简介：TostudytheadsorptionbehaviorofCu+inaqueoussolutiononsemiconductorsurface,theinteractionsofCu+andhydratedCu+cationswiththecleanSi(111)surfacewereinvestigatedviahybriddensityfunctionaltheory(B3LYP)andMller-Plessetsecond-orderperturbation(MP2)method.ThecleanSi(111)surfacewasdescribedwithclustermodels(Si14H17,Si16H20andSi22H21)andafour-siliconlayerslabunderperiodicboundaryconditions.CalculationresultsindicatethatthebondingnatureofadsorptionofCu+onSisurfacecanbeviewedaspartialcova-lentaswellasionicbonding.ThebindingenergiesbetweenhydratedCu+cationsandSi(111)surfacearelarge,suggestingastronginteractionbetweenthem.ThecoordinationnumberofCu+(H2O)nonSi(111)surfacewasfoundtobe4.Asthenumberofwatermoleculesislargerthan5,watermoleculesformahydrogenbondnetwork.Inaqueoussolution,Cu+cationswillsafelyattachtothecleanSi(111)surface.

简介：在传统的利用化爆和二级轻气炮作为驱动源的状态方程阻抗匹配实验中，为了考核不同标准材料的可信度，采用了标准材料交叉检验技术。即依次利用这些标准材料作为测量某个待测材料测量雨贡纽线的标准材料，通过比较待测材料雨贡纽线数据的一致性实现对这些标准材料的检验。2004年在神光-Ⅱ装置上完成的二倍频激光Al-Cu和Cu-A1阻抗匹配实验，是一种交叉实验。这两类实验不仅铝、铜二者互为标准材料和待测材料，而且实验包含了正反阻抗匹配两种类型：铝-铜正阻抗匹配实验中冲击波由低阻抗铝进入高阻抗待测材料铜，铜-铝反阻抗匹配实验中冲击波由高阻抗铜进入低阻抗待测材料铝中。

简介：TheroleoftemperatureontheoxidationdynamicsofCu2OonZnO(0001)wasinvestigatedduringtheoxidationofCu(111)/ZnO(0001)byusingoxygenplasmaastheoxidant.AtransitionfromsinglecrystallineCu2O(111)orientationtomicro-zonephaseseparationwithmultipleorientationswasrevealedwhentheoxidationtemperatureincreasedabove300°C.TheexperimentalresultsclearlyshowtheeffectoftheoxidationtemperaturewiththeassistanceofoxygenplasmaonchangingthemorphologyofCu(111)filmandenhancingthelateralnucleationandmigrationabilitiesofcuprousoxides.Averticaltop-downoxidationmodeandalateralmigrationmodelwereproposedtoexplainthedifferentnucleationandgrowthdynamicsofthetemperature-dependentoxidationprocessintheoxidationofCu(111)/ZnO(0001).

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简介：Anovelgas-phaseelectrocatalyticcellcontainingalow-temperatureprotonexchangemembrane(PEM)wasdevelopedtoelectrochemicallyconvertCO2intoorganiccompounds.TwodifferentCu-basedcathodecatalysts(CuandCu-C)werepreparedbyphysicalvapordepositionmethod(sputtering)andsubsequentlyemployedforthegas-phaseelectroreductionofCO2atdifferenttemperatures(70-90℃).ThepreparedelectrodesCuandCu-CwerecharacterizedbyX-raydiffraction(XRD),X-rayphotoemissionspectroscopy(XPS)andscanningelectronmicroscopy(SEM).Asrevealed,CuispartiallyoxidizedonthesurfaceofthesamplesandtheCuandCu-Ccathodiccatalystswerecomprisedofaporous,continuous,andhomogeneousfilmwithnanocrystallineCuwithagrainsizeof16and8nm,respectively.Theinfluenceoftheappliedcurrentandtemperatureontheelectro-catalyticactivityandselectivityofthesematerialswasinvestigated.Amongthetwoinvestigatedelectrodes,thepureCucatalystfilmshowedthehighestCO2specificelectrocatalyticreductionratesandhigherselectivitytomethanolformationcomparedtotheCu-Celectrode,whichwasattributedtothehigherparticlesizeoftheformerandlowerCuO/Curatio.Theobtainedresultsshowpotentialinterestforthepossibleuseofelectrical「enewableenergyforthetransformationofCO2intovaluableproductsusinglowmetalloadingCubasedelectrodes(0.5mgCucm2)preparedbysputtering.

简介：TheviscosityofCumeltisobtainedtobeintherangesfrom2.418to3.039mPa.sundervacuumatmosphere(2Pa),from2.907to3.425mPa.sundernitrogengasatmosphereandfrom3.352to4.015mPa.sunderargongasatmosphere.Theactivationenergyisestimatedtobe0.224,0.162and0.150eVforthevacuumatmosphere(2Pa),nitrogengasatmosphereandargongasatmosphere,respectively.TheresultsreflecttheessentialstructurealchangeintheCumeltbyusingdifferentatmospheres.

