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202 个结果
  • 简介:NineteenL-N-2-hydroxyethylaminoacidsandL-N,N-bis(2-hydroxyethyl)aminoacidswerepreparedfromthereactionofchlorohydrinwithL-alanine,L-valine,L-leucine,L-isoleucine,L-phenylalanine,L-serine,L-thrcunine,L-glutamicacid,L-asparticacidandglycine.L-N,N,N’,N’-tetra(2-hydroxyethyl)cystinewaspreparedbythereactionofL-cystinewithchlorohydrin.

  • 标签: hydroxyethyl PHENYLALANINE LEUCINE GLYCINE tetra solubility
  • 简介:采用噻吩-2-甲醛分别与邻氨基苯硫酚和硫代氨基脲合成了2种噻吩-2-甲醛杂环席夫碱.利用红外光谱、紫外-可见光谱、荧光光谱、X-射线单晶衍射分析、热重分析和核磁共振氢谱等检测方法对2种目标新型杂环类席夫碱产物的结构和性质进行了表征与分析.采用量子化学中常用的密度泛函方法(DFT)对2种新席夫碱化合物进行几何优化,采用单激发组态相互作用(CIS)和含时密度泛函方法(TD-DFT)进一步优化,比较计算光谱与实际测试光谱之间的误差,探究了2种席夫碱化合物荧光发光机制,为这类席夫碱分子结构设计提供了理论依据.

  • 标签: 杂环席夫碱 噻吩-2-甲醛 密度泛函理论
  • 简介:基于乙醇/水溶液体系结晶纯化制备了Fmoc-L-亮氨酸.通过HRMS,IR和1HNMR对该化合物进行了化学结构分析.被测化合物相对分子质量与Fmoc-L-亮氨酸理论相对分子质量一致,含有芴环、酰胺键和苯环等Fmoc-L-亮氨酸特征基团,其结构与目标化合物的分子结构一致.

  • 标签: 乙醇 水体系溶液 Fmoc-L-亮氨酸 化合物 化学结构 分析
  • 简介:InthispaperL^p-L^qestimatesforthesolutionu(x,t)tothefollowingperturbedhigh-erorderhyperbolicequationareconsidered,(ρπ--a△)(ρπ--b△)u+V(x)u=O,x∈R^n,n≥6,ρ1eu(x,O)=O,ρ^3eu(x,O)=f(x),(j=O,1,2).WeassumethattheotentialV(x)andtheinitialdataf(x)arecompactlysupported,andV(x)issufficientlysmall,thenthesolutionu(x,t)oftheaboveproblemsatisfiesthesameL^p-L^qestimatesasthatoftheunperturbedproblem.

  • 标签: L^p-L^q估计 高阶分支 双曲型偏微分方程 紧支撑
  • 简介:<正>InthispaperitisprovedthatforallcompletelydistributivelatticesL.thecategoryofL-fuzzifyingtopologicalspacescanbewmbeddedinthecategoryofL-topologicalspaces(stratifiedChang-Goguenspaces)asasimultaneouslybireflectiveandbicoreflectivefullsubcategory.

  • 标签: L-topological SPACE L-fuzzifying TOPOLOGICAL SPACE TOPOLOGICAL
  • 简介:WeconstructaclassofintegrablegeneralizationofTodamechanicswithlong-rangeinteractions.ThesesystemsareassociatedwiththeloopalgebrasL(Cr)andL(Dr)inthesensethattheirLaxmatricescanberealizedintermsofthec=0representationsoftheaffineLiealgebrasCr(1)andDr(1)andtheinteractionspatterninvolvedbearsthetypicalcharactersofthecorrespondingrootsystems.WepresenttheequationsofmotionandtheHamiltonianstructure.Thesegeneralizedsystemscanbeidentifiedunambiguouslybyspecifyingtheunderlyingloopalgebratogetherwithanorderedpairofintegers(n,m).Itturnsoutthatdifferentsystemsassociatedwiththesameunderlyingloopalgebrabutwithdifferentpairsofintegers(n1,m1)and(n2,m2)withn2<n1andm2<m1canberelatedbyanestedHamiltonianreductionprocedure.Forallnontrivialgeneralizations,theextracoordinatesbesidesthestandardTodavariablesarePoissonnon-commute,andwheneithernorm≥3,thePoissonstructurefortheextracoordinatevariablesbecomessomeLiealgebra(i.e.theextravariablesappearlinearlyontheright-handsideofthePoissonbrackets).Inthequantumcase,suchgeneralizationswillbecomesystemswithnoncommutativevariableswithoutspoilingtheintegrability.

