【英文标准名称】:StandardTestMethodforDeterminingtheL/DRatioofNeutronRadiographyBeams
【原文标准名称】:中子射线照相束的长度直径比的标准测定方法
【标准号】:ASTME803-1991(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:1991
【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】:E07.05
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:beamcollimation;L/Dratio;neutronradiography;radiographicunsharpness;umbralshadow;L/Dratio;Neutronradiographictesting;NU(noumbra)technique;Radiographicexamination;Umbra
【摘要】:Thequalityofaneutronradiographicimageisdependentuponmanyfactors.TheL/Dratioisoneofthosefactorsandconstitutesanumericaldefinitionofthegeometryoftheneutronbeam.TheL/Dratiorequiredforaspecificneutronradiographicexaminationisdependentuponthethicknessofthespecimenandthephysicalcharacteristicsoftheparticularelementofinterest.Useofthistestmethodallowstheradiographerandtheusertodetermineandperiodicallychecktheeffectivecollimationratio.1.1Thistestmethoddefinesanempiricaltechniqueforthemeasurementoftheeffectivecollimationratio,L/D,ofneutronradiographybeams.Thetechniqueisbaseduponanalysisofaneutronradiographicimageandisindependentofmeasurementsandcalculationsbasedonphysicaldimensionsofthecollimatorsystem.Thevaluesderivedbythistechniqueshouldbemoreaccuratethanthosebasedonphysicalmeasurements,particularlyforpoorlydefinedapertures.
【中国标准分类号】:N78
【国际标准分类号】:19_100
【页数】:7P.;A4
【正文语种】:英语