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The Radiochemistry of Iridium-- +- -:, G ———..————- !546.8 L472ra NAS-NS 3045 .c.8 THE RADIOCHEMISTRY OF IRIDIUM-- +- -:, G. W. Leddicotte ‘1 Oak Ridge National Laboratory Oak Ridge, Tennessee October 1961 .- .- .. --.—- ---- -. ---- -. —.-. .- ---- ---- --- .- .. .- .— .— –. —-. .— —- -- -—. I -.. - -.. I ..-.- . -. I .. .. .. -- 1.- REPORT selection aids Pinpointing R & D rej9G7t8for hdu.st~ Clearinghouse, Sprhgfleld, Va, 22151 GOVERNMENT-WIDE INDEX—SEMI-MONTHLY GUIDE TO FEDERAL SCIIZNTIYIC AND TECH- NICAL REPORTS. ANNUAL SUBSCRIPTION S22.00 ($27.50 FOREIGN MAILING). SINGLE COPY $3.00. U.S. GOVERNMENT RESEARCH AND DEVELOPMENT REPORTS_EMI-MONTHLY JOURNAL ANNOUNCING R&D REPORTS. ANNUAL SUBSCRIPTION 830.00 ($27A0 FOREIGN MAILING). SINGLE COPY $3.00. FAST ANNOUNCEMENT SERVICE—SUMMARIES OF SELIZCTED R&D REPORTS MAILED ❑ Y INDUSTRIAL CATEGORIES, SS.00 ANNUAL SUBSCRIPTION. WRITE FOR AN APPLICATION FORM. DOCUMENT PRICES~FFECTIVE JANUARY 1, 19s7 THE CLEARINGHOUSE CHANGED ITS PRICING POLICY FOR DOCUMENT SALES FROM A SLIDING PRICE SCALE BASED ON DOCUMENT SIZE TO A SINGLE PRICE FOR DOCUMENTS SOLD. THE NEW DOCUMENT PRICE FOR A PAPER COPY (HARD COPY - HC) DOCUMENT IS $3.00. THE NEW PRICE FOR A MICROFICHE (MFI COPY IS s.ss PER DOcuMENT. THEsE PRICES ALSO ApPLY TO DOCUMENTS ANNOUNCED PRIOR TO JANUARY 1, 1967. THE NEW UNIT PRICES ARE BELOW THE PREVIOUS AVERAGE PRICES OF DOCUMENTS SOLD BY THE CLEARINGHOUSE. EFFICIENCIES IN ORDER PROCESSING RESULTING FROM THE SINGLE PRICE POLICY MAKE THE LOWER AVERAGE PRICE POSSIBLE. THE CLEARINGHOUSE SEL15 COUPONS FOR THE PURCHASE OF DOCUMENTS WHICH SIMPLIFY ORDERING AND HANDLING ❑ Y BOTH THE CLEARINGHOUSE AND ITS CUSTOMERS, PERMITTING THE CLEARINGHOUSE TO GIVE FASTER SERVICE ON DOCUMENT REQUESTS. THE COUPON IS A TABULATING CARD WITH A FACE VALUE OF THE PURCHASE PRICE OF A CLEARINGHOUSE DOCUMENT (S3.00 FOR HC, $.SS FOR MF). THE COUPON SERVES As THE MEDIUM OF PAYMENT AS WELL A9 THE ORDER FORM AND THE SHIPPING LABEL. THE USE OF THE CLEARINGHOUSE COUPONS IS PREFERRED FOR ALL DOCUMENT RE- QUESTS. WHEN THE COUPON IS NOT USED, PREPAYMENT IS REQUIRED BY CHECK OR MONEY ORDER MADE PAYABLE TO THIS CLEARINGHOUSE UNLESS PURCHASES ARE TO BE CHARGED TO CLEARINGHOUSE DEPOSIT ACCOUNTS. COUPONS FOR PAPER COPY (HC) DOCUMENTS ARE AVAILABLE AT $3.00 EAc H oR IN BOOKS OF 10 COUPONS FOR $30.00. COUPONS FOR MICROFICHE COPIES OF Cl-12ARING - HOUSE DOCUMENTS ARE AVAILABLE IN BOOKS OF 50 COUPONS FoR S32.50. WRITE FOR A COUPON ORDER FORM. National Academy ‘v d -; Sciences ~~ Ihk#tkmal1“Research council ‘ H NUCLEAR SCIENCE SERIES The Rctdiochemistry of Iridium COMNll~EE ON. NUCLEAR SCIENCE L.F. CURTffS, CM~ “ ROBLEY D.EVAiil%Vk8 Ckzi_ NatlonnlBureauofmaodhds ~ fnstituhofTechmloLw J.i.DMdREN, S6cwhWP we~ BleotrioCormntim .,. ., c.J.BQRKowma “““ J.W. IRVfN1l.JR. cmkflidgeN8tkmulfabom@q ~ InsumlaOfmchnalcgy ROBERT G.COCU E.D.KLEMA Texm.sAgricufhmland~ Nobtem UnfvOdW Couoge W. WA- MEINKE Udvamlw d Mlohlgmn J.J.NIC-N MOmorhfEwpiml,New York ROBERT L.PUYZU IAm9taiM &chiulia Phymiqm D.M. VAN PATf’EB Bu@Remuoh FaLuMm ,“ LIAISON MEM8ERS PAUL C.AE*LD cHWS ILEEED AtoMIoEm9rEwCamuMnim U.S.