简介：TherelationshipbetweendissolutionrateandpHisdeterminedbycarryingoutdynamicexperimentsofhedenbergiteandgrossularitedissolution.Thedissolutionreactionequationsareestablished.Thedissolutionpro-cessesoftwomineralsaresimulatedbyusingthetheoryofmulti-phaseandmulti-componentchemicalequilibrium.Theresultsbringlighttothemechanismofdissolutionprocesses.Duetoincongruentdissolutionoftwomineralswhenthedissolutionprocessesreachametastablesupersaturationcriticalpointnewmetastablemineralscanbeformedinthesystem.TheexperimentsshowedthatdissolutionofgrossulariteandhedenbergiteconsumesH~+andthenmakespHvalueofsolutionhigh.Inturn,precipitationofmetastablemineralsmakespHvaluelow.Precipitationofmetastablemineralshasacatalyticeffectfordisso-lutionofreactingmineralsinspecialtime.PrecipitationanddissolutioncarriedoutalternatelyinthesystemanditcausesperiodicoscillationofpHvalueswithreactingtime.Thisisthe

简介：<正>Polyhalite(K2SO4·MgSO4·2CaSO4·2H2O)isoneoftheinsolublepotassiummineralwhichiswidelydistributedinsulfate-typepotassium-bearingdeposit,andthetheoreticalconcentrationofK2SO4is28%.Itcanbedirectlyusedasa

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简介：Thedissolutionkineticsofvanadiumtrioxideinsulphuricacid-oxygenmediumwasexamined.Itwasdeterminedthattheconcentrationofsulphuricacidandstirringspeedabove800rmin1didnotsignificantlyaffectvanadiumextraction.Thedissolutionrateincreasedwithincreasingtemperatureandoxygenpartialpressure,butdecreasedwithincreasingparticlesize.Thedissolutionkineticswascontrolledbythechemicalreactionatthesurfacewiththeestimatedactivationenergyof43.46kJ·mol-1.Thel...

简介：在油页岩的反击过程期间形成的CaS在表面水质量上有危险影响。有水的反驳说的油页岩的相互作用由于CaS部件与硫的一个高内容产生高度碱的leachate。在与水的接触描述稳固的钙硫化物的行为的一个理论模型被开发。模型与在溶解行为看变化稳固的CaS什么时候留在答案的大小历久不渝。pH的试验性的大小和离子的集中在25点在没有氧的水里被执行吗？

简介：55%SiCp/A356(体积部分)以铜锌金焊接在把Zn-Al合金用作filler金属的空中的composites被调查。在以铜锌金焊接的过程期间，超声的颤动为结合被用于样品，进在基础材料的矩阵合金的filler金属的重要溶解发生了。当以铜锌金焊接的温度被增加，在基础材料的部分融化层的厚度增加了。原文如此，在基础材料的部分融化层的粒子在超声的行动下面被变成液体filler，有同类地分布式的加强的一张契约在团结以后被获得。体积部分原文如此，在契约的粒子能被改变以铜锌金焊接的温度改变。最大值原文如此，契约材料的粒子体积部分在500的以铜锌金焊接的温度到达了37%?????????????敷摬摥？？

简介：Understandingtheeffectsoforganicacids（OA）onthetransformationofFeandMntosurfacewaterfromtheweatheringcoalgangueisofgreatbene?ttoriskassessmentandremediationstrategiesforcontaminatedwaterandsoil.BasedontheinvestigationonsurfacewaterinthecentralcoaldistrictsoftheGuizhouProvince,18watersampleswerecollectedforheavymetalanalysis.TheresultsindicatedthatthepHvalueofsurfacewaterislow（3.11–4.92）,andFeconcentration(1.31–5.55mgL-1)andMnconcentration(1.90–5.71mgL-1)were,onaverage,10.86and34.33timesthelimitofSurfaceWaterQualityStandards,respectively.InordertoevaluatetheeffectsoftheOAonthedissolutionofFeandMnfromtheweatheringcoalgangue,columnelutionandbatchleachingexperimentswereconducted.Theresultsshowthatthelowmolecularweightoforganicacids（LMWOAs,i.e.,oxalic,tartaric,malicandcitricacids）andfulvicacidssigni?-cantlyacceleratedthedissolutionofFeandMn;inaddition,whentheconcentrationofOAreached25mmolL-1,theconcentrationsofFe,andMnwere1.14–67.08and1.11–2.32timesashighasthosein0.5mmolL-1OA,respectively.Furthermore,themigrationofFeandMnwassigni?cantlyin?uencedbythepHandEh,especiallyforFe;theionMnwasdissolvedfromtheganguemoreeasilythantheionFeinthecolumnleaching,whichwascontrarytotheresultsofbatchleaching.

