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403 个结果
  • 简介:'ChemicalResearchinChineseUniversities',sponsoredbyJilinUniversitymandatedbytheMinistryofEducationofP.R.ChinaandpublishedbyHigherEducationPressinChina,isacomprehensiveacademicjournalinthefieldofchemistry.Thejournalcontainsoriginalpapers,researchnotes,lettersandreviewswrittenbyfaculty

  • 标签: 《高等学校化学研究》 作者 期刊编辑 学报发展
  • 简介:  ThemissionoftheChemicalProcessR&DDepartmentatDuPontPharmaceuticalsCompanyistosupplydrugsubstanceinatimelyfashionandtodiscover/developascalable,economical,environmentallyfriendlyprocessforthecommercialproductionofthebulkdrugsubstance.Severalexampleswillbepresentedtoillustrateourefforttoaccomplishthemission.Briefdiscussionwillincludethefollowingprojects:1)SynthesisofDMP728,acyclicpeptideofGPIIb/IIIainhibitor2)Methodforthepreparationofa-chloroboronicacid,akeyintermediateforDuP714,apotentthrombininhibitor3)ProcessresearchanddevelopmentofRoxifiban,apotentandorallyactiveGPIIb/Illainhibitor  ……

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  • 简介:利用密度泛函理论(Densityfunctionaltheory,DFT)在B3LYP/6-311++G(d,声)水平上研究了外电场(-15.43~15.43V/nm)对氟利昂F13(三氟氯甲烷,CRCl)分子物理和光谱特性的影响.计算结果表明,在C~Cl键连线z方向上,外电场从-15.43V/nm逐渐增加到15.43V/nm时,分子体系能量先增大后降低,偶极矩表现为先减小后增大,能隙ElG先增加后减小,C-Cl键键长逐渐增大,C-F键键长逐渐减小.外电场对CRCl分子红外振动光谱的频率和强度也有影响.进一步研究发现在外电场作用(O到15.43V/nm)逐渐增强下,CRCl分子的势能曲线束缚形态逐渐被解开,解离的势垒逐渐减小.在强度为15.43V/nm的电场作用下,CF3Cl分子将会发生C-C1键断裂而降解,该结果为对氟利昂进行外电场降解提供重要的参考依据.

  • 标签: 氟利昂 外电场 降解 光谱 DFT
  • 简介:根据Af-Ag自由基加聚反应的数量分布函数,导出凝胶点附近的渐进分布函数和高分子矩的表示式.进一步应用标度变换,得到了描述溶胶-凝胶相变的广义标度律,从而揭示了Af-Ag自由基加聚的固化反应是一个相变过程.

  • 标签: 标度律 自由基聚合 凝胶点 高分子矩
  • 简介:Theauthorsfocusedtheirattentionontheestablishmentofamesenchymalstemcell(MSC)modelforscreeningtraditionalChinesemedicines(TCMs)soastoinvestigatetheeffectsofShuanglongFormula(SLF)components(Ginsenosidesandsalvianolicacids)andingredients(ginsenosideRb1andsalvianolicacidB)oncardiomyocytedifferentiationfromMSCs.TheSLFcomponentswereanalyzedandquantifiedbyHPLC-TOF-MS.CardiomyocytedifferentiationwasinducedbyculturingMSCsintheinductionmediumsupplementedwithSLFingredients,SLFcomponents,5-azacytidine(5-aza),5-aza+SLFingredientsand5-aza+SLFcomponents,respectively,forupto30d,andevulatedbytheexpressionofCardiac-specificmyosinheavychain(MHC)andtroponinI(TnI)viaimmunofluoresentstaining.Slowgrowthrateandchangedmorphologywereobservedduringcardiomyocytedifferentiation.After20dofinduction,differentiatingMSCswerepositiveforMHCandTnIstaining.TheeffectsofSLFcomponentswerebetterthanthoseofSLFingredients.Takentogether,SLFcaninducethedifferentiationofMSCsintocardiomyogeniccellsinvitro,andMSCscanbeusedasapowerfultoolforscreeningTCMs.

