硼氢化物还原对CDOM和腐殖质光学性质的影响

硼氢化物还原对CDOM和腐殖质光学性质的影响OpticalPropertiesofHumicSubstancesandCDOM:EffectsofBorohydrideReductionJIAHAIMA,†,§ROSSANADELVECCHIO,*,‡KELLIS.GOLANOSKI,†ERINS.BOYLE,†,⊥ANDNEILV.BLOUGH*,†DepartmentofChemistryandBiochemistry,UniversityofMaryland,CollegePark,Maryland20742,andEarthSystemScienceInterdisciplinaryCenter(ESSIC),UniversityofMaryland,CollegePark,Maryland20740ReceivedMarch18,2010.RevisedmanuscriptreceivedMay30,2010.AcceptedJune2,2010.TreatmentofSuwaneeRiverhumic(SRHA)andfulvic(SRFA)acids,acommerciallignin(LAC),andaseriesofsolidphaseextracts(C18)fromtheMiddleAtlanticBight(MABextracts)withsodiumborohydride(NaBH4),aselectivereductantofcarbonyl-containingcompoundsincludingquinonesandaromaticketones,producesapreferentiallossofvisibleabsorption(g50%forSRFA)andsubstantiallyenhanced,blue-shiftedfluorescenceemission(2-to3-foldincrease).Comparisonoftheresultswiththoseobtainedfromaseriesofmodelquinonesandhydroquinonesdemonstratesthatthesespectralchangescannotbeassigneddirectlytotheabsorptionandemiss