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463 个结果
  • 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.

  • 标签: 铜离子吸附 半导体表面 水合 Si(111)表面 硅层 B3LYP方法
  • 简介:ThemorphologyandcrystallographyofphasesintheCu-0.12%Zralloywereinvestigatedbyscanningelectronmicroscope(SEM),transmissionelectronmicroscope(TEM),andhigh-resolutiontransmissionelectronmicroscope(HRTEM).Theresultsshowthattheas-castmicrostructureofCu–ZralloyismainlyCumatrixandeutecticstructurewhichconsistofCuandCu5Zrphaseswithafinelamellarstructure.Thedisk-shapedandplatelikedCu5Zrphaseswithfccstructurearefoundinthematrix,inwhichhabitplaneisparallelto{111}aplaneofthematrix.BetweenthecoppermatrixandCu5Zrphase,thereexistsanorientationrelationshipof[112]a||[011]Cu5Zr;(111)a||(111)Cu5Zr.ThespacestructuremodelofCu5Zrphasecanbeestablished.

  • 标签: Cu–Zr ALLOY MICROSTRUCTURE Crystal structure MORPH
  • 简介:InordertosuppressthesurfacecrackinginducedbyCuduringreheatingandhotrollingprocess,Cuenrichmentanditsmigrationatthesteel-scaleinterfacewasinvestigatedduringheatingofsteelcastattemperaturesbetween1000℃and1200℃inN2-O2andN7-H2Oatmospheres.ForoxidationofCucontainingsteel,CuenrichedphasewasformedbythepreferentialoxidationofFeandtheenrichmentandmigrationbehaviorofCudependsontheoxidationtemperature,steelchemistryandatmospherecondition.NiinsteelinducedtheformationofsolidCuandNienrichedphaseatsteel/scaleinterfaceandinscalelayerandtheformationofunevensteel/scaleinterface,whichsuppressestheCuenrichmentbecauseofextrusionofCuenrichedregionbeforetheformationofliquidphase.Ontheotherhand,SnadditionpromotestheliquidCuformationatsteel/scaleinterfaceandpenetrationintograinboundaryofCuenrichedphasebydecreasingsolidustemperatureandsolubilitylimit.Inaddition,foroxidationat1200℃,thebehaviorofCuatandaroundthesteel-scaleinterfacewasfounddependenttoalargeextentonmorphologyoftheoxidescaleformedduringoxidation.Attheearlystageofoxidation,Cu-richphaseformedandaccumulatedatthesteelscaleinterfaceunderbothO2-N2andH2O-N2atmospheres.Astheoxidationproceeded,however,Cuenrichmentatanditsmigrationfromthesteel-scaleinterfacewerevastlydifferentfordifferentoxidizingatmospheres.InthecaseofO2-N2oxidation,anoxidelayerformedinitiallyatthesteelsurface,butsoonafteragapwasdevelopedatthesteel-scaleinterfaceandgrewinitssize,whichpracticallyseparatedthescalefromthesteelsubstrate.Thescalelayerformedunderthisconditionwasporous.TheCu-richphaseinitiallyformedattheinterfacewasfoundmigratingtothescalelayer,leavingnoCu-richphaseattheinterface.InthecaseofH2O-N2oxidation,however,thescalelayerformedwasdenseandtightlyattachedtothesteelsurface,andtheCurich-phasecontinuedto

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

  • 标签: CU2O OXIDATION plasma molecular BEAM EPITAXY
  • 简介:介绍一种金属/合金的生产方法,用于恒电流和恒电位条件下由混合硫化物(Cu2S,NiS)生产Cu-Ni合金,称为直接电化学还原(DER)。研究槽电压和槽电流等工艺参数对还原得到的化合物组成的影响,以生产工业所需的CuNi10,CuNi20和CuNi30等合金。在1200°C下采用循环伏安法(CV)考察Cu2S和NiS在CaCl2熔体中的电化学行为。根据CV研究结果,Cu2S的阴极还原是一步完成的,即Cu2S?Cu;NiS的阴极还原则分两步进行,即NiS?Ni3S2?Ni。恒电流研究表明,在10A电流下电解15min,可制备出最高硫含量为320×10-6的高纯CuNi10合金。扫描电子显微镜以及能量色散X射线能谱和光学发射光谱(OES)测试结果表明,在2.5V电压下直接电化学还原15min,可制备出杂质含量低(即硫含量小于60×10-6)的所选成分的Cu-Ni合金。

  • 标签: 熔盐电解 电还原 铜提取 硫化铜 硫化镍 CU-NI合金
  • 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.

