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500 个结果
  • 简介:TheNb-bromomethylderivative(2)ofgelsemine,aquaternaryammoniumsalt,wasfoundtoberecalcitranttowardHofmanntypealkalinedegradationwhichhasbeensuccessfulinothercases.Instead,are-distributionoftheN-methylgrouptookplace,givingriseto3a,1,3band3c,indescendingorderofRfvalues.

  • 标签: DESCENDING hasbeen GIVING ALKALINE derivative toward
  • 简介:WestudythestructureofBernstein’sfirstsummableoperatorsandshowthattheycon-vergeuniformlytocontinuonsfunctionsonthespecialrealorthogonalgroupSO(n)inthispaper.Inaddition,wehavealsodiscussedtheapproximationdegreetoaclassoffunctionLipα(0<α≤1)onSO(n).

  • 标签: OPERATORS verge FIRST REAL UNIFORMLY kernel
  • 简介:TwospeciesofN-arylpyrazolescontainingactiveaminogroupweresynthesized.AndformylationsofN-arylpyazolescontainingaminoindifferentpositionofpyrazoleringsusingVilsmeier-Haackreactiongaveaseriesofusefulpyrazoleintermediates.Theimportantfeaturesofthisprotocolwerecheapmaterials,easyprocess,mildreactionconditionsandgoodyieldofproducts.

  • 标签: Vilsmeier-Haack反应 N-芳基吡唑 甲酰化 氨基 合成
  • 简介:Assumethateachcompletelyirrationalnoncommutativetorusisrealizedasaninductivelimitofcirclealgebras,andthatforacompletelyirrationalnoncommutativetorusAwofrankmthereareacompletelyirrationalnoncommutativetorusAρofrankmandapositiveintegerdsuchthattr(Aw)=1/d.tr(Aρ).ItisprovedthatthesetofallC^*-algebrasofsectionsoflocallytrivialC^*-algebrabundlesoverS^2withfibresAωhasagroupsturcture,denotedbyπ1^s(Aut(Aω)),whichisisomorphictoZifEd>1and{0}ifd>1.LetBcdbeacd-homogeneousC^*-algebraoverS^2×T^2ofwhichnonon-trivialmatrixalgebracanbefactoredout.ThesphericalnoncommutativetorusSρ^cdisdefinedbytwistingC^*(T2×Z^m-2)inBcd×C^*(Z^m-3)byatotallyskewmultiplierρonT^2×Z^m-2。ItisshownthatSρ^cd×Mρ∞isisomorphictoC(S^2)×C^*(T^2×Z^m-2,ρ)×Mcd(C)×Mρ∞ifandonlyifthesetofprimefactorsofcdisasubsetofthesetofprimefactorsofp.

  • 标签: 基本群 自同构群 非交换环 C^ *代数 向量积
  • 简介:ThispapercontinuestheworkofD.MacHale,D.Flannery(Proc.R.Ir.Acad.81A,209—215;83A,189—196)andtheauthor(Proc.R.Ir.Acad,90A,57—62;J.SouthwestChinaNormalUniversity15,No.1,21.—28)onthetopicon“FinitegroupswithgivenAutomorphismgroup”.Thefollowingresultisproved:LetGbeafinitegroupwithAutGaSchmidtgroup.ThenGisisomorphictoS3orKlain4-group.,orDsuchthatAutD=InnD.DisaSchmidtgroupoforder2?p.S2(∈Syl2D)isanormalandspecialgroupexoeptasupersperspecialgroupwithoutcommutativegenerators.

  • 标签: ISOMORPHIC COMMUTATIVE NILPOTENT SUBGROUP exponent maximal
  • 简介:TheHuayuGroupiscomposedofonecoreenterprise,nineclosely-relatedenterprisesand16loosely-relatedenterprisesinAnhui,JiangsuandZhejiang.Itsbusinessincludesfinance,materials,knitwear,garmentsandeducation.AnhuiChuzhouHuayu(Group)Co.Ltd.—acoreenterpriseofHuayuGroup—isacomprehensiveenterprisegroup,integratingproduction,trade,scientificresearchanddevelopment.Ithasastaffof4,000,andeightfactoriesandfivecompaniesunderitsadministration.Majorproductsincludesixseriesyarn

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  • 简介:“摩机”一词来源于英文“Modify”,是指针对音频产品的某些薄弱环节和设计缺陷加以改进,以较小的投资获得更高的性能。懂行的用户只需以较小的代价通过更换一些高性能元器件或简单改进一些设计,就能明显提高产品性能。因此,对于消费者来说摩机不失为一条获取高性价比的捷径。

  • 标签: 摩机 三诺 中频 产品性能 设计缺陷 音频产品
  • 简介:2006年初秋,三诺又向市场推出了一款旗下永恒系列的新品:N-35G。N-35G应用了全新的电子分频技术与全新的功放芯片,但售价却仅为488元,而N-35G也可以说是国内第一款中档价位而应用到电子分频技术的音箱产品。

  • 标签: 电子分频技术 三诺 书架箱 上市 功放芯片 应用
  • 简介:Itisprovedthatthereisnochaoticgroupactionsonanytopologicalspacewithfreearc.InthispaperthechaoticactionsofthegrouplikeG×F,whereFisafinitegroup,arestudied.Inparticular,underasuitableassumption,ifFisacyclicgroup,thenthetopologicalspacewhichadmitsachaoticactionofZ×Fmustadmitachatotichomeomorphism.Atopologicalspacewhichadmitsachaoticgroupactionbutadmitsnochaotichorneomorphismisconstructed.

  • 标签: 混沌群作用 拓扑空间 自由弧 有限群 循环群 混沌同胚