简介：SodiumdithioniteinitiatedsulfinatodehalogenationofBrCF2CF2Risstudied.

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．

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简介：Bothenantiomersoffluoxetineweresynthesizedinfivestepsfromethylbenzoylacetate(1)usingmicrobial-chemicalapproachwithoverallyieldsof59%and62%respectively.(S)-Enan-tiomercanbeobtainedin>99%e.e.byrestingcellofbaker’syeastandtheRformwasproducedin81%e.e.byimmobilizedGeotrichumsp.G38.

简介：Quasiclassicaltrajectorycalculation(QCT)isusedfrequentlyforstudyingcollisionalenergytransferbetweenhighlyvibrationallyexcitedmoleculesandbathgases.Inthispaper,theQCToftheenergytransferbetweenhighlyvibrationallyexcitedC6F6andN2,O2andgroundstateC6F6wereperformed.TheresultsindicatethathighlyvibrationallyexcitedC6F6transferredvibrationalenergytovibrationaldistributionofN2,O2andgroundstateC6F6,sotheyareV-Venergytransfer.EspeciallyitismainlyV-VresonanceenergytransferbetweenexcitedC6F6andgroundstateC6F6,excitedC6F6transfersmorevibrationalenergytogroundstateC6F6thantoN2andO2.ThevaluesofQCT,-〈△Evib〉ofexcitedC6F6aresmallerthanthoseofexperiments.

简介：AseriesofdoubleperovskitesRSrMnFeO_6(R=La,Pr,Nd,Sm)wassynthesizedundermildhydrothermalconditions.Crystalgrowthsofthesamplesweresensitivetoalkalinity,temperature,fillingfraction,andcompositionofinitialreactionmixture.ThedesiredseriesofcompoundsbelongstotheclassofAA'BB'O_6perovskiteswitharandomdistributionofMnandFeatomsovertheB-cationsub-lattice.TheirstructuresshowthedistortedorthorhombicsymmetrywithspacegroupPnma.TheshapesandsizesofthecrystalswereanalyzedonaRigakuJSM-6700Fbyscanningelectronmicroscopy.AnalysisdonebyXPS,MssbauerspectroscopyandiodometrictitrationrevealsthatMnandFeionshave+4and+3oxidationstates,respectively.

简介：Bothenantiomersofdenopamineweresynthesizedusingmicrobial-chemicalapproachviabioreductionof1-(acetoxyphenyl)ketone4(R=CH2C1)and5(R=CO2Et)withfungusGeotrichumsp.G38.

简介：ＯｘｉｄａｔｉｖｅＤｅｈｙｄｒｏｇｅｎａｔｉｏｎｏｆＩｓｏｂｕｔａｎｅｔｏＩｓｏｂｕｔｙｌｅｎｅｏｖｅｒＦ￣－ＭｏｄｉｆｉｅｄＲａｒｅＥａｒｔｈＭｅｔａｌＯｘｉｄｅＣａｔａｌｙｓｔｓＺＨＡＮＧＷｅｉ－ｄｅ，ＴＡＮＧＤｉｎｇ－ｌｉａｎｇ，ＬＡＩＷｅｎ－...

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．

简介：(-)-(5R,6S)-6-Acetoxyhexadecan-5-olide1,anaturalmosquitoattractantpheromone,wassynthesizedfromreadilyavailablealdehyde2andcyclopentanone3usingL-proline-catalyzedasymmetricaldolreactionasthekeystep.

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.

简介：Thepaperdealswiththeinfluenceofanodematerialontheefficiencyofdegradationfororganicpollutantsinwatersystem.Theelectrochemicalperformanceoffluorineiondopedleaddioxide(F--PbO2)electrodeforthedegradationofanilinewascomparedwiththatofundopedleaddioxide(PbO2)electrodebyultraviolet-visible(UV-Vis)spectroscopy,linearvoltammetryandotheranalyticalmethods,suchasthemeasurementbychemicaloxygendemandanalyzer,highperformanceliquidchromatographyandscanningelectronmicrography.ItwasshownthatbothPbO2electrodeandF--PbO2electrodecouldmakeanilinebemineralizedcompletelyandhavethesamedegradationcourse,butF--PbO2electrodehasmuchhigherelectrocatalyticactivitythanundopedPbO2electrodefortheelectrochemicaldegradationofaniline.TheexperimentalresultsconfirmthatF--PbO2electrodehasmuchhigherpotentialforoxygenevolutionthanundopedPbO2electrode.

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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.

简介：在MP2/6-311＋＋G＊＊水平上优化乙烯酮自由基与LiX（X=F,Cl,Br）形成锂键复合物.当卤素的电负性很强（如F元素）,使得Li原子处于缺电子状态,此时,电子给体会把电子偏移向锂,形成共价性较强的锂键.而当卤素的电负性减弱时,锂键中主要成分逐渐变为离子键,并且此时锂键性质还要受电子给体影响.另外,由于HCCO为缺电子结构,电负性较弱且体积较大的卤素中的孤对电子会与HCCO之间通过静电相互作用,使得HCCO…Li—X键夹角变小,接近120°.锂键性质对HCCO…LiX（X=F,Cl,Br）复合物中Li—X的伸缩振动频率有直接影响.当锂键表现为共价性时,该频率红移,而当锂键表现为离子性时,该频率蓝移.但是,由于Cl的电负性与O的接近,C的电负性与Br接近所以,在O…Li…Cl和C…Li…Br中容易形成共振结构,导致远大于在其他复合物中的红移.

简介：Startedfrom5-hydroxy-2-pentanone,(R)(E)-3,7-dimethyl-2-octene-1,8-dioicacid,callosobruchusicacid,wassynthesizedviafivestepswithD-(-)-camphorsultamasthechiralauxiliary.Itwasofgoodopticalpurityandyield.

简介：（R）－N－乙酰四氢噻唑－2－硫酮－4－羧酸在三乙胺存在下同乙酰氯反应得到光学活性产物（R）－N－乙酰四氢噻唑－2－硫酮－4－羧酸．用半经验的量子化学方法研究反应物及产物的电子结构和反应热焓．

简介：采用半经验PM3方法对1,2,4-苯并噻二嗪-1,1-二氧类化合物的4种衍生物进行了量子化学计算,从几何构型、电子结构、前线分子轨道等几方面探讨了取代后体系电子性质的规律性变化,为药物合成提供理论基础和实验指导.

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简介：Anovelsupportedliquidphasefilmcatalyst:SupportedPdCl2-(n-C4H9)4N+Cl-moltensaltswasfoundtobeaneffectivecatalystwithgoodstabilityforselectivehydrodechlorinationofCCl2F2(CFC-12)toitsalternativesCH2F2andCHClF2.AdditionofCoCl2,GaCl3andCuCl2toPdCl2-(n-C4H9)4N+Cl-modifiesthecatalyticperformanceofsupportedmoltensalts.