JJG 2059-1990 电导计量器具检定系统

作者:标准资料网 时间:2024-05-08 16:38:27   浏览:8148   来源:标准资料网
下载地址: 点击此处下载
基本信息
标准名称:电导计量器具检定系统
英文名称:the Conductometric Measuring Instruments
中标分类: 综合 >> 计量 >> 化学计量
发布部门:国家技术监督局
发布日期:1990-05-05
实施日期:1990-09-01
首发日期:
作废日期:
起草单位:国家标准物质研究中心
起草人:侯传嘉
出版社:中国计量出版社
出版日期:1990-09-01
页数:7页
适用范围

本检定系统适用于检定电导计量器具的检定程序。本检定系统规定了电解质电导率国家计量基准的用途,基准包括的全套基本计量器具,基准的基本计量学参数以及将电导单位量值由国家基准通过计量标准器具传递到工作计量器具的传递程序,并指明其不确定度和基本检定方法。

前言

没有内容

目录

没有内容

引用标准

没有内容

所属分类: 综合 计量 化学计量
下载地址: 点击此处下载
【英文标准名称】:Ambientair-Determinationofasbestosfibres-Indirect-transfertransmissionelectronmicroscopymethod
【原文标准名称】:环境空气.石棉纤维的测定.间接传递电子显微镜法
【标准号】:BSISO13794-1999
【标准状态】:现行
【国别】:英国
【发布日期】:1999-11-15
【实施或试行日期】:1999-11-15
【发布单位】:英国标准学会(BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:报告;试样;宽度;工作范围;文献索引;识别方法;试验设备;试验条件;显微分析;干扰(化学);性能;浓度(化学);形状;角闪石;长度;泊松分布;试样制备;高宽比;纤维;分类系统;颗粒空气污染物;采样设备;有毒物质;电子显微镜;计数;方程;矿物纤维;石棉;尺寸测量;灰分测定;抽样方法;空气污染;置信限;含量测定;校正;空气;密度;灵敏度;过滤;数学计算
【英文主题词】:Airpollution;Airquality;Ambientair;Asbestos;Asbestosdust;Definition;Definitions;Determinationofcontent;Microscopicanalysis
【摘要】:1SubstancedeterminedThisInternationalStandardspecifiesareferencemethodusingtransmissionelectronmicroscopy(TEM)fordeterminationoftheconcentrationofasbestosstructuresinambientatmospheres.Thespecimenpreparationprocedureincorporatesashinganddispersionofthecollectedparticulate,sothatallasbestosismeasured,includingtheasbestosoriginallyincorporatedinparticleaggregatesorparticlesofcompositematerials.Thelengths,widthsandaspectratiosoftheasbestosfibresandbundlesaremeasured,andthese,togetherwiththedensityofthetypeofasbestos,alsoallowthetotalmassconcentrationofairborneasbestostobecalculated.Themethodallowsdeterminationofthetype(s)ofasbestosfibrepresent.Themethodcannotdiscriminatebetweenindividualfibresoftheasbestosandnon-asbestosanaloguesofthesameamphibolemineral.2TypeofsampleThemethodisdefinedforpolycarbonatecapillary-porefiltersorcelluloseester(eithermixedestersofcelluloseorcellulosenitrate)filtersthroughwhichaknownvolumeofairhasbeendrawn.Themethodissuitablefordeterminationofasbestosinbothexteriorandbuildingatmospheres.3RangeTheupperlimitfortherangeofconcentrationthatcanbemeasuredontheanalyticalfilteris7000structures/mm.Thelowerlimitoftherangethatcanbemeasuredontheanalyticalfiltercorrespondstodetectionof2,99structuresintheareaofspecimenexamined.Theairconcentrationsrepresentedbythesevaluesareafunctionofthevolumeofairsampledandthedegreeofdilutionorconcentrationselectedduringthespecimenpreparationprocedures.Themethodisparticularlyapplicableformeasurementsinareaswithhighsuspended-particulateconcentrations(exceeding10μg/m),orwheredetectionandidentificationofasbestosfibresarelikelytobepreventedorhinderedbyothertypesofparticulateindirect-transferTEMpreparations.Intheory,thereisnolowerlimittothedimensionsofasbestosfibreswhichcanbedetected.Inpractice,microscopistsvaryintheirabilitytodetectverysmallasbestosfibres.Therefore,aminimumlengthof0,5urnhasbeendefinedastheshortestfibretobeincorporatedinthereportedresults.4LimitofdetectionThelimitofdetectiontheoreticallycanbeloweredindefinitelybyfiltrationofprogressivelylargervolumesofair,concentratingthesampleduringspecimenpreparation,andbyextendingtheexaminationofthespecimensintheelectronmicroscope.Inpractice,thelowestachievablelimitofdetectionforaparticularareaofTEMspecimenexaminediscontrolledbythetotalsuspendedparticulateconcentrationremainingaftertheashingandaqueousdispersalsteps,andthisdependsonthechemicalnatureofthesuspendedparticulate.Fortotalsuspendedparticulateconcentrationsofapproximately10μg/m,correspondingtoclean,ruralatmospheres,andassumingfiltrationof4000litresofair,ananalyticalsensitivityof0,5structure/litrecanbeobtained,equivalenttoalimitofdetectionof1,8structures/litre,ifanareaof0,195mmoftheTEMspecimensisexamined.LowerlimitsofdetectioncanbeachievedbyincreasingtheareaoftheTEMspecimenthatisexamined,orbyconcentrationofthesampleduringspecimenpreparation.Inordertoachievelowerlimitsofdetectionforfibresandbundleslongerthan5μm,andforPCM-equivalentfibres,lowermagnificationsarespecifiedwhichpermitmorerapidexaminationoflargerareasoftheTEMspecimenswhentheexaminationislimitedtothesedimensionsoffibre.
【中国标准分类号】:Z15
【国际标准分类号】:13_040_20
【页数】:74P.;A4
【正文语种】:英语


【英文标准名称】:Steelwireropes.Methodfordeterminationofbreakingload.
【原文标准名称】:钢丝绳.断裂载荷的测定方法
【标准号】:NFA47-210-1986
【标准状态】:作废
【国别】:法国
【发布日期】:1986-10-01
【实施或试行日期】:1986-10-05
【发布单位】:法国标准化协会(AFNOR)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:试验;试验;金属丝绳;钢丝绳;断裂荷载;抗拉试验
【英文主题词】:Breakingload;Steel-wireropes;Tensiletesting;Testing;Tests;Wireropes
【摘要】:
【中国标准分类号】:H49
【国际标准分类号】:77_140_65
【页数】:3P;A4
【正文语种】:其他