简介:Twoseriesofmixedoxides,CoAlMandMgAlM(M=Cr,Mn,Fe,Co,Ni,Cu),werepreparedbycalciningtheircorrespondinghydrotalcite-likecompounds(HTLc).TheratioofMg:Al:M(orCo:Al:M)was3:1:1.ThecatalyticactivityofallsamplesforthereactionofNO+COwasinvestigated.TheresultsshowedthattheactivityofCoAlMwasmuchhigherthanthatofMgAlM.ThestructureandthepropertyofredoxwerecharacterizedbyXRDandH2-TPR.TheresultsindicatedthatonlyMgOphasewasobservedaftercalciningMgAlMhydrotalcites,andthetransitionmetalsbecamemorestable.Thespinel-likephaseappearedinallofCoAlMsamplesafterthecalcination,andthetransitionmetalswerechangedtobemoreactive,andeasilyreduced.TheactivitiesofthreeseriesofmixedoxidesCoAlCuobtainedfromdifferentpreparationmethods,differentratioofCo:Al:Cuandatdifferentcalcinationtemperatures,werestudiedindetailforproposingthemechanismofreaction.TheabilityofadsorptionofNOandCO
简介:ThebindingofCo(bpy)2dppz3+tocalfthymusDNAwasinvestigatedbyusingabsorptionandemissionspectroscopy,DNAmeltingtechniques,cyclicvoltammetry,viscosityandelectro-phoresismeasurements,wherebpyis2,2’-bipyridyl,dppzisdipyrido[3,2-o:2’,3’-c]phenazine.Thebindingcompoundshowsabsorptionhypochromicity,fluorescenceenhancement,andincreasingofDNAmeltingtemperatureandthespecificviscosity.CVmeasurementshowstheshiftsinoxidation-reductionpotentialandchangeinpeakcurrentwithadditionofDNA.ThecompoundisalsoshowntobemoreefficientphotosensitisersforstrandbreaksinplasmidDNA.
简介:用Co2(CO)8与CH3CSNH2反应制得产物Ⅰ,又用Na2Fe(CO)4与Ⅰ反应制得产物Ⅱ(Ⅰ:Co3(μ3-S)(CO)7(CH3CSNH),Ⅱ:Co2Fe(μ3-S)(CO)7(CH3CSNH).通过元素分析。IR、UV、1HNMR、MS表征并用X射线衍射法测得Ⅱ的单晶结构.该簇合物属三斜晶系、PT空间群,晶胞参数:a=0.9203(1),b=1.1296(2),c=1.1425(2)nm;α=116.40°(2),β=101.92°(2),γ=92.58°(1);z=2,V=1.2162nm3,Dc=1.698cm3,μ=21.89cm-1.结构分析表明,Co2FeS构三角锥分子骨架,所有CO均为端基配体,S1为面桥基配体,CH3CSNH为双齿配体,与Co、Fe形成五元环结构.
简介:TwopossiblereactionmechanismsofVS~+(~3∑~-,~1Γ)withCOinthegasphasehavebeenstudiedbyusingB3LYP/TZVPandCCSD(T)/6-311+G(3dr,3pd)methods:theO/Sexchangereaction(VS~++CO→VO~++CS)andtheS-transferreaction(VS~++CO→V~++COS).Thetworeactionsproceedviatwo-stepandone-stepmechanism,respectively.ThebarriersofthetripletandsingletPESsare30.6and50.9kcal/mol,respectively,forO/Sexchangereactionand7.3and50.2kcal/mol,respectively,fortheS-transferreaction.Theresultsindicatethatthetripletgroundstatereactionismorefavorable,andtheS-transferreactionismorefavorablethantheO/Sexchangereaction,whichisingoodagreementwiththeexperimentalobservation.
简介:THE SUPPORTED GOLD CATALYSTS FOR CLOSED CYCLE CO2 LASERTHESUPPORTEDGOLDCATALYSTSFORCLOSEDCYCLECO2LASER¥ZhengPingHAO;LiDunAN;...
