简介：利用三维电磁场时域有限差分法,研究了n型硅片对0.3～0.4THz高功率脉冲的响应.模拟计算了波导内电场分布、电压驻波比及硅块内平均电场,给出了硅块几何尺寸和电阻率对上述物理量的影响规律.通过调整硅块的长、宽、高及电阻率,最后给出了一种可用于该频段高功率太赫兹脉冲功率测量的探测器物理模型,其灵敏度约为0.509kW-1,幅度波动不超过±14％,电压驻波比不大于1.34.

简介：加工中心换刀功能的设计及调试是实现加工中心整体功能的重要部分。针对斗笠式刀库，应用固定选刀方法，改进刀库初始化的硬件，开发相关NC换刀固定循环程序和PLC软件，配合z轴运动、主轴准停、松拉刀气缸、刀库进退气缸等执行部件，实现了加工中心的换刀功能。

简介：Atemperature-inducedspinreorientationtransitionbetweenГ4(Gx,Ay,Fz)andГ2(Fx,Cy,Gz)hasbeenstudiedinthefamilyofEr1–xYxFeO3(x=0,0.25,0.5,0.75,1)singlecrystals.BydopingnonmagneticY3+,wetunedthespinreorientationtemperaturetolowtemperaturewithincreasingx.Moreover,thetypicalcompensationpointandspinfliptransitionofErFeO3alsodecreaseswithdoping,anddisappearsabovex=0.75.WealsoreporttheRietveldrefinementsandRamanspectroscopyofEr1–xYxFeO3,wheresomeRamanpeaksareshiftedtolowfrequencywithincreasingdoping.Ourresultsshedlightontheunderstandingoftheinteractionbetweentwomagneticsub-latticesofrareearth(R3+)andiron(Fe3+)ions,andwillalsocontributetothematerialsdesignandpotentialapplications.

简介：Veryrecently,theBelleandBESIIIexperimentsobservedanewcharmonium-likestateX(3823),whichisagoodcandidatefortheD-wavecharmonium(13D2).BecausetheX(3823)isjustneartheDˉDthreshold,thedecayX(3823)!J=+??canbeagoldenchanneltotestthesignificanceofcoupled-channeleffects.Inthiswork[1],thisdecayisconsideredincludingboththehidden-charmdipionandtheusualquantumchromodynamicsmultipoleexpansion(QCDME)contributions.

简介：Recently,theL-modetoH-mode(L-H)transitionintokamakplasmaconfinementwasfoundtoberelatedtothepresenceofthepoloidalflowshearneartheplasmaedge.Animportantmechanismistheionorbitlosscausedbyinteractionwiththelimiter.AcomplementaryexplanationisthegenerationofpoloidalflowsbyplasmafluctuationsviatheReynoldsstressandthepoloidalspin-upofplasmasfrompoloidalasymmetryofparticleandmomentumsources.

简介：Supersonicmolecularbeaminjection(SMBI)wasfirstproposedanddemonstratedontheHL-1tokamak,wassuccessfullydevelopedandusedontheHL-1Mtokamak,andwasthenappliedontheHT-7superconductingtokamak,theToreSupratokamakandtheWT-ASstellarator.Withthenew

简介：Basedontheextendedmappingdeformationmethodandsymboliccomputation,manyexacttravellingwavesolutionsarefoundforthe(3+1)-dimensionalJMequationandthe(3+1)-dimensionalKPequation.Theobtainedsolutionsincludesolitarysolution,periodicwavesolution,rationaltravellingwavesolution,andJacobianandWeierstrassfunctionsolution,etc.

简介：本文介绍了对ＭＪ—ｌ型静电场实验仪的一种改进方法．改进后的仪器能直接记录电位线。

简介：Withthehelpofanextendedmappingapproach,anewtypeofvariableseparationexcitationwiththreearbitraryfunctionsofthe(2+1)-dimensionaldispersivelong-waterwavesystem(DLW)isderived.Basedonthederivedvariableseparationexcitation,abundantnon-propagatingsolitonssuchasdromion,ring,peakon,andcompactonetc.arerevealedbyselectingappropriatefunctionsinthispaper.

简介：TheextendedRiccatimappingapproachisfurtherimprovedbygeneralizedRiccatiequation,andcombineitwithvariableseparationmethod,abundantnewexactcomplexsolutionsforthe(2+1)-dimensionalmodifieddispersivewater-wave(MDWW)systemareobtained.Basedonaderivedperiodicsolitarywavesolutionandarationalsolution,westudyatypeofphenomenonofcomplexwave.

