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500 个结果
  • 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:Thecombinationofboth4,4′-bipyridine(4,4′-bipy)anddihydrogenphosphateanionligandswithcopper(Ⅱ)resultsintheformationofanovellayeredcompoundCu(4,4′-bipy)2(H2PO4)2(H2O)2.ThecrystalstructurecomprisesdiscreteneutralCu(4,4′-bipy)2(H2PO4)2(H2O)2units.Thecopperatom,locatedonthecrystallographictwofoldaxis,iscoordinatedwithtwonitrogenatomsofterminal4,4′-bipyligandsandtwowatermoleculesattheequatorialpositions,andtwodihydrogenphosphateoxygenatomsattheaxialpositions,forminganelongatedoctahedron.Thecomplexisatwo-dimensionaldistortedrhomboidalnetworkpossessingtwokindsofrhomboidswithdimensionsofca.1.6792nm×0.3203nmand1.2778nm×0.3198nm,respectively.Thetwo-dimensionalnetworksarestackedparallellyoneachotheralongc-axistogiveanextendedthree-dimensionalchannelnetworkwithaninterlayerdistanceofca.0.5030nm.Crystaldata:triclinic,spacegroupP-1,a=1.0253(2)nm,b=1.4501(3)nm,c=0.79715(16)nm,α=97.91(3)°,β=90.99(3)°,γ=85.54(3)°,V=1.1703(4)nm3,Z=2,R=0.0892,wR=0.2451.

  • 标签: 磷酸盐 4 4'-双吡啶 铜(Ⅱ)复合物 沟渠构造 热液合成
  • 简介:Letq≥3beanoddnumber,abeanyfixedpositiveintegerwith(a,q)=1.Foreachintegerbwith1≤b2φ(q).ThemainpurposeofthispaperistostudythedistributionpropertiesofE(a,q),andgiveasharperhybridmean-valueformulainvolvingE(a,q)andgeneralKloostermansums.

  • 标签: D.H.Lehmer问题 错误条件 混合平均数公式 整数 对数
  • 简介:这份报纸关于一个参数依赖者接口地点为敏感的数字近似涉及精确、有效的计算算法的构造。在一根Euler-Bernoulli横梁上关于压电的致动器放置由敏感分析激发了,这个工作为兴趣的参数决定接口的地点的接口问题说明与敏感方程明确的表达有关的关键概念。第四个顺序模型问题被考虑的A,和为敏感计算的一个homogenization过程用标准有限元素方法被构造。数字结果证明敏感接口条件的合适的明确的表达和近似对获得会聚的数字敏感近似批评。第二命令椭圆形的接口模型问题也被提及,并且homogenization过程为这个模型简短被构画出。[从作者抽象]

  • 标签: 敏感性分析 计算问题 接口 二阶椭圆型方程 数值逼近 模型问题
  • 简介:Thevariationalprinciplesfor1-Dunsteadycompressibleflowinadeformingtubederivedinapreviouspaper^[1]areimprovedessentiallybyreconstructingtheinitial/final-integraltermsaccordingtoanewmethodsuggestedinarecentpaper[2],Asaresult,theinherentshortcomingofvariationalprinciplesofbeingunabletoadmitphysicallyrationalinitial/final-valueconditionsininitial/boundary-valueproblemsissuccessfullyeliminated.Thus,anewtheoreticalbasisforthetime-spacefinite-elementanalysisisprovided.

