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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:在这篇论文,我们学习在订的复制Hilbert空格和它的复制内核之间的关系。对多项式与领先的学期产生的二个伪不变的潜水艇空格的一个类似、单一的等价的完全的描述被给。

  • 标签: 子空间 不变式 数学理论 计算方法
  • 简介:Thispaperreportstwolanthanidecomplexesofformula(C9H7)Ln(C8H8)·(THF)2whereLnisProrNd,C9H7isindenyl,andC8H8iscyclooctatetraene(COT).ThecomplexeswerepreparedbythereactionofLnCl3withK(C9H7)andK2C8H8)inTHF.(C9H7)Pr(C8H8)·(THF)2crystallizesinTHFat-15℃inthemonoclinicspacegroupP21:withunitcelldimensionsa=8.446(0),b=10.083(2),c=13.407(3),β=105.48(1)°,V=1100.43(35)3,Dc=1.52g/cm3andZ=2.ThefinalRvalueis0.033,Rwvalueis0.030,respectively.In(C9H7)Pr(C8H8)·(THF)2afive-memberedringcentroidofC9H7,theC8H8ringcentroidandthetwooxygenatomsfromthetwoTHFmoleculesformadistortedtetrahedralgeometryaroundthemetal.

  • 标签: complexes monoclinic membered C8H8)Ln C8H8)Pr C9H7
  • 简介:作者在C上给围住的双线性的表格的Fourier变换的描述*(S1)×C*(二基础半的S2)以乔丹组织S1和S2*-representations,hemimogeneous随机域,并且象一样微弱地,harmonizable随机S回答1和S2直到Hilbert空格。

  • 标签: 双线性 半群 数学理论 计算方法
  • 简介:摘要刻画了|C(S)/L|≤2的完全正则半群S的同余格的具体特征,给出了具有上述性质的所有完全正则半群的分类.

  • 标签: 同余格 局部关系 分类
  • 简介:有N-(2-propionic酸)的新奇金轧(III)建筑群-salicyloylhydrazone(C10H10N2O4,H3L)并且1,10-phenanthroline(C12H8N2,phen)被准备并且描绘。水晶结构[Gd(H2L)(HL)-(H2O)3]2潲楰湯捩???慳楬祣潬汹?票牤穡湯??ㄠ??桰湥湡桴潲楬敮???????楢慯瑣癩瑩?

  • 标签: 邻二氮杂菲 晶体结构 X射线衍射 三斜晶系
  • 简介:<正>Inthispaper,weapplythesolitontheorytothecaseofisometricimmersionindifferentialgeometryandobtainafamilyofisometricimmersionsfromMn1(c1)×Mn2c2)tospaceformsMn(c)byintroducing2-parameterloopalgebra.

  • 标签: SOLITON THEORY ISOMETRIC immersion Riemaniann product
  • 简介:Thecrystalandmolecularstructuresof[(C3H7O)2PS2]2(CCDCNo.217201)weredeterminedbymeansofX-raycrystallography.ItcrystallizedinatriclinicsystemwithspacegroupP1^-andlatticeparametersa=0.82794(3)nm,b=0.84764(2)nm,c=0.85034(3)nm,α=97.78(3)°β=110.77(3)°,γ=94.95(3)°,V=0.54701(9)nm^3,Z=1.Inthismolecule,thetwodiisopropyldithiophosphategroups,[(C3H7O)2PS2]2,whichareparalleltoeachother,arelinkedbyanS--Sbondandthereexistinversioncentersinthemolecule,Inthestructure,theP=Sbondsinthetwodithiophosphateunitsaretrans-orientedtoeachother.

  • 标签: X射线结晶学 二烃基二硫代磷酸盐 中心对称 2 晶体结构 O'-二异丙基二硫代磷酸盐
  • 简介:Halfsandwichirondicarbonylcomplex[η5-C5H3(t-Bu)2]Fe(CO)2Cl(1)reactswith1,2-dilithiumdiselenocarboraneLi2Se2C2B10H10(2)togiveabinuclearironcarboranecomplex[η5-C5H3(t-Bu)2]2Fe2(CO)3*Se2C2B10H10(3).TheX-raydiffractionanalysisofcomplex3revealsthatoneoftheironatomsischiral.

