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简介：Gneiss-distilledwaterinteractionatroomtemperaturewasinvestigatedwithbatch-reactorstostudywater-rockreactionandgeochemicalevolutionoftheaqueousphasewithtime.Theionconcentrationsinwaterwerecontrollednotonlybythedissolutionofprimaryminerals,butalsobytheprecipitationofsecondaryminerals.Thedecreasingfractionsizesofgneisscouldfavordissolutionandprecipitationsimultaneously.Ca2+andK+werethemajorcations,andHCO3-wasthemajoranioninwater.AlltheionsexceptCa2+increasedinconcentrationwithtime.TheCa2+releasefromtherocktotheaqueousphasewasinitiallymuchfasterthanthereleaseofK+,Na+andMg2+.Butafterabout5-24hours,theCa2+concentrationsinwaterdecreasedveryslowlywithtimeandbecamerelativelystable.Duringtheexperiment,thewatervariedfromtheCa-(K)-HCO3-typewatertotheK-Ca-HCO3-typewater,andthentotheK(Ca,Na)-HCO3-typewater.Thewater-gneissinteractionwasdominatedbythedissolutionofKfeldsparinthesolution.Theremainingsecondarymineralsweremainlykaolinite,illiteandK(Mg)-mica.

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简介：Oxygenisotopefractionationwasexperimentallystudiedinthequartz-wolframite-watersystemfrom200to420℃.ThestartingwolframitewassynthexizedinaqueoussolutionsofNa2WOR·2H2O+FeCl2·4H2OorMnCl2·4H2O.Thestartingsolutionsrangeinsalinityfrom0to10equivalentwt.%NaCl.Experimentswereconductedinagold-linedstainlesssteelautoclave,withfillingdegreesofabout50%.Theresultsshowednosignificantdifferenceindquilibriumisotopefractionationbetweenwaterandwolframite,ferberiteandhuebneriteatthesametemperature(310℃）.Theequilibriumoxygenisotopefractionationfactorsofwolframiteandwatertendtobeequalwithincreasingtemperatureabove370℃.buttoincreasesignificantlywithdecreasingtemperaturebelow370℃.

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简介：Inordertobetterunderstandthecompositionalandstructuralcomplexityofdissolvedorganicmatter（DOM）macromoleculesandprovidemechanisticinformationonthebindingofhydrophobicorganiccontaminants（HOCs）toDOM,wefractionatedlargeamountsoflakewaterintothreehydrophobicDOM-fractions.Thevariationofthepartitioningcoef?cients(KDOC)ofpyreneatdifferentpHlevelswasexaminedby?orescencequenchingtitration.Resultsshowthat,relativetothemorepolaracidicDOM-fractions,thehydrophobicneutralfractionexhibitsahighersorptionabilitytopyrene.Generally,thesorptionofpyrenetothethreehydrophobicfractionsisstronglypH-dependent.TheKDOCvaluesofpyrenegenerallyincreasewithdecreasingpHlevels,whichisespeciallyobviousinthesorptionofpyrenetothefulvicacidfractions,suggestingthatthebindingiscontrolledbyhydrophobicinteractions.Themechanismsunderlyingthebindingofpyrenetothehydrophobicfractionswerealsodiscussed.Ourdataarebene?cialtofurtherunderstandingthebindingofHOCstoDOMandhowithasbeenaffected,whichmayresultinmoreaccuratepredictionsofKDOC.