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491 个结果
  • 简介:Inthispaper,weintroducethereducedmatrixinkqrepresentationandprovidethereducedmatrixelementsofaprojectionoperatorPontherationalnoncommutativeorbifoldT2/Z4.wegivetheclosedformfortheprojectorbyJacobiellipticalfunctions.Sinceprojectorscorrespondtosolitonsolutionsofthefieldtheoryonthenoncommutativeorbifold,wethuspresentacorrespondingsolitonsolution.

  • 标签: 投影算子 非交换 JACOBI椭圆函数 理性 矩阵元素 封闭形式
  • 简介:与飘移散开(DD)的联合使用模型,试验性的测量参数和小信号的正弦曲线不变的分析,我们为4H-SiC提取Y参数埋葬隧道的金属氧化物半导体域效果晶体管(BCMOSFET)。输出电线走火水流获得G,梅森的不变的U分别地在普通来源的配置f(T)和摆动f(最大)的最大的频率为外推的统一水流获得频率被计算。这里f(T)=800MHz和f(最大)=5GHz为4H-SiCBCMOSFET被提取,当地效果活动性到达它的山峰时,珍视87cm(2)/Vs什么时候V-GS=4.5V。模拟结果清楚地证明4H-SiCBCMOSFET和地效果活动性的典型频率是优异的,由于新奇结构,与常规MOSFET相比。

  • 标签: 移动扩散模式 稳定状态分析 参数变化 4H-SIC
  • 简介:Firstly,theRiemannboundaryvalueproblemforakindofdegenerateellipticsystemofthefirstorderequationsinR~4isproposed.Then,withthehelpoftheone-to-onecorrespondencebetweenthetheoryofCliffordvaluedgeneralizedregularfunctionsandthatofthedegenerateellipticsystem’ssolution,theboundaryvalueproblemasstatedaboveistransformedintoaboundaryvalueproblemrelatedtothegeneralizedregularfunctionsinCliffordanalysis.Moreover,thesolutionoftheRiemannboundaryvalueproblemforthedegenerateellipticsystemisexplicitlydescribedbyusingakindofsingularintegraloperator.Finally,theconditionsfortheexistenceofsolutionsoftheobliquederivativeproblemforanotherkindofdegenerateellipticsystemofthefirstorderequationsinR~4arederived.

  • 标签: 退化椭圆型方程 黎曼边值问题 广义正则函数 椭圆系统 奇异积分算子 一阶方程
  • 简介:磁铁矿(Fe3有不同尺寸和形状的O4)nanoparticles被热分解方法综合。二条途径,非注射一个壶和热注射的方法,被设计详细调查生长机制。nanoparticles的尺寸和形状被调整先锋集中和持续时间时间决定,这被发现,它能好在我们的合成系统基于LaMer模型由机制解释了。monodisperseFe3O4nanoparticles从5nm有一条吝啬的直径到16nm,和形状进化从对球形三角形、立方。磁性是尺寸依赖者,和Fe3在关于在房间温度和最大的浸透磁化的5nm展览superparamagnetic性质的小尺寸的O4nanoparticles来临到78emu/g,而Fe3O4nanoparticles当直径增加到大约16nm时,开发铁磁性的性质。

  • 标签: 纳米FE3O4 磁性纳米粒子 合成系统 单分散 FE3O4纳米粒子 可控
  • 简介:MoleculardynamicssimulationsareperformedtostudythegrowthmechanismofCH4-CO2mixedhydrateinxCO2=75%,xCO2=50%,andxCO2=25%systemsatT=250K,255Kand260K,respectively.OursimulationresultsshowthatthegrowthrateofCH4-CO2mixedhydrateincreasesastheCO2concentrationintheinitialsolutionphaseincreasesandthetemperaturedecreases.Viahydrateformation,thecompositionofCO2inhydratephaseishigherthanthatininitialsolutionphaseandtheencagingcapacityofCO2inhydratesincreaseswiththedecreaseintemperature.ByanalysisofthecageoccupancyratioofCH4moleculesandCO2moleculesinlargecagestosmallcages,wefindthatCO2moleculesarepreferablyencagedintothelargecagesofthehydratecrystalascomparedwithCH4molecules.Interestingly,CH4moleculesandCO2moleculesfrequentlyreplacewitheachotherinsomeparticularcagesitesadjacenttohydrate/solutioninterfaceduringthecrystalgrowthprocess.Thesetwospeciesofguestmoleculeseventuallyacttostabilizethenewlyformedhydrates,withCO2moleculesoccupyinglargecagesandCH4moleculesoccupyingsmallcagesinhydrate.

  • 标签: 分子动力学模拟 水合物 CO2 CH4 混合 二氧化碳浓度
  • 简介:Anovelflower-likehydratedmagnesiumcarbonatehydroxide,Mg_5(CO_3)_4(OH)_2·4H_2O,withmicro-structurecomposedofindividualthinnano-sheetswassynthesizedusingafacilesolutionroutewithouttheuseoftemplateororganicsurfactant.Reactiontimehasanimportanteffectonthefinalmorphologyoftheproduct.Themicro-structureandmorphologyofMg_5(CO_3)_4(OH)_2·4H_2OwerecharacterizedbymeansofX-raydiffractometry(XRD),field-emissionscanningelectronmicroscopy(FE-SEM).Brunauer-Emmett-Teller(BET)surfaceareasofthesampleswerealsomeasured.Theprobableformationmechanismofflower-likemicro-structurewasdiscussed.ItwasfoundthatMg_5(CO_3)_4(OH)_2·4H_2Owithflower-likemicro-structurewasanovelandefficientcatalystforthesynthesisofdiphenylcarbonate(DPC)bytransesterificationofdimethylcarbonate(DMC)withphenol.

