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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】:


【英文标准名称】:Medicalelectricalequipment-CharacteristicsofdigitalX-rayimagingdevices-Part1-2:Determinationofthedetectivequantumefficiency-Detectorsusedinmammography(IEC62220-1-2:2007);GermanversionEN62220-1-2:2007
【原文标准名称】:医疗电气设备.数字X射线成像装置特性.第1-2部分:探测量子效率的测定.用于X射线照相法的探测器
【标准号】:DINEN62220-1-2-2009
【标准状态】:现行
【国别】:德国
【发布日期】:2009-02
【实施或试行日期】:
【发布单位】:德国标准化学会(DE-DIN)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:一致性;数据分析;定义;诊断设备;数字的;显示装置;电气工程;电医学;乳腺X射线摄影术;测量技术;医疗放射照相术;医疗技术学;使用条件;提取系统;精密度;辐射学;放射疗法;扫描系统;规范(验收);X射线图象增强器
【英文主题词】:Conformity;Dataanalysis;Definition;Definitions;Diagnosticequipment;Digital;Displayunits;Electricalengineering;Electromedicine;Mammography;Measuringtechniques;Medicalradiography;Medicaltechnology;Operatingconditions;Pick-upsystems;Precision;Radiology;Radiotherapy;Scanningsystems;Specification(approval);X-rayimageintensifiers
【摘要】:
【中国标准分类号】:C43
【国际标准分类号】:11_040_50
【页数】:35P.;A4
【正文语种】:德语