  • 标签: Carborane Halfsandwich IRON complex Chirality Molecular
  • 简介:AnefficientmethodforC2nearlyarc-lengthparameterizedcurveispresented.Anideaofapproximationforthearc-lengthfunctionofparametriccurvewhichinterpolatesCADdatapointsisdiscussed.Theparameterizationisimplementedbyusingparametertransformation.Finally,twonumericalexamplesaregiven.

  • 标签: 单调保存插值 微分几何 参数曲线 弧长 积分公式
  • 简介:Theroleofpulseparametersonnanoparticlepropertyisinvestigatedself-consistentlybasedonacoupleoffluidmodelandaerosoldynamicsmodelinacapacitivelycoupledparallel-plateacetylene(C2H2)discharge.Inthismodel,themasscontinuityequation,momentumbalanceequation,andenergybalanceequationforneutralgasaretakenintoaccount.Thus,thethermophoreticforceariseswhenagastemperaturegradientexists.Thetypicalresultsofthismodelarepositiveandnegativeiondensities,electronimpactcollisionsrates,nanoparticledensity,andchargedistributions.Thesimulationisperformedfordutyratio0.4/0.7/1.0,aswellaspulsemodulationfrequencyfrom40kHzto2.7MHzforpureC2H2dischargesatapressureof500mTorr.Wefindthatthepulseparameters,especiallythedutyratio,haveagreataffectonthedissociativeattachmentcoefficientandthenegativedensity.Moreimportantly,bydecreasingthedutyratio,nanoparticlesstarttodiffusetothewall.Undertheactionofgasflow,nanoparticledensitypeakiscreatedinfrontofthepulseelectrode,wherethegastemperatureissmaller.

  • 标签: 脉冲参数 C2H2 纳米颗粒 凝固模拟 电容耦合 自放电
  • 简介:在CCSD(T)/6-311G(d,p)∥B3LYP/6-311G(d,p)水平上给出了反应C2H3+NO2的详细势能面信息,并列出了中间体和过渡态的几何构型.通过深入分析反应路径及反应机理,得到5个能量可行的产物和6条反应通道,其中产物C2H3O+NO的形成更有利,而产物CH2CO+HNO则是次要产物,其他产物在通常条件下可以忽略.

  • 标签: C2H3 NO2 反应势能面 乙烯自由基 过渡态 二氧化氮
  • 简介:应用量子化学从头计算和密度泛函理论(DFT)对HO2C2H2反应体系的反应机理进行了研究.在B3LYP/6-311G**和CCSD(T)/6-311G**水平上计算了HO2C2H2反应的二重态反应势能面.计算结果表明,主要反应方式为自由基HO2的H原子和C2H2分子中的C原子结合,经过一系列异构化,最后分解得到主要产物P1(CH2O+HCO).此反应是放热反应,化学反应热为-321.99kJ.mol-1.次要产物为P2(CO2+CH3),也是放热反应.

  • 标签: 密度泛函理论 HO2+C2H2 势能面 反应机理
  • 简介:Ourobjectivesweretodevelopanewchemicalmethodforthepolymerizationofpyrrole.CuCl2dissolvedinC2H5OHsolventisprimarilyusedfortheinitiationpolymerizationofpyrrole.ThepolymerswithdifferentyieldandconductivitywereobtainedbyraringtheinitialconcentrationofCu2+.TheinitialconcentrationsofCu2+variedfrom1.2×10-4moleto6.48×10-3moleCu2+with2.16×10-2molepyrrole.Thepolypyrroleobtainedwascharacterizedwithelementalanalyzer,XPS,IRspectroscopy,Four-pointprobeandSEM.

  • 标签: CuCl2-C2H5OH initiation SYSTEM Polymerization of PYRROLE
  • 简介:ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].

  • 标签: FIRST DIRECT MEASUREMENT