简介:Threeheterobinuclearcomplexesweresynthesized,namely[Cu(oxpn)Co(L)2](ClO4)2·xH2O(L=2,2’-bipyridyl(bpy),1,10-phenanthroline(phen),and5-nitro-1,10-phenanthroline(NO2-phen)),whereoxpnrepresentsN,N’-bis(3-aminopropyl)oxam-ido.Basedon1R,elementalanalysis,conductivitymeasurementandelectronicspectra,thesecomplexeswerecharacterizedbyanextendedoxamido-bridgedstructurewithCu(Ⅱ)inaplanarenvironmentandCo(Ⅱ)inaoctahedralenvironment.ThesymmetryofthecationisveryclosetoC2v.Thecomplexeswerealsocharacterizedwithvariabletemperature(4~300K)magneticsusceptibility,andthedatawerefitforthesusceptibilityequationderivedfromspinHamilton,H=-2JS1.S2-DSx12byleastsquarestrategy.Theexchangeintegral,J,wasfoundtobe-22.36cm-1(forbpy);-15.45cm-1(forphen);-19.10cm-1(forNO2-phen),indicatingthatthereisaweakantiferromagneticspin-exchangeinteractionbetweenthemetalions.
简介:[1]G.C.Chinchen,P.J.Denny,J.R.Jennings,M.S.Spencer,K.C.Waugh,Appl.Catal.,1988,36,1.[2]R.A.Koppel,A.Baiker,Appl.Catal.,1992,84,77.[3]M.Satio,T.Fujitani,M.Takeuchi,T.Watanabe,Appl.Catal.,1996,138,311.[4]J.A.Brown,N.Homs,A.T.Bell,J.Catal.,1990,124,73.[5]J.S.Lee,K.Moon,S.H.Lee,S.Y.Lee,Y.G.Kim,Catal.Lett.,1995,34,93.[6]C.Frohlich,R.A.Koppel,A.Baiker,M.Kilo,A.Wokaun,Appl.Catal.,1993,106,275.[7]J.F.Deng,Q.Sun,Y.L.Zhang,D.Wu,S.Y.Chen,Appl.Catal.,1996,139,75.[8]K.K.Bando,K.Sayama,H.Kusama,K.Okabe,H.Arakawa,Appl.Catal.,1997,165,391.[9]G.C.Chinchen,K.C.Waugh,D.A.Whan.Appl.Catal.,1986,25,101.[10]B.Denise,R.P.A.Sneeden,B.Beguin,O.Cherifi.Appl.Catal.,1987,30,353.[11]G.C.Chinchen,K.C.Waugh.J.Catal.,1986,97,280.[12]T.H.Fleisch,R.L.Mieville.J.Catal.,1984,90,165.[13]K.Klier,V.Chatikavanij,R.G.Herman,G.W.Simmons.J.Catal.,1982,74,343.[14]R.Burch,R.J.Chappel.Appl.Catal.,1992,45,65.[15]H.Berndt,V.Briehn,S.Evert.Appl.Catal.,B,1992,86,65.[16]W.P.Dow,Y.P.Wang,T.J.Huang.J.Catal,1996,160,155.
简介:在水的答案的Co3+水和上的详细理论调查借助于模拟基于原子契约electronegativity均等方法熔化了进分子的力学(ABEEM/MM)的分子的动力学(MD)被执行了。有效Co3+离子水潜力被为离子的簇适合到abinitio结构和有约束力的精力构造了。然后离子水相互作用潜力与ABEEM-7P水模型一起在联合被用于单个Co3+(aq)答案的分子的动力学模拟,设法复制答案的许多试验性的结构、动态的性质。这里,不是仅仅共有的财产(光线的分发功能,尖分发功能和solvation精力)获得了因为在ABEEM-7P水答案的Co3+在对从试验性的方法和另外的分子的动力学模拟而且费用分布的很有趣的性质的那些的好同意,水分子的几何学,氢债券,散开系数,震动的系列被ABEEM/MM调查模型。
简介:NanocrystallineanataseTiO2filmswithindiumtinoxide(ITO)coatedglassasthefilmsubstratewerefabricatedthroughspin-coatingtechnique.TheTiO2pasteswerepreparedwithsodiumdodecylbenzenesulfonate(DBS)modifiedTiO2nanocrystals,synthesizedbysol-hydrothermalprocessesinadvance,togetherwithdifferentamountsofpolyethyleneglycol(PEG)macromolecules.Theas-preparedfilmsweremainlycharacterizedbyultraviolet-visible(UV-Vis)spectroscopy,fieldemissionscanningelectronmicroscopy(FE-SEM)andwatercontactangle(WCA)measurement.EffectsoftheadditionofDBSandPEGonthewettingperformanceoftheresultingfilmsandrelevantmechanismswereprincipallyinvestigated.Theresultsshowthattheas-preparedfilmdisplayssuper-hydrophilicpropertyafterco-additionofDBSandPEGalthoughitisnotexposedtoultravioletlightpriortotheWCAmeasurement.Thisappealingresultismainlyattributedtotheproducedmicroandnanometer-scalehierarchicalsurfacestructurewithuniformlydispersedmicropapillae.EachpapillawasmadeupofagreatnumberofTiO2nanoparticles.ThepossibleformationmechanismsrelatedtotheDBSamphiphilicpropertyofthecharacteristicsurfacewerealsosuggested.Moreover,theresultingfilmalsoexhibitsconsiderabledurabilityinthesuperhydrophilicity,whichisveryusefulforpracticalapplicationinself-cleaning,anti-fogging,andbacteria-resistantfields.
