm vertically and horizontally at distances of 10, 20, 30 and ^fO cm from the point source. To characterize the water velocity, a time independent quan­ tity - migration distance divided by the amount of irrigated Water - was chosen. The maximum activities measured at the dis­ tances of 10, 20, 30 and ko cm from the point source were at about the same depth from the surface, i.e. after irrigation With 186 1 water the water velocity increased from 0.17 to 0.28 cm/1, resp., but after 76*4- 1 it was 0.11 cm/1 at every distance, fhen the water moved downwards as in a uniformly labelled layer. A mathematical model is being developed to interpret the ex­ perimental results. There is a good feasibility to bury the soil wastes of low activity directly into the soil.

- 266 - H.-H- latzel, H. Hurso, K. 3urkow, D. Leopold and 3. Plawinsky*

DETERMINATION OF EQUILIBRIUM CONSTANTS IN SOLUTION 3Y USlilG AN ANALYTICAL ULTRACENTRIFUGE

Institut fur Anorganische unc Analytiscne Chewie Freie Universitit 3erlin, D 1000 BERLIN 33, West-Geraany

It is shown how on the basis of apparent molar assses which, can be obtained by ultracentrif ugation, hydrolysis constants can be calculated. In this calculation the secondary salt effect is taken account of mathematically. The procedure is tested by means of lead perchlorate in the systan Pb(C104)2-NaC104-NaOH-H20. The knowledge of the extent of the hydrolysis of the salts of the actinides in a saturated solution is of great importance for the final deposite of radioactive waste in sodium chloride formations. For this reason the hydrolysis of U0?Clp was investigated in a saturated sodium chloride solution using the above- mentioned procedure. As a result the hydrolysis constants or the fallowing particles were obtained at 25 C:

(2x y)+ (U02)x(QH)y " x=l,y=l; x=2,y=2; x=3,y=4; x=3,y=5.

Due to the small volume required ( .2 ml) the aforesaid procedure can easily be applied to the salts of the i transuranium elements.

* Bundesanstalt fur Haterialprufung (BAM) Unter den Eichen 37 1C0C 3ERLIN 45, West-Germany

- 267 - Chr. Binder*, B. Rosel, D. Leopold and B. Plev/insky*

Institut fur Anorganische und Analytische Chemie Freie Universitat Berlin, D 1000 BERLIN 33, West-Germany

DETERMINATION OF DIFFUSION COEFFICIENTS, PARTITION COEFFICIENTS AND EXTRACTION KINETICS BY USE OF THE ANALYTICAL ULTRACENTRIFUGE

Heasuretnents of nain and cross diffusion coefficients in the Th(N03)4/HN03/H20 system have shown that the Th(M03)4 concentration gradient causes a much larger transport

of nitric acid than of Th(M03) . itself. Due to this coupling it is not very sensible to determine apparent diffusion coefficients in such a ternary system. The significance of this coupling of diffusion is shown

for the extraction of Th(H0„)4 from aqueous nitric acid• with TBP/dodacane mixtures. The relevance of these phenomena with respect to extraction kinetics will be discussed. In addition, results will be presented for the extraction

of- UOp (NO.,) ? from aqueous nitric acid solution by various mixtures of TBP/dodecane. With reference to this system the advantages and disadvantages of the various optical systams of the analytical ultracentrifuge when applied to the investigation of extraction processes will be shown. The partition coefficients show a significant time dependency. This is also caused by thermodynamic coupling,

* Bundesanstalt fur H3terialprufung (3AM) Unter den Eichen 37 D 1000 BERLIN 45, West-Germany - 268 - T.Miura*, A.Hashizume**, M.Yanaga, K.Endo, H.Nakahara and S.Ikuta Department of Chemistry, Faculty of Science, Tokyo Metropolitan Ur.iversity. Fukasawa, Setagaya, Tokyo 158, Japan *R.adiocher»i3try Laboratory, and ^"Radiation Laboratory, The Ii.stitutt: of Physical and Cherr.ical Research, Wako, Saitama 351, Japan

COMPARISON OF EXPERIMENTAL CONTACT DENSITY OF VALENCE ELECTRONS WITH AQ AND MO CALCULATIONS FGR 1?5T-=

125 Radioactive I was ion-implanted into various metal matri­ ces by seans of Electro—Magnetic Isotope Separator. The MBssbauer spectra and the internal conversion spectra for 35.46 keV Ml transi- i or tion of Te were measured. From the correlation between M8ssbauer isomer shifts, 6, and contact densities of valence electrons, p (0), 1) v we deduced following equation , p (0) = 106 + 30.36 ± 4.3[(5 - 0.30)2 + 0.069]1/2 (1) where the theoretical contact density of 4s electrons, p. (0) = 928 2) a.u. , was used. Experimental contact densities deduced from the reported isomer shifts by using eq. (1), were compared with the 2 3) results of the A0 calculations in literature ' and the M0 calcu­ lations using the computer program H0N005 in this study. The experimental contact densities for TeF-, 65.3 ± 7,4 a.u.,

TeCl., 142 i 5 a.u., and TeCI?, 127 x 6 a.u., are in good agree­ ment with the results of the M0 calculations, 65.4 a.u., 139 a.u. and 126 a.u., respectively. In addition, those values coincide with the results of the AQ calculations'for electronic configura- 3 2 2 2 2 tions of 5s5p 5d , 5s and 5s 5p, respectively. From the above comparisons, it is confirmed that TeFg is a covalent compound with an octahedral symmetry and that TeCl. and TeClo are rather ionic. These results are compatible with those results of infrared and Raman investigations. We also tried to understand the molecular structure of more complex compounds. References 1) T.Miura et al., ICAME '85 Abstract, 3.64. 2) I.M.Band and V.I.Fomichev, Atom. Data and Nucl. Data Tables. 23 (1979) 295. 3) P.H.Barrett et al., Phys. Rev., 12B (1975) 1676. .- 2€9 - S.K. Shakshooki, 0. Azabi, 5. KhaLil and J. Kowalczyk. Department of Chemistry, Al-Fateh University, and Secretariat of Scientific Research, Tripoli, Libya, SPLAJ.

MIXED INSOLUBLE ACID SALTS OF TETRAVELENT METALS - IV CRYSTALLINE MIXED ZIRCONIUM-TITANIUM PHOSPHATES

Mixed crystalline zirconium-titanium phosphates, ZrxTiyfHPO^^.i^O in the alpha crystalline form have been prepared both by the well known reflux method (1 ) and crystallization from HF solutions (2). These products wre then examined for their cheaical C&T.position, powder X-ray diffractions and thermal analysis- Exchange capacity for these ion exchangers has been evaluated by pH titration combined with radio- isotope-tracer technique for Na+, K+, Rb+, and Cs+ ions. Reflux method: Gels of known composition (Zr:Ti ratio) were refluxed in 12M H3?04 for 48, 100, 200, 300 and 500 hours. Materials obtained up to 200 hours of reflux were found to be crystalline, homogenous and without change in composition. Materials refluxed between 300-500 hours were also crystalline and homogenous but the composition changed to higher ratio of Ti. HF method: Conditions set by earlier workers (2) for the preparation of ZrP and TiP were not suitable for the best recovery of mixed phos­ phates. Conditions such as concentrations of ZrOCl2, TiCL4 and HF have been modified. The products obtained by this method are again found to be homogenous and crystalline but the composition of the product in this case changed in the favour of higher ratio of Zr in contrast to the prolonged reflux method. X-ray: The mixed ZrTiP appears to form solid solution of Zr in Ti or vice-versa. Materials with less than 50% Ti give diffractograms almost parallel with standard ZrP and materials with more than 50% Ti gave diffractograms almost parallel with standard TiP, except for the fact that the peaks are somewhat broader at the base (3)- Ion Exchange: There is not much difference in the exchange capacity for the ions in materials obtained by either method, and their average value for Na+, K"*~, Rb+, and Cs*" is found to be 3.85, 3.8, 1.7 and 0.5 respectively. It has been found that materials with 10% Ti is the most important member of this series. It gives better resolution in the separation of alkali metals. (1) A. Clearfield, Inorganic Ion Exchange Material CRC. Inc. Press, 1982. (2) G. Alberti and E. Torraca, J. Inorg. Nucl. Chem., 30, 317, 1968. (3) A. Clearfield, Ann. Rev. Mater. Sci., 14, 205, 1984.

