简介:一系列新奇phthalimides对七phytopathogenic真菌在vitro为抗真菌的活动作好准备并且测试:Rhizoctoniasolani,镰刀霉oxysporumf.sp。cucumerinum欧文,Botrytiscinerea,Fulviafulva,SclerotiniasclerotiorumdeBary,Phytophthoracapsici,Botryosphaeriaberengeriama。结果证明保持6-methylpyridin-2-yl的结构的那些混合物对Phytophthoracapsici和Botrytiscinerea展出了好活动。
简介:AdynamicalLangevinmodelisemployedtoevaluatetheexcessoftheneutronemissioninthefissionofheavynuclei~(240)Cf,~(246)Cf,~(254)Cf,~(240)Urelativetothestandardstatistical-modelpredictionatvarioussaddle-to-scissionfrictionstrengths.Itisshownthatwhentheneutron-to-protonratioN/Zofthesystemincreases,thesensitivityoftheexcesstothefrictiondecreasessubstantially,anditalmostdisappearsfor~(240)U.WesuggestthatusingthosecompoundsystemswithlowN/Zfavorsanaccuratedeterminationforthesaddle-to-scissionfrictionstrengthbasedonthemeasurementofthepre-scissionneutronmultiplicity.
简介:SupposethatDisaboundeddomainwithapiecewiseC^1smoothboundaryinC^n.Letψ∈C^1+α(δD).ByusingtheHadamardprincipalvalueofthehigherordersingularintegralandsolidanglecoefficientmethodofpointsontheboundary,wegivethePlemeljformulaofthehigherordersingularintegralwiththeBoehner-Martinellikernel,whichhasintegraldensityψ.Moreover,bymeansofthePlemeljformulaandmethodsofcomplexpartialdifferentialequations,wediscussthecorrespondingCauehyboundaryvalueproblemwiththeBoehner-Martinellikernelonaclosedpiecewisesmoothmanifoldandobtainitsuniquebranchcomplexharmonicsolution.
简介:ThisworkstudiesTedopingeffectsonthedirectbandgapphotoluminescence(PL)ofindirectGaxIn1-xPalloys(0.72≤x≤0.74).Thetemperature-dependentPLshowsthattheenergydifferencebetweendirectΓvalleyandindirectXvalleysisreducedduetothebandgapnarrowing(BGN)effect,andthedirectbandtransitiongraduallydominatesthePLspectraastemperatureincreases.CarrierthermalizationhasbeenobservedforTe-dopedGaxIn1-xPsamples,asintegratedPLintensityincreaseswithincreasingtemperaturefrom175to300K.Theactivationenergyforcarrierthermalizationisreducedasdopingconcentrationincreases.BothBGNeffectandcarrierthermalizationcontributetothecarrierinjectionintotheΓvalley.Asaresult,thedirectbandtransitionisenhancedintheTe-dopedindirectGaxIn1-xPalloys.Therefore,thePLintensityoftheGa0.74In0.26Psamplewithactivedopingconcentrationof9×1017cm-3isincreasedbyfivetimescomparedwiththatofanominallyundopedsample.ItisalsofoundthatthePLintensityisdegradedsignificantlywhenthedopingconcentrationisincreasedto5×1018cm-3.Fromcross-sectiontransmissionelectronmicroscopy,nolargedopantclustersorotherextendeddefectswerefoundcontributingtothisdegradation.
简介:Sixnewopticallyactivepoly(amide-imide)s(5a-f)weresynthesizedthroughthedirectpolycondensationreactionofN,N'-(4,4'-diphthaloyl)-bis-L-leucine(3)withsixhydantoinderivatives(4a-f).Triphenylphosphite(TPP)/pyridineinthepresenceofcalciumchloride(CaCl_2)andN-methyl-2-pyrrolidone(NMP)weresuccessfullyappliedfordirectpolycondensation.Thepolycondensationreactionsproduceaseriesofnewpoly(amide-imide)s(5a-f)inhighyields,andinherentviscositybetween0.42and0.55dL/g.Theresultingpoly(amide-imide)s(5a-f)werecharacterizedbyelementalanalysis,viscositymeasurements,thermalgravimetricanalysis(TGAandDTG),solubilitytestandFT-IRspectroscopy.
简介:Anovelsupportedliquidphasefilmcatalyst:SupportedPdCl2-(n-C4H9)4N+Cl-moltensaltswasfoundtobeaneffectivecatalystwithgoodstabilityforselectivehydrodechlorinationofCCl2F2(CFC-12)toitsalternativesCH2F2andCHClF2.AdditionofCoCl2,GaCl3andCuCl2toPdCl2-(n-C4H9)4N+Cl-modifiesthecatalyticperformanceofsupportedmoltensalts.
简介:这篇论文建议通过为N车辆探索问题分析它的输入条件估计问题的计算复杂性的一个方法。N车辆问题第一被提出在1的排列的集合决定最佳的代替到N。这个问题的复杂性N(问题的输入规模)是因素的。到平衡精确性和一般算法的效率,这篇论文提及一个新系统的算法图案并且讨论在问题和它的输入条件的复杂性之间的通讯,除就象往常一样提出一个一致近似算法以外。这是为分析NP问题的计算的一种新技术。方法相应然后被介绍。我们最后执行模拟验证方法的优点:1)到在枚举的减少计算;2)高效地为任何N车辆盒子获得计算复杂性;3)由方法估计了根据它的复杂性为任何N车辆盒子指导一个算法图案。
简介:主要讨论了部分ToeplitzN-矩阵的完成问题及一类特殊结构的位置对称的部分N-矩阵的完成.
简介:在这个工作我们在场关于借助于在与形状保存有关的假设下面的一个线性操作符的一个函数的k-th衍生物的近似的结果性质。作为后果,我们关于Meyer-K推出新结果?nig和Zeller操作员。
简介:采用密度泛函理论的B3LYP方法、从头算的MP2方法和自洽反应场极化连续模型(PCM),在6-311++G(2d,2p)基组水平上研究了N,N’-二甲基-S-异苯并呋喃在气相和溶液中发生S→N烷基重排反应的机理、溶剂效应和取代基效应.结果表明:该反应通过四元环机理和双位迁移机理生成产物,在气相和溶剂水中,双位迁移途径的能垒均比四元环途径低,反应主要通过双位迁移途径生成产物.在气相,苯环上发生-Cl,-NO2和-OCH3取代时,双位迁移途径的能垒在MP2/6-311++G(2d,2p)水平上比没有取代时分别低4.18,7.61,4.96kJ/mol,反应的取代基效应不明显.而在溶剂水中,苯环上发生-Cl,-NO2和-OCH3取代时,双位迁移途径的能垒在PCM-MP2/6-311++G(2d,2p)水平上比气相时分别低37.73,39.96和37.17kJ/mol,反应的溶剂化效应非常明显.理论研究结果与实验观察结果一致.
简介:Animprovedmethodisdevelopedbyusingstronglyacidiccationexchangeresin(001×1,H^+form)asacatalystforthesynthesisofdiphenyl1-(N-benzyloxycarbonyl-amino)alkanephosphonatesand1-(N-benzyloxycarbonylamino)alkanephenylphosphinicacidsinhighyields.