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【英文标准名称】:StandardTestMethodforEstimatingStrayRadiantPowerRatioofDispersiveSpectrophotometersbytheOpaqueFilterMethod
【原文标准名称】:用不透明滤光器评估色散分光光度计杂散辐射功率的标准试验方法
【标准号】:ASTME387-2004(2009)
【标准状态】:现行
【国别】:美国
【发布日期】:2004
【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】:E13.01
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:molecularspectroscopy;spectrophotometry;SRP;SRPR;straylight;strayradiantpower;strayradiantpowerratio;Energyanalysis;Energydeposition;Radiantenergy;Spectrophotometry--absorption
【摘要】:Strayradiantpowercanbeasignificantsourceoferrorinspectrophotometricmeasurements.SRPusuallyincreaseswiththepassageoftime;therefore,testingshouldbeperformedperiodically.Moreover,theSRPRtestisanexcellentindicatoroftheoverallconditionofaspectrophotometer.Acontrol-chartrecordoftheresultsofroutinelyperformedSRPRtestscanbeausefulindicatorofneedforcorrectiveactionor,atleast,ofthechangingreliabilityofcriticalmeasurements.Thistestmethodprovidesameansofdeterminingthestrayradiantpowerratioofaspectrophotometeratselectedwavelengthsinaspectralrange,asdeterminedbytheSRPfilterused,therebyrevealingthosewavelengthregionswheresignificantphotometricerrorsmightoccur.Itdoesnotprovideameansofcalculatingcorrectionstoindicatedabsorbance(ortransmittance)values.Thetestmethodmustbeusedwithcareandunderstanding,aserroneousresultscanoccur,especiallywithrespecttosomemoderngratinginstrumentsthatincorporatemoderatelynarrowbandpassSRP-blockingfilters.Thistestmethoddoesnotprovideabasisforcomparingtheperformanceofdifferentspectrophotometers.Note88212;Kaye(3)discussescorrectionmethodsofmeasuredtransmittances(absorbances)thatsometimescanbeusedifsufficientinformationonthepropertiesandperformanceoftheinstrumentcanbeacquired.SeealsoA1.2.5.Thistestmethoddescribestheperformanceofaspectrophotometerintermsofthespecifictestparametersused.Whenananalyticalsampleismeasured,absorptionbythesampleofradiationoutsideofthenominalbandpassattheanalyticalwavelengthcancauseaphotometricerror,underestimatingthetransmittanceoroverestimatingtheabsorbance,andcorrespondinglyunderestimatingtheSRPR.TheSRPRindicatedbythistestmethodusingSRPfiltersisalmostalwaysanunderestimationofthetruevalue(see1.3).Avaluecitedinamanufacturerx2019;sliteraturerepresentstheperformanceofanewinstrument,testedexactlyinaccordancewiththemanufacturerx2019;sspecification.Theimplicationisthatthemanufacturerx2019;sstatedSRPRcanserveasabenchmarkforfutureperformance,providedthattheuserperformsthemanufacturerx2019;sspecifiedtest.Itisrecommendedthatuserstestnewinstrumentspromptly,therebyestablishingacomparativebenchmarkintermsoftheirowntestingfacilities.Thesolutionfilterratiomethod(4.3)isaconvenientmethodforcontrol-chartingSRPR.Mielenz,etal.,(4)showthatitsresultstendtocorrelatewellwiththoseofthespecifiedwavelengthmethod,butforcriticalcomparisonwiththemanufacturerx2019;sspecification,themethodusedbythemanufacturermustbeused.BecausesomeinstrumentsreduceSRPbyincorporatingmoderatelynarrowbandpassSRP-blockingfiltersthatarechangedasthewavelengthrangeisscanned,itispossibleforSRPRdeterminationstobehighlyinaccurateifthecutoffwavelengthoftheSRPfilterfallstooclosetotheabsorptionedgeofaninstrumentx2019;sSRP-reducingfilter(3).1.1Strayradiantpower(SRP)canbeasignificantsourceoferrorinspectrophotometricmeasurements,andthedangerthatsucherrorexistsisenhancedbecauseitspresenceoftenisnotsuspected(1-4).Thistestmethodaffordsanestimateoftherelativeradiantpower,thatis,theStrayRadiantPowerRatio(SRPR),atwavelengthsremotefromthoseofthenominalbandpasstransmittedthroughthemonochromatorofanabsorptionspectrophotometer.Test-fil......
【中国标准分类号】:N33
【国际标准分类号】:
【页数】:11P.;A4
【正文语种】:英语