- 270 - T-. Hashimoto, K. Yokosaka and Y. Hayashi Department of Chemistry, Faculty of Science, Niigata University, Ikarashi-Ninc-cho, Niigata 950-21, Japan

EMISSION PROPERTIES OF THERMOLUMINESENCE FROM NATURAL QUARTZ MINERALS

Quartzose extracts, from pegmatite rocks, volcanic ashes and beach sands, were exposed to Gamma-rays or X-rays upto 8.8 kGy (880krad). The irradiated sampes were observed through a thermoluminescence colour image technique (abbreviated to TLCI by the authors) using highly sensitive colour photographic system (1). Remarkably different colour images, which are readily distinguishable into red and blue TL-emitting grains on TLGI (2), were observed among the geologically different quartz specimens. The quartz sands from volcanic ash layers, containing g- quartz (mineralized at high temperature), always indicate a red TLCI, while the quartz rocks from pegmatite origin and granite strata, containing O-quartz (mineralized, at low temperature), gave a typical blue TLCI, being consistent with the well known quartz TL colour. Quartz fractions from the beach sands showed a mixture of both red and"blue TLCI, probably reflecting the respective mixtures of (5-(in their origin) and a-quartz fractions along the riverside area. The search using X-ray diffractometry and instrumental neutron-activation analysis proved that the cause of distinctly different colourations was attributable to the impurity atoms; light rare earth elements (Eu and/or Sm) bringing on red TLCI, while structural defects yielding the blue TLCI. References (1) T. Hashimoto, et al., Radioisotopes, 32, 525-532 (1983). (2) T. Hashimoto, et al., Geochem. J., in press.

- 271 - Kirsti-Liisa Sjohlom and Erkki Ilus Finnish Centre for Radiation and Nuclear Safety Helsinki,Finland

l THE ESCAPE OF "*C02 INTO THE LABORATORY AIR DURING PHYTOPLANKTON PRIMARY PRODUCTION STUDIES

Primary production of phytoplankton is commonly measured by the radiocarbon method presented by Steemann Nielsen in 1952. In that method NaH CO- is assimilated by phyto- plankton in experimental bottles. After that the water is filtrated and the activity of the phytoplankton on the filters is determined. During the filtration some of the C escapes from the water as C0?. If a fume hood is not available, contamination of the laboratory air is possible 14 In our field laboratory about 70 MBq NaH CO.is used annu­ ally, about 6 MBq at one time. The solutions are handled under a kitchen ventilator. The C0„ content of the lab­ oratory air was analysed in order to evaluate the radi­ ation exposure of the workers. Air was collectad-before each working period, during the pipetting of NaH C0_ and during the filtration of samples. Also outdoor air was collected during the filtration procedure. 14 C0_ was collected in NaOH solution, precipitated as BaCO and measured by liquid scintillation counting in a rigid gei. During the filtrations the concentration of radiocarbon in the laboratory air varied between 50 and 970 Bq m__. The intermediate content in the air was about 30 Bq m

The highest CO- concentration in air was 1/3000 of the DAC given in ICRP 30. Furthermore, because the workers spend only a short time weekly in the laboratory the radi­ ation exposure caused by inhalation of C0„ from the lab­ oratory air is insignificant.

- 272 - •Huang, Y.P., Luo. S.D.. Shi. W.Y., Chen, 2. Department of Oceanography, Xiames. University, Xian»en. China

RADIOCHEMICAL STUDIES ON EJEEP-SEA MANGANESE NODULES

A. simple anion-exchange.technique and alpha spectrometry have been used to determine the activities of U and Th isotopes in deep-sea manganese nodules collected from the Northern Mid-Pacific Ocean floor. The results show that:

(1) In the deep-sea manganese nodules disequilibrium exists between natural radioactive nuclides because of the difference in geochemi- cal behaviors of U and Th. The Th/U ratios are higher in manganese nodules than in the earth's crust, indicative of enrichment of Th in manganese nodules compared to U. Pa and Th in the surface layers of manganese nodules are 2*-3 orders of magnitude as high as their parents and decrease exponentially with the depth toward its cores.

(2) The growth rates of the manganese nodules which are estimated ^ ^ • „,_ 230.™. 230^_ ,232,™ . 231„ , on the basis ofr the Th , Th / Th and Pa dat t a range , ex ex ex from 0.8 to 7.4 mm/10 yrs. depending on their N4i and Fe contents and the classification of the sediments underlying them. The larger the Mn/Fe ratios of the manganese nodules, the higher their growth rates.And the growth rates of the manganese nodules overlying the silica-calcium ooze are higher than those overlying the red-clay sediments.

(3) The turnover time of a manganese nodule from Site ML. estimated 230 232 2^0 231 JU J1 from the { Th /"*Th)n. ( Th ),. and ( Pa ). data is 11.2, 4 13.7, 9..83 (10 yrs), respectively, in agreement with each other.

^ 273 - -citute of Oceanology, Academia Sinica Liu Zhihe Shandong Institute of Medical Science

THE DISTRIBUTIONS AND GEOCHEMICAL STUDIES OF U,Th,Ra, 40K IN SEDIMENTS OF CHINA SEA*AND ADJACENT SEA

The determinations and geochc.ni ral studies of "0 , Th , 40 • Ra, K in surtace sediments of China Sea and adjacent sea, including Okinowa trough and the downstream and estuary of the Yellow river and the Yangzijiang river as veil as Zhujiang river and Rongjiang river, were carried out with 8180-4K multichannel Ge(Li)T Spectro­ meter in 1981-1985. The mean values of U, Ra. Th, 40K are :ibout 2.11ppm, 7.67x10 g/g, 11-OOppm, 2.33ppm respectively in China Sea and Okinowa Trough,the estuary of the Yangzijiang river and Yellow river. The distributions of four isotopes are uniform in the above zone. The contents of U and Th in sediments are 1-4 times higher than that of the above zone in Zhujiang river, Rongjiang river and Fujian coast. It is related to granite and radioactive ore which are present on uprivei or adjacent mountains.

40 The distributions of U, Th, Ra, K are related to their physical-chemical property, redox state, biotic activa­ tion and grain size of the sediments and geological type.

There are diluted and enriched phenomena for U and Th in mixed zone of river and sea waters.

The Ratios and variations of Th/U and Ra/U in sediments were also studied.

- 274 - Michiko ABE and Siro ABE National Institute of Radiological Sciences 9-1, Anagawa-4-chome, Chiba-shi 260 JAPAN

PHYSICAL AND CHEMICAL BEHAVIOR OF BE IN THE ATMOSPHERE AT CHIBA

It is very useful in various fields such as geo-science and health physics to investigate physical and chemical behavior of stable or radioactive substances in?the atmosphere. Physical and chemical behavior of Be in the atmosphere at Chiba are studied here. 7 The particle size distribution of Be in the air was determined using an Andersen high volume sampler with five stages. The flow rate was 566 1 min-1 . Solubility test was carried as follows: After vigorous shaking the dust sample and reagent solution, the soluble part is separated from the insoluble part by filtration. Reagents used is 6N HCl, 6N HNO3, water and ethyl alcohol. All samples were measured using a Ge(Li) gamma-ray spectrometer. A part of results obtatained is shown in Fig.l. As seen in the figure, 60 to 80% of Be in the air at Chiba is contained in particles less than 1.1 ^im during the observa­ tion period, and the tendency seems not to vary greatly with the season. Average size diameter of 'Be is determined as AMAD. The value of AMAD at Chiba varies 0.6 4 to 0.80/im. From solubility test by several reaaents. Be in the air at Chiba is soluble in 6N HCl and 6H HNO3, and almost insoluble in water and ethyl alcohol. From comparison of solubilities of Be in the air with the solubility data of beryllium compounds, it might be suggested that ?Be would be contained in the air at Chiba in the chemical form of beryllium oxide.

0.80

0.60 AMAD: Q VW\^ Activity Median Aerodynamic Diameter < •\ 3 o..4 0

80 •vA^yyy^ 60 5 O.l • • 1.1 - 2.0 °—° 2.0 - 3.3 40 » ° 3.3 - 7.0 •I • >T.O

tw«« m m*4»4 «*.

-•.•'.'.'" A « • 4 . . .>>>0»»«JJ»P1«A«I1JJJA 'S3'B4 'as

Fig.l. Time variation of particle size distribution

and AMAD r>f 7ga in t-ho aii- a+- Phiha Yuko SaitOy Midori Chigira and Kan Kimura. College of Science and Engineering, Aoyaraa Gakuin Univ 6-16-1 Chitosedai, Setagaya-ku, Tokyo, Japan.

90SR and 157CS IN TREE RINGS OF THE JAPANESE CEDAR, CR YPTO HEP T A JA TO MICA.

