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QB/T 1725-1993 332型工业X射线胶片

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基本信息
标准名称:332型工业X射线胶片
中标分类: 化工 >> 信息用化学品 >> 感光材料
发布部门:中华人民共和国轻工业部
发布日期:1993-04-15
实施日期:1993-12-01
首发日期:1900-01-01
作废日期:1900-01-01
出版社:中国轻工业出版社
出版日期:1993-12-01
页数:13页
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所属分类: 化工 信息用化学品 感光材料
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基本信息
标准名称:压水堆核电厂反应堆冷却剂系统设计准则
发布部门:国家能源局
发布日期:2012-10-19
实施日期:2013-03-01
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出版日期:2013-03-01
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所属分类: 农业 林业 林业 森林经营技术 农业 农业和林业 绿化和造林
【英文标准名称】:StandardTestMethodforCharacterizingtheEffectofExposuretoEnvironmentalCyclingonThermalPerformanceofInsulationProducts
【原文标准名称】:暴露于环境热循环对于保温产品的热性能的影响的标准试验方法
【标准号】:ASTMC1512-2010
【标准状态】:现行
【国别】:美国
【发布日期】:2010
【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】:C16.33
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:environmentalcycling;thermalinsulation;Thermalinsulatingmaterials;Boardthermalinsulation;Composites--buildingapplications;Environmentalcontrol/fate;Fieldfabrication;Preformedthermalinsulation;Protectivefacings;Rigidthermalinsulatio
【摘要】:Exposingaspecimentoconditionsofone-directionalenvironmentalcyclingcanincreaseitsmoisturecontentuntiladecreaseinmaterialpropertiesoccurs(ataspecificnumberofcycles).Suchatestcouldbeinappropriateduetothenumberofcyclesrequiredtocauseadecreaseinmaterialpropertiessinceproductperformanceissuesoftenariseonlyaftermanyyearsofexposure.Theuseofapreconditioningprocedureisnotintendedtoduplicateexpectedfieldperformance.Ratherthepurposeistoincreasethemoisturecontentoftestmaterialspriortosubjectingtothemtoenvironmentalcycling.Themostimportantaspectofthepreconditioningprocedureisnon-uniformmoisturedistributioninthespecimen.Theheatflowisonedirectionalcausingmoistureflowtowardsthecoldsideresultinginzonesofdrymaterialonthewarmsideandhighmoisturecontentonthecoldside.(Whetherthehighmoisturecontentzoneislocatedrightatthecoldsurfaceofthespecimenoratsomedistancefromthissurfacedependsupontemperatureoscillationandabilityofthecoldsurfacetodryoutwards).Becausethepreconditioningprocedureinvolvesthermalgradient,thispreconditioningprocedureresultsinadistributionofmoisturecontentthatmayoccurunderfieldexposureconditions.However,theresultingmoisturecontentmaydiffersignificantlyfromthatwhichmaybedemonstratedintypicalproductapplications.Thepreconditioningresultsinaccumulationofmoistureinthethermalinsulationresultingfromthesimultaneousexposuretoadifferenceintemperatureandwatervaporpressure.Thistestmethodisnotintendedtoduplicatefieldexposure.Itisintendedtoprovidecomparativeratings.Asexcessiveaccumulationofmoistureinaconstructionsystemmayadverselyaffectitsperformance,thedesignershouldconsiderthepotentialformoistureaccumulationandthepossibleeffectsofthismoistureonthesystemperformance.1.1Thistestmethodisapplicabletopreformedorfieldmanufacturedthermalinsulationproducts,suchasboardstockfoams,rigidfibrousandcompositematerialsmanufacturedwithorwithoutprotectivefacings.SeeNote1Thistestmethodisnotapplicabletohightemperature,reflectiveorloosefillinsulation.Note18212;Iftheproductismanufacturedwithafacer,testproductwithfacerinplace.1.2Thistestmethodinvolvestwostages:preconditioningandenvironmentalcycling.Duringthefirststage,25mm(1in.)thickspecimensareusedtoseparatetwoenvironments.Eachoftheseenvironmentshasaconstantbutdifferenttemperatureandhumiditylevel.Duringtheenvironmentalcyclingstage,specimensalsodividetwoenvironmentsnamelyconstantroomtemperature/humidityononesideandcyclingtemperature/ambientrelativehumidityontheotherside.1.3Thistestmethodmeasurestheabilityoftheproducttomaintainthermalperformanceandcriticalphysicalattributesafterbeingsubjectedtostandardizedexposureconditions.Acomparisonismadebetweenmaterialpropertiesforreferencespecimensstoredinthelaboratoryforthetestperiodandspecimenssubjectedtothetwo-stagetestmethod.Toeliminatetheeffectofmoisturefromthecomparison,thematerialpropertiesofthelattertestspecimensaredeterminedaftertheyhavebeendriedtoconstantweight.Theaveragevaluedeterminedforeachofthetwosetsofspecimensisusedforcomparison.1.4Differentpropertiescanbemeasuredtoassesstheeffectofenvironmentalfactorsonthermalinsulation.Thistestmethodrequiresthatthermalresistancebedeterminedbaseduponanaverageforthreespecimensmeasuredaftercompletingthetest.Secondaryelementsofthistestmethodincludevisualobservationssuchascracking,delaminationorothersurfacedefects,as......
【中国标准分类号】:Q25
【国际标准分类号】:13_020_60
【页数】:7P.;A4
【正文语种】:英语