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500 个结果
  • 简介:Na离子电池由于他们的低费用和自然许多Na资源为大规模精力存储系统被认为一种有希望的选择到Li离子电池。大努力全球正在做为Na离子电池开发高效的电极材料,它为Na离子电池是批评的。这评论基于Na存储机制为Na离子电池提供阳极材料的全面概述:基于插入的材料,基于合金的材料,基于变换的材料和器官的composites。并且我们总结那些阳极材料的Na存储机制并且讨论他们的失败机制。而且,与那些阳极联系的问题和挑战被指出,并且可行策略为设计高效的阳极材料被建议。根据研究的当前的状态,尽管实质的进步被获得了,为为Na离子电池的合适的阳极材料的搜索仍然是挑战性的。不过,我们相信高效的Na离子电池在不久的将来将为在大规模精力存储系统的实际应用程序是有希望的。

  • 标签: 阳极材料 电池开发 NA 离子 存储机制 存储系统
  • 简介:与大约2个小时的时期,高周波的摆动被把小浪分析用于首先识别详细地绕热带气旋(TC)的眼睛和eyewall观察了风速度。台风Hagupit(2008)的模型模拟的分析证明摆动也在eyewall附近发生在TC紧张,垂直运动,集中活动和空气密度。在这些变量的摆动的序列跟随某个顺序。

  • 标签: 高频振荡 热带气旋 识别 小波分析 模型仿真 垂直运动
  • 简介:Theexperimentalstudyofultra-wideband(UWB)technology,itsgenerationandon-linemeasurementarepresented.AnexperimentalrepetitiveUWBsystemisdesigned,manufactured,andtested.High-pressuresparkgapswitchanditscomponents,aswellasoilsparkgapswitcharestudiedexperimentallyonthesystem.Experimentalresultsindicatethatthesystemoperatesata200ppsrepetitiveratewithastableperformance.100MWpeakpowerUWBpulsesareobtainedonthesystem.Fast-timeresponsecapacitivedividerisdesignedandfabricated,allowingforanaccuratemeasurementofthehighpowerUWBsignal.ThemainissuesrelatedtothedesignoftheswitchandtheUWBsignalonlinemeasurementarediscussed.

  • 标签: 高压开关 超宽带 高能微波 UWB
  • 简介:Low-carbonbecomesahigh-frequencyandfashionablewordwhichgetsthegreatestconcernintheworld.Low-carbonreferstoaminimaloutputofgreenhousegasemissionsintothebiosphere,specificallyreferstothegreenhousegascarbondioxide.Toreduceenergyconsumptionofautomobile,moreandmorehighstrengthsteelsareusedbyvehiclecompanies.Tomeettherequestofvehiclecompanies,varioushighstrengthsteelsaredevelopedinsteelcompaniesallovertheworld.Ansteelcanprovide,ultra-lowcarbonbakehardening(BH)steels,dualphase(DP)steelsandtransformation-inducedplasticity(TRIP)steelswiththegradesofunder780MPa,uptonow.AHSSsteelshavemuchdifferentcomposition,microstructureandstrenghtthanconventionalvehiclesteels,sotherearesometroubleinproducingincoldrollingmills,forexample,difficulttojoin,poorthicknessandflatness,accuratetemperatureandvelocitycontrolandsoon.Toreducetheopportunityofstripbreakage,wehavedonemanyweldingexperimentsandspecialresearch.Now,DPandTRIPsteelscanbecontinuouslyproducedinAnsteel.Toassurethicknessandflatnessofstrips,weoptimizedthehotrollingparametertogetlowdeformationresistance,optimizedrollingoiltogetfitfrictionalcoefficientandfixonthetargatrollingcurve.Togetmoreaccurateandrepetitiveresultsovertheproductionshifts,theMathematicalModel(MM)isusedinAnsteel.TheMManalysesinformationtransmittedbyvarioussensorsandtransmitters,comparesthecollecteddatawiththechosenparametersandadjuststhesettingsofthevariouspiecesofequipmenttohoneontheparametersetpoints.Atpresent,thekeyproductiontechnologiesofAHSSweregraspedbycoldrollingmillAnsteel,andAnsteelisthefirstcompanytoapplytheTRIPwiththegradeof780MPa.

