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．

简介：Thenovelcomplex[K(18-C-6)]2[Cd(mnt)2][18-C-6-18-crown-6,nmt=1,2-dicyanoethene-1,2-dithiolate,C2S2-(CN)2^2-]wassynthesizedandcharacterizedbyelementalanalysis,IRspectrumandX-raydiffractionanalysis.Thecomplexdisplaystwo-dimensionalnetworkstructureof[K(18-C-6)]complexsegmentsand[Cd(nmt)2]complexsegmentbridgedbyS-K-S,S-K-NandN-K-Ninteractionsbetweenadjacent[K(18-C-6)]and[Cd(mnt)2]units.

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

简介：ToanalyzetheantitumorpotentialandmechanismofactionofsimultaneousNewcastlediseasevirus(NDV)hemagglutinin-neuraminidase(HN)andhumaninterleukin18(hIL-18)genetransferinC57BL/6micewithH22hepatoma,themousemodelwithH22hepatomawasestablishedinC57BL/6mice,andtheantitumoreffectsofthecombinedapplicationofNDVHNandhIL-18wereevaluatedinvivo.Theresultsshowthatthegrowthofestablishedtumorsinmiceimmunizedwithadenovirus(Ad)-HNinconjunctionwithAd-hIL-18wassignificantlyinhibitedcomparedwiththatinmiceimmunizedwithAd-HN,Ad-hIL-18alone,ortheemptyvector(Ad-mock).Furthermore,theimmunizationofmicewithAd-HNinconjunctionwithAd-hIL-18elicitedstrongnaturalkilleractivityandH22tumor-specificcytotoxicTlymphocyte(CTL)responsesinvivo.Inaddition,TcellsfromthelymphnodesofmiceimmunizedwithAd-hIL-18orAd-HN+Ad-hIL-18secretedhighlevelsoftheTh1cytokineIL-2andinterferon-γ(IFN-γ),indicatingthattheregressionoftumorcellsisrelatedtoaTh1-typedominantimmuneresponse.TheseresultsdemonstratethatvaccinationwithNDVHNtogetherwithhIL-18maybeanovelandpowerfulstrategyforcancerimmunotherapy.

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：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：Onenovelorganic-inorganichybridsupramolecularassemblies|（NDPA）（18-crown-6）]2+（DMA）+·3ClO4-（1）,hasbeensuccessfullyconstructedthroughtheprominentstrategiesofcrystalengineering（NDPA=N,N-dimethyI-1,4-phenylenediamine,DMA=dimethylamine）,andcharacterizedbyIR,powderXRDandsinglecrystalX-raydiffraction.Inthestructure,thesupramolecularorganiccationsandinorganicClO4-anionsarearrangedalternatelyandlinkedbyN-O…Hhydrogenbonds.ItisworthytonotethattheClO4-arelinkedtoformone-dimensionalinorganicchainthroughstrongNH…Ohydrogenbondsalongb-axis.Thereisnodistinctdielectricanomalyinthetemperaturedependentandfrequency-dependentdielectricconstantcurves,suggestingthatnophasetransitionexistswithinthemeasuredtemperaturerange（120-420K）.Therelativedisplacementofcationsandanions,theturnedpolarizationofmolecularelectricmomentandmacrocyclicmoleculerotatorarethemainfactorstodeterminethetrendofdielectricconstant.

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：采用微波消解样品，应用电感耦合等离子体质谱法（ICP-MS）同时测定正山小种红茶中Na、Mg、K、Ca、Fe、A1、Zn、Mn、Cu、Ge、Cd、Cr、Ni、Se、Mo、Hg、As和Pb18种元素。对于所测元素校准曲线的相关系数＞O．9990，回收率范围为90．1％-108．1％，相对标准偏差为1．54％-7．57％。正山小种红茶中Na、Mg、K、Ca、Fe、A1、Zn、Mn、Cu、Ge、Cd、Cr、Ni、Se、Mo、Hg、As和Pb18种元素可用ICP-MS法同时测定，方法简便、快速、准确，灵敏度高。

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

简介：提出了一种求解离子晶体等价格点的单粒子离子Dirac方程方法，确定离子晶体的点电荷电量。利用阴阳离子上分配的价电子数之比，给出了计算离子晶体化学键性质的关单式计算了MX（M=Li、Na、K、Rb、X=F、Cl、Br、I）系列晶体点电产电量值和化学键性质，得到了比较好的结果

简介：采用UMP2/6-311＋G（3df）方法研究了一系列化合物M_（n＋1）F_n（n=1,2;M=Na,K）体系的几何构型及非线性光学性质（NLO）.结果表明：这些体系均为超价化合物,均拥有较大的第一超极化率（β_0）.尤其是Na_3F_2体系中结构2c的β_0值为29.16×10~（-49）C~3·m~3·J~（-2）,是已知超价化合物Li_3F_2的2c结构的β_0值2.22×10~（-49）C~3·m~3·J~（-2）的13.1倍.

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简介：在常规条件下合成了一种新型的氨基酸功能化的多金属氧酸盐化合物[（Gly）2（H2O）2Cu]K3[Al（OH）6Mo6O18]·7H2O，并通过元素分析、红外光谱、紫外可见光谱、热重分析和X射线单晶衍射等方法对其晶体结构进行了表征．结构分析表明：该晶体属于三斜晶系，Pi空间群，晶胞参数a=0．81053（16）nm，b=1．1394（2）nm，c=1．8247（4）nm，α=93．96（3）°，β=92．89（3）°，γ=108．90（3）°，V=1．5858（5）nm^3，Z=2．