IAEA Laboratory Activities

TECHNICAL REPORTS SERIES No. 90

THE IAEA LABORATORIES AT VIENNA AND SEIBERSDORF THE INTERNATIONAL LABORATORY OF MARINE RADIOACTIVITY AT MONACO THE INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS. TRIESTE THE MIDDLE EASTERN REGIONAL RADIOISOTOPE CENTRE FOR THE ARAB COUNTRIES, CAIRO

FIFTH REPORT i

j INTERNATIONAL ATOMIC ENERGY AGENCY,VIENNA, 1968

IAEA LABORATORY ACTIVITIES

Fifth Report The following States are Members of the International Atomic Energy Agency:

AFGHANISTAN GERMANY, FEDERAL NORWAY ALBANIA REPUBLIC OF PAKISTAN ALGERIA GHANA PANAMA ARGENTINA GREECE PARAGUAY AUSTRALIA GUATEMALA PERU AUSTRIA HAITI PHILIPPINES BELGIUM HOLY SEE POLAND BOLIVIA HUNGARY PORTUGAL BRAZIL ICELAND ROMANIA BULGARIA INDIA SAUDI ARABIA BURMA INDONESIA SENEGAL BYELORUSSIAN SOVIET IRAN SIERRA LEONE SOCIALIST REPUBLIC IRAQ SINGAPORE CAMBODIA ISRAEL SOUTH AFRICA CAMEROON ITALY SPAIN CANADA IVORY COAST SUDAN CEYLON JAMAICA SWEDEN CHILE JAPAN SWITZERLAND CHINA JORDAN SYRIAN ARAB REPUBLIC COLOMBIA KENYA THAILAND CONGO, DEMOCRATIC KOREA, REPUBLIC OF TUNISIA REPUBLIC OF KUWAIT TURKEY COSTA RICA LEBANON UGANDA CUBA LIBERIA UKRAINIAN SOVIET SOCIALIST CYPRUS LIBYA REPUBLIC CZECHOSLOVAK SOCIALIST LUXEMBOURG UNION OF SOVIET SOCIALIST REPUBLIC MADAGASCAR REPUBLICS DENMARK MALI UNITED ARAB REPUBLIC DOMINICAN REPUBLIC MEXICO UNITED KINGDOM OF GREAT ECUADOR MONACO BRITAIN AND NORTHERN EL SALVADOR MOROCCO IRELAND ETHIOPIA NETHERLANDS UNITED STATES OF AMERICA FINLAND NEW ZEALAND URUGUAY FRANCE NICARAGUA VENEZUELA GABON NIGERIA VIET-NAM YUGOSLAVIA

The Agency's Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Headquarters of the Agency are situated in Vienna. Its principal objective is "to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world".

Permission to reproduce or translate the information contained in this publication may be obtained by writing to the International Atomic Energy Agency, Karntner Ring 11, A-1010 Vienna I, Austria.

Printed by the IAEA in Austria

September 1968 TECHNICAL REPORTS SERIES No. 90

IAEA LABORATORY ACTIVITIES

The IAEA Laboratories at Vienna and Seibersdorf

The International Laboratory of Marine Radioactivity at Monaco

The International Centre for Theoretical Physics, Trieste

The Middle Eastern Regional Radioisotope Centre for the Arab Countries, Cairo

Fifth Report

INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA, 1968 IAEA LABORATORY ACTIVITIES - Fifth Report (Technical Reports Series No.90)

ABSTRACT. This fifth report describes development and work during the year 1967. It includes activities of the IAEA Laboratories at Vienna and Seibersdorf, the International Laboratory of Marine Radioactivity at Monaco, the International Centre for Theoretical Physics at Trieste, and the Middle Eastern Regional Radioisotope Centre for the Arab Countries at Cairo. Contents: ThelAEA Laboratories at Vienna and Seibersdorf: Introduction; Standardization of measurement and of analytical methods related to peaceful applications of nuclear energy; Services to Member States and International Organizations; Chemical and physico-chemical investigations relevant to the Agency's programme; Nuclear techniques in hydrology; Nuclear techniques in medicine; Nuclear techniques in agriculture; Nuclear electronics service and development; Administrative matters. — The Inter- national Laboratory of Marine Radioactivity at Monaco: Introduction; Research; Administrative matters. — The International Centre for Theoretical Physics, Trieste: Assistance to developing countries; Research activities; Administrative matters; Annexes. — The Middle Eastern Regional Radioisotope Centre for the Arab Countries, Cairo: Introduction; The scientific programme of the Centre; Publications on work done at the Centre; Finance; Annex. Entirely in English.

(155 pp., 16x24 cm, paper-bound, 31 figures; 1968) Price: US$1.00; 8/4 stg

IAEA LABORATORY ACTIVITIES, FIFTH REPORT IAEA, VIENNA, 1968 STI/DOC/10/90 FOREWORD

This fifth "IAEA Laboratory Activities" report describes the work during the year 1967. It includes activities of the Agency's Laboratories at Vienna and Seibersdorf, the International Laboratory of Marine Radioactivity at Monaco, the International Centre for Theoretical Physics at Trieste, and the Middle Eastern Regional Radioisotope Centre for the Arab Countries at Cairo.

The Agency expresses its gratitude to the Governments of Austria, Monaco, Italy and the United Arab Republic for their generous continued assistance.

CONTENTS

THE IAEA LABORATORIES AT VIENNA AND SEIBERSDORF

I. INTRODUCTION 3

II. STANDARDIZATION OF MEASUREMENT AND OF ANALYTICAL METHODS RELATED TO PEACEFUL APPLICATIONS OF NUCLEAR ENERGY 4 1. Calibration of radionuclides 4 1.1. Development of calibration apparatus 1.2. Distribution of calibrated radioactive samples 1.3. Participation in an intercomparison for 60Co 2. Techniques associated with standardization 6 2.1. Fabrication of lithium-drifted germanium detectors 2.2. Source preparation by electro-spraying 3. Neutron fluence measurements 7 4. Radiation dosimetry 8 4.1. Calorimetric measurements 4.2. Ferrous sulphate dosimeters 4.3. LiF thermoluminescent dosimeters 5. Analytical chemistry (Reference materials) 11 5. 1. Analysed low-grade uranium ores 5.2. Analysed sample of uranium oxide containing trace impurities

III. SERVICES TO MEMBER STATES AND TO INTERNATIONAL ORGANIZATIONS 13 1. Austria (Promethium-147 in urine) 13 2. Peru (Determination of radionuclides in milk and air filters) .... 13 3. Somalia (Analysis of mineral samples) 14 4. Sudan (Determination of beta activity) 14 5. Tunisia (Determination of uranium in ores) 14 6. UN Food and Agricultural Organization (Applied neutron activation analysis: determination of mercury in pesticide residues) 14

IV. CHEMICAL AND PHYSICO-CHEMICAL INVESTIGATIONS RELEVANT TO THE AGENCY' S PROGRAMME 18

1. Low-level radioactivity (LOWRA) quality control programme .... 18 1.1. Methods of analytical quality control 1.2. The present situation in analytical quality control 1.3. Analytical quality control in applied radiochemical analysis 2. Studies on decomposition under radiation 23 2.1. Decomposition of folic acid 2.2. 7-sterilization of packaged biomedical products 2.3. Effect of y-irradiation on human blood-plasma proteins

3. Purity of commercial radiochemical preparations 26 3.1. Studies on thyroxine 3.2. Studies on 203203]Hg-containin g compounds 4. Safeguards programme 27 4.1. Analytical standard samples 4.2. Neutron activation analysis 4.3. Precise tritium assay 4.4. Plutonium in urine

V. NUCLEAR TECHNIQUES IN HYDROLOGY 29

1. Tritium 29 1.1. Enrichment by electrolysis 1.2. Isotope fractionation from distillation 1.3. Gas counting 1.4. Preparation of n-butane for tritium gas counting 1.5. Liquid scintillation counting 31 2. Carbon-14 3. Scandium-46 labelled compounds as tracer for water 31 4. Oxygen isotopic composition 32 VI. NUCLEAR TECHNIQUES IN MEDICINE 33 1. Development of methods and instruments 33 1.1. Medical activation analysis 1.2. Radioisotope scanning 1.3. Whole-body counting 1.4. Profile scanning 1.5. Thoron assay system 1.6. Computer programme for curve-fitting 2. Support of other Agency activities 45 2.1. Radionuclide monitoring 2.2. Labelled proteins for the study of protein metabolism in malnutrition 2.3. Applications of whole-body counting 2.4. Study of toxicity of Thorotrast in Vienna cases

VII. NUCLEAR TECHNIQUES IN AGRICULTURE 47 1. Soil fertility, irrigation and crop nutrition 47 1.1. Co-ordinated rice project 1.2. Co-ordinated maize project 1.3. Co-ordinated wheat project 1.4. Co-ordinated research programme on tree crop fertilization 1.5. Crop nutrition and water use efficiency 1.6. Co-ordinated programme on nutrient supply and movement in soil systems 1.7. The analysis of nitrogen-15 in biological materials 2. Entomology 64 2.1. Mediterranean fruit fly 2.2. Olive fly 2.3. Tsetse fly 3. Plant breeding 72 3.1. Barley projects 3.2. Wheat projects 3.3. Rice projects 3.4. Neutron seed irradiation programme 3.5. Radiation services

VIII. NUCLEAR ELECTRONICS SERVICE AND DEVELOPMENT 76

1. General 76 2. Programmable computer interface 76

IX. ADMINISTRATIVE MATTERS 82

1. Training 82 2. Laboratory equipment donated by Governments of Member States . . 82 3. Finance 83 4. Professional staff of the laboratory 86 5. Publications by staff members 91 6. Papers presented at scientific meetings by staff members 94

THE INTERNATIONAL LABORATORY OF MARINE RADIOACTIVITY AT MONACO

I. INTRODUCTION 99 1. The Programme 99 2. International co-operation 99 3. Scientific meetings attended 99 4. Visitors 100 5. Co-ordinated research programme 100

II. RESEARCH ..101

1. Work at sea 101 1.1. Diffusion processes in the sea 1.2. Penetration of isotopes into the sea bottom 1.3. Zooplankton observations 1.4. Organic aggregates 2. Work in the laboratory 103 2.1. Chemistry of sea water 2.2. Chemistry of sediments 2.3. Radiobiology of marine organisms

III. ADMINISTRATIVE MATTERS 113

1. Site, facilities and equipment 113 2. Finance 113

3. Professional staff of the laboratory f . 113 4. Publications by staff members 114

THE INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS, TRIESTE

I. ASSISTANCE TO DEVELOPING COUNTRIES 117 1. Associate memberships 117 2. Fellowships and other positions 117 3. The Advanced School of (Theoretical) Physics 117 4. Long-term seminars and courses 117 5. Federated institutes 118 6. Dissemination of scientific information 118

II. RESEARCH ACTIVITIES 121 1. Nuclear physics 121 2. Field theory . .... 121 3. Infinite-component field theories 122 4. Bound states and quark model 122 5. N/D method ...122 6. Scattering Regge poles I23 7. Group theory 123 8. Symmetries 124 9. Dynamical problems I24 10. Superconvergence and current algebra 125 11. References 125 III. THE CENTRE AS AN INTERNATIONAL FORUM FOR PERSONAL CONTACTS BETWEEN THEORETICAL PHYSICISTS FROM COUNTRIES AT ALL STAGES OF DEVELOPMENT 133 1. Member states and intergovernmental organizations represented 133 2. Number of scientists who were at the Centre 133

IV. ADMINISTRATIVE MATTERS 134 1. Finance 134 2. Statistical digest 135 2.1. Scientific staff 2.2. Participation of scientists expressed in man/month 2.3. Participation in extended seminar courses 2.4. The Advanced School of Physics 2.5. Library 2.6. Scientific Information

ANNEX A: PROFESSIONAL STAFF OF THE CENTRE, VISITING SCIENTISTS AND ASSOCIATES, GUEST LECTURERS, CONSULTANTS, FELLOWS, AND VISITORS FROM FEDERATED INSTITUTES 138

ANNEX B: THE INTERNATIONAL COURSE ON NUCLEAR PHYSICS: LECTURERS AND SEMINAR LECTURERS 141

THE MIDDLE EASTERN REGIONAL RADIOISOTOPE CENTRE FOR THE ARAB COUNTRIES , CAIRO

I. INTRODUCTION ...145 I. Special visits 145

II. THE SCIENTIFIC PROGRAMME OF THE CENTRE 146 1. Training 146 2. Research 146 2.1. Hydrology 2.2. Agriculture 2.3. Entomology 2.4. Medicine 2.5. Laboratory, research and training facilities

III. PUBLICATIONS ON WORK DONE AT THE CENTRE 153

IV. FINANCE 154

ANNEX A. RESEARCH TEAMS AT THE CENTRE 155

THE IAEA LABORATORIES AT VIENNA AND SEIBERSDORF

I. INTRODUCTION

The activities at the Seibersdorf Laboratory and the laboratory activities at Headquarters were continued in general at the same level as before, and the arrangement of this report is similar to that of 1966. During the course of 1967, however, the Division of Safeguards and Ins- pection undertook the inspection of a nuclear fuel re-processing plant. The Laboratory provided assistance in this campaign by preparing standard samples and performing analyses on samples of plant process solutions. As many of these solutions have a high plutonium content, it was necessary to convert one laboratory to enable the handling of plutonium samples to be carried out in a safe manner. It should be mentioned that the activities in these Laboratories are either of a service nature to Member States or are very closely inter- woven with the appropriate aspects of the Agency's programme. Training at the Agency's Laboratories remains an important part of its service activities and one course on Bioassay Methods was held with 13 participants from Member States. In addition, 10 Fellows participated in "in- service" training for longer periods.

3 II. STANDARDIZATION OF MEASUREMENT AND OF ANALYTICAL METHODS RELATED TO PEACEFUL APPLICATIONS OF NUCLEAR ENERGY

In accordance with one of the main statutory tasks of the International Atomic Energy Agency, standardization work has continued in 1967 in the fields of radionuclide calibration, radiation dosimetry, chemical and physico-chemical analysis of materials of nuclear interest. The achievements during the period under review are reported below.

1. CALIBRATION OF RADIONUCLIDES

1.1. Development of calibration apparatus

In close co-operation with the Centre d1 etudes nucleaires, Saclay (France), a semi-automatic installation for the calibration of solid radioactive sources by the 4;r (proportional counter) - 7 coincidence method has been developed. The 47r-counting channel (counter, amplifier, discrimina- tor, dead-time unit) and the sample changer (Fig. 1), which has several unique features, were constructed by the Electronics Section and by the

FIG. 1. Details of the sample changer (the 4ir - proportional counter within the lead shielding is not visible).

4 VIENNA AND SEIBERSDORF 5

Mechanical Workshop of the IAEA laboratory. No commercially available devices could be used or adapted because they could not meet the conditions required. The model can handle a stack of up to 50 sources in one run (see also section VIII, Nuclear Electronics Service and Development). The 7-detector (3 X 3 in Nal) and the main electronics counting system were a donation by the Government of France, as were a small DASSAULT 8-48 computer. The latter normally works on-line and after each source prints-out the results corrected for background, for finite dead-times and concidence resolution time. Corrections for radioactive decay and other operations can also be made automatically.

FIG. 2. Semi-automatic equipment for solid radioactive source calibration using a 4ir (p. c.) - y coincidence method.

The whole assembly (Fig. 2) has already been tested extensively and will considerably facilitate 47r-y coincidence calibrations.

1. 2. Distribution of calibrated radioactive samples

This service to Member States was continued. In comparison with previous years the number of items distributed was somewhat reduced in 1967 because considerable time had been devoted to the improvement of calibration techniques and devices. The main item of the calibration programme was the work on the set of eight Y-sources covering the 7-energy range between 60 and 1840 keV. Details are given in Table I. 6 II. MEASUREMENT AND ANALYTICAL METHODS

TABLE I. RADIOACTIVE STANDARDS DISTRIBUTED DURING 1967

Total Type of Number of Number of Number of Radionuclide activity samples samples recipient Member (fiCi) distributed institutes States

Caesium-137 100 solution 59 47 26

Americium -241 100 solution 52 32 19

Cob alt-60 100 solution 40 31 19

Americium-241 10

Cobalt-57 10

' Mercury-203 20 Set of 8 1112

Sodium-22 10 calibrated (i.e. 139

Caesium-137 10 solid complete

Manganese-54 10 sources sets)

Cobalt-60 10-

Yttrium-88 10

TOTALS 1263 118 35

1.3. Participation in an intercomparison for 60Co

The laboratory participated in an intercomparison organized by the International Bureau of Weights and Measures, Paris. Two 60 Co solutions of about 25 /uCi/g and about 2. 5 /uCi/g were to be calibrated. A large number of sources had to be measured repeatedly in order to obtain a good statistical precision. The Laboratory's values agreed to better than ± 0. 1% with the "best" values.

The greatest part of the systematic error was due to errors in determining the masses of the sources (up to ± 10 ng).

2. TECHNIQUES ASSOCIATED WITH STANDARDIZATION

2.1. Fabrication of lithium-drifted germanium detectors

Since several sections of the laboratory are interested in using these detectors, which are still very expensive, methods of fabricating these from relatively cheap germanium ingots were developed. A special device for mounting the detectors on the liquid nitrogen container was also constructed. VIENNA AND SEIBERSDORF 7

At present, several detectors with volumes up to 12 cm3 are being prepared. For a 3.5 cm3 detector, a half-width of 2.8 keV for the 1.33 MeV 7-line of 60Co was measured, of which much is probably from the associated electronics. Another detector of 4 cm3 was prepared for the Chemistry Section. Big germanium detectors will be used for checking the radionuclidic purity of standard solutions. This problem is expected to become even more important in the years to come since, in many cases, unwanted activities limit the use of radioactive standards.

2.2. Source preparation by electro-spraying

The calibration of radionuclides with complicated decay schemes becomes easier if the self-absorption of charged particles within the solid sources is reduced. Electroplating is a convenient technique, but it cannot be applied to alkali and alkali earth metals. For these materials the electro-spraying technique can be used to give very uniform deposits. A small amount of highly concentrated radioactive solution is diluted with ethanol. The mixture is filled into a drawing pen (with a capillary tip) which is mounted several centimetres above the source mount. In the present device, a potential of 5 kV is connected to the capillary and an annular collimator at about 1 kV is used. The source mount itself is at ground potential and rotates during spraying. Under proper conditions, the drops drawn from the capillary by the electric field are small enough for the solvent to evaporate before reaching the source mount. A special apparatus in which distances and voltages could easily be varied was built by the mechanical workshop. Sources of low-absorption for beta-particles generated by barium and strontium have been prepared.

3. NEUTRON FLUENCE MEASUREMENTS

The laboratory participated in the preparation of the Technical Annex of the Recommendations for Neutron Irradiation of Seeds. A short but practicable prescription for neutron fluence measurements at low intensi- ties was given, and practical aid has been offered to the laboratories participating in the Neutron Seed Irradiation Programme. The laboratory, started the production and distribution of sulphur pellets containing 32 P as recommended for this calibration. The pellets were produced by pressing a known amount of sulphur powder containing 0. 5% of pure graphite into tablets of 1. 00 + 0. 01 cm diameter and of about 3 mm thickness. The irradiated sulphur pellets are calibrated by counting them in a proportional counter. Three different methods were used for the calibrations.

(a) Mixing of a calibrated 32P-solution with sulphur powder, drying and pressing pellets of the same geometry. (b) Bremsstrahlung counting of irradiated pellets enclosed in a box ' made of inactive sulphur using a stabilized gamma spectrometer. The efficiency was determined by counting 32P-sources of known activities between sulphur pellets of various thicknesses and integrating over the thickness of the real pellet. 8 II. MEASUREMENT AND ANALYTICAL METHODS

(c) Simultaneous irradiation of sulphur pellets and ammonium sulphate pellets of the same geometry. The latter ones were dissolved, and the induced activity determined by a liquid proportional counter.

The agreement between the methods (b) and (c) is excellent, the calibration factor obtained with method (a) is higher by 2. 4%. The laboratory offered sets of three unirradiated and two 32 P-containing calibrated pellets to the members of the Study Group on Co-ordination of Re- search on the Use of Neutrons in Seed Irradiations at their meeting in December 1967. The unirradiated sulphur pellets are for irradiation in the given facility, with subsequent counting in well-established local equipment which has been standardized against the 32P-containing pellets measured at the IAEA Laboratory. This enables intercomparison of neutron fluence values for the different irradiation facilities. Those which lack equipment for counting the pellets can, after irradiation, return these to the IAEA laboratory. Calibrated pellets were also sent to the Thailand Atomic Energy La- boratory, Bangkok and to the Department of Botany of the Philippine Atomic Energy Commission. The IAEA-panel on "In-pile Dosimetry" recommended intercalibration of threshold detectors in spectra comparable to the fission spectrum 1. The EURATOM CBNM (Central Bureau for Nuclear Measurements) has started a somewhat different intercalibration of threshold detectors and fast neutron spectra in the reactors of EURATOM- member countries. Through the courtesy of the CBNM a limited number of laboratories outside the EURATOM countries were able to participate via the IAEA laboratory. The detectors made available to the laboratory have already been sent back after the irradiation to CBNM for counting. The detector foils will be returned to the participants together with a set of activity standards for checking their counting facilities. The laboratory itself has participated in co-operation with the ASTRA-reactor of the Osterreichische Studien- gesellschaft fur Atomenergie. This intercomparison will be very useful for the planned distribution of calibrated detectors for fast neutron spectra determinations in thermal reactors.

4. RADIATION DOSIMETRY

4.1. Calorimetric measurements

By request the IAEA calorimeters were taken to Radiotherapy Institutes in Leuven (Belgium) and Vienna (Austria). Absorbed dose measurements in carbon and other materials were made in beams of 60Co 7-rays and betatron electrons. Following the invitation of the National Physical Laboratory in Teddington (UK) comparison measurements were made in a carbon phantom. In the beam of the NPL 2 MeV Van de Graaff machine the National Standard

1 In-pile Dosimetry, Technical Report Series No.46, IAEA, Vienna (1965). VIENNA AND SEIBERSDORF 9 chambers (made from graphite) were compared with the IAEA carbon calorimeter. Data of interest for the conversion of exposure into absorbed dose are derived from these measurements. The reliability and accuracy of such experimental data is higher than those of calculated values, which cannot take into account the spectral distribution of the radiation in the absorbing medium. A paper is in press giving the results of 60Co gamma-ray exposure and absorbed dose measurements in carbon of nuclear purity.

4.2. Ferrous sulphate dosimeters

Upon request from interested institutes, ferrous sulphate dosimeters in Mix-D phantoms were distributed to 19 institutes in 10 Member States (Table II). The purpose of this dosimetry intercomparison was to check the present state of 60Co Y-ray dosimetry. After evaluation in the IAEA laboratories it was found that most institutes irradiated with doses lower than requested. The standard deviation from the mean was about 4%. The method used for this postal intercomparison of ferrous sulphate dosimeters has been described2.

4.3. LiF thermoluminescent dosimeters

The postal absorbed dose intercomparison project using LiF thermoluminescent powder was carried-out as described in the previous report3. The 19 participating institutes received five sets of LiF capsules, each set consisting of two control capsules and three test capsules. One control capsule of each set was irradiated at the IAEA to a known dose before mailing (Tables IITand IV). The participating institutes were requested to give a dose of 500 rad to one test capsule at a time using their 60Co teletherapy beam equipment and following their own method of dosimetry as exactly as if treating a patient,, the capsules being at a depth of 5 cm in a water phantom supplied by the Agency. Information obtained from the participants showed that a variety of methods of dose determination were followed by the different institutes. Furthermore, there were some remarkable differences in the factors used in the dose calculations, e.g. , values of the rad/R factor ranged from 0. 957 to 1. 000. The reliability of this particular method' of intercomparison was proved to be adequate for the present purposes, as indicated by the r.m.s. deviation of 1.4% found for all the 56 irradiated control capsules taken together. The average of the r.m. s. deviations computed for each institute separately was 2.3%, only slightly larger than that of the irradiated controls, indicating that on the whole the institutes are self- consistent. The r.m. s. deviation of the mean of the individual institutes from the mean of all institutes was 4%, indicating that overall agreement was reasonably good. The extreme range of differences from the mean

2 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No. 77, IAEA, Vienna (1967) p. 10.

3 SANIELEVICI, A., NAGL, J., Dosisvergleichsmessungen fur hochenergetische Elektronen mit Eisensulfat-Dosimeter, Strahlentherapie 133, 4 (1967) 561-66. 10 II. MEASUREMENT AND ANALYTICAL METHODS

TABLE II. FERROUS SULPHATE DOSIMETER TEST: PARTICIPATING INSTITUTES

Institute Country

Royal Adelaide Hospital, Adelaide Australia

Manitoba Cancer Treatment and Research Foundation, Winipeg Canada

The Ontario Cancer Institute, Toronto Canada

The Ontario Cancer Treatment and Research Foundation, Ottawa Canada

Institut Gustave-Roussy, Villejuif France

Karolinska Sjukhuset, Stockholm Sweden

Radiofysiska Institutionen, Lund Sweden

Regionsjukhuset, Orebro Sweden

Christie Hospital and Holt Radium Institute, Manchester UK

The General Infirmary, Leeds UK

The London Hospital and Research Laboratories, London UK

Regional Medical Physics Department, Sheffield UK

Royal Marsden Hospital, Sutton, Surrey UK

Westminster Hospital, London UK

M. D. Anderson Hospital and Tumor Institute, Houston, Texas USA

Argonne Cancer Research Hospital, Chicago USA

Lovelace Clinic, Albuquerque, New Mexico USA

Memorial Hospital, New York, N. Y. USA

Temple University Hospital, Philadelphia, Pennsylvania USA

was however over 13%, a surprisingly large disagreement between well- established institutes using 60Co beams. The handling and mailing procedures of the capsules proved to be simple and relatively trouble-free. Two further intercomparisons are being carried out at present, one involving 15 institutes in the Far East, and another with 16 institutes in Canada. These will provide some additional experience with the operation of the system, and will be useful in guiding the future activities of the Dosimetry Section in this field. VIENNA AND SEIBERSDORF 11

TABLE III. NUMBER OF CAPSULES AND TYPE OF POWDER SENT TO EACH INSTITUTE

Purpose Powder Set 1 Set 2 Set 3 Set 4 Set 5 Total

CONTROL Virgin 1 1 1 0 0 3

unirradiated annealed 0 0 0 1 1 2

CONTROL Virgin 1 1 1 ' 0 0 3

unirradiated annealed 0 0 0 1 1 2

TEST Virgin 2 3 2 1 0 8

annealed 1 0 1 2 3 7

5. ANALYTICAL CHEMISTRY (Reference materials)

This work is aimed, as previously reported4, to provide interested Member States with reliable reference materials for checking analytical procedures involved in the production of uranium oxide from low-grade uranium ores.

5.1. Analysed low-grade uranium ores

The four different low grade uranium ores are now available on demand. The samples comprise two torbernites of different origins (Australia and Spain), carnotite (USA) and uraninite (Australia). The uranium content and general composition are available and so far 40 sets of four and single samples of individual ore have been issued. Gamma ray scans and the approximate thorium content have also been determined.

5.2. Analysed sample of uranium oxide containing trace impurities

The inhomogeneity of the supply of this sample was noted in the last annual report4. On a small scale, hand grinding improved the situation, but attempts to use a ball-mill with aluminia cylinders in a porcelain cylinder with the material in the "as stored" condition, after drying for some hours at 120°C, or as a slurry in methanol ethanol mixture, did not produce promising results due to severe caking and to attrition of the grinding cylinders. Other techniques on a small scale, such as freeze drying of concentrated uranyl nitrate solution, spray drying of uranyl nitrate in aqueous

4 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No.77, IAEA, Vienna (1967) p. 15. 12 II. MEASUREMENT AND ANALYTICAL METHODS

TABLE IV. LITHIUM FLUORIDE INTERCOMPARISON RESULTS3

Irradiated CONTROL CAPSULESb TEST CAPSULES Institute (Individual values in Extreme r. m. s. Difference Number % of overall mean) difference deviation from mean m C7°) (%)

20 100.1 101.2 100. 7 5.8 1.7 -2.0

21 101.5 100. 0 99. 3 5.0 1.8 - 7.4

22 99.6 98.5 101. 1 4.9 1.5 + 2.1

24 99.7 98.2 100. 1 5.9 2.4 -0.6

25 99.5 - - 2.8 1.0 -8.3

26 98.7 101. 0 100. 7 7. 0 2.0 -2.3

21 100.6 96.3 101. 3 8.6 2.4 + 1.8

28 100.8 102.8 99. 7 2.8 1.0 + 1.0

29 98.9 99.6 100. 5 7.0 2.3 + 0.4

30 100.4 97.9 99.6 9.9 1.0 + 4.2

39 99.6 - - 5.1 1.6 + 3.5

31 101.1 98.1 - 4.4 1.0 + 4.0

32 100.2 - 99.8 6.4 2.0 - 1.1

33 99.8 101.8 99.4 5.6 1. 7 -2.2 34 100. 5 97.4 100. 5 5. 3 1.7 + 1.1

35 100.8 - - 9.9 3.2 0.0

36 97.4 - - 5.2 1.5 -2.3 37 100.5 102. 8 99. 6 7.2 2.3 + 6.0

38 100. 5 101. 8 96. 7 6.6 2.0 + 1.5

r. m. s. deviation = 1. 4% Average r. m. s. deviation = 1.8% a fuller account of the experiments will appear in: PFALZNER, P. M. , MALO ALVAREZ, S. , lntercomparison of absorbed dose in cobalt-60 teletherapy using mailed LiF dosimeters. Acta Radiologica (in press, 1968). b The unirradiated controls in all cases gave readings which were less than 1°]o of those of the irradiated test capsules.

solution, extraction of uranium and impurities into an organic solvent with rapid precipitation of all components have been tried, so far without success. The studies continue. III. SERVICES TO MEMBER STATES AND TO INTERNATIONAL ORGANIZATIONS5

1. AUSTRIA

Promethium-147 in urine

A request was received from an Austrian Government Office to assist in t)ie determination of the promethium-147 body burden of a worker in the luminous dial industry. In the case of this nuclide, determination by whole-body counting is difficult due to its almost negligible gamma emission, and the low energy of its beta radiation which does not give rise to much bremsstrahlung. Very little literature exists on the determination of rare earth elements and, in particular, of promethium in the human body. The permissible body burden is, however, fairly high so that a small fraction of it can be expected to be detected in urine without difficulty. An analytical scheme was worked out, and consisted of mineralization of the urine, extraction of the promethium with TTA in the presence of lanthanum carrier, back-extraction into nitric acid and precipitation of the rare earth oxalates with excess oxalic acid. By using a known quantity of oxalic acid and titrating the amount left in the filtrate with potassium permanganate, a determination of recovery is also possible. The rare earth oxalates can be counted with an end-window GM counter; however, in view of the low beta energy of promethium-147 (0. 23 MeV maximum energy), a gel scintillation counting method was preferred. The precipitate was slurried with the scintillator in dioxane and mixed with the gel- forming agent. Counting efficiency was found to be 80%, chemical recovery near 100%.

2. PERU

Determination of radionuclides in milk and air filters

A few samples of dried milk and 21 dust samples on compressed- plastic air filters were received from the Junta de Control de Energia Ato'mica, Peru. The milk samples were analysed for strontium-90 and caesium-137 using routine methods. For the air samples, which consisted of fairly considerable solid blocks of organic material in which plutonium-239 had to be determined, a somewhat modified plutonium procedure had to be used: it embodied fusion of the pre-ashed material with potassium pyrosulphate, reduction of the dissolved plutonium to the tetravalent state with hydroxylamine, followed by oxidation to hexavalent plutonium with sodium nitrite, adsorption on an ion-exchange resin (Dowex-1) from strong nitric acid solution, elution with a dilute mixture of hydrochloric acid and hydrofluoric acid, evaporation on a Teflon dish,

5 Available by request.

13 14 III. SERVICES TO STATES AND ORGANIZATIONS and alpha-measurement in a window-less proportional counter to a precision of + 5%. This method is a modification of a method used at AERE, Harwell6.

3. SOMALIA

Analysis of mineral samples

Two composite samples were received from a UN sponsored geological survey in Somalia with a request for analysis for uranium, thorium, yttrium, yttric earths and ytterbium. As requests for analysis of mineral samples for uranium and/or thorium have risen, a more systematic study of the problems will be'made, aiming at greater sensitivity, particularly for thorium.

4. SUDAN

Determination of beta activity

The determination of gross radioactivity on gummed paper samples sent to the laboratory by the Ministry of Communication of the Republic of the Sudan was continued7.

5. TUNISIA

Determination of uranium in ores

Rock samples with a probable content of uranium were received from a Technical Assistance expert on prospecting. Comparison of the gamma-spectrum with an uranium ore of known content showed the spectra to be identical and the uranium content to be 0. 26 + 0. 02%, assuming equilibrium between uranium and radium. Attempts to check this with a Li-drifted germanium detector failed. The uranium content was further checked by X-ray fluorescence when a value of 0. 22 ± 0. 01% was obtained (Figs 3-5).

6. UN FOOD AND AGRICULTURAL ORGANIZATION

Applied neutron activation analysis: determination of mercury in pesticide residues

At a FAO/WHO Panel on Pesticide Residues hold at WHO Headquarters, Geneva, November 1966, the analytical requirements for the assessment of these residues in food and biological materials were discussed. In some cases the tolerance levels are so low that the limits of detection of the

6 EAKINS, J.D. , GOMM, P.J., Symposium on the determination of radionuclides in materials of biological origin, AERE, Harwell, 20-21 April 1967. IAEA Laboratory Activities, Fourth Report, Technical Reports Series No.77, IAEA, Vienna (1967) p.27. VIENNA AND SEIBERSDORF 15

o o c\ N*

TUNISIAN ORE "g . 3'

Tobernite standard

0.3 % U3 06 , 11 g, 3'

£ Q. 235 U 2.5 mg , 2'

C o u

Ra - standard 2x10* dpm, 0.2'

U30e Merck 50 g ,0.5'

( 2000 Energy (KeV) • FIG. 3. Gamma spectra measured with a 3 X 3 in. Nal(Tl) well-type ciystai (a) uranium ore sample from Tunisia (d) radium standard

(b) IAEA reference sample S2 (Torbenite, 0,313% U308) (e) uranium oxide (Merck) (c) uranium-235 16 III. SERVICES TO STATES AND ORGANIZATIONS

tt t t t t

FIG. 4. X-ray fluorescence spectra (obtained with W tube, LiF crystal and scintillation counter).

(a) IAEA reference sample S2 (Torbenite, 0. SlS^o U308) (b) NBL analysed sample No. 75 (0. 05% U) (c) Uranium ore sample from Tunisia

existing methods of analysis based on the classical approaches are inade- quate and it is necessary to improve these existing methods or develop additional ones. Particular attention was given to neutron activation and isotope dilution techniques in this field. At a meeting on Neutron Activation Techniques in the Life Sciences held in Amsterdam in 1967 the problem was again considered and sug- VIENNA AND SEIBERSDORF 17

in sample % (j added

FIG. 5. Calibration curve for uranium determination by the addition method. The concentration of uranium in the sample is determined by extrapolating the curve obtained by measuring the count rates for the sample both with and without addition of known amounts of uranium standard. gestions were made that the Agency should assist workers in this field by including pesticide residue samples, in particular mercury compounds, in its Low-level Radioactivity Quality Control (LOWRA) Programme. This suggestion was taken up by the Agency's laboratory and a number of different samples containing such residues was included. In the course of the analysis of these samples at the Agency's laboratory, a neutron activation method for the determination of mercury in the parts-per-billion range was worked out. The method is based on the amalgam exchange method of De Voe, Kim and Meinke8. This method, originally developed for the analysis of metals which form amalgams with mercury, was also found to yield promising results in the analysis for mercury itself. The main step is the equilibration of an acidic aqueous mercury solution containing activation product mercury-197m, 197 or 203 with excess metallic mercury. In model experiments to try out the method it was found unnecessary to use ultrasonic equipment to produce the required intimate contact between the aqueous and the metallic phases in the heterogeneous system, a simple laboratory-type motor-driven shaker did a satisfactory job in a few minutes. Details of the method as applied to organic systems are still being worked out.