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  • 简介:制造在上的影响张力并且3种制造方法生产的铜电影的疲劳行为被调查。张力、高的周期疲劳测试用作者开发的测试机器被执行。幼仔的moduli(72,71和69GPa,分别地)比文学价值低(108鈥?45GPa)当收益力量象358,350和346MPa一样高时,分别地并且最终的力量作为462,456和446MPa分别地。在3种电影的张力的性质没有许多差别。在3种电影的疲劳性质有小差别,但是他们之一在低周期区域比其它在高周期区域和更长的疲劳生活比其它过更短的疲劳生活。

  • 标签: 力学性质 薄膜 高周疲劳
  • 简介:Thecontrolofcoreplasmaandimpuritylevelofedgeplasmahasbeengreatlyimprovedwiththedevelopmentofcontrolledfusiontechnology.Refractorymetaltungstenoritsalloywaspaidmoreattentionsowingtoitshighmeltingtemperature,goodthermal

  • 标签: 钨镀层 等离子体防面材料 聚变控制 CVD 热力匹配
  • 简介:Fourtriazoleenantiomersofdiclobutrazol(erythroform)(1),paclobutrazol(erythroform)(2),diniconazole(3)anduniconazole(4)havebeenseparatedbyhighperformanceliquidchro-matography(HPLC)onchiralstationaryphase(CSP)OA-4700.Chromatographicdataandachiralrecongnitionmodelarepresentedfortheseparationofthesepesticideenantiomers.Theinfluenceofcolumntemperatureandcompositionofmobilephasehavebeendescribed.

  • 标签: TRIAZOLE PESTICIDE enantiomeric separation CHIRAL STATIONARY
  • 简介:MechanicalqualityfactorQmisakeycharacteristicparameterofHigh-overtonebulkacousticresonator(HBAR).Theeffectsofstructureparameter(thickness)andperfor?manceparameters(characteristicimpedanceandmechanicalattenuationfactor)ofsubstrate,piezoelectricfilmandelectrodeconstitutingHBARonQmarecarriedout.TherelationshipsbetweenQmandtheseparametersareobtainedbyalumpedparameterequivalentcircuitinsteadofdistributedparameterequivalentcircuitneartheresonancefrequency,andthean?alyticalexpressionsoiQmaregiven.TheresultsshowthatQmincreasesnon-monotonicallywiththecontinuousincreaseofthesubstratethicknessforHBARwithcertainpiezoelectricfilmthickness,anditapproachestothesubstratematerialmechanicalqualityfactorasthesubstratethicknessislarge.QmdecreaseswavilywiththecontinuousincreaseofthepiezoelectricfilmthicknessforHBARwithcertainsubstratethickness.SapphireandYAGwithlowmechanicallossareappropriateasthesubstratetogetalargerQm-TheelectrodelossmustbeconsideredsinceitcanreduceQm-ComparedwithAuelectrode,A1electrodewithlowerlosscanobtainhigherQmwhentheappropriateelectrodethicknessisselected.Inaddition,Qmdecreaseswiththeincreaseoffrequency.TheseresultsprovidethetheoreticalbasisforoptimizingtheparametersofHBARandshowthattrade-oflFsbetweenQmandmustbeconsideredinthedesignbecausetheirchangesareofteninconsistent.

  • 标签: RESONATOR PIEZOELECTRIC IMPEDANCE inconsistent instead SILICA
  • 简介:Pantographsystemofhigh-speedtrainsbecomesignificantsourceofaerodynamicnoisewhentravellingspeedexceeds300km/h.Inthispaper,ahybridmethodofnon-linearacousticsolver(NLAS)andFfowcsWilliams-Hawkings(FW-H)acousticanalogyisusedtopredicttheaerodynamicnoiseofpantographsysteminthisspeedrange.Whenthesimulationmethodisvalidatedbyabenchmarkproblemofflowsaroundacylinderoffinitespan,wecalculatethenearflowfieldandfaracousticfieldsurroundingthepantographsystem.Andthen,thefrequencyspectraandacousticattenuationwithdistanceareanalyzed,showingthatthepantographsystemnoiseisatypicalbroadbandonewithmostacousticpowerrestrictedinthemedium-highfrequencyrangefrom200Hzto5kHz.Theaerodynamicnoiseofpantographsystemsradiatesoutwardsintheformofsphericalwavesinthefarfield.Analysisoftheoverallsoundpressurelevel(OASPL)atdifferentspeedsexhibitsthattheacousticpowergrowsapproximatelyasthe4thpoweroftrainspeed.Thecomparisonofnoisereductioneffectsforfourtypesofpantographcoversdemonstratesthatonlycase1canlessenthetotalnoisebyabout3dBasbafflesonbothsidescanshieldsoundwaveinthespanwisedirection.ThecoversproduceadditionalaerodynamicnoisethemselvesintheotherthreecasesandleadtotheriseofOASPLs.

