简介：The2-C,methylenegroupof1-aroyl-1,2-dihydro-3H-naphtho[2,1-b]pyran-3-ones(2)havebeenshowedtopossessasuperiorreactivitytowardsmanyoforganicreagents.Thena-phthopyrones(2)condensedwitharomaticaldehydestogivethe2-arylidinederivatives(3).Bromin-ationof2gave1,2-dibromo(4)or5-bromo(5)derivativesdependingonthereactionconditions.Thebasecatalyzedadditionorcycloadditionofnaphthopyrones(2)to4-methoxybenzalacetophenonegavetheexpectedMichaeladduct(6)orthecyclicadducts(7-9)dependingonthetypeofcatalyticbaseandreactionconditions.Structuresoftheproductshavebeenestablishedbyelementalanalyses,IRand~1HNMRspectroscopicmethods.
简介：Yb3+complexeswithtwonitrilotriaceticacidmoleculeswerepreparedandtheircompositionsweredeterminedasK3[Yb(nta)2(H2O)]*5H2OandNa3[Yb(nta)2]*6H2Obyelementalanalyses.Theirstructureswerecharacterizedbysingle-crystalX-raydiffractionanalyses.IncomplexK3[Yb(nta)2(H2O)]*5H2O,theYbN2O7partformsanine-coordinatemonocappedsquareantiprismaticstructure.IncomplexNa3[Yb(nta)2]*6H2O,theYbN2O6partformsaneight-coordinatesquareantiprismaticstructure.Itcanbeseenthattheoutercations(K+andNa+)greatlyaffectthecoordinationnumberandcoordinatestructurefromtheseresults.
简介：运用多种方法、多种基组对PF（X3∑-）的平衡结构进行优化计算．用QCISD／6—311G（df）方法得到的平衡结构为RPF=0．1589nm，与实验值RPF=0．15897nm进行比较，最为接近，得出QCISD／6—311G（d，）基组为最优基组；然后对PF（X3∑-）进行单点能扫描计算，用正规方程组拟合Murrell-Sorbie函数，得到相应电子态的势能函数解析式，由势能函数计算了与PF（X3∑-）态相对应的光谱常数，结果与实验数据较为一致．这些数据为反应动力学提供了理论依据．
简介：1,2-rearrangementsofcarbenes:CCH2X（X=CH2,NHandO）arestudiedbyusingabinitiogradientmethod.HeteroatomsNandOstabilizethecarbeneanddecreaseitsreactivity,mainlybychangingfrontiermolecularorbitals,butretainthewayofthereaction.ThereactionstartsfromtheattackofthemigratinghydrogenonthecarbenepAOandendswiththeentranceofthehydrogenintothecarbeneσorbital.ReactivitiesareintheorderofX=CH2>NH>O.Thereactionisexothermicorendothermicaccordingtowhethertheproductisa4n+2or4nπelectronmolecule.
简介：在水的答案的Co3+水和上的详细理论调查借助于模拟基于原子契约electronegativity均等方法熔化了进分子的力学(ABEEM/MM)的分子的动力学(MD)被执行了。有效Co3+离子水潜力被为离子的簇适合到abinitio结构和有约束力的精力构造了。然后离子水相互作用潜力与ABEEM-7P水模型一起在联合被用于单个Co3+(aq)答案的分子的动力学模拟，设法复制答案的许多试验性的结构、动态的性质。这里，不是仅仅共有的财产(光线的分发功能，尖分发功能和solvation精力)获得了因为在ABEEM-7P水答案的Co3+在对从试验性的方法和另外的分子的动力学模拟而且费用分布的很有趣的性质的那些的好同意，水分子的几何学，氢债券，散开系数，震动的系列被ABEEM/MM调查模型。
简介：ＨＥＡＴＳ ＯＦ ＩＮＴＥＲＡＣＴＩＯＮ ＯＦ ＯＲＧＡＮＩＣ ＢＡＳＥＳ ＷＩＴＨ ＰＯＬＹＭＥＲ ＰＲＯＴＥＣＴＥＤ ＣＡＴＡＬＹＳＴ ＰＶＣ－ＡｌＣｌ＿３ＨＥＡＴＳＯＦＩＮＴＥＲＡＣＴＩＯＮＯＦＯＲＧＡＮＩＣＢＡＳＥＳＷＩＴＨＰＯＬＹＭＥＲＰＲ...
简介：Fe2O3/activecarbon(Fe2O3/AC)nanocompositeswerereadilyfabricatedbypyrolyzingFe3+impregnatedactivecarboninanitrogenatmosphere.Theas-preparedcompositeswerestudiedbyX-raypowderdiffraction(XRD),X-rayphotoelectronspectroscopy(XPS)andtransmissionelectronmicroscopy(TEM).Thecapacitivepropertyofthecompositeswasinvestigatedbycyclicvoltammetry(CV)andgalvanostaticcharge-dischargetest.Physicalcharacterizationsshowthattheγ-Fe2O3finegrainsdispersedintheACwell,withameansizeof21.24nm.Electrochemicaltestsin6mol/LKOHsolutionsindicatethattheas-preparednanocompositesexhibitedimprovedcapacitiveproperties.Thespecificcapacitance(SC)ofFe2O3/ACnanocompositeswasupto188.4F/gthatwasderivedfrombothelectrochemicaldouble-layercapacitanceandpseudo-capacitance,whichwas78%largerthanthatofpristineAC.AsymmetriccapacitorwithFe2O3/ACnanocompositesaselectrodeshowedanexcellentcyclingstability.TheSCwasonlyreducedbyafactorof9.2%after2000cyclesatacurrentdensityof1A/g.
简介：
简介：Poly-3-methylthiophene(P3MT)在房间温度被综合离子的液体1-butyl-3-methylimi-dazoliumhexafluorophosphate([BMIM]PF6)由经常的潜在、经常的电流分别地。P3MT电影的结构和形态学被FTIR光谱和SEM描绘。undoped(减小)并且做(氧化)在离子的液体准备的P3MT电影的形式可逆、稳定。P3MT电影有维生素酸和罐头的electrocatalytic氧化的强壮的特征分开维生素酸和多巴胺的氧化山峰。潜在的步的二个方法被用来观察这部电影的反应时间，这部电影被发现有完美的electrochromic反应。
简介：NewrareearthvanadatesYSrQ-xCaxV3O9-y（x=0.0,0.67,1.0,1.33and2.0）havebeensynthesizedbyanewsimplemethod.X-raypowderdiffractionresultsshowthattheyaremono-phase.Theybelongtoorthorhombicstructureandtheirlatticeconstantsarecalculated.TheresultsofweightgainsinTGcurvesshowthatthelowervalentvanadiumisoxidizedtohighervalentstateathighertemperature.Theoxygencontentsofnewcompoundsarecalculatedfromtheweightgains.BothV3+andV4+coexistinYSr2-xCaxV3O9-y.Thesecompoundsexhibitlowelectricresistivityatroomtemperature.
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