es4045314

es4045314ComparativeExaminationofEffectsofBindingofDifferentMetalsonChromophoresofDissolvedOrganicMatterMingquanYan*,†andGregoryV.Korshin‡†TheKeyLaboratoryofWaterandSedimentSciences,MinistryofEducation,DepartmentofEnvironmentalEngineering,PekingUniversity,Beijing100871,People’sRepublicofChina‡DepartmentofCivilandEnvironmentalEngineering,UniversityofWashington,Box352700,Seattle,Washington98195-2700,UnitedStates*SSupportingInformationABSTRACT:Thisstudyquantifiedthebindingofdissolvedorganicmatter(DOM)fromSuwanneeRiverwithninemetals,Ca(II),Mg(II),Fe(III),Al(III),Cu(II),Cd(II),Cr(III),Eu(III),andTh(IV),usingadifferentialabsorbanceapproach.ThedifferentialspectraofDOMwerecloselyfittedwithsixGaussianbandsthatwerepresentforallofthemetalsatvaryingpHvalues.Theirmaximawerelocatedatca.200,240,276,316,385,and547nm(denotedasA0,A1,A2,A3,A4,andA5,respectively).TherelativecontributionsandsignsoftheGaussianbandsweremetal-specificandcorrelatedtosomedegreewiththecovalent-bondingindexoftheionsandapplicablec