QJ 2498.12-1993 模件组合式控制台结构及尺寸系列 转角件

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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
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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
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【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