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303 个结果
  • 简介:Rareattentionhasbeenpaidtothecomparisonbetweenamonomeranditscorrespondingpolymerintermsoftheoptoelectroniccharacteristics.Inthisarticle,amodelH-shapedmoleculeanditscorrespondingpolymer,bothofwhichexhibitedsimilarpropertiesincludingblueemissionandsolutionprocessing,weredesignedandsynthesized.Optoelectronicpropertiesandvariouskindsofstabilityfeatures,includingthethermostabilities,spectralstabilitiesandamplifiedspontaneousemissioncharacteristicofthemonomerandpolymerwereinvestigated.Ingeneral,thecorrespondingpolymerPHexhibitedsimilaroptoelectronicpropertiesbutdeterioratedstabilitiescomparedwithitsH-shapedmonomerH-1probablyowingtothesimilarchemicalstructurebutthewidermolecularweightdistributionandmetalcatalystresidue.Importantly,monomerH-1displayedacomparableASEthresholdvaluewithitspolymerPH,suggestingthatH-shapedfluorene-basedsmallmoleculesmaybemorepromisingopticalgainmediainsolidstateamplifersandlasers.

  • 标签: FLUORENE H-SHAPE Stability OPTOELECTRONIC materials
  • 简介:Theorientationalorderoftwoliquidcrystals,namely,6-[4-(4-nitrophenylazo)phenyloxy]hexyldiethanolamines(C6)and10-1-bromo[4-(nitrophenylazo)phenyloxy]alkane(B10)wasstudiedbymeansof2HNMRspectroscopywithhexamethylbenzene-d18astheprobemolecule.TheresultsshowthatthedirectorsinthesmecticAphaseofC6andthenematicphaseofB10couldbealigned,whichwasparalleltothemagneticfield.TheorientationalorderparameterofthesolutemoleculesinC6wasabout0.2,whileitisonly0.1inB10,whichisexpectedbecausethemoreorderedsmecticphasetendstoalignsolutemoleculestoahighlevel.ComparedtotheorientationalorderparameterofthesoluteintheSmCphaseof4[3,4,5-tris(4-dodecyloxybenzyloxy)-benzoyloxy]-4-(4′-dodecyloxybenzoyloxy)biphenyl(Ⅰ)(P2=0.14),itislargerinSmAphaseofC6.TherelativelyhigherorientationalorderparameterofthesoluteinC6isattributedtotheformationofintermolecularH-bondsintheSmAphaseofC6.

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  • 简介:Theoneplusone(1+1)modeofhydrosilationreactionofladderlikecis-isotaticpolyallylsilsesquioxane(AllyI-T)andpolyhydrosilsesquioxane(H-T)usingdicyclopentadienylplatinumdichloride(Cp2PtCl2)asthecatalystleadstotheformationofanewpolyorganosiloxane(POS).ThepresenceofnanoscaletubularstructureintheproductPOSwaspreliminarilyprovedbyIR,1H-NMR,differentialscanningcalorimetry(DSC),X-raydiffraction(XRD),gelpermeationchromatography(GPC),atomicforcemicroscopy(AFM)andmolecularsimulation.

  • 标签: Hydrosilylation Polyorganosiloxane Self-assembly TUBULAR structure
  • 简介:TheauthorobtainsaWeierstrassrepresentationforsurfaceswithprescribednormalGaussmapandGausscurvatureinH3.AdifferentialequationaboutthehyperbolicGaussmapisalsoobtained,whichcharacterizestherelationamongthehyperbolicGaussmap,thenormalGaussmapandGausscurvature.TheauthordiscussestheharmonicityofthenormalGaussmapandthehyperbolicGaussmapfromsurfacewithconstantGausscurvatureinH3toS2withcertainalteredconformalmetric.Finally,theauthorconsidersthesurfacewhosenormalGaussmapisconformalandderivesacompletelynonlineardifferentialequationofsecondorderwhichgraphmustsatisfy.

