简介：ItwasshownbyTEMandX-rayanalysisthatNi3AlisthemainphaseoftheintermetallicsynthesizedundercompressionfromthepowdermixtureofNiwithAlalloyedbyB.TheNi3Bisasecondaryphase.ThevalueofthelatticeparameteroftheintermetallicNi3AlwithandwithoutBincreaseswhentheconcentrationofAlincreases.TheincreaseinAlconcentrationfrom23.5to25.0intheinitialpowdermixtureleadstodecreasingthesolubilityofBintheNi3Alphase.

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简介：Manganesephthalocyanine(MnPc)-Fe3O4nanoparticlescompositewaspreparedandcharacterized.TheresultsshowthatMnPcarecompletedonthesurfaceofFe3O4nanoparticlesinthestateofsinglemolecule.ThereiseffectivecompositebetweenMnPcandFe3O4nanoparticleswhichcanimprovetheantioxidizationabilityofFe3O4nanoparticlesgreatly.Thecompositewasdispersedintochlorinatedparaffinoiltoformelectromag-netorheological(EMR)fluidwithhighactivity,andtheEMRpropertiesofthisEMRfluidarestudied.

简介：ThemechanismoftheinterfacialreactionofAl2O3/mediumMnsteelcontainingNbwasstudiedbymeansoftheobservationontheinterfacialreactionphenomenonofAl2O3/mediumMnsteel,andtheanalysesontheinterracialphases.TheresultsshowthatwhenT≥1550℃,theinterfacialreac-tionofAl2O3/mediumMnsteelcontainingNbhappened.InthemediumMnsteelmatrix,NbexistsintheformofNbC.NbCarethenucleatingbaseofCOgasbubbles.

简介：ThepiezoelectriccompositescontaininghighlyorientedBaTiO3whiskersasactivephaseandPVDFasmatrixhavebeenpreparedbymicro-holeextrusionandorientationincarriedfibers.ThemorphologyoforientedBaTiO3whiskersandmicrostructureofthecompositeswereobservedbySEM.Asforitselectromechanicalproperties,itisfoundthatthedielectricconstant,piezoelectricconstantandremnantofpolarizationintheBaTiO3whisker-PVDFcompositeareconsiderablyhigherthanthatintheBaTiO3powders-PVDFcomposite,whilethelossfactorsfollowtheoppositetrend.FortheBaTiO3whisker-PVDFcomposite,thevaluesofε,d33andPrparalleltothewhiskerorientation(normalspecimen)aremuchhigherthanthatperpendiculartothewhiskerorientation(parallelspecimen).Thesignificanteffectsoftheconnectivepassagesofactivephaseonelectromechanicalpropertiesofthepiezoelectriccompositeshasalsobeeninvestigated.

简介：BaTiO3/PVDFnanocompositeswerepreparedviain-situgrowthofnanosizedBaTiO3particlesinPVDFmatrixbyusingthesolgelmethod.ThepresentelementsofBaTiO3/PVDFnanocompositeswereana-lyzedbyanelectronprobeX-raymicroanalyser.NanosizedBaTiO3growninthecompositefilmswascharacterizedbyanX-raydiffractometerandatransmissionelectronmicroscope,andthedielectricpropertiesofthecompositefilmsweremeasured.ThedistributionofBaTiO3nanoparticlesin-situgrowninthePVDFmatrixwasexaminedus-ingascanningelectronmicroscope.

简介：Theimplantedionrange,thedepthprofileandthefilmsttuctureoftheimplantedlayerwerestudied;thecarrierconcentrationandthemobilityweremeasured;theconductivitymechanismofthefilmimplantedFeintoAl2O3ceramicwasdiscussed.TheconclusionisthattheimplantedFe2+ionsmoveintoAl2O3latticeandreplaceAl3+toformsubs-titutionimpuritiessothattheionimplantedlat-tice,ascomparedwiththeoriginalone,presentsaneffectivenegativechargewhichformsanegativechargecenter.Avacancyisboundarroundit,andanacceptorisintroducedintheforbiddenband.

简介：著名的徕卡公司于1976年9月在摄影器材展览会上推出了新型单反相机R3,引起大家的关注。众所周知,在此之前的徕卡单反相机机身有Leicaflex,LeicaflexSL,LeicaflexSL2,都是机械快门,并且技术上的进步比较缓慢。而新一代相机R3则是徕卡的第一架采用了电子快门的机种,并采用了当时最先进的电子技术。电子快门由1/1000秒到4秒连续工作,具备光圈优先功能,并具有1/90秒的T门。优雅的线条,敏捷的

简介：采用低温固态反应合成了一系列BaTi1-xZrxO3固溶体纳米粉末（0≤X≤0．3）。经XRD证明，产品为立方晶系的完全互溶取代固溶体。TEM形貌观察，粒子为均匀球形，平均粒径70nm。通过制陶实验，分别测定了该系列固溶体的室温介电常数、介电损失。结果发现，采用低温固态反应在BaTiO3中掺入适量锆以后，室温介电常数由纯钛酸钡的3000提高到8600，而介电损失却下降了一半。

简介：Basedonrigid-plasticfiniteelementmethod,askewrollingprocessofsteppedpartissimulated.Consideringnodesavingandeffectiveremeshing,thetetrahedronsolidelementsareusedtodiscreteworkpiece.Theworkpiecematerialadoptsrigid-plasticmodel,wheretheflowstressisfunctionofeffectivestrain,effectivestrainrateandtemperature.Thethermomechanicalcouplingisconsideredinthesimulation.Tomodelthespinningworkpieceundergoingplasticdeformation,anovelsolutionispresentedandappliedinthispaper.Thestressstateintheworkpieceandformingcharacteristicofskewrollingareanalyzed.Theformingload,includingrollertorqueandforcesinthreedirectionsarepredicted.Theaboveanalysesarehelpfultounderstandingofformingmechanismsandimprovingofprocessanddiedesign.