  • 标签: 间质干细胞 模型筛选 中药 心肌细胞分化 诱导分化 肌钙蛋白I
  • 简介:毛状的电气泳动(CE)能分开收费并且有高速度和效率的中立物质。在这篇论文,利用meso-octamethylcalix[4]吡咯,meso-tetraspirocyclohexylcalix[4]是的吡咯,bimethyl双性人(2-pyrryl)甲烷和1,1双性人(2-pyrryl)环己烷在毛状的地区电气泳动(CZE)的添加剂电解质,他们无机的阴离子的识别能力被讨论。dipyrrylmethanes比其它有更好的识别能力。他们由CZE的七个正常无机的阴离子的分离上的效果被学习。

  • 标签: 无机化学 阴离子 吡咯 毛细管 电泳法
  • 简介:Quasiclassicaltrajectorycalculation(QCT)isusedfrequentlyforstudyingcollisionalenergytransferbetweenhighlyvibrationallyexcitedmoleculesandbathgases.Inthispaper,theQCToftheenergytransferbetweenhighlyvibrationallyexcitedC6F6andN2,O2andgroundstateC6F6wereperformed.TheresultsindicatethathighlyvibrationallyexcitedC6F6transferredvibrationalenergytovibrationaldistributionofN2,O2andgroundstateC6F6,sotheyareV-Venergytransfer.EspeciallyitismainlyV-VresonanceenergytransferbetweenexcitedC6F6andgroundstateC6F6,excitedC6F6transfersmorevibrationalenergytogroundstateC6F6thantoN2andO2.ThevaluesofQCT,-〈△Evib〉ofexcitedC6F6aresmallerthanthoseofexperiments.

  • 标签: 准经典轨道计算 碰撞能转换 C6F6 N2 O2 氟苯
  • 简介:OxidativeDehydrogenationofIsobutanetoIsobutyleneoverF ̄-ModifiedRareEarthMetalOxideCatalystsZHANGWei-de,TANGDing-liang,LAIWen-...

  • 标签: OXIDATIVE DEHYDROGENATION Isobutance RARE EARTH CATALYSTS
  • 简介:TofindoptimalconditionsforexpressingthesolubleformofsFv-2F3andtostudythepurificationandpropertyofitsderivativeSe-sFv-2F3,thepreferredexpressionconditionswereinvestigatedbymeansoforthogonaldesign.Thesecultureconditionsincludedincubationtemperature,inducerconcentration,inductiontimeandcellconcentration.TheevaluationofexpressionwasaccomplishedbytheanalysisofwholecelllysatesandtheyieldofsolublesFv-2F3wascalculatedaccordingtotheanalysisofProfinder(FTI-500,Pharmacia).Thepurificationprocedurewascarriedoutviaatwo-steppurificationprocedureconsistingofion-exchangechromatography,followedbyimmobilizedmetalaffinitychromatography(IMAC).TheantioxidantefficacyofSe-sFv-2F3wasdemonstratedbythedeterminationofthecontentofthemainproductoflipidperoxidation,MDA,theviabilityofcellsandtheactivityofLDH.WeobtainedthepreferredcultureconditionstogrowtheengineeredbacteriaandtheprocedureforpreparingsolublesFv-2F3andconfirmedtheantioxidantefficacyofSe-sFv-2F3.

  • 标签: Se-sFv-2F3 可溶表示 谷胱甘肽过氧化物酶 抗氧化剂
  • 简介:Thepaperdealswiththeinfluenceofanodematerialontheefficiencyofdegradationfororganicpollutantsinwatersystem.Theelectrochemicalperformanceoffluorineiondopedleaddioxide(F--PbO2)electrodeforthedegradationofanilinewascomparedwiththatofundopedleaddioxide(PbO2)electrodebyultraviolet-visible(UV-Vis)spectroscopy,linearvoltammetryandotheranalyticalmethods,suchasthemeasurementbychemicaloxygendemandanalyzer,highperformanceliquidchromatographyandscanningelectronmicrography.ItwasshownthatbothPbO2electrodeandF--PbO2electrodecouldmakeanilinebemineralizedcompletelyandhavethesamedegradationcourse,butF--PbO2electrodehasmuchhigherelectrocatalyticactivitythanundopedPbO2electrodefortheelectrochemicaldegradationofaniline.TheexperimentalresultsconfirmthatF--PbO2electrodehasmuchhigherpotentialforoxygenevolutionthanundopedPbO2electrode.

  • 标签: 二氧化铅阳极 电化学降解 电化学性能 掺杂 苯胺 PBO2电极
  • 简介:采用密度泛函B3LYP/6-311G(d,p)方法对CH3F与C2H3的反应体系进行了理论研究,获得了反应的势能面信息及可能的微观机理.在QCISD(T)/6-311++G(d,p)水平上精确计算了各反应物种的单点能.结果表明,除抽提氢反应外,标题反应还存在抽提氟(R1)、消氟化氢(R2)、消氢(R3)和自由基形成(R4)四类反应.在QCISD(T)/6-311++G(d,p)//B3LYP/6-311G(d,p)水平上,R1,R2,R3和R4反应的能垒分别是163.9,152.2,209.8和224.2kJ·mol-1,相应反应能为-56.6,-164.3,-2.7和-156.0kJ·mol-1,所有反应均放热,为热力学允许的反应.

  • 标签: CH3F C2H3 反应机理 过渡态 消氟化氢反应