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简介：Wehavedevelopedanewradiographysetupwithashort-pulselaser-drivenx-raysource.Usingaradiographyaxisperpendiculartobothlong-andshort-pulselasersallowedoptimizingtheincidentangleoftheshort-pulselaseronthex-raysourcetarget.Thesetuphasbeentestedwithvariousx-raysourcetargetmaterialsanddifferentlaserwavelengths.Signaltonoiseratiosarepresentedaswellasachievedspatialresolutions.ThehighqualityofourtechniqueisillustratedonaplasmaflowradiographobtainedduringalaboratoryastrophysicsexperimentonPOLARs.

简介：为了分析电流型CdZnTe（CZT）探测器的脉冲线性,利用CZT探测器测量得到了脉冲宽度为50ns的脉冲X射线响应曲线,采用波形时间积分法分析了其线性特性。结果表明,以波形时间积分为测量目标量,当X射线照射量在0.160-0.826mR范围时,在10%的不确定度范围内,样品探测器可作为线性测量系统的探测器件;以幅值为测量目标量,工作电压为400V时,在5%的不确定度范围内,样品探测器可作为线性测量系统的探测器件。

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简介：Inthisarticle,wetaketheX(5568)asthediquark-antidiquarktypetetraquarkstatewiththespin-parityJ~P=0~+,constructthescalar-diquark-scalar-antidiquarktypecurrent,carryouttheoperatorproductexpansionuptothevacuumcondensatesofdimension-10,andstudythemassandpoleresidueindetailswiththeQCDsumrules.WeobtainthevalueM_X=(5.57±0.12)GeV,whichisconsistentwiththeexperimentaldata.ThepresentpredictionfavorsassigningtheX(5568)tobethescalartetraquarkstate.

简介：TheelectronicpropertiesandtopologicalphasesofThXY(X=Pb,Au,Pt,PdandY=Sb,Bi,Sn)compoundsinthepresenceofspin–orbitcoupling,usingdensityfunctionaltheoryareinvestigated.TheThPtSncompoundisstableintheferromagneticphaseandtheotherThXYcompoundsarestableinnonmagneticphases.Bandstructuresofthesecompoundsintopologicalphases(insulatorormetal)andnormalphaseswithingeneralizedgradientapproximation(GGA)andEngel–Voskogeneralizedgradientapproximation(GGAEV)arecompared.TheThPtSn,ThPtBi,ThPtSb,ThPdBi,andThAuBicompoundshavetopologicalphasesandtheotherThXYcompoundshavenormalphases.Bandinversionstrengthsandtopologicalphasesofthesecompoundsatdifferentpressurearestudied.Itisseenthatthebandinversionstrengthsofthesecompoundsaresensitivetopressureandforeachcompoundasecond-orderpolynomialfittedonthebandinversionstrengths–pressurecurves.

简介：采用直流X射线连续能谱照射晶体,以极小的步进角,测量一定角度范围内,不同入射角度下的衍射能谱,通过提取各个角度衍射能谱中同一能量X射线的衍射强度,微分得到该能量的平晶摇摆曲线。与传统测量方法相比,该方法具有更大的X射线能量测量范围,可通过一次角度扫描,同时给出多个能量的摇摆曲线。利用该方法开展了16~21keV区间内LiF（200）平晶摇摆曲线的相对强度标定,结果表明,晶体摇摆曲线的半高宽随X射线能量增加而缓慢减小,而峰值强度随X射线能量增加则缓慢增加,在入射能谱强度变化较大区间内,该方法测量结果的不确定度较大。

简介：Fe_(3–x)O_4raspberryshapednanostructures/graphenenanocompositesweresynthesizedbyaone-steppolyol-solvothermalmethodtobetestedaselectrodematerialsforLi-ionbattery(LIB).Indeed,Fe_(3–x)O_4raspberryshapednanostructuresconsistoforiginalorientedaggregatesofFe_(3–x)O_4magnetitenanocrystals,ensuringalowoxidationstateofmagnetiteandahollowandporousstructure,whichhasbeeneasilycombinedwithgraphenesheets.TheresultingnanocompositepowderdisplaysaveryhomogeneousspatialdistributionofFe_(3–x)O_4nanostructuresatthesurfaceofthegraphenesheets.TheseoriginalnanostructuresandtheirstronginteractionwiththegraphenesheetsresultedinverysmallcapacityfadinguponLi+ionintercalation.Reversiblecapacity,ashighas660mAh/g,makesthismaterialpromisingforanodeinLi-ionbatteriesapplication.

简介：WehavestudiedtheangularmagnetoresistanceofironpnictidesBaFe2-xNixAs2,whichshowsclear180degreeperiodicityasfittedbyacosinefunction.Inthex=0.065sample,thephaseofthetwo-foldsymmetrychanges90degreesabovethetetragonal-to-orthorhombicstructuraltransitiontemperatureTs.Sincethephaseatlowtemperatureisassociatedwiththerotationoforthorhombicdomainsbymagneticfield,weshowthatevenvacuumgreasecanpushthepresenceoforthorhombicdomainsattemperaturesmuchhigherthanTs.Ourresultssuggestthatresidualstressmayhavesignificanteffectsinstudyingthenematicordersanditsfluctuationsinironpnictides.

