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489 个结果
  • 简介:CyclicvoltammetryandchronoamperometrywereusedtoinvestigatetheclectrochemicalbehaviorofFe(Ⅱ)andEr(Ⅲ)inaLiClO4-DMSO(dimethylsufoxide)systematPtandCuelectrodes.ExperimentalresultsindicatethatthereductionsofFe(Ⅱ)toFe(0)andEr(Ⅲ)toEr(0)wereirreversibleatPtandCuelectrodes.ThediffusioncoefficientandtheclectrontransfercoeffieientofFe(Ⅱ)ina0.01mol/LFeCl2-0.1mol/LLiClO4-DMSOsystemat303Kwere1.70×10^-10m^2/sand0.08respectively,thediffusioncoeffieientandtheelectrontransfercoefficientofEr(Ⅲ)ina0.01mol/LErCl3-0.1mol/LLiClO4-DMSOsystemat303Kwere1.47×10^-10m^2/sand0.108respectivealy.Thehomogeneous,strongadhesiveEr-FealloyfilmscontainingErof31.39%-42.12%inmassfractionwithmetalliclustrewerepreparedbypotentiostaticelectrolysisonaCuelectrodeinaErCl3-FeCl2-LiClO4-DMSOsystemat-1.75—-2.05V(vs.SCE).

  • 标签: 铒钫合金 薄膜 二甲亚砜 循环伏安法 计时安培分析法 电化学
  • 简介:[1]BASFUSP4479906[2]BASFBP1443541[3]BASFDE3618265[4]WangL.,WuZ.,ChinaLeather,26(8),11,(1997)[5]YuanL.,DinY.,ChineseChemistryBulletin,(2),19(1988)[6]KurokiH.,ChemistryofDyeingTheory(ChineseTranslation),TextileIndustryPress,Beijing,89(1982)[7]WangS.,LiP.,WuZ.DyestuffIndustry(Chinese),34(4),1,(1997)[8]Tian,Y.,Wu,Z.,Wang,G.,Zhang,S.J.ChineseChem.Eng.,46,156(1995)[9]Tian,Y.,Wang,G.,Wu,Z.,J.ChineseChem.Eng.,47,75(1996)[10]Lycka,A.,DyesandPigment,32,11(1996)[11]Griffith,J.,ColourandConstitutionofOrganicMolecules,AcademicPress,London,191(1976)

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  • 简介:Dibromobiphenylreactedwithcynomethylanioninammoniaunderirradiationtoformnucleophilicbis-substitutedproductinhighyieldwithoutsubstantialmonosubstitutedproduct.Quantumyieldsfortheformationsofbis-andmonosubstitutedproductswerefoundtobe85.6and2.3×10-6respectively,whilethecorrespondingpseudo-first-orderrateswere6.9×10-3and5.2×10-10mol.L-1.S-1.Blockupthepossibleelectrontransferof4-brome-4’-cyanomethylbiphenylylradicalanionto4-cyanometbyl-biphenylylradicalandbromineion.

  • 标签: PHOTOCHEMISTRY SRN1 REACTION electron TRANSFER dibromobiphenyl.
  • 简介:Ahomologousseriesof4’-methylphenyl4"-[(4-alkoxy-2,3,5,6-tetrafluorophenyl)ethynyl]-benzoateshavebeensynthesized.Polarizingmicroscopictexturalobservationshowsthatsuchcompoundsexhibitenantiotropicnematicphase.

  • 标签: Liquid crystal 1 4-tetrafluorophenylene SYNTHESIS NEMATIC
  • 简介:Weexperimentallydemonstratea4×4nonblockingsiliconthermo-optic(TO)switchfabricconsistingofthreestagesoftunablegeneralizedMach–Zehnderinterferometers.All24routingstatesfornonblockingswitchingarecharacterized.Thedevice’sfootprintis4.6mm×1.0mm.Measurementsshowthattheworstcrosstalkofallswitchingstatesis-7.2dB.Theon-chipinsertionlossisintherangeof3.7–13.1dB.TheaverageTOswitchingpowerconsumptionis104.8mW.

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  • 简介:Thesynthesisofopen-fiameworkmetalphosphateshasbeenasubjectofintenseresearchowingtotheirinterestingstructuralchemistryandpotentialapplicationsasionexchangers,catalystsandadsorbents.Alargenumberofthesematerialsaresynthesizedinthepresenceoforganicaminesasstructure-directingagents.Recently,manyresearchactivitieshavefocusedonthesynthesisofinorganic-organichybridframeworks.Ascomparedwithinorganicligands,theadvantageofusingorganicmultidentateligandsistheefficacyofrationaldesignofcrystallinesolidsthroughtheircoordinatingpropensitiesandgeometries.

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  • 简介:Thesynthesisandphasebehaviorofaseriesof4’-alkyloxy-4-hydroxybiphenylswerediscribed.Theeffectsofreactionconditionsontheyieldsofproductswereinvestigated.Thecharacterizationsofthermotropicliquidcrystallineproductsforthetypeandthermalpropertiesarediscussedthroughtheuseofdifferentialscanningcalorimetry,polarizingmicroscopy.

  • 标签: crystalline ATTRACTIVE spectrometer PHOTOGRAPH CALORIMETRY melting
  • 简介:Reactionsofthe6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrilederivative1withα-halo-carbonylcompoundsgavetheortho-substitutedintermediates2a-cwhichwereconvertedintofuro[2,3-b]thiopyrano[4,3-d]pyridines3a-cbyfusionofafuranmoietyunderbasicconditions.Furthercyclizationof3a-cledtoafusionofapyrimidinering,yieldingthetetracyclicproducts6,7and8.Inaddition,condensationof6withvariousaromaticaldehydesaffordedthecorrespondingimines9a,b.Mannichreactionof7gaveproducts10a,b.

