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【英文标准名称】:StandardPracticeforCompressionMoldingThermoplasticMaterialsintoTestSpecimens,Plaques,orSheets
【原文标准名称】:试样、板或薄板中热塑性材料压缩模塑的标准实施规程
【标准号】:ASTMD4703-2007
【标准状态】:现行
【国别】:
【发布日期】:2007
【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】:D20.09
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:压缩模塑材料;塑料;聚乙烯;制备;工艺;试件;试样;热塑性聚合物
【英文主题词】:acrylonitrile-butadiene-styrene(ABS);chlorinatedpoly(vinylchloride)(CPVC);compressionmolding;polyethylene(PE);poly(vinylchloride)(PVC);styrene-butadiene;testspecimenpreparation;thermoplastics
【摘要】:Themethodsbywhichsamplematerialsarepreparedandmoldedinfluencethemechanicalpropertiesofthespecimen.Unlikeinjectionmolding,theobjectiveofcompressionmoldingistoproducetestspecimensorsheetsthatarebothhomogeneousandisotropic.Moldedspecimensmaybemadefrompowderorpelletssuchasarereceiveddirectlyfromamaterialmanufacturer,particlesproducedinarecyclerecoveryoperation,orfromamilledpreformorsheetpreparedonatwo-rollmill.Thepowder,pellets,particles,preform,orsheetaremeltedandmoldedinamolddesignedtoproduceafinishedspecimenofagivengeometry,size,andthickness,ormeltedandmoldedintheformofasmoothplaqueorsheetofuniformthicknessfromwhichdesiredspecimensarecut,punched,ormachined.Workingacompoundonatwo-rollmillpriortomoldingwilldisperseanddistributethecompoundadditivesinamannerthatwillaffectthephysicalpropertiesofthecompound.Theneedformillingasamplepriortocompressionmoldingmaybedeterminedbyreferencetotherelevantmaterialspecificationorthematerialmanufacturer.Itisimportanttotreatdifferentsamplesofthesametypeofmaterialinthesameway:ifmillingwasdonepriortomoldingonamaterialwhichistobeusedasastandardforcomparison,allnewmaterialstobetestedagainstthispracticeshouldbepreparedandmoldedinasimilarmanner.Theapparatusandexactconditionsrequiredtoprepareadequatespecimensmayvaryforeachplasticmaterial.ApparatusandprocedureswhichshouldbesatisfactoryformoldingmanydifferentplasticmaterialsaregiveninthispracticeinSections5and6.TheapparatusandprocedureswhichhavebeenfoundsatisfactoryformoldingcertainspecificmaterialsaregivenintheAppendix.Inanycase,theapparatusandprocedurestobeusedinproducingcompression-moldedspecimensofagivenmaterialmaybeobtainedbyreferencetotherelevantmaterialspecificationandshouldbeagreeduponbetweenthepurchaserandthesupplier.1.1Thispracticecoversthecompressionmoldingofthermoplasticgranulesandmilledstockforthepreparationoftestspecimens.1.2Whileconditionsforcertainmaterialsaregiven,theprimarysourceofspecificconditionsshallbethematerialspecificationstandardsforeachtypeofmaterial.1.3ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninbracketsareforinformationonly.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.Note1ThemainbodyofthispracticeisequivalenttoISO293-1986.andISO293-1986differinsomedetails;however,specimenspreparedusing,ProcedureAshouldbeequivalenttothosepreparedusingISO293-1986,CoolingMethodD.Specimenspreparedusing,ProcedureCshouldbeequivalenttothosepreparedusingISO293-1986,CoolingMethodB.However,duetothegreatercoolingratetolerancesoftheISOstandard,specimenspreparedinaccordancewithISOCoolingMethodBmaynotbeequivalentto,ProcedureC.
【中国标准分类号】:G33
【国际标准分类号】:
【页数】:12P.;A4
【正文语种】:


【英文标准名称】:StandardforminimumperformancecharacteristicsofIEEE802.20terminalsandbasestations/accessnodes
【原文标准名称】:IEEE802.20终端和基站/存取节点的最小性能特性标准
【标准号】:IEEE802.20.3-2010
【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】:美国电气电子工程师学会(US-IEEE)
【起草单位】:IEEE
【标准类型】:()
【标准水平】:()
【中文主题词】:通路;空中接口;宽带;宽带网络;宽带系统;数据链层;数据传送;定义;信息技术;接口(数据处理);LAN;局域网;多路存取计算机;MAN;测量;测量技术;介质;媒体访问控制;城域网;网络;物理层;协议履行一致性声明;终端;试验;无线的;无线通信业务
【英文主题词】:Access;Airinterfaces;Broadband;Broadbandnetwork;Broadbandsystems;Datalinklayers;Datatransfer;Definitions;Informationtechnology;Interfaces(dataprocessing);LAN;Localareanetworks;MAC;MAN;Measurement;Measuringtechniques;Media;Mediumaccesscontrol;Metropolitanareanetworks;Network;Physicallayers;Protocolimplementationconformancestatement;Terminals;Testing;Wireless;Wirelesscommunicationservices
【摘要】:
【中国标准分类号】:L78
【国际标准分类号】:35_110
【页数】:77P;A4
【正文语种】:英语