  • 标签: C02 VALORIZATION ELECTRO-REDUCTION CU catalyst PEM
  • 简介:摘要:在当今信息化时代,随着科技的不断发展和人们生活水平的提高,人们对于学习方式的需求也在不断地变化。传统的课堂教学已经不能满足现代人的需求,因此越来越多的人开始关注在线教育的发展趋势。而智慧教育作为一种新型的在线教育形式,以其灵活性和个性化的特点受到了广泛的关注和认可。在这种背景下,CU公司作为一家专注于智慧教育产品的企业,其市场前景十分广阔。本文将从市场分析入手,重点分析CU公司智慧教育产品营销策略,旨在促进公司持续健康发展。

  • 标签: CU公司 智慧教育产品 市场 营销策略
  • 简介:TheSOD-likeactivityoffiveCu(Ⅱ)complexes[Cu(HSal)_2·EtOH,Cu(Gly)_2,Cu(Lys)_2,Cu(His)_2,Cu(Try)_2]havebeenstudiedbyusingcytochromeCmethod,aswellaschemilumine-scenceandESRtechnique.Thefoursurfactants(CTAB,SDS,TritonX-100andTween20)werepurifiedandtheircriticalmiceileconcentration(CMC)inphosphatebuffer(pH=7.4)wasmea-sured.TheeffectsoffoursurfactantsonO_2~-havebeeninvestigated.Theco-operativeeffectsof

  • 标签: 铜络合物 SOD类活性 微团
  • 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:Comparativestudyontheactivityandkinecticpropertiesofacidphosphatase(ACPase)ofthreesoilsamendedwithHgandCuatconstanttemperatureandhumiditywascarriedout.TheresultsindicatedthattheinhibitiononACPaseofthethreesamplesoilsbyHgandCuvariedwiththecontentofsoilorganicmatterandpH,where,Soil1wasthemostseriouslycontami-natedduetoitslowestcontentoforganicmatterandthelowestpHamongthreesamples,Soil2tookthesecondplace,andSoil3wastheleastcontaminated.ExceptSoil3,theactivityofsoilACPasetendedtoincreasealongwiththecontacttimeunderthesametypeandthesameconcentrationofheavymetal.InparticulartheVmaxvaluesofACPaseinallthreesamplesdecreasedwithincreasingHgandCuconcentration,whereastheKmvalueswereaffectedweakly.AccordingtothechangeofVmaxandKmvalues,CuandHghadthesameinhibitioneffectonsoilACPase.Bothofthemmaybeatypeofcompoundofnon-competitiveandanti-competitiveinhibition.StatisticanalysesindicatedthatactivitiesofsoilACPaseandVmaxvaluescouldserveasbioindicatortopartiallydenotetheheavymetalHgandCucontaminationdegree.

  • 标签: 生物活度 土壤酸化 磷酸酶 生物化学
  • 简介:本文首次利用异常衍射精细结构谱(DAFS)分析技术对多层膜中的NiFe和Cu的精细结构进行了分析。从DAFS谱中,我们提取出Ni和Cu的精细结构谱,从而可以单独研究多层膜中NiFe和Cu的精细结构。与荧光EXAFS谱的比较表明,两种方法得到的谱线完全一致。该技术为研究超薄多层膜的精细结构提供一种强有力的工具。

  • 标签: DAFS NiFe/Cu多层膜 结构 超薄金属多层膜 异常衍射精细结构谱