  • 标签: Synthesis AROMATIC ALDEHYDES products MANNICH reaction
  • 简介:Thestructureofpolyimidefrom1,4-bis(3’,4’-dicarboxyphenoxy)benzeneand4,4’-oxydianilinefilmspecimensbeforeandafterhotstretchinghasbeeninvestigatedbyWAXD,DSCandFTIR.AsevidencedbyboththeWAXDandDSCresults,itcouldbebelievedthatstraininducedcrystallizationdidtakeplaceafterhotstretching.Meanwhile,shiftingpositionandsplittingofsomebandpeaksexistedontheFTIRspectrogramswereexplainedintermsoftheclosepackingofchainsandthechangesofinter-molecularcharge-transferinteractionbetweenimidegroupsandaromaticgroupsuponcrystallization.

  • 标签: POLYIMIDE ORIENTATION CRYSTALLIZATION FTIR
  • 简介:3,5,6,8-Tetrahydro-4H-thiopyrano[4′,3′:4,5]thieno[2,3-d]pyrimidin-4-ones(7)weresynthesizedviathebasecatalyticreactionsofaminesorphenolswithcarbodiimides(5),whichwereobtainedfromtheaza-Wittigreactionsofiminophosphoranes(4)witharomaticisocyanates.

  • 标签: 反应合成 膦亚胺 四氢 噻吩 嘧啶 碳二亚胺
  • 简介:On △I= Bifurcation PhenomenaOn△I=BifurcationPhenomena¥ZhangJingye;YangSunandMikeGuidryTheexperiments-bythenew7--raydetector...

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  • 简介:我们介绍自发的对称碎在Pati之间的acouplingbetween的顺序—Salam和电镀物品弱对称苏(4)_(PS)直接X苏(4)_(EW)可伸缩以便在宏大统一精力在联合常数之中建立一种算术地一致的关系。与减已知的夸克和雷普顿的雷普顿量数字那里的酒吧的价值,由传递includingright的中微子,我们能在直到电磁的U(1)_(他们)的层次放大的不同精力发现混合角度关系。

  • 标签: 电弱模型 统一化对称 规范对称 耦合常数
  • 简介:Emissionquenchingof[Ru(bpy)2(4,4’-dcbpy)](PF6)2(1)bybenzenamine,4-[2-[5-[4-[4-dimethylamino]phenyl]-4,5-di-hydro-1-phenyl-1H-pyrazol-3-yl]-ethenyl]-N,N-dimetyl(2)or1,5-diphenyl-3-(2-phenothiazine)-2-pyrazoline(3)wasobserved.Measurementsoftheemissiondecayof1beforeandafteradditionof2or3bysinglephotoncountingtechniquecon-finnedtheobservations.Theemissionquenchingof1by2or3wassubmittedtoStern-Volmerequation.Itwascalculatedthatthequenchingrateconstants(kq)are5.5×109(mol/L)-1s-1for2and4.0×109(mol/L)-1s-1for3,respectively.Theseresultsindicatedacharacterofdynamicquenchingprocess.Thesinglet-stateof2or3wasalsoquenchedby1.ThequenchingbehaviorsdidnotconformtotheStern-Volmerequationandinvolvedbothstaticanddynamicquenchingprocesses.Theapparentquenchingrateconstant(kapp)wascalculatedtobe3×109(mol/L)-1fortheinteractionofexcited2with1,and1.2×109(mol/L)-1forthatofexcited3wit

  • 标签: RUTHENIUM COMPLEXES PYRAZOLINE compounds electrontransfer dynamic
  • 简介:Therearemoreandmorecountriestoakeanefforttothestudiesofvanadiumalloyforfusionapplication.NIFSinJapanhasrecentlydevelopedan80kgheatV4Cr4Tialloy(NIFS-heat2)aftertheproductionofa500kgscaleV4Cr4TiinU.S.severalyearsago.PropertyevaluationofthealloyhasbeenputintoaninternationalcollaborationprogramunderthecoordinationofIEA(InternationalEnergyAgency).SWIPhasjoinedthecollabrationonthehydrogenembrittlementresistanceevaluationofthealloyt.

  • 标签: 钒合金 氢脆变 阻抗 NIFS
  • 简介:让x:Mn是有非零主管弯曲的脐的免费hypersurface。然后,x与Laguerre公制的g被联系,Laguerre张肌\mathbbL\mathbb{L},Laguerre形式C,和一个Laguerre秒基础形成\mathbbB\mathbb{B}它是在Laguerre下面的x的invariants转变组。如果它的Laguerre形式消失,hypersurfacex被称为Laguerreisoparametric并且\mathbbB\mathbb的特征值{B}是不变的。在这份报纸,我们在4分类所有Laguerreisoparametrichypersurfaces。

  • 标签: 自由曲面 第二基本形式 等参超曲面 主曲率 变换群 等参数
  • 简介:ThedevelopmentoftheGEANT4applicationforALICEsimulationwithinthealiRootframeworkisdescribed.TheG3toG4approachadoptedbyALICEcollaborationisexplained.Theoverviewofthedesign,presentimplementationandfunctionalityispresentedandtheremainingproblemsarediscussed.

  • 标签: ALICE实验 软件开发 GEANT4