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199 个结果
  • 简介:这篇论文为答案在片是其弱熵的严格地凸的能量守恒定律涉及一个起始的边界价值问题明智的光滑的答案班由组成有限地许多断绝。由相应起始的价值问题和边界熵的弱熵答案的结构,状况开发了byBardos-Leroux-Nedelec,我们把一个构造方法给起始的边界价值问题的弱熵答案。与起始的值问题相比,起始的边界值问题的弱熵解决方案包括下列新相互作用类型:一个扩大波浪与边界碰撞,边界反映是到边界的正切的一个新冲击波。根据结构和弱熵答案的一些全球估计,我们导出全球L~1错误估计为粘滞到由使用匹配旅行的这个起始的边界价值问题的方法挥动答案方法。如果在里面胶粘的答案包括一个扩大波浪与边界碰撞,边界思考的相互作用是到边界的正切的一个新冲击波,或在里面胶粘的答案包括是到边界的正切的一些冲击波,然后的粘性答案的错误在里面胶粘的答案被O(ε~(1/2))在L~1标准围住;否则,处于起始的价值问题,L~1错误界限是O(ε|nε|)。

  • 标签: 标量守恒定律 初始边值 误差估计 粘性法
  • 简介:一新(2+1)维的格子方程被介绍在联合Toda格子和相对论的Toda格子(TL-RTL)的层次在开始的二个成员之上基于方程在(1+1)尺寸。为联合TL-RTLequations的层次的Darboux转变被构造。在联合TL-RTLequations的层次的开始的二个成员的答案,以及新(2+1)维的格子方程被theDarboux明确地获得转变。

  • 标签: 组合TL-RTL方程 可积系统 Darboux转化 Toda晶格方程
  • 简介:Antibacterialpoly(D,L-lactide)(PDLLA)fibrousmembranesweredevelopedviaelectrospinning,followedbysurfacemodificationwhichinvolvedplasmapretreatment,UV-inducedgraftcopolymerizationof4-vinylpyridine(4VP)andquaternizationofthegraftedpyridinegroupswithhexylbromide.ThesuccessofmodificationwithquatemizedpyridiniumgroupsonthePDLLAfibrousmembraneswasascertainedbyX-rayphotoelectronspectroscopy(XPS).TheantibacterialactivitiesofthesemembraneswereassessedagainstGram-positiveStaphylococcusaureus(S.aureus)andGram-negativeEscherichiacoli(E.coli).ThePDLLAfibrousmembranesmodifiedwithquaternizedpyridiniumgroupsshowedantibacterialefficiencyagainstbothbacteriaashighas99.999%.Theresultsdemonstratedthattheantibacterialactivitywasbasedontheinteractionofthepositivechargeofpyridiniumgroupandnegativelychargedcellmembraneofbacteria,resultinginlossofmembranepermeabilityandcellleakage.

  • 标签: 等离子体表面改性 聚乳酸纤维 吡啶季铵盐 抗菌活性 纤维膜 金黄色葡萄球菌
  • 简介:TheaimofthepresentpaperistoprovenewequivalenceresultsandL_p-staurationresultsonweightedsimultaneousapproximationbythemethodofBernstein-Durrmeyeroperators(includ-ingresultsin[7]).OneofthemaintoolsandcrucialestimatesmanagingtheconverseresultsisgivenbyadirectmodifiedVornorskajatheoremwhichusesthethirdorderweightedmodulusofsmoothness.

  • 标签: 改出 八一 镇山 人君
  • 简介:.Thesingle2dilationorthogonalwaveletmultipliersinonedimensionalcaseandsingleA-dilation(whereAisanyexpansivematrixwithintegerentriesand|detA|=2)waveletmultipliersinhighdimensionalcasewerecompletelycharacterizedbytheWutamConsortium(1998)andZ.Y.Li,etal.(2010).Butthereexistnomoreresultsonorthogonalmultivariatewaveletmatrixmultiplierscorrespondingintegerexpansivedilationmatrixwiththeabsolutevalueofdeterminantnot2inL2(R2).Inthispaper,wechoose2I2=(2002)asthedilationmatrixandconsiderthe2I2-dilationorthogonalmultivariatewaveletY={y1,y2,y3},(whichiscalledadyadicbivariatewavelet)multipliers.Wecallthe3×3matrix-valuedfunctionA(s)=[fi,j(s)]3×3,wherefi,jaremeasurablefunctions,adyadicbivariatematrixFourierwaveletmultiplieriftheinverseFouriertransformofA(s)(cy1(s),cy2(s),cy3(s))?=(bg1(s),bg2(s),bg3(s))?isadyadicbivariatewaveletwhenever(y1,y2,y3)isanydyadicbivariatewavelet.Wegivesomeconditionsfordyadicmatrixbivariatewaveletmultipliers.TheresultsextendedthatofZ.Y.LiandX.L.Shi(2011).Asanapplication,weconstructsomeusefuldyadicbivariatewaveletsbyusingdyadicFouriermatrixwaveletmultipliersandusethemtoimagedenoising.