8 De VOE, J.R., KIM, C.K., MEINKE, W.W., Talanta 3 (1959) 298. IV. CHEMICAL AND PHYSICO-CHEMICAL INVESTIGATIONS RELEVANT TO THE AGENCY'S PROGRAMME

1. LOW-LEVEL RADIOACTIVITY (LOWRA) QUALITY CONTROL PROGRAMME

The purpose and the overall importance of this programme have been discussed in the previous Report9. Information on further developments and achievements during 1967 is given below.

1.1. Methods of analytical quality control

The results of analytical procedures are subject to random and systematic errors. Random errors can be detected by repetition of analysis. Precision, therefore, can readily be quoted but gives no indication of the over-all error involved. Unfortunately, precision is often the only information available. Accuracy is' influenced by systematic errors, the detection of which requires more complicated methods, such as:

(a) analysis to be carried out by as many independent methods and equipment as possible. In case where the agreement is good, results are assumed to be accurate;

(b) control analysis of reference material, i. e. material of certified composition which is as similar as possible to the samples to be determined under routine conditions. Agreement between certified and observed values is a direct measure of the accuracy for the particular type of analysis;

(c) participation in interlaboratory comparisons. Samples used in these intercomparisons should be as far as possible similar to those to be analysed under routine conditions. The agreement of the results of a particular laboratory with the most probable value is a measure of the accuracy of the type of analysis under investigation.

1.2. The present situation in analytical quality control

Excellent analytical quality control schemes exist for technical and industrial analyses. These branches of applied analysis are well aware of the difficulties and pitfalls existing in analysis and maintain a very strict and comprehensive internal quality control programme. In addition hereto, national organizations are providing extremely useful analysis quality control services by offering a great number of reference materials which, however, cover mainly industrial and technical types of analysis. Thus, the reliability of these analyses is known sufficiently well for the need to which they are applied. The reliability of results in other branches

9 IAEA Laboratory Activities, Fourth Report, Technical Report Series No.IT, IAEA, Vienna (1961) p.11.

18 VIENNA AND SEIBERSDORF 19

of applied analysis is often not so satisfactory. This has been shown by the results of numerous intercomparisons in various fields of applied analysis. It has turned out that the accuracy is only partly in line with the requirements set by the purpose of analysis and that it is not as high as could be achieved easily under normal routine conditions. This is due to one or more of the following factors :-

(a) internal analytical quality control measures can only be taken by a limited number of institutes as resources may be available for one method only; (b) reference material is not generally available and can be prepared only in exceptional cases by the institutes themselves; (c) intercomparisons are organized rather seldom and, so far, many important types of analyses have not been covered.

This means that the majority of laboratories are not in a position to maintain an effective analytical quality control scheme.

1.3. Analytical quality control in applied radiochemical analysis

With the increasing use of nuclear energy for peaceful purposes the problem of possible environmental contamination becomes more acute and radiochemical analysis gains in importance. Radionuclide applications are likewise based on results of radiochemical analysis. However, only a small fraction of the laboratories engaged in routine work in this field at present adequately control the reliability of their analyses. To improve this situation the Agency has, since 1962, organized a series of intercomparisons covering mainly the following two types of analyses, (1) determination of artificial and natural radionuclides and (2) determination of trace elements.

1.3. 1. Determination of artificial and natural radionuclides

The results of intercomparisons evaluated so far have been described in detail in a report10. From the test runs it can be deduced that, on average, the reliability of environmental data is satisfactory for monitoring purposes. A scientific evaluation, however, would in many cases require more accurate results. This applies especially to the more important nuclides such as strontium-90 and caesium-137. A comparison of the results of the major 90Sr, i37Cs and 226Ra runs is highly informative. The normalized results of these runs are given in Fig. 6-8. The analyses have been performed in different types of material for a wide range of concentrations of the radionuclides in question. The figures show that the spread of the results is almost the same in the case of 90Sr and 13fcs determinations, i.e. the reliability of results is almost independent of the level of contamination between 50 and 200 000 pCi/kg. Obviously, proportional errors which might be of random and/or systematic nature dominate in this range. The results of 226Ra determinations in the range of 1 to 100 pCi/kg present quite a

10 The Reliability of World-Wide Monitoring in the Light of Accuracy of Low-Level Radiochemical Analysis, IAEA Report 30 June 1967. 20 IV. CHEMISTRY AND PHYSICAL CHEMISTRY

MILK

50 pCi / kg •lllllll

RICE FLOUR 60 .11,

MIXED DIET jL MO

SOIL 200

VEGETATION LOW

900

J ..lill.

VEGETATION MEDIUM

2700 III

MEAT MEDIUM 11 1600

BONE LOW Jl. 6500

BONE MEDIUM A 200000 0 20 m SO . 60 WO 120 !<0 ISO ISO 200 220 SO0 800 KOO

NORMALIZED RESULTS

FIG. 6. Results of strontium-90 intercomparison runs, 1962-1965. (Individual results normalized with reference to the corresponding probable values taken as 100). VIENNA AND SEIBERSDORF 21

ANIMAL MATERIAL

•100 pCi/kg

MIXED DIET

•350

VEGETATION

•700

MILK '2700

MEAT MEDIUM •60000

20 <0 SO 80 100 120 HO 160 160 200 220 300 <00

NORMALIZED RESULTS

FIG. 7. Results of caesium-137 intercomparison runs, 1962-1965. (Individual results normalized with reference to the corresponding probable values taken as 100). different picture. There is a good grouping of results in the case of higher concentrations but a considerable spread can be observed with decreasing concentration. This is most probably due to the fact that additive errors of a systematic nature dominate in the latter range which, therefore, cannot be detected by internal measures. This result is well in line with the experience obtained from other intercomparisons in the field of trace analysis. It underlines the need for a regular control of analytical quality in low- and particularly in extremely low-level analysis. The results of the major runs have been treated statistically. The potassium-feldspar exercise is given as an example (Fig. 9). In this run, the total potassium content has been determined by techniques such as mass spectrometry, flame photometry and chemical methods, or by calculation from the results of counting techniques. 22 IV. CHEMISTRY AND PHYSICAL CHEMISTRY

MILK

• 1 pCi / kg

J L I.I I

MIXED DIET

J_i 111111 Lll

VEGETATION •10

BONE

100

0 20 40 60 SO no 120 140 160 180 200 220 240 260 <00 600 BOO 1000

NORMALIZED RESULTS

FIG. 8. Results of Ra-226 intercomparison, 1962-1965. (Individual results normalized with reference to the corresponding probable values taken as 100).

From the individual results reported by the participants, the confidence limits of the mean based (a) on the standard deviation of individual results Xj = x + t0 05 s and (b) on the standard deviation ofthe mean X; = x ± t0 05s have been calculated. The results obtained with classical chemical and physical methods give a rather consistent picture. Variance analysis has shown that there is no significant difference between the results of individual laboratories. The results obtained by counting techniques, however, show a less consistent picture. Similar results have been found in other inter comparisons.

1.3.2. Trace element analysis

Particular attention has been given to the quality control of trace element analysis since trace amounts of elements or compounds may have a considerable influence on the metabolism in plants, animals and man. Deficiencies and unduly high levels are known to be harmful. Determination of the existing levels of an essential or a toxic element is, therefore, an objective of regular monitoring. A wide range of trace elements are, by preference, determined by activation analysis. VIENNA AND SEIBERSDORF 23

IAEA RUN 66/ 5

FELDSPAR Ft f„„S NUCLIDE: K | " *t f0.05 s I *

Various chemical and physical methods 5 p - and. jf- counting

1 2 3 i 7 I 9 10 II 12 13 H IS 18 17 « 19 20 21 21 I 2 3 t It 14 IS IT 2223 LAB. No.

FIG. 9. Results of the potassium feldspar run 1966. Mean values as reported by individual laboratories, with confidence limits based on: (a) standard deviation of the individual results, X ± 10_ 05 s , and standard deviation of the mean, X ± t0.05 s.

Among these, mercury is of great interest as mercury compounds are widely used in agriculture and industry. Due to deliberate or accidental release, small amounts of mercury reach the biosphere and serious poisoning may result from its accumulation. The results of mercury analysis being of public interest, intercomparisons for the determination of mercury in cereals have been organized. The results obtained so far are given in Fig. 10. It can be seen that the accuracies achieved in the determination of mercury-levels in untreated wheat flour and in wheat flour which has been made from mercury-treated grain are rather satisfactory. Serious systematic errors occur in only exceptional cases. The relatively wide spread of results is probably due to the rather small amounts of material, by nature inhomogeneous, used for the individual analyses. Since, however, only experienced laboratories participated in these runs, no general conclusions on the accuracy of mercury determination by neutron activation can be drawn.

2. STUDIES ON DECOMPOSITION UNDER RADIATION

2.1. Decomposition of folic acid

Some studies on the radiation decomposition of folic acid, carried out at the request of the Division of Life Sciences, have already been 24 IV. CHEMISTRY AND PHYSICAL CHEMISTRY

IAEA RUN 66/11

CEREALS: untreated

NUCLIDE: Hg

111

IAEA RUN 66/10

CEREALS: Hg-treated

NUCLIDE: Hg

FIG. 10. Results of the mercury-flour intercomparison 1966 (frequency of occurrence for all results). reported11; the work has been completed by electrophoretic separation of the radiolysis products, using a cellulose column, and by quantitative determination of carboxylated compounds. The electrophoretic separation of radiolysis products showed the formation of a positively charged compound, the chromatographic be-

11 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No.77, IAEA, Vienna (1967) p. 30. VIENNA AND SEIBERSDORF 25 haviour of which indicates a compound similar to 2-amino-4-oxo- dihydropteridine. The irradiation of folic acid in aqueous solution mainly gives rise to the following processes:

(i) Cleavage of folic acid yielding pteridine and p-amino-benzoylglutamic acid.

(ii) Oxidation of the pteridine moiety by OH-radicals and H202 with the formation of carboxylated compounds. (iii) Successive hydroxylation of the pteridine part with the formation of xanthopterine and derivatives. (iv) Oxidation of the p-aminobenzoylglutamic acid leading to the formation of 3-hydroxy-p-aminobenzoylglutamic acid. Further irradiation of folic acid involves a formation of p-aminobenzoic acid and finally of aminophenols.

2.2. 7-sterilization of packaged biomedical products

Two further studies have been made as a part of a programme aimed at exploring the feasibility of 7-sterilization of packaged biomedical products. The radiosensitivity of tetracycline antibiotics was investigated. Various concentrations of oxy- and chloro-tetracycline were exposed to several dose levels of gamma irradiation. Chemical changes were followed by visible and ultraviolet light absorption spectra and by thin- layer chromatography. Microbiological activity was assayed in parallel studies by the agar plaque technique. Both antibiotics were quite resistant to chemical or biological change in activity when irradiated in the solid state or in solutions in organic solvents such as methanol or mercaptoethanol. In aqueous solutions, however, doses as low as 25 krad produced significant inactivation. The electron spin resonance (ESR) spectra show that gamma irradiation of both oxy- and chloro-tetracycline in solid state leads to the formation of free-radicals. For unirradiated oxy-tetracycline no signal was recorded, whereas for unirradiated chloro-tetracycline a small signal was recorded, probably due to a weak spin-spin interaction of the electrons of chlorine atoms with the protons of the neighbouring methyl groups. The ESR data for oxy- and chloro-tetracycline irradiated in solid state at 2. 5 Mrad indicate that the formation of ..mono- or bi-radicals by abstrac- tion of hydrogen atoms occurs during this process. However, the results suggest that the radiosterilisation of tetracyclines in the solid state may prove to be technically practicable.

2.3. The effect of 7-irradiation of human blood-plasma proteins

The effect of gamma (60Co) irradiation on various fractions of human blood-plasma proteins has been investigated. The potential usefulness of employing ionizing radiation to "cold-sterilize" biomedical products has stimulated research on radiation sensitivity of various blood plasma fractions. At doses between 0. 2 and 5. 0 Mrad alpha-isohaemagglutinins were found to be more readily inactivated than beta-isohaemagglutinins, but neither was completely inactivated in this dose range. Sterility, clotting arid anti-haemophilic activity were also assessed on irradiated 26 IV. CHEMISTRY AND PHYSICAL CHEMISTRY and freeze-dried preparations of human plasma. No significant differences were detected.

3. PURITY OF COMMERCIAL RADIOCHEMICAL PREPARATIONS

3.1. Studies on thyroxine

Semi-quantitative results of studies on the purity of 131I-labelled thyroxine from various manufacturers have already been reported113. By using a radiochromatographic scanning apparatus the reliability of results which involve the estimation of total activity contained in the "spots" on the chromatogram has improved. Typical results for two preparations of different origin are shown in Table V.

TABLE V. DISTRIBUTION OF RADIOIODINE IN DIFFERENT CHEMICAL FORMS FOR TWO THYROXINE PREPARATIONS. Chromatogram: thin layer silica gel; Solvent: iso-propyl alcohol/ethyl acetate/acetone/ammonia (6N) (35/30/25/20)

Days after Inorganic Thyroxine Other Analogues Total Item receipt of iodine and Tri- compounds of thyro- organic sample iodothyronine -acetic acid iodine C7») O) 00) (<7o) 07»)

Thyroxine 1 4 70 11 14 95 (A) 14 14 55 12 17 83

21 18 58 15 10 82

27 19 . 45 19 6 70

Thyroxine 1 3 75 8 12 95 (B) 9 11 60 15 13 87

16 17 59 15 15 88

23 17 57 12 16 80

30 13 51 5 6 61

The mechanism of radiolytic decomposition of unlabelled thyroxine and related compounds, under external 7-irradiation, has been investigated. Decomposition was greater in aqueous solution than in the normal solvent for thyroxine, 50% propylene glycol solution. Formation of hydroxylated compounds is the main effect. At high doses, thyroxine splits into phenols

lla IAEA Laboratory Activities, Fourth Report, Technical Report Series No.77, IAEA, Vienna (1967) 31. VIENNA AND SEIBERSDORF 27 and derivatives of phenylpyruvic acid. Irradiation of labelled thyroxine was also studied and it was found that at a gamma dose of 0. 5 Mrads the organic iodine content was reduced to 50%; further irradiation to 1-1. 2 Mrads indicated an almost complete de-iodination of the compound. The main process seems to be the substitution of hydroxyl radicals for the iodine atoms on the benzene ring.

3.2. Studies on 203Hg-containing compounds

Preliminary studies were also carried out on the purity and behaviour under storage conditions of some radio-mercury containing compounds (chlormeridrin and salyrgan) used for brain and kidney scanning to detect tumours. These applications demand high purity products. Commercial samples of these two compounds, labelled with mercury-203, were obtained and analysed periodically by thin-layer chromatography. Analysis shows that salyrgan is more stable with regard to the formation of inorganic mercury ions than chlormeridrin. The analytical method is somewhat complicated, as results are very dependent on the solvent system used. Further work will be necessary. External irradiation of the compounds with gamma radiation also shows salyrgan to be the more stable. At a dose of 0. 5 Mrad, 46% of the chlormeridrin but only 7% of salyrgan, both in solution, were decomposed. Irradiation does not lead however to an increase of the amount of free inorganic mercury in solution, since a precipitate, which is believed to be Hg20, is formed.

4. SAFEGUARDS PROGRAMME

During 1967 one laboratory room has been altered and equipped to enable plutonium in solution to be safely handled allowing analysis of the samples recovered from Safeguards control of nuclear fuel re-processing.

4.1. Analytical standard samples

As part of the procedures for safeguarding the National Fuel Service processing plant at West Valley, New York, standard samples containing known amounts of plutonium and in some cases uranium were prepared which simulated input and output solutions, and also certain waste products. These were analysed by the National Fuel Service Analytical Service to check .the accuracy and precision of their methods, under observation of two members of the IAEA Laboratory staff who acted as Inspectors during the operation on the Yankee Reactor fuel. Plant samples such as the final plutonium product solution and others were also taken to Vienna by the IAEA Inspectors and have been analysed at the Laboratory as an additional control on the analytical procedures.

4.2. Neutron activation analysis

A few samples of uranium oxide of low enrichment were analysed for isotopic composition using a neutron activation technique with barium-140 as the fission monitor. This method was used in the absence of, as yet, a suitable mass-spectrometer. 28 IV. CHEMISTRY AND PHYSICAL CHEMISTRY

4.3. Precise tritium assay

The tritium content of a number of heavy-water samples, obtained from Japan and Norway, have been assayed by liquid scintillation counting. After many tests and alternations the precision is now thought to be better than the desired ± 0.5%. Further results for samples obtained during 1968 will show if the tritium build-up may eventually be used for monitoring the integrated power dissipated in heavy-water moderated reactors.

4.4. Plutonium in urine

In the course of their safeguards inspection of the National Fuel Service plant, the Agency1 s Inspectors were required to work for a considerable length of time in hot areas, possibly contaminated with plutonium. Accordingly, on their return to Headquarters, they were subject to health control procedures, including a medical examination, whole- body counting and urine analysis for plutonium-239. For the latter the following method was used: A 24-hour urine sample was heated with concentrated nitric acid, the plutonium was co-precipitated with calcium phosphate by addition of ammonia, converted to the trivalent state and adsorbed on a Whatman GFA glass fibre filter. After elution, it was measured either without further purification, or after purification by ion exchange. Sources were prepared by evaporation and flaming on a platinum dish, or by electrodeposition on a steel platelet. All these variations were tried and were found to give satisfactory and comparable results. Recovery of plutonium in model experiments was found to range between 80% and 85%. Even with quite unsophisticated counting equipment consisting of an open-window methane-flow proportional counter and a manual sample changer, a detection limit of 0. 2 pCi of plutonium could be achieved which, when present in a 24-hour sample, is assumed to correspond to 5% of the maximum permissible body burden for plutonium. V. NUCLEAR TECHNIQUES IN HYDROLOGY

The primary aim of the IAEA Laboratory work in this field is to make • available analytical services for the provision of data required for the application of isotope methods in the Agency Programme for Water Re- sources Development. This includes the IAEA/WHO network for determination of tritium in precipitation, the International Hydrological Decade and UNDP Special Funds Projects.

1. TRITIUM

The enlarged overall capacity of the tritium laboratory made possible the gas counting of 1500 samples in 1967 (excluding background checks and calibration samples). Further experiments were carried out for increasing both the total capacity and lower detection level of tritium.

1.1. Enrichment by electrolysis

A new set of 20 cells has been added to the existing system of 16 cells, resulting in an increase of the number of samples enriched per week. The reproducibility checks performed on both electrolytic systems have shown a reproducible coefficient of variation between individual cells of ±3%. The standard electrolysis run of one batch requires 3 days, resulting the volume reduction factor of 22 and a tritium enrichment factor of about 15. Two experimental runs were made with the system of 16 cells in which an additional 200 ml of water sample were added to each cell after the residual volume was about 15 ml. The total enrichment factors of these ' double runs' were about 32 and the coefficient of variation was ± 3%.

1.2. Isotope fractionation from distillation

Further experiments were performed to establish the isotope fractionation effect during distillation before and after electrolysis. It was confirmed that during the routine initial distillation the tritium concentration of the distillate is affected by fractionation by less than 1% provided that not more than 10% of the initial volume of the sample is left undistilled. In the final distillation, isotopic fractionation due to either the conditions of distillation or to the formation of sodium hydroxide has not been detected.

1.3. Gas counting

The routine gas sample preparation is unchanged and four gas counters are being routinely used for tritium counting. The detailed examination of possible contamination and memory effects during preparation of the gas samples has been performed and the following conclusions have been drawn:

29 30 V. HYDROLOGY

(a) Magnesium furnace (used for hydrogen preparation from the water sample). It has been found that proper outgassing at a high temperature eliminates tritium contamination from the fresh magnesium filling. A memory effect varying between 0. 1% to 0. 5% has been observed by running 'dead' water or low-activity samples through the furnace after very high activity samples.

(b) Molecular sieve (used for storing hydrogen gas). No significant memory effects have been observed. A dead water sample put through the sieve straight after two samples of 104 T.U. activity showed no measurable contamination.

(c) Palladium-catalysts. No memory effects have been observed; however, the fresh catalyst indicates an initial contamination of 5-20 T.U. As a rule the first background sample run through the fresh catalyst is discarded; the second one does not show measurable contamination.

1.4. Preparation of n-butane for tritium gas counting

The electrolytic enrichment of tritium in water samples usually ends up with an enriched sample volume of about 11 ml. One half of this amount is converted to ethane using a two step process. At first 5 ml of the water are reduced to 6 litres of hydrogen over hot magnesium and then ethylene is combined with 90% of the stoichiometric hydrogen amount over a palladium-asbestos catalyst to produce about 6 litres of ethane. The ethane goes into a proportional gas counter of about 2. 5 litres volume at two atmospheres filling pressure. In order to measure a bigger sample in this counter, either the working pressure must be increased to over two atmospheres, or a hydrocarbon with more 1 sample" hydrogen in the molecule should be synthesized and used. The possibility of incorporating more than one hydrogen molecule into the hydrocarbon seems to be attractive. Different authors report the formation of methane from carbon dioxide and water12, the hydrogenation of acetylene to ethane13, and of propyne to propane14. Using one of these methods the amount of sample hydrogen in the counter could be doubled, but an unsaturated hydrocarbon which combines with three molecules of sample hydrogen or even more would be even more desirable. The resulting hydrocarbon must be a gas at 2 atmospheres pressure. Two unsaturated hydrocarbons have been considered: diacetylene or 1, 3-butadiyne and vinylacetylene or 3 butene-1-yne. The hydrogenation of both compounds will yield n-butane

CH = C - C = CH + 4H2 ^^ J^l CHg ~ ^Hg - CHg - CHg

CH2 = CH-C = CH + 3H2

Hydrogenation experiments on diacetylene using 90% of the stoichiometric hydrogen amount with a palladium-asbestos catalyst resulted in a quantitative

12 ANAND, J.S., LAL, D., Nature, Lond. 201 (1964) 775. 13 BAINBRIDGE, A.E. et al., Science 134 (1961) 552. "EULITZ, G.W., Rev. Sci. Instrum. 34 (1963) 1010. VIENNA AND SEIBERSDORF 31 reaction of the hydrogen. The formation of noticeable amounts of liquid polymers, however, does not make this reaction suitable for our purpose. Vinylacetylene was hydrogenated over palladium on asbestos with 90% of stoichiometric hydrogen. The hydrogen reacted quantitatively with this hydrocarbon, and there were less polymerization products than with diacetylene. This reaction shows promise and should be investigated further. The economics of the process and the availibility of vinylacetylene must also be considered.

1.5. Liquid scintillation counting

Recent investigations into the use of the non-ionic detergent Triton X-100 (Rohm and Haas trademark) as emulsifying agent for water-toluene samples to be assayed by liquid scintillation counting prompted a comparison of the system with that based on dioxane-naphthalene as solvent. The results, presented at the Symposium on Radioactive Dating and Methods of Low-level Counting15 held in Monaco 1967, showed that the Triton system was superior. Further investigations, to be published in the near future, have led to the specification of an optimum mixture as follows: 30% water, 70% scintillator solution consisting of 35% Triton, 65% toluene, the mixed solvent containing 7. 0 g/1 PPO and 0. 5% g/1 POPOP. Counting efficiency in the Packard model 3002 spectrometer with this mixture (samples of 25 ml total volume in polyethylene vials) is 15.5%, corresponding to 120 T.U./cpm (background count rate is 10 cpm). The dioxane system was reinvestigated and the optimum mixture found to consist of 20% water and 80% dioxane containing 100 g/1 naphthalene, 7. 0 g/1 PPO and 0. 6 g/1 POPOP. With this mixture (25 ml sample volume in polyethylene vials) counting efficiency is 12.9% corresponding to 215 T.U./cpm (background count rate 9. 0 cpm). Reproducibility of results and ease of sample preparation are about the same for both systems.

2. CARBON-14

The routine procedure for determination of 14C in water, as described in the previous report is being continued16.

3. SCANDIUM-46 LABELLED COMPOUNDS AS TRACER FOR WATER

There is a need for water soluble compounds of gamma-emitting isotopes for use as a groundwater tracer. The major difficulty is the adsorption of the compound by the soil or by components of the soil. The adsorption of scandium ethylene diamine tetracetate (EDTA) and diethylenetriamine-pentacetate (DTPA), two very stable water soluble metallic chelates, on common separated soil components has been investigated both in batch and in continuous column experiments. The

15 WILLIAMS, Pamela H., FLORKOWSKI, T. , Radioactive Dating and Methods in Low-level counting (Proc. Symp. Monaco, 1967), IAEA, Vienna (1967) 703. 16 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No.77, IAEA, Vienna (1967) p. 74. 32 V. HYDROLOGY scandium compounds were labelled with scandium-46, a strongly gamma emitting isotope of 84 days half-life. Batch experiments showed that neither compound (0.5 /ug/gm solution was adsorbed at pH-7 on quartz sand (the reference material) or kaolin

(Kj = 0), but both were adsorbed to some extent on bentonite (Kd ~ 0. 75). Column experiments were carried out with packings of pure quartz sand and mixtures of 90% sand plus 10% of other minerals to a depth of 50 cm. Flow rates of 40-45 ml/h were used and the effluent collected in a fraction collector. Dual tracers were used, the purified labelled scandium'compound and tritiated water. Neither scandium compound was adsorbed on pure quartz sand; recovery was complete both for scandium-46 and tritium and the elution curves for both were identical. The recovery of scandium EDTA from a 90% sand -10% kaolin column was 97% as against 99% for tritium, while in the case of the DTPA compound 99% was recovered as against 97% for tritium. These results are probably identical within the experimental error. It was noticed however that the DTPA compound was retarded slightly with respect to the tritium movement. Other minerals will also be investigated and studies of the effects of dilution and pH-value will be carried out.

4. OXYGEN ISOTOPIC COMPOSITION

The Russian mass-spectrometer model MI 1305 has been equipped with a double collector system, designed and built at the laboratory, and balancing circuits for the determination of isotopic ratios of slightly differing values. A double channel gas inlet system was added and a thermostatic system for isotopic equilibration between water samples and gaseous carbon dioxide was constructed. The instrument is now ready for the precise determination of natural variations in the isotopic content of oxygen for hydrological purposes. VI. NUCLEAR TECHNIQUES IN MEDICINE

The laboratory programme in the medical applications of nuclear techniques has continued along the pattern of previous years with emphasis on: (1) development of methods and instruments to increase the usefulness of radionuclides in medical diagnosis and research; (2) support of other activities in the Agency1 s laboratory; (3) assistance to particular laboratories in Member States; and (4) conduct of investigations having special relevance to the Agency's interests. The activities within each of these areas are summarized in turn below.

1. DEVELOPMENT OF METHODS AND INSTRUMENTS

1.1. Medical activation analysis

A collaborative programme is being established between the Agency's laboratory, laboratories in a number of Member States, and WHO, to collect data on mineral element metabolism in humans suffering from protein-calorie malnutrition and/or cardiovascular disease. The occurrence of these elements in representative tissues will be determined by neutron activation analysis. Techniques are being developed in the laboratory mainly for assay by gamma-ray spectrometry; avoidance of chemistry where possible will increase the throughput of samples and reduce the possibilities of error. The equipment available consists of two gamma-ray spectrometers. The first, a 2-parameter pulse height analyser, has been described in previous reports17. The second uses a refrigerated coaxial Ge(Li) detector of 20 cm3 volume. Spectrometers of the latter type show great promise in activation analysis because of their excellent energy resolution. An important share of the medical activation analysis programme during 1967 has been devoted to setting up of this instrument and to investigations of its performance. The important parameters defining the performance of the detector are its photopeak efficiency, energy resolution, peak-to-Compton counting rate ratio, linearity of channel number vs. photon energy, and stability. Typical values found for these parameters are listed in Table VI. In addition, the variation of counting rate with height of sample in a sample vial has been determined for all source geometries and gamma-ray energies anticipated; it is independent of energy. Resolution is greatly influenced by the electronic system. Variations in equipment conditions have been systematically explored for a wide range of counting rates using several borrowed amplifiers. The best overall performance has been achieved with an existing amplifier after suitable adjustment of time constants in the pre-amplifier and amplifier. With regard to stability, temperature fluctuations have been found to cause a ± 0.3% change in overall gain, with consequent significant degradation

17 IAEA Laboratory Activities, Fourth Report, Technical Report Series No.77, IAEA, Vienna (1967) p. 60.

33 34 VI. MEDICINE

TABLE VI. CHARACTERISTICS OF 20 cm3 Ge(Li) DETECTOR

Parameter Typical Values

Photopeak efficiency 7.8% at 122 keV (5^Co)

(Point source at 1.7% at 279 keV (203Hg)

position of max. 0. 45% at 662 keV (137Cs)

count-rate) 0.11% at 1832 keV (MY)

Energy resolution 6.1 keV at 1333 keV ("Co)

Peak/Compton ratio 4. 7 at 1333 keV (®Co)

Stability ~ 0.05% changes in system gain

under conditions of good ambient

temperature stability.

Linearity Smooth function of energy; de-

viations of up to 4 channels

(in 1024) from "expected" peak

. positions.

Pulse pile-up equivalent to ~ 0.1% increase

in system gain for ^Co at 40%

dead-time.

of photopeak resolution. A spectrum stabilizer, similar to the one described in previous reports but stabilizing on a peak within the experimental spectrum, has been constructed and its use overcomes this difficulty. At the IAEA Symposium on Nuclear Activation Techniques in the Life Sciences (Amsterdam, May 1967), doubt was expressed (Proceedings, p. 79) regarding the linearity of superposition of spectra from two or more radionuclides measured simultaneously. However, experience with the above detector has shown that superposition is in fact linear. There- fore, except in rare cases where the peaks are not completely resolved, the activities of individual nuclides in a mixture can be reliably deduced VIENNA AND SEIBERSDORF 35

FIG. 11. Gamma-ray spectrum of a complex mixture of radionuclides measured with a Ge(Li) detector. The Cs-137 peak is marked with an arrow. from the photopeak areas measured above a straight line fitted to the continuous spectrum at the base of the peak. As an example, Fig. 11 shows a composite spectrum recorded from a mixture of radionuclides including 137Cs (photopeak marked with arrow) at a high counting rate 137 (dead time =50%). The Cs activity was calculated by the above procedure with an error of 1.8%, compared to an expected standard deviation of 1.2% from counting statistics alone. A computer programme has been written to perform the large amount of calculation foreseen in the reduction of data collected with the Ge(Li) detector on many samples. The programme computes photopeak areas by the method outlined above, takes ratios relative to appropriate standards, corrects for radioactive decay between the time of measurement of the sample and the standard, allows for the dependence of counting rate on the height of sample in the vial, and prints out the concentration of each element in parts per million. To provide some of the supplementary data required beyond the pulse-height spectrum in these calculations, a "manual entry system" has been designed which permits numerically coded information to be incorporated automatically into the record of a measurement. The overall accuracy and precision of neutron activation analysis is determined not only by the measurement of the induced activities but also by the homogeneity of the activating neutron flux. The latter has given rise to some problems in irradiating samples at relatively low integrated fluxes (~ 5. 1014 n/cm2). Inside the pneumatic tube facility that is available at the Austrian Seibersdorf reactor for short irradiations, variations in integrated flux (maximum to minimum) amounting to approximately 13% were observed. To reduce these differences a rotatable sample holder was constructed that can be inserted in an irradiation channel where the thermal flux is approximately 1011 n/cm2 sec. After initial difficulties, it has been found possible to reduce to less than 2% the variation of integrated flux among all samples in this holder. 36 VI. MEDICINE

/ 2 3 V S 6 7 8

FIG. 12. Gamma-ray spectrum from neutron activated human liver shortly after activation. The numbered peaks are associated with the following radionuclides: (1) 511 keV annihilation radiation, partly from 61 Cu; (2) »°Br and MC1; (3) 56Mn; (4) MC1; (5) !

FIG. 13. Gamma-ray spectrum from activated human liver several weeks after activation. The numbered peaks are associated with the following radionuclides: (1) 86 Rb; (2) 5®Fe; (3) s5Zn; (4) 60Co; (5) 5'Fe; (6) "Co. Current practice in the activation analysis work with the Ge(Li) detector is to irradiate each sample to an integrated flux of ~ 5. 1014 n/cm2 for determination of Na, K, CI and Mn. A typical spectrum is shown in Fig. 12. A further irradiation is then given to raise the integrated flux to ~ 5. 1017 n/ cm"2. After a decay of 10 days, numerous peaks from 82Br can be identified and measured. Further decay of one or two weeks allows measurement of Rb, Zn, Fe and in certain cases Co (Fig. 13). Ad- VIENNA AND SEIBERSDORF 37 ditional elements can be measured with the 2-parameter Nal(Tl) spectrometer as described in the previous report. The medical activation analysis programme has also included investigations of an instrumental method for determining selenium based on the use of 19 second 77rnSe, and of the use of the Ge(Li) detector as a pair spectrometer. A measurement of copper in a liver biopsy sample from one of the Vienna hospitals was carried out to aid in the diagnosis of suspected primary biliary cirrhosis.

1.2. Radioisotope scanning

A variety of focused collimators is now in general use for the delinea- tion of radioactivity in organs or in sections of the human body. De- pending on the size of the volume containing the radioisotope to be detected, its location within the body, and the energy of the gamma rays emitted, a particular kind of collimator in combination with a sodium iodide crystal of a certain diameter may yield optimum results. A method for the evaluation of focused collimator performance, which was developed at the Agency's laboratory l8, was applied to 12 commercially manufactured collimators from USA (Picker) and 5 collimators from Italy (SELO). The characteristics of each collimator were determined with gamma rays of one or two energies. The geometrical characteristics of a long-focus collimator (SELO FC3L) are shown at the top of Fig. 14. This 37-hole collimator has a geometrical focal distance of F = 15 cm and for the 131I gamma rays in air its resolution (FWHM) is better than 2 cm for courses at distances between about 6 and 21 cm. It achieves its best resolution of 1.3 cm at a distance of 13 cm, while its resolution is better than 1. 5 cm at distances between 10 and 18 cm. As the resolution of this collimator is superior to the 19-hole collimator generally used for organ scanning (Fig. 15 in report of footnote 18), its plane-source sensitivity is reduced by nearly a factor of two. Pre- viously this was regarded as a serious disadvantage of long-focus collimators. However, the rapidly increasing use of compounds with a short effective half-life, which allow the administration of large amounts of radioactivity, very much over-compensates for this loss of sensitivity. The response of the long-focus collimator to line sources in an absorbing medium is shown at the centre of Fig. 14. An air gap of 2. 5 cm was maintained between the face of the collimator and the absorbing medium of unit density. The resolution of the collimator, which depends mainly on its geometrical characteristics, is shown to be little affected by the gamma ray attenuation, while the count rate at increasing source distances.is markedly reduced by attenuation. A collimator of this type appears well suited for scanning of medium size organs which do not extend to great depth, such as kidneys or the spleen. The resolution and depth-sensitivity of the collimator will not vary much over the thickness of these organs. However, large organs, such as the liver, lungs and brain, exhibit a greater thickness and greater geometrical spread throughout the body. For these organs, probably no single detector- collimator combination can yield optimum results in clinical practice.

18 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No.77, IAEA, Vienna (1967) p. 62. 38 VI. MEDICINE

FIG. 14. Top: Geometrical characteristics of a long-focus collimator. Centre: Collimator response to 131I line source in an absorbing medium. Bottom: Response to two opposed collimators by summing the detector outputs.

By using pairs of opposed collimators their useful range can be greatly extended. For example, at the bottom of Fig. 14 the response to line sources in an absorbing medium is shown for two of these long- VIENNA AND SEIBERSDORF 39 focus collimators placed 30 cm apart, with an air gap of 2. 5 cm next to each collimator. When the pulses from the two detectors are summed, this geometry results in a rather uniform response to the 131I gamma rays at all depths. If in additions to the sum, the counts from the detector closest to the organ of interest are recorded separately, either one of the two read-outs should be optimum depending on the spread of the radioactivity with depth.

FIG. 15. IAEA liver-slice phantom, consisting of a plastic container to be filled with radioactivity, for intercomparison of scintigraphic reproduction.