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简介:ElectrolyticfixationofCO2wasinvestigatedbyelectrocarboxylationoforganichalides(RX),andfourestersⅠ,ⅡⅢ,Ⅳ)wereobtainedinmoderateyields.ElectrochemicalreductionesterificationsofRXinthepresenceofCO2werecarriedoutonnanocry'stallineTiO2-Ptelectrode.TheelectrochemicalbehaviorofRXinthepresenceofCO2wasinvestigatedbythetechniqueofcyclicvoltammetry,andtheprobablereactionmechanismw,asproposed.
简介:Muchattentionhasbeenpaidtothedevelopmentofnewpolymerelectrolytewithspecialmorphology,soastoimprovetheirelectrochemicalpropertiestomeettheneedsoflithium(ion)battery.Inthiswork,PEMlatexwassynthesizedbyemulsion-fi-eepolymerization.ThemicrophotoofPEMlate...
简介:AnAu/ceria(0.44%,massfraction)catalystcontaininggoldionswaspreparedbyamodifieddepositionprecipitationmethod,andtheevolutionofgoldionsinthecatalystanditsinfluenceonthecatalysisofCOoxidationwereinvestigated.Itwasfoundthattheas-preparedcatalystcontaininggoldionswithhighvalencecouldfullyoxidizeCOat–10°CinitiallybutwasdeactivatedgraduallyatlowtemperaturesduringthereactionwithCOortreatmentbyunpurifiedair.ThedeactivationofthecatalystduringCOoxidationortreatmentofitbyunpurifiedairwasindependentandprogressiveatlowtemperatureswhiletheactivityofthecatalystatrelativelyhightemperatureswasmaintainedwell.DuringthereactionwithCOortreatmentbyunpurifiedair,theXPSresultsindicatethatgoldspeciesevolvedfromhighvalencetolowvalenceandthediffusereflectanceUV-Visspectrashowthathighvalencegoldwasreducedtochargedgoldclusters,goldclustersgrewtosmallgoldcrystalsandsmallgoldcrystalsgrewtolargegoldparticles.Accordingly,thehighvalencegoldcorrespondedtotheactivityatlowtemperaturesandthemetallicgoldwasactiveandrelativelystableathightemperatures.Theturnoverfrequencies(TOF)ofthecatalyststreatedbydifferentmethodsat273Kdecreasedwiththeevolutionofgoldspeciesfromhighvalencetolowvalence,nomaximumofTOFwasobservedalthoughgoldparticlesinthecatalystattainedtoabout2―3nmduringthetreatment.AnAu/ceriacatalystwithagoldloadof0.87%(massfraction)maintainedagoodactivityforCOoxidationwithin18hatroomtemperature.Thecatalystswerecharacterizedviatransmittedelectronicmicroscopy(TEM),inductivelycoupledplasmaopticalemissionspectrometry(ICP-OES),X-raydiffraction(XRD)andBETspecificsurfaceareaandUV-VisDRSaswell.
简介:Theepoxideisakindofversatileintermediateformanufactureofawidevarietyoffinechemicals.Thegoalofmodemefficientcatalyticmethodsistoproducedesiredcompoundswithhighyield,selectivity,lowcost,safety,operationalsimplicityandmoreimportantlyenvironmentallybenignmanner.However,therearevariousoxidants,whichareoftenhazardousorexpensive,beingusedforbothlaboratoryandindustrialepoxidation.Hydrogenperoxide(30wt%)solutionisthoughtasoneoftheidealoxidantsbecausewaterisasoletheoreticalsideproduct.Meanwhiletheepoxidationofstyreneisatypicaloneamongolefins.Here,theperformanceofstyreneepoxidationwasstudiedwithhydrogenperoxidesolutioncatalyzedbyCo(Ⅱ)phenanthrolinecomplexencapsulatedinsupercagesofMCM-41.