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55 个结果
  • 简介:IntroductionTungsten-copperalloypowdersareusedinmanyfieldsonaccountofthehighelectricandthermalconductivitiesofcopperandhighmeltingpointoftungsten.W-Cupowders,aspreparedconventionallybymeansofinfiltration,hasthedisadvantageofinhomogeneityinmicrostructure,andaredifficulttoworkwithaftersintering.

  • 标签: 微观结构 特征 钨-铜合金粉末 活性 高能球磨 机械磨碎法
  • 简介:Bytheadditionalreactionofbinuclearcompounds(Me4N)2M2S4(TDT)2(M=Mo,W;H2TDT=H2CH3C6H3S2)withmononuclearcuprouscomplex,twonewM-Cu-SclustersMo2Cu2S4(TDT)2-(PPh3)2·CH3CH2OH(1)andW2Cu2S4(TDT)2(PPh3)2·0.5CH3CH2OH-0.5H2O(2)havebeenpreparedandcharacterizedbyIR,UV-Vis,31PNMRspectroscopy,cyclicvoltammetryandsinglecrystalX-raystructureanalysis.BothcompoundscrystallizeinspacegroupP21/nwithlatticeparametersa=1.0956(3),b=2.2072(3),c=2.4340(3)nm,β=100.36(2)°,V=5.790(3)nm3andZ=4for1anda=1.0965(9),b=2.2135(3),c=2.4317(4)nm,β=99.63(8)°,V=5.819(8)nm3andZ=4for2.Bothmolecularstructurescontainacubane-likeclustercore[M2Cu2S4](M=Mo,W)andtheirskeletonsarealmostthesameexceptforMatoms.Thesyntheses,structuresandspectrumcharacterizationsofthesetwoclustersarediscussed.Thethird-ordernonlinearoptical(NLO)propertyofthetwoclusterswasstudiedbythetechniqueofforwarddegeneratefour

  • 标签: M-Cu-S(M = MO or W) cluster
  • 简介:Abosonicconstruction(withcentralchargec=2)ofLiealgebrasW1+∞andW1+∞(glN),aswellasthedecompositionsintoirreduciblemodulesaredescribed.AndforW1+∞,whenrestrictedtoitsVirasorosubalgebraVir,abosonicconstructionandthesamedecompositionforVirareobtained.

  • 标签: 玻色子表示法 李代数 Virasoro超代数 不可约模数
  • 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-CuCu-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。

  • 标签: 匹配实验 阻抗匹配 标准材料 铜-铝 检验技术 材料测量
  • 简介:TheviscosityofCumeltisobtainedtobeintherangesfrom2.418to3.039mPa.sundervacuumatmosphere(2Pa),from2.907to3.425mPa.sundernitrogengasatmosphereandfrom3.352to4.015mPa.sunderargongasatmosphere.Theactivationenergyisestimatedtobe0.224,0.162and0.150eVforthevacuumatmosphere(2Pa),nitrogengasatmosphereandargongasatmosphere,respectively.TheresultsreflecttheessentialstructurealchangeintheCumeltbyusingdifferentatmospheres.

  • 标签: CU 热物理性质 粘性 溶化 液体结构
  • 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.

  • 标签: Oxamido-bridge Copper(Ⅱ)-cobalt(Ⅱ) COMPLEXES MAGNETISM
  • 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.

  • 标签: 制备 大孔树脂 固定钯-铜二金属簇合物催化剂
  • 简介:SYNTHESIS AND 183W NMR CHARACTERIZATION OF P4W30Al4(H2O)2O11220- HETEROPOLYANIONSYNTHESISAND183WNMRCHARACTERIZ?..

  • 标签:
  • 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.

  • 标签: 细胞外超氧化物歧化酶 混合酶 结构
  • 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.

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  • 简介:TheadsorptionanddiffusionofNatomsonthethreelow-indexCuplaneswerestudiedusing5-parameterMorsepotential(5-MP)method,andthebesttheory-experimentagreementwasobtained.NatomsofCu(100)surfacesitonthefourfoldhollowsitewiththeverticalheightof0.018nmcloselycoplanarwiththetopmostcopperlayer,andthefourCu-Nbondlengthsare0.182nmandthefifthCu-Ndistanceis0.199nm.ForCu(111)system,theexistenceofaberrantCu(100)reconstructedstructureisapprovedathighercoverage,andatlowcoveragethestructureisalmostanidealCu(111)surfacestructure.WithrespecttoCu(110)system,theNatomsareadsorbedatLBandH3sites,notatSBsite.ThediffusionpassageanddiffusionbarrierofadsorbedNatomswerealsostudied.

  • 标签: 氮原子 铜低指数表面 吸附理论 扩散理论 势能面
  • 简介:Wehaveshownthat,incontrasttotheresultsintheliterature,theBraggpeakintensityofNi80Fe20/Cusuperlatticesisenhancedattheincidentx-rayenergyslightlyhigherthantheabsorptionedgeoftheheavierelement(Cu).TheatomicdensityatNi80Fe20/Cuinterfacewasanalysedbythediffractionanomalousfinestructuretechnologywiththeincidentangleofx-rayfixedatthefirstBraggpeak.OurresultsdemonstratetheepitaxygrowthofNi80Fe20/Cusuperlattices.Uponannealing,theepitaxityofNi80Fe20/Cumultilayersbecomespoorbutthelocalcrystallinityineachlayerisimproved.

  • 标签: X射线分析 微观结构 原子分布 Ni80Fe20/Cu超晶格 晶体生长
  • 简介:Alginate-Cu(Ⅱ)complexbeadsormembraneswerepreparedforremovalofurea.ThemechanismofsorptionofureawasidentifiedbyUV-Visiblespectra,FT-IRspectraandFar-Infraredspectra.Thefactorsaffectingtheureasorptioncapacitywerediscussedindetail.ResultsshowedthattheAlginate-Cu(Ⅱ)complexsorbentcansorbabout60myureapergramofsorbentat37℃andtheconcentrationofureawas130mg/100mlinNa2HPO4andNaH2PO4buffersolution(pH=7.0).

  • 标签: 吸附剂 尿素络合物 吸附作用 藻酸铜络合物
  • 简介:WesuggesttwoschemestogeneratetheWstateofNA-typethree-levelatoms.Intheschemes,identicalNthree-levelatomsaretrappedinacavityorNdistantcavities.ThesuccessorfailureofthegenerationoftheWstatecanbedeterminedbydetectingthepolarizationofphotonleakingoutofthecavity.TheresultdemonstratesthattheWstateisfreefromboththecavitylossandthespontaneousemissionduetothefactthatthetwogroundstates(leftandright)ofthethree-levelatomsarestablestates(ormetastablestates).

  • 标签: 原子物理学 ∧型三层原子结构 光子干涉 W态 单腔 量子纠缠态