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
简介:TheviscosityofCumeltisobtainedtobeintherangesfrom2.418to3.039mPa.sundervacuumatmosphere(2Pa),from2.907to3.425mPa.sundernitrogengasatmosphereandfrom3.352to4.015mPa.sunderargongasatmosphere.Theactivationenergyisestimatedtobe0.224,0.162and0.150eVforthevacuumatmosphere(2Pa),nitrogengasatmosphereandargongasatmosphere,respectively.TheresultsreflecttheessentialstructurealchangeintheCumeltbyusingdifferentatmospheres.
简介:Comparativestudyontheactivityandkinecticpropertiesofacidphosphatase(ACPase)ofthreesoilsamendedwithHgandCuatconstanttemperatureandhumiditywascarriedout.TheresultsindicatedthattheinhibitiononACPaseofthethreesamplesoilsbyHgandCuvariedwiththecontentofsoilorganicmatterandpH,where,Soil1wasthemostseriouslycontami-natedduetoitslowestcontentoforganicmatterandthelowestpHamongthreesamples,Soil2tookthesecondplace,andSoil3wastheleastcontaminated.ExceptSoil3,theactivityofsoilACPasetendedtoincreasealongwiththecontacttimeunderthesametypeandthesameconcentrationofheavymetal.InparticulartheVmaxvaluesofACPaseinallthreesamplesdecreasedwithincreasingHgandCuconcentration,whereastheKmvalueswereaffectedweakly.AccordingtothechangeofVmaxandKmvalues,CuandHghadthesameinhibitioneffectonsoilACPase.Bothofthemmaybeatypeofcompoundofnon-competitiveandanti-competitiveinhibition.StatisticanalysesindicatedthatactivitiesofsoilACPaseandVmaxvaluescouldserveasbioindicatortopartiallydenotetheheavymetalHgandCucontaminationdegree.
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。
简介:通过水培法研究了不同Cu2+浓度(0.5,1.0,2.5,5.0,10.0mg/L)对水生植物凤眼莲[Eichhorniacrassipes]蛋白质含量、根系活力及Cu2+-ATP酶活性的影响.结果表明,Cu2+胁迫对凤眼莲蛋白质含量、根系活力及Cu2+-ATP酶活性的影响与Cu2+胁迫浓度及胁迫时间均有关,在Cu2+胁迫时间为1,3,10d时,各Cu2+胁迫浓度下均有利于凤眼莲叶片蛋白质含量的积累.一定浓度和时间的Cu2+胁迫使凤眼莲体内蛋白质含量应激积累增多.在Cu2+胁迫时间为1d时,随着Cu2+浓度的增加,凤眼莲根系活力逐渐增大;当胁迫时间达10d时,根系活力在Cu2+浓度为1.0mg/LCu2+时达最大,以后逐渐降低.试验表明,随着Cu2+浓度的增加,叶片Cu2+-ATP酶活性在0.5mg/L时达最大,之后逐渐降低;随Cu2+浓度的增加根系Cu2+-ATP酶活性的变化趋势与叶片Cu2+-ATP酶活性的变化趋势相似.
简介:SiCp/AI金属矩阵的表面上的紧缩的氧化物合成(SiCp/AIMMC)极大地取决于关节的性质。镶嵌的劈啪作响的目标被使用由血浆侵蚀在SiCp/AIMMC的结合的表面上完全蚀刻氧化物。在厚度的5妈妈的Cu/Ni/Cu电影被磁控管劈啪作响方法在一样的真空房间在干净结合表面上准备,它在结合的短暂液相(TLP)作为夹层被扮演过程。与单个Cu陪衬和Ni陪衬夹层的一样的厚度相比,200MPa的shear力量在TLP结合期间用Cu/Ni/Cu电影夹层被获得,它是89.7%碱金属的。另外,结合的区域的
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简介:Thedevelopmentofconvenientmethodtoobtaingraphene-basednanocompositesisakeyissuefortheirapplication.Herein,wedescribedafacilerouteforsynthesizinggraphene-Cuandgraphene-Cu2Onanocompositesusinggrapheneoxide-CuOasaprecursor.Remarkably,thedifferentnanocompositescouldbeformedjustbyvaryingthereactiontemperatureandtime.Thisworkprovidesafeasiblerouteforthepreparationofgraphene-basednanocompositeswithvariousconstituents.
简介:""Mensaytheyhatetoshop,""saysZhukin,CityUniversityofNewYorkSociology(社会学)professor.""Yetwhenyouaskthemdeeperquestions,itturnsoutthattheyliketoshop.Mengenerallyliketoshopforbooks,musicandhardware.Butifyouaskthemabouttheshoppingtheydoforbooksormusic,they'llsay,'Well,that'snotshopping.That'sresearch.'""
简介:Romanticismisanimportantstageintheevolutionofman’sself-consciousness.Itshowsnewinterestinandnewconcernwithmanandnature.Wordsworthiswell-knownasanaturepoet.Thethemeofhumanmindandnatureinhispoemshaslongattractedreaders’attention.However,hedoesnotindulgeinnatureitselfbuttakesitasconsolationandinspirationforhumankind.Inordertohighlightthepoet’sconcernwithhumanmind,thepresentpaperchoosestoexploreWordsworth’sconcernwithchildren’smind,basedontheanalysisofWordsworth’sThePreludeandmanyofhispoemsaboutchildren.