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37 个结果
  • 简介:Wereportonaone-stageerbium-dopedfibreamplifiedspontaneousemission(ASE)sourcewith80nmbandwidthand13.5dBmoutputpower.thebroadbandwidtherbiumASEsourcewasrealizedinanerbium-dopedfibrewith37mlengthbya1480nmlaserdiodeanda980nmlaserdiodeasforwardandbackwardpumpsources,respectively.Thetotalpumppowerisonly95.7mW.

  • 标签: 宽带光源 铒掺杂 自发发射光源 激光器
  • 简介:Variousagriculturalcropresiduesincludingcornstover,corncob,andsorghumstalkwithamoisturecontentof75wt%weresubjectedtoalongpretreatment(12-60h)withsupercriticalCO2(scCO2),atlowtemperature(50-80℃)andapressureof17.5-25.0Mpa.Thesugaryieldsfromtheenzymatichydrolysis(EH)ofthepretreatedsampleswereasmuchasthree-tofourfoldgreaterthanthoseaffordedbytherawmaterials.However,whenpretreatmentwasconductedwithinashorttime(e.g.0.5h),aspreviouslyreportedintheliterature,onlyaslightincreaseintheEHsugaryieldswasobserved.TheproposedscCO2pretreatmentmechanismdemonstratedtheroleofmoistureinthesystem.Wetting,softening,andswellingwereobservedtomainlyaffectthelignocellulosewhenasuitableamountofwaterwasadded.Finally,thesampleswereanalysedbyX-raydiffractionandscanningelectronmicroscopy,beforeandafterpretreatment,toinvestigatethechangesinthemicroscopicstructureofthebiomass.

  • 标签: LIGNOCELLULOSE scCO2 PRETREATMENT ENZYMATIC HYDROLYSIS SUGAR
  • 简介:DMX-I型电子模拟式手弧焊工训练器为国内首创的机电一体化的初级焊工训练器、本文对训练器商品化的前景,训练器的功能的完善等方面的问题进行了讨论.

  • 标签: 焊工训练器 商品化
  • 简介:为了在柴油的核心区域调查微滴尺寸的分发,喷洒,微滴尺寸的即时测量被先进激光2焦点速度计(L2F)进行。L2F的微规模的探查由二foci组成,在他们之间的距离是36μm。测试的嘴有0.2公里直径单个洞。注射压力,针电梯,和曲柄角度的大小被L2F在位置与测量同步从嘴出口的10公里downstream。比在在针下面的离开轴区域,完整的电梯调节并且微滴尺寸的空间分发改变速度集合,水花轴附近的微滴才大。在水花核心区域的微滴尺寸的概率密度分发能在大多数注射时期被适合到Nukiyama-Tanasawa分发,这被发现。

  • 标签: 飞沫瓦解 光学特征 激光聚集 速度计
  • 简介:对将运行于日-地L1点的太阳观测器进行了热设计,重点论述了日-地L1点的轨道外热流计算和Lymanα日冕仪(LACI)反射镜M2光阱、Lymanα日冕成像仪(LADI)滤光片组件、CCD组件、电箱、观测器主体等部分的热设计方案。通过在探测器对日面设置集热板,将观测器的主动加热功耗降低了73%;选用预埋热管的设计方案解决了对日定向观测导致的框架温差问题。仿真分析结果表明,在对日高温工作、对日低温工作、低温存储、轨道转移等4个极端工况下,观测器各组件温度均满足指标要求。该热设计方案以较低的加热功耗,解决了太阳观测器在轨工作阶段的散热、轨道转移阶段的保温等问题,满足CCD焦面工作温度<-50℃的要求。