For testing the overall performance of scanners (collimator plus read-out systems) a "liver-slice" phantom has been constructed (Fig. 15). It consists of a plastic container which can be filled with radioactive material. Within its volume, 8 voids are distributed with sizes ranging from 0.8 to 4.0 cm in diameter. Their height is equal to the inside dimension of the container, which is only 1 cm. Within the scanning plane, however, the phantom represents a large source (13X 20 cm). Its inside edges with straight and curved sections serve for testing the • uniformity of the scintigraphic reproduction, which is a particularly critical problem for scintillation cameras. The diameter of the smallest void that can still be recognized on a scintigraph is a measure of the resolution of the system within the plane of the phantom. By scanning the liver-slice phantom with the long-focus collimator shown in Fig. 14, the voids with either a 1.6 or 2.0 cm diameter are the smallest that can still be clearly identified. As the resolution of this collimator varies between 2.2, 1.3 and 1.9 cm at 5, 13 and 20 cm distance, respectively, from the face of the collimator, the results obtained with the phantom are in agreement with the previously established collimator resolution. When the phantom was placed in an absorbing medium, the scans shown in Fig. 16 were obtained. Using a single collimator, the count-rate decreases with increasing distance from the collimator while with the two opposed collimators, the count-rate is rather independent of the position of the phantom. Furthermore, the observed resolution is the same for the single collimator and the pair of collimators, and it does not vary much with the position of the phantom relative to one of the collimators. All these findings verify the collimator characteristics established by means of line-source measurements (Fig. 15). Therefore the liver-slice phantom 40 VI. MEDICINE LIVER-5LICE PHANTOM IN UNIT- DEN5HX MEDIUM Air gap: 2.5cm

I crystal 2 crystals Separation distance: 30cm

5 cm

7.5 cm

10 cm

am . 12.5 cm

Distances measured from upper crystal

FIG. 16. Scans of liver slice phantom in an absorbing medium using either a single or a pair of opposed long-focus collimators. VIENNA AND SEIBERSDORF 41

appears to be well suited for the investigation of scintigraphic instrumentation under a variety of experimental conditions. Fifteen such liver-slice phantoms were constructed at the workshop. A method was worked out for the uniform labelling of anion exchanger (Dowex-1) with 203Hg in the form of a negatively charged chloride complex ion. This radioactive material was used for filling each phantom with an activity of about 100 /uCi. Twelve of the phantoms were mailed to manufacturers of scintigraphic instruments in several countries (France, Japan; The Netherlands, UK, USA) for an intercomparison of different types of instruments. Though some preliminary results have been obtained, some difficulties arose because of the relative short half-life (47 days) of 203Hg. The interest in such an intercomparison is very great and attempts are being made to seal the liver-slice phantoms in such a way that they can be filled with a radioactive solution by the user.

1.3. Whole-body counting

Work has been completed on a broad evaluation and comparison of whole-body counting techniques using Nal(Tl) crystals for the assay of gamma ray and beta ray emitters in persons. The objectives of the programme were (1) to provide technical advice to 3 laboratories investigating under Agency research contracts the metabolism and toxicity of 90Sr and 226Ra in people, (2) to acquire systematic information which would permit of the design of suitable whole-body counters for contamination monitoring and clinical studies in any additional Member States requesting Agency assistance, and (3) to determine the best methods to use in the Agency's own programme of contamination monitoring, Thorotrast measurements, and studies of clinical isotope procedures. The investigation has en- compassed the following conditions: 3 basic detector-body geometries during measurement (subject in arc, in chair, or reclining beneath moving crystal), Nal(Tl) detectors of 4 sizes (20 cm diam. X 10 cm to 2.5 cm diam. X 2. 5 cm), human bodies of many sizes, phantoms of several designs, radioisotopes emitting gamma or beta rays, gamma ray energies ranging from 0. 03 to 2. 75 MeV, and radionuclides that concentrate in various regions of the body.- Details of the work are being published in 3 papers. The following general conclusions have been reached: (a) For most purposes the measurement geometry of choice consists of a single fixed crystal beneath which the subject is moved from head to foot while reclining (first prone, then supine) on a bed. (A similar procedure, using one fixed crystal above and one fixed crystal below the bed, may be significantly more convenient for certain subjects. ) This technique is distinguished by good sensitivity and accuracy, and by the requirement only for an inexpensive radiation shield concentrated near the detector; (b) When assay of activity in the subject is based on counts recorded in the gamma ray photopeaks of the pulse-height spectrum, this procedure is usually capable of an accuracy of about 3% (standard deviation) if appropriate calibration is performed and a statistically adequate number of counts is collected; (c) When the radionuclide in the subject is known, greatest accuracy of assay can usually be achieved by summing all the counts in the full gamma ray spectrum rather than only in the photopeak Using elementary calibration procedures, almost any gamma ray emitting nuclide distributed in almost any pattern in a body of almost any size can 42 VI. MEDICINE be assayed with an error not exceeding a few percent. This technique is especially useful in clinical applications of whole-body counting. It has the added virtue that it can be set up without expensive pulse height analysis equipment; (d) By calculations and simple normalizing measurements it is possible accurately to extrapolate gamma ray calibration data for one whole-body counter (counts per minute recorded per microcurie in body) to others having quite different measurement geometries, crystal sizes, and spectral energy bands; (e) 90Sr and its daughter 90 Y, both pure beta emitters, can be reliable and accurately assayed when present in the skeleton at burdens well below the maximum permissible (2 juCi) by means of the bremsstrahlung they produce; (f) All of the above conclusions apply almost identically to Nal(Tl) detectors of any common size and shape. For practical purposes size affects only the sensitivity of the system. Whole-body counters designed with these principles as guides will give excellent performance at a fraction of the cost that is often considered necessary.

1.4. Profile scanning One attractive feature of the whole-body counting procedure just described (in which the crystal reads from head to foot of the reclining subject) is that information can be obtained on the location of the activity along the length of the body. This information, supplementary to data on the activity in the entire body, is very useful in certain studies. For example, with Thorotrast cases it is important to distinguish between activity systemically deposited in the liver-spleen region and that peri- vascularly deposited at the site of injection; in contamination monitoring it is necessary to distinguish between systemic distributions and lung burdens; in clinical investigations it is helpful io observe relative concentrations in various organs. Progress in refining this technique has been made in previous years. Recently, new mathematical methods have been tested for converting the count rate profile along the length of the body to an activity profile. This conversion is necessary since only the activity profile is of biological interest, yet it is not simply proportional to the count rate profile because many gamma rays are counted far from their points of origin in the body. The mathematical objective is to make this conversion as accurate as possible, achieving physically reasonable results with error estimates attached. For the solution of this type of' problem there are many different mathematical procedures available. However, it is by no means clear which of them may be expected to yield the most meaningful results, nor what the detailed effects are of changing the values of experimental parameters such as source strength and distribution, detector collimation and background counting rate. To explore the latter problem experi- mentally would be extremely time consuming. However, the need for this has been recently circumvented by calculative procedures which allow the simulation of many experiments, including the effects of random counting rate errors, entirely by computer.

1.5. Thoron assay system Equipment has been assembled and put into operation for the sensitive and selective measurement of thoron ( 220Rn) in the Thorotrast investigations. VIENNA AND SEIBERSDORF 43

19 It is similar to that developed for related work elsewhere , and can be used for assay of its parent 224Ra in a solution or of thoron in the breath of a patient. In the former case the thoron is continuously de-emanated from the solution by a stream of air bubbling through it. This air, or the patient1 s exhaled breath, is led into an empty metal can of sufficient volume that the average residence time of the air (and thoron) in the can is several times as great as the thoron half life (54 sec). Hence most of the thoron decays in the can, giving rise to positively charged Po and 212Pb daughter products. These are collected electronically during a period of minutes to hours onto a planchet having a potential of -3000 V to - 4000 V and located at one end of the can. Subsequently the accumulated 212Pb is assayed by alpha-counting of its radioactive descendants (212Bi, 212Po) with a ZnS scintillation detector. Sensitivity is adequate to assay sub-picocurie quantities of 224Ra in solution, and nanocurie activities of Thorotrast in living persons. The method discriminates against any other possibly interfering radionuclide (e.g. 222Rn) by many orders of magnitude.

1.6. Computer programme for curve-fitting

The problem of fitting a theoretical curve to a series of experimental data points is one common to nuclear medicine and to many other branches of science. Perhaps the most frequently quoted example is that of fitting a series of exponentials to decay curves containing several components, or to metabolic data representing the passage of a radioactive tracer through a number of exchangeable body compartments. Throughout the world, many computer programmes have been written for tackling these problems. These programmes mostly use non-linear least-squares minimization routines that call for the partial derivatives of the analytical function to be fitted. In cases where this method is applicable, it is probably the most efficient procedure available, though it often fails to converge when the parameters are highly correlated. Other, considerably more sophisticated, programmes have been developed that overcome this difficulty, but none was known to be available that could be conveniently adapted to the IBM-7040 computer used by the Agency. To fill the gap between the unduly simple and unduly complicated programmes referred to, an iterative curve-fitting programme was developed that always converges to a "best fit" in a finite number of steps from a predetermined starting point provided by the user. The programme is extremely simple to use in that only two statements need be changed if a different analytical function is required. Also, the programme offers the user a number of different weighting factor options by which he can exercise control over the regions of his data that he wishes to be fitted with the greatest precision. With only a small increase in complexity, the user can place restraints on the values of the parameters (e.g. confine them within a specified numerical range) or he can simultaneously fit a series of different sets of data that have one or more parameters in common. The programme has been successfully applied in fitting empirical equations, with up to 5 independent parameters, to data representing the absorbed

15 DUDLEY, R.A., KUCHTA, D. R., TAVLA, M., DAY, J.F., III., "Measurement techniques , for Tn, Rn, and Po", Annual Progress Report, Radioactivity Center, MIT Rep.(May 1957) p.49. TABLE VII. COMPARISON OF SERUM ALBUMIN MEASUREMENTS ON SAMPLES FROM THREE BATCHES OF POOLED SERUM3

SERUM A ' SERUM B SERUM C INSTITUTE METHODS Replicates Mean Replicates Mean Replicates Mean

Paper electrophoresis, A 4.64 - 4. 23 - 0.93 - Kjeldahl

B - 4. 72 - 3. 77 - 1.26 Paper electrophoresis, biuret

C 4. 93-4. 96 (4) 4. 94 3. 77-3. 88 (4) 3. 83 1. 33-1. 43 (4) 1. 37 Biuret

E 4.81, 4.90 4. 85 3. 56, 3. 88 3. 72 1.30, 1.42 1. 36 Isotope dilution, biuret 4. 14-4. 62 (12) 4. 34 3.39-3. 78 (12) 3. 60 1.10-1.29 (12) 1. 19 Paper electrophoresis, biuret F w O G - 5. 0 - 4.2 - 1.6 Biuret

H - 4. 10 - 3. 46 - 1.21 Paper electrophoresis, biuret Z M - 4. 04 - 3. 39 - 1.18 Immunochemical 1 Paper electrophoresis, - 5. 22 - 4. 22 - 1.45 Kjeldahl

4. 4, 4. 4 4. 4 3.3, 3.2 3.2 1.2, 1.2 1.2 Biuret J

- 5. 0 - 4.5 - 1. 5 Paper electrophoresis

K 4. 70, 4. 70 4. 70 3. 58, 3. 86 3. 72 1.35, 1.40 1. 37 Biuret

GRAND 4. 66 3. 82 1. 30 MEAN a All values are of serum albumin conceration (g/lOOml) VIENNA AND SEIBERSDORF 45 dose build-up at different distances, from a point source of photons in water. It has also been used for fitting an empirical equation to experimental collimator response functions obtained in the profile scanning studies (see 1.4. of this part).

2. SUPPORT OF OTHER AGENCY ACTIVITIES

2. 1. Radionuclide monitoring

The whole-body counter has been used for monitoring radionuclide contamination in Agency personnel possibly exposed in the course of their professional activities. Such individuals include, in particular, staff members of the Agency's laboratory and Safeguards Inspectors. During the year 24 investigations were performed on 15 persons. The analytical equipment set up for the medical activation analysis programme has been used for several isolated measurement problems originating elsewhere in the laboratory, which required high resolution gamma ray spectroscopy.

2.2. Labelled proteins for the study of protein metabolism in malnutrition

In support of the Agency1 s Co-ordinated Research Programme on the Use of Radioisotopes in the Study of Malnutrition in Tropical and Subtropical Regions, a further two batches of 125I-albumin and three of 125I-gamma-globulin have been prepared and samples of these distributed to groups participating in the Programme, to be used by them as reference materials against which to compare their own locally prepared 131I-labelled proteins in metabolic studies carried out using double tracer techniques. As regards labelled albumin preparations, such intercomparison studies have shown reasonable agreement between the metabolic behaviour of the Agency preparations and those prepared locally by the participating groups. A similar measure of agreement has not been achieved with labelled gamma-globulin preparations. It remains to be established to what extent the observed discrepancies are due to differences in the gamma- globulin fractions used for labelling, to differences in labelling technique and to deterioration of labelled preparations during storage and transport. Also in support of this Co-ordinated Research Programme, an intercomparison of serum protein measurements was carried out; in this, samples from three batches of pooled serum were distributed to groups participating in the Programme, with the request that they measure total protein, albumin, total globulin and gamma-globulin concentration on each sample using the methods in routine use in their own laboratories. Table VII, which shows the results of the albumin concentration measurements in this intercomparison, illustrates the degree of uncertainty in such results.

2.3. Applications of whole-body counting

Training in whole-body counting techniques was provided for one doctor from a developing country. He was interested in the use of simple instruments for the study of the metabolism of 131I-labelled proteins as 46 VI. MEDICINE part of the above mentioned Co-ordinated Research Programme. The performance and use of whole-body counters were also demonstrated to 14 students participating in bioassay course organized by the Seibersdorf Laboratory. Support was continued for three laboratories in Member States investigating 90Sr and radium metabolism in luminous-dial painters. The analysis of the interlaboratory comparison of relevant measurement procedures was completed, and a joint paper on this work was submitted for publication. Facilities and advice were made available to a Vienna hospital for certain clinical studies with the whole-body counter. In particular, investigations were supported on the retention and localization of 64Cu in 6 patients with Wilson's disease. The whole-body counter and technical support were made available to health physicists from the Gsterreichische Studiengesellschaft fur Atomenergie (Seibersdorf) for monitoring radioactive contamination in persons occupationally exposed at the reactor centre. 98 measurements were made on approximately 25 persons. Traces of 131I, 203Hg, or 103Ru were detected in a few persons, and some information on the time-course of 103RU retention was obtained.

2.4. Study of toxicity of Thorotrast in Vienna cases

The catalogue of case data for epidemiological purposes has been extended and, in collaboration with doctors at the II. Frauenklinik, observations on chromosome aberration frequencies in peripheral blood leukocytes have been continued. Statistical evaluations of the results have not been completed. A paper on certain aspects of Thorotrast dosimetry has been submitted for publication. VII. NUCLEAR TECHNIQUES IN AGRICULTURE

1. SOIL FERTILITY, IRRIGATION AND CROP NUTRITION

As in previous years, all labelled nitrogen and phosphate materials for the co-ordinated rice, maize and wheat programmes were weighed out for each experimental plot and sent to the contractors. For the co- ordinated tree programme, special glass ampoules were filled with labelled 32P and 86 Rb solutions and despatched to the contractors together with ampoule crushing devices custom-built at the laboratory. Two plastic greenhouses were installed for pot and small scale field experimentation, and for plant breeding and selection purposes. A cold room was installed in the basement of the laboratory for carrying out experiments at temperatures from 2 to 15°C.

1. 1. Co-ordinated rice project

1. 1. 1. Field experiment 1966/67 (nitrogen sources)

The experiment compared shallow placement and surface top dressing 15 of N labelled (NH4)2S(\, urea, NELjNOs and NaN03. Labelled superphosphate was applied on the surface at the time of transplanting the rice. The analyses of all experiments were completed. The results show that (NH4)2SO4 and urea are generally equally efficient. Nitrate sources are much less efficient than (NH^SOi and urea, particularly when applied at transplating time. The utilization of phosphorus is not affected by the nature and timing of application of the nitrogen source.

1. 1. 2. Field experiment 1967/68 (mixed N-P sources)

The experiment involved 13 sites (UAR, Hungary, Italy, India (2X), Pakistan, Burma, Korea, Thailand, The Philippines, Ceylon and Taiwan (2X)), and was similar in organization to 1. 1.1 but compared 32P and 15N labelled (NH4)2HP04, a nitrophosphate of low and a nitrophosphate of high phosphorus solubility, with (NH4)2S04 and super phosphate as standard treatments (Table VIII). Table IX lists the %P in the rice plants that was derived from the fertilizer at the stage of primordial initiation. From this table it may be seen that ammonium phosphate applied at a depth of 5 cm at the time of transplantation was slightly more efficient as far as phosphate uptake was concerned than superphosphate and nitrophosphate (treatments A, C, and D). Nitrophosphate of 75 and 25% water soluble phosphorus content applied at the time of transplantation resulted in approximately the same phosphate utilization by the crop. A final report on this experiment will be published in the 1968 annual report.

1. 1. 3. Field experiments 1966/68 (depth of nitrogen placement)

A field experiment, comparing various methods of nitrogen placement was carried out in Ceylon, Madagascar, The Philippines, Taiwan and

47 48 VII. AGRICULTURE

TABLE VIII. EXPERIMENTAL TREATMENTS OF THE CO- ORDINATED RICE PROGRAMME 1967/68. (mixed nitrogen - phosphorus sources)

Treatment Placement and timing

Nitrogen fertilizer Phosphorus fertilizer

A Ammonium sulphate applied at Superphosphate applied at trans- transplanting in rows at 5 cm planting, broadcast on the surface depth

B Ammonium phosphate (B) applied Phosphate applied combined with at transplanting in rows at 5 cm nitrogen depth

C Nitric phosphate (75°jo soluble Phosphate applied combined with P) applied at transplanting in nitrogen rows at 5 cm depth

D Nitric phosphate (25% soluble Phosphate applied combined with P) applied at transplanting in nitrogen rows at 5 cm depth

E Ammonium sulphate applied 2 Superphosphate applied 2 weeks weeks before primordial initia- before primordial initiation, tion, broadcast on the surface broadcast on the surface

F Ammonium phosphate (B) applied Phosphate applied combined with 2 weeks before primordial ini- nitrogen tiation, broadcast on the surface

G Nitric phosphate (75soluble Phosphate applied combined with P) applied 2 weeks before pri- nitrogen moridal initiation, broadcast on the surface

H Nitric phosphate (25°Jo soluble Phosphate applied combined with P) applied 2 weeks before pri- nitrogen mordial initiation, broadcast on the surface

Thailand. The experiment comprised surface broadcast application (A), placement in rows on the surface (B), placement in rows 5 cm deep (C), in rows 10 cm deep (D), and in rows 15 cm deep (E) of N-15 labelled ammonium sulphate.

From Table X which lists the results of 4 of the 5 countries it may be seen that shallow placement of at least 5-10 cm results in a considerable gain in uptake of fertilizer nitrogen. This is presumably due to a decrease in gaseous nitrogen losses when (NH4)2S04 is placed under reduced conditions, and consequently no oxidation to nitrate and subsequent reduction to nitrite and gaseous nitrogen products can take place. TABLE IX. CO-ORDINATED RICE PROGRAMME 1967/68 (Mixed N-P sources)3

Treatments

Applied at transplanting Applied 2 weeks before primordial initiation ~ Countries A B C D E F G H < (NH4)2SO4 + Am. Ph. B. Nitr. Ph. Nitr. Ph. (NH4)2S04 + Am.Ph.B. Nitr. Ph. Nitr. Ph. w superphosphate 75F?O 2fPl° superphosphate 75<7O 2ff]o Z Z> Burma 7. 0 8.5 7.6 6.4 11.2 12.3 11.7 8.1 > Ceylon 37. 4 44.8 36.2 35.1 25.4 28.7 18.6 17.4 z o Hungary 27. 4 43.4 36. 5 42. 1 32.1 25.1 9.5 10. 9 cr> M Italy 2.8 5.1 3.9 2.9 3.1 4.2 1.7 1.6 3 W Korea 10.0 14.7 13.7 10.8 14.1 15.7 16.5 14.5 5*> t/> Philippines 9.2 16.1 12.6 8.8 13.9 14.8 13.4 8.3 o !a Taiwan-I 20.0 21.8 20.0 20.2 18.0 19.3 18.8 14.3 T! Taiwan-II 12. 4 13.5 12. 5 12.8 15.5 17.2 15.9 12.2

Thailand 70. 0 51.3 54.5 47. 9 50.2 58.1 55.9 50. 8

UAR 21.4 20.5 17.0 15.5 22.0 25.0 11. 6 9. 7

a Shown as percentage phosphorus in the Plants derived from fertilizer at primordial initiation

CD 50 VII. AGRICULTURE

TABLE X. FIELD EXPERIMENTS WITH RICE 1966/68 (depth of nitrogen placement)

^^\^Treatments A B C D E

Cou ntr P7ON uptake from fertilizer)

Ceylon3 54.7 49.0 54.5 65.0 67.9

Philippines 7.1 8.3 18.5 19.3 21.6

Taiwan 20.4 19.3 25.2 26.8 31.2

Thailand 11.8 11.2 32.4 37.0 38.1

a figures refer to 40 days leaf sampling

A = surface broadcast: B = surface in rows: C = 5 cm depth in rows: D = 10 cm depth in rows: E = 15 cm depth in rows

1. 2. Co-ordinated maize project

1.2. 1. Field experiments 1966/67 (time and rate of nitrogen application)

The experiment was designed to determine the best method of side dressing of (NH^SC^. 100 kg (^NH^SO^ 1% 15N atom excess was applied in two or three equal doses in a band as shown in Table XI. At planting time the band was at 5 cm distance from the plant row, the top dressings were made 50 cm from each row. In one treatment, phosphorus and nitrogen fertilizers were placed in separated bands, to evaluate a possible mixing effect of fertilizers on the utilization of nitrogen and phosphorus by the crop. In all countries, top dressing of nitrogen was more efficient than placement at seeding time. In five of the 8 countries, top dressing as late as tasseling was more efficient than top dressing at a height of 50 cm (see Table XII). The mixing of nitrogen and phosphorus fertilizers had a pronounced effect on phosphorus uptake from superphosphate. Table XIII shows that in 7 of the 8 experiments the uptake of phosphorus from superphosphate was higher when it was mixed with ammonium sulphate.

1. 2. 2. Field experiments 1967/68 (time and method of application of various nitrogen sources)

16 (NH4)2S04, urea and NH4NO^ labelled with 0. 5% excess N were applied at a total rate of 160 kg(N)/ha, in two doses of 80 kg/ha. The fertilizers were applied in a band at seeding time and when the plants reached a height of 50 cm as a top dressing. The nitrogen fertilizers were mixed with labelled superphosphate in one band. The effect of the nature and placement method of nitrogen on the utilization of phosphorus from superphosphate has been illustrated in Table XIV. Only in one country (Peru) was the utilization of phosphorus from superphosphate much less when mixed with NH4NO3 than with

(NH4)2S04. This is presumably due to the high alkalinity of the Peruvian TABLE XI. EXPERIMENTAL TREATMENTS OF CO-ORDINATED MAIZE PROGRAMME 1966/67 (method, time and rate of application of nitrogen and phosphorus fertilizer)

N as (NH4)jS04 P as superphosphate (0-20-0)

Treatment Application banded at planting

banded side dressed side dressed at planting at 50 cm height at tasseling < m A 50 kg/ha 50 kg/ha None Z 15 kg/ha N + P mixed, placed on one side of row Z labelled unlabelled unlabelled > > B 50 kg/ha 50 kg/ha None 15 kg/ha N + P mixed, placed on one side of row Z D unlabelled labelled unlabelled cn w C 33 kg/ha 33 kg/ha 33 kg/ha 15 kg/ha N + P mixed, placed on one side of row 5 CD labelled unlabelled unlabelled labelled ?0 c/> O D 33 kg/ha 33 kg/ha 33 kg/ha 15 kg/ha N + P not mixed, N on one side of row O labelled unlabelled unlabelled labelled P on the other •n

E 33 kg/ha 33 kg/ha 33 kg/ha 15 kg/ha N + P mixed, placed on one side of row unlabelled labelled unlabelled unlabelled

F 33 kg/ha 33 kg/ha 33 kg/ha 15 kg/ha N + P mixed, placed on one side of row unlabelled unlabelled labelled unlabelled TABLE XII. CO-ORDINATED MAIZE EXPERIMENT 1966 (final grain, %N derived from fertilizer)

Countries Treatments

Aa B Cb DC E F 50 50 50 50 33 33 33 33 33 33 33 33 33 33 33 33

Argentina 10.7 12.1 5.8 7.4 10.4 5. 9

Brazil 17.2 24.7 8.8 9.2 4. 2 19.8 > Colombia 18.1 35.7 6.8 6.9 21.4 28.2 2O o Ghana 13.2 22.4 8.0 8.8 17.0 8.9 c 1 Mexico 18.7 16.3 12.1 16.8 33. 0 t- - -J c Peru 10. 7 29.8 7.7 6.5 17.6 30.8 * M Romania 18.8 32.7 11.2 13.0 17.5 19. 5

UAR 9.3 14.8 6.5 5.2 8.8 6.0

a 1S 50 - 50 = 50 kg N labelled (NH4^S04 at seeding, 50 kg non-labelled (NH4)2S04 at 50 cm height. b 33 - 33 - 33 = 33 kg N15 labelled (NH^SQ, at seeding, the other applications, non-labelled at 50 cm height and tasseling. c N and P not mixed. VIENNA AND SEIBERSDORF 53

TABLE XIII. CO-ORDINATED MAIZE EXPERIMENT 1966 (2nd sampling, 50 cm height, %P in the plant derived from fertilizer)

Countries Treatments mixed non-mixed

Argentina 38.2 10.9

Brazil 45. 3 30.6

Colombia 29.8 18.3

Ghana 38.2 40.1

Mexico 7.7 2.1

Peru 33. 1 11.7

Romania 21. 1 14.8

UAR 2. 2 0. 9 soil, where it is known that nitrate fertilizer may have unfavourable effect on crop development. As shown in Table XV in 4 of the 6 countries, the mixing of nitrogen and phosphorus fertilizer resulted in a higher uptake of phosphorus from superphosphate. Only in the case of Argentina did local treatment (hill drop of urea and superphosphate) result in a higher uptake of phosphorus from superphosphate. The utilization of nitrogen from the three fertilizer applications at 50 cm plant height showed a superiority of (NH4)2S04 in the case of Peru, and UAR, i.e. where the soils are alkaline. Mixing of nitrogen and phosphorus fertilizers did not significantly affect the utilization of nitrogen by the maize plants. A final interpretation of the data will be made when the analyses of the grain data have been completed.

1. 2. 3. Amounts of 15N required in field experiments with maize Based on the. results of 4 years field experimentation an evaluation was made of the minimum amount of 15N required per hectare for field experimentation. The results are illustrated by Fig. 17. If for example 80 kg (N)/ha are to be applied at a site where the total nitrogen uptake (tops and roots) is likely to be of the order of 100 kg/ha and the expected utilization of nitrogen fertilizer 70%, then a total amount of 0.33 kg(15N)/ha is required. The corresponding enrichment for an application of 80 kg (N)/ha could-be as low as 0.41% 15N atom excess. If the coefficient of variation is expected to be greater than 10%, the requirement for enrichment decreases proportionally and in the above case would become 0. 21% 15N atom excess for a variation coefficient of 20%.

1. 3. Co-ordinated wheat project

1.3. 1. Preliminary field experiments 1967/68 (time of application of

(NH4)2S04) In two countries (Peru and Romania) an experiment was carried out, studying the time and rate of application of (NHJ2SO4 (0. 9% 15N excess). cn

TABLE XIV. CO-ORDINATED MAIZE PROGRAMME 1967/68 (Effect of nature of nitrogen sources on the %P derived from superphosphate, when the plants had a height of 50 cm)

Treatments Argentina Colombia Ghana Mexico Peru UAR

ammonium sulphate mixed with

superphosphate 36.0 21.9 78.5 38.2 40.6 18.3

urea mixed with superphosphate 23.4 16.0 59.2 24.8 9.9 12.4 > Ammonium nitrate mixed with 2O • superphosphate 31.8 22.6 75.1 31.5 20.8 17.1 o c - ammonium nitrate not mixed t- H with superphosphate - - 64.3 - - 7.2 a urea not mixed with tn

superphosphate 28.0 8.5 - 20.4 13.0 -

local treatment 32. 8 a 18.6b 77. 8C 24. 6 c 7.2b 18. 3 c

a Hill drop of urea instead of band placement b Urea side dress instead of banding at planting time c Broadcast instead of band application of ammonium nitrate TABLE XV. CO-ORDINATED MAIZE PROGRAMME 1967/68 (Effect of nature of nitrogen sources on the %N derived from the nitrogen fertilizer when the plants had a height of 50 cm)

Treatments Argentina Colombia Ghana Mexico Peru UAR

ammonium sulphate mixed with

superphosphate 43.4 35.1 40.1 54.2 32.6 57.9

urea mixed with

superphosphate 38.4 43.2 54.6 53.3 26. 7 45.7

ammonium nitrate mixed with

superphosphate 47.2 45.3 34.6 52. 5 20. 0 51.6

ammonium nitrate not mixed

with superphosphate - - 26.3 - - 57.4

urea not mixed with

. superphosphate 38. 6 34. 1 - 48.4 29.6 -

a . b' C c C local treatment 46. 5 4.2 45. 6 18. 7 b 27.2 a Hill drop of urea instead of band placement Urea side dress instead of banding at planting time c Broadcast instead of band application of ammonium nitrate 56 VII. AGRICULTURE

Total kg (N) / ha taken up by crop (tops + roots)

FIG. 17. The amount of nitrogen-15 required for field experiments as a function of the predicted total nitrogen uptake by the crop and the percentage utilization of the fertilizer applied (assuming a standard deviation of 10%).

The total application of 90 kg(N)/ha was divided into two or three equal doses of which only one dose was labelled with 15N. The fertilizer was applied at the seeding, tillering and boot stages. Preliminary analyses indicated that the chosen plot size and layout was satisfactory for future work. No lateral movement of fertilizer nitrogen from fertilizer rows to non-fertilized rows could be detected.

1.4. Co-ordinated research programme on tree crop fertilization

This programme was initiated in 1966 to study the distribution of active roots in different tree crops of economic value specially to developing countries, as a preliminary step in the study of the various factors affecting efficiency of fertilizer utilization. In 1967 contracts were made for research on citrus (Spain and Taiwan), cocoa (Ghana), coconut (Ceylon), coffee (Colombia) and oil palm (Ivory Coast). The contracts made in the preceding year for research on coconuts (Philippines), coffee (Kenya) and olives (Tunisia) were continued. Most of the work done was directed towards familiarizing the contractors with the experimental techniques, a study of variability between trees in tracer uptake, and establishment of leaf sampling methods. The experimental technique consists of injecting 32P solution into the soil around the trees at different distances and depths. The specific VIENNA AND SEIBERSDORF 57 activity of phosphorus in leaves of the same physiological age is used as a measure of 32P uptake by the tree to assess treatment differences in root activity. The design for the first series of standard treatments consists of a 4 (depth) X 4 (distances) factorial experiment with 3 replications. Since generally, agricultural laboratories do not have the facilities for the bulk handling of quite large amounts of radioactivity, the 32 P materials for the experiments were prepared and supplied through the IAEA laboratory, which also provided advice and analysed leaf samples for contractors who did not have the facilities to do their own analyses. Localized soil heterogeneity with respect to phosphate can jeopardize the results of experiments in root activity using 32P owing to greater dilution of the 32P with soil phosphate at spots of higher soil phosphorus content. This can be a serious problem, particularly where the experimental site has been previously treated with phosphate fertilizers. A greenhouse experiment carried out at the laboratory on barley plants grown on very phosphorus-deficient soil pretreated with different levels of soil phosphorus showed a significant interaction between levels of carrier used with the 32P and the levels of soil phosphorus on the uptake of 32P by the plants (Table XVI). High carrier level masked the effects of the different levels of soil phosphorus, but resulted in reduced uptake of 32P. The highest uptake of 32 P is ensured at low carrier level and is higher when the carrier is applied some time before 32P injection.

TABLE XVI. GREENHOUSE EXPERIMENT ON 32P UPTAKE AS A FUNCTION OF 31P CARRIER LEVEL AND SOIL PRE-TREATMENT (per 2 kg soil) Data expressed in 103 counts/min per milligram of phosphorus in the dry matter

32P and carrier Soil pre-treatment

level 50 mg P 100 mg P 150 mg P

8 (iCi 32P + 0. 04 mg P 11.2 13.8 11.7

8 jiCi 3!P + 50 mg P 18.3 13. 5 10.4

8 (iCi 32P + 200 mg P 9.1 8.6 7.3

1.4. 1. Experiment on orange trees, Spain (IAEA Research Contract No. 541)

The first 4X4 factorial experiment to study root activity was done on 20-year-old orange trees (variety Navel Grotted on Amargo) planted on a calcareous sandy loam soil type in Valencia during the wet season (July 1967). At the 25 and 35 daysampling, the position at 3 metre distance and 30 cm depth showed the highest root activity. Since the trees were planted 7 metres apart, it is probable that the root activity at 3 metres distance has been underestimated — owing to competition for the 32P by adjacent guard trees. (See Table XVII) 58 VII. AGRICULTURE

TABLE XVII. ROOT DISTRIBUTION STUDY ON ORANGE TREES (SPAIN) Data expressed in counts/min per milligram of phophorus in leaf samples

Depth of application Time of sampling Distance from base of stem (metres)

(cm) (days) 0. 5 1.0 2.0 3.0

15 29 8 118 97

0 25 39 13 98 109

35 74 63 174 121

15 61 21 215 119

30 25 43 53 187 335

35 74 129 405 1039

15 23 0 22 30

60 25 13 0 114 42

35 18 5 118 97

15 21 9 0 5

90 25 19 16 0 18

35 16 42 87 71

1.4. 2. Experiments on coconut trees

(a) Ceylon (IAEA Research Contract No. 515)

A preliminary experiment to study the relative uptake of 32 P and 86Rb by mature coconut trees showed that 86Rb is taken up in considerably larger amounts than 32P both initially and later on (10 to 40 days after application of radioisotopes to the soil), in contrast to the experience with coffee trees (see 1.4.4.). For 32P, analysis of leaflet samples from the 6th fully opened frond were considered to be the most suitable since they contained more activity than those from much younger or older fronds. In the case of rubidium, there was no significant difference in activity between fronds 1 to 9, in older fronds the rubidium activity decreases (Table XVIII).

(b) Philippines (IAEA Research Contract No. 293)

The first 4X4 factorial experiment was done on 10-year-old coconut palms planted 8 metres apart on a well-drained sandy loam soil in Guinobatan, Albay, during the rainy season in August 1966. A second experiment was done during the dry season in April 1967. VIENNA AND SEIBERSDORF 59

TABLE XVIII. ROOT DISTRIBUTION OF COCONUT TRESS (CEYLON) Assessment of sampling technique from comparisons of the activities in different leaves of 4 different palms sampled 20 days after application

leaf 32P activity® 86 Rb activity3

number palm numbers palm numbers 1 2 3 4 1 2 3 4

1 62 84 222 20 150 780 494 291

3 258 127 415 98 102 686 628 375

6 240 178 320 98 118 603 575 353

9 253 159 233 88 81 533 575 306

12 184 125 218 33 71 465 436 224

15 241 112 138 0 50 358 209 203

18 190 116 170 0 58 318 32 168

a in counts/min per 10 grams of dry matter The results of the first (wet season) experiment show that under the particular set of environmental conditions root activity of 10-year-old coconut palms was highest at a distance of 1 metre from the tree and at a depth of 15 cm. However, the differences in root activity at the various positions tested were not very marked, possibly due to a low activity of the 32P solution at the time of injection. The second experiment was carried out using higher activities of 32P in the injection liquid, enabling detection of 32P to be made from leaf samples up to 60 days after injection. Leaf samples were taken at intervals of 10, 20, 30, 40, 50 and 60 days after 32P application. The high initial activity of roots close to the stem at 0 - 15 cm depth was confirmed (see Table XIX). The highest activity was found in the surface at a distance of 3 - 4 m from the stem. The activity at a distance of 4 m gradually decreased with time, presumably due to competition from neighbouring trees. In between 1 and 3 metres from the stem, the highest root activity was not found in the surface but at a depth of 30 - 45 cm. There seemed to be two main active areas, one close to the stem and one at a distance of about 3 to 4 m from the stem (i. e. in between two trees) each in the surface.