“AirForw J.HOWARDMoMLLEN ‘“ WILIJAME.WRIGHT NatlmulEdema Fmd8tloo - ofNerd Ranemh SUBCOMMITiEE ON RADIOCHEM15TRY W. WAYNE MKRWOI,Ckd!r’du UnWersi&M Mirhfgnn Uhiv?rmityd Califonlin(Berkelq) NATNAN BALWU ~ JUUAN NLEISEN NavalHMIIolagidDefti”IA&IrI@IY HanfordLabrntofies GREGORY IL~OPPIN (3.DAVfDO’KELLEY FloridaElateUniverd& OakR@@ NatlmalI.dmrntmy GEORGE A.C(XVAN LOBAhmO.9BrdentifioLabOratng ARTHUKW, FAIRHALL : PETER C.BTf2VENEON Uolwrsi&ofWmhiqtoo Univumi@ et California (14vermore) JEROME RUDIS DUANE N.8UNDffRMAN BrriokiuvrmN~oMI hbom&ory BatblleMemoriaffn.etltiti CONSULTANTS HERBERT M,.CI.ARK JOHN W. ~CRHSTER RenaOmlaOr POlybohnic Irmtimxte . Mnsmdweita Institute ofTechmlcgy c-TRY The Radiochemistry of Iridium G. W. LEDDI~ W Ridge Ndioml Lduwulwy Ckz&Ridge, T-&?See Chb3ber 1961 OCT311968 IJBRARIES PROPERTY “ Subconlmittam al Radiachel.mwtq ‘NationalAca#enw of Sciamcas-llatimal RIBBemch CmuIcil FOREWORD The Subcmemlttee on Radlochemlstry Is one of a number of aubcommltteee working under the Committee on Nuolear Science within the National Academy of Sciences - National Research council . Ita members represent gcwernment, Industrial, and university laboratories In the areas of nuclear chemistry and analytical chemL6try. The Subccmmlttee has conoerned Itself with those areaa of nuclear sc5.encewhich Wvolve the ahemist, such as the collec- tion and distribution of radiochemical procedures, the estab- lishment of speciflcatians for radioohemhally pure reagents, avallablllty of cyclotron the for service :rradlatlons, the place of radlochemlstry In the undergraduate college program, etc. This series of monographs has grown out of the need for up-to-date compilations of radlochemlcal Infomnation end pro- cedures. The Subconmd-ttee haB endeavored to present a serlee which wI1l be of maximum use to the working scientist and whl,ch contains the latest available Inf’omnatlon. Each mono- graph colleots In one volume the pertinent Infomatlon required for radiochemlcal work with an Indlvldual element or a &oup of closely related elements. An expert in the radLochemiBtry of the partloular element has written the monograph, following a standard fomnat developed by the Subcommlttae. The Atomic Energy Commission has BponBored the prtittig of the series. The Subcommittee Ie confident these publications will be; useful not only to the radlochemist but also to the research worker l.nother fields such as Dhyslcs, biochemistry oP”medlclne who wishes to uOe radiochemical-techniques to eolve-a speclfla ~roblem. W. Wayne tletnke, Chaiman Subconuni.tteeon Radl.ochemlstry iii INTRODUCTION This volume which deele with the radlochemlsmy of Irldlum 13 me of a Berlee of monogrepha on radlochemismy of Che elements. There Is includ~d a review of the nuclear and chemlcel features ~f particular interest to the radlochernlst, a discussion of prob- lems of dissolution of a sample end counting techniques, and Zlnally, a callectlon of radlochemical procedures for the element as found In che Mzerature. The series of monographs will cover all elements for which radlochemlcsl procedures are perttient. Plans Include revlslon of the monograph perlodlcelly as new techniques end procedures warrant. The reader Is therefore encouraged to call to the attenrlon of the author any published or unpublished macerlal on the radiochemlstry of Iridium which mlmt be Included In a revised version of the monograph. iv CONTENTS I. Gemre+l I?afamnces on tha Imrgnnic ad chdt3hy Orsrim . ..-. 1 II. Ttm RdLowxiremclidno of Iridium . 1 m. lll?vlwd tim~tryoflridim . 2 . 3 l.~iclridium . 4 2.