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简介：Comparativestudyontheactivityandkinecticpropertiesofacidphosphatase(ACPase)ofthreesoilsamendedwithHgandCuatconstanttemperatureandhumiditywascarriedout.TheresultsindicatedthattheinhibitiononACPaseofthethreesamplesoilsbyHgandCuvariedwiththecontentofsoilorganicmatterandpH,where,Soil1wasthemostseriouslycontami-natedduetoitslowestcontentoforganicmatterandthelowestpHamongthreesamples,Soil2tookthesecondplace,andSoil3wastheleastcontaminated.ExceptSoil3,theactivityofsoilACPasetendedtoincreasealongwiththecontacttimeunderthesametypeandthesameconcentrationofheavymetal.InparticulartheVmaxvaluesofACPaseinallthreesamplesdecreasedwithincreasingHgandCuconcentration,whereastheKmvalueswereaffectedweakly.AccordingtothechangeofVmaxandKmvalues,CuandHghadthesameinhibitioneffectonsoilACPase.Bothofthemmaybeatypeofcompoundofnon-competitiveandanti-competitiveinhibition.StatisticanalysesindicatedthatactivitiesofsoilACPaseandVmaxvaluescouldserveasbioindicatortopartiallydenotetheheavymetalHgandCucontaminationdegree.

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简介：IntroductionTungsten-copperalloypowdersareusedinmanyfieldsonaccountofthehighelectricandthermalconductivitiesofcopperandhighmeltingpointoftungsten.W-Cupowders,aspreparedconventionallybymeansofinfiltration,hasthedisadvantageofinhomogeneityinmicrostructure,andaredifficulttoworkwithaftersintering.

简介：Wereportthemicrostructureevolutionofcopper(Cu)nm-sizedatomicislandsonsiliconeoilsurfacesintheambientatmosphere.Theoriginofthesenearlyfreesustainingatomicislandsisexplainedbyathree-stagegrowthmodel.Thefirststageisthenucleationandgrowthofatomicgranules.Subsequently,thecompactatomicislandsgrowbytheaggregationoftheatomicgranules.Finally,theyadheretoeachotherandformbranchedatomicislands.Duringthecharacteristicevolution,theatomicgranulesreconstructandtheaverageheightoftheatomicislandsincreasesfrom7.0±1.0nmto13.0±1.0nm.ThedetailedevolutionmechanismoftheCuatomicislandsispresented.

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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：TherecentdevelopmentofCu-basedelectrocatalystsforelectrochemicalreductionofcarbondioxide（CO2）hasattractedmuchattentionduetotheiruniqueactivityandselectivitycomparedtoothermetalcatalysts.Particularly,CuistheuniqueelectrocatalystforCO2electrochemicalreductionwithhighselectivitytogenerateavarietyofhydrocarbons.Inthisreview,wemainlysummarizetherecentadvancesontherationaldesignofCunanostructures,thecompositionregulationofCu-basedalloys,andtheexploitationofadvancedsupportsforimprovingthecatalyticactivityandselectivitytowardelectrochemicalreductionofCO2.ThespecialfocusistodemonstratehowtoenhancetheactivityandselectivityofCubasedelectrocatalystforCO2reduction.TheperspectivesandchallengesforthedevelopmentofCu-basedelectrocatalystsarealsoaddressed.WehopethisreviewcanprovidetimelyandvaluableinsightsintothedesignofadvancedelectrocatalyticmaterialsforCO2electrochemicalreduction.

简介：TheSolvatedMetalAtomImpregnation(SMAI)techniquewasemployedtopreparemacroporousresinimmobilizedPd-Cubimetallicclustercatalysts.TheX-raydiffraction(XRD)andtransmissionelectronmicrograph(TEM)showedthatPd-CualloywasformedandtheparticlesizesofPd-Cuclusterswereverysmall,withaveragediameters<3nm.X-rayphotoelectronspectroscopyindicatedthatbothPdandCuwereinzero-valentstate.ThecatalyticactivitiesofthemacroporousresinimmobilizedPd-Cucatalystsinhydrogenationof4-methyl-3-penten-2-oneweremuchgreaterthanthatofthecarbonsupportedPd-Cucatalysts.

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简介：Humanextracellularsuperoxidedismutase(hEC-SOD)isasecretedtetramericproteininvolvedintheprotectionofahumanbodyfromoxygenfreeradicals.Itsthree-dimensionalstructurehasnotbeenconfirmed,hEC-SODcouldn′tbeexpressedinE.coll.Weconstructedahybridenzyme,whichcomprisestheNterminalandC-terminaldomainsfromhEC-SOD,fusedittohumanCu,Zn-SOD.ThehybridenzymeisexpressedsuccessfullyinE.coli.Further,weanalyzedtheexpressionofhEC-SODinE.colibymRNAdifferentialdisplaying.

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：Theadsorptionandelectronicpropertiesofisolatedcobaltphthalocyanine(CoPc)moleculeonanultrathinlayerofNaClhavebeeninvestigated.High-resolutionSTMimagesgiveadetailedpictureofthelowestunoccupiedmolecularorbital(LUMO)ofanisolatedCoPc.ItisshownthattheNaClultrathinlayerefficientlydecouplestheinteractionofthemoleculesfromtheunderneathmetalsubstrate,whichmakesitanidealsubstrateforstudyingthepropertiesofsinglemolecules.Moreover,strongdependenceoftheappearanceofthemoleculesonthesamplebiasintheregionofrelativelyhighbias(>3.1V)isascribedtotheimagepotentialstates(IPSs)ofNaCl/Cu(100),whichmayprovideuswithapossiblemethodtofabricatequantumstoragedevices.