简介：π-/π+ratiowasfoundtobeasensitiveprobetothehigh-densitybehaviorofthesymmetryenergybyusingseveraltransportmodels.However,asshowninFig.1,atbeamenergiesbelowthepionproductionthreshold,theeffectsofin-mediumnucleon-nucleonscatteringcrosssection(whichisstillcontroversial)stronglyaffectthevalueofπ??/π+ratio[1].Itisthusnecessarytodoacomparativestudyoftheeffectsofthein-mediumNNcrosssectionandtheeffectsofthesymmetryenergyonpionproductioninheavy-ioncollisionsatlowerbeamenergies.

简介：Basedonthedensity-functionaltheory,thispaperstudiesthegeometricandmagneticpropertiesofTinO(n=1-9)clusters.TheresultinggeometriesshowthattheoxygenatomremainsonthesurfaceofclustersanddoesnotchangethegeometryofTinsignificantly.Thebindingenergy,second-orderenergydifferenceswiththesizeofclustersshowthatTi7Oclusterisendowedwithspecialstability.ThestabilityofTinOclustersisvalidatedbytherecenttime-of-flightmassspectra.ThetotalmagneticmomentsforTinOclusterswithn=1-4,8-9areconstantwith2anddroptozeroatn=5-7.Thelocalmagneticmomentandchargepartitionofeachatom,andthedensityofstatesarediscussed.ThemagneticmomentoftheTinOisclearlydominatedbythelocalized3delectronsofTiatomswhiletheoxygenatomcontributesaverysmallamountofspininTinOclusters.

简介：

简介：对称一(2+1)维的浅水波浪系统，最新通过使用分析力学的变化原则被构造，在这篇论文被研究。谎言对称和相应减小借助于古典谎言组途径被获得。(1+1)维的排水量当特殊对称参数被选择时，浅水波浪方程能从减小被导出。

简介：UsingthestandardtruncatedPainlevexpansion,theresidualsymmetryofthe(2+1)-dimensionalmodifieddispersivewater-wavesystemislocalizedintheproperlyprolongedsystemwiththeLiepointsymmetryvector.Somedifferenttransformationinvariancesarederivedbyutilizingtheobtainedsymmetries.ThesymmetriesofthesystemarealsoderivedthroughtheClarkson-Kruskaldirectmethod,andseveraltypesofexplicitreductionsolutionsrelatetothetrigonometricorthehyperbolicfunctionsareobtained.Finally,somespecialsolitonsaredepictedfromoneofthesolutions.

简介：Westudythesymmetriesofa(2+1)-dimensionalgeneralizedBroer-KaupsystembymeansoftheclassicalLiegrouptheory.Thecorrespondinggroupalgebraisconstructed.Basedonthesymmetries,severaltypesofsimilaritysolutionsareobtained.

简介：Usingafurthermodifiedextendedtanh-functionmethod,richnewfamiliesoftheexactsolutionsforthe(2+1)-dimensionalBroer-Kaup(BK)system,comprisingthenon-travelingwaveandcoefficientfunctions'soliton-likesolutions,singularsoliton-likesolutions,periodicformsolutions,areobtained.

简介：ResourcesonacomputationalGridaregeographicallyistributed,heterogeneousinnature,ownedbydifferentindividualsororganizationswiththeirownschedulingpolicies,havedifferentaccesscostmodelswithdynamicallyvaryingloadsandavailabilityconditions.Thismakertraditionalapproachestoworkloadmanagement,loadbalancingandschedulinginappropriate.Thefirstworkpackage(WP1)oftheEU-fundedDataGridprojectisadddressingtheissueofoptimzingthedistributionofjobsontoGridresourcesbasedonaknowledgeofthestatusandcharacteristicsoftheseresourcesthatisnecessarilyout-of-date(collectedinafiniteamonutoftimeataverylooselycoupledsite).WedescribetheDataGridapproachinintegratingexistingsoftwarecomponents(fromCondor,GGlobus,etc.)tobuildaGridResourceBroker,andtheearlyeffortstodefineaworkableschedulingstrategy.

简介：研究了角动量守恒定律的教学问题,研制成功一种新的便携式角动量守恒定律的实验装置,该装置具有制作简单,实验现象清晰直观,重复性好的特点.

简介：近年来,最高能量在250MeV左右的质子辐照装置因在质子治疗、质子辐照效应研究等领域的应用前景而受到广泛关注。清华大学目前正在计划建设一个此类质子辐照装置,其最高能量可达230MeV,一个工作周期至少输出2×10^11个质子,且引出的束流是准连续的。该辐照装置的核心部分是一个能够将质子由7MeV加速到230MeV的同步质子加速器。简要介绍了该同步加速器的关键技术及设计结果,包括为实现高效累积足够流强而使用的剥离注入技术、为提升加速效率而使用的纵向绝热俘获技术以及为实现束流缓慢引出而使用的三阶共振引出技术。