  • 标签: 双曲空间 高斯映射 调和映射 WEIERSTRASS表示 曲率
  • 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:(连续)为电子结构的答案的计算的不同订单的有限元素近似在一些报纸被建议,这些途径的表演正在变得可估计并且现在很好被理解。在这份出版物,作者建议由联合有限元素网孔的精炼为完整潜力的电子结构计算扩大这discretization,在溶液随溶液主要是常规的区域的多项式近似的度的增加是很单个的的地方。近似性质的增加的这联合,做在一priori或一种posteriori方式,甚至当答案是单个的时,是著名的通常关于自由的度的数字生产最佳的指数的类型集中率。这里执行的分析在Hartree-Fock和Kohn假冒的问题的情况中支撑这个性质。

  • 标签: 有限元逼近 结构计算 电子结构 有限元网格 多项式近似 收敛速度
  • 简介:利用直接法合成未见文献报道的K8[ZnMg(H2O)W11O39]·15H2O,通过ICP,IR和XRD等方法对其结构进行表征,结果表明所合成的配合物具有Keggin结构.采用化学热扩渗法对合成配合物进行稀土扩渗实验,经XPS测试表明,有微量的钆渗进配合物的体相,并与组成元素存在键合作用,导电性测试结果表明,扩渗后试样的导电率提高10^5倍,是一种优良的固体电解质,有望成为具有实用价值的功能材料.

  • 标签: 多金属氧酸盐 稀土多元渗 导电性
  • 简介:Twooxo-vanadium(IV)complexes,[VO(C2O4)(2,2′-bipy)(H2O)]·C2H5OH(1)andVO(C2O4)(phen)(H2O)(2),where2,2′-bipy=2,2′-bipyridyl,phen=1,10-phenanthroline,weresynthesizedaspotentialfunctionalmodelsofvanadiumhaloperoxidases(VHPOs)inmixedsolventofethanolandwateratroomtemperature.Thecomplexeswerecharacterizedbyelementalanalysis,infrared(IR),UV-VisandX-raycrystallography.Structuralanalysesshowedthatvanadiumatomwascoordinatedbyaterminaloxygen,oneoxygenatomfromcoordinatedwater,twooxygenatomsfromthecarboxylategroupofoxalicacid,andtwonitrogenatoms(N1andN2)from2,2′-bipy/phen.Centralvanadiumatomsincomplexes1and2werebothinadistorted-octahedralenvironment,andsomeintermolecularhydrogenbondinglinkageswerealsoobservedineachcomplex.BrominationreactionactivityofthetwocomplexeswasevaluatedwithphenolredasorganicsubstrateinthepresenceofH2O2,Br-andphosphatebuffer,indicatingthattheycanbeconsideredasapotentialfunctionalmodelofVHPO.Inaddition,thermalanalysiswasalsoperformedanddiscussedindetail.

  • 标签: 过氧化物酶 模型化合物 结构表征 溴化反应 氧钒 仿生催化
  • 简介:在未采取预电离措施的情况下,研究了纯sf6气体及sf6/h29sf6/c2h6两种混合气体激光介质脉冲放电特性。实验结果表明,无预电离时SF68其混合气体介质可以实现自引发体放电,气体介质体放电维持电压主要由SF,;含量决定,C2H6具有抑制电弧的作用,可以有效延长体放电维持时间。分析认为,sf66体高折合场强E/P导致的放电通道电流密度受限和高电负度■引起的放电通道中负离子分解产生二次电子,是介质实现自引发体放电的重要机理。

  • 标签: HF激光 自引发 体放电 电弧放电
  • 简介:含有ONO给体原子的N-邻甲氧基苯甲酰基水杨酰肼配体与[VO(acac)2]在乙醇中反应得到钒(V)酰配合物VO[(C15H12N2O4)(OC2H5)].标题化合物晶体属三斜晶系,空间群Pī,晶胞参数:a=0.89411(5)nm,b=1.0063(2)nm,c=1.0392(2)nm,α=110.171(7)°,β=95.219(3)°,γ=93.822(2)°;V=0.8692(2)nm3,Z=2,R1=0.0513,wR=0.1532.研究结果表明:钒原子具有扭曲的四方锥配位构型,钒酰氧原子处在锥顶位置,配体的3个给体原子与溶剂分子形成锥底平面.

