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70 个结果
  • 简介:在中微子实验不断取得进展,量子场论找到其预言的最后一个粒子——希格斯子的今天,回顾它们的缘起β衰变能量连续谱的发现历史,既为了纪念这段历史,也为了可以从中讨论关于物理学的研究线路具有不明确性、物理学的研究发现与研究者流动的相关性、物理学的发现需要适当的思想准备和物理学研究时做些哲学反思的必要性等方面获得启示。

  • 标签: Β衰变 能量连续谱 发现 证实 启示
  • 简介:Thescientificprogramofthegroupcoversbigbangnucleosynthesis,hydrostaticburninginstarsandexplosivenucleosynthesisinsupernova.Byconsideringnon-equilibriumstatistics,wesuggestapossiblewaytosolvetheLiprobleminbigbangnucleosynthesis.The13C(α,n)16Oisthemajorneutronsourceforthes-processhappeninginAGBstars.The19F(p,α)16Oisrelevanttotheproductionoffluorine.WearedevelopingexperimentalplatformstostudytheimportantreactionforthefirsttimedirectlyattheirstellarenergiesinJinpingUndergroundLaboratory.The59Festellardecayrateisimportantfortheproductionof60Fe,animportantisotopewhosegammarayhasbeenobservedbysatellites.WedetermineitsstellardecayrateforthefirsttimeusingexperimentalB(GT)strength.Thenewratereducesthediscrepancyofthe60Feyieldsbetweenthemodelpredictionsandtheobservations.Theundergroundexperimentisexpectedtobeginin2018.

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  • 简介:TheobjectiveoftheApollon10PWprojectisthegenerationof10PWpeakpowerpulsesof15fsat1shotmin-1.InthispaperabriefupdateonthecurrentstatusoftheApollonprojectispresented,followedbyamoredetailedpresentationofourexperimentalandtheoreticalinvestigationsofthetemporalcharacteristicsofthelaser.Morespecificallythedesignconsiderationsaswellasthetechnologicalandphysicallimitationstoachievetheintendedpulsedurationandcontrastarediscussed.

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  • 简介:磁铁矿(Fe3有不同尺寸和形状的O4)nanoparticles被热分解方法综合。二条途径,非注射一个壶和热注射的方法,被设计详细调查生长机制。nanoparticles的尺寸和形状被调整先锋集中和持续时间时间决定,这被发现,它能好在我们的合成系统基于LaMer模型由机制解释了。monodisperseFe3O4nanoparticles从5nm有一条吝啬的直径到16nm,和形状进化从对球形三角形、立方。磁性是尺寸依赖者,和Fe3在关于在房间温度和最大的浸透磁化的5nm展览superparamagnetic性质的小尺寸的O4nanoparticles来临到78emu/g,而Fe3O4nanoparticles当直径增加到大约16nm时,开发铁磁性的性质。

  • 标签: 纳米FE3O4 磁性纳米粒子 合成系统 单分散 FE3O4纳米粒子 可控
  • 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.

  • 标签: 纳米复合材料 锂离子电池 覆盆子 石墨 FE 性能
  • 简介:Room-temperaturetestwithhighpowerisanessentialstepbeforecouplersareinstalledonsuperconductingcavities.Anewroom-temperatureteststandisbeingdesignedatIMP.ThenewstandwillbeassembledwithaNC(normal-conducting)QWRcavity.Thepowerlossonthecavitywhencouplersareconditionedintraveling-wavemodehastobethoroughlyevaluated.Fig.1demonstratesthepowerflowintraveling-waveconditioningmode.Pe1andPe2representthepowerthatisextractedbycouplers.PfandPredenotetheforwardpowerandreflectedpower,respectively.

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  • 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.

  • 标签: curved crystal SPECTROMETER HARD X-RAY laser
  • 简介:Weexperimentallydemonstratea4×4nonblockingsiliconthermo-optic(TO)switchfabricconsistingofthreestagesoftunablegeneralizedMach–Zehnderinterferometers.All24routingstatesfornonblockingswitchingarecharacterized.Thedevice’sfootprintis4.6mm×1.0mm.Measurementsshowthattheworstcrosstalkofallswitchingstatesis-7.2dB.Theon-chipinsertionlossisintherangeof3.7–13.1dB.TheaverageTOswitchingpowerconsumptionis104.8mW.

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  • 简介:Afacilestep-by-stepapproachisdevelopedforsynthesizingthehigh-efficiencyandmagneticrecyclableFe_3O_4@SiO_2@Ag@Nitrepang-likenanocomposites.ThismethodinvolvescoatingFe_2O_3nanorodswithauniformsilicalayer,reductionin10%H_2/AratmospheretotransformtheFe_2O_3intomagneticFe_3O_4,andfinallydepositingAg@Nicore-shellnanoparticlesontheL-lysinemodifiedsurfaceofFe_3O_4@SiO_2nanorods.Thefabricatednanocompositesarefurthercharacterizedbyx-raydiffraction,transmissionelectronmicroscopy,scanningelectronmicroscope,Fouriertransforminfraredspectroscopy,andinductivelycoupledplasmamassspectroscopy.TheFe_3O_4@SiO_2@Ag@Nitrepang-likenanocompositesexhibitremarkablyhighercatalyticefficiencythanmonometallicFe_3O_4@SiO_2@AgnanocompositestowardthedegradationofRhodamineB(RhB)atroomtemperature,andmaintainsuperiorcatalyticactivityevenaftersixcycles.Inaddition,thesesamplescouldbeeasilyseparatedfromthecatalyticsystembyanexternalmagnetandreused,whichshowsgreatpotentialapplicationsintreatingwastewater.