简介：采用柠檬酸作为改性剂来改性纳米Fe3O4磁性颗粒，成功研制成溶胶颗粒（粒径为40nm左右），饱和磁化强度为0．84emμ／g的水基Fe3O4磁性液体。重点探讨了pH值、改性剂用量、改性温度对改性效果的影响，优化出改性温度为80℃，pH值范围为4．5-6．5等的最佳制备工艺条件；采用透射电镜、红外、紫外可见光分光光度计等分析方法对核壳式结构的粒子尺寸、形貌及其化学组成成份等进行了测试表征。

简介：Thewidthandspacingofadiabaticshearbands(ASBs)intheserratedchipsgeneratedduringhighspeedorthogonalcuttingof30CrNi3MoVstructuralsteelweremeasuredbyopticalmicroscopy(OM),thetemperatureriseintheshearbandwasestimated.ThemicrostructuresoftheASBswerealsocharacterizedbySEMandTEM.TheresultsshowthatthewidthandspacingofASBsdecreasewiththeincreaseofthecuttingspeed.ThefurtherobservationsshowthatthemicrostructurebetweenthematrixandthecenteroftheASBgraduallychanges,andthatthemartensiticphasetransformation,carbideprecipitationandrecrystallizationmayoccurintheASB.

简介：Ca_3Co_2O_6，Na和Ni的电子结构做了模型被被基于的Camhride连续全部的精力包裹(CASTEP)的量化学药品软件学习，在密度函数理论(DFT)和伪潜力上。优点(Z)的电子传导性，seebeckcoefficient，热传导性和图被计算。精力乐队结构在做semiconductors.Na的模型shoivs由于代理杂质揭示杂质层次的形式p类型半导体的特性，而是做Ni的模型是n-typesemiconductor。计算结果证明做的模型的电的传导性比的高非--做的模型，当Seebeck系数和做的模型的热电导率是比非做的那些低的时。因为大增加，电的电导率，做Na的模型的Z被提高，热电的性质被改进。作为Seebeck系数的大衰落，在另一方面，Ni-的Z做了模型不到的非--做的模型。

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简介：PbTiO_3/PVDFnanocomposites被准备经由在原处在由大音阶的第五音胶化的PVDF矩阵的nanosizedPbTiO_3粒子的生长方法。种的NanosizedPbTiO_3，在composites，电影被X光检查衍射学(XRD)描绘，准备的合成电影的传播电子显微检查法，和介电性质被测量。在原处在PVDF矩阵种的PbTiO_3nanoparticles的分发用亲戚介电常数与增加PbTiO_3in-situgrown的重量分数增加的扫描电子显微镜.The被检验。特别地，介电损耗monotonically随PbTi-O_3的增加减少，在1MHz的内容。

简介：自从摩托罗拉公司在一年前发布其超薄手机RAZR以来，其他手机制造商也纷纷效仿其超薄风格及时尚的设计——不过多以失败告终。RAZR是如此地受人欢迎，时至今日在全球的销量已超过1200万台。最新加入RAZR队列的非3G手机是V3i。

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简介：尼康FM3A自发布到上市一直在摄影界制造轰动,“新浪摄影论坛”、“色影无忌”等和摄影有关的论坛中的热门话题都是围绕它而展开的,很多和摄影有关的报刊杂志也是如此。至今大家还在探讨要不要买它?为了能给大家一些帮助,本人根据有关资料编译此文,供购机者参考。

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简介：Anovelsolubleπ-conjugatedpolymer,poly[(3-acetylpyrrole-2,5-diyl)p-(N,N-dimethylamino)azobenzylidene](PAPDMAABE),wassynthesizedbycondensationof3-acetylpyrrolewith4-aldehyde-4'-dimethylaminoazobenzene(ADMAA).ThechemicalstructureofPAPDMAABEwascharacterizedbyFouriertransforminfraredspectroscopy(FTIR),1H-NMR,andUV-Vis-NIRspectra.Transmissionelectronmicroscope(TEM)analysisforPAPDMAABEindicatesthatpartofPAPDMAABEisincrystalstate,duetotheshort-rangeorderofthepolymer.Thermogravimetricanalysis(TGA)curveshowsthatthepolymerhasgoodthermalstabilityanditsdecompositiontemperatureis248℃.TheopticalbandgapofPAPDMAABEobtainedfromtheopticalabsorptionspectrumisabout1.73eV.Theresonantthird-ordernonlinearopticalpropertyofPAPDMAABEat532nmwasstudiedusingdegeneratefour-wavemixing(DFWM)technique.Theresonantthird-ordernonlinearopticalsusceptibilityofthepolymerisabout7.48×10-8esu.