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1、Ultraviolet/VisibleSpectroscopyFifthgroupSpeaker:GaoXianzheUVradiationistheelectromagneticradiationofawavelengthshorterthanthatofvisiblelight,butlongerthanthatofx-rays.ThetypicalrangeofUVwavelengthis10-400nm.UVRadiationIndailylife,varioussolutionsarepresentedwithdifferentcolors,becauseitisrelate
2、dtotheselectiveabsorptionoflight.Whenabeamoflightismadeupofasolutionbyacertainproportion,somewave-lengthsoflightareabsorbedbythesolution,whiletheotherwavelengthsoflightarenotabsorbedthroughthesolution.Whenthelightisvisiblethroughthelightpacketcontainingthevisiblewavelengthrange,itcanbeseenbytheh
3、umaneye,thecolorofthesolutionisdeterminedbythewavelengthofthelight.UVAbsorptionUV/VisSpectroscopyDefinition:It’stheanalysismethodswithanalysis,determinationandinferenceofmaterialcomposition,contentandstructurebyusingtheuv-visspectraandthedegreeofabsorptionwhichproducedbymaterialmolecules,orionso
4、ntheabsorptionofultravioletandvisiblelight.Features:Highsensitivity,highaccuracy,goodselectivity,easytooperate,fastanalysisspeed,wideapplicationrange.AbsorptionCurveUsingdifferentwavelengthsoflightthroughasolutionofconstantconcentrationandthicknesstomeasuretheabsorptiondegreebytestingoneachwavel
5、engthlight(absorbance),andthenmakethewavelengthastheabscissaandtheabsorbanceastheordinatetomapacurve.Thematerialabsorptioncapacityofdifferentwavelengthcanbedescribedbythecurve,calledabsorptioncurveorabsorptionspectra.Thesameconcentrationofthesolutionundertesthasdifferentabsorbancetodifferentwave
6、lengthsoflight.Forthesametestsolution,thegreatertheconcentration,thegreatertheabsorbance.Forthesamematerial,nomatterwhattheconcentrationis,thewavelengthconnectedwiththemaximumabsorptionpeak(themaximumabsorptionwavelengthλmax)isthesame,andtheshapeofthecurveisalsothesame.Accordingtotheanalysisofab
7、sorptioncurve:Lambert-BeerLawResearchshows,theabsorptiondegreeofcolorsolutiontomonochromaticlightisrelatedtotheconcentrationofsolutionandthethicknessofliquidlayer.ThisisthefamousLambert-Beerlaw,itisthebasisofcoloranalysis.Wh
