【英文标准名称】:StandardTestMethodforMeasuringFast-NeutronReactionRatesbyRadioactivationofCopper
【原文标准名称】:用铜的放射性测量快速中子反应速率的标准试验方法
【标准号】:ASTME523-2007
【标准状态】:现行
【国别】:
【发布日期】:2007
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E10.05
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:铜;测量;中子;核能;核技术;测试
【英文主题词】:activation;activationreaction;copper;crosssection;dosimetry;fast-neutronmonitor;neutronmetrology;pressurevesselsurveillance;reactionrate
【摘要】:RefertoGuideE844fortheselection,irradiation,andqualitycontrolofneutrondosimeters.RefertoPracticeE261forageneraldiscussionofthemeasurementoffastneutronfluenceratewiththresholddetectors.Thegeneralshapeofthe63Cu(n,x03B1;)60CocrosssectionisalsoshowninFig.1(3).Thisfigureisforillustrativepurposesonlytoindicatetherangeofresponseofthe63Cu(n,x03B1;)reaction.RefertoGuideE1018fordescriptionsofrecommendedtabulateddosimetrycrosssections.Note18212;ThecrosssectionappropriateforuseunderthisstandardisENBDF/B-VIrelease8librarysinceitcontainsacovariancematrix.TheENDF/B-VIIlibraryhasbeenreleased,butitdoesnotcontainacovariancematrixforthisreaction.Fordosimetryapplications,anuncertaintymetricexpressedasacovariancematrixisrequired.SeeGuideE1018.Thechiefadvantagesofcopperformeasuringfast-neutronfluenceratearethatithasgoodstrength,iseasilyfabricated,hasexcellentcorrosionresistance,hasameltingtemperatureof1083x00B0;C,andcanbeobtainedpure.Thehalf-lifeof60Coislonganditsdecayschemeissimpleandwellknown.Thedisadvantagesofcopperformeasuringfastneutronfluenceratearethehighreactionapparentthresholdof5MeV,thepossibleinterferencefromcobaltimpurity(>1x03BC;g/g),thereportedpossiblethermalcomponentofthe(n,x03B1;)reaction,andthepossiblysignificantcrosssectionsforthermalneutronsfor63Cuand60Co(thatis4.5and2.0barns,respectively),(4)whichwillrequireburnoutcorrectionsathighfluences.FIG.163Cu(n,x03B1;)60CoCrossSection1.1Thistestmethodcoversproceduresformeasuringreactionratesbytheactivationreaction63Cu(n,)60Co.Thecrosssectionfor60Coproducedinthisreactionincreasesrapidlywithneutronshavingenergiesgreaterthanabout5MeV.60Codecayswithahalf-lifeof1925.28days(0.5days)()andemitstwogammarayshavingenergiesof1.1732228and1.332492MeV().Theisotopiccontentofnaturalcopperis69.17%63Cuand30.83%65Cu().Theneutronreaction,63Cu(n,)64Cu,producesaradioactiveproductthatemitsgammarayswhichmightinterferewiththecountingofthe60Cogammarays.1.2Withsuitabletechniques,fission-neutronfluenceratesabove109cm2s1canbedetermined.The63Cu(n,)60Coreactioncanbeusedtodeterminefast-neutronfluencesforirradiationtimesuptoabout15years(forlongerirradiations,seePracticeE261).1.3Detailedproceduresforotherfast-neutrondetectorsarereferencedinPracticeE261.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:F04
【国际标准分类号】:17_240;27_120_30
【页数】:3P.;A4
【正文语种】: