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  • 简介:Inthisarticle,wecalculatethecontributionfromthenonfactorizablesofthadronicmatrixelementtothedecayB~0→χc1~π~0withthelight-conequantumchromo-dynamic(QCD)sumrules.Thenumericalresultsshowthatitscontributionisratherlargeandshouldnotbeneglected.Thetotalamplitudesleadtoabranchingfractionwhichisinagreementwiththeexperimentaldatamarginally.

  • 标签: QCD求和规则 衰变 计算结果 强子矩阵元 实验数据 动力学
  • 简介:Thermoelectricityisatherrnorelatedpropertythatisofgreatimportanceinsingle-moleculejunctions.Theelectricalconductance(σ),electron-derivedthermalconductance(kel)andSeebeckcoefficient(S)ofBgo-basedsingle-moleculejunctionsareinvestigatedbyusingdensityfunctionaltheoryincombinationwithnon-equilibriumGreen'sfunction.Whenthedistancebetweentheleft/rightelectrodesis11.4A,therelationshipbetweenσandkelobeystheWiedemann-FranzlawverywellbecauseofthestronghybridizationbetweenB80molecularorbitalsandthesurfacestatesofAuelectrodes.Furthermore,thecalculatedLorenznumberisclosetothefamousvalueinmetalordegeneratesemiconductors.Inaddition,Sisonly—19.09μV/Kat300K,thusleadingtothesmallerelectron'sthermoelectriefigureofmerit(ZeiT=S^2σT/Kel).Interestingly,thestrainandchemicalpotentialcanmodulateB80-basedsingle-moleculejunctionsfromn-typetop-typewhenthecompressivestrainreaches—0.6Aorthechemicalpotentialshiftsto—0.16eV.ThismightbeattributedthatSreflectstheasymmetryintheelectricalconductancewithrespecttothechemicalpotentialandisproportionaltotheslopesofthetransmissionspectrum.

  • 标签: THERMOELECTRICITY SINGLE-MOLECULE JUNCTION NON-EQUILIBRIUM Green FUNCTION
  • 简介:Theoreticalmodelsofstellarevolutionpredictnegligiblequantitiesof6Li,9Be,and11Binthehydrogenburningphasesofastar’sevolution[1].TheprimordialBig-Bangnucleosynthesis(BBN)modelmightbemoregenerousinitsproductionoftheseelements[2].Theradiative-capturecrosssectionforprotoncaptureon11Bleadingto12CissmallatastrophysicallyinterestingenergiesbecauseofthelargeCoulombbarrier.

  • 标签: FACTORS LOW ENERGIES
  • 简介:Underinvestigationinthispaperisa(3+1)-dimensionalvariable-coefficientKadomtsev–Petviashviliequation,whichdescribesthepropagationofsurfaceandinternalwaterwaves.ByvirtueofthebinaryBellpolynomials,symboliccomputationandauxiliaryindependentvariable,thebilinearforms,solitonsolutions,B¨acklundtransformationsandLaxpairareobtained.Variablecoefficientsoftheequationcanaffectthesolitonicstructure,whentheyarespeciallychosen,whilecurvedandlinearsolitonsareillustrated.Elasticcollisionsbetween/amongtwoandthreesolitonsarediscussed,throughwhichthesolitonskeeptheiroriginalshapesinvariantexceptforsomephaseshifts.

  • 标签: LAX对 变系数 孤立波解 方程 BACKLUND变换 双线性形式