1.4.3. Oil Palm Experiment, Ivory Coast (IAEA Research Agreement No. 545)

A 4 X4 factorial experiment was carried out in wet season (November/ December 1967) on 7-year-old oil palms on a sandy soil at La Me to study root activity at distances of 1, 2, 3 and 4 metres away from the tree, and at depths of 0 - 5 cm, 20 - 25 cm, 45 - 50 cm, 145 - 150 cm. Leaves were sampled at intervals of 7, 14 and 21 days after 32P application. 60 VII. AGRICULTURE

TABLE XIX. ROOT DISTRIBUTION OF ADULT COCONUT TREES (THE PHILIPPINES) Leaf samples taken at regular intervals after 32P application Activities expressed in counts/min per 10 grams of dry matter (means of 3 replications)

Time of sampling depth of distance of application from base of stem after S2P applications application (cm) (days) 1. 0 m 2. 0 m 3.0 m 4. 0 m

15 703 189 264 301

30 222 231 188 318 20 45 235 191 208 98

60 204 226 284 101

15 512 272 164 551

30 436 206 283 434 30 45 . 260 273 233 457

60 210 245 175 133

15 1135 530 721 211

30 413 754 1791 430 50 45 474 260 515 922

60 296 302 493 430

15 918 243 762 225

30 664 987 803 249 60 45 476 808 467 912

60 293 249 803 541

Results given in Table XX indicate similar root activity at all distances tested, highest activity up to a depth of 25 cm and negligible root activity deeper down at 150 cm.

1.4.4. Experiment on coffee trees, Kenya (IAEA Research Contract No. 438)

The work during the year was confined to preliminary experiments on the study of variability between trees in tracer uptake, to establish leaf sampling techniques and to compare the relative merits of 32P and 86Rb as tracers in root activity studies. The results (see Table XXI) have indicated that (i) to minimize variability, experimental trees should not only have similar vegetative growth, but also similar fruiting capacity and uniform weed growth around them; (ii) young leaves sampled two VIENNA AND SEIBERSDORF 61

TABLE XX. ROOT DISTRIBUTION OF ADULT OIL PALMS (IVORY COAST) Leaf samples taken after 7, 14 and 21 days after 32P application Activities expressed in counts/min per 10 grams dry matter (mean of 3 replications)

Time of Depth of distance of application from base of stem sampling application (days) (cm) 1.0 m 2.0 m 3. 0 m 4. 0 m

7 0 - 5 162 213 543 302

20 - 25 200 203 371 350

45 - 50 113 97 183 136

145 - 150 23 11 22 77

14 0 - 5 455 596 389 406

20 - 25 332 629 366 561

45 - 50 156 136 263 505

145 - 150 32 26 56 29

21 0 - 5 477 482 351 258

20 - 25 446 485 376 451

45 - 50 220 145 270 251

145 - 150 0 0 7 26

weeks after application of the radioisotopes contain more 86Rb than 32P, but in contrast to the former, 32P accumulates with time, and after 6 weeks the leaves contained considerably more 32P; (iii) young leaves from lower branches contain less 32P and more 86Rb than leaves from upper branches. A comparison between the uptake of 32P and 86Rb as a function of the time clearly illustrates that the latter isotope, which is similar in soil behaviour to potassium, is rapidly taken up by the roots after injection into the soil. 86 Rb therefore, measures the actual root activity distribution. The increase in 32P activity with time illustrates the root development, including root growth that takes place around the fertilized area in the soil. For practical purposes the root activity that takes reaction to the fertilizer into consideration is of more significance. When the existing situation has to be examined 86Rb, which is initially taken up at a high rate, offers an advantage. In the future, however, 32 P will be used for root development work, because it measures actual 62 VII. AGRICULTURE

TABLE XXI. ROOT DISTRIBUTION STUDIES ON COFFEE TREES (KENYA) Assessment of sampling technique from comparisons of 32P and 86Rb activity in upper and lower leaves in four trees as a function of time of sampling

Data expressed in counts/min per gram of dry matter

Element The number sampling time after application applied and location of leaves 2 weeks 4 weeks 6 weeks

1 upper leaf 5.0 115 697

1 lower leaf 8.1 49 612

2 upper leaves 2.7 25 58

2 lower leaves 3.0 15 74 Phosphorus-32

5 mCi/tree 3 upper leaves 3.2 26 178

3 lower leaves 2.9 14 139

4 upper leaves 5.5 15 87

4 lower leaves 3.6 12 76

1 upper leaf 34 18 30

1 lower leaf 80 73 53

2 upper leaves 35 73 . 91 2 lower leaves 149 62 124 Rubidium-86

5 mCi/tree 3 upper leaves 32 31 27

3 lower leaves 51 23 22

4 upper leaves 9 18 12

4 lower leaves 4 10 14 root growth in fertilized areas. A disadvantage of the use of 86Rb for field experimentation is its high 7-activity requiring great care to avoid health hazards.

1.5. Crop nutrition and water use efficiency 1. 5. 1. Field experiment with maize The experiment was carried out jointly with the ORKI staff in Szarvas, Hungary. The water treatments consisted of two quantities (400 and 600 mm) VIENNA AND SEIBERSDORF 63 given either at 4 different physiological stages of maize development or at regular intervals of 20 days. The amounts to be given by irrigation were calculated from soil moisture determinations using the neutron moisture meter before irrigation. Superimposed on the irrigation treatments were 15 two applications of ( NH4)2S04, at planting and just before tasseling time. The analyses will be carried out in 1968.

1. 6. Co-ordinated programme on nutrient supply and movement in soil systems

1. 6. 1. Soil testing for phosphorus

Using the soil from existing field experiments, chemical extraction procedures for soil phosphorus were calibrated with availability tests (A-value) in the greenhouse. It was found that for the soils under investigation, the "Olson" method (sodium bicarbonate extract) extracts amounts of soil phosphorus which correlate well with the phosphate availability test carried out under greenhouse conditions (A-values).

1. 6. 2. Soil phosphorus availability as affected by cropping

In order to study the effect of cropping on the changes in soil phosphorus availability in rice and maize soils, the soils were cropped for different times with rye grass and barley. At the beginning of 1968, an A-value experiment will be carried out with these soils.

1. 6. 3. Nitrogen losses from rice soils

15 15 A greenhouse study was made, using ( NH4)2S04, 10% N atom excess, which was designed to find out whether surface and shallow depth placement of nitrogen fertilizer results in a difference in magnitude of gaseous losses of nitrogen and how these losses might be related to the utilization of the nitrogen from the fertilizer by the rice crop. The 15N content was determined in soil, roots and shoots, to enable a nitrogen balance study to be made for the evaluation of gaseous losses.

The reduction in gaseous losses of applied (NH4)2S04 which is obtained when the fertilizer is placed at a shallow depth (5-7 cm) in the reduced zone accounts for the increase in nitrogen utilization from the fertilizer. In greenhouse experiments no indication was obtained that differences in root development might have any effect. The observed differences in utilization of nitrogen from nitrogen fertilizer placed on the surface and at a shallow depth can be explained almost completely by differences in corresponding gaseous losses of nitrogen from the fertilizer.

1. 6.4. Nitrogen fertilizer transformations in rice soils

Microbiological oxidation and reduction in soils of NH4 to N03-> N02 and gaseous nitrogen products can be stopped when the soils are sterilized. A series of experiments was carried out on sterile and non-sterile soils. The sterilizing dose was 5 X 106 rads. It was shown that the occurrence of reduced layers in rice soils is completely eliminated when the pot experiments are carried out with sterile soils and kept under sterile 64 VII. AGRICULTURE conditions. The technique will be used to study the mechanism of nitrogen losses from fertilizers under flood conditions.

1. 7. The analysis of nitrogen-15 in biological materials

1. 7. 1. Modification of laboratory routine procedure

One of the time consuming operations in the analysis of large numbers of plant samples for their 15 N content is the digestion of plant material by the "Kjeldahl" method. A new approach was adopted in the Seibersdorf laboratory for the analysis of 15N in plant samples based on the "Dumas" method. The finely ground plant material is mixed with copper and calcium oxides in a glass tube. After evacuation of the air, the tubes are sealed and heated in a furnace at 500°C for three hours. A special inlet system was constructed for connection to the mass spectrometer. The inlet system consists of a rotating stainless steel cylinder in which 12 glass tubes can be fitted. An electro-magnetic switch operates a rod which crushes one of the glass tubes and enables the nitrogen gas to enter the spectrometer tube.

1.7.2. Analysis of 15N in small samples

Small amounts of nitrogen gas (microgram quantities) cannot be analysed in a mass spectrometer. However, using a high frequency discharge through the nitrogen gas with subsequent measurement of the intensity of 14N and 15N lines by means of an emission spectrograph, connected to a photomultiplier, amplifier and recorder, makes possible the detection of quantities of nitrogen as small as 0. lug. A method has been worked out which, using noble gases as carriers, will be used for the analysis of 14N/15N ratios in fractions of nitrogen metabolites containing fractions of a microgram of nitrogen isolated from short term ion uptake experiments.

2. ENTOMOLOGY

Since its inception in 1964 the Entomology laboratory has been primarily concerned with the control of the Mediterranean Fruit Fly (Ceratitis capitata) by the sterile insect release method and has placed emphasis on problems concerning mass-rearing, radiation, and the development of packaging method for shipment and suitable for ground and aerial release of sterile insects. In order to assist in the initiation of eradication schemes, the laboratory has concentrated on the development of cheap rearing methods and adequate release techniques for insects, making use of rearing facilities in the laboratory basement to the maximum extent.

2.1. Mediterranean fruit fly

2. 1. 1. Rearing

The first diet suitable for mass-production of the Mediterranean fruit fly was developed in the USA and used dehydrated carrot as the VIENNA AND SEIBERSDORF 65 major nutrient. Since the cost of this diet was prohibitive for sterile male programmes in developing countries, cheaper diets have been developed by scientists at Seibersdorf, in Israel and in Central America. These diets are based on wheat bran or sugar-cane waste (bagasse) plus wheat germ and are about one tenth as costly as the dehydrated carrot diet.

FIG. 18. Disposable pressed-cardboard egging cages.

To further reduce the time spent between project inception and execution a start was made on designing fruit fly production kits so that mass rearing programmes may be set-up quickly and efficiently with a production sufficient to meet the particular situation. These production kits, rated in units of millions of flies per week, will include such essentials as inexpensive disposable cages, appropriate formulae for larval rearing diets, larval rearing units, necessary utensils and ulti- mately cheap prefabricated housing designed to meet the needs of the particular climate area where the rearing facility might be set-up. In 1967 inexpensive disposable pressed cardboard egging cages were prepared (Fig. 18). These were thoroughly tested and used exclusively in the summer mass-production when over 200 million eggs were produced. Larval rearing cabinets permitting maximum utilization of space with a minimum expenditure of labour were designed and tested (Fig. 19). More than 40 million fruit fly pupae were produced using these cabinets. Further efforts are being made to simplify their construction and make them less expensive to produce.

2. 1. 2. Field studies, Capri and Ischia

The successful eradication of insect pests using sterile insect release methods depends to a great extent on environmental conditions. Climate, host availability, and degree of isolation of the area under consideration are some of the factors which must be evaluated before the initiation of a programme. 66 VII. AGRICULTURE

FIG. 20. Shipping containers for air-freighting pupae. VIENNA AND SEIBERSDORF 67

As a result of a recommandation of a Panel on Radiation, Radio- isotopes and Rearing Methods in the Control of Insect Pests in Tel-Aviv in October 1966, a co-operative international programme involving the Italian Atomic Energy Agency, the Italian Ministry of Agriculture, 'the Israel Atomic Energy Commission and the Seibersdorf Laboratory was initiated in February 1967 on the Island of Capri, Italy. A nearby island, Ischia, served as a control. The Seibersdorf Laboratory initiated and scientifically directed the programme. In a six month period about 70 million fly pupae were produced, sterilized, colour marked and air freighted once weekly to Rome from Israel or Seibersdorf in specially designed shipping containers (Fig. 20). . Irradiation treatment of pupae normally took place early on the morning of despatch by air to Rome. Upon arrival there the pupal containers were taken to Capri where 25 000 pupae were packaged per individual paper bag containing sugar coated excelsior to provide food and resting places for the emerging flies. The bags containing pupae were held for two or three days in a darkened, temperature controlled room during which time the flies began to emerge from their puparia. The flies were ready for release into the field when the majority of them had emerged. The pupae were marked with a powdered fluorescene dye. Emerging flies became marked with the dye; thus it was possible to identify laboratory reared flies among recaptured specimens in the field. By using a different colour each week information on longevity and dispersal of the adult flies was obtained. The trapping of flies was accomplished using "dry" traps containing "Trimedlure" which is basically an attractant for the males.

Phase I: April-August, 1967

Although two successful releases were made using a helicopter, the main release method was from the ground. The paper bags were hung, usually on the branches of host bearing trees, and slit open (Fig. 21). Observations showed that released flies survived for more than one week but normally for less than two weeks. During this experiment the significant dispersal range of the flies was between 100 and 150 metres from their release point. Female laboratory reared flies seemed to have retained the ability to locate the most suitable host trees although these were not necessarily ad acent to the release site. Throughout this phase of the investigation (April-August) there was no indication of a native population of flies (based upon fruit inspection), with one exception. One isolated area with a few Mediterranean fruit fly infested fruit was found on Capri in an area which had been overlooked in previous release operations (subsequent releases controlled this situation). On the neighbouring island of Ischia, which was used as. a control, fly infested fruit were detected in increasing numbers during the same period.

Phase II: September-October, 1967

The island of Capri is traversed along its short axis by a mountain ridge. This ridge divides the island into two separate geographical areas Anacapri (upper) and Capri (lower) and forms a barrier to the natural movement of Mediterranean fruit fly populations, especially from Capri to Anacapri. Thus it was possible to conduct an additional test on the 68 VII. AGRICULTURE

FIG. 21. Ground release: paper bag hung on host-bearing tree and then slit open. effectiveness of the sterile insect release method by releasing sterile flies on one part of the island and using the other part of the island as an untreated control. In September and October releases of sterile flies were continued in the Anacapri area but not in the Capri area. Two months after the beginning of the experiment a careful inspection of the two test regions clearly indicated that the sterile fly release area on Anacapri (treated) was essentially free of infested fruit trees. Only one infested fruit was found at the perimeter of the experimental region. Meanwhile, in the Capri (untreated) area many fruit which had been heavily stung by wild flies were found. Since there was no quarantine these wild flies may have been imported from the mainland. The data are still being processed. However, this pilot experiment indicated that the release of laboratory reared sterile flies was able to prevent an outbreak of wild flies under the prevailing environmental conditions. It should be emphasized that because of the limited effective dispersal range of released flies a dense release pattern is essential to achieve eradication. Such a pattern would normally require the use of an aerial release programme. Procida

Population studies and trial releases of sterile flies were carried out in preparation for further experimental work in 1968.

2.2. Olive fly

The mass production of the olive fly, Dacus oleae (Gmelin), continues to present serious problems. Systems of egg production and collection previously developed are inefficient and costly. The larval rearing media are complicated, expensive and give low yields. Therefore, increased emphasis has recently been placed on mass rearing of the olive fly at VIENNA AND SEIBERSDORF 69

Seibersdorf. Progress has been made in improving cage design to better utilize the method whereby eggs are laid on a smooth plastic surface or on smooth plastic screen and subsequently fall into a container of water, from which they can be easily removed. This "free fall" method of egg collection has greatly reduced the labour involved in olive fly rearing. Less expensive and more productive larval media are being worked out. 2.3. Tsetse fly

Tsetse flies (genus Glossina) occur throughout the tropical regions of Africa where they are vectors of the disease "trypanosomiasis" (sleeping sickness). More than twenty species are recognized, their distribution depending on climate, vegetation and the occurrence of the larger vertebrate animals which provide their food. They are all viviparous, one fully developed larva being produced by each female fly at intervals of up to two weeks. Consequently the rate of reproduction of tsetse flies is extremely low compared with other insects. The adult flies feed exclusively on vertebrate blood. The major problem associated with implementation of the sterile male technique for tsetse fly control is the difficulty in economically rearing sufficient numbers of flies. Therefore, research has been initiated at Seibersdorf on the development of suitable artificial adult media for tsetse fly rearing. A limited amount of quantitative data on reproductive capacity and a "brain" hormone associated with digestion have been obtained in order to have a basis for comparison between flies fed their normal blood diet and flies fed on artificial diets through membranes.

2. 3. 1. Laboratory work and rearing facilities A tsetse fly rearing room has been provided with a 12 hour cycle of light alternating with 12 hours dark; an air conditioner and supplementary heating maintain a temperature of 25°C ± 1°C. A portable humidifier keeps the relative humidity at 75%. A small laboratory has been provided adjacent to the tsetse fly rearing room. Supplies of field-collected G. morsitans pupae are being received from Salisbury, Rhodesia; pupae of laboratory adapted G. morsitans are being sent from Lisbon, while G. austeni pupae are being received from Bristol. Initial high mortalities among emergent flies from September to November were attributed to insecticidal contamination and large amounts of atmos- pheric dust during building operations. Conditions have now improved and mortality among the flies has been reduced. The maintenance and feeding of all flies in Seibersdorf is similar to the technique used by Nash for G. austeni at Bristol20 in which flies are allowed to take blood meals from the ears of rabbits.

2. 3. 2. A quantitative evaluation of the reproductive capability of Glossina morsitans from two sources compared to the reproductive capability of Glossina austeni

Field caught adults of G_. morsitans digest their blood meals more rapidly than laboratory reared flies21 . Of special interest is the possi-

20 NASH, R., JORDAN, A., BOYLE, J., Trans. Roy. Soc. Trop. Med. and Hygiene, 60 (1966) 183-88. 21 LANGLEY, P. A. , J. Insect Physiol. 13(1967)477-86. 70 VII. AGRICULTURE bility that Lisbon G. morsitans have regained the digestive efficiency of the "field" fly. ' Recently it was suggested that approximately 30% of the blood meal ingested by fertilized G. morsitans females is directed towards the development of the larva^'in utero", the rest being necessary to satisfy the normal energy requirements of the parent fly22. Analysis of all pupae produced so far shows that the linear relationship between live birth weight and residual dry weight [R. D. W. = Live weight — (water + fat), and is largely protein] of these pupae is practically identical to that calculated previously for field collected pupae (Fig. 22). The previously calculated regression line has been drawn in for comparison. Similarly, the relationship between R. D. W. and fat content is in good agreement. The water content of all pupae produced so far has also been very consistent. Therefore, the live birth weight of our pupae is related to their total protein content (R. D. W. + protein equivalent of fat) in a linear fashion (Fig. 23). . Thus (i) the relative amounts of water, protein and fat are identical in the newly deposited pupae of G. morsitant and G. austeni, and (ii) the composition of the laboratory deposited pupae is the same as field deposited pupae of G. morsitans. A trend has been established which supports the contention that approximately 30% of the blood meal is utilized for the development of the larva in G. morsitans, while in G. austeni the percentage appears to be higher. G. austeni diverts more of its meal (45. 3%) to the developing larva than does G. morsitans from Rhodesia (32. 8%). This difference might be accounted for by the difference in size between the species. Only 2. 6 meals are necessary between larval deposi- tions in G. austeni compared with 4. 0 for G. morsitans from Rhodesia. Relevant data are given in Table XXII. Data on Lisbon G. morsitans are incomplete.

2. 3. 3. Elucidation of the nature of the "brain" hormone in tsetse flies.

Evidence has been obtained that activity of the neuroendocrine system controls the rate of digestion23. The nature of the hormone has not yet been determined but is thought by. some workers to be either a protein or polypeptide rich in sulphydryl groups, or to be cholesterol. Tsetse flies have been injected with 35S-cystine and, using scintillation counting, it has been found to be incorporated into the brain. Autoradio- graphy is now being used in conjunction with standard cytological techniques to investigate the site of incorporation of the 35S in the brain. A linear relationship exists between the size of the meal ingested and the quantity of midgut proteolytic enzyme secreted 24 hours later in G. morsitans24. Experiments have now been completed (a) to illustrate the linear relationship, thereby proving the efficacy of newly made up enzyme substrate, (b) on flies which took small meals and were then injected with the brains of flies which took large meals 3 hours previously, (c) on flies which took small meals and were then injected with suspensions of cholesterol in saline.

22 LANGLEY, P. A. , I. Insect Physiol. 14 (1968)121-33. 23 LANGLEY, P. A. , I. Insect Physiol. 13 (1967)1921-31. 24 LANGLEY, P. A., J. Insect Physiol. 12 (1966)439-48. VIENNA AND SEIBERSDORF 71

x Lisbon o Rhodesian • Bristol

FIG. 22. Relationship between live weight of newly deposited tsetse pupae and their residual dry weight (RDW) which is largely protein. The line is drawn from a regression equation calculated previously and is seen to be in good agreement with the present data.

x Lisbon o Rhodesian • Bristol

15,

..rfo* o% 0 o O

o- 2 5

o-MAr 20 Livt wtight (mg )

FIG. 23. Relationship between total protein content (RDW + protein equivalent of fat) and live weight of lewly deposited pupae. The regression has not yet been calculated. 72 VII. AGRICULTURE

TABLE XXII. REPRODUCTIVE CAPABILITY DATA OF THREE SPECIES OF TSETSE FLIES

G. austeni G. morsitans G. morsitans (Bristol) (Rhodesia) (Lisbon)

Mean wt. of pupae produced (mg) 20.5 24.3 24.3

Sample size 30 18 4

Mean size of parent flies 5.39 6.90 6.62

Sample size 10 6 1

Mean meal size (mg) 49.1 mg 52.3 mg -

Pupal protein/meal protein (fy) 45.3 32.8 -

Sample size 18 8

Mean No. meals per 2nd et seq, 2.6 4.0 interlarval period

Mean length of 2nd et seq. interlarval period (days) 9.3 11.0

Using G. austeni males, the linear relationship (a) was proved for this species. However, treatments (b) and (c) had no effect on the development of midgut enzyme activity. Further observations are, however, required before the results can be confirmed.

2.3.4. Future work

Having gathered quantitative data on the reproductive capability of tsetse flies through two of three generations in the laboratory, studies will be initiated on artificial diets, fed to flies through membranes. The quantitative data will then be utilized as one means of comparing the artificial diets with the normal blood diet of the tsetse flies.

3. PLANT BREEDING

Research on improved methods of mutation induction has been continued along the lines already reported25. Progress has been made in increasing the efficiency of ionizing radiations such as gamma radiation and fast neutrons as well as other mutagen treatments such as the combination of radiation and chemical mutagens. Investigations have been performed to find the optimum radiosensitive stage of mutation induction and to modify physiological damage and sterility in

25 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No.IT, IAEA, Vienna (1967) 50. VIENNA AND SEIBERSDORF 73 irradiated seeds after mutagen treatments. Results from these studies have been prepared for publication in international journals and proceedings. The papers are listed under the section listing publications. This work is of importance for developing new improved crop strains. At present investigations are being made on barley, wheat and rice.

3. 1. Barley projects 10 000 spike progenies from mutagen treated plants in 1966 were analysed in field experiments for mutations in plant characters of agronomic importance. Approximately 500 mutant lines were selected on the basis of the following agronomic characters: early flowering and maturity, shorter and stiffer straw, changes in size and number of kernels, fertility and disease resistance. The purpose was to establish what plant characteristics can be changed and improved by mutations and what methods of treatments are most efficient. The treatments for comparisons were selected on the basis of chlorophyll mutation tests which had been carried out in the greenhouse in the autumn of 1966. The 500 mutant lines will be tested again in field experiments in 1968. In 1967 approximately 100 new seed treatments, involving gamma rays, fast neutrons or chemical mutagens, were carried out and the seeds planted in the field. About 80 treatments yielded sufficient viable plants to be harvested for further mutation studies. Chlorophyll mutation tests of this material were started in the greenhouses at the beginning of September. Analyses of 60 treatments were completed by the end of the year and examination of the remaining plants is in progress. 10- 15 ofthe most promising treatments are being grown in field experiments during 1968. The erection of plastic greenhouses made it possible to check and compare a large number of treatments. Approximately 25 000 spike progenies or 500 000 plant seedlings were examined for chlorophyll mutations in the greenhouse during 1967. The field experiments were carried out at Harrach Plant Breeding Station near Bruck a/L.

3.2. Wheat projects As the cultivated wheat species and varieties are of a polyploid nature (tetra- and hexaploid), the results from diploid barley cannot directly be applied to wheat. On the basis of the results of mutagen treatments in barley, experiments with wheat were continued during 1967. 3500 spike progenies were grown in field experiments at the Fuchsenbigl Experi- mental Station. Approximately 100 mutant lines were selected for further observation and examination to find mutations of practical agricultural importance. New mutagen treatments of seeds with gamma rays, fast neutrons or chemical mutagens (EMS) were applied and the seeds planted in the field for comparative studies. Seed progenies from this material are being prepared for field experiments in 1968. A limited number of plants have also been tested for chlorophyll mutations in the greenhouse.

3.3. Rice projects The rice project started in 1966 has been continuing to service the FAO/IAEA co-ordinated rice mutation programme in the Far East. Rice breeding scientists were trained in the laboratory. 74 VII. AGRICULTURE

FIG. 24. Experimental rice paddies in the plastic greenhouse at Seibersdorf. High temperatures and humidity could be maintained throughout the summer.

The seedling culture techniques which have been developed26 for cereals in the growth chamber, were modified for rice. It was found that most rice varieties germinate and grow ideally when the growth chamber temperature is kept between 27 and 30°C. A number of experiments have been carried out to compare radiosensitivity of various rice varieties after gamma and neutron irradiation. A new method was developed for the application of chemical mutagens. The main results of these studies were presented at the 3rd FAO/IAEA Co-ordinated Meeting on the Use of Induced Mutations in Rice Breeding in Taipei, June, 1967, and are published in the Report of the meeting27. Experiments were started in the Spring of 1967 to study mutagenic efficiency of gamma and fast-neutron irradiations. Two of the most effective chemical mutagens (EMS and DES) were also included for comparison, using the new method of treatment that was developed in the laboratory.

See Mutations in Plant Breeding (Proc.Panel Vienna, 1966), IAEA, Vienna (1966) pp.271. 27 Rice Breeding with Induced Mutations, Technical Reports Series No. 86, IAEA, Vienna (1968) pp. 155. VIENNA AND SEIBERSDORF T5

With the co-operation of ORKI, Hungary, the seeds were grown in the field at their experimental station in Szarvas. This first generation grew well and was harvested in October. The seed progenies will be tested in the greenhouse for chlorophyll mutation during the Spring of 1968 in order to select the best method of treatment for the field experiments in 1968, Experiments with rice were also carried out at Seibersdorf. Aplastic greenhouse was put up and rice paddies were prepared. Seeds of rice varieties from Asia, Europe and Latin-America were irradiated and planted out. The rice grew well in the plastic greenhouse in which the necessary high temperature and humidity could be maintained throughout the summer months (Fig. 24). The Hungarian varieties were the most successful as they were best adapted to the period of daylight at Seibersdorf. The successful growing of rice at Seibersdorf greatly assisted the project and made possible a training programme,

3.4. Neutron seed irradiation programme

An important part of the co-ordinated programme on the neutron irradiation of seeds has been the construction of a fast-neutron irradiation facility for swimming pool reactors. This facility was installed in the Austrian swimming-pool reactor, ASTRA, at the end of December 1966. In 1967 the laboratory was actively engaged in experiments on physical and biological dosimetry, comparative radiosensitivity of various species and varieties to gamma and fast-neutron irradiation, and the genetic effects of fast neutrons on chromosome aberrations and mutations. The results of these investigations have been published.28

3.5. Radiation services

The laboratory services, which include irradiation treatments of seeds, and advice and guidance on the application of ionizing radiations in plant breeding for Institutes and scientists in Member States, have increased considerably in 1967. Services have been provided for research contractors, for co-ordinated mutation research projects and for the Technical Assistance plant breeding projects. In addition, however, a large number of plant breeding institutes throughout the world have sought assistance. Following requests from FAO, radiation services have been provided for FAO plant breeding projects in Asia, Africa and South America. Special mention should be made of the FAO Near East Wheat and Barley Improvement and Production Project and for which co-operative projects have been developed in 1967. In 1967, 268 seed irradiation service treatments were carried out on 124 varieties of crop species from 26 laboratories in different countries in response to requests. These service treatments involve a great deal of work as much time is required when determining the correct radiation dosages for such a great variety of crop plants.

28 Neutron Irradiation of Seeds, Technical Reports Series No. 76, IAEA, Vienna (1967). Neutron Irradiation of Seeds II, Technical Reports Series (in press, 1968). VIII. NUCLEAR ELECTRONICS SERVICE AND DEVELOPMENT

1. GENERAL

The Electronics Section designs and develops measurement and control equipment specially suited to the needs of the Agency's laboratory and which is not available commercially. The section also maintains and services electronic equipment in the laboratory. In addition to smaller items like a 1 kHz sinewave normal frequency to 500 Hz pulse converter (to drive timers), high voltage power supplies to drift germanium detectors, a special programmer for a sample changer and a kicksorter, two deadtime circuits fitting USAEC norms, 3 pre- amplifiers for scintillation detectors and two pre-amplifiers for germanium detectors (cooled and uncooled), the following major item was developed.

2. PROGRAMMABLE COMPUTER INTERFACE

This apparatus works together with 4?r -/3 —/ coincidence electronic system and a computer. It serves to control a sample changer which, by a feed cam actuation, transports individual sources to be measured from a store magazine containing 50 sources into a 4it gas flow proportional counter. The sources are on Vins-foil of surface weight ~ 50 jug/cm2 tensioned by a metal transport ring. After counting, the sources are transported to another store magazine and stacked by a lift. A standard source and an empty source carrier (for background measurements) are fixed to the transport ring and can be counted any time between individual source measurements. The instrument can be operated by hand or controlled by the computer. The following controls are placed on the front panel: a signal-button for "power", a signal button for "start", a signal button each for "standard", "source" and "background", a signal button "clear", a mode-switch for "Autom. ", "Man. Comp.Free", "Man. Comp. Inh. ", a pilot light each for "HV on" and "Mag. Empty".

Operating principle (Fig. 25)

A_. _ _Mode_ s witch in J^o^ition "JVutorm ^

When the instrument is switched on, the d. c. supply voltages (+ 12 V and - 12 V) are provided for the digital elements (placed on plug-in printed circuits) and other supply points. The lamp L8 lights up. A relay delayed by about 0. 3 seconds on board 10 receives voltage through Se and flips all FF's into non-operating position by means of a reset'pulse viapin F. By means of another relay on board 10, the a. c. line of the motors is switched on. During the delay time of the first relay the timing condenser of the timing unit (TU) on board 5 is charged and is thus in the non-operating position. As long as the start button has not been operated the three recipient FF's on board 3 are blocked by a blocking voltage delivered by pin K. It is also useless to operate

76 VIENNA AND SEIBERSDORF 77

the "clear" button since its working contact is interrupted by the start relay. When pressing the "start" button the relay SR is switched on and is connected to + 12 V via a holding contact on pin T of board 13 and it thus remains switched on. Lj (start) lights up, the blockings are lifted and the recipient FF for background (board 3) is flipped. The switch- over blocks the remaining two FF's (source and standard) and flips via pin Y on board 2a the FF which switches lamp L4 (background) to the flash generator. By means of a contact on the start button switch A, B or D is operated, depending on the position of the sample changer. In this way the FF's of the respective motor on boards la, lb, lc and Id are flipped, the appropriate a. c. -gate on board 8 is opened and the appropriate motor starts to operate. The cycle ends as is described in the following under order "background" and the computer receives the signal to start. The remaining programme is now determined by the computer. Depending on the programme, the following orders maybe received in any sequence:

a. Order "background"

The order pulse (0 to 12 V) reaches pin W of board 3 via a zener diode (for voltage restoring) and via Sc. It flips the appropriate FF which in turn blocks the remaining two FF's on board 3 and switches on lamp L4 (background) via pin Y on board 2a. At the same time a pulse from pin A (board 3) switches on the flash generator via pin M, board 2b, closes the "normal" gas valve via pin B, board 5 (this normal gas valve delivers the amount of gas in the flow counter necessary for counting), and switches on the proportional counter motor M2 via pin S, board Id. Simultaneously with the flipping of the normal gas valve FF, a relay circuit is opened via pin Y, board 4 and by its contacts via pins X and Z, board 7, an inhibit voltage (+ 12 V) is switched to the computer. This blocking is indicated by lamp L10 (inhibit). When the proportional counter is fully opened the proportional counter motor is switched off by the two way switch C via pin Y, board Id and at the same time the transport motor Mj is switched on via pin E, board lc. This motor turns the transport ring until the transport opening for the source is placed exactly under the store cam. Switch E which is operated by the transport ring now switches off the transport motor via pin Y, board lc and switches on lift motor M4 via pin E, board lb. This motor stacks any source which has been transported in the store cam. Upon completion of this operation switch B switches off the lift motor via pin Y, board lb and switches on the transport motor again via pin X, board lc. This motor continues to operate until the background ring has reached the proportional counter. Any switches which may have been operated by the transport ring before do not have any effect since the corresponding FF's are electrically blocked by order FF. Now the transport motor is switched off by switch G via pin R, board lc and the proportional counter motor switched on via pin J, board Id. When the proportional counter is closed, the proportional counter motor is switched off by D via pin E, board Id and the valves for flushing gas (necessary to remove the air from the proportional counter quickly) and for normal gas are opened via pin R, 78 VIII. ELECTRONICS

FIG. 25. Diagram of programmable computer interface designed and built at Seibersdorf.

80 VIII. ELECTRONICS board 5 through the appropriate a. c. gates. The normal gas valve FF connects a delayed relay to voltage (via pin N, board 7) which after 20 seconds switches on the high voltage for the proportional counter. (This is indicated by pilot light L7, "HV on". ) When the flush time of about ,40 sec has elapsed, the timing unit (TU) flips into non-operating position. This flipping causes the following: the FF's on board 3 are reset via pin B and that of board 2d via pin W. The corresponding FF on board 2b blocks the flush generator on board 11 via pin T. Further- more via pin Y, board 4 a relay is excited which switches off the inhibit voltage of the computer and supplies a ready pulse to the computer with 10 msec delay via pin E, board 4. The computer carries out its work and then gives the next order to the instrument. This may for instance be:

b. Order "standard"

The order pulse reaches pin Y, board 3 via switch Sa and flips the appropriate recipient FF. This blocks the other two FF's and connects L5 to the flush generator via pin S, board 2a and the flush generator is switched on by a pulse at pin R, board 2b. The remaining FF's on board 2a and 2b are reset via pin R. The remaining process is the same as above with the only difference that the proportional counter is closed when the ring containing the "standard" source has entered it.

c. Order "source"

The order pulse reaches pin N, board 3 via Sb and the flip operation of the corresponding FF causes the appropriate functions on boards 3, 2a and 2b. Further operations including the switching on of the transport motor after stacking remain the same as above, however, the transport motor is stopped by switch H via pin H, board lc, when the transport opening for the "source" is under the feed cam. The feed cam motor M3 is switched on via pin E, board la. After removal of the source from the magazine to the transport ring the feed cam motor is switched off via pin Y, board la and the transport motor switched on again via pin D, board lc. The transport motor moves the transport ring until the source is in the proportional counter. The latter is closed and the following operations remain the same as described above.

switchi5_P.osition"Man. Comp. Free" The individual cycles correspond exactly to those described above, however the order inputs are disconnected from the computer and connected to the signal buttons "background", "standard" and "source". Orders are given by hand by pressing the appropriate button.

Operation as under B above; however the inhibit voltage remains connected to the computer and blocks it.