  • 标签: 空气动力噪声 高速列车 受电弓 系统 辐射 空气动力性噪声
  • 简介:现在的学习是为检测HIFU调查微分成像方法(高紧张集中了超声)导致的损害和为有木头的损害评估的变细的变化的评价光谱差别算法。在vitro的牛的肌肉和肝的实验结果被获得。为损害察觉的几个算法-绝对差别(广告),加绝对差别(悲伤)并且加摆平的差别(SSD)-与几种窗户尺寸和阀值价值被分析。当时,三个变细参数与相比评估织物的度损坏。它被发现吝啬的变细的那个变化()是一个有效参数评估损害。

  • 标签: 超声成像 诱导损害 高强度聚焦超声 评价
  • 简介:Thisstudyresearchescoldrolledultrahighstrengthmartensiticsteelprocessedbywaterquenching.Itisfoundthatboththequenchingandoverageingtemperaturesgreatlyinfluencethemechanicalpropertiesofmartensiticsteel.Atensilestrengthof1500MPacanbeobtainedfrom0.2%C-1.8%Mnsteelbysoakingat840℃,quenchingat700℃andoverageingat200℃forseveralminutes.Thecontinuouscoolingtransformation(CCT)diagramrevealsthatfullmartensitecanbeobtainedatacoolingrateof100℃/sorhigher;andatacoolingrateof3-10℃/s,austenitebarelydecomposesat700℃.Forsteelwith0.2%carbonandlessmanganese,austenitedecompositionoccursbeforeitiscooledto700℃atacoolingrateof3-10℃/s,whichleadstolowertensilestrength.Itispossibletoreducethemanganesecontentofthe1500MPamartensiticsteelbyincreasingthequenchingtemperature.Toincreasethequenchingtemperature,thecontrolofflatnessduringwaterquenchingbecomesamajorconcern.

  • 标签: 高拉伸性钢板 冷却程序 炼钢过程 操作程序
  • 简介:Alow-thresholdRamaneffectinakilowattytterbium-dopednarrowbandfiberamplifiersystemisreported.TheRamanStokeslightat1120nmisachievedwiththetotaloutputpowerofonly~400W,indicatingthattheRamanthresholdofthiskilowattcodirectionalpumpedcontinuouswavefiberamplifierismuchlowerthanthepredictedvalueestimatedbytheclassicformula.Tofigureoutthemechanismofthisphenomenon,simulationsbasedonthegeneralstimulatedRamanscattering(SRS)modelareanalyzedindicatingthatthekeyfactoristhecouplingbetweenfour-wavemixing(FWM)andSRS.Thesimulationresultsareingoodagreementwithourexperiments.

  • 标签: 光纤放大器 拉曼效应 低阈值 窄带 高功率 受激拉曼散射
  • 简介:Thecoherenceisameasurefortheaccuracyoftheinterferometricphase,andthesyntheticapertureradar(SAR)interferometriccoherenceisaffectedbyseveralsourcesofthedecorrelationnoise.ForthecircularSAR(CSAR)imaginggeometry,thesystemresponsefunctionisintheformoftheBesselfunctionwhichbringsahighsidelobe,andthehighsidelobeofCSARwillbeanimportantfactorinfluencingtheinterferometriccoherence.Theeffectofthehighsidelobeonthecoherenceisanalyzedanddeduced.BasedontheinterferometriccharacteristicsoftheslightdifferenceintheviewinganglesandthepotentialpixeloffsetintheinterferometricSAR(InSAR)images,arelationbetweentheradarimpulseresponseandthecoherencelossfunctionisderived.Fromtherelationalmodel,thecoherencelossfunctionduetothehighsidelobeofCSARisthendeduced,andcomparedwiththatoftheconventionalSAR.ItisshownthatthehighsidelobeofCSARfocusingsignalwillseverelyaffectthebaselinedecorrelationandcoregistrationdecorrelation.SimulationresultsconfirmthetheoreticalanalysisandquantitativelyshowthebaselineandcoregistrationdecorrelationdegradationduetothehighsidelobesofCSAR.

  • 标签: SAR成像 干涉相位 相干性 旁瓣 干涉合成孔径雷达 几何
  • 简介:Thecharacteristicsoflow-frequencyelectricalnoise,voltage-current(V-I)andelectricalderivationfor980nmInGaAsP/InGaAs/GaAshighpowerdoublequantumwelllasers(DQWLs)aremeasuredunderdifferentconditions.Thecorrelationofthelow-frequencyelectricalnoisewithsurfacenon-radiativecurrentofdevicesisdiscussed.Theresultsindicatethelow-frequencyelectricalnoiseof980nmDQWLswithhighpowerismainly1/fnoiseandhasgoodrelationwiththedevicesurfacecurrentatlowinjection.

  • 标签: 非辐射电流 半导体激光器 大功率 电噪声
  • 简介:IntroductionMoleculeimprintingtechnologyhasmadegreatprogressinmakingchiralstationaryphasewithpredeterminedchiralselectivityagainstenantiomerssuchasaminoacidandtheirderivatives;sugarandtheirderivatives;naproxenandmethylbenZylamine’-’.Functionalmonomer...

  • 标签: MOLECULE IMPRINTING CHIRAL separation stationals phase