The wood sainDies were the Jar:.u-st _^J ^ , ^vDioineria iaponica., collected from central part of Japan. They were healthy about 7C-year-:old. The wood was cut into 5 annual ring each and analyzed. After ashing below 40O*C, ^ Cs in the ash was directly measured by on Nal(Tl) scintillation counter. "~Sr was precipitated with carrier by adding ammonium carbonate and then on Y milked was measured v/ith a low background GK counter, As a result., the maximum 90S r concentration was approximately 40 pCi/kg air-dry in sapv/ood at 1956-61, an 1966-71 and 1976-82 AD rings. - Sr concentration in heartwood was clearly lower than in sapwood. Stable strontium concentration was rather constant from the center to bark, 4--1C ppm. Kcvcver ? ' C~ concentration in heartwood was 8-14 pCi/kg air-dry, higher than in sapwood, 2-8 pCi/kg air-dry, and similar trend was found for stable cesium. Masanobu WATABABE*, Izumi MOTOYAMA**, and Hirotoshi SANO* •Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Fukasawar Setagaya, Tokyo 158 **Department of Chemistry, Faculty of Engineering, Kanagawa University, Rokkakubashi, Yokohama 221 Japan

MOSSBAUER SPECTROSCOPIC STUDIES OF METAL HALIDE ADDUCTS WITH F5RROCENYLRUTHENOCENE AND RELATED COMPOUNDS

Although ferrocene gives only unstable adducts with certain metal acids, ruthenocene gives stable adducts with them. The longer separation between the cyclopentadienyl rings in ruthenocene than that in ferrocene provides a good explanation for the fact that ruthenocene can donate •the e_. electrons of the ruthenium atom to a Lewis acid giving stable coodination compounds. It was found in our investigations that there are two way to obtain 'metal' adducts in which the e-. electrons are donated to an acid. 2g First of them is [2]ferrocenophanes. The authors reported the electronic state of these adducts. The other category is binuclear metallocenes. The present paper describes the results of* the ' Sn- and Fe-Mossbauer spectroscopic studies of mercury(II) and tin(IV) chloride adducts with binuclear metallocenec. Biferrocene, ferrocenylruthenocene and biruthenocene react with HgCl- and SnCl. giving more stable adducts than the adducts of ferrocene and ruthenocene. Large quadrupole splitting values (2.93 mm s for biferrocene(HgCl ),, 2.99 -1 ? mm s for f errocenylruthenocene (HgCl?),-, both at 78 K) in 57 ^ 3 Fe-Mossbauer spectroscopy, suggest the presence of a 119 direct interaction between Fe-Hg atoms. Sn-Mdssbauer spectroscopy indicates the presence of organotin(IV) species

(isomer shift: 2.22 mm s for ferrocenylruthenocene(SnCl^)3-

(HoO)- and 2.29 mm s~ for biruthenocene (SnCl4) , (H20) 2)', suggesting the direct chemical bonding between Ru-Sn atoms. The stability of their adducts can be explained by assuming chelating effects of the metal-metal atoms in binuclear metallocenes. - 277 - K. H e i n zyi n g e r Max-Pi anfe.k-I.nsti tut flir themie (Qtto-Hahn-Institut), Mainz, Federal Republic of Germany

A MOLECULAR DYNAMICS SIMULATION OF LIQUID T^O.

\

The cl ass i c a 1 e q u ation s of motio n are solved numeri- cally for 21 6 TgO mol ecule s in time steps of 2-10-16 s. The pa rticle s are enc 1 osed in a box with a sidelength corres pondin g to the densi ty of 1iq uid water and perio- die bo undary conditio ns ar e applied . The simulation ex- tended over 5 ps. The resu lting kno wledge of position and v e locity as well as or ientation and angular velo- city a s a fu nction of time means a complete description 'of the syste m in a cl a s s i ca l sense. Therefore, the t-hermo- dynami c , str uctural a s wel 1 as dyna mical properties of TgO ca n be c al culated wi th the help of statistical me- chanic s . In this way mol ec ular dyna mics simulations can predic t prop erties wh i ch c annot or not directly be measur ed and can expl a in m acroscopi cally measured pro- p e r t i es on a molecul a r 1 eve l [1]. In this presentation ma inly dyna mical properties of 1 i q u i d T2O are reported, e .g. the s elf-diffus ion co- e f f i c ient , reorientational motions, spectral densities of h i ndere d translations, 1ibration s and internal vi- b r a t i 0ns . All these proper ties are derived from the simula tion with the help 0 f various autocorrelation functi ons. The data are co mpared wi th the results of a simu lation of liquid H 2 0

Reference: [1] K. Heinzinger, Physica 131B, 196 (1985).

- 278 - * * ** C- Ferradini , D. Jore and L.K. Patterson * Laboratoire de Chimie Physique, University Rene Descartes, 45 ru*? des Saints Peres, 75270 Paris Cedex 06. «-* Radiation Laboratory, University of Notre Dame, Indiana, USA. IONIZING RADIATIONS AS A TOOL FOR STUDY ABOUT MECHANISMS OF BIOLOGICAL INTEREST : APPLI­ CATION TO VITAMIN C IN ALCOHOLIC MEDIUM.

y radiolysis of ethanol using a60 Co source provides homogeneous solutions of HjC-CH-OH (R-) radicals with a yield G„.sja.8 molec./iOOeV and e" , (G - a 1.7 molec/100 ev). solv Under air, the following reactions occur : e"solv *°2—>< -911 CD R* + 02 »R02 (ki = U.6 x NT mol -l.s~' ) Performing y irradiations of aerated ethanolic solutions of a solute (S) allows therefore to observe the reaction of S with the peroxy radical RO2 and possibly -with the superoxide anion O2". It is assumed that the antioxidant properties of vitamin E are related to the scavenging of lipid peroxy radicals, well known as peroxidation chain carriers. The activity of atocopherol (aTH), the most important component of vitamin E, was thus studied at this point of view. The results analysis leads to admit that aTH is oxidised by R02 giving aT * radical according to (2) , 1 1 (2)aTH + RO2—raT' • ROOH (k2 -=9.1 x ld mar .l.s" ). (02* does not react with aTH). aT' disappears by a second oxidation by RO2 (3) and/or disproportionation (4) 1 (3) aT' + RO" — -> aT* + ROOH (k ^ 2.5 x 10 mol" .l.s" ) U) aT' +aT" -* aT* + aTH (k = 1 x 104 mol"'l.s"1) 6 aT reacts stolchlometrlcally with ethanol and provides the observed product «T0C_H Wmax = 242 nm, e = 8600 mol" .l.cm ).

Pulse radiolysis of O2 and N2 saturated ethanolic solutions of aTH was performed with high doses (230 Gy) and low doses (5 Gy). Two different radicals were observed according to the conditions. T

HO

16™33

P. 16"33

420 nm netic scheme is proposed for both cases. - 279 Wang, R.S., Chen, J.X. , Liu, 2.W. Department of Chemical Engineering,, Tianjin University, Tianj in, China

THE ADSORPTION BEHAVIOR OF MICROAMOUNT OF RADIUM ON INORGANIC TON EXCHANGERS

The use of inorganic sorbents appears co'be especially promising for the adsorption of radium. This, paper describes results of tests on removing radium from simulated liquors containing 5037 pCi of 226R& per litre by inorganic ion exchangers. A number of materials, including barite, fresh salts, synthetic zeolites etc., are found to be efficient radium adsorbents.

The equation used to calculate the distribution coefficent of radium is

v _ Ao-A V d K<* A~ ' ~W~ where Ao and A are the counts of solutions before and after equilibrium respectivelyj W is the weight in g of the adsorbent taken for equilibrium-, V is the volume in ml of the original solution and d is its density. Under given conditions, the K^ of radium obtained are as follows: barite celestite ilmenite BaS04 Ba3(PO/j)2 Nb205 2955 2420 1390 4350 5775 3325

La203 Ce203 Er203 Ho203 MS(Ca 5A) Zerolit S/F 4150 4436 4682 4554 2895 2920 The adsorption mechanism for microamount radium on interface and interphase has been discussed. The barite and barium salts possess a specific selectivity for radium in the aqueous solution with multicomponent composition.

- 280 - Jerzy KROH Institute of Radiation Chemistry Technical University of Lodz, V/roblewskiego 15, Poland

EARLY STAGES CF ELECTRON INTERACTION WITH MATTER - - MECHANISM AND KINETICS

Most conveniently early stages of electron processes inay be investigated "oy pulse radiolysis or/and at very low temperatures. The examples of such investigations are given in respect to alcohol and aqueous glasses at temperatures down to 4 K. Mechanism of electron localisation is discussed with special attention paid to electron capture via multiphonon emission. Theoretical calculations based on trap relaxation model are compared with experimental data . Kinetics of electron decay is interpreted in the frame of quantum mechanical tunnelling and advanced CTRW /continuous time random walk/ model with time dependent rate constant. The latter model has been successfully applied in this laboratory to explain kinetics not only of e7 decay but also for H atoms, OH radicals and even polymeric macroradicals.

- 281 - M.M.BHUTANI DeDartment of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi-110016 (India)

ON THE FEASIBILITY OF CONCENTRATING MINUTE AMOUNTS OF CERTAIN IONIC SPECIES BY THE ADSCRPTIC45 TBCKHIQUE-A RADIOTRACER STUDY

ABSTRACT

Based on the scientific study of deposition of certain radioactive ionic species( e.g.Cr-51,P-32, Mo-99, W-185, Co-60 and Zn-55), on ignited microcrystalline sulphates of lead, barium and strontium alongwith the subsequent elution. it is possible to develop a new experimental procedure for concentration of aqueous extracts of microgram quantities of these ionic species. Feasibility of the procedure has been studied radiotnetrically on the basis of systematic examination of working conditions e.g. carrying efficiency as a function of pH of aqueous medium, lattice/nonlattice ionic concentration, amount of carrier, carrying capacity of the carrier and extraction of activity adsorbed under the suitable experimental conditions. In principle, the procedure consists of 2 stages; first, the radioactive tracer species in dilute aqueous solution is carried under specified experimental conditions on a small quantity of ignited selected carriers;secondly, the carried activity after washing can be leached back appreciably in minimal amounts of water of specified activity.