  • 标签: 热设计 Lymanα日冕仪 Lymanα日冕成像仪 太阳观测
  • 简介:Thermoelectricityisatherrnorelatedpropertythatisofgreatimportanceinsingle-moleculejunctions.Theelectricalconductance(σ),electron-derivedthermalconductance(kel)andSeebeckcoefficient(S)ofBgo-basedsingle-moleculejunctionsareinvestigatedbyusingdensityfunctionaltheoryincombinationwithnon-equilibriumGreen'sfunction.Whenthedistancebetweentheleft/rightelectrodesis11.4A,therelationshipbetweenσandkelobeystheWiedemann-FranzlawverywellbecauseofthestronghybridizationbetweenB80molecularorbitalsandthesurfacestatesofAuelectrodes.Furthermore,thecalculatedLorenznumberisclosetothefamousvalueinmetalordegeneratesemiconductors.Inaddition,Sisonly—19.09μV/Kat300K,thusleadingtothesmallerelectron'sthermoelectriefigureofmerit(ZeiT=S^2σT/Kel).Interestingly,thestrainandchemicalpotentialcanmodulateB80-basedsingle-moleculejunctionsfromn-typetop-typewhenthecompressivestrainreaches—0.6Aorthechemicalpotentialshiftsto—0.16eV.ThismightbeattributedthatSreflectstheasymmetryintheelectricalconductancewithrespecttothechemicalpotentialandisproportionaltotheslopesofthetransmissionspectrum.

  • 标签: THERMOELECTRICITY SINGLE-MOLECULE JUNCTION NON-EQUILIBRIUM Green FUNCTION
  • 简介:Whenmeasurementsareperformedinhighspeed,small-scalecompressors,theuseofcurvedglasswindowsisrequiredinordertoavoidanymismatchbetweenthemeasurementwindowandthecasing.However,theglasscurvatureleadstoopticaldistortions,whichhinderacceptablemeasurementsandcanevenpreventtheacquisitionofanydata.Thus,anoriginalopticalassembly,whichconsistsininsertingasimpleandinexpensivecorrectivewindowbetweenthefrontallensoftheanemometerandtheshroudwindow,isproposed.Thewayofdeterminingthegeometriccharacteristicsandthepositionofthiscorrectivewindow,whichrestoresveryacceptablefoci,ispresentedinthepaper.Thereliabilityofthiscorrectiveopticalassemblyishighlightedbycomparativemeasurementsinatestcase.Usingsuchanopticalsetting,L2Fmeasurementswererealisedalongasection,downstreamoftheinletguidevane(IGV)ofatransoniccompressorstage.Thespatialresolutionleadstoagooddescriptionoftheinteractionofthewakewiththeobliqueshockemanatingfromtheleadingedgeoftherotor.Aphenomenologicalstudyofthewake/shockinteractionwithachangeofframeisrealisedusingthestreamwiseequationofthetransportofvorticity.

  • 标签: 空气压缩机 风速测量 曲线窗形
  • 简介:ThedetailedmicrostructuresofNi80Fe20/Fe50Mn50superlatticeshavebeencharacterizedusingbothx-raydiffractiontechniquesandtransmissionelectronmicroscopy.Theobrivouslayeredstructure,typicalcolumnstructureandtwinswhichexistinNi80Fe20/Fe50Mn50superlatticeswereobservedthroughperformingtransmissionmicroscopy.Bycombiningthetechniqueoflowanglex-rayreflectivity(specularandoff-specularscans)withtheanomalousscatteringeffectandhigh-anglex-raydiffraction(usingconventionalx-ray),wequantitativelyanalysedthemicrostructuralvariationasafunctionofannealingtemperature.Itisfoundthatthelateralcorrelationlength,the(111)peakintensityofthesuperlatticesandtheaveragemultilayercoherencelengthallincreasewithariseinannealingtemperatureannealingcandecreasetherootmean-squareroughnessattheinterfacesofNi80Fe20/Fe50Mn50superlattices.theobtainedmicrostructuralknowledgewillbehelpfulinunderstandingthemagneticpropertiesoftheni80Fe20/Fe50Mn50exchangebiassystem.

  • 标签: Ni80Fe20/Fe50Mn50超晶格 X射线衍射分析 微观结构 电子输运
  • 简介:在“强光一号”加速器上,对LM7805型电源芯片和EE80C196KC20型单片机进行了脉冲γ辐照效应实验研究,获得了单片机的闩锁阈值,并得到了单片机和电源芯片的扰动时间随剂量率的变化规律,从实验上证实了电源芯片对单片机脉冲γ辐照闩锁效应的抑制作用.

  • 标签: 脉冲γ辐照 单片机系统 闩锁 瞬时扰动
  • 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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