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亚硫酸盐纳米束状io

suc-supply(sa)是一个非常有价值的企业。在这一过程中,可以找到接受手术的微标签(pbs),这是微标签。以及直接插入到母生果皮中的微囊。这是一个非常抽象的过程。supply动物、谋杀、精细动物和微囊。这是一个分类账的过程。母面包,马尾辫,红棕色头发,还有几个小麦粉。这是一个简单的带有预算的微囊。总之,这是一个由食品部门提出的计划。这是一个缓慢的发射文件。Titaniumdioxide(TiO2)isoneofthemostwidelyusedandpromisingmaterialsinelectrocatalyticapplicationduetoitsredoxselectivity,highstability,andeasypreparation.TheadvantagesofTiO2cathodeoverconventionalcathodeshavebeendiscussed.TheeffectofvariousoperatingandprocessparametersattitaniumcathodeonelectrolyticreductionofMAtoSAhasbeenstudied.ReductionofMAatTi/ceramicTiO2undergalvanostaticandcyclicvoltametricconditionshasbeenexamined.ThethermallycoatedTi/TiO2cathodehasbeenfoundtobeveryusefulintheelectrochemicalprocessforthepreparationofSA.Recently,Chuetal.reportasol-gelmethodtopreparenanocrystallineTiO2modifiedcathodeswhichexhibitexcellentperformanceforelectrochemicalreductionofMA.ThepresentpaperreportsanovelandsimplemethodofpreparationofbunchystructureTiO2filmbyanodizationinamixtureofMAandH2SO4solution.Theas-anodizedTiO2filmelectrodeisusedforelectrocatalyticreductionofMAtoSAintheoriginalsolution.Theeffectsofcurrentdensityandin-situactivationfortheas-anodizedTiO2electrodebygalvaniccyclesontheproductyieldandcurrentefficiencyhavebeeninvestigated.1母乳喂养1.1创建ctrogecization和相关elica是构建保护行道环境的和中小企业的社会责任网络,..3—SamplepreparationTitaniumsheet(99.9%purity,Baoji3XMetal,China)withathicknessof0.4mmwascleanedbysonicatingitsuccessivelyinacetone(reagentgrade)anddeionized(DI)waterfor10mineach,followedbydryinginanairstream.ElectrochemicalanodizationofTisheetwascarriedoutwithaDCpowersupply(SKD-150V10A,SAKO,China)usingaconventionalthree-electrodesystem.AnodicfilmsweregrownontheTisheet(1.0cm2)withaplatinumsheetascounterelectrodeandasaturatedcalomelelectrode(SCE)asreferenceelectrode.Allconstantvoltageanodizationwasconductedinanelectricwaterbathformaintaining50℃andanappliedvoltageof20V.Theelectrolyte(preparedfromreagentgradechemicalsandDIwater)wasamixtureof0.5mol·L-1H2SO4+1mol·L-1MA.Afterthetreatment,theasanodizedsampleswereatfirsthandusedtothestudyofcyclicvoltammetryandgalvanostaticelectrolysis.1.2x-n-roetrace-scntagitysact/sartrace-sqie-sque-sque-sque-roeting标准scntag/kq-packs-scntagxtra/kh-packs-k-sa1radiffrationmotisque-sque-roincicienThemorphologywasconfirmedbymeansofatomicforcemicroscope(AFM,SPA400,SeikoInstrumentsInc.,Japan)withconventionalscansetting(512pointsperline,1Hz).Thecrystallinephaseandstructurewereanalyzedusinghigh-powerX-raydiffraction(ThermoARLSCNTAGX′TRA)withCuKα1radiationsourceat45kVand40mA.TheXRDpatternswererecordedwithastepsizeof0.04°from15°to80°.1.3udivicdgoCyclicvoltammetricmeasurementswerecarriedoutonCHI660Bworkstation(CHI,USA)inathree-electrodeundividedglasscell.Afterelectrochemicalanodization,thesamplewasstudiedintheoriginalposition.Alltheexperimentswereperformedataconstanttemperatureof50℃.Theexperimentalsolutionwasdeaeratedusingpurenitrogen.Cyclicvoltammogramswererecordedatasweeprateof50mV·s-1.1.4as/el果第so阶段Firstly,electrochemicalanodizationofa9cm2areaofTisheetwascarriedoutinamixtureof0.5mol·L-1H2SO4+1mol·L-1MAandthengalvanostaticelectrolysisexperimentswereinsituperformedwiththeas-anoidzedsampleascathodeanda9cm2areaofDSA(dimensionallystableanode)asanodeinalaboratory-made,undividedH-typeglasscell.Thesolutionwasstirredusingamagneticstirrer.Currentdensityintherangeof3-7A·dm-2andtemperatureof50℃wereemployed.Aftertheas-anodizedTiO2electrodeisusedtoelectrolysisascathodefor1h,thepolarityofthecellisreversedandanotheranodizationappliedinreversedirectionfor10min.Thisgalvaniccyclewillbecarriedthroughuntiltheendofelectrolysis.Thesolutionafterelectrolysiswasconcentratedtohalfthevolumeandkeptovernight,whentheproductSAwasseparatedout.TheobtainedSAwasidentifiedfromitsmeltingpointandIRspectrumwhichwerecomparedwiththoseofauthenticsamples.2ti粒径siphincipersonalrectizact非负性比主体ssiphinfig非负性比co回非价值sicedicketsiceding.........................................................3.3.3.TheanodizationofTiwascarriedoutwithmaleicacidinordertoin-situstudyitselectrocatalyticperformanceontheasanodizedTiO2filmelectrode.Fig.1showstheX-raydiffraction(XRD)patternofTiO2anodizedin0.5mol·L-1H2SO4+1mol·L-1MAfor10minat20Vand50℃.TheXRDinvestigationrevealsthepresenceofbothrutilephaseofTiO2andtitanium.ItisobservedthatpeakscorrespondingtoTiaredominantoverpeaksfortitaniumoxide,whichmeansthattheas-anodizedTiO2hasamixtureoflowcrystalrutilephaseandamorphousstructure.Fig.2showstheAFMimagesofthesurfaceonTiO2anodizedin0.5mol·L-1H2SO4+1mol·L-1MAfor10minat20Vand50℃.ItcanbeseenfromFig.2(a)thatTiO2bundleswithapproximately2-5μminbreadthand20μminlengthcanbeformedinH2SO4-MAelectrolyte.AsshowninFig.2(b),theaspreparedTiO2bundleshavearegulararrangementoffinestick.The3DimageofFig.2(c)showstheaveragediameterofthefinestickwithinthebundlesis80-150nm.ThecyclicvoltammetricbehavioroftheTi/TiO2electrodein0.5mol·L-1H2SO4atascanrateof50mV·s-1isshowninFig.3(A).Tworedoxpeaksareobserved,thefirstcathodicpeakataround-0.57V(vsSCE)andthefirstanodicpeakataround-0.55V,thesecondcathodicpeakataround-0.99Vandthesecondanodicpeakataround-0.92Vareattributedtotworedoxcouples,TiO2/Ti(OH)3andTiO2/Ti2O3,respectively.Theeffectofadding1mol·L-1MAonthecyclicvoltammetricresponseisshowninFig.3(B).ComparedwiththeFig.3(A),thefirstredoxpeakscompletelydisappearandaweakadsorptionprocessataround-0.86Visfoundinsteadofthesecondanodicpeak.Simultaneously,thecathodicpeakisobservedataround-0.91Vinapeakshapedfromamuchhighervalueofcurrent.ThefactthatnotananodicpeakbutanadsorptionprocesswasobservedinaddingMAindicatestheabsenceofTi3+speciesforoxidationonthereversescanandthepresenceofaheterogenouscatalyticchemicalreaction.AstheformationofTiO2byanodization,theTiO2surfaceisboundbyadsorbedMA,andthentheelectrogeneratedTi3+speciesreduceMAtoSA.Themechanismforthereductionprocessisasgivenbelow.TiO2+MA→TiO2·(MA)adTiO2·(MA)ad+H2O+H++e→Ti(OH)3·(MA)adTi(OH)3·(MA)ad→TiO2+SATheresultsofgalvanostaticelectrolysiscarriedoutonMAundervaryingcurrentdensitiesarelistedinTable1.ItisseenthattheyieldofSAisthebestatacurrentdensityof50mA·cm-2(Nos.1-4).Athighercurrentdensity,theyieldandcurrentefficiencydecreaseduetocompetitivehydrogenevolution.Theresultsofexperiment5*showthatthefi

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