- 282 - M. M. BHUTAN I Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Deihi-110015

SORPTION BEHAVIOUR OF RADIOACTIVE CHROMATS AND PHOSPHATE SPECIES ON CERTAIN MICROCRYSTALLTNE SULPHATES 3Y THE RADIOTRACER TECHNIQUE ABSTRACT

The influence of pK and that of the added lattice as well as certain ncnlattice ions has been studied radiochemical ly, towards the instantaneous deposition of 51_ 2- 32_ 3- radioactave "^CrO end ^GA tracer species on ignited lead sulphate, barium sulphate and strontium sulphate. An increase in the sorption is observed with the rise in pH and concentration of lattice cations. However,nonlattice 2+ 2+ cations e.g. Ba and Sr ions, with similar charge and ionic dimensions, show an abnormal influence on the surface of lead sulphate and Sr + ions on the surface of barium sulphate in esse c£ chrocr.atc i

RECENT DEVELOPMENTS IN THE USE OF NUCLEAR TRACK FILTERS FOR APPLIED PURPOSES

The production of Nuclear Track Filters using heavy ions from the UNILAC, Gesellschaft fiir Schwerionenforschung, Darmstadt, Fed. Rep- of Germany, is well known. We used mica as base-material and developed two new fields of application: 1. The separation of two different liquid phases (emulsions) using mica microfilters with large holes (4-8um). Here we report on first experiments to separate a well-mixed emulsion consisting of TBP ((tri-butyl-phosphate) in kerosine plus dilute nitric acid. Further extended applications will be discussed. 2. The possible separation of different gases in hyperfine (<5nm) mica tracks: Here we report on our attempts to produce hyperfine mica tracks in the order of approximately 5nm. The gas throughput of different gases through such filters will be described, as well as the discussion of some further applications.

- 284 - Kliassoedova T.G., Ikonnikov M.J., Zagorets ?.A. D.I.Mer.deleev Institut of Chemical Technology, Moscow, USSR Sri.V2XT EXTRACTION OF Sr2+ AND Cs+ WITH CROWS STHSR

One of important directions of the nodern radiochemistry is development of solvent extraction DroceBoes for the treatment of irradiated fuel dements (1). Th.p-re are some problems in extrac­ tion technology, which must be solved, in particularly selective removing of two radionuclides, possesing long half-lives - Sr and Cs - from the asid waste C2). The solution of this task would allow to make the solvent extraction process more hasard- less and economic. Crown ethers, having high radiolytic stabi­ lity (3) could be sutable selective extractants. The aim of present work is to determine the distribution coefficients (D) of Sr2+ and Cs+ from HNO, solutions by dicyclo- hexot8crown6 (DCH18C6) and dicyclohexo24crown8 (DCH24C8) in chlororganic solvents. It is shown, that the distribution coefficients depend on the ratio of concentrations crown eter/extractable metal. The high values of D (~8 for SrCr) have been achieved in case of 3-4 exess of crown ether. The increasing of the cavity of crown ether from DCH18C6 to DGH24CB causes the raising of Cs+ distri­ bution coefficients *-in 3. Literature: 1. Lascorin et al.Radiochimiya, 1985, v.27, ff 2, 157-170. 2. Gerow I.E., Davis M.ff. Sep.Science Technol., 1979, 14(5), 395-414. 3. Miasaoedova T.G. et al.Chimiya visokih energy, 1984, v.18, N 2, 110-113.

- 285 - Navratil Oldrich, Herrmann Eckhard University Purkyne, 611 37 Brno, Czechoslovakia Technical University, 8027 Dresden, German Democratic Republic HBST PHOSPHORUS CONTAINING EXTSAGTAJSTS FOR SEPARATION OP METALS

The following compounds: ((RO^PO^KK v/ith R = Ph Q) ,

(PhO)2P(S)-NH-P(0)(OPh)2 (2), (Ph0)2P(S)-lIH-P(S)(0Ph)2 (3.), (PhO)2KO)-NH-C(0)Pli (4), (PhC(0))2lTH (3.), (PhC(0))2CH2 (6), (PhO)2PCO)-CH2-C(0)Ph (JJ and ((PhO)2P0)2CH2 (8) have been used for extraction of metal ions. These compounds are Brondsted acids, HA, and are supposed to be able to form neutral chelates JIA_. The acidity of HA decreases in the sequence 1^ £> 5_~ £ > I > 8. The most powerfull extraction agent for trivalent ions of rare earth and actinide elements is 2_. The extraction is described by the equation

B£) + 3 ^Corg) — **3(org) + 3 H(w) at low concentrations of KA in benzene, respectively. Ths metal ions are coordinated to the extractant through the phosphoryl oxygen atoms in the ligand. If phenyl groups in 1_ are substituted by octyl groups the distribution ratios D drop by about two orders of magnitude. Whereas the hard cations Sc^1+ , Ln 3+ and Hf4^+ are extracted excel- + 2— 3+ lently by 1^ the softer ions Ag , Hg and Au^ are not extracted. The opposite behaviour was observed for the sulfur containing extractants 2: and 3_* Here the first group of elements is not extracted while the extractability of the second group is very good. The best extraction of Ag , Hg2+ and Au^+ was observed with 2. The extraction occurs via an ion exchange mechanismus.

- 286 - Chen Jinxing, Lin Shaoaeng,.Zhang Pingqing and Chen Qiaoyun

Third Istitute of Oceanography,National Bureau of Oceanography, Xiamen. China

THE APPLICATION OF NATURAL RADIOTRACER TO STUDY THE TRANSPORTATIVE REGULARITY OF THE SILTS IN JIULONG RIVER

By determining the horizontal distribution of gross fi in sediments of the Xiamen sea area, it is understood that the most silts from the Jiulong River move to the outsea along the main current direction of the Jiulong River through the outside Xiamen Harbour. Only a few of the silts enter west Xiamen Harbour(i.e. main channel) with the rising tide and residual current. The great part of the silts stops in the west-section of the west harbour, without entering the east-section of the west harbour, which has affected on the channel of west-section, but not affected on the channel of east- section. Then, there is part of silts in the west Xiamen Harbour enters Jiulong River with ebb tide, and enters into outsea the last. Then, the silts which have entered into the Jiulong River from the west Xiamen Harbour is more 10% than the silts which have entered into the west Xiamen Harbour. So, we consiaered that the main reason of silt up in the west Xiarrert Hart-cur is ero€^

- 287 - Zhong.G.T., Hong.J.F., Chen,Z.A- Department of Chemistry, Zhong Shang University, Gusng 'Sftou , China

A PRINCIPLE OF ELEMENT DILUTION

Isotope dilution is well known, but no intormation on element dilution has appeared in literature.

The present paper proposes that two elements can be diluted by each other in case the following require­ ments are met: (1) The conditional equilibrium cons­ tants of the two elements K., K_ in a chemical reac- A B tion are similar-; (2).The produced compound of the element to be diluted supplies a measurable and cha­ racteristic physical property; (3) The reaction per­ centage of the agent p(s) is a constant when the concentration of an element changes and the amount of that agent is substoichiometrical. On the basis of these requirements , the following formulas, which represent the principle of element dilution, have been derived:

1 f =1 - (f-l)cjj P(S) A (nC° Ao)~ (2) where: C°. C° and C° are the original concentrations A B R K of element .M , M and agent HR respectively;J = A/KB- A , A are the characteristic physical parameters of produced compound of element M. in the critical solution and the dilution solution respectively; n is the valence of element M, or M_. A B The formulas (1), (2) were "tested by the substoichiome- tric extraction of copper and lead by diethyldithio- carbamate in carbon tetrachloride.

- 288 - H. Feuerstein, J. Oschinski Abt. IT, Kernforschungszentrum Karlsruhe GmbH Postfach 3640, 75C0 Karlsruhe 1, West-Germany

BEHAVIOUR OF U02 AND FISSIUM IN SODIUM VAPOR ATMOSPHERE AT TEMPERATURES UP TO 2850 °C.

An experimental technique was developed to study the behaviour of UO2 and FISSIUM in a sodium vapor atmosphere at-temperatures up to 2850 °C. The samples are in thoria crucibles in a inductively heated tungsten receptor. Sodium vapor transports evaporating substances into condenser and filter lines. Density and open pore volume .were not changed during the experiments, probably because of compensating effects of densification and creating of new pores. Evaporation rates for UO2 were determined. Values up to 0.1 mg/cm2. s were found for a temperature of 2800 oc. The values are in agreement with a model given by Aitken. The evaporation starts probably at grain boundaries. The remaining surface is composed of small spheres, sometimes agglomerates are growing on the surface. The new created surface is very brittle. "Thermal reaction' of the VQ^ takes ^lac& at high temperatures, a metallic uranium phase is formed. The end-composition was found to be UO, gg, in agreement with estimations from thermodynamical considerations. At high temperatures (2600 to 2800 OC) U0? crystals were formed on all surfaces inside of the thoria crucible. Different well shaped forms were found. Erosion of the crystals creates new sometimes curious forms. All. the crystals and erosion products were UO2.

