简介:JUNA(JinpingUndergroundlaboratoryforNuclearAstrophysics)isplaningtomeasurethe13C(α,n)16OandsomeotherimportantreactionsatorclosetostellarenergiesusingintenseheliumbeamoutofanECRdrivenacceleratorinJinpingUndergroundlaboratory[1].Deuteriumimpurityinionsourcewillproducessignificantamountofneutrons,limitingthebackgroundlevel.Tocontrolthedeteriumimpurity,wehavedevelopedamethodtomeasurethedeuteriumimpuritywithinHeliumbeamusingthed(d,p)treaction.
简介:Asafundamentalpropertyofnuclei,atomicmassesarewidelyusedinmanydomainsofscienceandengineering.Areliableatomicmasstablederivedfromtheexperimentaldata,wheretheatomicmassesandtherelevantexperi-mentalinformationcanbefoundconveniently,isinhighdemandbytheresearchcommunity.Tomeetthedemands,theAtomicMassEvaluation(AME)wasinitiatedin1950'sandaseriesofAMEmasstableshavebeenpublishedeversince.CurrentlytheAMEservestheresearchcommunitybyprovidingthemostreliableandcomprehensiveinformationrelatedtotheatomicmasses.ThenewatomicmassevaluationAME2016waspublishedintheMarchissueofChinesePhysicsCastwocom-plementarypapers[1;2].
简介:134Csabranchingpointins-processpathwhichisshowninFig.1.Thebranchingratioisdefinedasfβ=λβ/(λβ+λn).Itcouldbededucedfromtheabundanceof134Baand136Basince136Bagoesthroughbothdecayandneutroncaptureof134Cswhile134Baonlyexperiencesdecaychannel[1].Duetoboth134Baand134Baarepures-processnuclei,thisbranchingpointisagoodapproachtodeterminethes-processparameters.Withtemperaturedependentβ-decayrateof134Cs,thetemperatureofs-processcouldbededuced.
简介:Tomeettherequirementoflong-timeacquisitionwithoutinterruptionsfortheplannednucleardecayexperimentsatCSRe,anewdataacquisitionsystemhasbeensuccessfullydevelopedin2016.DuringthebeamtimeinDec.2016,ournewsystemhasbeenrunningstablywithoutanyproblemsandcontinuouslyacquiringhundredsofdatawithoutanybreaks.Thewholesystemisbasedonaspectrumanalyzer(R&SFSVR7)andanIQrecorder(R&SIQR100).BothofthemareconnectedtoaserverviaEthernet.Thespectrumanalyzeracquiresthetime-domaininformationinthefrequencyrangeofinterestfromtheSchottkyresonator.TheIQrecordercollectstheinformationfromtheanalyzerandpacksitintodata.Oncethedatahavebeenentirelytransferredtotheserver,itwillimmediatelyberemovedfromIQrecorder.Thehigh-volumesolid-statedrive(1TB)ofIQrecorderallowsforavirtuallyunlimitedsizeofacquiredlestobestoredinpractice.Besides,inordertobypasstheunreliabletriggersystemofIQrecorder,webuiltanindependenttriggersystemwithamicrocontroller(ArduinoYun)totranslatetheTTLsignaltonetworkcommands.
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:WeinvestigatethenonlinearSchrdingerequationiut+△u+|u|p-1u=0with1+4/N
2)(whenN=1,2,1+4/N
2>||Q||(1-sc)/sc|▽Q||2,theneitheru(t)blowsupinfiniteforwardtimeoru(t)existsgloballyforpositivetimeandthereexistsatimesequencetn→+∞suchthat||▽u(tn)||2→+∞.HereQisthegroundstatesolutionof—(1—sc)Q+△Q+|Q|p-1Q=0.Asimilarresultholdsfornegativetime.Thisextendtheresultofthe3DcubicSchr(o|¨)dingerequationobtainedbyHolmertothegeneralmass-supercriticalandenergy-subcriticalcase.
