QJ 2498.12-1993 模件组合式控制台结构及尺寸系列 转角件
作者:标准资料网
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来源:标准资料网
基本信息
标准名称: | 模件组合式控制台结构及尺寸系列 转角件 |
中标分类: |
电子元器件与信息技术 >>
电子设备专用材料、零件、结构件 >>
电子设备机械结构件 |
ICS分类: |
机械系统和通用件 >>
机箱、外壳、其他机械部件
|
发布日期: | 1993-03-30 |
实施日期: | 1993-10-01 |
首发日期: | |
作废日期: | |
出版日期: | |
页数: | 11页 |
适用范围
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前言
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目录
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引用标准
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所属分类: 电子元器件与信息技术 电子设备专用材料 零件 结构件 电子设备机械结构件 机械系统和通用件 机箱 外壳 其他机械部件
【英文标准名称】:StandardPracticeforPreparationofNatural-MatrixSedimentReferenceSamplesforMajorandTraceInorganicConstituentsAnalysisbyPartialExtractionProcedures
【原文标准名称】:用部分萃取法大量和微量无机成分分析的天然杂矿石沉淀物标样的制备的标准实施规程
【标准号】:ASTMD5074-1990(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:1990
【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】:D19.07
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:Aquaticnatural-matrixbed-sedimentreferencesamples;Collaborativetesting;Inorganicchemicalanalysis--water;Inorganiccompounds--water;Natural-matrixbed-sedimentreferencesamples;Partialextractionprocedures;Referencesamples/specimens;Sampli
【摘要】:Theobjectiveofthispracticeistoprovideguidelinesforthepreparationofstable,representative,oxidized,relativelyunpolluted,aquaticnatural-matrixbed-sedimentreferencetestsamples.Whenpreparedasdescribed,suchtestsamplesshouldbeusefulforcollaborativemethodstesting,toevaluatetheprecisionandbiasoftestmethods,andtoevaluatetestmethodsperformanceduringtheirdevelopment.Theavailabilityofdefinedrepresentativenatural-matrixreferenceortestsamples,closelyapproximatingavarietyoftypicalenvironmentalsamples,isakeyrequirementfortheeffectivecollaborativemethodsevaluationanddevelopmentoftestmethods,andqualityassurancetesting.Whenthecompositionofthereferenceortestsampleshasbeendetermined,eitherforoperationallydefinedx201C;totalrecoverablex201D;leachingtechniques,orforx201C;totalanalysisx201D;determinedbytotaldissolution,thedefinedsamplesshouldalsobesuitableforanalyticalqualityassurancetesting.Certifiedanalysesofmostrock,sediment,sludge,andsoilreferencesamplesaretypicallybasedonthetotalamountofeachconstituentofinterestintheentiresample.x201C;Totalx201D;chemicalanalysisofthesesamplesgenerallyrequirescompletedecompositionordissolutionofthestandardmaterial.Thesearetheonlyfeasibleanalyticalapproachesifknowledgeoffiniteconcentrationsforeachelementofinterestintheentiresampleisrequired.Certaininstrumentalmethods,suchasX-rayfluorescenceorneutronactivationanalysis,mayprovideinformationastothetotalconstituentcompositionwithoutsampledestruction.Partialchemicalextractionofsediments,orx201C;totalrecoverablex201D;analyses(operationallydefinedprocedures)forselectingconstituents,frequentlyareusefulfordefiningx201C;availablex201D;constituentconcentrations.Inaddition,partialchemicalextractionsmayalsoprovidedataonpartitioning,phaseassociations,oronhowtraceelementsareentrained.Operationallydefinedextractabletraceconstituentconcentrationsaregenerallybestobtainedbyusingveryspecificreagentmixturesandextractionprocedures,includingmethodofmixing,vesselsizeandshape,extractiontime,temperature,andsoforth.Thevariousironandmanganeseoxidesandhydroxides,clayminerals,andorganicsolutesandparticulates,thatcommonlyoccurascoatingsonmostoxidizedsedimentparticles,aregenerallyrecognizedasthecontrolsgoverningtheconcentrationsanddistributionofmosttracemetalsinnaturalwater-sedimenthydrologicenvironments.Anthropogenicsourcesclearlydominateinthenumberofsourcesandintotalloadingtomostsystems,althoughotherfactorsmayalsobeimportant.Underreducingconditionstheironandmanganeseoxidecoatings,organiccomponents,andassociatedtracemetalsmayberesolubilizedandremobilized.Migrationofthereducedsolubilizedspecies,withpossiblesubsequentformationofsulfidesandsoforth,andreoxidationandredepositionatsomenewlocation,maythenoccur.Analysisofextractabletraceconstituentconcentrationsinleachatesobtainedfromreducedsedimentsthuswillprobablynotbeindicativeofthetraceconstituentconcentrationsinitiallyassociatedwiththeoxidizedandcoatedsedimentgrains.1.1Thispracticecoversuniformprocedurestodevelop,select,collect,prepare,anduseoxidized,relativelyunpolluted,aquaticnatural-matrixbed-sedimentreferencesamplesforthecollaborativetestingofc......
【中国标准分类号】:D04
【国际标准分类号】:
【页数】:4P.;A4
【正文语种】:英语
【英文标准名称】:OutlineofInvestigationforTestMethodforMeasuringtheSurfaceFlamePropagationCharacteristicsofFlooringandFloor-CoveringMaterialsIssueNumber:3;BulletinDated11/23/1999(1p)
【原文标准名称】:测量地板和地板覆盖材料表面火焰传播特性测试方法的调查大纲.发布编号:3;公布日期:1999年11月23日(1页)
【标准号】:ULSUBJECT1004BBULLETINS-2001
【标准状态】:现行
【国别】:美国
【发布日期】:2001
【实施或试行日期】:
【发布单位】:美国保险商实验所(US-UL)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:
【英文主题词】:
【摘要】:OutlineofInvestigationforTestMethodforMeasuringtheSurfaceFlamePropagationCharacteristicsofFlooringandFloor-CoveringMaterialsIssueNumber:3;BulletinDated11/23/1999(1p)
【中国标准分类号】:C82
【国际标准分类号】:
【页数】:4
【正文语种】:英语