  • 标签: Multi-wavelets FOURIER multipliers image denoising.
  • 简介:  Enantioimericallypure1,l'-bi-2-naphthol(BINOL)1anditsderivativesareimportantchiralligandsandauxiliariesforanumberofasymmetrictransformations1suchasaldolcondensations,alkylations,Diels-Alderreactions,Michaeladditions,epoxidations,etc.Opticallypure1andtheirderivativeshavealsobeenusedextensivelyinchiralrecognition,chiralseparationandintheconstructionoffunctionalisedmaterials2.Furthermore,(R)-and(S)-BINOLarealsofundamentalstartingmaterialsforthesynthesisofalargevarietyofotherchiralbinaphthylssuchasMOP(2c),NOBIN(2d)andBINAP(2e).Asaresultthedevelopmentofefficientandeconomicmethodsforthepreparationofopticallypure1hasattractedmuchattentioninrecentyears3andnovelmethodsfortheresolutionof(±)-1continuetobedeveloped.……

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  • 简介:TwoseriesofterritremBanalogues(10a-10cand18)havebeendesignedandsynthesizedfromjujubogenin5awhichwaspreparedfromjujubogeninglycosides5bobtainedfromtheleavesofZizyphusjujuba.Thestructuresofthenewcompoundswereconfirmedby1H-,13C-NMRandMSdata.Compounds10cand18showedweakinhibitoryeffectonAChEat10^-4mol/E.

  • 标签: 合成 2-内-l-安息香酸盐 TerritremB相似物 Jujubogenin 配糖基 药物提取
  • 简介:TheauthorsdiscussproblemsofapproximationtofunctionsinL^2(R^n)andoperatorsfromL^2(R^n1)toL^2(R^n2)byRadial-BasisFunctions.TheresultsobtainedsolvetheparblemofcapabilityofRBFneuralnetworks,abasicprobleminneuralnetworks.

  • 标签: 径向基函数 中性网络 逼近函数 算子
  • 简介:由di-(2,4,4-trimethylpentyl)的L本氨基丙酸的抽取行为phosphinic酸,di-(2,4,4-trimethylpentyl)-monothiophosphinic酸和di-(2-ethylhexyl)磷的酸分别地在二阶段、三阶段的系统被学习。为这些抽取反应的平衡常数是计算的。

  • 标签: EXTRACTION THREE-PHASE CYANEX272 Cyanex302 PHENYLALANINE
  • 简介:稀土元素aryloxides由各种各样的烷基组代替了[行(浆)3]例如甲基,isopropyl和tertbutyl,被用作单个部件催化剂影响L减水乳酸(LLA)的戒指洞聚合。催化活动,聚合特征,聚合动力学和机制被学习。稀土元素aryloxides的催化活动被结构和烷基组的数字在苯基戒指上影响,这被发现。越强壮烷基组的电子捐赠能力,催化活动将是越多higher。代用品组的数字的增加将导致一项更高催化的活动。镧tris(2,4,6-tri-tert-butylphenolate)[La(OTTBP)3]在所有镧aryloxides之中展出最高的活动。根据1H-NMR数据,LLA聚合经由包含减水乳酸的酰氧债券的劈开的协作插入机制继续了,这被建议。关键词戒指洞聚合-L减水乳酸-稀土元素aryloxides这个工作被山西省(号码2006011069)的自然科学基础和山西省(号码2009011059-7)的关键实验室的开的基础支持。

