简介：Inthispaper,blendmembranesfrompolyvinylacetate(PVAc)andblockcopolymerpoly(amide-12-b-ethyleneoxide)(Pebax1074)arepreparedbysolutioncastingandsolventevaporationmethod.Althoughtheyarehomogeneousonamacro-scale,theobservationsfromDSCandSEMindicatemicro-phaseseparationforPVAc/Pebax1074blendmembranes.WiththeincreaseofPebax1074content,gaspermeabilitiesofCO2,H2,N2andCH4allincreasegreatly.PVAc/Pebax1074blendmembraneswithhighPVAccontentareappropriateforCO2/CH4separation.Thetemperaturedependenceofgaspermeabilityisdividedintorubberyregionandglassyregion.Theactivationenergiesofpermeationinrubberyregionaresmallerthanthoseinglassyregion,andtheyalldecreasewithincreasingPebax1074content.ForN2,H2andCH4,theirgaspermeationpropertiesaremainlyinfluencedbythedual-modesorptionandhydrostaticpressureeffect.ButforCO2,itspermeabilityincreaseswiththeincreaseofpressureduetoCO2-inducedplasticizationeffect,whichismoreobviousforPVAc/Pebax1074blendmembraneswithhighPVAccontent.

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

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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.

简介：Theoreticalmodelsofstellarevolutionpredictnegligiblequantitiesof6Li,9Be,and11Binthehydrogenburningphasesofastar’sevolution[1].TheprimordialBig-Bangnucleosynthesis(BBN)modelmightbemoregenerousinitsproductionoftheseelements[2].Theradiative-capturecrosssectionforprotoncaptureon11Bleadingto12CissmallatastrophysicallyinterestingenergiesbecauseofthelargeCoulombbarrier.

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

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