- 289 - J^V. Evans, P^L. -Brown and G. Sinclair Australian Atomic Energy Commission, Research Establishment, Private Mail Bag, Sutherland, NSV 2232, Australia

GEOCHEMISTRY OF URANIUM AND DAUGHTERS IN TAILINGS FROM THE MILLING OF URANIUM ORES.

Selective chemical leaching is being used to investigate, the phase distribution of uranium and,|rs more important long-lived daughter produces, "" Th, Sa arte *" ?b »-ithin solid tailings arising fro— the milling of Australian uranium ores. A knowledge of the solid state speciation and ponding of these radionuclides within the raineralogically and chemically heterogeneous tailings matrix is important to the prediction of the likely long-term behaviour and environmental impact of the waste.

A five-step sequential extraction procedure was used to fractionate the following phases (the extractant is given in parentheses): (a) water soluble (water); (b) ion exchangeable.(0.IM NaCl); (c) amorphous iron and manganese (Tamm's solution); (d) crystalline iron (Chester-Hughes' reagent); and (e) alkaline-earth sulphates (O.llM Na7 EDTA). The mine tailing samples used in the procedure were taken before and after lime neutralisation and each chemical extractant was analysed for iron, manganese, calcium, barium, aluminium, sulphate, thorium-230, radium-226, lead-210,- and uranium. The initial mine tailings and the remaining residue were also analysed for these elements/isotopes.

Results from the extraction procedure demonstrated that a precision of 57, (RSD) and a mass balance of 10?. deviation could be obtained for each element studied. Analysis of the extraction solutions reveal that aluminium, barium, iron, and thorium-230 are relatively inert with greater than 807, remaining in the extracted residue, which indicates that they are tightly bound by clay, sand and other mineral lattices. The remaining elements are less inert to varying degrees, their speciation depending significantly on the type of tailing analysed (acid or lime neutralised) and the chemical oxidant used in the milling process (pyrolusite or Caro's Acid).

- 290 - M. Put, P.M. Henrion and Yan Jiade* Studiecencma vcor kerr.enercie/ Centre d*etudes nucleaire SCK/CEM, Mol

SOKE ASPECTS OF HADIOLYSIS IN THE BOOM CLAY FORMATION

The purpose of this paper is to present the SCK/CEN approach to the assessment, of radiolysis in the Boom "clay formation that would result from the presence of a repository of high level waste. Radiolysis may indeed constitute a hazard because the water content of a saturated clay is high (+17 %), and because the consumption of oxidizing radicals in a very reducing environment increases the yield in molecular hydrogen.

The study includes : - the modelling of the migration of the radionuclides, simulating by a rectangular bar (0.5x0.5 m) the radioactive source which consists of a long stack of containers ,- - the evaluation of the resulting irradiation dose-rate space-time distribution and of the integrated local radiation energy dose. The 3 contribution to the energy was found to be of minor importance ; - the assessment of the maximum hydrogen production and the corresponding degree of oxidation of the clay ; - the experimental determination of a ar.c 7 ridiolytic effects in Boom clay samples. A new method of determining hydrogen yields, presently under development, is described. The purpose of these measurements is to verify if conditions theoretically- favourable to radicals recombination do indeed develop, bringing the hydrogen production back to levels substantially lower than those envisaged in the conservative assessment.

Changes taking place in the composition of the pool of exchangeable cations, in the molecular size and concentration of soluble humic molecules (the latter forming very stable complexes -with the actinices and Tc) and in the values of sorption coefficients of Pu, Eu (Am) and Tc are examined.

The distinction between near-field and far-field is drawn and the factors that determined this distinction are pointed out. Finally the role of the engineered barrier is discussed in terms of radiolytic quantities. By absorbing the burden of the intense period of a, 5 radiation the engineered barrier allows the formation to play its true role of geologic-time barrier.

* Institute of Atomic Energy. People's Republic of China - 291 - Yang Wen-Xiang, R. Subramonia Iyer and F. Sherwood Rowland Department of Chemistry, University of California Irvine, California 92717 , U.S.A.

RADIOACTIVE TRACER STUDY OF THE REACTION OF HO WITH 14CS- IN THE PRESENCE OF O

The rapid disappearance of CS2 in the free troposphere indicates the existence of one or more rapid oxidation pathways under natural atmospheric conditions. The attack of HO upon CS2 in the absence of -15 02 is a very solw reaction, with a rate constant at 298 K of < 10 - cm molecule s~ . On the other, hand, removal of CS2 by HO in the presence of 02 has been previously reported to occur with rates as high 3 1 as 10~ cm molecule" s .with OCS and S02 as the observed products. 14 We have measured the rate of reaction of HO with CS2 through the photolysis of HO at 302 ranan d 298 K. The reactions have been studied at one atmosphere total pressure in mixtures containing 0.8 torr CS2 14 (+ CS2), 2.0 torr H202„ 1.5 torr C3H8, 0-250 torr 02 and 500-760 torr

N2. The radioactive products have been analyzed by radib gas chromato­ graphy, and the total exposure to HO has been assayed through the quantitative disappearance' of C3H0 together with its known rate constant for reaction with HO.

Our experiments have shown 014CS and 14C0 as the major porducts form 14 1 the oxidative decomposition of CS2, with smaller yields of C02. 14 The overall rate constant for the removal of CS2 is calculated to be 6.7xl0-1 cm molecule s at 20 torr 0_, increasing to 3.4x10 cm -1 _1 1 molecule s at 250 torr 02. The yields of O C3 increased steadily with increasing partial pressure of O2; the yields of CO and 14C02 also increased with pressure to 70 torr 02 and then leveled off. The rate constants vs. 02 pressure found in this study are in general agreement with the recent FTIR results of Barnes et al. The decomposition of CS2 by HO in the presence of 02 is consistent with the proposed mechanism involving addition to form the intermediate HOCS2# ssid then competition between its reverse decomposition back to HO and CS2 and its forward reaction with 02 to form products. The observation of significant l4 yields of CO and C02 in all experiments suggests either that the H0CS2 intermediate can react with 02 by more than one mechanistic pathway, or that other 02-dependent reactions can occur during photolysis at 254nm. 14 14 Preliminary experiments indicate the same three products (O CS, CO and 14 C02) in roughly similar yields when the experiments are repeated using ultraviolet light at 254 ran.

- 292 - Hwei-Ru Tsou*. Zareen H. Ahmed, Ruth Fiala and Kilon W- BullocTt American Cyanamid Company» Agricultural Sesearcfe Division, P.O. Box 400, Princeton, New Jersey 08540, U.S.A.

THE USE OF 180 and 13C LABELING IN STUDIES OF THE ORIGIN OF OXYGEN ATOMS IN A NOVEL HACROLIDE ANTIBIOTIC LL-F28249

A 16-membered macrolide LL-F28249 was discovered as an endectocide produced by Streptomyces cyaneRriseus ssp. noncyanogenus. It is derived from 6 propionate units, 7 acetate units and 1 isobutyrate unit. We have incorporated

[1- C, 0 Jacetate and [1- C, 0 ]propionate separately in the fermentation culture and the resulting doubly 13 labeled macrolide samples were analyzed by C NMR. Out of a total of eight oxygen atoms in the macrolide, three and four oxygen atoms originate from propionate and acetate respectively. The origin of the remaining one oxygen atom was 13 18 determined by incorporating [2- C]acetate and 0 gas into the fermentation culture in a specially designed 13 fermentor. Both C NMR and MS spectra of the isolated macrolide prove that this oxygen atom originates from oxygen gas.

*The present address: Medical Research Division, Lederle Laboratories, American Cyanamid Company, Pearl River, New York 10965, U.S.A.

