学科分类
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92 个结果
  • 简介:开展多轴振动台的随机振动控制,以6自由度液压振动台(简称振动台)为典型受控对象,对设计的多输入多输出(简称MIMO)随机振动控制算法,进行了算法研究与验证。在研究中,考虑振动台为非完全解耦系统。

  • 标签: 随机振动控制 液压振动台 6自由度 MIMO 仿真 多输入多输出
  • 简介:ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].

  • 标签: FIRST DIRECT MEASUREMENT
  • 简介:Radiotherapyisacommontreatmentmodalityforheadandneckcancers,nasopharyngealcancers,primarybraintumorsandbrainmetastases.Alargenumberofpatientsintheworldwithprimaryormetastaticbraintumorswillrequirelargevolumeorwholebrainirradiationeveryyear.However,therapeuticirradiationnotonlykillstumorcells,butalsoinjuresnormalbraintissue,whichiscommonlyassociatedwithsignificantfunctionalmorbidityanddecreasedqualityoflifeinpatientstreatedwithbrainradiotherapy[1].

  • 标签: Protective Effects Hydroxysaffor
  • 简介:Theabinitiogeneralizedgradientapproximation(GGA)+Ustudyofmultiferroic(La0.5Bi0.5)2FeCrO6inpnmastructureandferri-magneticorder,includingHubbardcorrections(U-4.1eV)fortransitionmetal/rareearthd-electronswith20atomscell,showsoptimumlocalmagneticmomentsof(Cr^3+,Fe^3+)equalto(-2.56,4.14)#Bandanidealspin-downbandgapof1.54eV.Tuned-bandgapLa-substituteddoubleoxideperovskitesBFCOshouldexhibitenhancedvisible-lightabsorptionandcarriermobility,thuscouldbeconvenientlightabsorbersandthenefficientalternativestowide-gapchalcopyriteabsorber-basedsolarcellsfailingtoachievehighestpowerconversionefficiencies,andevencompetewiththeirmetal-organichalideperovskitescounterparts.

  • 标签: OPTIMAL Bandgap Double Perovskite La-Substituted Bi2FeCrO6
  • 简介:H+-restackednanosheetsandnanoscrollspeeledfromK4Nb6O17displaydifferentstructuresandsurfacecharacters.Thetworestackedsampleswithincreasedsurfaceareashaveanamazingvisible-lightresponseforthephotodegradationofdyes,whichissuperiortocommercialTiO2(P25)andNb2O5.Bycomparison,H+/nanosheetshavearelativelyfasterphotodegradationrateoriginatedfromlargeandsmoothbasalplane.Theworkrevealsthatdyeadsorbedontheunfoldednanosheetscaneffectivelyharvestsunlight.Duetofacilepreparation,low-costandhighphotocatalyticefficiency,H+/nanosheetsandH+/nanoscrollsmightbeusedforthevisiblelight-drivendegradationoforganicdyesasasubstituteforTiO2inindustry.

  • 标签: 可见光降解 染料吸附 纳米 堆栈 压入 可见光响应
  • 简介:Wehavereportedthemassmeasurementsofneutron-deficientnuclides79Y,81;82Zr,83;84Nbinthisyear’sAnnualReport.However,fortheN=ZnuclidesclosetoA=80,theyieldismuchlowerandeveniftheycanbeproduced,thereisstillgreatdifficulttoidentifythembecauseoftheirquitesimilarmass-to-chargeratioandrevolutiontimes.However,theirmassareextremelyimportantforrapidprotoncaptureprocess,forexample,80Zrand84Moarewaitingpointsofrp-process.Theirmassescangreatlyeffectthereactionflowofprotoncaptureonthemandthentheabundanceoftheheaviernuclides.Inaddition,theseparationenergyof84Mo(determinedbythemassof80Zrand84Mo)hasastrongimpactonthe83Nb(p,α)reactionrateandplaysakeyroleintheformationofZr-NbFig.

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  • 简介:合成了一维绳梯链状双金属化合物[Ni(en)2]3[Fe(CN)6]2·2H2O,并对其变温穆斯堡尔谱进行了研究,结果表明该分子磁体中铁的电子态为低自旋Fe3+,而大的四极分裂值(QS)表明此化合物的[Fe(CN)6]3-单元对称结构发生了形变,低温时出现的磁弛豫谱,给出了在该温度点附近出现铁磁耦合相互作用的信息。

  • 标签: 穆斯堡尔谱 磁弛豫 形变