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ASTM D3649-2006 水的高分辩率γ射线光谱测定法的标准实施规范

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【英文标准名称】:StandardPracticeforHigh-ResolutionGamma-RaySpectrometryofWater
【原文标准名称】:水的高分辩率γ射线光谱测定法的标准实施规范
【标准号】:ASTMD3649-2006
【标准状态】:现行
【国别】:
【发布日期】:2006
【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】:D19.04
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:γ辐射;放射性;分辨率;光谱测定法;水
【英文主题词】:gamma-rayspectrometry;germaniumdetectors;high-resolutiongamma-rayspectrometry;HPGe;photonspectrometry;water
【摘要】:Gamma-rayspectrometryisofuseinidentifyingradionuclidesandinmakingquantitativemeasurements.Useofasemiconductordetectorisnecessaryforhigh-resolutionmeasurements.Variationofthephysicalgeometryofthesampleanditsrelationshipwiththedetectorwillproducebothqualitativeandquantitativevariationsinthegamma-rayspectrum.Toadequatelyaccountforthesegeometryeffects,calibrationsaredesignedtoduplicateallconditionsincludingsource-to-detectordistance,sampleshapeandsize,andsamplematrixencounteredwhensamplesaremeasured.Sincesomespectrometrysystemsarecalibratedatmanydiscretedistancesfromthedetector,awiderangeofactivitylevelscanbemeasuredonthesamedetector.Forhigh-levelsamples,extremelylow-efficiencygeometriesmaybeused.Quantitativemeasurementscanbemadeaccuratelyandpreciselywhenhighactivitylevelsamplesareplacedatdistancesof10cmormorefromthedetector.Electronicproblems,suchaserroneousdeadtimecorrection,lossofresolution,andrandomsumming,maybeavoidedbykeepingthegrosscountratebelow2000countspersecond(sx2013;1)andalsokeepingthedeadtimeoftheanalyzerbelow5%.Totalcountingtimeisgovernedbytheradioactivityofthesample,thedetectortosourcedistanceandtheacceptablePoissoncountinguncertainty.1.1Thispracticecoversthemeasurementofgamma-rayemittingradionuclidesinwaterbymeansofgamma-rayspectrometry.Itisapplicabletonuclidesemittinggamma-rayswithenergiesgreaterthan45keV.Fortypicalcountingsystemsandsampletypes,activitylevelsofabout40Bqareeasilymeasuredandsensitivitiesaslowas0.4Bqarefoundformanynuclides.Countratesinexcessof2000countspersecondshouldbeavoidedbecauseofelectroniclimitations.Highcountratesamplescanbeaccommodatedbydilution,byincreasingthesampletodetectordistance,orbyusingdigitalsignalprocessors.1.2Thispracticecanbeusedforeitherquantitativeorrelativedeterminations.Inrelativecountingwork,theresultsmaybeexpressedbycomparisonwithaninitialconcentrationofagivennuclidewhichistakenas100%.Forquantitativemeasurements,theresultsmaybeexpressedintermsofknownnuclidicstandardsfortheradionuclidesknowntobepresent.Thispracticecanalsobeusedjustfortheidentificationofgamma-rayemittingradionuclidesinasamplewithoutquantifyingthem.Generalinformationonradioactivityandthemeasurementofradiationhasbeenpublished(1,2).Informationonspecificapplicationofgammaspectrometryisalsoavailableintheliterature(3-5).SeealsothereferencedASTMStandardsin2.1andtherelatedmaterialsectionattheendofthisstandard.Thisstandarddoesnotpurporttoaddressthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationpriortouse.
【中国标准分类号】:Z16
【国际标准分类号】:71_040_50
【页数】:8P.;A4
【正文语种】:


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MIL-STD-2073/1C, TRANSITION GUIDE (25 JUN 1997)., The recently issued revision to MIL-STD-2073-1 representssignificant changes in the manner by which the DOD specifiesmilitary packaging. This guide has been prepared to assist usersof this most important document in the military packaging arenato adjust to these changes and convert packaging data alreadydeveloped to the new system.
基本信息
标准名称:胶合木结构技术规范
发布部门:中华人民共和国住房和城乡建设部
发布日期:2012-01-21
实施日期:2012-08-01
首发日期:
作废日期:
出版社:中国建筑工业出版社
出版日期:2012-08-01
页数:192页
适用范围

本规范适用于建筑工程中承重胶合木结构的设计、生产制作和安装。

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1 总则 2 术语和符号 3 材料 3 基本设计规定 5 构件设计 6 连接设计 7 构件防火设计 8 构造要求 9 构件制作与安装 10 防护与维护 附录 本规范用词说明 引用标准名录 附:条文说明

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