D. F ur t her^ Jat ions When pressing the "clear" button, a cycle which stops the sample changer after stacking may be started in any position of the mode VIENNA AND SEIBERSDORF 81 switch and in any operating position. In this final position it is, for instance, possible to remove the transport ring for cleaning purposes and to put it in again. In more detail this operation is caused by the following. By pressing the button "empty" a FF flips via pin S on board 2c. It switches on a relay via pin M, board 6 and pin V, board 13 respectively. At the same time the excitation of the start relay is interrupted; it will be de-energized and the lamp LI is turned off. While the proportional counter is closed the normal gas valve is closed by pin R, board 13, via pin D, board 5 and the proportional counter motor is switched on via pin D, board Id. The timing condenser is connected from TU to + 12 V via pin E, board 13 and thus the TU is immediately brought into the non-operating position. The flushing gas valve is thereby closed and the inhibit signal is switched on via pin Y, board 4. The "clear" lamp L2 is connected to the flushing generator via pin T, board 13. The cycle continues until stacking has been completed. The transport motor, however, is not switched on as the appropriate FF is blocked via pin A, board lc. The sample changer remains in the non-operating position until it commences its new programme with a "background" cycle initiated by pressing the "start" button.

E. "MaJ[az ine _empt y"

When the last source has been removed from the feed cam magazine, a shield is taken off a light barrier. This light barrier flips a FF via pin C, board 4 and pin Y, board 2c respectively. This FF switches on lamp L6 (mag. empty) via pin A, board 4, blocks order FF for source via pin L, board 3 and moves the order "source" to FF "clear" via pin P, board 2c. Thus a "clear" cycle is started. Other orders previously received are however normally executed. An interruption in the light barrier lamp circuit leads immediately to a clear cycle (signal at pin B, board 2c). When operating the "mode switch" the voltage at pin R, board 10 is shortly interrupted by Se . This causes all FF's to reset as is the case when switching on the power switch by the delayed relay on board 10. When switching off the instrument the inhibit order remains connected to the computer. IX. ADMINISTRATIVE MATTERS

1. TRAINING

1. 1. International advanced training course on the bioassay of radionuclides

This training course was in some ways a follow-up of an elementary course on the same topic held at the Agency's laboratory in 1963. While the number of applicants for the earlier course had been rather small, so that nearly all who applied could be admitted, on this occasion thirteen candidates, the maximum number which could be accepted both for financial reasons (funds available for the course were very limited) and for considerations of working space in the laboratory, had to be selected from the 41 applications. Candidates from Austria, Bulgaria, Canada, Czechoslovakia, Ecuador, India, Netherlands, Norway, Peru, Poland, South Africa, Turkey and the United Arab Republic were selected for the course. All the chosen candidates who came to the laboratory had at least a little and many had considerable experience in the field of bioassay methods. The director of the course, Dr. A. Morgan, came from the UK and one lecturer. Dr. Butler, from Canada: all the other lectures were provided by Agency staff members, who were also responsible for the preparation and execution of all laboratory experiments. The time was fairly equally divided between laboratory periods and lectures. Tuition covered biological properties of and determination methods for radioactive isotopes of strontium, caesium, iodine, calcium, hydrogen, uranium, thorium and plutonium. Detailed procedures were given to enable the participants in the course to calculate body burdens from data obtained in urine analyses. They were also given an opportunity to inspect the neutron irradiation facilities at the Seibersdorf reactor and to spend a day at the whole-body counting laboratory.

1.2. In-service training

Ten fellows received training in various fields: one (from Hungary) in low-level radiochemistry; five (from Ceylon, Japan, Poland, Taiwan and Thailand) in mutation breeding; two (from Thailand) in crop mutation isotope techniques; and two (from Turkey and Tunisia) in hydrology.

2. LABORATORY EQUIPMENT DONATED BY GOVERNMENTS OF MEMBER STATES

(a) The French Government donated calibration equipment for radioactive solutions at a total value of about US$ 35 000. (b) The Government of Romania donated three survey meters and scalers at a value of about US$6000. (c) A scale laboratory at a value of US$348 was donated by the Italian Government.

82 VIENNA AND SEIBERSDORF 83

3. FINANCE

The budget

For the financial year 1 January to 31 December 1967, the Laboratory had at its disposal funds totalling US$ 940445. Of this sum, $627 645 were drawn from the Agency's regular budget, $ 174 000 transferred from the General Fund (voluntary contributions), and $ 138 800 represented direct income to the Laboratory from sales of radioactive standards and services rendered to Member States, and savings on previous years. The income of the Laboratory includes $25 692 for the distribution of radioactive standards, $5410 for re-imbursable research work for the United States Atomic Energy Commission, $7810 for the design and construction of an absorbed dose calorimeter for a Member State, and $21415 for miscellaneous services rendered.

Expenditure

Total expenditure and obligations in 1967 may be summarized as follows: US$

Salaries and other staff costs 607 745 Duty Travel of staff 3 060 Scientific equipment 86 864 •Scientific and technical supplies 76 762 Common services and non-technical supplies • 97 932 TOTAL $ 872 363

A summary of total costs of the various programmes of work of the laboratories in Vienna and Seibersdorf during 1967, including depreciation charges for the usage of capitalized equipment and fixed installations, is given below. The breakdown of costs follows the arrangement of descriptive text on the laboratory's work. The total costs exceed the actual obligation of $ 872 363 by $42 614. This difference is due to amortization costs of previously acquired scientific equipment, which is higher than the amount spent for the acqui- sition of new equipment.

(A) Standardization of measurement and of analytical methods related to peaceful applications of nuclear energy

(i) Calibration of Radionuclides Development of calibration apparatus $ 27 266 Distribution of calibrated radioactive samples 33 398 Participation in intercomparison programme 14 671 (ii) Techniques Associated with Standardization Fabrication of Li-drifted germanium detectors 21 159 Improvement of methods 49 985

(iii) Neutron Fluence Measurements 29 644 84 IX. ADMINISTRATIVE MATTERS

(iv) Radiation Dosimetry Calorimetric measurements 11 326 Ferrous sulphate dosimeters 4 205 Lithium fluoride dosimetry 5 146

(v) Analytical Chemistry Reference materials (uranium ores) 28 281

(vi) Trace Element Analysis 24 926 Total for (A) 250 007

(B) Services to member states on request 14 046

(i) Low Level Radioactivity (LOWRA) Quality Control 56 388 Programme 5 631 (ii) Studies on Decompositon under Radiation 18 738 (iii) Purity of Commercial Radiochemical Preparations 64 776 (iv) Support to the Agency's Safeguards Programme 2 469 (v) Meteorite Service 3 423 (vi) Medical Bio-Chemistry Total for (C) 151 425

(D) Nuclear techniques in hydrology

(i) Improvement of Methods 7 649

(ii) Determination of Isotopic Composition of Natural 19 244 Water 14 818 (iii) Surface and Groundwater Investigation 16 609 (iv) Analytical Services to Member States 22 186 (v) Participation in the IHD

(vi) OxygeAnalytican Isotopil Methodc Compositios for Hydrologn and Developmeny t of 54 593 Total for (D) 135 099 VIENNA AND SEIBERSDORF 85

(E) Nuclear techniques in medicine

(i) Development of Methods and Instruments Medical activation analysis ' 20 704 Radioisotope scanning 19 374 Whole-body counting 10 930

(ii) Support to other Agency's Activities 15 804 Total for (E) 66 812

(F) Nuclear techniques in agriculture

(i) Soil Fertility, Irrigation and Crop Nutrition Co-ordinated rice project 31 091 Co-ordinated maize project 20 170 Co-ordinated programme of plant nutrient supply and movement in soil, related to rice, maize and wheat projects 20 501 Co-ordinated research programme on tree crop fertilization 16 981 Determination of N-15 concentration in biological materials 17 330

(ii) Entomology General methodology including direct support to field studies 15 162 Mediterranean fruit fly 25 281 Olive fly 842 Tse-tse fly 6 674

(iii) Plant Breeding General methodology 17 838 Barley projects 4 166 Wheat projects 1 672 Rice projects 4 839 Radiation services 2 282 Total for (F) 184 829

(G) Nuclear electronics service and development

(i) Construction of Absorbed Dose Calorimeter for a Member State 7 445

(ii) Development of Apparatus and Services 8 934 Total for (G) 16 379 86 IX. ADMINISTRATIVE MATTERS

(H) Training and publications

28 862 16 678

50 840 96 380

OVERALL TOTAL COSTS 914 977 Less depreciation charges for capitalized equipment exceeding expenditures for equipment purchased during 1967 42 614

9$ 872_363_ TOTAL EXPENDITURE AND OBLIGATIONS ======

4. PROFESSIONAL STAFF OF THE LABORATORY

The staff of the IAEA Laboratories are under the supervision of the Division of Research and Laboratories, Department of Research and Isotopes. In 1967, the professional staff members were:

HARBOTTLE, Garman* (United States of America)

Born 1923; B. S. California Institute of Technology; Ph.D. Columbia University.

A EC Fellow (1951-1952), Guggenheim Fellow (1957-1958), Brookhaven National Laboratory, 1949-1965. Joined the IAEA in September 1965.

Director, Division of Research and Laboratories, until November 1967.

SANIELEVICI, Alexandre* (Romania)

Bom 1899; University of Bucharest, University of Jassy, Paris University (Sorbonne); M. Sc., D. Sc. (physics), Member of the Academy of the Romanian People's Republic.

1931-1940 Research Associate, Institut du Radium, Paris; 1945- Professor of Nuclear Physics (Radio- activity), University of Bucharest; 1950- Head, Department of Nuclear Spectroscopy, Institute of Atomic Physics, Bucharest. Joined the IAEA in May 1958.

Deputy Director, Division of Research and Laboratories, until August 1967.

GRINBERG, Boris * (France)

Born 1909; Ing. de l'Ecole de Physique et Chimie. Docteur des Sciences Physiques. Head, Metrolo- gical Laboratory CEN de Saclay. Professor, Conservatoire des Arts et Metiers, Paris, and Institut National en Sciences et Techniques NuclSaires, Saclay. Joined the IAEA in November 1967.

Director, Division of Research and Laboratories.

COOK, Gerald B. (United Kingdom)

Bom 1921; University of Birmingham, University of Cambridge; B. Sc., Ph. D. (chemistry).

1944-1947 Member, Joint Canadian-British Atomic Energy Project Montreal, Quebec and Chalk River, Ontario, Canada; 1947-1953 Chemistry Division, AERE, Harwell, UK; 1954-1960 Head, Chemistry Group, Isotope Division, AERE, Harwell. Joined the IAEA in May 1960.

Head, Chemistry Section; in charge of the Seibersdorf Laboratory.

* Working within the Scientific Secretariat of the Agency and charged with certain supervisory functions for the Laboratories. VIENNA AND SEIBERSDORF 87

BEN HAIM, Aharon (Israel)

Born 1932; Technische Hochschule, Vienna; Diplom-Ingenieur (physics); Dr. techn. sc. (physics),

1959-1960 Staff member "Technion", Israel Institute of Technology (Haifa, Israel). Joined the IAEA in February 1962.

Physicist responsible for the operation of the whole-body counter, working mainly on gamma ray spectroscopy and its applications to the dosimetry of Thorotrast, until September 1967.

BROESHART, Hans (The Netherlands)

Born 1924, Amsterdam; Agriculture University Waageningen; Dipl. Eng. and Ph.D. (agriculture).

1948-1950 Assistant, Laboratory of Soils and Fertilizers, Waageningen; 1950-1958, Head, Soil Science Section, Research Department of Unilever Plantations, Congo; 1958-1960 Principal Research Officer, Laboratory of Soils and Fertilizers, Waageningen. Joined the IAEA in 1961.

Head of the Laboratory Section of the Agriculture Division.

CAMERON, John F. * (United Kingdom)

Born 1929; Glasgow University; B.Sc.

1950-1962 U.K. A. E. A. Harwell; 1951-1952 Health Physics Division; 1952-1962 Isotope Division. Joined the IAEA in 1962.

Physicist responsible for the industrial applications of isotopes, until May 1967,

DINNER, Turgut Mustafa* (Turkey)

Born 1923; Technical University of Istanbul; M. Sc., Cir. Eng.

1962-1965 Assistant Professor, Middle East Technical University, Ankara, Turkey. Joined the IAEA in March 1965.

Hydrologist responsible for surface water studies.

DUDLEY, Robert A. * (United States of America)

Born 1926; Pennsylvania University, Massachussets Institute of Technology; B. A., Ph. D. (physics).

1951-1953 Fulbright Scholar, Medical Research Council, Hammersmith Hospital, UK; 1953-1955 Staff member. Division of Biology and'Medicine, USAEC; 1955-1956 Consultant to the Egyptian AEC; 1956-1960 Research Associate, Department of Physics, MIT. Joined the IAEA in 1960.

Physicist responsible for the whole-body counter and associated activities.

FLORKOWSK1, Tadeusz (Poland)

Born 1929; Academy of Mining and Metallurgy, Institute of Nuclear Physics, Cracow; Ph, D. (physics).

1950-1964 Staff member, Institute of Nuclear Physics, Cracow. Joined the IAEA in September 1964.

Physicist-responsible for tritium and carbon-14 laboratory work.

FRIED, Maurice * (United States of America)

Born 1920; Cornell University, Purdue University; B.Sc., M. Sc., Ph.D. (agriculture, soil chemistry).

1947-1948 Instructor in Agronomy, Purdue University; 1948-1960 Research Soil Scientist, US Department of Agriculture, Agricultural Research Service, Beltsville, Md; 1955-1960 Teacher US Department of Agriculture, Graduate School. Joined the IAEA in 1960.

Director, Joint FAO/IAEA Division of Atomic Energy in Agriculture.

* Working within the Scientific Secretariat of the Agency and charged with certain supervisory functions for the Laboratories. 88 IX. ADMINISTRATIVE MATTERS

GALATZEANU, loan (Romania)

Born 1925; Moscow University; Ph.D. (chemistry).

1957-1964 Staff member, Institute of Atomic Physics, Bucharest. Joined the IAEA in February 1964.

Radiochemist, responsible for investigating methods of analysis of commercial radioisotopes and labelled compounds.

GOLEB, Joseph (United States of America)

Bom 1920; B. Sc. (chemistry).

1947-1967 Staff member of the Argonne National Laboratory, USA. Joined the IAEA in April 1967.

Chemist in charge of optical spectroscopic analysis (nitrogen-15 and nuclear materials).

HOUTERMANS, Hans (Federal Republic of Germany)

Born 1919; University of GBttingen, Germany; Dipl. Phys., Dr. rer. nat.

1951-1958 Staff member, Isotopenlaboratorium, Gattingen; 1959-1960 Staff member, Max-Planck Institute for Physics, Munich. Joined the IAEA in 1960.

Head, Physics Section.

HORTON, Charles A. (United States of America)

Bom 1918; Cornell University, N. Y., University of Michigan, M. S., Ph. D. (chemistry).

1942-1944 Staff member Bell Aircraft Corp. , 1945-1949 Research Assistant, University of Michigan; 1949- Research chemist, Union Carbide Corp. Joined the IAEA in November 1966.

Analytical chemist responsible for analytical activities of the chemistry programme.

KEROE, Erich A. (Austria)

Bom 1926; Vienna University; D. Phil, (physics).

1950-1955 Collaborator in the Physical Institute (Electronics), Vienna University; 1955-1958 Consultant to several firms manufacturing nuclear electronic equipment. Joined the IAEA in 1958.

Head, Electronics Section.

KOEHLER, Wilfried (Federal Republic of Germany)

Bom 1932; University of Munich, Germany; Dipl. Phys., Dr.rer.nat.

1958-1966 Staff member, Research Reactor Station of Technische Hochschule MUnchen. Joined the IAEA in 1966.

Responsible for neutron flux density measurements.

LEE, Byung Hun (Korea) Born 1929; College of Technology, Seoul; Leicester College of Technology, England; B.Sc., Postgraduate diploma.

1955-1959 Instructor of Dongdok Women's College, Seoul; 1959- Staff member Korean Atomic Energy Research Institute. Joined the IAEA in September 1966.

Working in collaboration with the Hydrology Section on gamma-active tracers for water.

MALINOWSKI, Jerzy T. (Poland)

Bom 1923; Technical University Lvov; Technical University Gdansk; Institute of Nuclear Research, Warsaw; M. Sc, (chemistry), D.Sc, (math.-phys. sciences).

1956-1960 Chief, General Analytical Laboratory, Institute Badan Jadrowych, Warsaw. Joined the IAEA in 1965.

Responsible for analysis of reactor fuels for Safeguards. VIENNA AND SEIBERSDORF 89

MERTEN, Dietrich (Federal Republic of Germany)

Bom 1920; University of Bonn; D. Sc. (chemistry).

1953-1959 Head, Isotope Laboratory of the Research Centre on dairy products, Kiel; 1959-1960 IAEA scientific consultant. Joined the IAEA in 1961.

Inorganic chemist, responsible for the low-level radioactivity (LOWRA) programme and related intercomparisons.

MEYER, Georg (United States of America)

Bom 1928; B.Sc. in Geology.

Lawrence Radiation Laboratory, California, USA (1963-1966). Joined the IAEA in December 1966.

In charge of the preparation of environmental isotope hydrological data for computer storage.

MIDDELBOE, Victor (Denmark)

Bom 1920; Royal Veterinary and Agricultural College, Copenhagen, University of Copenhagen; Agronom, Lie. agro., Mag. sc. (physics).

1943-1944 Staff member, Farmer's Society, Odsherred; 1954-1956 Teaching and research and 1956-1966 Lecturer, in charge of isotope laboratory, Royal Veterinary and Agricultural College, Copenhagen. Joined the IAEA in April 1966.

Concerned with plant nutrient supply programme and the development of improved techniques for 15N determination.

MIGUEL, Manuel (France)

Born 1929; Ecole Centrale d'Electronique, Conservatoire National des Arts et MStiers, Paris.

1955-1960 Technical Assistant, CEA, Paris, and CEN, Fontenay-aux-Roses and Saclay. Joined the IAEA in 1960.

Physicist responsible for investigations into new counting methods and techniques.

MIKAELSEN, Knut M. (Norway)

Born 1920; Oslo University; M. Sc. (chemistry), Ph. S. (genetics).

1950-1951 Postgraduate Fellow, Cornell University, USA; 1951-1953 Research Fellow, Brookhaven National Laboratory, USA; 1953-1959 Senior Research Associate, The Agricultural College, Vollebekk (Norway); 1950- Professor, University of Bergen (Norway). Joined the IAEA in 1965.

Responsible for plant breeding and the genetics programme.

MONRO, John M. (Australia)

Born 1927; University of Adelaide; Ph.D.

1958-1963 Staff member, University of Adelaide, S. Australia. Joined the IAEA in April 1964.

Entomologist engaged in the rearing of the Mediterranean fruit-fly, in connection with the application of the sterile-male technique for insect population control and eradication, until March 1967.

MUELLNER, Theodora H. (Austria)

Bom 1926; University of Vienna; M. D.

1955-1962 Medical Staff, Allgemeines Krankenhaus, Vienna. Joined the IAEA in June 1962.

Engaged in the Thorotrast research project. Medical Physics Section.

NADEL, David (United States of America)

Bom 1925; B. A. Entomologist. Head of the Biological Control Institute, Rehovoth (Israel). Joined the IAEA in February 1967.

In charge of the Entomology Section, Agricultural Use of Nuclear Energy Laboratory. 90 IX. ADMINISTRATIVE MATTERS

NAGL, Hans (Austria)

Bom 1928; Technische Hochschule, Vienna: Dipl. Eng., Dr. Techn. Sciences.

1955-1960 Assistant, Institute of Experimental Physics, Technische Hochschule, Vienna; 1960- 1961 Teacher (physics and mathematics) Bundesgewerbeschule, Vienna. Joined the IAEA in 1961.

Physicist responsible for the development of calorimetric and other methods of radiation dosimetry.

NARANG, Ved Prakasch (India)

Bom 1935; B.Sc., M. Sc., Ph. D,

Joined the IAEA in July 1967.

Nuclear chemist, working on the calibration of E. C. nuclides. Determination of nuclear constants needed for radionuclide calibration.

NETHSINGHE, Douglas (Ceylon)

Bom 1928; University of Ceylon; B.Sc. (chemistry), Ph.D. (soil chemistry).

1951-1952 Research Assistant, Industrial Research Laboratories; 1952-1959 Research Assistant, Coconut Research Institute; 1959-1966 Soil Chemist, Coconut Research Institute. Joined the IAEA in October 1966.

Responsible for the tree crop fertilization programme.

PAYNE, Bryan R. * (United Kingdom)

Born 1927: University of Nottingham; B.Sc., A. R. I.e.

1950-1958 Senior Scientific Officer, Isotope Division, U. K. A. E. A., AERE, Harwell. Joined the IAEA in 1958.

Head, Hydrology Section.

PARR, Robert Middleton* (United Kingdom)

Bom 1938; University of Cambridge; University of London (Institute for Cancer Research); B. A., M,A. (physics, chemistry), Ph. D. (biophysics).

1962-1964 Resident Research Associate, Argonne National Laboratory, USA. Joined the IAEA in January 1965.

Physicist responsible for the development of activation analysis techniques and their application to biological and medical problems.

SUSCHNY, Otto (Austria)

Born 1924; Vienna University; D. phil. (chemistry).

1954-1958 Research Assistant, Radiochemical Department, Vienna University. Joined the IAEA in 1958.

Head, Low-Level Radioactivity Group.

TUGSAVUL, Aysen (Turkey)

Born 1938; Dipl. Eng. Chem.

Research worker at the Turkish Atomic Energy Commission, Nuclear Research Centre in Ankara. Joined the IAEA in March 1967.

Chemist, working on the LOWRA Project.

* Working within the Scientific Secretariat of the Agency and charged with certain supervisory functions for the Laboratories. VIENNA AND SEIBERSDORF 91

VASILYEV, Vadim (USSR)

Born 1920; University of Moscow; Diploma (physics).

1950-1953 Junior Scientific Collaborator, Institute of Physical Problems, Moscow; 1953-1966 Head of mass spectrometry group, Institute of Physical Chemistry, Moscow. Joined the IAEA 20 June 1966.

Physicist responsible for the operation and maintenance of the mass-spectrometer and the interpretation of results.

VETTER, Herbert* (Austria)

Bom 1920; Vienna University; M. D.

1951 British Council Fellow; Post-graduate Medical School (London); 1954 Research Fellow, Sloane Kettering Institute for Cancer Research, New York, USA; Assistant Professor, Vienna University. Joined the IAEA in 1958.

Division of Life Sciences, Medical Physics Section.

YEN, Chia Kuei (Taiwan)

Born 1926; B. Sc., hydrologist.

Taiwan Power Company, Taipeh (1955-1967). .Joined the IAEA in June 1967.

Collaborating on the programme of data compilation for computer storage of hydrological data: engaged in various field projects.

4.1. Temporary Staff

By courtesy of the Swedish Atomic Research Council, Mr. G. AhnstrSm worked in the Plant Breeding Section as a consultant for 6 months.

Mr. P. A. Langley (Special Fund) joined the Entomology Section in July 1967 to work on the rearing and physiology of tsetse flies.

Mr. M. Tzanakakis from Greece spent 2 months in the Entomology Section to work on production problems of olive flies.

Mr. J. Ketcheson from Canada arrived in November 1967 to spend 9 months of sabbatical leave with the crop nutrition Section to work on fertilizer nitrogen behaviour in soils.

5. PUBLICATIONS BY STAFF MEMBERS

AHNSTROM, G. , "Effects of oxygen and moisture content in fast neutron and gamma irradiated barley seeds", Neutron Irradiation of Seeds II, Technical Reports Series, IAEA, Vienna (1968, in press).

AHNSTROM, G., BURTSCHER, A., CASTA, J. , "Fast-neutron dosimetry in the seed irradiation facility, ASTRA reactor, Seibersdorf, Neutron Irradiation of Seeds, Technical Reports Series No. 76, IAEA, Vienna (1967) 87.

AHNSTROM, G., MIKAELSEN, K., "Life times of radiation-induced oxygen-sensitive centres in barley embryos soaked at different temperatures", Mutations in Plant Breeding II, (Proc. Panel, Vienna, 17-23 Sep. 1967), Technical Reports Series, IAEA, Vienna (1968, in press).

ALEKSIC, Z., BROESHART, H., M1DDELBOE, V., The effect of nitrogen fertilization on the release of soil nitrogen, Plant and Soil (1968, in press).

* Working within the Scientific Secretariat of the Agency and charged with certain supervisory functions for the Laboratories. 92 IX. ADMINISTRATIVE MATTERS

ALEKSIC, Z. , BROESHART, H., MIDDELBOE, V., Shallow depth placement of (NH4)2S04 in submerged rice soils as related to gaseous losses of nitrogen and fertilizer efficiency, Plant and Soil (1968, in press).

BELCHER, E. H., "New aspects of biomedical research with radioisotopes", Integration in Internal Medicine (Proc. IV Intern. Conf. Int. Med., Amsterdam, 1966), Excerpta Medica Foundation, Series 137, p. 266.

BURTSCHER, A., CASTA, !., "Facility for seed irradiations with fast neutrons in swimming pool reactors: A design study", Neutron Irradiation of Seeds, Technical Reports Series No. 76, IAEA, Vienna (1967) 41.

COOK, G. B., GOLEB, J. A., MIDDELBOE, V., Optical nitrogen-15 analysis of small nitrogen samples using a noble gas to sustain the discharge, Nature, Lond., 216 5114 (1967)475.

CZAKOW, J., COOK, G. B., KOSTAL, L., Comparison of the results of spectrographic trace determination in uranium, Chem. Anal. (Warsaw) 12 (1967)687.

DUDLEY, R.A., Statistically efficient use of reference pulses in spectrometer stabilization, Nucl. Instrum. Meth. 46 (1967)116.

DUDLEY, R, A., BEN HAIM, A., Assay of skeletally-deposited 90Sr in humans by measurement of bremsstrahlung, Health Physics (1968, in press).

DUDLEY, R. A., BEN HAIM, A., Comparison of techniques for whole-body counting of gamma-ray emitting nuclides with Nal(Tl) detectors. I. Point sources in phantoms, and II. Distributed sources in phantoms and humans, Phys. Med. Biol. (1968, in press).

DUDLEY, R. A., Statistically optimum radiation counting: a criticism of the Bradley-Marks background suppression technique, Physics in Med. and Biol. 11 (1967) 313.

FISCHER, P., GOLOB, E., KUNZE-MUEHL, E. , BEN HAIM, A., DUDLEY, R. A. , MUELLNER, T., PARR, R. M., VETTER, H., Chromosome aberrations in peripheral blood cells in man following chronic irradiation from internal deposits of Thorotrast, Rad. Res. 29 (1966)505.

FLORKOWSKI, T., Radiometrische Verfahren bei Prospektion and Gewinnung von Kohle und Erz, Atomwirtschaft 12 5 (1967) 247.

GALATZEANU, I., ANTONI, F. , "Effets des rayonsgamma (cobalt -60) sur la vitamineBe et l'acide follique", Radiosterilization of Medical Products (Proc. Symp. Budapest, 1967), IAEA, Vienna (1967) 33.

GOMEZ-CRESPO, G., VETTER, H. , The calibration and standardization of thyroid radioiodine uptake measurements. Int. I. appl. Rad. Isotopes 17 (1966)531.

HALEVY, E., PAYNE, B. R., Deuterium and oxygen-18 in natural waters: analyses compared. Science 156 3775 (1967) 669.

HINE, G.J., Ch. 6, Sodium iodide scintillators, Instrumentation in Nuclear Medicine (HINE, G.J., Ed.), Academic Press, N. Y. (1967).

HINE, G.J., Ch. 12, Gamma-ray sample counting, ibid.

HINE, G.J., WILLIAMS, J.B., Ch. 14, Thyroid radioiodine uptake measurements, ibid.

BROWNELL, G. L., ARONOW, L., HINE, G. J., Ch. 16, Radioisotope scanning, ibid.

MYHILL, J., HINE, G. J., Ch. 17, Multihole collimators for scanning, ibid.

HINE, G.J., Evaluation of focussed collimator performance, II. Digital recording of line source response, Int. J. appl. Rad. Isotopes 18 (1967)815. VIENNA AND SEIBERSDORF 93

JAHNS, E., HINE, G.J., A line-source phantom for testing the performance of scintillation cameras, J. nucl. Med. (1968, in press).

HOLLAND, J., ANTONI, F., GALATZEANU, I., SCHULMAN, M., KOZ1NETZ, G., Effects of gamma irradiation (60Co) on the tetracyclines, Radiosterilization of Medical Products (Proc. Symp. Budapest, 1967), IAEA, Vienna (1967)69.

KONZAK, C. F., MIKAELSEN, K., SIGURBJORNSSON, B., BURTSCHER, A., Recommended standard procedures for irradiating, cultivating and measuring cereal seeds to determine the effects of neutron irradiation in the neutron-seed-irradiation programme. Neutron Irradiation of Seeds, Technical Reports Series No. 76, IAEA, Vienna (1967) 103.

LANGLEY, P. A., Physiological studies on the tsetse fly (G. Morsitans) in relation to the problem of laboratory maintenance, Paper presented to Panel on Control of Livestock Insect Pests, IAEA, Vienna, 1967.

LEICKNAM, J.P. , FIGDOR, H.C., KEROE, E.A., MUEHL, A., Transformation simple d'un spectrograph a plaques photographiques en spectrometre enregistreur utilisable notamment pour le dosage isotopique de 1'azote, Inter. J. appl. Rad. Isotopes (1968, in press).

LEICKNAM, J.P. , MIDDELBOE, V., PROKSCH, G., Analyse isotopique de l'azote par spetrometrie optique pour de faibles teneurs en 1SN, Analyt. Chim. Acta (1968, in press).

MERZARI, A. H. , BROESHART, H., "The utilization by rice of nitrogen from ammonium fertilizers as affected by fertilizer placement and microbiological activity", Isotope Studies on the Nitrogen Chain (Proc. Symp. Vienna, 1967), IAEA, Vienna (1968) 79.

MIKAELSEN, K. , Research activities of the Plant-Breeding and Genetics Section of the Seibersdorf Laboratory, Mutation in Plant Breeding (Proc. Panel, Vienna, 1966), IAEA, Vienna (1966) 249.

MIKAELSEN, K., Protective effectiveness of cysteine, cysteamine and cystamine against gamma-radiation induced chromosomes aberrations at different stages of mitosis, Hereditas 58 (1968, in press).

MIKAELSEN, K., Comparison between chromosome aberrations induced by ionizing radiations and alkylating agents at different stages of mitosis in barley seeds, Mutations in Plant Breeding II (Proc. Panel Vienna, 1967), IAEA, Vienna (1968).

MIKAELSEN, K., Effects on seedling growth in barley seeds irradiated with fast neutrons. Neutron Irradiation of Seeds II, Technical Reports Series, IAEA, Vienna (1968, in press).

MIKAELSEN, K., AHNSTROM, G., LI, W.C., Genetic effects of alkylating agents in barley. Influence of post-storage, metabolic state and pH of mutagen solution, Hereditas, 58 (1968, in press).

MIKAELSEN, K., CASTA, J., Neutron-irradiation experiments with barley seeds in the ASTRA reactor (Austria), Neutron Irradiation of Seeds, Technical Reports Series No. 76, IAEA, Vienna (1967)63.

MIKAELSEN, K., NAVARATNA, S., Effects of post-treatments with buffer solutions on irradiated barley, Studia Biophysica 2 (1967) 139.

MIKAELSEN, K., NAVARATNA, S., Experiments with Mutagen Treatments in Rice, Technical Reports Series, IAEA, Vienna (1968, in press).

MONRO, J., The exploitation and conservation of resources by populations of insects, J. Anim. Ecol. 36 (Oct. 1967)531. _

NAGL, K. , MIKAELSEN; K., Mutation experiments in Durum wheat, Mutations in Plant Breeding II(Proc. Panel, Vienna, 1967), Technical Reports Series, IAEA, Vienna (1968, in press).

PARR, R. M., LUCAS, H. F., GRIEM, M. L., Metabolism of 232Th decay series radionuclides in man and other animals following intervascular administration of Thorotrast, Health Phys. (1968, in press). 94 IX. ADMINISTRATIVE MATTERS

VARELA, J. E., Applications of nuclear medicine to the study of blood disorders, Nuclear Medicine and the Practising Doctor (Gilder, S. S.B, , Ed. ),Documenta Geigy Series (1968, in press).

VETTER, H., Die Bedeutung der radioaktiven Isotope in der medizinischen Forschung, Die Therapiewoche 17, 50, 2056 (1967).

WENGER, P., BENGTSSON, L. G., DUDLEY, R. A. , GODFREY, B. E. , KARNIEWICZ, W., LENGER, V., NEWTON, D., Whole-body counting of persons containing 90Sr and 225Ra: an interlaboratory comparison, Health Phys. (1968, in press).

6. PAPERS PRESENTED AT SCIENTIFIC MEETINGS BY STAFF MEMBERS

BELCHER, E. H., "Applications of liquid scintillation counting", Symposium on Liquid Scintillation Counting, Teddington, England, October 1966.

BELCHER, E. H.,"Whole-body radioactivity measurement techniques as applied to the study of gastrointestinal absorption and excretion", Radioisotope in der Gastroenterologie, 3. Jahrestagung der Gesellschaft ftlr Nuclear Medizin in Lausanne, October 1965 (Hoffmann, G., Ed. ),F. K. Schattauer-Verlag, Stuttgart (1967).

BELCHER, E. H., "Report on distribution of reference 125I-labelled albumin and gamma-globulin", Meeting on the Coordination of Research on the Use of Radioisotopes in the Study of Malnutrition in Tropical and Sub-Tropical Regions, Vienna, October 1967.

BELCHER, E. H., "Report on intercomparisons of serum protein measurements", Meeting on the Coordination of Research on the Use of Radioisotopes in the Study of Malnutrition in Tropical and Sub-tropical Regions, Vienna, 1967.

COOK, G. B., GALATZEANU, I., Control of Radiochemical Purity of some 131I and 203Hg-labelled compounds, IAEA Report; Euratom Working Group on practical problems resulting from the use of "Radio- pharmaceuticals", Brussels, December 1967.

DAVIS, G. H., PAYNE, B. R. , DINNER, T., FLORKOWSKI, T., GATTINGER, T., "Seasonal variations in the tritium content of groundwaters of the Vienna Basin, Austria", Isotopes in Hydrology (Proc. Symp. Vienna, 1966), IAEA, Vienna (1967)451.

DAVIS, G. H. , DINNER, T., FLORKOWSKI, T. , HALEVY, E., PAYNE, B. R., "A combined environmental isotope approach for studiyng water resources in the developing countries". Int. Conf. on Water for Peace, Washington, May 1967.

DINNER, T., "Application of radiotracer methods in streamflow measurements", Isotopes in Hydrology (Proc. Symp. Vienna, 1966), IAEA, Vienna (1967) 93.

DINfER, T., DAVIS, G. H., Considerations of tritium dating and estimates of tritium input function, Int. Assn. of Hydro'geologists, Istanbul, September 1967.

DINf ER, T., HALEVY, E., "Current trends in the use of radioactive tracers in hydrologic investigations", Int. Conf. on Water for Peace, Washington, May 1967.

DUDLEY, R. A., A survey of radiation dosimetry in thorium dioxide cases, Conference on Distribution, Retention and Late Effects of Thorium Dioxide, Ann. N. Y. Acad. Sci. 145 Art. 3 (1967)595-607.

FISCHER, P., GOLOB, E., KUNDE-MUEHL, E., MUELLNER, T., "Chromosome aberrations in persons with thorium dioxide burdens", Human Radiation Cytogenetics, Proc. Int. Symp. held in Edinburgh, Oct. 1966 (Evans, H.J. , Court Brown, W.M. and McLean, A. S., Eds), North Holland, Amsterdam (1967).

HALEVY, E., MOSER, H., ZELLHOFER, O., ZUBER, A., "Borehole dilution techniques: a critical review", Isotopes in Hydrology, (Proc. Symp. Vienna, 1966), IAEA, Vienna (1967)531. VIENNA AND SEIBERSDORF 95

HALEVY.E., "Nuclear techniques in hydrological investigations in the unsaturated zone", Symp. on water in the unsaturated zone, Waageningen, June 1966.

HINE, G.J., "Sensitivity, depth response and resolution of multi-hole collimators", 13th Annual Meeting of the Society of Nuclear Medicine, Philadelphia, June 1966.

