简介:DigitaldecayspectroscopyofactinideisotopesatthegasfilledseparatorSHANSAlloverthechartofnuclides,theregiontothe“north-east”of208Pb,withZ≥84andN=128~130,hoststheshortest-livedαradioactivities,withhalf-livesintherangeofnanosecondstomicroseconds.Synthesisanddetectionofneutron-deficientisotopesabovethoriuminthisregionarechallengingduetotheirlowproductioncrosssectionsandshorthalf-lives.
简介:Thephotonpolarizationtensorcarriesthefundamentalinformationofmagnetizedvacuumormedium[1{5].Acompletedescriptionofthevacuumpolarizationtensorisparticularlycomplicatedtoapproach,sincethevacuumphotonpolarizationtensorisexpressedintermsofadoublesummationofinfiniteserieswithrespecttotwoLandaulevelsoccupiedbyvirtualchargedparticles.MostworkswerefocusingonthestrongfiledlimitwithanassumptionofLowestLandauLevel(LLL)[2,6]InRef.[7]weobtainedafulldescriptionofvacuumpolarizationtensorinresponsetoalltheLandaulevelsatanyfieldstrengthofBforthefirsttimebeyondLLLapproximation,andwefoundoutthattheimaginarypartofthephotonpolarizationtensorξΠbecomesnonzeroatthetimelikemomentaregionQ2>4(M2+2neB)atT=0,i.e..,theLLLapproximationisanalyticallysatisfied[3,7].
简介:Thenovelcomplex[K(18-C-6)]2[Cd(mnt)2][18-C-6-18-crown-6,nmt=1,2-dicyanoethene-1,2-dithiolate,C2S2-(CN)2^2-]wassynthesizedandcharacterizedbyelementalanalysis,IRspectrumandX-raydiffractionanalysis.Thecomplexdisplaystwo-dimensionalnetworkstructureof[K(18-C-6)]complexsegmentsand[Cd(nmt)2]complexsegmentbridgedbyS-K-S,S-K-NandN-K-Ninteractionsbetweenadjacent[K(18-C-6)]and[Cd(mnt)2]units.
简介:HIRFL-CSRacceleratorfacilityhasbeenoperatingwith3ionsources,whichareLAPECR1,LECR3andSECRAL.Theseionsourcescanprovidedifferentkindsofionswithdifferentenergy.Forexample,LAPECR1mainlyprovidesH+andHe+witheextractionvoltageabove25keV,LECR3canprovidetheionbeamswithlowtomediumchargestates,includingthemetallicionswithlowmass,suchasC^4+,Ar^11+,B^3+,Mg^7+,etc.,whileSECRALaimstoproduceintenseandhighlychargedionbeams,especiallymetallicones,suchlikeKr^19+,Xe^31+,Ni^19+,Bi^31+,U^33+,andsoon.
简介:Twonewdicyanamidecoordinationpolymers,{Mn(dmpz)[N(CN)2]2}2(1)and{Cu(dmpz)[N(CN)2]2}2(2)(dmpz=3,5-dimethylpyrazole),weresynthesizedandcharacterizedbysinglecrystalX-raydiffractionanalysisandIRspectroscopy.In1and2themetalionshavetwodifferentcoordinationmodes,whereoneiscoordinatedtofourdicyanamideanionsandtwomonodentatedmpzmoleculestoformaslightlydistortedoctahedralgeometry,whiletheotheradoptsoctahedralgeometry,surroundedbyfournitrileNatomsandtwoamideNatomsofthedicyanamideanions.Bothcomplexescontaintwoalternatingchainsthatareparalleltoeachother.
简介:ToanalyzetheantitumorpotentialandmechanismofactionofsimultaneousNewcastlediseasevirus(NDV)hemagglutinin-neuraminidase(HN)andhumaninterleukin18(hIL-18)genetransferinC57BL/6micewithH22hepatoma,themousemodelwithH22hepatomawasestablishedinC57BL/6mice,andtheantitumoreffectsofthecombinedapplicationofNDVHNandhIL-18wereevaluatedinvivo.Theresultsshowthatthegrowthofestablishedtumorsinmiceimmunizedwithadenovirus(Ad)-HNinconjunctionwithAd-hIL-18wassignificantlyinhibitedcomparedwiththatinmiceimmunizedwithAd-HN,Ad-hIL-18alone,ortheemptyvector(Ad-mock).Furthermore,theimmunizationofmicewithAd-HNinconjunctionwithAd-hIL-18elicitedstrongnaturalkilleractivityandH22tumor-specificcytotoxicTlymphocyte(CTL)responsesinvivo.Inaddition,TcellsfromthelymphnodesofmiceimmunizedwithAd-hIL-18orAd-HN+Ad-hIL-18secretedhighlevelsoftheTh1cytokineIL-2andinterferon-γ(IFN-γ),indicatingthattheregressionoftumorcellsisrelatedtoaTh1-typedominantimmuneresponse.TheseresultsdemonstratethatvaccinationwithNDVHNtogetherwithhIL-18maybeanovelandpowerfulstrategyforcancerimmunotherapy.