  • 标签: 碳酸镁氢氧化 合成 微观结构 催化活性 酯交换反应
  • 简介:首先研究制备了Fe3O4和SO4^2ˉ-TiO2固体酸催化剂,在此基础上采用共沉淀和浸渍的方法制备了磁性和超细SO4^2ˉ-TiO2-Fe3O4固体酸催化剂。利用XRD,TEM和FT—IR等分析测试手段对催化剂的结构和性能进行了表征。测定结果证实该催化剂具有较小的粒度,较高的磁性表现。在乙酸丁酯合成反应中SO4^2ˉ-TiO2-Fe3O4展示了很高的催化活性(酯化率可达82.7%),而且利用Fe3O4的磁性可对催化剂进行分离和回收.

  • 标签: 磁性 纳米 固体酸 催化剂
  • 简介:氧化物PbMn(SO4)的磁性2由通过SO4tetrahedra与对方一起连接了的MnO6octahedra组成了,很好在实验被学习。在这篇论文,我们探索了它的有趣电子并且有第一原则的计算的磁性。也就是,我们Mn离子高有的所有旋转的结果表演说S=5/2,并且在NN和NNN之间的磁性的couplings是antiferromagnetic,它与试验性的结果同意很好。而且,吃惊在NN和NNN之间的相互作用最优地与扩大H被解释的旋转交换结果

  • 标签: 物理学 理论 现状 发展
  • 简介:ThefutureGSIOnline-Offline-Object-OrientedanalysisframeworkGo4basedonROOT[CERN,R.Brunetal]providesamechanismtomonitorandcontrolananaluysisatanytime.ThisisachievedbyrunningtheGUIandtheanalysisindifferenttasks.Tocontrolthesetasksbyonenon-lbockingGUI,theGo4TaskHandlerpackagewasdeveloped.Itoffersanasynchronousintertaskcommunicationviaindependentchannelsforcommands,data,andstatusinformation,Eachchannelisprocessedbyadedicatedthreadandhasabufferqueueasinterfacetotheworkingthread.ThethreadsarecontrolledbytheGo4ThreadMAanagerpackage,basedontheROOTTThreadpackage,InparalleltotheGUIactions,theanalysistaskscandisplayobjectslikehistogramsintheGUI.AtestGUIwasimplementedusingtheQtwidgetlibrary(TrolltechInc.).AQttoROOTinterfacehasbeendeveloped.TheGo4packagesmaybeutilizedforanyROOTapplicationthatrequirestocontrolindependentdataprocessingormonitoringtasksfromanon-blockingGUI.

  • 标签: 高能物理实验 数据处理 控制
  • 简介:ThepossiblegeometricalstructuresandrelativestabilitiesofsemiconductormicroclustersGa.P.(n=1-4)werestudiedbyvirtueofdensityfunctionalcalculationswithgeneralizedgradientapproximation(B3LYP).ForthemoststableisomersofGa,,P.(n=1-4)clusters,theelectronicstructure,vibrationalproperties.dipolemoment,polarizabilityandionizationpotentialwereanalyzedbymeansofHF.MP2.CISDandB3LYPmethodswithdifferentbasissets.

  • 标签: 半导体 磷化镓 电子结构 稳定性 偶极矩 振动性能
  • 简介:Thecrystalstructureof[Ni(TAAB)(py)2](BF4)2,whereTAABisthetetradentatemacrocyclicligandtetrabenzo[b,f,j,n][1,5,9,13]tetraazacyclohexadecine,hasbeendeterminedfromX-raydiffractionanalysis.Thecrys.taibeiongstomonoclinic,spacegroupP21/nwithcellparameters

  • 标签: MONOCLINIC shaped BRIDGED PYRIDINE BENZALDEHYDE editorial
  • 简介:新奇tetra-carboxylphenyl杯的相互作用[4]有牛的心细胞色素c(Cc)的arene(TCPC)被荧光光谱学和分子的建模方法首先调查。稳定的1:1建筑群的形成被荧光滴定监视,并且它的有约束力的常数是1.916脳107L摩尔?1。分子的建模揭示TCPC的识别机制到Cc表面,也就是说,静电的相互作用驾驶TCPC到Cc表面,并且货车derWaals相互作用面向TCPC平行到Cc劈开。

  • 标签: 蛋白质表面识别 荧光光谱学 分子模型 细胞色素
  • 简介:Underdifferentreactionconditions,theexpectedandunexpectedreactionproducts(ofwhichX-raycrystallographicstructurewaspresented)ofetherificationof2-per(poly)fluoroethyl4-substitutedphenolwithβ-haloethanolcanbeobtainedrespectively.

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  • 简介:Thecellulosetris(4-methylbenzoate)hasbeensynthesisedbythecatalyticmethodandwassupportedatGasChromQ.Theabsorptioncapabilityofcellulosetris(4-methylbenzoate)usedasagaschromatographicstationaryphasewascharacterizedbychromatographicmethodandtheClausius-Clapeyronequation.However,n-alcohols(C1-C8)weresuccessfullyseparatedonthecolumnpackedwithGasChromQcoatedwithcellullosetris(4-methylbenzoate).

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