HINE, G.J. , "Investigations of collimator performance", Int. Nuclear Medicine Symposium, Radioactive Isotopes in the Localisation of Tumors, London, September 1967.

MALINOVSKI, J. , "Some remarks on precision and accuracy in mercury analysis", Expert Meeting on Mercury Contamination in Man and his Environment, Amsterdam 1967.

MERTEN, D., "Accuracy in low-level radiochemical measurements", Symp. on the Determination of Radio- nuclides in Material of Biological Origin, Harwell, April 1967.

MERTEN, D., The reliability of world wide monitoring in the light of accuracy in low level radiochemical analysis, UNSCEAR Meeting, Geneva, Aug. 1967.

MERTEN, D., Organizational aspects in the life sciences, CNEN Seminary, Rome, Sept. 1967.

MERTEN, D., "The reliability of world wide monitoring in the light of accuracy in low level radiochemical analysis", 4th RIS Symposium, Oslo, October 1967,

MERTEN, D., Analytical quality control, FAO/IAEA Training course on the use of Isotopes and Radiation in Animal Sciences and Veterinary Medicine, Brno, November 1967.

MERTEN, D., Analytical quality control, IAEA Int. Advanced Training Course on the Bioassay of Radio- nuclides, Seibersdorf, 1967.

NAD EL, D.J. , Progress report on eradication of the Mediterranean fruit fly by the sterile male technique on Capri, Italy, Paper to Panel on Radiation in the Control of Insect Pests: Ecological Studies, IAEA, Vienna 1967.

PARR, R. M., Information on Thorotrast dosimetry supplied by the radiochemical analysis of tissue specimens, Conference on Distribution, Retention, and Lage Effects of Thorium Dioxide, Ann. N. Y. Acad. Sci. 145 Art. 3 (Dec. 1967) 644-653,

PARR, R.M., BEN HAIM, A. , DUDLEY, R. A., FISCHER, P. , GOLOB, E. , KUNZE-MUEHL, E. , MUELLNER, T., VETTER, H., Chromosome aberrations in peripheral blood cells in man following chronic irradiation from internal deposits of Thorotrast", 3rd Int. Congress of Radiation Research, Cortina, Italy, 1966.

PAYNE, B. R., THATCHER, L. L., "The occurrence of tritium in precipitation and its significance in hydrological investigations", Int. Conf.. on Water for Peace, Washington, May 1967.

SUSCHNY, O., Aufgaben der Umgebungstlberwachung in internationaler Sicht, Meeting of the Austrian Health Physics Society, Vienna, November 1967.

SUSCHNY, O., Bioassay of strontium isotopes, IAEA International Advanced Training Course on the Bioassay of Radionuclides. Seibersdorf, 1967.

WILLIAMS, Pamela H., FLORKOWSKI, T., "Comparison of Triton-X emulsion systems with dioxane solutions in liquid scintillation counting of low-level tritium in water", Radioactive Dating and Methods of Low-Level Counting (Proc. Symp. Monaco, 1967), IAEA, Vienna (1967).

THE INTERNATIONAL LABORATORY OF MARINE RADIOACTIVITY, MONACO

I. INTRODUCTION

1. THE PROGRAMME

The field and laboratory research of the International Laboratory of Marine Radioactivity at Monaco in 1967 was concerned with problems related to the distribution of radionuclides in the sea as a function of time and space, the chemical behaviour of radionuclides of various chemical states in sea-water, the distribution and accumulation of radionuclides by the various components of marine biota, and the interchange of radioisotopes between the sea-bottom and the bottom- water.

2. INTERNATIONAL CO-OPERATION

As in the past, co-operation with the Centre Scientifique de Monaco and the Institut Oc6anographique de Monaco has been both smooth and effective, as it has been with the Laboratory of the Commissariat a l'energie atomique at Villefranche. This also applies to other Mediterranean institutes concerned with problems related to radioactivity in the sea, particularly the Laboratory of the Comitato Nazionale per l'Energia Nucleare, Fiascherino (Italy), and the "Ruder BoSkovic" Institute, Rovinj and Zagreb (Yugoslavia). With the latter joint investigations were made on the metabolism of EDTA (14C) in mussels, and the influence of the physico-chemical forms of zinc in sea water on its biogeochemical cycle was considered. Contacts have been set up with the newly founded Japanese "Special programme on the release of radioactive materials into the sea" with the aim of co-operating.

3. SCIENTIFIC MEETINGS ATTENDED

Thirteen international meetings and symposia were attended by scientists from the Monaco Laboartory during the period under review, among which the "international Symposium on Diffusion: Theories, Experiments at Sea", within the frame of the 14th General Assembly of the IUGG, Bern, where the Director of the Laboratory acted as convener, should be specially mentioned. Further sessions of the Intergovernmental Oceanographic Commission, Paris, the Special Session of the ACC Sub-committee on Marine Science and its Applications, and the meeting of the International Council for the Exploration of the Sea at Hamburg were attended, where general problems on the pollution of the oceans were discussed. During June and September two Contact Group Meetings between the laboratories of Fiascherino, Rovinj, Zagreb and Monaco were held at Fiascherino and Rovinj/Zagreb with a number of guests from other laboratories; various problems arising from the present laboratory programmes were discussed.

99 100 I. INTRODUCTION

4. VISITORS

About seventy scientists and dignitaries from sixteen different countries (Canada, Cuba, France, Hungary, Italy, Japan, the Netherlands, South Africa, Sweden, Switzerland, Turkey, United Kingdom, Uruguay, USA, USSR and Yugoslavia) visited the Laboratory and matters of mutual interest were discussed.

5. CO-ORDINATED RESEARCH PROGRAMME

The Monaco Laboratory assumed responsibility for the research contracts in the field of marine radioactivity studies during 1967, and prepared an agreement on a co-ordinated research programme. This programme is concerned with marine radioactivity studies and consists of two groups, one for 'Distribution and cycle of radionuclides and related trace elements in marine environment' and the second one for 'Behaviour of radionuclides in marine biota with their environment'. This programme was approved by the Committee and the Director General of the IAEA, and about 20 institutions, geographically widely distributed, have been contacted. Many institutes have already shown an interest in participating. It is believed that this co-ordinated programme, which is expected to start in early 1968, will play an important role in facilitating and stimulating the current research activities in the field of marine radioactivity studies by improving contacts between the various laboratories and by guiding some of the research efforts at the various laboratories to the ultimate goals pursued by the IAEA. II. RESEARCH

1. WORK AT SEA

The "Winaretta Singer", a small boat owned by the Musee Oceano- graphique, was available for the Laboratory 19 days during 1967 (seven cruises). Routine investigations near Monaco were carried out.

1. 1. Diffusion processes in the sea

The "Monaco Method" of studying small-range diffusion processes was reported in the International Symposium on Diffusion at Bern. The large range diffusion studies carried out with "Meteor" in 19661 were evaluated in collaboration with the German Hydrographic Institute, Hamburg. Figure 1 shows the distribution of the test material after 25. 5, 57. 5 and 101. 3 hours. The curves S are lines of equal concentration of the test material. The longitudinal extent of the patches is caused by strong winds, upto Beaufort 9-10. The maximum intensity SM decreases from 750 over 60 to 10 units. Figure 2 shows this decline on a logarithmic scale. The maximum concentration in these observations is inversely proportional to the -3 time cubed (SM oc t ). Papers and discussions during the International Symposium on Diffusion have confirmed this law in principle but the exponent varies for different experiments between 2 and 3. In the case of any accidental pollution of the sea by radioactivity the exponent 2 should be taken to estimate the decrease of SM since it would err on the side of safety. This means that the maximum intensity Sm2 at the time t2 can be estimated with the following formula:

when the maximum concentration Smi at the time ti is known, ti and t2 are calculated from the start of the pollution incident.

1.2. Penetration of isotopes into the sea bottom

The studies of penetration of radioisotopes into the sea bottom were extended to in situ experiments. With the help of divers the diffusion of chloride in the interstitial water of bottom sediments was measured. Figure 3 shows the method of measuring The apparatus is placed in shallow sea bottom sediment and removed two weeks later. The core is cut into sections and analysed in the laboratory. The results agreed with the laboratory measurements with the same sediments. Diffusion coefficients were found to be of the order of 0. 3 X 10~5 cm2/sec. This method is applicable up to a depth of 50 metres.

1 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No. 77, IAEA, Vienna (1967) 97-111.

101 102 II. RESEARCH

after 1, 2. 4, and 4.2. days. S lines of equal concentration, Sjj maximum concentration, in relative units.

1.3. Zooplankton observations

In winter months (until April) relatively dense populations of Euphausiids (Meganyctiphanes norwegica M. Sars. ) were observed close to the surface during the night in the coastal areas, and were collected by nets for laboratory experiments on bioaccumulation of 65Zn (see 2. 3. 1. ).

1.4. Organic aggregates

In 1967 a few measurements on the abundance and quality of organic aggregates were done to have additional data to the extensive investigations, carried out in the two preceeding years. The results fell in the range of those found previously. MONACO 103

1000 V l 500 \ SM 200 V 100

so y SM"-t- 3 20 \ 3 10 \ I 10 20 50 100 200 t Ch)

FIG. 2. The decrease of the maximum concentration SM as a function of time (logarithmic scale).

FIG. 3. Apparatus for "in situ" experiments to determine the diffusion coefficient in shallow sea bottom sediments.

2. WORK IN THE LABORATORY 2.1. Chemistry of sea water . The principal lines and objectives of the studies on the chemistry of sea water remained in 1967 similar to those stated in the Annual 104 II. RESEARCH

Report of 1966,1 except that more effort has been allocated to the analyses of trace elements in sea water samples. To solve the problems of chemical behaviour of radionuclides in a sea water medium, the determinations of various chemical forms of trace elements from water samples collected were compared with results from laboratory experiments using radioactive tracers in a sea-water medium. An outline of the progress of these studies in 1967 is given in the following sections.

2. 1. 1. Determination of trace elements in sea-water Chrom i u m_ and baJ. t

Since the methods for the determination of ionic cobalt, and tri- and hexavalent chromium in sea-water have been well established through the studies of the past years, these methods have now been used with many sea-water samples and fresh-water samples collected around Monaco to get some information concerning systematic variations of trace elements with the Seasons. More than 50 samples have been analysed for cobalt and 30 for chromium. Although the results obtained are localized values and, therefore, the conclusions derived from the results can hardly be generalized, some features deduced from the data may have significance from a general point of view, especially as far as the interaction between coastal sea water and fresh water is concerned. The sampling of water was usually done twice a month for sea water and once a month for fresh water at a sea station about 1 km south of Monaco and at a station at the Var river, respectively. The water samples were filtered as soon as possible after sampling and processed immediately afterwards. The analyses of suspended materials which were retained by HA type millipore filters were also carried out. In Fig. 4 the results for trivalent and hexavalent chromium in surface water are plotted against time. They may not be representative, because only single samples were analysed in several cases. However, some trials have proved that the data do not differ very much for results obtained from few kilometres apart. It seems that, as far as the soluble metal content is concerned, there are unlikely to be remarkable changes over short distances. The variations shown in the figure should be the results of very complex processes, such as advection of water masses, interaction of bottom material with water, biological activities, etc. However, it is unlikely that the peaks result from the fresh water flushing, since the fresh water normally has a lower trivalent or hexavalent chromium content, and the content of soluble species is fairly constant irrespective of the amount of suspended material contained. It is of interest to note the opposite tendencies between trivalent and hexavalent chromium, with some time lag. This may involve the oxidation-reduction processes in the sea-water medium. In the case of cobalt the picture should be different from that of chromium, since the fresh water can contain more cobalt than the sea water, with variations and therefore the variation of cobalt in fresh water will affect the sea water cobalt content. Although, as pointed out earlier, the features described cannot be generalized to apply to other areas, the main features may throw MONACO 105

1967

FIG. 4. Seasonal variations of trivalent and hexavalent chromium in surface sea-water collected from a station south of Monaco. some light on the understanding of the chemical processes that are taking place in a given locality.

Silver

The spectrophotometric procedures for the analysis of silver in sea water were tested by comparing the results obtained by these procedures with those obtained by neutron activation analysis, where the long-life silver isotope, 110Ag, was determined by y-spectrometry. The comparison proved that the correspondance of the results obtained using these two completely different techniques is satisfactory. The spectrophotometric method has been applied to a number of sea-water samples and some marine biological samples. The "abundance ratio" (concentration factor) of some mollusc species appeared to be around 3500. Since practically no information is so far available for the "abundance ratio" of silver in marine organisms, the work will be continued to establish the "standard abundance ratio" for certain groups of marine organisms. The neutron activation was carried out in collaboration with the nuclear chemistry group of EURATOM Center, Ispra, Italy.

2. 1.2. Laboratory experiments on the behaviour of radionuclides in sea-water medium

The importance of the kinetic studies of the chelate-formation process in a sea-water medium were stressed in the last Annual Report. The studies carried out in 1967 followed the same pattern but a different experimental technique, namely electrophoresis, has mostly been used. 106 II. RESEARCH

The results obtained by this technique were similar to those given by the adsorption method for trace amounts of cobalt in sea water. This correspondance strongly supports the hypothesis of the second-order reaction of the metal-EDTA chelate formation already described1. Studies on the colloid and particulate formation of ruthenium were started in 1967. It is difficult to obtain reproducible experiments due to the lack of knowledge of the chemical forms of ruthenium isotope in distributed solutions. Consequently, it seems imperative to first establish procedures for the carrier-free preparation of a definite chemical form of ruthenium in the tracer solution, so as to obtain reliable results on the preparation of various valency states of ruthenium and of nitrosyl complexes of ruthenium. This work is under way.

2.1.3. Conclusions Among the results obtained in 1967 the following points are considered to be significant from the practical point of view, although some of the results are only preliminary: (a) Through spring to winter the hexavalent chromium content of the surface layer of sea-water around Monaco always exceeds that of trivalent chromium. This is true at 50 m depth also. The chromium content of sea water around Monaco shows some systematic seasonal variations. The ratio of trivalent chromium to hexavalent chromium might possibly be considered an index of the oxidation-reduction processes for that locality. (b) The cobalt content of sea water around Monaco shows some seasonal variations which might be connected with the freshwater run-off. (c) The "abundance ratio" (concentration factor) of silver for some mollusc species appears to be around 3500. (d) The experiments on the chelation processes of cobalt with EDTA by electrophoretic techniques support the importance of kinetic factors .involved in the processes. (e) It has been proved that an accurate preparation of definite chemical forms of ruthenium is essential for obtaining reliable results from any kind of experiments on the behaviour of this element in sea- water.

2.2. Chemistry of sediments The main purpose of the work is to obtain background information on the general reactions of important radioisotopes with sea sediments. This knowledge should be more or less applicable for any type of sea sediment and should make possible some prediction of contamination based on the chemical and geological properties of a sediment and on the general reactions of the radioisotopes. The isotopes involved in the studies, given in Table I, have been observed in the sea by several other investigators. They are fall-out and neutron-induced isotopes of relatively long half-lives. The sediments used are collected for the laboratory by several national institutes from ocean areas shown in Fig. 5. There are usually two types of reaction for radioisotopes with sediments. First, isotopes are bound to sediment particles by sorption, co-precipitation or ion exchange, and second the isotopes migrate into a sediment. MONACO 107

'France — • Finland — .Germany —»Italy —»Japan —«Netherlands —-New Zealand — » U.S.A.— o U.S.S.R.— + Promised

FIG. 5. Map of the positions from which bottom samples, subsequently investigated in the Monaco Laboratory, were taken by oceanographic institutions of various countries.

2.2. 1. Sorption or binding

The most interesting results obtained in 1967 were details of the binding reactions of the ten radioisotopes mentioned in Table I with Mediterranean sediment, and information on the principles of diffusion in interstitial water of a sediment. The binding processes observed, regardless.of the isotope, show a tendency for obtaining a rather rapid equilibrium between sea-water and sediments, i.e. in terms of hours or some days. Depending on the isotope, more than 50% of the uptake is usually bound within minutes or hours. These results were obtained by a simple technique in which 10 mg sediment on a Millipore filter were put into sea-water containing the radioisotope as tracer. The interpretation of this still creates difficulties since, with cobalt-60, additional experiments with sediments kept in suspension showed an equally rapid binding though quantitatively to a much lower degree. At equilibrium the distribution factor, expressed as quantity of cobalt per millilitre of sediment divided by quantity of cobalt per millilitre of sea-water, was about 106 for the sediment kept still in a thin layer while in suspension the factor was lower than 700. This result is very remarkable because the highest value agrees with the distribution of the stable cobalt between sea-water and this sediment, although it would be expected that conditions for complete sorption would be better for a sediment kept in suspension. Some bacteriological phenomena were investigated in the course of these experiments but were not found to exert any influence. No differences in the composition of the sediment were observed so far. However, it is worthwhile to investigate this remarkable phenomenon TABLE I. RADIOISOTOPES CONSIDERED IN SEDIMENT STUDIES

Abundance of stable element Found distribution factor with Mediterranean in sea water Forms in sea water Reactivity with sediments Isotope sediment (thin layer technique)a (mg/1)

sorbed. possibly by 8-13 Sr: ~ 10 Sr-90 soluble carbonates and clay 3X10-4 Y: > 103 Y-90 minerals

sorbed by ion 4 5X10" 5 Cs-137 soluble exchange of clay 4.6 X10 3 XlO"2 Ba-137 m minerals

depends of form; partly soluble Rll-106 sorbed and (4- 7) x 10 4 partly particulate Rh-106 coprecipitated

particulate, sorbed and hydrolysed to (5-7)X 105 Pm-147 coprecipitated hydroxide

6 particulate, Ce-144 5.2 XlO' sorbed and s hydrolysed to (5-8) X 10 2.6X10'6 coprecipitated Pr-144 hydroxide

soluble Mn++, sorbed and s Mn-54 2 X 10"s particulate 10 coprecipitated as Mn02

particulate, Zr-95 hydrolysed to coprecipitated (1-6)X10S 10'5 Nb-95 hydroxide

s Co-60 2-5 XlO"5 soluble sorbed (3-6) X 10

Zn-65 1-2 X10"* soluble sorbed (1-4) X104

particulate, s Fe-59 1-2 Xl0" hydrolysed to coprecipitated (0.3-2) X104 hydroxide

a Ratio given is for activity/ml sediment divided by activity/ml solution. MONACO 109 further, for the other types of sediments and radionuclides as well. This phenomenon may be of importance under natural conditions because wave action and tidal currents can bring sediments into suspension and these sediments may react differently to the sediments lying still on the bottom. It was further observed that after settling to a thin layer, the sediment did not accumulate more cobalt even over a period of weeks, although there is a loss of cobalt from the untouched thin layer sediment if this is brought in to suspension. Some distribution factors determined by the thin-layer technique are shown in Table I. The values range between 10 to 106, which represents all types of binding of the elements by the sediment, including coprecipitation, which is not really a binding. The latter occurs for certain elements, such as zirconium and iron, and can be distinguished by the thin-layer technique.

2. 2. 2. Penetration into the sea bottom

As was explained in previous annual reports, an estimation of migration of the isotopes in the sea bottom can be made with the help of determined distribution factors. Roughly it can be said that the coefficients of diffusion for the radionuclides are of the order of 0. 4 X 10"8 to 0. 4 X 10_u cm2/sec, found by dividing the coefficient of diffusion of chloride (0.4 X 10~5 cm2/sec) by the distribution factors of the elements. The principles of diffusion of the free ions in the interstitial water were investigated with chloride either as tracer or as stable element. It was found that physical effects between sediment particles and interstitial water lead to delayed ion migration. This is because the charged ions are immobilized by the electric double layer on the surfaces of the particles. This effect is more important with fine sediments, at least when the electric double layer is equally present, and results in a decrease in the diffusion coefficient of less than one order of magnitude. The properties of the interstitial water itself are not affected by the electric double layer. Viscosities remain the same, which indicate that the interstitial water is a constant medium in considering the diffusion of dissolved ions.

2.2.3. Conclusions

A reasonable step was made towards solving problems on the kinetic processes of sorption of radioisotopes on sea sediments. Diffusion into the bottom is very dependent on the binding effects of the particles, these being mainly chemical processes. The study with the isotopes shown in Table I will be extended for the ocean sediments obtained from the other locations shown in Fig. 5. The fact that these sediments have already been chemically and geo- logically investigated during 1967 will facilitate the interpretation of the forthcoming results. 110 II. RESEARCH

2.3. Radiobiology of marine organisms

The radiobiological investigations concentrated on the problem of bioaccumulation of radionuclides, particularly 65Zn, by some representative members of the main groups of marine animals. On the assumption that the uptake of radionuclides follow the same rules as the uptake of particular elements of the same physico-chemical form, the influence of the abundance of each element and its physico- chemical forms was studied. 2. 3. 1. The role of Euphausiids in transport of radionuclides

The investigations on the possible role of Euphausiids in the vertical biological transport of radionuclides in the sea (see footnote 1) were continued in laboratory experiments, where the uptake, accumulation and loss of 65Zn by Meganyctiphanes norwegica M. Sars. (Euphausiids) were followed. In short term experiments it was found that the uptake of 65Zn is relatively rapid, resulting in high concentration ratios (65Zn/gram of animal divided by 65Zn/millilitre of sea-water). The values were 30 after 12 hours, 45 after 24 hours, and 60 after 48 hours, but it seems that these figures are far from the equilibrium values. Assuming that the total zinc content of Meganyctiphanes is exchangeable with that in their environment, one might expect a concentration ratio of about 2000 at exchange equilibrium. The uptake of 65 Zn by dead animals was much slower indicating that the surface adsorption of 65Zn might be only partly responsible for its accumulation by Meganyctiphanes. The loss of 65Zn by Meganyctiphanes kept in running sea water was initially rapid. About 18% of the total activity was lost within the first 5 hours. It then showed considerably, about 0. 4% per hour during the following 40 hours. The available data are at present insufficient to make a quantitative evaluation, but the relatively rapid uptake of 65Zn by Meganyctiphanes and the only partial release over a few hours, might provide a reasonable mechanism for vertical biological transport of 65Zn during the diurnal vertical migration of these animals.

2. 3. 2. Bioaccumulation of 65Zn in relation to its abundance and physico-chemical form The differences sometimes found in the investigation of the bioaccumulation of 65Zn were difficult to ascribe to the inherent errors of the methods used. It was, therefore, assumed that they originate partly from physiological differences between animals in the experiment and partly from the different relative abundance of other sea water constituents and their physico-chemical form. Experiments carried out to verify the latter assumption showed that for a relatively wide range of zinc concentration (10 to 3000 yg/l) the accumulation of 65Zn in a variety of animals (Tapes decussatus L. , Pachygrapsus marmoratus Fabr. , Meganyctiphanes norwegica M. Sars. ), is directly proportional to its concentration in the water of the experimental basins. It was then possible to predict the rate of zinc accumulation, if zinc was the only variable and if its concentration is known. ' MONACO 111

FIG. 6. Uptake of 65 Zn by whole Tapes decussatus in normal sea water and sea water enriched with Fe3+(10-« M/litre). ~~

The accumulation of zinc is much more complex when the concentrar tions of some of the other ions in the experimental basins are changed. Calcium (10~2M Ca2+ added per litre) depresses the uptake of 65Zn by about 30%, while increased iron concentrations always lead to a higher accumulation of zinc, especially well pronounced in filter feeder Tapes (Fig. 6). Even relatively small increases in iron concentration (10-6M Fe3+ added per litre) enhance the zinc uptake and since in coastal waters such an increase is quite feasible, the mechanism of. this enhancement was further investigated. It was found that in bacteria-free filtered normal sea water, about 95% of the total iron takes the form of particles larger than 5 /jm. Under the same conditions, less than 1% of the zinc is in particulate form. At increased iron concentrations (up to 10-4M Fe3+/l) the percentage of iron in particulate form remains at the 95% level, but the adsorption of zinc on these particles is considerably increased (Fig. 7). Without speaking about the physiological consequences of the increased iron concentration, the increased "particulate" zinc explains the higher rate of 6sZn accumulation from sea water with elevated iron contents. 112 II. RESEARCH

The experiments described show clearly that no practical assessment on hazards arising from contamination of seas and oceans can be made without a complex study if wrong predictions based on oversimplifications are to be avoided. III. ADMINISTRATIVE MATTERS

1. SITE, FACILITIES AND EQUIPMENT

During 1967 one of the laboratory rooms was thermoinsulated and equipped with germicidal ultraviolet illumination for work requiring sterility and constant temperature. At the end of the reporting year, three new rooms have been made available to the Laboratory by the Musee Oceanographique. The Laboratory will then have 17 rooms (220 m2) at its disposal. The limited budget of the Laboratory has made it impossible to renew or complete the existing equipment during the period under review.

2. FINANCE

The budget

For the financial period 1 January to 31 December 1967 the Monaco Laboratory had at its disposal US $149 141. Of this sum $101 869 were provided from the Agency's regular budget; the Principality of Monaco provided a contribution of $44 898 and $2374 were carried forward as unliquidated obligations from previous years.

Expenditure

The expenditure and obligations during 1967 for the project were as follows: US $ Salaries and other staff costs 131 130 Library acquisitions 320 Scientific services, supplies and equipment 11 470 Duty travel 2 420 General services and supplies 3 800

TOTAL 149 140

3. PROFESSIONAL STAFF OF THE LABORATORY

JOSEPH, Joachim (Federal Republic of Germany)

Born 1910; University of Leipzig; M.Sc. (Mathematics, physics, geophysics), Dr. rer. nat. (Oceanography).

Regierungsdirektor and former Head of the Oceanographical Department of the German Hydrographic Institute, Hamburg.

Director, responsible fot the scientific programme, the administration, and external relations with governmental and scientific agencies in matters related to the fields of activity of the Laboratory.

113 114 III. ADMINISTRATIVE MATTERS

DUURSMA, Egbert Klaas(The Netherlands)

Born 1929; Free University, Amsterdam (Chemistry, psychology), Ph.D. (Oceanography).

1956-1965 chemical oceanographer, Netherlands Institute for Sea Research, Den Helder.

Marine radiochemist conducting research of fundamental nature on the chemical and physico-chemical uptake and accumulation of radioisotopes in marine sediments.

FUKAI, Rinnosuke (Japan)

Born 1925; University of Tokio; Ph.D. (Chemistry).

Former Section Chief of Chemical Oceanography and former Chief of the Radioisotope Laboratory, National Fisheries Laboratory, Ministry of Agriculture and Forestry, Japan.

Marine radiochemist, responsible for the radiochemical aspects of the problems of the Laboratory, including chemical analysis of sea-water and of marine organisms.

KECKES, Stjepan (Yugoslavia)

Born 1932; University of Zagreb; Ph.D. (Biology).

Former Head of the Laboratory of Marine Radiobiology, "Ruder Boskovic" Institute, Rovinj, Yugoslavia.

Marine radiobiologist, conducting research on general problems of biological transport of radionuclides.

4. PUBLICATIONS BY STAFF MEMBERS

DUURSMA, E.K., HOEDE, C., Theoretical, experimental and field studies concerning molecular diffusion of radioisotopes in sediments and suspended solid particles in the sea. Part. A: Theories and mathematical calculations, Neth. J. Sea Res. Ill (1967) 423-57.

DUURSMA, E.K., A simple, horizontally-hauled large-volume water sampling-bottle of Van Dorn type, Deep Sea Res. 14 (1967) 133-34.

FUKAI, R., Valency state of chromium in seawater, Nature, London 213 5097 (1967) 901.

FUKAI, R., Some biogeochemical considerations on the radioactive contamination of marine biota and environ- ments, Proc. of lst Intern. Congr. Rad. Protect., Pergamon Press, Ltd., New York-Oxford (1967) 383-86.

KANE, J., Organic aggregates in surface waters of the Ligurian Sea, Limnol. Oceanogr. 12 (1967) 287-94.

KE£KE5, S., PuiAR, Z., MARAZOVld, Lj., Accumulation of electrodialytically separated physico- chemical forms of I06Ru by mussels, Int. J. Oceanology Limnology (1968, in press). THE INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS, TRIESTE

I. ASSISTANCE TO DEVELOPING COUNTRIES1

1. ASSOCIATE MEMBERSHIPS

Within the framework of the Associate Membership System grants have been given to three physicists, H. Harari (Israel), A.Y. Abdul-Magd (UAR) and A. N. Mitra (India), in addition to the nine previously awarded2. The Ford Foundation grant has enabled the Centre to increase the number of its Associate Members by another ten. It is expected that during its meeting in January 1968, the Scientific Council of the Centre will select the new Associates to be recommended to the Director General of the IAEA for appointment.

2. FELLOWSHIPS AND OTHER POSITIONS

A total of twenty-six fellowships, including six from UNESCO, were awarded in 1966-1967. Nineteen of these fellowships were assigned to young physicists from the following thirteen developing countries: Argentina, Brazil, Bulgaria, Greece, India (4), Nigeria, Pakistan, Poland, Romania, Taiwan, UAR, Uruguay and Yugoslavia. The fellows have been integrated in research groups and were given the possibility of attending the courses of the Advanced School of Physics (see section 3). They have published a total of 40 scientific papers3. Twenty-nine visiting scientist positions have been offered to senior physicists from the following 18 developing countries: Argentina, Brazil, Bulgaria, Ghana, Guayana, Greece, Hungary (3), India (5), Israel, Lebanon (2), Mexico, Nigeria, Pakistan (4), Poland, Romania, Syrian Arab Republic, UAR and Yugoslavia (2). They published a total of 31 scientific papers3.

3. THE ADVANCED SCHOOL OF (THEORETICAL) PHYSICS

The Advanced School of (Theoretical) Physics2 enrolled twenty-two (out of 26) fellows (seventeen of these from developing countries). The programme of courses for the academic year 1966-1967 is given in Table I.

4. LONG-TERM SEMINARS AND COURSES

A course on Theoretical Nuclear Physics has been held from 3 October to 16 December 1966, under the leadership of A. de-Shalit (Israel) and C. Villi (Italy). The main courses are listed in Table II below.

' For the purpose of this report, countries receiving technical assistance under the Enlarged Programme for Technical Assistance (EPTA) are considered as developing countries. 2 IAEA Laboratory Activities, Fourth Report, Technical Reports Series No. 77, IAEA Vienna (1967) 116. 3 See II. 11. References.

117 118 I. ASSISTANCE TO DEVELOPING COUNTRIES

TABLE I. PROGRAMME OF COURSES AT THE ADVANCED SCHOOL OF PHYSICS

Item No. Title of Course Name of lecturers)

1 Current algebra and applications D. Amati, G. Furlan

2 Elementary Particle Physics D. Amati, W. Alles

3 Field Theory I and II G. C. Ghirardi, G. Furlan

4 Microscopic theories of nuclear J. Sawicki, A. Rimini structure

5 Nuclear and elementary particle physics G. Calucci, E. Zavattini (phenomenology)

6 S-matrix theory L. Fonda

7 Theoretical astrophysics M. Hock, N. Dallaporta

8 Hypernuclei physics Shamsher Ali

9 Experimental techniques of nuclear C. Cerniogoi, G. Poiani physics

10 Neutron and reactor physics G. Pauli

Out of a total of one hundred and three participants, thirty-one came from eleven developing countries: Argentina (2), Bulgaria, Brazil, Czechoslovakia (3), Greece (2), Hungary, India (3), Pakistan (7), Poland, Romania (3), Yugoslavia (7). Most of them have been given either a 3-month fellowship, from UNESCO or financial support from the Centre. A list of lecturers and seminar lecturers is shown in Annex A.

5. FEDERATED INSTITUTES

The Centre has now eight Federated Institutes (Table III), six of which are in developing countries (Hungary, Poland, Romania and Yugoslavia). This new scheme is being extended to other developing countries (Albania, Argentina, Brazil, Chile, Greece, India, Israel, Lebanon, Lybia, Morocco, Pakistan, Syrian Arab Republic, Tunisia, Turkey, United Arab Republic) and also to Spain. Fourteen physicists from Federated Institutes from developing countries visited the Centre during 1966-1967, five from Yugoslavia, seven from Poland, and two from Hungary.

6. DISSEMINATION OF SCIENTIFIC INFORMATION

All the.preprints issued by the Centre are sent to one hundred and twelve institutes in thirty-six developing countries. A preprint register (with an abstract and classified according to the subject) of preprints on theoretical elementary particle physics received at the Centre from TRIESTE 119

TABLE II. LONG-TERM SEMINAR ON THEORETICAL NUCLEAR PHYSICS

Course No. Title of Course Lecturer

Collision theory F. Villars (MIT, USA)

Nuclear reactions G. S. Mani(Manchester, UK)

Phenomenological description of nuclear W.E. Frahn (Cape Town, scattering and direct interactions Union of South Africa)

Phenomenological collective models D.I, Rowe(Rochester, USA)

S-matrix theory of nuclear resonance J. Humblet(Lifege, reactions Belgium)

Group theory and nuclear structure M. Moshinsky (Mexico)

Microscopic theory of collective motion D. ]. Rowe (Rochester, USA)

Applications of resonance scattering theory R.H. LemmerfMIT, of nuclear physics USA)

Resonance reactions and analyticity of K. W. McVoy(Wisconsin, the S-matrix USA)

Hartree-Fock theory of equilibrium in G. Ripka (Saclay, light nuclei France)

Fundamental methods in neutron E. R. Rae (Harwell, UK) spectroscopy

12 Theoretical interpretation of neutron J. E. Lynn (Harwell, spectroscopic data UK)

13 Isobaric analogue states G. M. Temmer (Rutgers, USA) 120 I. ASSISTANCE TO DEVELOPING COUNTRIES

TABLE III. THE FEDERATED INSTITUTES (WITH THEIR CREDIT IN DAYS/YEAR) ARE AT PRESENT:

The Czechoslovak Academy of Sciences, Prague, Czechoslovakia 40

The "Josef Stefan" Nuclear Institute, Ljubljana, Yugoslavia 30

The "Ruder Boskovifi" Institute Zagreb, Yugoslavia 40

The Institute for Theoretical Physics of the University of Warsaw, Poland 30

The Institute for Nuclear Research, Warsaw, Poland 30

The Institute for Theoretical Physics of the University of Graz, Austria 30

The Hungarian Academy of Sciences Budapest, Hungary 30

The Romanian Atomic Energy Commission, Bucharest, Romania 40

other research groups is published fortnightly and sent to all addresses on the mailing list. The purpose of this register is to make physicists working in isolated centres aware of current work in theoretical physics. II. RESEARCH ACTIVITIES

1. NUCLEAR PHYSICS

In microscopic nuclear spectroscopy, research has continued on the application of the techniques of the quasi-particle higher random phase approximation and higher quasi-particle Tamm-Dancoff approximations to the study of the spectra of "superconductor" nuclei and of their electromagnetic properties. The microscopic four quasi-particle models generalized to the case of both the neutron and the proton sub- shells unfilled have been applied to such "vibrational" spherical nuclei as cadmium and the even isotopes of germanium. Eigenvectors of the quasi-particle second Tamm-Dancoff approximation have been applied to the study of the excitation of even parity states of even tin and nickel isotopes by inelastic scattering of electrons. Reaction matrices of nucleon-nucleon potentials explaining the nucleon-nucleon scattering data up to approximately 300 MeV have been constructed in separable form. Problems related to photonuclear reactions have also been investigated. To investigate the role of excited core configurations in the shell model configuration mixing due to such realistic potentials, results of three parallel methods to include such effects have been compared for the case of the even-parity states of even tin isotopes. The realistic potentials employed are those due to Tabakin. Hypernuclear problems with special reference to the scattering data, A-binding and A-A-binding in nuclear matter have been investigated. j3-transitions and other problems in the theory of (3-decay in deformed nuclei and in the Nilsson model have also been studied.