简介:ThespectrumoftheΣ(1193)excitedstates,Σ,withisospinI=1andstrangenessS=??1isoneofthemostimportantissuesinhadronicphysics.TheΣresonancesaremostlyproducedandstudiedinK-inducedreactions.ManyΣresonancesarenowcatalogedbytheParticleDataGroup[1].However,ourknowledgeoftheseresonancesisstillverypoor.Intheenergyregionbelow2GeV,onlyafewofthemarewellestablished,suchastheΣ(1385)ofspin-parityJP=3=2+,Σ(1670)ofJp=3=2??andΣ(1775)ofJp=5=2??.Theothersarenotwellestablishedandsomeofthemareevenoflargeuncertaintiesontheirexistence.Thus,thestudyoftheΣresonancewiththeavailableexperimentaldataisnecessary.
简介:ExperimentalMeasurementsofNeutronDistributionsin50MeV/u18O+Be,CuandAuReactions¥LiGuisheng;ZhangTianmei;LiZongweiandSuYouwu?..
简介:Muscovitemicasheetswithathicknessof12mwereirradiatedbyswiftheavyionsKrandBifromHeavyIonResearchFacilityinLanzhou(HIRFL).Theuencesrangefrom11010to11012ions/cm2.Theelectronicenergyloss(dE/dx)eincreasesfrom5.9to31.5keV/nm.ThevibrationalmodicationsinirradiatedmicawereinvestigatedbyFourier-transforminfraredspectroscopyandthelatenttrackswereobservedbytransmissionelectronmicroscope(TEM).Theinfraredspectrumshowsthatmotionsfromallatomtypesinthemuscovitemicastructurecouldbefoundinmodesforallvibrations.AsshowninFig.1,theintensityofallvibrationalmodesinmica,includingtheOHstretchmotionat3621cm??1,decreasedwiththeincreasing(dE/dx)e.Thesimilartendencyisfoundinsamplesirradiatedbyswiftheavyionswithincreasingionuence.Itisindicatedthatdefectsandstructuralmodicationsgeneratedduringswiftheavyionirradiation,andmoredefectsareintroducedbyirradiationwithhigherionuence.
简介:Twoseriesofmixedoxides,CoAlMandMgAlM(M=Cr,Mn,Fe,Co,Ni,Cu),werepreparedbycalciningtheircorrespondinghydrotalcite-likecompounds(HTLc).TheratioofMg:Al:M(orCo:Al:M)was3:1:1.ThecatalyticactivityofallsamplesforthereactionofNO+COwasinvestigated.TheresultsshowedthattheactivityofCoAlMwasmuchhigherthanthatofMgAlM.ThestructureandthepropertyofredoxwerecharacterizedbyXRDandH2-TPR.TheresultsindicatedthatonlyMgOphasewasobservedaftercalciningMgAlMhydrotalcites,andthetransitionmetalsbecamemorestable.Thespinel-likephaseappearedinallofCoAlMsamplesafterthecalcination,andthetransitionmetalswerechangedtobemoreactive,andeasilyreduced.TheactivitiesofthreeseriesofmixedoxidesCoAlCuobtainedfromdifferentpreparationmethods,differentratioofCo:Al:Cuandatdifferentcalcinationtemperatures,werestudiedindetailforproposingthemechanismofreaction.TheabilityofadsorptionofNOandCO
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简介:UsingthedensityfunctionaltheoryandthenonequilibriumGreen’sfunctionmethod,westudiedthefinite-biasquantumtransportinaCr/graphene/Crmagnetotunneljunction(MTJ)constructedbyasinglegraphenelayersandwichedbetweentwosemi-infiniteCr(111)electrodes.Wefoundthatthetunnelingmagnetoresistance(TMR)ratiointhisMTJreached108%,whichisclosetothatofaperfectspinfilter.Underanexternalpositivebias,wefoundthattheTMRratioremainedconstantat65%,incontrasttoMgO-basedMTJs,theTMRratiosofwhichdecreasewithincreasingbias.TheseresultsindicatethattheCr/graphene/CrMTJisapromisingcandidateforspintronicsapplications.