简介：ＴＨＥ ＳＵＰＰＯＲＴＥＤ ＧＯＬＤ ＣＡＴＡＬＹＳＴＳ ＦＯＲ ＣＬＯＳＥＤ ＣＹＣＬＥ ＣＯ２ ＬＡＳＥＲＴＨＥＳＵＰＰＯＲＴＥＤＧＯＬＤＣＡＴＡＬＹＳＴＳＦＯＲＣＬＯＳＥＤＣＹＣＬＥＣＯ２ＬＡＳＥＲ￥ＺｈｅｎｇＰｉｎｇＨＡＯ；ＬｉＤｕｎＡＮ；...
简介：ElectrolyticfixationofCO2wasinvestigatedbyelectrocarboxylationoforganichalides(RX),andfourestersⅠ,ⅡⅢ,Ⅳ)wereobtainedinmoderateyields.ElectrochemicalreductionesterificationsofRXinthepresenceofCO2werecarriedoutonnanocry'stallineTiO2-Ptelectrode.TheelectrochemicalbehaviorofRXinthepresenceofCO2wasinvestigatedbythetechniqueofcyclicvoltammetry,andtheprobablereactionmechanismw,asproposed.
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：
简介：TostudytheintramolecularDiels-Aldercycloadditonof2H-chromen-2-oneasadiene,aseriesofchiralN-allyl-N-benzylamidesthatcontaina2H-chromen-2-onemoietyweredesignedforthesynthesisofbenzo[f]isoindol-l-onesviaanintramolecularDiels-Alderandasubsequentretro-Diels-AldercycloadditionwiththeexpulsionofCO2.Boththeyield（80%-89%）andabsolutestereocontrolofthetandemreactionwerehighwhenanelectron-withdrawinggroupwasattachedtothedienophile.Thedoublebondinthestyrenesubstructureremainedintheproductscouldbefurtherderivatizedbydihydroxylation.
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：Themonomericcobalt-phosphite-thiolatocomplex[Co(mpt)2{P(OCH3)3}2]BF4(Hmpt=2-mercaptothiazoline)hasbeenpreparedandcharacterizedbyX-raycrystallography.ThecomplexcrystallizesinthemonoclinicspacegroupC2/cwitha=0.8078(5),b=2.6020(18),c=1.2191(7)nm,β=99.38(1)°,V=2.528(3)nm3,andZ=4.Thestructurecomprisesdiscretecations[Co(mpt)2{P(OCH3)3}2.]+andanionsBF4-,inwhichthecobalt(Ⅲ)atomiscoordinatedtotwochelatempt-andtwoas-orientedmonodentateP(OCH3)3ligandsinahighlydistortedoctahedralgeometry.ThemostdistortedanglesareS(2)-Co(1)-S(2a)of162.23(10)°andN(1)-Co(1)-S(2)of71.47(13)°,thelatteriscausedbythegeometricconstraintofthebidentateligandmpt-.CyclicvoltammetryhasbeenusedtostudytheelectrochemicalbehaviorofthetitlecomplexontheRelectrodeinMeCNsolutionwith0.1mol·L-1ofBun4NBF4aselectrolyte.TheresultsindicatethatthetitlecomplexisunstableinMeCN.
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.
简介：HighactiveandstablegoldcatalystssupportedoncrystallineFe2O3andCeO2/Fe2O3werepreparedviathedeposition-precipitationmethod.ThecatalystwithaAuloadof1.0%calcinedat180°CshowedaCOconversionof100%at-8.9°C,whileAu/CeO2/Fe2O3convertedCOcompletelyat-16.1°C.Evenhavingbeencalcinedat500°C,Au/Fe2O3stillexhibitedsignificantcatalyticactivity,achievingfullconversionofCOat61.6°C.ThecatalystwithalowAuloadof0.5%couldconvertCOcompletelyatroomtemperatureandkepttheactivityunchangedforatleast150h.N2adsorption-desorptionmeasurementsshowthatthecrystallinesupportspossessedahighspecificsurfaceareaofabout200m2/g.CharacterizationsofX-raydiffractionandtransmissionelectronmicroscopyindicatethatgoldspecieswerehighlydispersedasnanoorsub-nanoparticlesonthesupports.Evenafterthecatalystwascalcinedat500°C,theAuparticlesremainedinanano-sizeofabout6―10nm.X-rayphotoelectronspectrarevealthatthesupportedAuexistedinmetallicstateAu0.ThemodificationofAu/Fe2O3byCeO2provedtobebeneficialtotheinhibitionofcrystallizationofFe2O3andthestabilizationofgoldparticlesindispersedstate,consequentlypromotingcatalyticactivity.
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：N酰--hydroxy-4-phenyl-oxazolidinethiones能被处理很快在高收益变换成他们的乙醇thiol酉旨与在0è的EtSH
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![Synthesis and crystal structure of [<b style='color:red'>Co</b>（mpt）<b style='color:red'>2</b>{P（OCH3）3}<b style='color:red'>2</b>]BF4 （Hmpt = <b style='color:red'>2</b>-mercaptothiazoline）](/image/thesis11 "Synthesis and crystal structure of [<b style='color:red'>Co</b>（mpt）<b style='color:red'>2</b>{P（OCH3）3}<b style='color:red'>2</b>]BF4 （Hmpt = <b style='color:red'>2</b>-mercaptothiazoline）")
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![Crystal Structure, Thermal Decomposition Behavior and the Standard Molar Enthalpy of Formation of a Novel 3D Hydrogen- Bonded Supramolecular [<b style='color:red'>Co</b>（HnicO）<b style='color:red'>2</b>·（H<b style='color:red'>2</b>O）<b style='color:red'>2</b>]](/image/thesis17 "Crystal Structure, Thermal Decomposition Behavior and the Standard Molar Enthalpy of Formation of a Novel 3D Hydrogen- Bonded Supramolecular [<b style='color:red'>Co</b>（HnicO）<b style='color:red'>2</b>·（H<b style='color:red'>2</b>O）<b style='color:red'>2</b>]")
![配合物{[<b style='color:red'>Co</b>（5-氨基-8-羟基喹啉）_<b style='color:red'>2</b>]·H_<b style='color:red'>2</b>O}_n的合成及结构研究](/image/thesis18 "配合物{[<b style='color:red'>Co</b>（5-氨基-8-羟基喹啉）_<b style='color:red'>2</b>]·H_<b style='color:red'>2</b>O}_n的合成及结构研究")
![LDH-[PW7Mo3Cu<b style='color:red'>2</b>O38（H<b style='color:red'>2</b>O）<b style='color:red'>2</b>]（M=Fe<b style='color:red'>2</b>＋，<b style='color:red'>Co</b><b style='color:red'>2</b>＋，Cu<b style='color:red'>2</b>＋，Ni<b style='color:red'>2</b>＋和Mn<b style='color:red'>2</b>＋）层状化合物的合成、表征及催化活性](/image/thesis19 "LDH-[PW7Mo3Cu<b style='color:red'>2</b>O38（H<b style='color:red'>2</b>O）<b style='color:red'>2</b>]（M=Fe<b style='color:red'>2</b>＋，<b style='color:red'>Co</b><b style='color:red'>2</b>＋，Cu<b style='color:red'>2</b>＋，Ni<b style='color:red'>2</b>＋和Mn<b style='color:red'>2</b>＋）层状化合物的合成、表征及催化活性")