-293 - AUTHOR INDEX

Aagaard, P. ; 52 Bronikowski. M. : 25 Aaltonen, J. 221 Brown, P.L. : 290 Aarkrog, A. : 253 Bujak. A. : 38 ABE, Michiko : 275 Bullock, M..W. : 293 ABE. Siro 275 Burkow, K. : 267 Abeysekera b.f. 220 ButLe, P.P. : 24 Ache, H.J. : 149 2 17 Butzev, V.S. : 25 Ackerhalt, R.E. 2 36 Calne, D.B. : 209 Adachi, T-. - 56. 95 , 128 Cao. G.Y. ( T&'H^J ) : 233 Adam, M.J. : 209 Carmony, D.D. : 38 Adloff, J.P 21 Casarci, M. : 89 Ahmed, Z.H. 293 Cen. Y.H. ( -£iE# ) 192 Ai. H.T. (1£fc"k3> : 123 Chai. C.F. ( #£# ) : 14 Albinsson, Y. : 135 173 Aleklett, K. : 25, 34, 52 Chang, C.Z. ( JR#.£ 130 Alstad, J. : 35 Chang, J.P. ( Jfc-fctt 238 Ambe, S. : 235 Chang, J.X. < *•£# 192 Ames, F. : 152 Chasteler. B. : 36 Angelini G. : 49 Chatt, A. : 143 Aota, N. : 183 Chen B.K : 178 Aras, G. : 208 Chen B.R . (ft#fc) :161,2 Asher J. : 31 Chen B.Z . : 79 Azabi 0. : 270 Chen ( fc & ) : 180 Baba, Hiroshi 50 Chen F . ( [$Mft ) 74 Bachmann, K : 259 Chen x. (»*# ) 280 Bai, L.-Q. : 222 Chen 287 Bao, B R. ( il.ib%. ) : 125 Chen K.J (mx) 202 126, \ fc^fc ) 105 136 Chen L.Q (&&& > Bao. Y .W. (ffttfZ) : 231 Chen M.A. 191 Bao, Z 22 <»#*) 179 • Y. <-&&# ) : Chen M.X. i jmf)) Baro, G.B. : 189 Chen 287 Q.Y. ( fr*5ir ) 123 Barreta, L.G. : 64 Chen S ( ft # ) : Bautz, H. : 96 Chen S, Z . ( J* jft# ) 229 Bayat, I. : 131 Chen X, G. ($££) 106 Becker, R. : 96 Chen Y. D. ( #-£* ) 82 Bellido, A.V. : 64 Chen Y. H . ( ft.Kft ) 260 Bestanpouri, A. : 25 2 Chen Y. Z. ( «LR«f ) 69 Bhutani, M.M. : 282 , 283 Chen Z. ( * X ) : 273 Bi , S, L. ( *£%& ) :15 1 Chen Z. : 26 Bian. Z.S. ( |"l;J- ) : 186 Chen Z. A.. ( ft-?*p ) : 288 Bierer, D.E 218 Chen Z.D. ( ft*Xt ) : 121 Bievre, P.De 150 Chen W.J. ( frXfc ) : 113 Billings, JJ : 241 Cheng, Y.D : 136 Binder, Chr. : 286 Chi, L.Y. (#&in:> 233 Bleyl, H.-J. : 62 Chida, F. : 169 Bogancs, J. : 205 Chigira, M. : 276 Bogdanov, R V. : 42 Chin, C.T. : 83 Bonn, J. 152 Chitwood, C.B. : 2 Boothe, T : 217 Chopping. R. : 104 Bowersox, D.F. : 73 , 120 Christensen, D.C. 73 Brandt, R : 25. 159 , 284 Chui, J. ( & ^ ) 74 Brillard, L. : 116

- 294 - Chung. Y.H. : 38 Endo. K. : 46. 169. 175, Cipriani. C. : 212 196. 255. 262 Clauss, H. : 155 Erbay, G. : 208 Cleveland, J-M. : 59 Erlandsson. B. : 166 Corte. F.D. : 148 Ertel, D. : 90 Cristalli, M. : 212 Evans, J.V. : 216 290 Dahlgaard, H. : 253 Fan. M.Y.( 5&ffn£ ) : 179 Damen, R 150 Fan , W. ( 5c & ) : 41, 261 Dange, S P. : 24, 48 Fan, X.H. ( S££* ) : 93 Dardenne C. : 145 Fan, Y.F. : 69 Das. N.R : 171 Fang. Y.B - <£££) : 44 Das, S.K : 24 Fedoroff, M. : 127 Datta, T : 24. 48 Feher : 266 D'Auria, J. : 37 Feige , G. : 25. 159 David, F. : 65 Feng. J. (# £) ; -249 De Goeij, J.J.M. : 242 Feng. X.Z. (i94S#) 67. 97, Delmas, R . : 145 98. 99. 202. 132 De Paepe, P. : 184 Ferradini, 279 Dersch. G . : 25, 159 Feuerstein H. 256, 265 De Rudder , J. : 184 289 Deschamps , N. : 145 Fiala, R. : 293 Deshmukh, S.H. : 24 Fields, D.J. : 26 DeSilva, K.N. : 143 Fife, K.W. 73, 120 Ding, R.Q. (T» ) : 231 Finn. R.D. 217 Ding, W.D. ( TX#. ) : 238 Flambard, A R. : 58 Ding, Y.W. ( Ttf* ) : 100 Flanagan, R J. : 247 Dondukova, L.V. : 4 2 Fodor J. • 195 Dong, C.F. ( £•&£) : 105 fOdor-Csanyl, P. : 266 Dong, L Y. (3E3*> : 151 fogelberg, B. : 52 Dong, T R. ( SxsH : 32 Folcher, G. : 92 Dong, Y C. ( SJ!#) : 233 Friedlander, E.M. : 25 Dorroond, A : 92 Friehtnelt, V : 76 Doss, K. G..R . : 1 Fu, L. (# £ > : 82 Dougan, A..D . : 65 Fu, M. (# fc ) : 32, 47 Dougan, R .J. : 65 Fujiwara, : 30, 33. 51 Dowswell, S.A. : 110 Fukai, R. 253 Droste, R . : 252 Fukumura, T. 210 Du, U.S. (&&# ) : 198 Fukuzawa, T. 30 Du, H Y. ( *U*i ) : 181 Furukawa, M. 175 Du, L (tfc 4&) : 239 Fusban, H. U. 58 Gaggeler, Duan , H. M. (asm : 102 H. 261 Duan Y, 91 Gallagher, S.A. : 77 V F. ( a-s-S ) : Gallet, M. Dvorak. Z. : 70 : 150 Gan, Y.X. 211 Eckhard H. : 286 Egan, A Ganz, M. 159 : 246 Gao, L.C. 151 Ehmann, W.D. : 147 ( &M" ) Ekstrom, Gasparini, G.M. : 89 B. : 52 Ganssauge, Ellis, W R. : 110 E. : 25 Gauglitz, R. : 76 Elmaleh. D.R. : 244

295 - Ge, Q.R. (MtKC ) : 112 Henderson , R. : 36 Hong, J.F . ( m*\t$ ) : 288 Gelbke, C.K. 26 Henrion, P.N. : 291 Genet, M. : 116 Herrmann, G. : 3, 152 Glascock, M.D. : 53, 158 Herrmann, J. : 25 GSkturk, H. : 52 Hiltunen, J. : 245 Goldacker. H. : 62 Hirsch, A .S. t 38 Gotag , J. L. ( £1£*$ ) : 239 Hoffman, D.C. : 25. 3 Gordon, G.E. : 144 Hoffmann, P. : 204 Gorgenyi, T. : 114 Hogan, J.J . : 31 Goswami, A. : 24 Holm, E. : 137 . 253 Grabner. H. : 265 Horiuchi, K. : 176 Green, R. : 37 Horwitz, E.P. : 61 Gregorich, K. : 36 Hoste, J. : 11, 148, 184 Grierson, J.R. : 209 Hou, H.Q. : 252 Grudpan, K. : 134 Hou, S.H. (£&# ) : 107 Gu, D.X. (Wfjftft) 179 Hu, H.Z. ( #ff4? ) : 88 Gu, M.J. (£$?& ) 192 Hu. J.X. ( fl&flF ) : 91 Gu, M.Y. (J9#i£ ) 234 Hu, X.F. ( #£X) : 248 Guo, A.L. (U$[& ) : 67, 99 Hu, Y.L. ( #3LJ# ) : 238 Guo, G. ( # BO : 132 Hua, Z.F. ( #£# ) : 197 Guo, S.L. : 284 Huang, H.A. ( £tt$ ) : 109 Guo, X.Z. : 225 Huang, H.X. (jHtlff) : 107 Guo, Z.H. ( £>£$ ) : 84 Huang, J. ( % •& ) : 237 Guo, Z.Q. ( *PJMU : 250 Huang, M.X. ( %£$[ ) : 94 Guillaumont, R. : 116 Huang, S.N. ( £&#• ) : 22 Gustafsson, H.A. 1 Huang, Y. ( ft ?fc ) : 250 Gutay, L.J. : 38 Huang, Y.F. ( ##Sf ) : 102 Gutbrod, H.H. ; 1 Huang, Y.P. ( $%%• ) : 273 Gutmacher, R.G. : 153 Hulet, E.K. : 65 Haase, G. : 25 Huo, Z.C. ( ££S ) : 233 Haeberlin, S.T. : 164 Hurso, H. : 267 Hall, H. : 36 Hussonnois, M. : 116 Hakkila, E.A. : 153 Ikeda, N. : 45 Hamajima, Y. : 33, 51, 30 Ikonnikov, M.J. : 285 Han, H.Y. (##MR ) : 22 Ikuta, S. : 169, 262 Hanke, H.D. : 155 Hus, E. : Hartmann, G. 272 259 Imamura, M : 33, 51. 175 Hasanen, E. Inoue, M. Hashimoto, T 194 : 139 Hashizume, A : 30, 271 Irie, H. : 177 Hatsukawa, Y : 169 Ishii, T. : 176 Hayashi, Y. : 40 Ishikawa Y. : 177 He, A.D. (ftttifr27 )1 : 76, 83 Ito, A. 128 He, J.Y. ( ft&i ) : 108 Ito, Y. 169 Hedvall, R. : 137, 166 Iwamoto, M. : 146 Heilgeist, M. : 90 Iwata, S. : 165,177 Heinzinger, K. : 278 Iyer, R.S. : 292 Helmer, R.L. ": 37 Jackson, K.P. : 37 Jamil. K. : 284