简介:Tungstendisulfide(WS2)isatypeofanisotropic-layeredcompoundandhasbroadbandsaturableabsorptionfeaturesassaturableabsorbers(SAs).WithWS2-basedSAs,darksolitonsinerbium-dopedfiber(EDF)lasersarefirstobtained.Forthegenerateddarksolitons,thecenterwavelengthismeasuredtobe1530nm,andtherepetitionrateisabout116.5MHz.Aseriesofopticalspectraisexhibited.Theelectricalsignal-to-noiseratioisbetterthan94dB.ResultsinthispaperdemonstratethatWS2-basedSAsarethepromisingSAsforgeneratingdarksolitonsinEDFlasers.
简介:基于刚性配体2-(4-噻唑基)苯并咪唑和二价金属铜离子在水热条件下成功地合成了2个Keggin型多酸化合物[CuⅡ(L1)2(H2O)]2[SiW12O40](1)和[(L1)4(L2)2(H3PMo12O40)2]·5H2O(2)(L1=2-(4-噻唑基)苯并咪唑,L2=苯并咪唑).通过单晶X-射线、红外光谱和元素分析对化合物1和2进行了表征.在化合物1中,存在2个独立的结构单元:Keggin型多酸和蝴蝶状的络合物阳离子[Cu(L1)2(H2O)]2+.化合物2为含有混合配体的超分子结构,由Keggin型多酸、4个游离的L1和2个L2配体组成.此外,研究了化合物1和2的电化学和光催化性能.
简介:Birefringenceattractsincreasingattentionduetoitsextensiveapplicationsintheimagingspectrometer,laserdevicesandopticalcomponents.Stimulatedbythediscoveryofthegiantbirefringence(GBF)inLaOBiS_2andAFBiS2,weexploreitsoriginbycheckingthreecompoundswithandwithouttheBiS_2layer:Bi_2OS_2(i.e.,BiOBiS_2),Bi_2O_2SandLaOAlS_2.ItisdemonstratedthatGBFappearsonlyinthecompoundswiththeBiS_2layerandisfurthermoreconfirmedinMOBiS_2(M=AI,Ga,InandSc)compounds.Theresultisusefulfordiscovering/developingnew-typebirefringentcrystalorevenmultifunctionalmaterials.
简介:二轨道的哈伯德模型被在真实空间和动量空间使用Hartree-Fock近似数字地学习,并且碱金属的地面状态性质熨硒化物半导体的KFe1.5Se2被调查。有,顺序被发现的stripetypeantiferromagnetic(AFM)的一份菱形类型Fe空缺订单在散布实验的中子被观察[J.赵,等,Phys。加快。Lett。109,267003(2012)]。跳跃参数被在真实空间适合试验性地观察的条纹AFM阶段获得。这些跳跃参数然后被用来在动量空格学习半导体的地面状态性质。是有大所在地的库仑排斥U的一个强烈相关的系统被发现,类似于莫特·阿夫姆绝缘体铜氧化物超导体的父母混合物。我们也发现在dxz和dyzorbitals的电子职业数字和磁化同时变得不同,显示轨道的订什么时候U>Uc(3.4eV)。这些结果暗示在二orbitals之间的旋转对称被轨道的订打破并且因此驾驶磁性的联合的强壮的anisotropy被实验观察了并且在这混合物的条纹类型AFM顺序可以被和观察大anisotropy的轨道的订引起。
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简介:AnefficientprocessfortheconversionofdimethyloxalateintoethyleneglycolwithhighselectivityandhighyieldoverCu2Owasinvestigated.InsituformedCuasatruecatalyticallyactivespeciesshowedagoodcatalyticperformanceforDMOconversiontoproduceEGin95%yield.
简介:Atacertainhightemperature,thiscyclewillbedominantandendtherp-processtoheavierregion[2].Itprovidesanuppertemperaturelimitforrp-processalongtheprotondriplinetoproducenuclidesbeyondA=84,includingthelightpnuclidesof92;94Mo,96;94Ru.TheexistenceofZr-Nbcycleisanimportantquestioninrp-process[2].α-separationenergy(Sα)of84Moplaysanimportantroleintheformationofthiscycle.Astrongenhancementof83Nb(p,α)reactionrateisduetoaverylowSαof84Mo[1].