  • 标签: 配合物 | 合成 晶体结构 氧化还原 钒酰配合物
  • 简介:利用水热方法制备了一个新的过渡金属镉配合物[Cd(1,3-BDC)(L)(H2O)2]·H2O(1,3-H2BDC=间苯二甲酸,L=2-(3-吡啶基)-1H-苯并咪唑),并通过元素分析、红外光谱和X-射线单晶衍射方法确定了该配合物的晶体结构.结构分析表明该配合物属于单斜晶系,P21/c空间群,晶胞参数a=1.01641(6)nm,b=2.08842(12)nm,C=1.00l38(6)nm,β=106.3360(10)°,V=2.0398(2)nm3,Z=4,R1=0.0207,wR2=0.494.配合物中CdⅡ“离子与L配体的1个吡啶N原子、1,3-BDC的4个氧原子和2个配位水的O原子配位,形成七配位的扭曲十面体结构.配体1,3-BDC的桥连相邻的CdⅡ离子形成一维聚合物链,相邻链间通过氢键和π…π作用形成三维超分子网络,并对该配合物的热稳定性和荧光性质进行了研究.

  • 标签: 水热合成 配合物 晶体结构 超分子网络 荧光性质
  • 简介:SelectivelyconvertingCOandH2togasolineproduct(isoparaffinandolefin)inonestepstillremainsagreatchallenge.WedemonstrateeffectiveH-USYzeolitesupportednano-cobaltbifunctionalcatalystsforthiscatalyticreaction,whicharepreparedbythenovelphysicalsputteringprocess.Particlesofthesputteredcobaltexistinnano-levelandarewell-dispersedonacidUSYzeolite.Easyactivationoftheloadednano-cobaltisalsoachievedinalow-temperaturehydrogenreductionatmosphere.Inthetandemcatalyticreaction,thesputteredbifunctionalCo/USYcatalystexhibitsamuchhigherCOconversionandhigherisoparaffinselectivitythantheconventionalimpregnatedone.ComparedwithH-Mor,H-Betaandotherzeolitessupportedcatalysts,H-USYzeolitesupportedcobaltcatalystshowstheclearestpromotionaleffectontheactivityofFischerTropschsynthesis.Thedescribedsynthesishereinprovidesanewpathwaytosolvetheproblemcausedbythestrongmetal-supportinteraction(MSI)inheterogeneouscatalysis.

  • 标签: USY沸石 CO转化率 钴催化剂 溅射工艺 纳米级 合成气
  • 简介:介绍h--有限元素方法在混合变化明确的表达之上基于为的p三地司烧方程和线性化的非牛顿的流动。从问题H产生的代数学的系统的计算[潜水艇h];方法论;结果和讨论。

  • 标签: Mired hp- FINITE element method Non-Newtonian
  • 简介: ̄1HAND ̄(13)CNMRSTUDYOFINCLUSIONCOMPLEXATIONOFDSSWITHβ-CYCLODEXTRIN¥QingXiangGUO;TanREN;ZiZhongLIandYouChengLIU(NationalLabora...

  • 标签: 13C NMR
  • 简介:Inthispaper,weinvestigatethefiniteelementA-φmethodtoapproximatetheeddycurrentequationswithdiscontinuouscoefficientsingeneralthree-dimensionalLipschitzpolyhedraleddycurrentregion.Nonmatchingfiniteelementmeshesontheinterfaceareconsideredandoptimalerrorestimatesareobtained.

  • 标签: 涡电流 有限元法 误差评估 不匹配网格
  • 简介:对凸角域上的Neumann问题△u+au=finΩ,эu/эn=0onэΩ,这里α≥0是Ω上的有界可测函数且不恒为0,我们证明了:若f∈L^2(Ω),则解u∈H^2(Ω),且有正则性估计‖u‖2.0≤C‖f‖0.Ω。

  • 标签: 凸角域 椭圆方程 NEUMANN问题 正则性 Euler型方程
  • 简介:PhotocatalyticH2productionhasemergedasoneofthemostcleanandpromisingrenewableenergysources.InspiteoftheeffortstoobtainefficientphotocatalystsabletoproduceH2fromSunlightandwater,thereisstilltheneedtopreparecheaperandenvironmentalfriendlierphotocatalysts.Phosphatebasedmaterialscouldbegoodcandidatestofulfilltheserequirements.InthismanuscriptwehavepreparedasetofmixedTi3+/Ti4+valence,open-frameworktitaniumphosphates(of-TiPO4)andmixedtitaniumoxide/phosphatederivatives(cr-TiP),correlatingtheirstructureandcompositionwiththephotocatalyticactivityforH2production.Wedeterminedthatmixedtitaniumoxide/phosphatecrystallinephasesproducedenhancedH2evolutionunderSunsimulatedlightirradiationthanmixedTi3+/Ti4+valence,open-frameworktitaniumphosphatesandtitaniumoxidephases.

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