~~of~~...... b a.!lheodde ~...... b. W EBllda~. : c. The alllfide,Sulfate,ad (M%omyl . 7 a. m alu ~. 7 . 7 1. &par8tion By PMCipitatlul.. 8 2. -timl BY Vol.ntility. 10 3. Seplumtion By m.ectrolyuio . 10 4. Be’plUticm~ Wvent EctrmXion . U a. Ion Associationme. U b. me18ts Co6plaxSyD-. U 5. ~tw=P4 6eRuQuw3ns . 11 a. With btx@ltiC AdEOrbantE. 11 b. With Ion Fa@umge ROOIM . 12 c. w w ~tofgwhy. K d. By B19ctro-chm=itog17@lc Metlmdo . u Ivm Dissolutionof [email protected]~IfiM~........ u v. safetyRactioen . 14 VI. countingTechlliqllasfor W! Rdloacti- Iridi= IEotoPoa. 14 VII. ~~cal ~B for tha Itim Bdionuclldse . 15 Fleferenwm . 29 v Tk Radiochemistry of Iridium G. W. LEDDICOTTE ● ClakRi@e National Laboratory Oak Ridge, Tenwssee I. GENERAL REFEFXNCES ON THE IUOK!AHICAHD ANAWIXC/&CHlmImm C??mIDIm Sidgwl(:k,N. V., The ChemicalElemnte ami Their Comp uude, p. 14AIIS28, Oxford University Press, London, 1950. Kleinberg, J., krgersinger, W. J., Jr., e+ Gtiswold, E., Inor@c Chemistq, P o 576-filj HeathB %ston (19@). Req, H., ‘%eatise on Snorgenlc Chemletry, Volw3m1, p. 334-337, Kkievler, Amaterdem (1956). Schoeller, W. R., and Powell, A. R., The Analysis of Minerals and tie of the Rarer Elements, 3rd ed., Griffin, London, 1955. Bmmish, F. E., ‘A Critical Review of Methuis For Isolating and Separding the Six Platinom Metals,” Talanta & p. 1-35 (1965). Scott,w. w., Stadard Methodsof CMIUicmlArlalysic,VoMum 1, pp. 712-728, Van Ndetrand, New Yo?k, 1939. Hillebrend, W. F., Lumiell, G. E. F., Bright, H. A., and Hoffhenj J. I., Applied Inorgauic Am@ is, Jobn Wiley, NewYork, 1953. Rodden, C. J., klyt ical Chmdstry of the Manhattan Project, pp. 3-159, 483 and 491-493, Mc&aw-Hi~l, liewyoI?4(1~). II. lMDIOA~IVE NUCIJD!ZSCtFIRIDIUl The radionuclidea of iridium that are of interestin the rsdiochemistry of iridium me given In Table 1. This Mle has been completed from hforma- (1) tion appearing In reports by Straulnger, et al and by Hughes and Hemy:2) *Operuted for U. S. Atmnlc Enerw Camnlesionby Union Carbide Corpmation 1 TABIJ?I l!HERKOIOACTTVE NUCIZDES OF IRIDIUM Rad30- Mode nuclide Half-1ife of rkcq iker~ of Radiation Produced By #87 185 11.8 h EC, 6+ !3+2.2 Re-a-2u, Re -CM% -1.3 abs os-&3n +EM 41.5 h EC, ~+ p+ 2.0 Re- Re-c+3n, -1.8 SbS Relv’7-&3n, Os-d-2n +9 3,2 h p, EC p+ 1.7 Re-en, Re’87-c+n, “’ Os-d-n,Os-d-2n #-a 1.42 m IT 0.057 SpectConv. Ir-n-y ~r192 74.37 d E(2,p- ‘ i3- 0.67 Os-d-2n, Ir-n-y, Ir-n-2u, 7 0.136,O.ml, Ir-d-p, Pt-d-a, Pt-Y-Pn ‘0.206, 0.296, 0.870 ~rlgm 5.7 x 10-9 E m 7 0.065 Daughter 0s193 #94 19.0 h P- B- 2.18, 1.g9, others Ir-n-y, I;-d-p, Pt-7-p 7 O.~, 0.z6, others +95 140 m B- ‘“ B- 1.8 abs Pt-7-p, m-n-p 7 O.kg, 0.84 +96 9d P- D 0.08 Sbs Ft-n-p +’7 7m P- P- 1.65, 0.6 aS Pt-7-p, Pt-n-pn +$8 45 s .B-”” B- 3.6 abs ‘ Pt-n-p y 0.78 III. TEE C~ OF IRIDIUM AND ITS APPLICATION 73)TEE RADIOCHIMIS!EKYOF TEE ~ItM RADIOBUCI.JDES Radiochemistry is probably best described as being an analjsi.stechnique used primarily either(l) to aseist in ubklning a pure radionuclide of some mpecific element in a suitable form so that an absolute =aeurement of its radioactivity,radiation energies.,and half-life can be made, or (2) to deter- mine the smiountof mdloactivi~ of a ~icular mdi6elenwit h a radionuclide mixture, or (3) to cmnplete”a mldloactivationenalyBlstiing used ta determine the stable‘elementconcentrationin a ~icular samplemiterial.
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