  • 标签: 纳米复合材料 降解效率 催化剂 可回收 有机染料 海参
  • 简介:Wedemonstrateanintegratedall-fibermid-infrared(mid-IR)supercontinuum(SC)sourcegeneratedbya1.95μmmasteroscillatorpoweramplifiersystemandasingle-modeZBLAN(ZrF4–BaF2–LaF3–AlF3–NaF)fiber.Themaximumaverageoutputpoweris10.67Wwithspectralbandwidthcoveringfrom~1.9to4.1μm.Thesingle-modeZBLANfiberandsilicafiberarethermal-splicedtoenhancetherobustnessandpracticabilityofthesystem.Itis,tothebestofourknowledge,thefirsthigh-powerintegratedcompactedall-fibermid-IRSCsourcebasedonthermal-splicedsilicafiberandZBLANfiber.

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  • 简介:Vanadiumalloys(V-Cr-Tiseries)areimportantcandidatematerialsforblanketcomponentsoffusionreactorsduetotheirlowactivationandhighstrengthatelevatedtemperatures.Low-temperatureirradiationembrittlementdeterminestheoperationtemperaturelimitofVanadiumalloysfortheapplicationtostructuralmaterialsoffusionreactorsirradiationresponseofvanadiumalloysneedstobeclarifiedfortheirapplication.Inthepresentstudy,specimensoftwoalloys(V-4Cr-4TiandV-5Cr-5Ti)wereirradiatedwithenergeticHeionsandheavyionstounderstandhardeningofthealloysduetoheliumaccumulationandcascadedamageproduction.

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  • 简介:Multilayerblackphosphorus(BP)nanoplateletsofdifferentthicknesseswerepreparedbytheliquidphaseexfoliationmethodanddepositedontoyttriumaluminumgarnetsubstratestoformsaturableabsorbers(SAs).Thesewerecharacterizedwithrespecttotheirthickness-dependentsaturableabsorptionpropertiesat3μm.TheBP-SAswereemployedinapassivelyQ-switchedEr:Lu2O3laserat2.84μm.ByusingBPexfoliatedindifferentsolvents,stablepulsesasshortas359nsweregeneratedatanaverageoutputpowerofupto755mW.Therepetitionrateintheexperimentwas107kHz,correspondingtoapulseenergyof7.1μJ.TheseresultsprovethatBP-SAshaveagreatpotentialforopticalmodulationinthemid-infraredrange.

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  • 简介:Highlyefficientsheet-likeBiPO4/zeoliteandball-flower-likeBiPO4/zeolitehadbeensuccessfullysynthesizedbyastandardhydrothermalmethod.Theadditionofassistantreagentinthehydrothermalsystemispromisingtoobtainspecialmorphology.Theassistantreagent(EDTA)actsasagrowthmodifierofcrystal.Thepossibleformationmechanismsofsheet-likeBiPO4/zeoliteandball-flower-likeBiPO4/zeolitewereschematicallydiscussed.Adetailedstudyofsheet-likeBiPO4/zeoliteandball-flower-likeBiPO4/zeoliteimpactedonthephotodecolorationmethyleneblue(MB)solutionshowedthatthecompositehadahighlyreusableandstablepropertyforlong-runphotocatalyticapplication.

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  • 简介:TheGroupofEnergyMaterials(GEM)inIMPisengagedintheirradiationresponseofmaterialscandidatetoadvancednuclearenergysystems(GenIV,fusionreactors).Themajorprogressofresearchinourgroupin2016isintheirradiationhardening/embrittlementofoxide-dispersion-strengthened(ODS)ferriticsteelsandVanadiumalloys,andinthemechanismsunderlyingdamageproductioninsiliconcarbide(SiC)fibers.Abriefdescriptionisgivenasfollows.1.EffectoftheoxidenanoparticlesontheirradiationhardeningofODSferriticsteelsTheinfluenceofoxidenanoparticlesontheirradiationresistanceofODSferriticsteelsisacrucialissuefortheupgradeofODSsteels.

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  • 简介:Asafundamentalpropertyofnuclei,atomicmassesarewidelyusedinmanydomainsofscienceandengineering.Areliableatomicmasstablederivedfromtheexperimentaldata,wheretheatomicmassesandtherelevantexperi-mentalinformationcanbefoundconveniently,isinhighdemandbytheresearchcommunity.Tomeetthedemands,theAtomicMassEvaluation(AME)wasinitiatedin1950'sandaseriesofAMEmasstableshavebeenpublishedeversince.CurrentlytheAMEservestheresearchcommunitybyprovidingthemostreliableandcomprehensiveinformationrelatedtotheatomicmasses.ThenewatomicmassevaluationAME2016waspublishedintheMarchissueofChinesePhysicsCastwocom-plementarypapers[1;2].

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  • 简介:Themainworkoftheirradiationtechniquegroupfocusesonthefollowingtwoaspectsin2016:1.TechniquesupportWehavehadabout772.5hbeamtimefor39roundsofsingleeventeffect(SEE)tests,whichiscooperatingwithvariousinstitutes,universities,andcompanies.Thetestsarethebasicsafeguardforthespacecraftandsatellite.InordertoguaranteethetestefficiencyoftheTerminal5,themaintenanceandimprovementforthevacuum,thesampletransferandbeammonitorsystemhavebeenachieved.

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