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【英文标准名称】:StandardTestMethodforVolatilityRatebyThermogravimetry
【原文标准名称】:用热重分析法测定挥发速度的标准试验方法
【标准号】:ASTME2008-2008
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【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】:E37.01
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:massloss;thermogravimetricanalysis(TGA);thermogravimetry(TG);volatility;volatilityrate;Masslosstesting;Thermogravimetricanalysis(TGA);Volatility
【摘要】:Volatilityofamaterialisnotanequilibriumthermodynamicpropertybutisacharacteristicofamaterialrelatedtoathermodynamicpropertythatisvaporpressure.Itisinfluencedbysuchfactorsassurfacearea,temperature,particlesize,andpurgegasflowrate;thatis,itisdiffusioncontrolled.Theextentofcontainmentachievedforspecimensinthistestmethodbymeansofapinholeopeningbetween0.33to0.38mmallowsformeasurementcircumstancesthatarerelativelyinsensitivetoexperimentalvariablesotherthantemperature.Decreasingtheextentofcontainmentbyuseofpinholeslargerthan0.38mmwillincreasethemagnitudeoftheobservedrateofmasslossbutwillalsoreducethemeasurementprecisionbyincreasingthesensitivitytovariationsinotherexperimentalvariables.Resultsobtainedbythistestmethodarenotstrictlyequivalenttothoseexperiencedinprocessingorhandlingconditionsbutmaybeusedtorankmaterialsfortheirvolatilityinsuchcircumstances.Therefore,thevolatilityratesdeterminedbythistestmethodshouldbeconsideredasindexvaluesonly.Thevolatilityratemaybeusedtoestimatesuchquantifiablevaluesasdryingintervalortheextentofvolatilereleasefromaprocess.DESIG:E228108a^TITLE:StandardPracticeforProcessandMeasurementCapabilityIndices^SIGNUSE:ProcessCapability8212;Processcapabilitycanbedefinedasthenaturalorinherentbehaviorofastableprocessthatisinastateofstatisticalcontrol(1).Ax201C;stateofstatisticalcontrolx201D;isachievedwhentheprocessexhibitsnodetectablepatternsortrends,suchthatthevariationseeninthedataisbelievedtoberandomandinherenttotheprocess.Processcapabilityislinkedtotheuseofcontrolchartsandthestateofstatisticalcontrol.Aprocessmustbestudiedtoevaluateitsstateofcontrolbeforeevaluatingprocesscapability.ProcessControl8212;Therearemanywaystoimplementcontrolcharts,butthemostpopularchoiceistoachieveastateofstatisticalcontrolfortheprocessunderstudy.Specialcausesareidentifiedbyasetofrulesbasedonprobabilitytheory.Theprocessisinvestigatedwheneverthechartsignalstheoccurrenceofspecialcauses.Takingappropriateactionstoeliminateidentifiedspecialcausesandpreventingtheirreappearancewillultimatelyobtainastateofstatisticalcontrol.Inthisstate,aminimumlevelofvariationmaybereached,whichisreferredtoascommoncauseorinherentvariation.Forthepurposeofthisstandard,thisvariationisameasureoftheuniformityofprocessoutput,typicallyaproductcharacteristic.ProcessCapabilityIndices8212;Thebehaviorofaprocess(asrelatedtoinherentvariability)inthestateofstatisticalcontrolisusedtodescribeitscapability.Tocompareaprocesswithcustomerrequirements(orspecifications),itiscommonpracticetothinkofcapabilityintermsoftheproportionoftheprocessoutputthatiswithinproductspecificationsortolerances.Themetricofthisproportionisthepercentageoftheprocessspreadusedupbythespecification.Thiscomparisonbecomestheessenceofallprocesscapabilitymeasures.Themannerinwhichthesemeasuresarecalculateddefinesthedifferenttypesofcapabilityindicesandtheiruse.Twoprocesscapabilityindicesaredefinedin5.2and5.3.Inpractice,theseindicesareusedtodriveprocessimprovementthroughcontinuousimprovementefforts.Theseindicesmaybeusedtoidentifytheneedformanagementactionsrequiredtoreducecommoncausevariation,compareproductsfromdifferentsources,andtocompareprocesse......
【中国标准分类号】:A42
【国际标准分类号】:71_040_50
【页数】:8P.;A4
【正文语种】:英语