简介：Twotransmissioncurvedcrystalspectrometersaredesignedtomeasurethehardx-rayemissioninthelaserfusionexperimentofComptonradiographyofimplosiontargetonShenGuang-IIIlaserfacilityinChina.Cylindricallycurvedα-quartz(10–11)crystalswithcurvatureradiiof150and300mmareusedtocoverspectralrangesof10–56and17–100keV,respectively.Thedistancebetweenthecrystalandthex-raysourcecanbechangedoverabroaddistancefrom200to1500mm.Theopticaldesign,includingtheintegralreflectivityofthecurvedcrystal,thesensitivity,andthespectralresolutionofthespectrometers,isdiscussed.WealsoprovidemechanicdesigndetailsandexperimentalresultsusingaMoanodex-raysource.High-qualityspectrawereobtained.Weconfirmedthatthespectralresolutioncanbeimprovedbyincreasingtheworkingdistance,whichisthedistancebetweentherecordingmediumandtheRowlandcircle.

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：TheGroupofNuclearStructureResearchatIMPhasdevotedmuchefforttothestudyofin-beam-rayspectroscopyandγ-decayspectroscopy.Oneterminalforin-beam-rayspectroscopyhasbeennewlybuiltupin2016.Asforγ-decayspectroscopy,twopointsneedtobeemphasized.Inordertostudythein-beam-rayspectroscopy,aballwasplacedattheterminalofnewTL2beamline.Threequadrupolemagnetsfollowingthedipolemagnetarethemainbuildingblocksalongthebeamline.Theballconsistsof8cloverand16HPGedetectorswithaCsIballinsidetoselectthechargedparticlechannel.Awallisolatingtheballfromthequadrupoleswasusedtoshieldtheradiationproducedbytheacceleratoranddepositingenergyinthedetectors,whichmayresultinahighbackground.Theinstallationwasfinishedin2016andtheexperimentforin-beam-rayspectroscopyisexpectedtoperformin2017.

简介：雷纳兹应力(RS)上的积极偏爱的效果和它在边血浆的光线的狂暴的运输上的效果(r/a?=?0.9)并且在tokamak的血浆的擦去层(太阳)区域被调查。光线并且poloidal电场(Er,Ep)和离子浸透电流(我s)被多种用途的探查(MPP)测量。这根探针在IR-T1tokamak第一次被制作并且构造。这根探针的大多数优点是Er和Ep能在单个射击在不同半径被测量。因此不同半径的信息能与高精确相比。偏爱电压在V偏爱?=?200V和它与在r/a被修理的limiter偏爱被使用了?=?0.9。而且，之间的阶段差别光线并且MPP检测的RS光谱的poloidal电场，和时间的进化被计算。边上的RS大小(r/a?=?0.9)多于它在太阳的价值(r/a?=?1.02)。与应用偏爱200V，RS和Er和Ep被增加，当光线的狂暴的运输同时被减少时。因此，RS影响光线的骚乱，这能被结束。RS光谱的时间的进化证明RS的频率在r/a被增加并且到达它的最高的价值?=?0.9面对偏爱。

简介：Ithasbeenproposedthatfusionreactionsbetweenneutron-richlightnuclei,forexample24C,24Oand28Ne,maycontributetoachievingtheignitiontemperatureforexplosivecarbonburningprocessduringsuperbusrsts[1,2].Studiesoffusionreactionsinvolvingneutron-richnucleiarebeyondordinaryexperimentaltechniques,sincetheintensityofradioactivebeambecomelowforthesemeasurements[3].TheactivetargettechniqueusingTPC(TimeProjectionChamber),withpropertiesofmulti-sampling,highefficiencyandlowbackground,isasuitablesolutiontotheproblem.

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简介：HighlytexturedHeusleralloyMn46Ni42Sn11Sb1ribbonswerepreparedbymeltspinning.TheannealedhighMncontentMn46Ni42Sn11Sb1ribboncross-sectionmicrostructure,crystalstructure,martensitictransformation（MT）,andmagnetoresistance（MR）propertieswereinvestigated.TheMRintheannealedribbonwasassessedbythemagneticfielddirectionperpendiculartotheribbonsurfacewiththemagneticfieldupto30kOe.Thelargenegativevalueof25%forMRwasobtainedat244K.Theexchangebias（EB）effectsoftheas-spunandannealedribbonswereinvestigated.Afterannealing,theEBeffectshavebeenimprovedbyabout25Oeatthetemperatureof50K.Themagnetizationshaveincreasedapproximatelyby10%morethantheas-spunribbon.