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  • 简介:ThispapershowsthattheC1-curvedfiniteelementdevelopedbyBernadoningeneralcannotsatisfytheessentialboundaryconditionsonapproximateboundary.Furthermore,amodifiedC1-curvedfiniteelementisgiven,whichiscompatiblewiththeelementofArgyristriangleandcansatisfythehomogeneousDirichletboundaryconditionsonapproximateboundary.

  • 标签: Curved boundary DOMAIN Argyris TRIANGLES C1-curved
  • 简介:C19-DITERPENOIDALKALOIDSOFDELPHINIUMMOLLIPILUM¥SuoMingZHANG;QingYuOu(LanzhouInstituteofChemicalPhysics,ChineseAcademyofSci?..

  • 标签:
  • 简介:Carbon-supportedPdnanoparticleswerepreparedbymicrowaveheating-glycolreductionmethod,andcharacterizedbyawidearrayofexperimentaltechniquesincludingX-raydiffractionspectroscopy(XRD)andtransmissionelectronmicroscopy(TEM).TheelectrooxidationbehaviorsofethanolonthePd/Celectrodeinalkalinemediawereinvestigatedusingcyclicvoltammetry(CV),chronoamperometry(CA),electrochemicalimpedancespectroscopy(EIS)andsinglecellperformancemethods.Pd/Celectrodeforethanoloxidationshowedhighelectro-catalyticactivityandlongtermstability.However,itisobservedthatthecurrentdensitydecreaseswiththeincreasingofthepotentialandnegativeimpedancepresentsinthepotentialfrom-0.1to0.1V.Thedecreasingcurrentdensityandthenegativeimpedancecouldbeduetotheadsorbedintermediatesspeciesthatinhibitedthefurtheroxidationofethanol.BasedonthechemicalreactionanalysisandEISspectra,equivalentcircuitsrelatingtovariouspotentialzoneshavebeenobtained.TheseresultsrevealthedynamicadsorptionofintermediatesspeciesonPdsurfaces.Significantly,itisclarifiedthattheadsorptionbehaviorbeginsfromthemaximumcatalysisofelectro-catalysisandendsintheformationofthepalladium(II)oxidelayerontheelectrodesurface.

  • 标签: 纳米颗粒 碱性介质 氧化钯 乙醇 X射线衍射谱 电化学阻抗谱
  • 简介:TheCprogramminglanguageisexpressiveandflexible,butnotsafe;asitsexpressivepowerandflexibilityareobtainedthroughunsafelanguagefeatures,andimproperuseofthesefeaturescanleadtoprogrambugswhosecausesarehardtoidentify.SinceCiswidelyused,anditisimpracticaltorewriteallexistingCprogramsinsafelanguages,sowaysmustbefoundtomakeCprogramssafe.ThispaperdealswiththeunsafefeaturesofCandpresentsasurveyonexistingsolutionstomakeCprogramssafe.Wehavestudiedbinary-levelinstrumentationtools,sourcecheckers,source-levelinstrumentationtoolsandsafedialectsofC,andpresentacomparisonofdifferentsolutions,summarizedthestrengthsandweaknessesofdifferentclassesofsolutions,andshowmeasuresthatcouldpossiblyimprovetheaccuracyoralleviatetheoverheadofexistingsolutions.

  • 标签: C语言 程序设计语言 信息安全 编译工具
  • 简介:ThispaperintroducestheconceptoflocalC-cosins-familyandinverstigateitsbasicproperties,Inparticular,acharacterizationofthecompleteinfinitesimalgeneratorofalocalC-cosinefamilyisobtained,AsanapplieationofthistheorytothesecondordersbstractCauchyproblems,acharacterizationofthelocalC-well-posednessoftheseproblemsisgivenintermsofthelocalC-cosinefamilytheory.

  • 标签: 余弦族 完全生成元 二阶柯西问题 半群
  • 简介:LetιbeatriangulationofapolygonaldomainDR2withverticesV={v1:1≤i≤N,}andRSk(D,τ)={u∈Ck(D):(T∈τ,u|τisarationalfunction}.Thepurposeofthispaperistostudytheexist-enceandconstructionofCμ-rationalsplinefunctionsonanytriangulationτforCAGD.TheHermiteprob-lemHμ(V,U)={findu∈

  • 标签: TRIANGULATION spline CAGD polygonal rational vertex
  • 简介:Thispaperderivesfirstordernecessaryandsufficientconditionsforunconstrainedconed.c.Programmingproblemswheretheunderlinedspaceispartiallyorderedwithrespecttoacone.Theseconditionsaregivenintermsofdirectionalderivativesandsubdifferentialsofthecomponentfunctions.Moreover,conjugatedualityforconed.c.Optimizationisdiscussedandweakdualitytheoremisprovedinamoregeneralpartiallyorderedlineartopologicalvectorspace(generalizingtheresultsin[11]).