  • 标签: 聚合反应动力学 环烷基 稀土 开环 催化活性 乳酸
  • 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:GinsenosidesRg1,Re,Rb1,Rc,Rb2,Rb3,andRdindifferentpartsoftheAmericanginsengplantwereinvestigated.Theextractionprocesswasapressurizedmicrowave-assistedextraction(PMAE).Thesevenginsenosideswereseparatedanddeterminedbyhigh-performanceliquidchromatography(HPLC)withaultraviolet(UV)detector,at203nm.TheexperimentresultsshowedsignificantvariationsintheindividualginsenosidecontentsoftheAmericanginsengindifferentpartsandagesoftheplant.Theresultsdemonstratedthattheleaves,roothairs,andrhizomesofPanaxquinquefoliusL.containedhigherginsenosidecontents,followedbythemainrootsandstems.TheleavescontaineddramaticallyhigherlevelsofginsenosideRg1,Rb3,andRdthantheotherfourparts.HighercontentsofRb1andRewerepresentinthemainroots,roothairs,andrhizomes.Theamountofginsenosidecontentinthestemswasthelowest.Thetotalcontentofthesevenginsenosidesinmainroots,roothairsandrhizomesincreasedwiththeageoftheplant.Incontrast,theginsenosidecontentsintheleavesandstemsdecreasedwithayearofgrowth.

  • 标签: 美国人参 人参皂苷 高性能液体色谱法 化学分析
  • 简介:Arareearthcoordinationsystemwasfirstinvestigatedasanewtypeofcatalystforthering-openingpolymerizationofα-aminoacidN-carboxyanhydrides(NCAs).Theresultsforthepolymerizationofγ-stearyl-α,L-glutamate(SLG)NCAusingneodymiumacetylacetonate(Nd(acac)3)-orneodymiumtris(2-ethylhexylphosphonate)(Nd(P204)3)-triethylaluminum-waterascatalystswerecomparedwiththoseusingconventionalcatalysts.Itwasfoundthatthehelicalpoly(γ-stearyl-L-glutamate)withhighmolecularweightaswellasnarrowmolecularweightdistributioncanbeobtainedinthepresenceofNd(acac)3/AlEt3-1/2H2O.ThepolymerobtainedwascharacterizedbyIRandNMRspectroscopy.

  • 标签: Rare earth COORDINATION catalyst RING-OPENING POLYMERIZATION
  • 简介:Thestructureandkineticsofthecomplexformedbyhyaluronicacid(HA)andpoly(L-lysine)(PLL)werestudiedbytimeresolvedlaserlightscattering,TEM,andAFM.BecauseHAhasahydrophilicbackbone,thecomplexesformedbyHAandPLLaredifferentfromthoseformedbyoppositelychargedpolyelectrolytesbothhavinghydrophobicbackbones.Insteadofformingstrongaggregatesandevenprecipitates,thecomplexinthepresenceofexcessHAisstableinthestudiedtimeperiod.Moreimportantly,thecomplexspontaneouslyformscore-coronastructurebytherearrangementofHAchains.ThecoreiscomposedofcomplexrichofPLLandthecoronaismainlyHA.FurtheranalysisshowsthatthehydrogenbondformedbyHAcreatesabarrierhinderingthefurtherrelaxationofHAchains.Theautomaticformationofcore-coronastructurebyPLL/HAishelpfulnotonlytounderstandtherelaxationofpolyelectrolyteincomplex,butalsotodevelopdrugcarrierswithdesirableproperties.

  • 标签: POLYELECTROLYTE complex Core-corona STRUCTURE Hyaluronic acid
  • 简介:Anewcerebroside,1-O-(β-D-glucopyranosyloxy)-(2S,3R,4E,8Z)-2-[(2′R)-2’-hydroxylignoceranoylamino]-4,8-tetradecene-3-diolwasisolatedfromthe60%EtOHextractoftraditionalChinesemedicalplantCyperusrotundusL.Itsstructurewasdeterminedonthebasisofspectroscopicdata.Thisnewcompoundshowedanti-proliferationeffectonvascularsmoothmusclecells(VSMCs).

  • 标签: CYPERUS rotundus CEREBROSIDE ANTI-PROLIFERATION EFFECT Vascular
  • 简介:AnewgeneralizedJacobiellipticfunctionmethodisusedtoconstructtheexacttravellingwavesolutionsofnonlinearpartialdifferentialequations(PDEs)inaunifiedway.Themainideaofthismethodistotakefulladvantageoftheellipticequationwhichhasmorenewsolutions.Morenewdoublyperiodicandmultiplesolitonsolutionsareobtainedforthegeneralized(3+1)-dimensionalKronig-Penny(KP)equationwithvariablecoefficients.Thismethodcanbeappliedtootherequationswithvariablecoefficients.

  • 标签: 椭圆方程 孤立解 行波解 非线性偏微分方程 计算数学