简介：Potassiumchloride,Na-pyrophosphate,CuCl2,NH4-oxalate,dithionit-citrate-bicarbonate(DCB)andNa-citratesolutionswereemployedtoetractaluminum(Al)andiron(Fe)sequentiallyandseparatelyfrom15acidicsoilslocatedattheMangshanMountains,HunanProvince,China,ManyevidencesshowedthatseparatepyrophosphateextractedmainlyKCl-extractableAl,organo-AlcomplexesandsomeinorganicAlcompounds,whereasseparateCuCl2extractedKCl-extractableAlandsomeorgano-Alcomplexes,CuCl2extractedmuchlessamountsofAlthanpyrophosphatedidfromthesoils.SeparateoxalatedidnotextractallKCl-pyrophosphate-CuCl2-oxalateseuentiallyextractableAlandFe,Also,separateDCBdidnotextractallKCl-pyrophosphate-CuCl2-oxalate-DCBsequentiallyextractableAl.TheformsofAlextactedbyoxalateandDCBfromthesoilsweremajorlynoncrystalline.Theinterlayeredmaterialsof1.4-nmintergrademineralsofthesoilswereattributedmainlytohydroxyAlpolymers.

简介：Thispaperpresentsamicrostructuralcharacterizationofstandardferroniobium(FeNb)andastudyofitsdissolutioninsteel.Interrupteddissolutiontrialsatdifferenttemperatureswerecarriedoutinalaboratoryinductionfurnace.ThemicrostructureattheinterfacebetweensolidFeNbandfrozensteelwasanalyzedandcomparedwiththeoriginalFeNbparticles.TheresultsallowedclarifyingboththeFeNbdissolutionmechanismanditsincorporationkineticsatsteelmakingtemperatures.ExperimentalresultsfromthedissolutionofstandardFeNbinliquidsteelprovedthatthedissolutionratesofFeNbparticleswerehigherthanthosereportedinthepertinentliterature,wheremodelsassumethatFeNbdissolvesonlybythediffusionofsolidparticlesduetoitshighmeltingtemperatures(over1600℃).MostrecentFeNbphasediagramsandDTAanalyseshaveshownthatstandardFeNbbeginstomeltdownbelow1600℃.TheexperimentalevidencesinthisworkhaveledtotheadoptionofanewdescriptionofthedissolutionmechanismwherebystandardFeNbdissolvespredominantlybythemeltingofitseutecticzonesat1500℃to1510℃and,lateron,bythemeltingoftheprimarylathsbetween1530℃and1575℃,i.e.,belowthesteelmakingtemperaturesofaround1600℃.Basedontheseresultsandonpreviousmelting-shopexperience,thispaperrecommendsthebestpracticesfortheadditionofFeNbduringthemicroalloyedsteelssecondaryrefiningphase.

简介：AnimprovedmethodhasbeendevelopedforenrichinganddeterminingtraceIn,Pt,Sn,Co,Hg,Pb,Ni,Bi,Pd,CuandAginhigh-puritygallium.SamplewastreatedbyPDM（partialdissolutionofmatrix）withHCl（11mol/L）-HNO3（0.5mol/L）toasmallresidueofwhichGawasthenremovedbyextractionwith1mlisopropylether.TheconcentratedimpuritiesweredeterminedbyAESprocedure.Therecoveriesfortheele-mentsattherangeof0.02～0.2μgare95～103％;therelativestandarddeviationsfordeterminedimpuritiesoverarangeofn.10-7～n·10-8％are4.3～12％;thedetectionlimitofmostelementscanreachn·10-7～n·10-8％levelwiththeexceptionofHgandPt.Thismethodhasbeensuccessfullyusedtoanalyzemanysam-plessentbyfactoriesandinstitutes.

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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.

简介：Inthepresentstudy,weaimedtodeterminethequalityofdifferentbrands(Test1–Test6)ofmefenamicacid,whicharecommerciallyavailableinlocalmarketofKarachi,Pakistan.Variousqualityevaluationtests,includingweightvariation,hardness,thickness,friability,disintegration,assayanddrugrelease,werecarriedout.Resultswerefoundtobeinacceptablelimits.Moreover,releaseprofileswerecomparedusingdifferentdissolutionmedia,suchasphosphatebufferpH6.8,7.4andbiorelevantmedia(FaSSGF,FaSSIF,FeSSIFandSCoF).ReleaseprofilesatpH6.8and7.4wereevaluatedbyone--wayANOVA,model-independentandmodel--dependentmethods.ResultsofANOVAshowedthatnosignificantdifferencewasfoundamongtesterandreferencebrands(Test1–Test6).Similarly,allthebrandswerefoundtobebestfittedwithWeibullmodel.

简介：ThemetasedimentsintheChambaregionexperiencedthreephasesofdeformation:DF1,DF2andDF3.Foldedquartzveinsareco-foldedwiththeF2crenulationfolds.Theirgeometricandtectonicsignificanceisstudiedbymicrostructuresandshorteningadjacenttothediscretecrenulationcleavage,S2.Microstructuresoffoldedveinsegments,theirgeometricchangesandtruncationtocleavage(S2)aremainlyduetopressure-solutionphenomenaandtheestimatedvolumelossfromreconstructedveinsegmentsrangefrom16to25.5%,whichiscloselyrelatedtovolumedecrease(26%)calculatedfromthepolydeformedslatesofNorthWalesareas.

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