简介：ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].

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简介：这属奥林匹克竞赛在芬兰的赫尔辛基举行。每个国家派5名学生参加。这届的规模出以往各届都大，共有来自37个国家的178名参赛者，而我也能够成为这次盛大竞赛的参加者之一！

简介：TheprogressofresearchgoingoninGroupofEnergyMaterials(GEM),MaterialResearchCenter,in2014isinthefollowingthreeaspects.1.FacilitydevelopmentInordertopushforwardourstudyonfusionreactormaterials,weupgradedtheirradiationterminal(128#)ofthesectorfocusedcyclotron(SFC)atHIRFL,bydevelopinganewspecimenstagespecificforirradiationwithlow-fluencescatteredions.Sofartheterminaliscapableofirradiationtobothverylowfluences(106ions/cm2)andveryhighfluences(typically1016ions/cm2)forvariousmaterials.SpecimentemperaturecanbereadilycontrolledusingtheL-N2coolingstageorthethehigh-Tstage(upto600oC).Ourrecentinvestigationwithtransmissionelectronmicroscopy(TEM)ofthedefectsproducedbyhigh-energyNeionsinsteelspecimensprovidesaclearevidencethatdefectswereproduceduniformlyalongthedepthinthespecimen,indicatingthattheenergydegraderoftheterminalworkseffectivelytodispersetheionenergyinawiderange.AphotooftheterminaltogetherwithaSRIMestimateofdepthprofilesofdamageinan8%Crreducedactivationferritic/martensiticsteel(RAFMS)isshowninFig.1.

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简介：IntroductionIn2O3·Snfilmshavehightransparency（>95％）withinthevisiblespectralregion,lowresistivity(10-2—10-4ohm·cm)atroomtemperatureandsuperiorthermalstability.Thesefilmshavebeenappliedtosolarcells,electronicsandphotoelectronicsfields.Inrecentyears,organometallic-CVDmethodhasemergedasasuccessfulalternatetothephysicalmethodsandgeneralCVDforthegrowthofthesefilms.TheMO-CVDtech-

简介：本标准规定了亚磷酸三（2，4-二叔丁基苯基）酯（简称抗氧剂168）的要求，试验方法，检验规则，标志、包装、运输及贮存。

简介：1范围本标准规定了四[β-二叔丁基-4-羟基苯基）丙酸]季戊四醇酯（简称抗氧剂1010）的要求，试验方法，检验规则，标志、包装、运输及贮存。

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简介：Theresearchacceleratorsaregrowinginenergyandpowerwhichinducesanincreaseoftheprojectcosts(Fig.1).TheRFcavitiesandpowersupplymainlycontributethecostofthesuperconductinglinac,whichisacompetitivetechnologyforhighpowermachine.AcodewithoptimizationalgorithmisdevelopedtooptimizethebetavalueofSCcavityfamilyandtransitionenergytoincreasetheTTFvalueofthewholelinac.

简介：Duringsolareclipse,thelunarshadowmovesthroughtheearth‘satmospherewithsupersonicspeed.ChimonasandHinesdeemedthattheshockwavesproducedbycoolingofatmospherewouldinducegravitywaves,andbothTIDsandatmosphericpressurechangescanbedetectedintheionosphereandonthegroundrespectively.AlthoughtheIGWsignalsfromsolareclipseareusuallyquiteweak,theycanstillbedetected.Thepressurechangesongroundleveloccurneartheregionofeclipse,butcanbedetectedevenfarbeyondthepathofeclipse.ThisarticleisthefirstonetoreportresultsofdetectingpressurewavescausedbysolareclipseinChina.Druingthe23rdSeptember1987annularsolareclipse,IGWshavebeendetectedandrecordedatinfrasoundobservatoriesin(?)r(?)mqi,Taiyuan,XuzhouandSuzhou,whicharesituatedwithinthepathofannulareclipse,aswellasinBeijingandGuiyang,whicharesituatedontheoppositesidesofthispath.Thesignalsaredetectedbymicrobarometersofcondensermicrophonetype.Afteran

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简介：SpokecavitieshavebeendevelopedandhaveapparentadvantagesforhighcurrentprotonacceleratorbasedonFig.1(coloronline)Theelectromagneticfielddistribution.superconductivityatlowandmediumenergyregion.Astheresearchandthetechnicalreserve,InstituteofModernPhysics(IMP)hasstartedtheR&Dprogramofadoublespokecavity(operatingfrequency325MHz,0=0.52),withintheframeworkofChinaAcceleratorDrivenSystem(C-ADS)project.TheRFdesignandmechanicalstructuredesignhavebeenfinished,andtwoprototypecavitiesweremanufacturedinHarbin.

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简介：<正>海南省2013年中考数学第23题是以正方形为基本图形,综合三角形、四边形与图形变换等主干知识的一道"压轴题",是一道极具"灵气"的题目,注重对数学思想方法与学生探究能力的考查.一、试题赏析海南省2013年初中毕业生学业考试数学科试题第23题为:

简介：Abstract.Usingthemethodofundeterminedfunction,asetof12parameterrectangularp|atedementwithdoub[esetparameterandgeometrysymmetryisconstructed.TheirconsistencyerrorareO(h2),oneorderhigherthantheusua[12parameterrectangu|arp[ateelements.