简介:Veryrecently,BelleannouncedtheirobservationofΥ(5S)!bJ!(J=0;1;2),indicatingthattheΥ(5S)!bJ!decaysalsohavelargedecaywidths,i.e.,themeasuredbranchratiosofΥ(5S)!bJ!are<3:410??3,(1:640:23+0:30??0:22)10??3,and(0:570:220:07)10??3withJ=0;1;2,respectively[1].ItshouldbenoticedthateventhoughthetreelevelcontributionstoΥ(5S)!bJ!(J=0;1;2)shouldbestronglysuppressedduetotheOkubo-Zweig-Iizuka(OZI)rule,suchlargedecaywidthsareobserved,whichagaininspiresourinterestinunderstandingsuchquantities.Inthiswork,weproposethatthecontributionfromthehadronicloopshouldbeconsideredinstudyingΥ(5S)!bJ!.
简介:用Co2(CO)8与CH3CSNH2反应制得产物Ⅰ,又用Na2Fe(CO)4与Ⅰ反应制得产物Ⅱ(Ⅰ:Co3(μ3-S)(CO)7(CH3CSNH),Ⅱ:Co2Fe(μ3-S)(CO)7(CH3CSNH).通过元素分析。IR、UV、1HNMR、MS表征并用X射线衍射法测得Ⅱ的单晶结构.该簇合物属三斜晶系、PT空间群,晶胞参数:a=0.9203(1),b=1.1296(2),c=1.1425(2)nm;α=116.40°(2),β=101.92°(2),γ=92.58°(1);z=2,V=1.2162nm3,Dc=1.698cm3,μ=21.89cm-1.结构分析表明,Co2FeS构三角锥分子骨架,所有CO均为端基配体,S1为面桥基配体,CH3CSNH为双齿配体,与Co、Fe形成五元环结构.
简介:WehavedepositedW/Simultilayermirrorsusingthemagnetronsputteringunderthelowsputteringpressureandthehighmagneticfieldstrength,andmeasuredtheirreflectivtityinBeijingsynchrotronradiationfaciltiy,W/Simultilayershowthepeakreflectivityofapproximately10%ataphotonenergyof1200eVand10.5%ataphotoenergyof700eVrespectivelyattheincidenceangleof81°。
简介:Inthispaper,withPoincare’sformalism,andanindirectmethod,thecanonicalformsofthegeneralizedequationsofmotionduetoNielsenandCenovofaholonomicdynamicalsysteminthevelocity-phasespaceandtheacenleration-phasespaceareobtainedintermsofthePoincareparameters.
简介:在这份报纸,在范围的稳定的homotopy组的homotopy元素的一个新家庭由n2m5and3s代表了
简介:Weproveseveralinequaliesforsymmetricpostivesemidefinite,generalMmatricesandinverseM-matriceswhicharegeneralizationoftheclassicalOppenheim'sInequalityforsymmetricpositivesemidefinitematrices.
简介:TheauthorfirstreviewstheclassicalKorninequalityanditsproof.FollowingrecentworksofS.Kesavan,P.Ciarlet,Jr.,andtheauthor,itisshownhowtheKorninequalitycanberecoveredbyanentirelydifferentproof.ThisnewproofhingesonappropriateweakversionsoftheclassicalPoincar'eandSaint-Venantlemma.Infine,bothproofsessentiallydependonacruciallemmaofJ.L.Lions,recalledatthebeginningofthispaper.
简介:TheextendedcanonicalNoetheridentitiesandcanonicalfirstNoethertheoremderivedfromanextendedactioninphasespaceforasystemwithasingularLagrangianareformulated.UsingthesecanonicalNoetheridentities,itcanbeshownthattheconstraintmultipliersconnectedwiththefirst-classconstraintsmaynotbeindependent,soaquerytoaconjectureofDiracispresented.BasedonthesymmetrypropertiesoftheconstrainedHamiltoniansysteminphasespace,acounterexampletoaconjectureofDiracisgiventoshowthatDirac'sconjecturefailsinsuchasystem.WepresenthereadifferentwayratherthanCawley'sexamplesandother'sonesinthatthereisnolinearizationofconstraintsintheproblem.Thisexamplehasafeaturethatneithertheprimaryfirst-classconstraintsnorsecondaryfirst-classconstraintsaregeneratorsofthegaugetransformation.