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【英文标准名称】:StandardGuideforForensicExaminationofNon-ReactiveDyesinTextileFibersbyThin-LayerChromatography
【原文标准名称】:司法鉴定用薄层色谱法对纺织品纤维中非活性染料检测指南
【标准号】:ASTME2227-2002(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:2002
【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】:E30.01
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:
【英文主题词】:fibers;forensicscience;thin-layerchromatography;Fibercolorant;Fibers;Forensicinvestigation/analysis;Nonreactivedyes;Singlefibercomparison;Textilefiber(forensic)analysis;Thinlayerchromatography(TLC)
【摘要】:ForensicanalysisoffibercolorantsusingTLCshouldbeconsideredforsinglefibercomparisonsonlywhenitisnotpossibletodiscriminatebetweenthefibersofinterestusingothertechniques,suchascomparisonmicroscopy(brightfieldandfluorescence)andmicrospectrophotometryinthevisiblerange.TheextractionprocedurescarriedoutpriortoTLCanalysiscanprovideusefulinformationaboutdyeclassification.TLCcanprovideusefulqualitativeinformationaboutdyecomponents.Similarcolorsmadeupofdifferentdyecomponentscanbedifferentiatedusingthistechnique.TheapplicationofTLCmayservetodiscriminatebetweenfibers,oritmayconfirmtheirsimilarity.TLCmaybeprohibitivelydifficultorundesirableinsomecircumstances.Shortlengthsoffibersorpalecoloredfibersmaynothaveanadequateconcentrationofcolorantpresenttobeexamined,dyeextractionfromsomefibersmaybeimpossible.Thedesiretopreserveevidenceforpossibleanalysisbyanotherexaminermayprecluderemovingthecolorforanalysis.Dyefromtheknownmaterialshouldfirstbecharacterizedandeluentsystemsevaluatedtoachieveoptimumseparationoftheextract.Dyeisthenextractedfromsingleknownandquestionedfibers,usinganequivalentamountofmaterial.ThedevelopmentofeachindividualTLCplatewillshowsomevariabilityasaresultofthecoatingandconditioningoftheplate,solventcondition,andtemperature.ItisimportanttoevaluatetheperformanceofeachTLCplatebyspottingknownmaterialsalongwiththequestionedsamples.SeeRef(16).ExamplesforthepreparationofStandarddyemixturesaregiveninAppendixX1.1.1MetamericcolorationoffiberscanbedetectedusingUV/visiblespectrophotometry.Ifspectrophotometryisrestrictedtothevisiblespectralrangeonly,differencesindyecomponentsmayremainundetected.Onemethodofdetectingadditionalcomponentsistousethin-layerchromatography(TLC).TLCisaninexpensive,simple,well-documentedtechniquethat,undercertainconditions,canbeusedtocomplementtheuseofvisiblespectroscopyincomparisonsoffibercolorants.Theprincipleofthemethodisthatthedyecomponentsareseparatedbytheirdifferentialmigrationcausedbyamobilephaseflowingthroughaporous,adsorptivemedium.1.2ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.
【中国标准分类号】:W55
【国际标准分类号】:71_040_50
【页数】:6P.;A4
【正文语种】:英语