2. FIELD THEORY

The main part of the research work done in field theory covered model field theories [13, 18, 30, 53, 54, 68], In particular, two-dimensional models have been considered in order to study problems like current definition and gauge invariance. Thereby it has been shown [53, 54] that exact solutions of non-trivial theories are highly desirable in order to check the usual assumptions of field theory which are, for example, used in current algebra. An example of non-trivial model electrodynamics has also been given [68],

Two investigations [31, 108] have been concerned with special representations of the Dirac Hamiltonian and their possible applications. Increasing evidence of particles of spin < 1 has led to the development of a Stueckelberg formalism for Rarita-Schwinger fields with spin 3/2 [46], Difficulties in the use of phenomenological Lagrangians with chiral symmetries have been pointed out in another paper [105],

121 122 II. RESEARCH

3. INFINITE-COMPONENT FIELD THEORIES

The last year has seen a renewed interest in the infinite-component field theories of Majorana. One group of reports concerns itself with general features of these theories and in particular with the connection between spin and statistics. Another group concentrates on the phenomenological utility of the new ideas. The analytic structure of a scattering amplitude in the neighbourhood of vanishing momentum transfer has been studied; a programme for generalizing the Regge pole hypothesis in the presence of internal symmetries has been outlined, and actual calculations have been started on a semi-empirical theory in which scattering amplitudes are related to generalized Feynman diagrams [136], A positive advance has been the realization that infinite multiplets can account for states in the two-particle continuum, rather than just idealized isobars.

4. BOUND STATES AND QUARK MODEL

Various questions, connected with the quark model and, more generally, with the bound state problem, have been investigated by several theoreticians in the Centre. Two directions can be distinguished. The first is the phenomenological approach in whose framework, after making assumptions about the forces acting between quarks, the statistics, etc., many relations have been derived among hadron masses, coupling constants, decay rates, etc. [27, 63]. The second direction is nearer to field theory and is an attempt to formulate a quantitative theory of the bound states in the semi-relativistic and relativistic case. Doing this, the authors of Refs [40, 113] have preferred the one-time formalism in the two-body problem, in contrast with the two-time formalism used in the Bethe-Salpeter equation.

5. N/D METHOD

The existence of the N/D representation has been proved by Warnock [22] for the case of a finite number of two-body channels. This existence theorem requires asymptotic conditions which are compatible with the Regge pole model only if absorption is also taken into account through the introduction of suitable parameters. A review of the N/D method has been given by Warnock [104] covering for spinless equal-mass particles physical values of the angular momenta in the direct channel. The existence of an essential singularity in the N-function at i = - 1 (accumulation point of Regge poles) has been established by Joshi and Ramachandran [106], On introducing moving cuts from the integral equation for the N-function one gets conditions on the discontinuity across the cuts in order to eliminate the essential singularity. An application of the Faddeev method to re-arrangement collisions has been made by Abul-Magd [42], The transition amplitude has been calculated by iteration of the Faddeev coupled equations. TRIESTE 123

6. SCATTERING REGGE POLES

A number of papers [51, 74, 109, 122, 123] are devoted to the expansion of scattering amplitudes in terms of sets of functions drawn from the unitary representations of the homogeneous Lorentz group. The purpose of this is to create a new type of partial wave analysis which generalizes the work of Toller in being applicable to inelastic and off- forward processes, while tending smoothly to the Toller form where that is applicable. In consequence the t = 0 singularity problems which had appeared in the standard Regge analyses are removed and, in addition, the phenomenon of daughter poles is accomodated naturally. The general structure of such expansions including discussions of the orthogonality and completeness of the expansion functions and of the rather elaborate kinematical manipulations which are needed are given in [51] and [74]. Applications of the method are made to the processes of 7rN charge-exchange scattering in [109], to 17-production in [122] and to p -production in [123]. The problem of "reggeizing" higher symmetry models is examined in [81] and [128], The particular case of inhomogeneous 0(6, 1) is dealt with in [81] where it is found, firstly, that reggeization of ordinary spin' gives rise to recurrences also in iso-spin and, secondly, that generalized Regge recurrences can be arranged in sequences which are in one-one correspondence to rungs of appropriate non-compact towers. Similar considerations are applied in [128] to other models including inhomogeneous U(12). For these cases, however, due to the inherent complexity of the models, it has not been possible to reach such definite conclusions.

7. GROUP THEORY

The work done in group theory dealt mainly with problems in the representation theory of'non-compact groups. The work falls into three broad categories: (a) general theory, (b) U(p, q) and 0(p, q) groups, and (c) tables. In the general theory group, one of the papers [94] gives a formulation of the theory of induced representations of finite groups in the language of modules, and another [15] uses the techniques of generalized tensors to solve some problems connected with the supplementary series of unitary representations of non-compact semi-simple groups. In the U(p, q) sections, some (restrictive) conditions under which ladder representations of U(p, q) may yield U(p, q)-invariant meson-baryon vertices is deduced [35], Work on the conformal group SO(4, 2) has also been done, i. e. unitary representations in the Hilbert space of harmonic functions [24], The unitary representations of the extension of the Poincare group by "dilatations" are studied and orbits corresponding to the time-like hyperbolas and to the apex of the. light cone are derived [28], In this section may also be included lectures [85] on the "operator calculus of patterns", which is generalization to the n-dimensional unitary group of the Wigner-Racah angular momentum calculus. Simple expressions for the transformation matrices between 0(3) and 0(2, 1) bases in unitary irreducible representations of SL(2, C) have been derived [112], The section of "tables" consists of some detailed work on the Clebsch-Gordan coefficients of the Lorentz group [96] and 124 II. RESEARCH of the tables for the Clebsch- Gordan series of some of the simple classical groups [25],

8. SYMMETRIES

Weaker alternatives to U(12) particle symmetry have been considered. The complete separation of strange and non-strange particles leads to U(8) symmetry. This symmetry has been applied to four-particle vertices, in particular the (PP-» 2 mesons) annihilation. While this approach does not avoid all the difficulties of 0(12), it appears to be a better approximation for four-particle vertices. As an alternative to theU(12) generalization of the Bargmann-Wigner spinor equations, the Weinberg spinor equations have been generalized to SL(6, C). This approach leads to meson and baryon fields with fewer components and to unique SL(6, C) invariant, three-particle vertices. This serves to illustrate that alternatives to the 0(12) formalism, while equivalent for free fields, give different results for interactions. Schwinger's postulate of U(4) as a partial symmetry, developed as an alternative to current algebra, is extended to U(6). An effective, numerical, U(6)-invariant Lagrangian is postulated and the Lorentz extension made. The treatment of the couplings of tensor, axial, and scalar mesons to vectors and pseudoscalars is in good agreement with experiment. The near equality of the coupling constant and the "universal" pirir coupling suggests parallel Regge trajectories for 1" and 2+ mesons and perhaps indicates the working of a larger universality principle. The assignment of physical particles to multiplets of symmetry groups is being examined. The success of the (3, 3*) multiplet of SW3 in reproducing the mass spectrum of the O", 1", and 2+ nonets suggests that larger multiplets be considered, in particular the (6, 6*) of SW3 which reduces to 1 © 8 Q)21 under SU(3). On the basis of the mass spectrum, it is unlikely that the 0" mesons can be accomodated in a (6, 6*), but the lack of data makes the situation for the 1" and 2+ mesons indefinite. The possibility that the 3/2" baryon resonances may be members of a 27 of SU(3) is examined. The widths of these particles indicate that they are not members of octets or decuplets. The Yq (1700), Y* (1715), and S ' (1820) may be put into the 27, but the other members of the multiplet, as predicted by the Gell-Mann-Okubo mass formula, have not been observed. Resonances in this multiplet will not be just orbital excitations of the three-quark baryon state but will be higher representations involving more than three quarks.

9. DYNAMICAL PROBLEMS

A number of papers have been devoted to the study of the algebraic formulation of dynamical problems in classical quantum mechanics [59], Through the introduction of the Fock variables and their canonical con- jugates a complete and simple geometrization of the Kepler problem in a four-dimensional space was achieved [89], Still in the domain of the non-relativistic two-body system, a systematic search for potentials which allow a higher dynamical symmetry was performed [32], A TRIESTE 125 formulation of the dynamical problem through the Casimir operator of the non-compact spectral algebra was extended to infinite-component relativistic equations of the Majorana type [45], To this trend of thought a paper on a generalization of the static strong coupling with the inclusion of multi-meson sources in place of the conventional p-wave source also belongs.

10. SUPERCONVERGENCE AND CURRENT ALGEBRA

The activity at the Centre in these rapidly developing fields has been quite intensive. Direct numerical tests of superconvergence relations have been made for a fixed value of the momentum transfer and a finite set of resonances in pion photoproduction [27 ], vector meson-nucleon scattering, baryon- antibaryon scattering, etc. On a more fundamental level, the possibility of superconvergent behaviour of strong interaction amplitudes being the origin of the observed symmetries was investigated [23] as well as the structure of the complex J-plane [62, 120], The saturation of superconvergence relations for a range of the momentum transfer by an infinite set of one-particle states was put into doubt by the observation that, in an equivalent problem, the Born approximation in infinite-component field theories, crossing properties in their usual form were violated [88], The formulation of current algebra found some slight amelioration in a set of covariance conditions on the sum rules [55]; a model-dependent formulation of on-mass-shell current algebra was given [91] and a tentative hadronic mass spectrum was calculated based on the assumption that a saturation with an infinite set of one-particle states is possible [76], The problem of possible subtraction terms in the sum rules was taken up [120]; in a model of spinless particles non-Regge terms were found to be due to the lack of unitarity. Also in [79] this problem was attacked in a more phenomenological contest in nucleon Compton scattering.

11. REFERENCES *

Publications and pre-prints issued in the reporting period

[1] BOSE, S. K. , SU(3) 8 SU(3) symmetry and possible existence of a boson 27-plet, Nuovo Cimento (Letters) 46A (1966)419.

[2] 1C/66/104 a MADUEMEZIA, A., Matrix elements for irreducible representations of the U(6, 6) algebra in harmonic function space, ]. Math. Phys. (in press).

[3] IC/66/105 HUMBLET, J., LEJEUNE, A., On the relation between total and partial widths in nuclear reactions, Phys. Letters 23 10 (1966) 561.

* After the reference number is given the Centres report number, preceding the reference proper. a IAEA Fellow, a Visiting Scientist since 18 July 1967. 126 II. RESEARCH

[4] Int. Rep. JANOUCH, F. , VINDUSKA, M. , Beta decay. 15/1966

[5] IC/66/106 HUMBLET, J., LEBON, G., Perturbation of resonance states and energy shift in mirror nuclei, Nucl. Phys. A96 (1967)593.

[6] IC/66/107 bNWACHUKU, C. O. , Broken 0(8) and PF annihilation at rest, Phys. Rev. 157 (1967)1490.

[7] IC/66/108 IOSIFESCU, M., STANCU, F., SUs Wigner coefficients in angular momentum space, Nucl. Phys. B1 (1967)471.

[8] IC/66/109 PISENT, G., ZARDI, F., Intermediate resonances of neutrons scattered by deformed nuclei.

[9] IC/66/110 de-Shalit, A., Recent developments in theoretical nuclear physics.

[10] IC/66/111 bBOGDAN, D., LIPNIK, P., Nuclear matrix elements of first forbidden beta transitions in the Nilsson model, Nuovo Cimento 5IB (1967)376.

b 6 til] IC/66/112 SHAMSHER ALI, BODMER, A. R., The M-hypernucleus MHe , Nuovo Cimento 50 (1967)511.

[12] IC/66/113 aMADUEMEZIA, A., On discrete degenerate representations of the conformal group in space-time, Nuovo Cimento 51A (1967)320.

[13] IC/66/114 bHABERLER, P. L. F., Relation between bare and physical mass of vector bosons in a two-dimensional field theory, Nuovo Cimento (Letters) 47 (1967)929.

[14] IC/66/115 DELBOURGO, R., ABDUS SALAM, STRATHDEE, J., Stress tensor and the 2+ mesons, Nuovo Cimento 49 (1967)593.

[15] IC/66/116 SOLOVIEV, V. G., b BOGDAN, D., SALAGEANU, S., DECIU, N., Absolute ft values for first forbidden fl-transitions to the collective, non-rotational states of the type JirK = 2 + 2, Nuovo Cimento 51B (1967)66.

[16] IC/66/117 JANOUCH, F. , Time reversal invariance and correlation theta-gamma circular polarization.

[17] IC/66/118 bBOGDAN, D., LIPNIK, P. , First forbidden beta transitions between K-mixed states, Nuovo Cimento (in press).

[18] IC/66/119 bHABERLER, P. L. F., Consistency problems in an extended Schwinger-Thirring-Wess model, Acta Phys. Austr. (in press).

[19] IC/66/120 FRAHN, W. E, , Relation between proton-nucleus and proton-nucleon interaction at 20 GeV, Phys. Letters 24B (1967)216.

[20] IC/66/121 c NAQVI, J. H. , Separable non-local two-nucleon potential for odd-parity spin triplet states, Nucl. Phys. (in press).

[21] IC/67/1 Withdrawn.

[22] IC/67/2 WARNOCK, R. , Existence of many-channel N/D representation, Nuovo Cimento 50 (1967)894.

[23] IC/67/3 PANDE, L. K. , Saturation, static SU(2)-model and dynamical symmetries, Phys. Letters 24B (1967)243.

[24] IC/67/4 aMADUEMEZIA, A., On the conformal group algebra and its unitary representation in the space of harmonic functions, Nuovo Cimento 51A (1967)932.

[25] Int. Rep. PAJAS, P., Tables of the Clebsch-Gordan series for Lie groups A2, B2, G2, As, Bs 1/1967 and C„.

a IAEA Fellow, a Visiting Scientist since 18 July 1967. b IAEA Fellow. c UNESCO Fellow. TRIESTE 127

[26] IC/67/5 OTTAVIANI, P. L., SAVOIA, M., SAWICKI, J., Comparison between the two- and four-quasiparticle Tamm-Dancoff approximations for even parity states of even tin isotopes calculated with finite range forces, Phys. Letters 24B (1967)353.

[27] IC/67/6 PANDE, L. K., Superconvergence in pion photoproduction, Nuovo Cimento (Letters) 48 (1967)839.

[28] IC/67/7 INGRAHAM, R. L., The unitary representations of the similitude group of space- time.

[29] ICTP Publ. bBHASIN, V.S., A note on the high-energy deuteron scattering from Fadeev's No. 1/1967 three-particle formulation, Nuovo Cimento (Letters) 49 (1967) 736.

[30] ICTP Publ. bHABERLER, P. L. F., dSAAVEDRA, I., Composite particles in a two-dimensional No. 2/1967 field theory, Nuovo Cimento (Letters) 49 (1967) 194,

[31] ICTP Publ. SAAVEDRA, I., Equivalent representations of the Dirac equation, Nucl. Phys, No.3/1967 B1(1967)690.

[32] IC/67/8 MAKAROV, A. A., SMORODINSKY, J. A., VALIEV, Kh., WINTERNITZ, P.. A systematic search for non-relativistic systems with dynamical symmetries. Part I - The integrals of motion, Nuovo Cimento (in press).

[33] Int. Rep. CASTELL, L., Linear field equations for particles with arbitrary spin, Nuovo 2/1967 Cimento 50 (1967)945.

[34] IC/67/9 BOYCE, J. F., DELBOURGO, R., ABDUS SALAM, STRATHDEE, I. , Partial wave analysis — Part I.

[35] IC/67/10 ANDERSON, R. L., R^CZKA, R., Coupling problem for U(p, q) ladder representations • II. Limitations on the coupling of U(p,q) ladders, Proc. Roy. Soc. (in press).

[36] IC/67/11 BOLLINI, C.G., dGIAMBIAGI, J.J., Sum rules and the electromagnetic isobar-nucleon current, Nuovo Cimento (Letters)(in press).

[37] IC/67/12 BOFFI, S., PACATI, F. D., SAWICKI, J., Direct photonucleons from odd nuclei and coupling of single nucleons to collective core excitations. Reaction %e(y,n)8Be - II, Nuovo Cimento (in press).

[38] ICTP Publ. b DELLA SELVA, A., De RUJULA, A. , bMATEEV, M., Neutral decays into No. 5/1967 wOyy, Phys. Letters 248(1967)468.

[39] IC/67/13 aMADUEMEZIA, A., Localized states and group contraction in 4 + 2 de Sitter space, Nuovo Cimento 51A (1967)585.

[40] ICTP Publ. DESIMIROV, G., bMATEEV, M., On some properties of the quasi-potential for No. 6/1967 interacting spinor fields, Nucl. Phys. B2 (1967)218.

[41] IC/67/14 e GRYPEOS, M. E. , On the re-arrangement energy of the nuclear many-body problem, Nuovo Cimento 51B (1967)347.

[42] IC/67/15 f ABUL-MAGD, A. Y. , Note on the three-body treatment for re-arrangement collisions, Nuovo Cimento (in press).

[43] IC/67/16 bSHAMSHER ALI, e GRYPEOS, M. E., KOK, L. P., A-p scattering and the A-N interaction, Phys. Letters 24B (1967)543.

[44] IC/67/17 WADA, W. W., Partially conserved tensor current hypothesis and the photopion amplitude.

[45] IC/67/18 BUDINI, P., Algebraic formulation of dynamical problems (Schladming Lectures), Acta Phys. Austr. Suppl. IV (1967) 118.

a IAEA Fellow, a Visiting Scientist since 18 July 1967. b IAEA Fellow. d Associate Member. e IAEA Fellow, a visiting scientist from 18 July until 30 Sept 1967. ' IAEA Fellow, appointed an Associate Member from 1 January 1968. 128 II. RESEARCH

[46] ICTP Publ. KAMEFUCHI, S., SHIMODAIRA, H., WATANABE, H., The Stueckelberg No. 7/1967 formalism for Rarita-Schwinger field with spin 3/2, Nucl Phys. B2 (1967)360.

[47] IC/67/19 bSRIVASTAVA, P.P. , Superconvergent sum rule for pion photoproduction on A0, Nuovo Cimento (Letters) 49 (1967) 741.

[48] ICTP Publ. KORTHALS ALTES, C. P., Superconvergence in nucleon-p meson scattering, No. 8/1967 Nuovo Cimento (Letters) 49A (1967) 753.

[49] IC/67/20 bBOGDAN, D., The Woods-Saxon wave functions and the beta transitions of deformed nuclei.

[50] ICTP Publ. INGRAHAM, R. L., Spectra of generators in irreducible unitary representations No. 9/1967 of non-compact semi-simple groups, Commun. Math. Phys. £(1967)17.

[51] IC/67/21 DELBOURGO, R. , ABDUS SALAM, STRATHDEE, J., Partial wave analysis in terms of the homogeneous Lorentz group, Phys. Rev. (in press).

[52] IC/67/22 b SHAMSHER ALI, AFZAL, S.A., Phenomenological a-a potential and the ground state of Be?, Nuovo Cimento (Letters) 50 (1967)355.

[53] IC/67/23 HAGEN, C. R., New solutions of the Thirring model, Nuovo Cimento 51B (1967) 169.

[54] IC/67/24 HAGEN, C. R., Current definition and mass renormalization in a model field theory, Nuovo Cimento 51B (1967) 1033.

[55] IC/67/25 BOLLINI, C.G., GIAMBIAGI, J. J., dTIOMNO, J., On the covariance of equal time commutators and sum rules, Nuovo Cimento 51A (1967)717.

[56] IC/67/26 cGMITRO, M., Matrix elements of non-central two-body nuclear forces.

IC/67/27 bBHASIN, V. S., KATYAL, D. L., MITRA, A. N., Baryon mass splittings in an [57] SU(6) X 0(3) quark model, Phys. Rev. (In press).

ICTP Publ. aMADUEMEZIA, A., Some consequences of Segal's positive-energy particle model [58] No. 11/1967 with mass splitting.

IC/67/28 DOEBNER, H. D., MELSHEIMER, O., On limitable dynamical groups in quantum [59] mechanics - I: General theory and a spinless model.

ICTP Publ. FERREIRA, E. M. , SESMA, J., Sum rules in quantum mechanics, Nuovo Cimento [60] No. 12/1967 (in press).

IC/67/29 b SHAMSHER ALI, KOK, L. P., GRYPEOS, M. E., A note on the AA-hypernucleus [61] J^C, Nuovo Cimento 50 (1967) 373. [62] IC/67/30 b RAMACHANDRAN, R., Fermlon trajectory parametrization and superconvergence.

IC/67/31 d MITRA, A. N., b SRIVASTAVA, P. P., Quark model couplings and strong decays [63] of tensor and axial mesons, Phys. Rev. Letters (in press).

Int. Rep. GYflRGYI, G., On the symmetries of the Kepler problem. [64] 3/1967

ICTP Publ. GAVRILA, M., Analytic evaluation of the Kramers-Helsenberg matrix element [65] No. 13/1967 for elastic scattering of photons by K shell electrons.

IC/67/32 bHENDEKOVIC, I., OTTAVIANI, P. L., SAVOIA, M., SAWICKI, J., Two- and [66] four-particle Tamm-Dancoff theories of vibrational states of medium-heavy nuclei with unfilled shells of both neutrons and protons: I - General theory, Nuovo Cimento (in press).

[67] Int. Rep. INGRAHAM, R. L., Unification of PoincarS and internal symmetry groups. 4/1967

IAEA Fellow, a Visiting Scientist since 18 July 1967. IAEA Fellow. UNESCO Fellow. Associate Member. TRIESTE 129

[68] Int. Rep. DELBOURGO, R. , ABDUS SALAM, STRATHDEE, J., A convergent field theory, 5/1967 Phys. Letters 24B (1967) 622.

[69] IC/67/33 KORTHALS ALTES, C. P., bSRIVASTAVA, P.P., Superconvergence relations in ir-A scattering, Nuovo Cimento 51A (1967)533.

[70] ICTP Publ. NARAYAN, D. S., On a model of saturating a superconvergent sum rule. No. 14/1967 Nuovo Cimento (in press).

[71] ICTP Publ. GUPTA, V. , NARAYAN, D. S., Superconvergence sum rules for baryon-antibaryon No. 15/1967 scattering, Nuovo Cimento (in press).

[72] IC/67/34 WARNOCK, R. , Levinson relation for real part of the phase shift and partial waves at infinity in Regge theory.

[73] Int. Rep. aMADUEMEZIA, A., Possible scheme for uniting space-time and intrinsic symmetries. 6/1967

[74] Int. Rep. DELBOURGO, R., ABDUS SALAM, STRATHDEE, J., Harmonic analysis in terms of 7/1967 the homogeneous Lorentz group, Phys. Letters 25B (1967)230: (Also appeared as Imperial College, London, preprint.)

[75] ICTP Publ. JOSHI, G. C., PANDE, L. K., Spectral function sum rules and the decay

[76] IC/67/35 GRODSKY, L T., MARTINIS, M. ,bSWI{CKI, M., An upper bound on possible mass spectra from single-particle saturation of current algebra sum rules, Phys. Rev. Letters 19 (1967)332.

[77] ICTP Publ. DELLA SELVA, A. ,bMASPERI, L., Isobaric saturation of Adler-Weisberger sum rule. No. 17/1967 Nuovo Cimento 50 (1967) 997.

[78] IC/67/36 BLOKHINTSEV, D.I. , Macroscopic causality.

[79] IC/67/37 WADA, W. W., High-energy assumption and subtraction constants in Compton scattering sum rules, Nuovo Cimento (in press).

[80] IC/67/38 MITRA, A. N., SAXENA, R. P., Partial symmetry and meson coupling, Phys. Letters 25B (1967) 225.

[81] IC/67/39 ABDUS SALAM, STRATHDEE, J., Reggeization of internal symmetries, Phys. Rev. Letters 19 (1967)339.

[82] IC/67/40 bBHASIN, V. S. , PANDE, L. K. , Groups for static multispin meson-source models - I, Phys. Rev.- (in press).

[83] IC/67/41 PAJAS, P., Degenerate representations of the symplectic groups - II. The non- compact group Sp(p, q).

[84] ICTP Publ. bPASCUAL, R. , b SRIVASTAVA, P.P., Soft photon emission approach to the No. 18/1967 decays to, ip, p - 2Try.

[85] IC/67/42 MITRA, A. N. , Three-body investigations with realistic potentials.

[86] IC/67/43 bHENDEKOVIC, J,, A possible microscopic approach to the description of the vibrational states of spherical even-even nuclei.

[87] IC/67/44 COCHO, G., Is the scattering amplitutde analytic at u = 0?

IC/67/45 GRODSKY, I. T. , Trouble with Fubini's single-particle pole solution to super- [88] convergence relations, Phys. Letters 25B (1967) 149.

IC/67/46 GYORGYI, G., Kepler's equation, Fock variables. Bacry's generators and Dirac [89] brackets, Nuovo Cimento (in press).

IC/67/47 NARAYAN, D. S. , SAXENA, R. P., SRIVASTAVA, R.P., Chiral symmetry, super- [90] convergence and sum rules for scattering amplitudes.

a IAEA Fellow, a Visiting Scientist since 18 July 1967. b IAEA Fellow. 130 II. RESEARCH

[91] IC 767/48 BISWAS, S. N. , BOSE, S. K., DATTA, K., DHAR, J., NOVOZHILOV, Yu. V. , SAXENA, R. P., Superconvergent dispersion relations and 1=2 electromagnetic mass differences of hadrons, Phys. Rev. (in press).

[92] ICTP Publ. bBARTL, A., KORTHALS ALTES, C. P., Residues of p and R trajectories from N-N No. 19/1967 scattering.

e c [93] IC/67/49 GRYPEOS, M. E. , KOK, L. P., ALI, S., On the binding energy of a A particle in nuclear matter, Phys. Letters (in press).

[94] ICTP Publ. MOZRZYMAS, J., Induced representations and their applications to quantum No. 20/1967 mechanics.

[95] ICTP Publ. MARX, G., SURANYI, P. , Semistrong C violation with AI = 3, Nuovo Cimento No.21/1967 (in press).

[96] IC/67/50 ANDERSON, R. L. , R£CZKA, R., RASHID, M. A., WINTERNITZ, P., Clebsch- Gordan coefficients for the Lorentz group I — principal series.

[97] IC/67/51 De RUJULA, b MATEEV, M., bSwi$cki, M., Subtracted dispersion relations and on-mass-shell current algebra. Pseudoscalar meson baryon scattering lengths, Phys. Rev. (in press).

[98] IC/67/52 BIEDENHARN, L. C., Three lectures on tensor operators in U(n): An introduction to an "operator calculus of patterns".

[99] Int. Rep. BIEDENHARN, L. C. , GIOVANNINI, A., A remark on interpreting Majorana's 9/1967 equation, Nuovo Cimento (Letters) 51A (1967)870.

[100] IC/67/53 GYARMATI, B., SAWICKI, J., Two-nucleon transfer reactions with vibrational nuclei and two- and four-quasiparticle Tamm-Dancoff microscopic theories of vibrational states.

[101] Int. Rep. SAWICKI, J., Method of Bogolubov quasiparticles in nuclear microscopic spectroscopy 10/1967 (selected topics). [102] IC/67/54 PASCUAL, R. , On break-up channels in muon capture by helium-3, Nucl. Phys. (in press).

[103] Int. Rep. INGRAHAM, R. L., Frame-dependence of cross-sections. 11/1967

[104] IC/67/55 WARNOCK, R. L. , Inelastic N/D equations and Regge theory.

[105] IC/67/56 FRIED, H. M., Difficulties with non-linear (e. g. chiral) dynamics.

IC/67/57 JOSHI, C.C., b RAMACHANDRAN, R., Gribov-Pomeranchuk phenomenon in [106] N/D approach, Phys. Rev. (in press).

IC/67/58 STOYANOV, D. Tz., TODOROV, I. T., Self-coupled representations of the [107] Lorentz group and infinite-component Fermi fields.

Int. Rep. RAMAKRISHNAN, A., New perspectives on the Dirac Hamiltonian and the [108J 12/1967 Feynman propagator.

IC/67/59 d AKYEAMPONG, D. A., BOYCE, J. F., RASHID, M. A., The homogeneous Lorentz [109] group and irN charge-exchange scattering, Phys. Letters 25B (1967)336.

Int. Rep. KLEINERT, H. , Relativistic current of the H-atom in 0(4, 2) dynamics, Phys. [110] 13/1967 Rev. Letters (in press).

RYDER, L. H., Implications of the revised KJ-K2 regeneration phase for theories [111] IC/67/60 of CP violation.

d AKYEAMPONG, D. A., BOYCE, J. F., RASHID, M. A., On the transformation from [112] IC/67/61 0(3) to 0(2,1) bases in SL(2, C).

IAEA Fellow. UNESCO Fellow. Associate Member. IAEA Fellow, a visiting scientist from 18 July until 30 Sept 1967. TRIESTE 131

[113] IC/67/62 FISCHER. J., LIMIC, N.. NIEDERLE, I., R^CZKA, R., Semi-relativistic equation for quark-antiquark system, Nuovo Cimento (in press).

[114] IC/67/63 DELBOURGO, R. , RASHID, M.A., ABDUS SALAM, STRATHDEE, J., Green's functions for Regge trajectories, Phys. Letters 25B (1967)475.

[115] Int. Rep. BAGHDADI, M. S., Infinite-component field equations and PCT invariance. 14/1967 [116] Int. Rep. FRONSDAL, C., On the supplementary series of representations of semi-simple 15/1967 non-compact groups.

[117] Int. Rep. bARAGONE, C., Two examples of singular canonical formalism. 16/1967

[118] IC/67/64 ANDERSON, R. L., R£CZKA, R., RASHID, M. A., WINTERNITZ, P., Symmetry and recursion relations for the Clebsch-Gordan coefficients of the homogenous Lorentz group.

[119] ICTP Publ. ALI, S., KOK, L. P. , The ^Be interpretation of the first discovered M-hypernuclear No.22/1967 event, Nucl. Phys. (in press).

[120] Int. Rep. DELLA SELVA, A., bMASPERI, L., ODORICO, R., Indications on the p-like 17/1967 singularities in the complex J-plane, Nuovo Cimento (in press).

[121] Int. Rep. PAPINI, G., Superconductors as detectors of gravitational waves. 18/1967

[122] Int. Rep. NATH, L. M., Partial wave analysis of the reaction 7r~P-»t]n in terms of the 19/1967 homogeneous Lorentz group, Nuovo Cimento (in press).

[123] IC/67/65 RASHID, M. A. ,CSAMIULLAH, M., 0(3,1) symmetry and production at high energies: single Lorentz pole versus single Regge pole.

[124] IC/67/66 CASTELL, L. , The physical aspects of the conformal group SO0(4, 2), Nucl. Phys. (in press).

[125] IC/67/67 POLKINGHORNE, J. C., Non-Regge terms in single current amplitudes, Nucl. Phys. B3 (1967)395.

[126] ICTP Publ. FIEDELDEY, H., ERENS, G. , VAN WAGENINGEN, R. , HOMAN, D. , KOK, L. P. , No. 23/1967 Further calculations on a simple triton model.

[127] Int. Rep. ' NWACHUKU, C. O. , SU(3)27-plet structure of the Jp= 3/2" baryon resonances, 20/1967 Nuovo Cimento (Letters) 51A (1967) 1158.

[128] Int. Rep. DELBOURGO, R. , RASHID, M.A. , ABDUS SALAM, STRATHDEE, J., Reggeization 21/1967 of internal symmetries - II.

[129] Int. Rep. DESIMOROV, G. M., bMATEEV, M. D., On the quasipotential description of the 22/1967 electron-positron interaction.

[130] Int. Rep. SHAY, D. , SL(6,C) and the Weinberg formalism for spin-s particles. 23/1967

[131] Int. Rep. NWACHUKU, C. O. , c SAMIULLAH, M., SHAH, K. T., 0(3,1) symmetry and. 24/1967 w production at high energy.

[132] Int. Rep. NWACHUKU, C. O. , SAMIULLAH, M. , SHAH, K. T. , 0(3,1) symmetry and the 25/1967 contribution of a daughter trajectory to the KN charge exchange scattering.

[133] IC/67/68 KADYSHEVSKY, V. G. , MATEEV, M. D. , On a relativistic quasipotential equation in the case of particles with spin.

[134] Int. Rep. KOMY, S. R., SAMIULLAH, M. , 0(3,1) symmetry and the "weak dependence" 26/1967 of the exchanged trajectories in irN - tjN^ (1236) process.

b IAEA Fellow. c UNESCO Fellow. 132 II. RESEARCH

[135] IC/67/69 COCHO, G., FRONSDAL, C., GRODSKY, I. T., KADYSHEVSKY, V. G., Regge pole exchange in classical physics and in non-relativistic quantum mechanics.

[136] IC/67/70 FRONSDAL, C., Feynman rales for Reggeons.

[137] IC/67/71 CASTELL, L., The reduction of the most degenerate representations of SO0(p,q) with respect to SO0(p-l, q-l)(£ Tp+q-2-

[138] Int. Rep. NARAYAN, D. S. , SAXENA, R.P., b SR1VASTAVA, P. P., A new class of 27/1967 superconvergence sum rules for scattering amplitudes.

IAEA Fellow. III. THE CENTRE AS AN INTERNATIONAL FORUM FOR PERSONAL CONTACTS BETWEEN THEORETICAL PHYSICISTS FROM COUNTRIES AT ALL STAGES OF DEVELOPMENT

1. MEMBER STATES AND INTERGOVERNMENTAL ORGANIZATIONS REPRESENTED

In 1966-1967 thirty-nine Member States were represented at the Centre. Apart from the nineteen countries already mentioned (see I. 2) they are: Austria, Belgium, Canada, Ceylon, Chile, Taiwan, Federal Republic of Germany, Finland, France, Italy, Japan, the Netherlands, New Zealand, South Africa, Spain, Sweden, Switzerland, United Kingdom, USA, USSR. Three intergovernmental organisations (CERN, NORDITA, EURATOM) were also represented.

2. NUMBER OF SCIENTISTS WHO WERE AT THE CENTRE

The one hundred and fifty-two physicists who worked at the Centre as associate members, visiting scientists, guest lecturers, consultants or visitors from federated institutes are listed in Annex A. In addition there were also the lecturers shown in Annex B. Taking these scientists and the IAEA and UNESCO fellows into account, as well as the participants in the Seminar on Nuclear Physics (see II. 4) the total number of physicists who attended the Centre during 1966-1967 is three hundred and three, representing 40 countries and three intergovernmental organizations.

133 IV. ADMINISTRATIVE MATTERS

1. FINANCE

The budget

For the period 1 January to 31 December 1967 the International Centre for Theoretical Physics had at its disposal funds totalling US$537 978. Of this amount $ 278 000 represented the Italian Government's contribution for the financial year 1967, $ 150 000 were contributed by the Agency (a sum of $ 115 000 from the Regular Budget and $ 35 000 from the Operating Fund); $ 40 000 were received as a donation from the Ford Foundation, and $ 20 533 represented other income. In addition, a sum of $ 46 713 was carried forward as savings from the previous year's operation and $ 2732 were available from savings on liquidation of the previous year's obligations.