- 296 - Jedinakova V. : 70 Kolb. B. : 1 Ji, G.K. ( mm® ) z 202 Komura, K. : 140 Ji. L.Z. ( mm ) : 228 Kopecky. J. 29 Jia, Z. ( 1 *n 198 Korpela, H. 221 Jiang , D L. ( #&S ) 108 Korteling, R : 37 Jiang F S. I ??SS ) 69 Koulkes-Pujo A.M. : 92 Jiciiq , G Q-. I «iU-2 ) 10 0 Kowdlciyk, J. : 270 J i a ng . L G.. {iLm.) 66 Koyama, M. : 182 Jiang, M S.. ($£&) 238 Kozma, P. 25 Jiang, Y. I ill & •) : 202 Kriegel, S : 76 Jiao , R.Z- (:t£S! ) 78 Kroh, J. : 281 Jiao, X.Q. < &*% } 44 Krupa, J.C : 116 Jin, G.M. ( If #JTJ ) 32 Kubo, M.K. : 2 35 Jin, J.N. { &i® ) 115. 168 Kubota, Y. : 3030,, 3333. 51 Jin , S.S. ( ±m- ) 115 Kulakov, B A. : 25 Jin , Y.T. ( &.S& ) 215. 224 Kung. H.F. : 215215.. 222 4 Jing Y.Z. ($8? ) 129 Kiang , H. 241 Jore D- : 279 Lahalle, M.P-. : 116 Judek, B : 25 Landrum, J.H. : 65 Kabalka, G.W. 218 Langrock, E.J. : 25 Kadotani H • I 86 Lebedev, I.A. : 13 Kaffrell , N. : 35 Le Duigou, Y. : 160 Kairento , A.L. : 221 Le Marechal, J.F. : 92 Kakihana , H. :: 86, 57 Lee. D. : 25, 36 Kang, M.X. {&*{&) 199 Lefevre, G. : 116 Kang, S.F. ( #'££ ) 112 Lei, K.J. (HOSP!) 211 Kang, T.S. ( ??Ak* ) 170 Leopold, D. : 267, 268 Kang, X.H. (#5«) 111 Levins, D.M. : 110 KarlP J. : 154 Li B. A. 219 Kasarskis, E.J. : 147 Li C.S. #££ ) 202 Kasza, J. 266 Li G.Q. £fr# ) 199, Katada, M. : 43, 254 Li M.L. £/S & ) 213 Kato. Y. : 177 Li P.Q. $%-& > 274 Kaufman , S. : 3 7 Li T.K. 15 4 Keheyan , Y. : 49 Li W.X. ^%*T ) 32 47 Keiling, Ch D. 58 Li X.F. £3i* ) 67 98 Keinonen, J : 221 132 Khalil, S. 270 Ll X.F. 129 Khan, H.A. 284 Li X.T. 82 Khare, S.S. 147 Li X.X. $&fi ) 162 Khodai-Joopary, A. : 284 Li Y.J. $&# ) 230 Kimura, K 276 Li Y M. #SH* ) 180 Kizuka, H. : 244 Li Y N. £%9 > 167 Klenk, H. : 259 Li Z L. &$.# ) 181 Kluge, H.J . : 152 Li Z M. **ft ) 232 Koch, G. : 8 Li Z Y. *££) 108 Koch, L. : 56 Lian , L.J . (mm) : 248 Kohno , I. : 40 Liang, G. L . ( »tt ) : 219 Kojima, M. : 210 Liang, J.F. ( &fe*I ) : 102

- 297 - Liao. S. ( % t> ' - 22S Lycke. W. : 150 Liao. S.S. ( £-£-!? ) : 78 Lynch. W.G. : 26 Lieser, K.H. : 68 Ma. J.Y. ( 2}%3. ) : 41, 261 Lin. C.C. 263 Ma. S.L. I 3&*. ) : 16 3, 173 Lin, C.S. #&*) 94 Maeda, M. ; 210 Lin. J.F. 219.248 Maddock. A.G. : 5 Liu, Q.F. 248 Meu-jaca. !1. ; 4 0 Lin, S.M. ##L ) 28 7 Mahadeviah, I. : 172 Lin, Z.H. #*& ) 123 Mahi, M. : 38 Lin, Z.J. #2M&) 69 Malik. S.R. : 227 Lindner, L : 29 Mandic. D. : 185 Ling. D.K. : 117 Manni. G.B. : 212 Liu, B.B. n&$ ) 181 Manninen, P. : 194 Liu, B.R. »t) 74 Manohar, S.B. : 24 Liu, B.L. *H63. ) 16. Mao, J.J. (•££*£ ) : 58. 81, 215, 224 225 82 Liu, G.D. 248 Mac. X.Y. {*££%.) : 153. 173 Liu, G.X. m&> 121 Mao, Y.X. : 147 Liu, H.S. *i#.4> 193 Mao, Y. ( 3F -=• 3 : 84 Liu, J. ( / ft) : 101 Markesbery, W.R. * 147 Liu. L. ( j 77) : 67,99 Martin, W.R.W. : 209 Liu, L.M. fl## ) : 109 Marx. G. : 58. 76, 252 Liu, L.Z. *l*£ ): 107 Masson, M. : 264 Liu, Q.L. W?i% ) ; 104 Masuda, T. : 140 Liu, S.Y. *1£~ ) : 91 Matsubara, T. : 182 Liu, T. (5 ®) ; 248 Matsuoka, N. : 188 Liu,X.J. : 225 McGaughey, P. : 25 Liu, Y.F. flj&iT) : 66, 250 Meng, J.C. ( JStlJS ) : 22 Liu. Y.G. •ttSRJ ) : 142, 199 Meng. M. ( £ ^C ) : 215 Liu, Z.H. : 2 74 Meng , Z.G. ( £&# ) : 10 2 Liu, Z.W. (*!**) ; 280 Mignonsin, E.P. : 138 LShner, H. : 1 Minai, Y. : 235 Loos-Neskovic, C. : 127 Miao, L. ( & $• ) : 4 4 Lougheed, R.W. : 65 Miassoedova, T.G. : 285 Loveland, W; : 34 Miura. T. : 169. 262 Lowson, R.T. : 257 Miyachi, T. : 51 Lu, J. ( fe*H£ ) : 226 Moccia, A. : 6 3 Lu. K. ffi & > 173 Moens, L. : 184 Lu, S. J. : 84 Molinet, R. : 56 Lu, S. s. izma : 211 Molzahn, D. : 159 Lu, X. F. ( &$$ ; 243 Momoshima. N. : 139. 187, Lu, z. D, ( &&& ) : 121 188 Ludewigt B. : 1 Mooney, E. : 172 Lund, E. : 52 Mori, T. : 177 Luo H. 157 Morrissey, D.J. : 27 LUO, S. ipm ) 273 Motoyama, I. : 254, 277 Luo , S. 129 Mou, W.T. ( 47?& ) : 41, .261 Luo, s. ( $&%) 202 Muller, A. : 212 Lux , F. 164 Murakami, Y. : 176

