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【英文标准名称】:StandardPracticeforPreparationandUseofanIce-PointBathasaReferenceTemperature
【原文标准名称】:作为参考温度制备和使用的冰点浴的标准实施规程
【标准号】:ASTME563-2008
【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】:E20.07
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:fixed-pointtemperaturereferences;icebath;icepoint;ITS-90;watertriplepoint;Freezing-pointmeasuringequipment;Ice-pointreferencebaths;Referencebaths
【摘要】:ThispracticeisadequateforusewithotherASTMstandardsthatspecifytheicepointasareference.Itisalsointendedtobeadequateformostotherice-pointreferencepurposes.Theicepointisacommonpracticalindustrialreferencepointofthermometry.Theicepointisrelativelysimpletorealizeandprovidesareadilyavailablenaturalfixed-pointreferencetemperature.UseinResistanceThermometry:Theicepointwasadefiningfixedpointonpracticaltemperaturescalespriorto1960.TheITS-90definesW(T90)=R(T90)/R(273.16K),themeasuredresistanceratioofaStandardPlatinumResistanceThermometer(SPRT),inreferencetothewatertriplepoint,nottheicepoint(1).Inmanyinstances,wherethewatertriplepointisnotavailable,orwhentheaccuracyobtainablewiththewatertriplepointisnotrequired,referencetoaproperlyestablishedandmaintainedice-pointreferenceisused.Forindustrial-qualityresistancethermometers,theresistancevalueisdeterminedfor0x00B0;C,andanuncertaintythatisappropriateforthequalityoftheice-pointrealizationisassigned.UseinThermoelectricThermometry:Inthermoelectricthermometry,theicepointisordinarilyusedasthereferencetemperature(2).Adequatethermoelectricreferencerequiresthatthermocouplejunctionsbewell-coupledthermallytothebath,electricallyisolatedfromeachotherandfromthebath,andadequatelyimmersedtoavoidperturbingthereference-junctiontemperaturesbyradiationandlongitudinalconductionofheatalongthethermoelements(3and4).UseinLiquid-in-GlassThermometry:Inliquid-in-glassthermometry,theicepointisordinarilyusedasthereferencetemperature(6).Theperiodicrecalibrationofaliquid-in-glassthermometerattheicepointprovidesareliableindicationoftheeffectofgradualrelaxationofresidualmechanicalstrainsintheglassthathaveasignificanteffectonthevolumeofthebulb(6).1.1Thispracticecoversamethodofpreparing,maintaining,andusingatemperaturereferencebathofamixtureofshavediceandwater,saturatedwithairatapressureof101325Pa(1atm).1.2AnindustrialpracticeforrelatingvaluesreferencedtotheicepointandtothewatertriplepointontheITS-90isincluded.1.3Methodstopromoteuniformityofbathtemperaturebymechanicalstirringoragitationarenotdescribedindetail.1.4Methodsofapproximatingtheicepoint,asbythermostatically-controlledrefrigeration,arenotcoveredbythispractice.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:N61
【国际标准分类号】:71_040_20
【页数】:4P.;A4
【正文语种】:英语