简介:LetGbeasecondcountablelocallycompactgroupoidwithHaarsystem{λuH},HbeaclosedsubgroupoidcontainingG^0withHaarsystem{λuH}.T.MasudaintroducedtheC^*-Groupoiddynamicsystem(G,A,α)anditsreducedcrossedproductCrea(G,A)in[2]:whereAisC^*-algebraαisthekomomorphismG→Aut(A).InthispapertheauthorintroducestheC^*-groupoiddynamicsystems(H,A,α/H)and(H\G2,A,^-α)inducedby(G,A,α)andprovesthatC*red(H,A)andC^*red(H\G^2,A)arestronglyMoritaequivalentMoreovertheinducedrepresentationfromC^*red(H,A)toC^*red(G,A)isgot.
简介:Risler&Trotmanin1997provedthatthemultiplicityofananalyticfunctiongermisleft-rightlipschitzinvariant,whichprovidedapartialanswertoZariskiconjecture.Inthisnote,basedontherecentworkofComte,Milman&Trotman,wegeneralizetheworkofthemtoprovethatthemultiplicityofaC~∞-differentiablefunctiongermisalsoleft-rightlipschitzinvariant.
简介:Anovelgas-phaseelectrocatalyticcellcontainingalow-temperatureprotonexchangemembrane(PEM)wasdevelopedtoelectrochemicallyconvertCO2intoorganiccompounds.TwodifferentCu-basedcathodecatalysts(CuandCu-C)werepreparedbyphysicalvapordepositionmethod(sputtering)andsubsequentlyemployedforthegas-phaseelectroreductionofCO2atdifferenttemperatures(70-90℃).ThepreparedelectrodesCuandCu-CwerecharacterizedbyX-raydiffraction(XRD),X-rayphotoemissionspectroscopy(XPS)andscanningelectronmicroscopy(SEM).Asrevealed,CuispartiallyoxidizedonthesurfaceofthesamplesandtheCuandCu-Ccathodiccatalystswerecomprisedofaporous,continuous,andhomogeneousfilmwithnanocrystallineCuwithagrainsizeof16and8nm,respectively.Theinfluenceoftheappliedcurrentandtemperatureontheelectro-catalyticactivityandselectivityofthesematerialswasinvestigated.Amongthetwoinvestigatedelectrodes,thepureCucatalystfilmshowedthehighestCO2specificelectrocatalyticreductionratesandhigherselectivitytomethanolformationcomparedtotheCu-Celectrode,whichwasattributedtothehigherparticlesizeoftheformerandlowerCuO/Curatio.Theobtainedresultsshowpotentialinterestforthepossibleuseofelectrical「enewableenergyforthetransformationofCO2intovaluableproductsusinglowmetalloadingCubasedelectrodes(0.5mgCucm2)preparedbysputtering.
简介:目的:为使零件在设计阶段实现公差的自动分配,研究线轮廓度在计算机中的表达模型。创新点:1.提出一种新的构建线轮廓度公差T-Map图的方法;2.用运动学等效的方法表示理想轮廓公差域的允许偏差。方法:1.将零件轮廓分解成多段,然后分别为每段生成一个实体模型T-Map(图6和7);2.利用布尔交运算将所有分段T-Map合成一个完整线轮廓度的T-Map(图8);3.以弧形短槽为例,演示创建线轮廓度的方法步骤。结论:将弧形短槽轮廓分成多段,先实现每一段的T-Map,再利用布尔交实现整体线轮廓度公差的T-Map图,证明该方法在构建任意轮廓的线轮廓度公差上的有效性。
简介:WehavesynthesizedandinvestigatedphysicalpropertiesoftwonewquaternarycompoundsGd2CoAl4T2(T=Si,Ge)singlecrystals,whichareisostructuraltoTb2NiAl4Ge2andEr2CoAl4Ge2.Themostimportantstructuralfeatureofthesematerialsistheanti-CaF2-typeCoAl4T2slabs.Thesematerialsshowmetallicbehaviorbelow300Kandthereisalong-rangeantiferromagnetic(AFM)transitionappearingat20and27KforGdCoAl4Ge2andGd2CoAl4Si2,respectively.ResistivityandheatcapacitymeasurementsalsoconfirmthesebulkAFMtransitions.Furtheranalysisindicatesthatthislong-rangeantiferromagnetismshouldresultfromthemagneticinteractionbetweenlocalmomentsofGd^3+ions.
简介:本文用临界点理论中的能量最小原理得到了一类具(q(t),P(t))-Laplacian项的二阶非自治系统存在周期解的充分条件.
简介:ThispapershowsthattheC1-curvedfiniteelementdevelopedbyBernadoningeneralcannotsatisfytheessentialboundaryconditionsonapproximateboundary.Furthermore,amodifiedC1-curvedfiniteelementisgiven,whichiscompatiblewiththeelementofArgyristriangleandcansatisfythehomogeneousDirichletboundaryconditionsonapproximateboundary.
简介:C19-DITERPENOIDALKALOIDSOFDELPHINIUMMOLLIPILUM¥SuoMingZHANG;QingYuOu(LanzhouInstituteofChemicalPhysics,ChineseAcademyofSci?..
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.
简介:TheCprogramminglanguageisexpressiveandflexible,butnotsafe;asitsexpressivepowerandflexibilityareobtainedthroughunsafelanguagefeatures,andimproperuseofthesefeaturescanleadtoprogrambugswhosecausesarehardtoidentify.SinceCiswidelyused,anditisimpracticaltorewriteallexistingCprogramsinsafelanguages,sowaysmustbefoundtomakeCprogramssafe.ThispaperdealswiththeunsafefeaturesofCandpresentsasurveyonexistingsolutionstomakeCprogramssafe.Wehavestudiedbinary-levelinstrumentationtools,sourcecheckers,source-levelinstrumentationtoolsandsafedialectsofC,andpresentacomparisonofdifferentsolutions,summarizedthestrengthsandweaknessesofdifferentclassesofsolutions,andshowmeasuresthatcouldpossiblyimprovetheaccuracyoralleviatetheoverheadofexistingsolutions.
简介:ThispaperintroducestheconceptoflocalC-cosins-familyandinverstigateitsbasicproperties,Inparticular,acharacterizationofthecompleteinfinitesimalgeneratorofalocalC-cosinefamilyisobtained,AsanapplieationofthistheorytothesecondordersbstractCauchyproblems,acharacterizationofthelocalC-well-posednessoftheseproblemsisgivenintermsofthelocalC-cosinefamilytheory.
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∈
简介:Thispaperderivesfirstordernecessaryandsufficientconditionsforunconstrainedconed.c.Programmingproblemswheretheunderlinedspaceispartiallyorderedwithrespecttoacone.Theseconditionsaregivenintermsofdirectionalderivativesandsubdifferentialsofthecomponentfunctions.Moreover,conjugatedualityforconed.c.Optimizationisdiscussedandweakdualitytheoremisprovedinamoregeneralpartiallyorderedlineartopologicalvectorspace(generalizingtheresultsin[11]).
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).