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简介：DigitaldecayspectroscopyofactinideisotopesatthegasfilledseparatorSHANSAlloverthechartofnuclides,theregiontothe“north-east”of208Pb,withZ≥84andN=128~130,hoststheshortest-livedαradioactivities,withhalf-livesintherangeofnanosecondstomicroseconds.Synthesisanddetectionofneutron-deficientisotopesabovethoriuminthisregionarechallengingduetotheirlowproductioncrosssectionsandshorthalf-lives.

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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：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.

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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.

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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.

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简介：ＲｅｃｏｉｌＲａｎｇｅｓｏｆＮｅａｒ－ｔａｒｇｅｔＰｒｏｄｕｃｔｓｆｒｏｍ５０ＭｅＶ／ｕ１８Ｏ＋１９７Ａｕ￥ＹａｎｇＹｏｎｇｆｅｎｇ；ＺｈａｏＺｈｉｚｈｅｎｇ；ＬｉＺｏｎｇｗｅｉ；ＺｈｕＳｈａｏｆｅｉ；ＣａｔＸｉｃｈｅｎｇ；Ｙａ...

简介：ＡｃｔｉｖａｔｉｏｎＭｅａｓｕｒｅｍｅｎｔｓｏｆＮｅｕｔｒｏｎＤｏｓｅＥｑｕｉｖａｌｅｎｔＲａｔｅｓｉｎ５０ＭｅＶ／ｕ￣（１８）Ｏ－ｉｏｎＴａｒｇｅｔＡｒｅａ￥ＬｉＧｕｉｓｈｅｎｇ；ＺｈａｎｇＴｉａｎｍｅｉ；ＬｉＺｏｎｇｗｅｉａｎｄＳｕＹｏｕｗｕＮｅ...

简介：近代科学进入中国之回顾与前瞻──诺贝尔奖获得者杨振宁博士１９９４年８月１８日在南宁的演讲有机会同大家讨论近代科学进入中国之回顾与前瞻，我很高兴。今天我要谈的是，近代科学如何发源于西方，随后又怎样进入中国的经过。了解这个过程以后，我们就能够对今天中华民...

简介：基于介观电路中电荷的量子化特性和介观电容中存在弱耦合效应的物理事实,对介观LC电路进行了量子力学处理,并讨论了电路中的类超导电流的量子特性。结果表明:无源情形时介观LC电路中类超导电流随时间变化具有周期性,其平均值为零;在直流稳压电源的作用下类超导电流存在直流分量,总电流平均值存在shapiro台阶;在交流电源的作用下类超导电流也可以存在直流分量,但总电流平均值不存在Shapiro台阶。

简介：利用蒙特卡洛方法分析了不同束流密度0.8MeV电子辐照下介电材料导电性能的变化趋势,同时开展了0.8MeV电子辐照下聚酰亚胺(Kapton)材料导电性能实验研究.理论和实验结果表明,在0.8MeV电子辐照后,Kapton材料导电性能在不同吸收剂量率下变化较大,电导率最大可上升5个量级,电阻由1014Ω变为1012Ω,下降2个量级.

简介：以PbO，MgO，Nb2O5，TiO2为原料，采用两步固态反应法制备了纯钙钛矿相的0．92PMN-0．08PT陶瓷，并对其相的组成、微观形貌、介电性能和储能性能进行了研究。在25℃，1kHz条件下，该陶瓷的相对介电常数高达27480，介电损耗tan艿仅为4％，电滞回线形状细长，剩余极化很小，可释放的能量密度达0．31J·cm-3.结果表明：室温下该陶瓷具有优良的介电和储能性能。

简介：在超球坐标中,用类氢波函数基展开来计算电子偶素负离子(PS~-)系统的基态能量,然后用基态波函数计算体系的形状密度,从而确定基态的几何结构。

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