  • 标签: 锥d.c.最优化 共轭对偶 弱对偶定理 次梯度 多目标优化 方向导数
  • 简介:Weintroducethenotionofproperty(RD)foralocallycompact,Hausdorffandr-discretegroupoidG,andshowthatthesetS2^l(G)ofrapidlydecreasingfunctionsonGwithrespecttoacontinuouslengthfunctionIisadensespectralinvariantandFreehet*-subalgebraofthereducedgroupoidC^*-algebraCr^*.(G)ofGwhenGhasproperty(RD)withrespecttol,sotheK-theoriesofbothalgebrasareisomorphicunderinclusion.EachnormalizedcoeycleconG,togetherwithaninvariantprobabilitymeasureontheunitspaceGoofG,givesrisetoacanonicalmapTconthealgebraCo(G)ofcomplexcontinuousfunctionswithcompactsupportonG.WeshowthatthemapTccanbeextendedcontinuouslytoS2^l(G)andplaysthesameroleasann-traceonCr^*(G)whenGhasproperty(RD)andcisofpolynomialgrowthwithrespecttol,sotheConnes'fundamentparingbetweentheK-theoryandthecycliccohomologygivesustheK-theoryinvariantsonCr^*(G).

  • 标签: GROUPOID C^*-algebra property (RD) SPECTRAL INVARIANCE
  • 简介:TheinteractionbetweenC60’sinsolidC60hasbeencalculatedby(exp-6-1)potential,andthecauseandthecontrolledfactorofthehighrapidrotationsofC60’swerediscussed.InordertodescribethedisordereddegreeofC60rotation,anequivalentMisintroduced.Thephasetransitionsatthe~260Kandatthe~90KarestudiedfromtheviewpointofC60rotation.Thepotentialbarriersoftheorderedrotationbelowthe~260Kandthedisorderedrotationabovethe~260Khavebeengiven,andtheeffectoftheexternalpressureonthetemperatureofphasetransitionhasalsobeengiven.

  • 标签: FULLERENE C60 MOLECULAR ROTATION phase TRANSITION
  • 简介:A.simplicialmesh(triangulation)isconstructedthatgeneralizesthetwo-dimensional4-directionmeshtoR~m.Thismesh,withsymmetric,shift-invariantvaluesatthevertices,isshowntoadmitaboundedC~1interpolantifandonlyifthealternatingsumofthevaluesattheverticesofany1-cubeiszero.Thisim-pliesthaiinterpolationattheverticesofanm-dimensional,simplicialmeshbyaC~1piecewisepolynomialofdegreem+1withonepiecepersimplexisunstable.

  • 标签: invariant INTERPOLATION TRIANGULATION PIECEWISE symmetric cube
  • 简介:LetAbeaunitalC*-algebra,n∈N∪{∞}.Itisprovedthattheisomorphism△n:Un0(A)/DUn0(A)→AffT(A)/△n0(π1(Un0(A)))isisometricforsomesuitabledistances.Asanapplication,theauthorhasthesplitexactsequence0→AffT(A)/△n0(π1(Un0(A)))iA→Un(A)/DUn(A)πA→Un(A)/Un0(A)→0withiAcontractive(andisometricifn=∞)undercertainconditionofA.

  • 标签: 迹空间 不变量 酉群 C^*代数 同胚群 等距群
  • 简介:Thispapergivesthedefinitionsandsomepropertiesofε-directionalderivateandε-subgradientsofcone-convexfunction.Fromthem,theoptimalityconditionsoflocalandglobaloptimalpointofunconstrainedcone-d.c.programmingaregained.Atlast,thedualitytheoremsofthisprogrammingarepresented.

  • 标签: ε-定向导出数 ε-子斜度 最优化条件 对偶定理 凸函数
  • 简介:在这篇论文,我们学习在订的复制Hilbert空格和它的复制内核之间的关系。对多项式与领先的学期产生的二个伪不变的潜水艇空格的一个类似、单一的等价的完全的描述被给。

  • 标签: 子空间 不变式 数学理论 计算方法
  • 简介:ThispaperdiscussestheidealstructureintensorproductABofC~*-algebraAandB,andintroducestheconceptofproperty(I)andproperty(K)withrespecttotheproblem.WhenAisanAF(orscattered)C~*-algebra,itisshownthatforanyC~*-algebraB,theidealsinABcanbeexpressedbythoseofAandB.

  • 标签: ALGEBRA TENSOR SCATTERED PROOF sided verify
  • 简介:ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].

  • 标签: FIRST DIRECT MEASUREMENT
  • 简介:MP3风靡我们的时候,我们就开始患上MP3疯魔症——眼睛睁开的第一秒,便搜索最爱的MP3,低头走路,孤立进食,默默无语……自始至终,活在一个人的世界里,你说,这不是疯了是怎么了?

  • 标签: MP3 设计 整机 电池