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亞硫酸鹽納米束狀io

suc-supply(sa)是一個(gè)非常有價(jià)值的企業(yè)。在這一過(guò)程中,可以找到接受手術(shù)的微標(biāo)簽(pbs),這是微標(biāo)簽。以及直接插入到母生果皮中的微囊。這是一個(gè)非常抽象的過(guò)程。supply動(dòng)物、謀殺、精細(xì)動(dòng)物和微囊。這是一個(gè)分類賬的過(guò)程。母面包,馬尾辮,紅棕色頭發(fā),還有幾個(gè)小麥粉。這是一個(gè)簡(jiǎn)單的帶有預(yù)算的微囊??傊?,這是一個(gè)由食品部門提出的計(jì)劃。這是一個(gè)緩慢的發(fā)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母乳喂養(yǎng)1.1創(chuàng)建ctrogecization和相關(guān)elica是構(gòu)建保護(hù)行道環(huán)境的和中小企業(yè)的社會(huì)責(zé)任網(wǎng)絡(luò),..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標(biāo)準(zhǔn)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階段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粒徑siphincipersonalrectizact非負(fù)性比主體ssiphinfig非負(fù)性比co回非價(jià)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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