- 298 - Hurcmura, T. : 95, 128 Poskanzer, A.M. Mutou, M. : 51 Powell, J.E. : 117 Mya-soedov, E.F- : 13 Prakash S. : 24, 48 Nagasato, Y. : 187 Projahn D. : 259 Nagy, L.Gy. : 205 Pu, S-G t ^m) : i Naik, H. : 24. 48 Pujari, P.K. : 48 Nair, A-G.G. : 24 Put, M. : 291 Nakahara, H. : 40. 169. 175. Qian H.S. Hi*>& ) •125 126 196, 262 Qian Q.F. ( R%& ) 200 201 Nakashima, S. : 254 Qian X.Z. (4t£*£) 162 Nash, K.L. : 59 69 Navratil, J.D. : 7 Qin, .Q.Z"' . (*£&' 80, 81 Qin, R.W. (*Af*3 129 Nikolic, V. : 207 Qin, Z.X. (**£ 88 Nishikawa, S. : 165 Qiu, L. < J? & ) : 118 Nishimura, S. : 210 Qu, Z.M. ( &&& ) : 129 Nitsche, H. : 71 Qui, Y.E. (4M8.&) : 197 Nourmand, M. : 75 Ramaniah, M.V. : 24 Nozaki, T. : 12, 146, 235 Ramsey, H.D. : 73,, 120 Nurmia, M.J. : 36 Re, H.N. ( fEft?) :: 233 Oi. T. : 57, 86 Reddy, A.V.R. : 24 Okai, T. : 188 Rees, T.F. 59 Oki, Y. : 45 Reeve, K.D : 110 Oldfich, N. : 286 Renner, T. 1 Ollila, K. : 119 Revel, G. 145 Oschinski, J. : 265, 289 Riedesel, : 1 Ossicini, L. : 212 Rimke, H. 152 Otsuki, T- : 40 Ritter, H : 1 Otten, E.W. : 152 Rogowski, : 35 Ouyang. Z.Y. (&P8@3£) : 173 Rong, T.W. (££*> 243 Roos, P. : 184 Pages, M. : 9 Rosel, B. 268 Paderewski, G.L. : 38 Rossler, K : 21 Pan, Q. Y. (ar&X ) : 44 Roth, E. : 264 Pan, X.X. (ftrOT) : 60 Rotta, M.C. : 189 Parker, D.J. : 31 Rowland, F. S*. : 4 , 292 Pate, B.D. : 209 Rudstam, G. : 2, 52 Patterson, L.K. : 279 : 173 Ruster, W. 152 Peng, H.C. : (-fc8.fi> Ruth, T.J. 209 Penttila-Hiltunen, P. : 245 Ryan, R.K. 110 Persson, B. : 253 Rydberg, J- 135 Pettersson.H. : 137, 166 Sahakundu, S.M. : 24 Peuser, P. : 152 Saito/Y. :: 276 Pille, F. : 25 Sakamoto K. : 30 33, 51 Pinter, T. : 205 183 Plewinsky, B. ? 267, 268 Sakanoue M. : 14 0 Pochodzalla, J. : 26 Samhoun, K. 65 Polak, P. : 29 Sandquist, G.M. : 203 Porile, N.T. : 25, 38 Sangster, T.C. : 38

- 299 - Sano, H. : 43 46, 254, 277 Stoessl, J. : 209 Sato, D. : 30 Stolk, Th.M-W. : 2 42 Sato, T. : 43 Stollenvjerk, IV. H. : 90 SatteLberger, P. : 152 Stringfellow, B.C. : 38 Scharenberg, R.P. : 38 Su, S.X. (^^} : 44 Scheele, R.D. : 77 Sueki, K. : 40 Schmidt, L. : 159 Sugiyama, H. ,: 177 Schmieder, H. : 62 Sullivan, J.C. : 1 04 Schonemann, W. : 25 2 Sun , J.F. < ### ) 211 Schonenberger, H. : 164 Sun, J.X. 161 17 Schul?, . W. • ?5. 6\ 77 •o-,\n , v. - y seaborg, G.T. : 25, '34, 36 Sun , P.N. ( 3H$*) : 67, 98, Seatonberry, B.W. : 110 99 . 130 Sha. L.M. {#$£ ) : 156 Sun, S.L. ( 3H£| ) : 102 Shakshooki. S.K. : 270 Sun, S.Y. (#*7G} : 219 Shamaev, V.I. : 141 Sun, T.Y. ( ##£) : 4 7 Shen, D.C. ( #.$# ) 228 Sun, X.H. ( #&#) : 4 7 Sheng, H.Y. ( $*F& ) 260 Sun, X.J. ( -JMS? ) : 32 Shi, Q.X. : 223 Sun , X.R. ( ##&) : 41, 261 Shi, R.F. : 225 Sun, Z-H- Shi, W.Y. ( #,±35 ) : ( #ta) : 38 273 Suzuki M. : 255 Shibata, S. : 30, 3 3. 51 Suzuki T. Shiraishi, N. : 188 : 169 Shiue, C.-Y. : 222 Tachimori, S. : 72 Shoji, H. : 45 Tada, T. : 140 Short, S.A. : 257 Tai, D.R. ( *P(|.#. ) : 101 Shukla, S.K. : 212 Takashima Y. : 139 Takada, J. : 182, 187, 188 Sial, A. 284 Takeda, M. : 262 Silva, R .. J.' : 19 Takeishi, H. : 95 Simonits , A. 148 Tamai, T. : 165, 177 Sinclair , G. 290 Tanaka Y. : 165 Sjoblom, K.L. : 272 Tang , B L. ( iftffltt ) 130 Skalberg , M. 35, 185 Tang, F X. (vm%) 60 Skarnemark, G : 35 . 185 Tang , J J. (&&®) 84 Solymosi, J. 205 Tang , T Y. (M*O 192 Song, C.L ( fc*± ): 102 Tang, Z G. : 225 Song , D.H : 213 Tang, Z H. 84 Soto, M. (fcm) Tao, Z.Y. ( $») : 106,. 12 Soylu, A. 33, 51 Taylor, C. G. : 134 Soylu, K. 208 Teng, R. : 222 Spanier, L 208 Tetzel, H. -H. : 26 Speranza, M : 52 Tetzlaff, H. : 35 Spruss, Th . : 49 Thompson, CM. : 1 47 Srivastava 164 24 Tian , B.S. ( H#£ ) 108 Stade, K.Ch. B.K: .25 :8 Tian , S.H. ( Will) 234 Stamm, H.H. : 155, 258 Tian , W.Z. ( toft*. ) 53 Stecher-Rasmussen, F. 29 Tjioe, P.S 242 Stieglitz, L. : 96 Tomar, B.S 24 Stoecklin, G. : 15 Tominaga, T : 235

•- 300 - Tong. C.H. ( Hffe«S ) : 167 Wang, W.J. ( 3LX£ ) ' 79 Tong. J.H. ( -£3111 ) : 101 Wang. W.Q. ( £jS[ ) : 100 Tong. W.G. I 1&X?b ) : 106 Wang, X.B. ( 3if"&) : 225 Topham, S-A. : 110 Wang, X-F. (i^~t ) : 121 Tout, R.E. : 14 3 Wang. X-H. ( S^ ) '- 121 Trautmann, W. : 35, 15.2 Wang, X.Y. ( i#TT ) : 250 Tsang, M.B s 26 Wang. Y.L. ( 5-zrA ) : 113 Tsou, H-R- : 293 Wdnq, Y.Q. ( 12-1 > : 161. 174 Tsulcada, M j 196 Wang , Y.X. ( •^•fic ) '- 136 Tu. a. (g M ) : 180 Viang. Z.L. ( JE.'S** ) • 50. £8 7 Tu, S.D. ( MM& ) 161 , 174 Wang, Z.Q- ( rEfi^ ) : 250 Tilrler, A- : 36 Warwick, A. : 1 Uehara, A. -. 255 Watababe.M. : 2 77 Ueno. K. : 128 Watanabe, Y. : 46 Vajda, N. : 205 Wegen, D. : 252 Van den Hamer, C.J.A. 242 Wehner, E. : 114 Van Hende. J. : 184 Wei, L.S. C *&E£) : 69 Vance, D.E. : 14 7 Weishaupt, M. : 90 Vanlic- Razumenic, N. 207 Wen, N.-K. : 43 Vater, P. : 284 White, J.P. : 172 Verbruggen, A. : 150 Wiebe, L.I. : 247 Verdingh, V. : 160 Wieman, H. : 1 Veselinovic, D. : 207 Wild, J.F. : 65 Viirsoo. M. : 189 Wilkins, B- : 37 Viola, V.E. : 23 Williams. J.D. : 73 , 120 Vodicska, M. : 205 Wilson, J.S. : 24 7 Volkers, K.J. : 242 Wolf, A.P. : 17 von Gunten, H.R. : 36 Wu, C.C. ( £tt-# ) : 66 Vora, M. : 217 Wu, M. ( £ '&) : 85 Waelkens. M- : 184 Wu, W.S. iHl! ) : 118 Wahl, A.C. : 3 9 Wu, X. ( & ft) : H3 Wakabayashi, H. : 86 Wu, Y.H. (£*& ) : 250 Walker. T.P- : 23 Wu, Z.M. : 214 Walters, W.B. : 28 Wu. Z.X. (£#*T) = 237 Wang , B.Y. : 79 Wukovnig, S. : 217 Wang , C.P. C£#&) : 243 Xia. J-X. ( Xfti-f ) . 125 Wang , D.X . ( 2.&B ) : 6 Xia, K.L. ( &3r^ ) : 193 Wang , L.A. ( 5.5L* ) : 129 Xia. X.Q. 1 £&M ) : 211 Wang , L. ( 3E£ ) : 3.7 9 Xia, Y.X. ( X&S ) : 124 Wang , L.J. ( £4-4' ) : 132 Xia, Z.M. : 225 Wang , L.M. ( £# ) ) : 213 Xie, Z.C. ( $&£: ) : 142 Wang , w.c. ( &.XR. ) : 102 Xin, W.D. ( *Xfe ) : 105

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