Expenditure

The expenditure and obligations during 1967 were as follows:

US$

Scientific Council 470 Salaries and other staff costs 140 488 Visiting scientists 175 603 Guest lecturers 4 666 Duty travel 7 159 Conferences and Seminars 62 404 Scientific documents 15 736 Library acquisitions 11 341 Common services, supplies and equipment 52 501 Hospitality 3 281 Fellowships 50 450 Associate members 8 976 Federated institutions 3 245 TOTAL 536 320

134 TRIESTE 135

2. STATISTICAL DIGEST

2. 1. Scientific staff

Number of physicists who worked at the Attending in the Centre capacity of Total From 20 developing countries

Visiting scientists and Associate Members 88 40 IAEA Fellows 20 16 UNESCO Fellows 6 3 Guest lecturers 28 5 Consultants 11 4 Visitors from Federated Institutes 25 22

178a 90 a The total was 83 in 1964/65 and 128 in 1965/66

2.2. Participation of scientists expressed in man/month

Total Developing countries Percentage from (man/month) (man/month) developing countries

1964/65 410 187. 5 44% 1965/66 541 202. 5 37%a 1966/67 549 325 59. 2% a The decrease for 1965/66 is due to the plasma physics group which included mainly scientists from developed countries, and for whom the respective countries accepted the financial responsibility. 136 IV. ADMINISTRATIVE MATTERS

2.3. Participation in extended Seminar courses

1964/65 1965/66 1966/67 Number of: (Plasma Physics) (High-energy (Nuclear Physics) physics)

Lecturers 12 43 32 Participants a 50 78 103

Total 62 121 135 Nationalities represented 40 37 40b a Not including the Staff of the Centre present at the time. b Plus delegates of CERN, NORDITA and EURATOM

2.4. Advanced School of Physics

Number of Fellows who attended the School Academic year Total From developing countries

1964/65 12 8 1965/66 15 10 1966/67 22 17

2.5. Library

Number of books 4700 Number of scientific periodicals 125 Preprints and reports received per month from other institutions 200

2. 6. Scientific Information

Preprints issued in 1964/65 91 Preprints issued in 1965/66 124 Preprints knd reports issued in 1966/67 141 Total 356 TRIESTE 137

Published Books

Proceedings of the Seminar on Plasma Physics (640 pages) (1965) Proceedings of the Seminar on High-Energy Physics and Elementary Particles (1000 pages) (1965) Proceedings of the International Course on Nuclear Physics (1000 pages)(1967) Proceedings on the International Course on the Theory of Condensed Matter (in preparation) (1968)

Preprint Registry

Issued fortnightly since January 1966 (100 titles with abstracts)

Mailing Lists

Nuclear Physics 300 Plasma Physics 300 High-Energy Physics 750 ANNEX A

PROFESSIONAL STAFF OF THE CENTRE, VISITING SCIENTISTS AND ASSOCIATES, GUEST LECTURERS, CONSULTANTS, FELLOWS, AND VISITORS FROM FEDERATED INSTITUTES

PROFESSIONAL STAFF OF THE CENTRE

ABDUS SALAM (Pakistan) Director P. BUDINI (Italy) Deputy Director

A. Hamende (Belgium) p. Rendi (Austria) Scientific Information and Documentation Officer Administration Officer

VISITING SCIENTISTS AND ASSOCIATES

R. Acharya (Lebanon/India) J.J. Giambiagi (Argentina) D. A. Akyeampong (Ghana) A. Giovannini (Italy) Saqeba Ali (Pakistan) I. T. Grodsky (USA) R. L. Anderson (USA) G. GySrgyi (Hungary) M. S, Baghdadi (Syrian Arab Republic) M, Grypeos(Greece) L. C. Biedenharn3 (USA) F. Hadjioannou (Greece) C. G. Bollini (Argentina) C. R. Hagen (USA) A. BBhm (USA/F. R. Germany) J. Hamilton (Nordita/UK) L. Castell (F. R. Germany) R. Hermann a (USA) J. M. Charap (UK) R. Ingraham a (USA) G. Cocho Gil (Mexico) G. C. Joshi (UK/India) C.L. Cook (New Zealand) V.G. Kadyshevsky (USSR) R. Dashenb (USA) S. Kamefuchi (Japan) A. de Rfijula (Spain) H.M. Kleinertb (USA/F. R. Germany) R. Delbourgo (UK) T. Kobayashi (lapan) S. Deser (USA) S. Komy (UAR) D. Dillenburg® (Brazil) C.P. Korthals Altesb (Netherlands) H. D. Doebner a (F. R. Germany) H. P. Lehmann(F. R. Germany) G, Domokos (Hungary) N. Limid (Yugoslavia) Y. Dothan (Israel) A. Maduemezia (Nigeria) K. E. Eriksson (Sweden) M. Martinis (Yugoslavia) G. Feldman (USA/Canada) G. Marx (Hungary) E. Ferreira (Brazil) M. A. Melvin (USA) J. Fischer (Czechoslovakia) A. N. Mitra (India) H.M. Fried (USA) C. E. Moore (Ghana) C. Fronsdal (USA) L. A. Nath (Pakistan) M. Gavrila (Romania) F.N. Ndili (Nigeria)

a Partially supported by the Centre. b No financial support from the Centre. c Special service agreement.

138 TRIESTE 139

ANNEX A (cont.)

J.B. Niederle (Czechoslovakia) K. Schilcher (Lebanon/F. R. Germany) L. Pande (India) E.J. Schremp(USA) G. A. Papini (Italy) D.J. Shay (USA) J.C. Patia (India) K. T. Shah (Lebanon/Pakistan) i.C. Polkinghorne (OK) J. A. Strathdee (UK/USA) P. N. Poulopoulos (Greece) P. Suranyi (Hungary) R. Raczka (Poland) A. Syed (Pakistan) A. Ramakrishnan (India) W. Thirring (Austria) c M. A. Rashid (Pakistan) J. Tiomno (Brazil) L. Ryderb (UK) I. T. Todorov (Bulgaria) I. Saavedra (Chile) E. van der Spuy (South Africa) b B. Sakita (Japan) W. W. Wada (USA) J.J. Sakurai (USA/Japan) K.C. Wali (USA/India) D. Sankaranarayana (India) R.L. Warnock (USA) R.M. Santilli (Italy) M. Whippman (USA/UK) J. Sawicki (Austria) P. Winternitz (Czechoslovakia) R. P. Saxena (India) J. Yellin (USA)

GUEST LECTURERS

F. Arecchi (CERN/Italy) M. V. Mihailovi£ (Yugoslavia) J. S. Ball (USA) P. Mittner (CERN/Italy) A. O. Barut (USA/Turkey) Y. Ne'eman (Israel) L. Bertocchi (CERN/Italy) E. Remiddi (Italy) F. Duimio (Italy) M. Scadron (UK) E. Fenyves (Hungary) W. Selove (USA) H. A. Ferwerd a (Netherlands) D. H. Sternheimer (France) M. Flato (France/Israel) M. Toller (CERN/Italy) S. Fubini (Italy) J.L. Uretsky (USA) G. KSllen (Sweden) B. Vitale (Italy) H. A. Kastrup (F. R. Germany) J. Ward (USA/UK) G. Mack (F. R. Germany) K. Zalewski (Poland) T.A.J. Maris (Brazil)

From the Advanced School of Physics

D. Amati (Italy) G. Furlan (Italy) E. Predazzi (Italy)

CONSULTANTS

G. F. Bassani (Italy) G. Jacob (Brazil) G. Beck (Argentina) L. Infeld (Poland) D. I. Blokhintsev (USSR) H. K. Shepard (USA) N. N. Bogolubov (USSR) I. Ulehla (Czechoslovakia) A. Bohr. (Denmark) J. M. Ziman (UK) G. Caglioti (Italy)

a Partially supported by the Centre. b No financial support from the Centre. c Special service agreement. 140 ANNEXES

ANNEX A (cont.)

VISITORS FROM FEDERATED INSTITUTES

R. Baier (Austria) J. Olszewski (Poland) P. B6na (Czechoslovakia) P. Pajas (Czechoslovakia) P. ColiC (Yugoslavia) J. Patera (Czechoslovakia) I. Djbrowski (Poland) P. Pesec (Austria) A. Frenkel (Hungary) M. Pindor (Poland) J. Grabowski (Poland) V. Sachl (Czechoslovakia) F. Janouch (Czechoslovakia) L. Sips (Yugoslavia) A. Jurewicz (Poland) A. Szymacha (Poland) I. Kwiecifiski (Poland) D. Tadie (Yugoslavia) N. LimiS (Yugoslavia) J. Tolar (Czechoslovakia) J. Mozrzymas (Poland) F. Widder (Austria) T. Nagy (Hungary) N. Zovko (Yugoslavia) M. Noga (Czechoslovakia)

FELLOWS

Nuclear physics group High-energy physics group

A.Y. Abul-Magd a (UAR) C. Aragone (Uruguay) D. Bogdan (Romania) V.S. Bhasin (India) M. Grypeos (Greece) A.A. Maduemezia c (Nigeria) J. Hendekovid (Yugoslavia) L. Masperi (Argentina/Italy) K. Kan (China) M. Mateev (Bulgaria) J.H. Naqvi b (India) C.O. Nwachuku (Nigeria) Shamsher Ali (Pakistan) M. Samiullah b (India) R. Ramachandran (India) P.P. Srivastava (Brazil) M. Swiecki (Poland)

a Has been appointed as an Associate Member of the Centre. His appointment starts from 1 January 1968. b UNESCO fellow. c Holding a visiting scientist's position since July 1967. ANNEX B

THE INTERNATIONAL COURSE ON NUCLEAR PHYSICS LECTURERS AND SEMINAR LECTURERS

LECTURERS AND SEMINAR LECTURERS

DIRECTORS

A. DE-SHALIT (Israel) C. VILLI (Italy)

LECTURERS

W. E. Frahn (South Africa) M. tv'oshinsky (Mexico) J. Humblet (Belgium) E. R. Rae (UK) R.H. Lemmer (USA) G. Ripka (France) J. E. Lynn (UK) D.J. Rowe (UK) G. S. Mani (India) G. M. Temmer (USA) K. W. McVoy (USA) F. Villars (USA)

SEMINAR LECTURERS

G. Alaga (Yugoslavia) P.. Kramer (F. R. Germany) V. Benzi (Italy) W. Laskar (France) L. Biasini (Italy) C. Lolli (Italy) F. Calogero (Italy) C. Noack (F. R. Germany) K. Dietrich (F. R. Germany) R. Ricci (Italy) A. Faessler (F. R. Germany) M. Riou (France) L. Fonda (Italy) M. Schneider-Ludovici (Italy) M. E. Haglund (France) P. To in 5 £ (Yugoslavia) F. Janouch (Czechoslovakia) L. Trlifaj (Czechoslovakia) M. Jean (France) V. G. Soloviev (USSR)

THE MIDDLE EASTERN REGIONAL RADIOISOTOPE CENTRE FOR THE ARAB COUNTRIES, CAIRO

I. INTRODUCTION

During its fifth year, the Centre continued its activities according to the programme adopted by its Governing Body. The Centre's Governing Body consists of: (a) One representative of the Host State (United Arab Republic); (b) Three representatives of the Participating Arab States to be elected by them; and (c) The Director General of the International Atomic Energy Agency or his representative. In 1967 the three elected Members were: Libya, Iraq and Kuwait. Ob- servers from, the Participating States attended the meetings of the Governing Body. During 1967 the Governing Body held two sessions at which it adopted 30 resolutions. Among them: the approval of the Centre's Accounts for the year 1966, the approval of the Annual Report for 1966, the adoption of the scientific programme for 1968, the adoption of the budget for 1968, the organization of a scientific symposium to be held in 1968 on the use of isotopes in fertilizer —water-plant relationship, the approval of the outline of a hydrological project to be undertaken in the deserts of Libya, the U. A. R., the Sudan and Chad, the study of industrial applications of radioisotopes in Arab States, and the evolution of the Centre after 19681.

1. SPECIAL VISITS

In accordance with the Governing Body's resolution to encourage the participation of non-member Arab States in the activities of the Centre, the Director visited Khartoum. He was able to point to the useful co-operation between the Sudan and the Centre, 23 Sudanese trainees having passed through the training courses at Cairo; in addition there are two research projects being run in the Sudan in the fields of agriculture (fertilizer study) and medicine (goitre study). A meeting with members of the Secretariat of the Organization for African Unity at Addis Ababa enabled the Director of the Centre to intimate the possibility that the Governing Body would consider amending the terms of the agreement on the establishment of the Centre to enable African States to join in the operation and activities of the Centre.

1 The complete Annual Report of the Centre may be obtained under report number Sc.REP./lO (1968).

145 II. THE SCIENTIFIC PROGRAMME OF THE CENTRE

The scientific programme adopted for the Centre is: (a) Training specialists in the application of radioisotopes in science, industry, agriculture and medicine; and (b) conducting research using radioisotope techniques ir.: hydrology, agriculture, entomology and medicine.

1. TRAINING

The Centre organized a four-month training course, from 1 April to 31 July 1967, in agriculture, medicine and science2. The course comprised three periods: (1) an initial period of 5 weeks (1 April - 3 May 1967) devoted to lectures and experiments in basic sciences; (2) a second period of 5 weeks (6 May - 7 June 1967), devoted to three special programmes in agriculture, medicine, basic sciences; and (3) a third period of l\ weeks (8 June - 31 July 1967) devoted to participation in the research projects carried out by the Centre. The twenty trainees, selected from the 88 applicants, were distributed as follows: Agriculture - Jordan (1), Sudan (1), Syria (2), U.A.R. (5); Medicine - Sudan (2), U.A.R. (4); Science - Iraq (2), U.A.R. (1), Yemen (1), Kuwait (1). For the year 1968, it is proposed to hold a long-term training course similar to the course organized in 1967. The number of places for trainees is to be alloted as 10 from the Arab Countries other than the U. A. R., and 10 from the U. A. R. The course will last 4 months, and cover the fields of agriculture, medicine and science. In addition a second two-months special training course on the industrial applications of radioisotopes would be organized during the second half of 1968, if budgetary circumstances allow.

2. RESEARCH

Research projects, summaries of which are included in the 1966 annual report of the Centre (Sc. REP./8), have been continued through 1967. In addition, the IAEA had decided to provide funds for the following five research projects to be carried out by the Centre's Staff Members.

(a) The investigation of the Wadi El-Natrun aquifer, including determination of effective porosity, permeability, storage coefficient and transmissibility, using various radioisotopes.

2 The syllabus of the courses are to be found in previous annual reports: Agriculture - IAEA Laboratory Activities, First Report, Technical Reports Series No.25 (1964) 22-4. Medicine - IAEA Laboratory Activities, Second Report, Technical Reports Series No.41 (1965) 29-35. Basic Sciences - IAEA Laboratory Activities, First Report, Technical Reports Series No.25 (1964) 19-20.

146 CAIRO 147

(b) Research work within the framework of a co-ordinated programme on the application of radiation techniques in water-use efficiency studies. (c) Studies on ecological factors affecting control of the Mediterranean fruit fly, Ceratitis capitata Wied., by the sterile male technique in the U. A. R. (d) Haematological radioisotope studies in bilharziasis in the U. A. R. (e) Radioisotope studies in iodine metabolism in endemic goitre in countries of the Middle East.

Work on these above mentioned research projects forms part of the research activities of the Centre.

2.1. Hydrology

2.1.1. Determination of effective porosity of the Wadi El-Natrun aquifer

In two localities in the Wadi El-Natrun area tritiated water was injected in piezometers 50 metres from the pumping wells at which the tritium was monitored at regular intervals. Results were in good agreement with those previously obtained by injection of 131I in piezometers located at 10 metres from the pumping wells, and showed that distant piezometers could be used in such experiments when tritiated water is injected.

2.1.2. Determination of the velocity of groundwater flow in Wadi El-Natrun aquifer

Radioactive iodine (150 mCi 131I) was injected in a piezometer drilled on the expected direction of the flow near a pond where the groundwater is discharging naturally. From the monitoring of the activity at the pond the velocity of the groundwater flow was found to be 5. 5 cm/h, a result which is in agreement with conventional hydrological studies.

2. 1.3. Study of the dispersion of tracers in aquifers using a sand-box model basin

30 mCi of 131I was injected in three piezometer holes situated at 0. 30 m, 0. 92 m and 1. 24 m from a central pumping well. From the monitoring of the activity at the central well, skewed tracer-time concentration curves were observed. The assymetry of the curves in this case was not due to the adsorption of the activity by the formation particles, because the same assymetry was also observed when tritiated water was used as a tracer.

2. 1.4. Study of the effective porosity in the case of partially penetrated wells

Experiments were undertaken in the sand-box model using two piezometers 0. 59 m and 0. 92 m distant from the central pumping well. 148 II. SCIENTIFIC PROGRAMME

The effective porosity of the sand was first determined applying the previously determined method. For partial penetration experiments well depths of 0. 20 m and 0.40 m were used. Radioactive iodine 131I was injected in each of the piezometers at the depth facing the well screen. It was found that the values for the effective porosity obtained by applying an approximation for the equipotential surface were in reasonable agreement with the correct value.

2. 1.5. Groundwater investigations in the Nile Delta, U.A.R.

A preliminary experiment to determine the effective porosity in a locality in the middle of the Delta (Berket El-Sabba) was made using radioactive iodine, applying the technique developed at the Centre which uses 3 deep observation wells and four surface test piezometers equipped with automatic recorders.

2. 1.6. Hydrochemical investigations and dating of groundwater inU.A.H,, Libya and Sudan

As it is stated in the previous annual report (for 1966), the aim of this project is to investigate the groundwater resources in the part of the Great Sahara that covers the western desert of the U. A. R., the Libyan desert, and the desert of Northern Sudan. During 1967, more samples of groundwater were collected from U.A.R. (New Valley) and Libya. Most of these samples were analysed for major constituents; and activation analyses have been undertaken for trace elements. Dating of some samples has been carried out.

2.2. Agriculture

2.2.1. Co-ordinated research programme on the application of radiation techniques to water-use efficiency studies

The studies on evapotranspiration of maize crop in Giza, U.A.R. which has been carried out by the group in 1966 showed that the potential evapotranspiration after Penman, for the whole growing season, was in good agreement with the actual evapotranspiration, and that certain corrections for this total could be made from accumulated data. It was found also that the indirect determination of moisture in the soil profile using the data of the neutron moisture meter can be satisfactorily used after certain corrections. As recommended at the contractors meeting in March 1967, it was decided that a repetition of the experiment would add support to the results. The following data were obtained, following the IAEA recommendations:

(i) Plants. The average heights of plants along the growing season, the number of plants harvested, weight of dry grain, moisture content of grain, and weight of fresh stalk at maturity as well as yield of lysimeters, plots, and field were estimated. CAIRO 149

(ii) Evapotranspiration. The direct measurements of the actual evapotranspiration obtained from the climatological data obtained from a screen some 200 metres from the site of the experiment.

(iii) Tensiometers. Four sets of tensiometers were inserted in the experiment as follows: 2 sets in lysimeters at depths of 50, 100, 150 cm from the soil surface. 2 sets in plots at depths of 50, 100, 150, 175 cm from the soil surface. The measurements obtained from the tensiometers for lysimeters and plots were recorded.

The discussion of these results is being prepared at present.

According to the suggestions made at the meeting of March 1967, the second experiment is being carried out on a leguminous plant (Vicia faba) which had been sown in plots and lysimeters on 15 November 1967.

2.2.2. Nitrogen and phosphorus fertilization of wheat using labelled fertilizers

As reported in the Centre's report (1966), two field experiments were carried out, in the Sudan (Khartoum University) and in U. A.R. (Alexandria University farm) using labelled superphosphate to study the effect of different forms and amounts of nitrogenous fertilizers on phosphorus utilization by wheat. Plant samples were analysed for 32P and 31P. The uptake of soil and fertilizer phosphorus by plants was determined. The results are being statistically analysed. The field experiments using i5N were not carried out last year because the isotope was only received in January 1966. This was very late date for planting wheat in the field; hence pot experiments only were conducted using 15N as ammonium sulphate. Three pot experiments were carried out using soils from different locations, a calcarious soil from Maryut, a loamy soil from Cairo University farm and a sandy loam soil from Ain Shams University farm. The aim of the experiment is to study the effect of time of nitrogen application on growth and the utilization of the added nitrogen at different stages of growth. The residual effect of the nitrogenous fertilizer will also be studied. Statistical analysis of the results obtained is in progress. The following general conclusions can be deduced:

(a) Percentage of nitrogen in the plant decreases with its age. (b) In the first sample (tillering stage) the nitrogen percentage in the samples of the plants which did not receive any nitrogenous fertilizer was almost of the same order of magnitude as for the other treatments. This is probably due to the low efficiency of utilization of the added nitrogen, since it seems that the plants at this stage of growth had not yet developed extensive root systems. (c) Generally, the percentage of nitrogen in the plant increased with nitrogen application. In the second sample, the nitrogen percent in the plants of treatment C (all nitrogen applied at tillering) was the highest as compared with the other treatments. On the other hand, nitrogen percentages of treatments E, F, G and H fluctuated over a narrow range. 150 II. SCIENTIFIC PROGRAMME

(d) Treatment D (all nitrogen applied at ear emergence) showed the lowest nitrogen percentage, dry weight and yield as compared with the other treatments. It was, therefore, replaced with another treatment where one third of the nitrogen is to be applied at seeding and the rest at tillering stage.

The following studies have been carried out:

(i) Concerning the study on soil phosphorus evaluation as estimated by L (and K) values, the results obtained have been published in the Journal of Soil Science, U.A.R. (ii) A study of the influence of soil moisture conditions on phosphorus uptake by corn and on the efficiency of the added superphosphate was carried out. The work will be prepared for publication. (iii) An experiment was carried out in pots to study the effect of the following treatments: (1) The water regime; (2) The nitrogen fertilization; (3) The sodium water; and (4) The calcium water. 31 P and 32 P were determined in the plant stems plus leaves and roots. Statistical analysis and interpretation of the obtained results are underway. (iv) With regards to the study of the dependence of photosynthetic yields on the water and mineral supply, the results obtained by using the double labelling technique had been published.

2.3. Entomology Studies on the potential use of the sterile male technique for control or eradication of Anopheles pharoensis Theo. were continued. These included studies on flight range, dispersion and absolute population density in an experimental area in Fayoum Province, using the release- recapture technique. A known number of 32P tagged and sterilized An. pharoensis adults were released monthly from a fixed release site. Daily counts were made of adults found in the twenty trapping stations, distributed in concentric rings from the release site up to a maximum distance of 20 kilometres from the release site. Studies on the control of the Mediterranean fruit fly, Ceratitis capitata Wied. by the sterile male technique were continued. Labora- tory studies were carried out to determine the sterilizing dose of gamma- radiation from 60Co for the Egyptian strain of this fly. Experiments were carried out to study the competitiveness of the sterilized flies to normal flies in the laboratory. Ecological field studies on C. capitata were continued. The population density of the fly was studied throughout the year on different host fruits. The dispersion and flight range of the sterilized flies were studied in the experimental area using the release-recapture technique of marked flies using fluorescent dyes.

2.4. Medicine 2.4.1. Bilharziasis research The present haematological studies in bilharziasis in the U.A.R. are the continuation of previous radioisotope studies related to changes in the blood volume in the same disease. CAIRO 151

Urinary blood loss in various stages of uncomplicated urinary bilharziasis was assessed by means of a well-standardized technique, based on the use of 59Fe. Average results obtained so far seem to de- monstrate an intermittent and very variable average blood loss per day. This blood loss does not seem to be correlated with the daily ova discharge, which shows a maximum peak around noon, whereas most of the blood shed is lost in the afternoon. Studies on red cell survival with sicr-labelled red cells resulted in normal 51Cr values for most urinary bilharziasis cases studied up to the present. Some cases of urinary bilharziasis presented no appreciable urinary blood loss but continuous and considerable faecal blood loss. In most of these cases the cause was found to be some other unrelated organic colonic disorders, e.g. ulcerative colitis. However, some cases presented deep infiltrations with S. haematobium in the rectal mucosa. Studies on intestinal bilharziasis faecal blood loss showed an intermittent irregular periodicity, periods of bleeding being in some cases very prolonged. Blood loss was found at a very early stage in some cases which had no marked intestinal pathology but presented involvement of the liver and the spleen. The sudden increase of this daily blood loss, probably originating from the upper gastrointestinal tract, was usually followed by severe haematemesis a few days after. Red cell survival in intestinal bilharziasis was found to be usually within the normal range, as in urinary bilharziasis. Only those advanced cases with liver and spleen involvement presented, in some instances, a moderate shortening of the red cell life span. Use of external counting and scanning techniques did not reveal an abnormal sequestration of red cell by liver and spleen. Those cases presenting abnormal high counts were found to be concomitantly affected by other diseases characterized by abnormal liver and spleen sequestration of red cells. Intestinal absorption studies with 131I-triolein and 131I-oleic acid by estimation of their respective blood levels revealed a rather normal pattern except for those cases suffering from diarrhoeal episodes. The mild derangement in absorption found in some of the cases does not seem . to be related to any pancreatic enzymatic malfunction. Red cell life span was found to be normal in patients with ancylosto- miasis. Indication of red cell life span shortening was found in those severely anaemic cases presenting a non-homogeneous red cell population. No final conclusions have been made yet on the current ferro-kinetic studies on bilhar.ziasis. The workers are counting simultaneously 59Fe and 51Cr on the basis of a differential threshold counting technique which they have found to be more accurate than the one based on the use of a lead shield. 2.4.2. Goitre research The investigations carried out at the Guedida oasis in the Libyan desert were aimed at demonstrating whether there were, or not, differences in iodine metabolism between patients with goitre dwelling in an iodine deficient area and patients with sporadic goitre living in a non-iodine-deficient area. The clinical screening involved more than 2500 individuals. One hundred and twenty six cases, divided in two groups, were studied by 152 II. SCIENTIFIC PROGRAMME means of a battery of tests, e.g. radioiodine uptake and potassium perchlorate discharge test; 131PBI and conversion ratio, urinary excretion of iodine; chromatography of iodinated compounds in the blood and urine, and electrophoresis for abnormal iodinated compounds. A number of special tests were also carried out in special cases, e.g. radioactive iodotyrosine excretion test, thiourea 35 S uptake by the thyroid and determination of free thyroxine index. The first group comprised 56 cases, all of them living in the Guedida oasis, a well-known endemic goitre area. Results suggest that those cases fall into two subgroups. The findings in one subgroup are consistent with the existence of severe iodine deficiency. The other subgroup, probably not so homogeneous, consisted of patients presenting a lesser degree of iodine deficiency and also a few cases which were most probably not due to iodine deficiency at all. Further studies will be carried out to further elucidate the differences between the two subgroups. A preliminary study was made at Jable Marra Darfur, Sudan, another well-known endemic goitre area, where no modern studies had been made up to now. Several places, covering a large area, were visited with the primary aim of determining the prevalence of goitre. The screening comprised a total number of 2500 individuals, as mentioned above. Incidence of goitre was found to be, in some places, as high as 90%. Samples of water, soil, local salt and items of food were also collected from different sites of Jabel Marra for determination of inorganic iodine and goitrogens. Further studies will be carried out in the future in the district of Jabel Marra, in order to study the pattern of iodine metabolism in the inhabitants of different parts of the district.

2.5. Laboratory, research and training facilities

In 1967 the International Atomic Energy Agency provided the Centre with a single-channel gamma spectrometer. The Centre's fruit-fly breeding laboratories in the faculty of science, Cairo University, have been completed. The installation for the release of malaria mosquitoes in Fayoum Governorate was also completed. These are additions to the equipment and facilities of the Centre described in the booklet "The Radioisotope Centre, Atomic Energy Establishment, UAR (1962)" and in the earlier annual reports in the IAEA Laboratory Activities series. (Technical Reports Series Nos. 25 (1964), 41 (1965)). III. PUBLICATIONS ON WORK DONE AT THE CENTRE3

HAZZAA, I.B., GIRGIS, R.K., SAAD, K.F., SWAILEM, F.M., BAKR, A.A., Investigation of ground water radial flow using radioactive tracers, Bull. Int. Assoc. sci. Hydrology 12 3 (1967) 55.

HAZZAA, I.B., SAAD, K.F., GIRGIS, R.K., WAHBY, F., Chemical Analysis and Radioactivity of the Ground-Water in Wadi El-Natrun Area. J. Egypt, med. Assoc. jiO 11/12 (1967) 671.

HAZZAA, I.B., GIRGIS, R.K., REFAIE, S., Dispersion of radioactive tracers in a model basin sandy aquifer, Bull. Int. Assoc. sci. Hydrology 12 4 (1967) 75.

HASSAN, H.M., ABDEL-WAHAB, M.F., SOBHY, C.M., MEGAHED, Y.M., Study of the dependence of photosynthetic yields on the water and mineral supply, Part II — Effect of salinity on vicia faba seedlings, Isotopenprixis 3 6 (1967) 224-29.

ABDEL-WAHAB, M.F., HASSAN, H.M., SOBHY, C.M., Study of the dependence of photosynthetic yields on water and mineral supply. Part III — Effect of mineral deficiency on photosynthesis using double labelling technique, Isotopenpraxis (in press).

ABDOU, Fayez M., OSMAN, A.Z., Soil phosphorus evaluation as estimated by L- and K-values. U.A.R. J. Soil Sci. 7 2 (1967) 61-70.

MOUSA, A.H., EL-GAREM, A., SAIF, M., ZEIN-EL-ABDIN, A., The significance of estimating the hepatic blood flow in hepatosphenic bilharzial cases by the radiogold clearance and uptake methods and its value in determining the extent of portasystemic collaterals, J. trop. Med. Hyg. _70 (1967) 55.

Scientific reports

The investigation of the Wadi El-Natrun aquifer, including determination of effective porosity, permeability, storage coefficient and transmissibility, using different radioisotopes, IAEA Research Contract NO.302/RB (1967).

Research work within the framework of a co-ordinated programme on the application of radiation techniques in water-use efficiency studies, IAEA Research Contract No.310/RB (1967).

Studies on ecological factors affecting control of the Mediterranean fruit fly, Ceratitis capitata Wied., by the sterile male technique in the U.A.R., IAEA Research Contract No.408/OB (1967).

Haematological radioisotope studies in bilharziasis in the U.A.R., IAEA Research Contract No.457/RB (1967).

Radioisotope studies on iodine metabolism in endemic goitre in countries in the Middle East, IAEA Research Contract No.478/RB (1967).

3 The following are additions to the articles given in the Centre's 1966 annual report (pp. 18-20).

153 IV. FINANCE

The Agency supported the Centre during 1967 under the Technical Assistance Component of the United Nations Development Programme. The financial statement for the Technical Assistance portion of the Centre's accounts as at the end of 1967 is given below (in US$):

Obligations Prior years' Obligations Disbursements as at 31.12.67 Alloted to: obligations incurred in 1967 (to be carried forward (carried over) in 1967 into 1968)

Experts 2 150 1310 3 460 -

Fellowships 790 7680 7 720 750

Equipment 17680 3900 6 620 14 960

TOTALS 20 620 12 890 17 800 15 710

In addition to the Agency's contribution, the main portion of the operating costs of the Centre are met by a cash contribution of 35 000 Egyptian pounds (approx. US$77 000) from the host country and annual pledges from the participating Arab countries (approx. US$ 17 000 in 1967). All the facilities available at the Centre have been provided by the host government free of charge.

154 ANNEX A

RESEARCH TEAMS AT THE CENTRE

ISMAIL B. HAZZAA (U. A.R.) DIRECTOR

HYDROLOGY TEAM

I.B. Hazzaa (U.A.R.) M.M. Mahdi (U.A.R.) M.S. Youssef (U.A.R.) Y.Z. Shuhaiber (Kuwait) R.K. Girgis (U.A.R.) A-F. Eskengi (Libya) A-R.A. Abdel-Rassoul (U.A.R.) F.M. Swailem (U.A.R.) K.H. Hefny (U.A.R.) A.A. Bakr (U.A.R.) A. El-Sharhan (Kuwait) S.M. Refaai (U.A.R.) N.S. Akhras (Kuwait) N.Kh. Ghattas (U.A.R.)

AGRICULTURE TEAM

A.Z. El-A' jdine (U.A.R.) F. El Khalisi (Iraq) M.A. Abdel Saiam (U.A.R.) N.F. Kheir (U.A.R.) A-M. Balba (U.A.R.) Y.H. El-Sháfiey (U.A.R.) H.M. Hassan (U.A.R.) Camilla M. Sobhy (U.A.R.) F. Madi (U.A.R.) H. Bassiouni (U.A.R.) M.M. Abdalla (U.A.R.) M.E. Alninna (U.A.R.) K.A. Agabawi (Sudan) S.I. Abdel-Aal (U.A.R.)

ENTOMOLOGY TEAM

M. Hafez (U.A.R.) M.M. Ibrahim (U.A.R.) A.A. Abdel-Malek (U.A.R.) A-F.M. Wakid (U.A.R.) A-A.O. Tantawy (U.A.R.) A.S. Abdel-Aziz (U.A.R.) Laila M. El-Gazzar (U.A.R.)

MEDICINE TEAM

M.M. Badr (U.A.R.) M.S. Ibrahim (U.A.R.) M. Saif (U.A.R.) S. Zayed (U.A.R.) M.F. Abdel-Wahab (U.A.R.) A-R.A. Hafeez (U.A.R.) Y.M. Megahed (U.A.R.) IAEA SALES AGENTS

Orders for Agency publications can be placed with your bookseller or any of our sales agents listed below :

ARGENTINA FINLAND Comision Nacional de Akateeminen Kirjakauppa Energia Atomica Keskuskatu 2 Avenida del Libertador Helsinki General San Martin 8250 FRANCE Buenos Aires - Sue* 29 Office international de AUSTRALIA documentation et librairie Hunter Publications, 48, rue Gay-Lussac 23 McKillop Street F-75, Paris 5e Melbourne, C.l G E R M A N Y , Federal Republic of AUSTRIA H. Oldenbourg Georg Fromme & Co* Rosenheimer Strasse 145 Spengergasse 39 8 Munich 8 A-1050, Vienna V HUNGARY Kultura BELGIUM Hungarian Trading Co. for Books Office international de librairie and Newspapers 30, avenue Marnix P.O.B. 149 Brussels 5 Budapest 62 BRAZIL ISRAEL Livraria Kosmos Editora Heiliger and Co. Rua do Rosario, 135-137 3 Nathan Strauss Street Rio de Janeiro Jerusalem Agencia Expoente Oscar M. Silva Rua Xavier de Toledo, 140*1® Andar ITALY (Caixa Postal No. 5.614) Agenzia Editoriale Intemazionale Sao Paulo Organizzazioni Universali (A.E.I.O.U.) Via Meravigli 16 BYELORUSSIAN SOVIET SOCIALIST Milan REPUBLIC JAPAN See under USSR Maruzen Company Ltd. CANADA 6, Tori Nichome The Queen's Printer Nihonbashi Ottawa, Ontario (P.O. Box 605) Tokyo Central CHINA (Taiwan) Books and Scientific Supplies MEXICO Service, Ltd., Libreria Internacional P.O. Box 83 Av. Sonora 206 Taipei Mexico 11. D.F.

CZECHOSLOVAK SOCIALIST REPUBLIC NETHERLANDS S.N.T.L. N.V. Marlinus Nijhoff Spolena 51 Lange Voorhout 9 Nove Mesto The Hague Prague 1 NEW ZEALAND DENMARK ffhitcombe & Tombs, Ltd. Ejnar Munksgaard Ltd. G.P.O. Box 1894 6 Norregade Wellington. C.l Copenhagen K NORWAY SWITZERLAND Johan Grundt Tanum Librairie Payot Karl Johans gate 43 Rue Grenus 6 Oslo 1211 Geneva 11

PAKISTAN TURKEY Karachi Education Society Librairie Hachette Haroon Chambers 469, Istiklal Caddesi South Napier Road Beyoglu, Istanbul (P.O. Box No. 4866) UKRAINIAN SOVIET SOCIALIST Karachi 2 POLAND REPUBLIC See under USSR Osrodek Rozpowszechniana Wydawnictw Naukowych UNION OF SOVIET SOCIALIST Polska Akademia Nauk REPUBLICS Pa-foc Kultury i Nauki Mezhdunarodnaya Kniga Warsaw Smolenskaya-Sennaya 32-34 Moscow G-200 ROMANIA Cartimex UNITED KINGDOM OF GREAT Rue A. Briand 14-18 BRITAIN AND NORTHERN IRELAND Bucares t Her Majesty's Stationery Office P.O. Box 569 SOUTH AFRICA London, S.E.I Van Schaik's Bookstore (Pty) Ltd. Libri Building UNITED STATES OF AMERICA Church Street National Agency for (P.O. Box 724) International Publications, Inc. Pretoria 317 East 34th Street New York, N.Y. 10016 SPAIN Librena Bosch VENEZUELA Ronda de la Universidad 11 Sr. Braulio Gabriel Chacares Barcelona Gobernador a Candilito 37 Santa Rosa Ha SWEDEN (Apartado Postal 8092) C.E. Fritzes Kungl. Hovbokhandel Caracas D.F., Fredsgatan 2 Stockholm 16 YUGOSLAVIA Jugoslovenska Knjiga Terazije 27 Belgrade

IAEA publications can also be purchased retail at the United Nations Bookshop at United Nations Headquarters, New York, at the news-stand at the Agency's Head- quarters, Vienna, and at most conferences, symposia and seminars organized by the Agency. In order to facilitate the distribution of its publications, the Agency is prepared to accept payment in UNESCO coupons or in local currencies. Orders and inquiries from countries where sales agents have not yet been appointed may be sent to :

Distribution and Sales Group, International Atomic Energy Agency, Karntner Ring 11, A-1010, Vienna I, Austria INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA, 1968

PRICE: US $1.00 Austrian Schillings 26,- (£0.8.4; F.Fr. 4,90; DM 4,-)