  • 标签: 一维不定常可压缩流体 变化规律 时间边界条件 流体力学 气体动力学
  • 简介:基于自然边界减小检验一个nonoverlapping领域分解方法。D-N的开发轮流出现的算法;为外面的球形的领域学习D-N方法的集中;D-N的分离形式的讨论轮流出现的算法。

  • 标签: DOMAIN DECOMPOSITION D-N Algorithm EXTERIOR ID
  • 简介:这份报纸为1-D板方程wtt+wxxxx+q处理锋利的observability不平等的问题(t,x)0边界与二打的w=调节w=wxx=0或w=wx=0,并且q(t,x)是一个合适的潜力。锋利的observability常数具有的作者表演订$\exp\left({C\left\|q\right\|_\infty^{\tfrac{2}{7}}}\right)$\exp\left({C\left\|q\right\|_\infty^{\tfrac{2}{7}}}\right)为q1。导出需要的observability不平等的主要工具是全球Carleman不平等,基于一个新点为第四个顺序板操作员的明智的不平等。

  • 标签: 不等式 可观测性 方程 D盘 夏普 边界条件
  • 简介:A3-DnonlinearproblemofsupercavitatingflowpastanaxisymmetricbodyatasmallangleofattackisinvestigatedbymeansoftheperturbationmethodandFourier-cosine-expansionmethod.Thefirstthreeorderperturbationequationsarederivedindetailandsolvednumericallyusingtheboundaryintegralequationmethodanditerativetechniques.Computationalresultsofthehydrodynamiccharacteristicsandcavityshapesofeachorderarepresentedfornonaxisymmetricsupercavitatingflowpastconeswithvariousapex-anglesatdiffer-entcavitationnumbers.Thenumericalresultsarefoundingoodagreementwithexperimentaldata.

  • 标签: supercavitating flow PERTURBATION METHOD NONLINEAR solution
  • 简介:Inthispaper,themultiplestochasticintegralwithrespecttoaWienerD’-processisdefined.AndalsoitisshownthatforaD’-valuednonlinearrandomfunctionalthereexistsasequenceofmultipleintegralkernelssuchthatthenonlinearfunctionalcanbeexpandedbyseriesofmultipleWienerintegralsoftheintegralkernelswithrespecttotheWienerD’-process.

  • 标签: WIENER valued stochastic expanded SEPARABLE LEMMA
  • 简介:以多酸阴离子簇为主体,选用2,6-二乙酰吡啶二缩氨基脲(DAPSC)为有机配体,在水热条件下,设计合成了新型的基于单钒取代的Keggin型多酸无机-有机杂化配合物[Ni(H2O)2(DAPSC)][H3SiW(11)VO(40)]·7H2O.单晶结构分析表明该化合物是零维结构,由平面型席夫碱修饰的多酸配合物.此外,通过元素分析、红外光谱、粉末X射线衍射、能谱分析等方法对其结构进行表征,并探索研究了其三阶非线性光学性质.

  • 标签: 多金属氧酸盐 吡啶-2 6-二酮二缩氨基 非线性光学
  • 简介:令R是有1的结合环,本文中给出R上某些2×2块阵的群逆的存在性及表示.

  • 标签: 块阵 群逆
  • 简介:Inthisarticle,theSm-dopingsinglecrystalsCa1-xSmxFe2As2(x=00.2)werepreparedbytheCaAsfluxmethod,andfollowedbyarapidquenchingtreatmentafterthehightemperaturegrowth.Thesampleswerecharacterizedbystructural,resistive,andmagneticmeasurements.ThesuccessfulSm-substitutionwasrevealedbythereductionofthelatticeparameterc,duetothesmallerionicradiusofSm3+thanCa2+.SuperconductivitywasobservedinallsampleswithonsetTcvaryingfrom27Kto44KuponSm-doping.ThecoexistenceofacollapsedphasetransitionandthesuperconductingtransitionwasfoundforthelowerSm-dopingsamples.ZeroresistivityandsubstantialsuperconductingvolumefractiononlyhappeninhigherSm-dopingcrystalswiththenominalx>0.10.Thedopingdependencesofthec-axislengthandonsetTcweresummarized.Thehigh-TcobservedinthesequenchedcrystalsmaybeattributedtosimultaneoustuningofelectroncarriersdopingandstraineffectcausedbylatticereductionofSm-substitution.

  • 标签: 掺杂晶体 超导电性 SM 单晶 晶格参数 淬火温度