  • 标签: 广义Toda力学 多体系统 泊松括号 非线性偏微分方程
  • 简介:Weconsiderforafixedμ,theclassofpolynomialsPn,μ,s:=P(z)=zsanzn-s+n-s∑j=μan-jzn-j-s;1≤μ≤n-sofdegreen,havingallzerosin|z|≤k,k≤1,withs-foldzerosattheorigin.Inthispaper,wehaveobtainedinequalitiesinthereversedirectionfortheaboveclassofpolynomials.Besides,extensionsofsomeTuran-typeinequalitiesforthepolarderivativeofpolynomialshavebeenconsidered.

  • 标签: 空间 多项式 NS NJS 不等式 原点
  • 简介:AnefficientroutetoprepareL-glucoseandL-galactoseisdescribed.TheL-sugarsareachievedbyusingthestrategyofswitchingthefunctionalgroupsatC1andC5ofD-glucoseandD-mannose.TheoxidationandreductionofthesilylenoletheratC1andthelead(IV)tetraacetatemediatedoxidativedecarboxylationatC5arethekeysteps.L-GlucoseandL-galactosearepreparedinaconvenientandinexpensiveway.

  • 标签: 半乳糖衍生物 D-葡萄糖 左旋 合成 D-甘露糖 甲硅烷基
  • 简介:Lp-LqdecayestimateofsolutiontoCauchyproblemofalinearthermoviscoelasticsystemisstudied.Byusingadiagonalizationargumentoffrequencyanalysis,thecoupledsystemwillbedecoupledmicrologically.Thenwiththehelpoftheinformationofcharacteristicrootsforthecoefficientmatrixofthesystem,Lp-LqdecayestimateofparabolictypeofsolutiontotheCauchyproblemisobtained.

  • 标签: 系统问题 柯西问题 衰变估计 CAUCHY问题 衰减估计 频率分析
  • 简介:1.IntroductionInthispaperweconsiderCauchyproblemforaclassofnonhomogeneousNavier-Stokesequationsintheinfinitecylinderwith.Givensatisfyinginthedistributionsensediv,weseekasolutionvectorandapressurefunctionP(t,x)suchthatwhereisanonlinearvector-valuedfun...

  • 标签: ADMISSIBLE triple NAVIER-STOKES equations CAUCHY problem
  • 简介:Inthispaper,asimplebutinherentrelationbetweentheL-integralandtheBueeknerworkconjugateintegralisprovedforcrackproblemsinisotropic,anisotropic,anddissimilarmateri-als,respectively.Itisfoundthat,intheabove-mentionedthreecases,theL-integral,fromthemath-ematicalpointofviewaswellasinprinciple,arisesfromBetti’sreciprocaltheorem.ThismeansthattheBuecknerworkconjugateintegralisamoregeneralpath-independentintegralthantheotherssinceanyotherpath-independentintegralscouldbederivedbyusin8theBuecknerintegralwhilechoosingadifferentsubsidiarystress-displacementfield.

  • 标签: INTEGRAL work CONJUGATE INTEGRAL crack SUBSIDIARY
  • 简介:We’llstudytheFEMforamodelforcompressiblemiscibledisplacementinporousmediawhichincludesmoleculardiffusionandmechanicaldispersioninone-dimensionalspace.Aclassofvertices-edges-elementsinterpolationoperatorinkisintroduced.Withthehelpofink(notellipticprojection),theoptimalerrorestimateinL∞(J;L2(Ω))normofFEMisproved.

  • 标签: Molecular diffusion and mechanical dispersion SINGLE-PHASE
  • 简介:Inthispaper,theLp-convergenceofGrünwaldinterpolationGn(f,x)basedonthezerosofJacobipolynomialsJ(α,β)n(x)(-1<α,β<1)isconsidered.Lp-convergence(00)ofGn(f,x)isobtainedfor-1<α,β≤0.Therefore,theresultsof[1]and[3-5]areimproved.

  • 标签: INTERPOLATION JACOBI ON L_p inequality notes