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简介：Thefatiguelifeofnumerousaerospace,locomotive,automotiveandbiomedicalstructuresmaygobeyond10~8cycles.Determinationoflonglifefatiguebehaviorbecomesextremelyimportantforbetterunderstandinganddesignofthecomponentsandstructures.Initially,beforetheinventionofultrasonicfatiguetesting,mostoftheengineeringmaterialsweresupposedtoexhibitfatiguelifeupto10~7cyclesorless.Thispaperreviewscurrentunderstandingofsomefundamentalaspectsonthedevelopmentofacceleratedfatiguetestingmethodanditsapplicationinultra-highcyclefatigue,crackinitiationandgrowthmechanismsofinternalfracture,S-Ndiagram,fatiguelimitandlifeprediction,etc.

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简介：以便调查设计方法因为一台微离心的压缩机，它是一台极端微煤气的汽轮机的最重要的部件，有2-dimensional片的离心的impeller的二种类型被设计，生产并且测试。这些impellers与对方一起在南方的飞机上有中心的不同形状。而且，impeller的这些类型为5被成为次和期末考试的6次尺寸与4mm的外部直径指向离心的impeller以便为impellers估计类似。在impellers的表演特征之中的比较在表演和压缩机的类似上揭示了南方的配置的影响。

简介：我们在场在高度反响的媒介的极端慢的明亮、黑暗的光solitons的形成上的系统的研究。由调查，四一生拓宽了原子系统，即，三状态的A类型和串联类型计划，和四状态的N类型和cascade-typeschemes，我们证明在冷原子系统的如此的极端慢的soh'tons的形成是相当通用的现象。

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简介：Anultrathin,planar,broadbandmetalenscomposedofmetalrectangularsplit-ringresonators(MRSRRs)hasbeendesigned,whichshowsdual-polaritycharacteristicsfordifferenttypesofcircularlypolarized(CP)lightincidence.Thedesignedmetalenscanbeconsideredasthefocusinglensandthediverginglensunderleft-handedCPandright-handedCPlightincidence,respectively.Thephasediscontinuityofthecross-polarizedtransmissionlightisproducedbyoptical-axisrotationthroughmodulatingtwoarms’lengthsoftheMRSRR.TheMRSRRmetalenspossessesawavelength-controllablefocallengthandarelativelylargerchromaticaberrationcomparedwiththeconventionallenses.Andthefocallengthchangesfrom9to7μmwithincidentwavelengthfrom740to950nm.Thedual-polarityflatmetalensopensadoorfornewapplicationsofphasediscontinuitydevices,anditwillpromotethefabricatingcapabilityofon-chiporfiber-embeddedopticaldevices.

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简介：Thereareseveralpetawatt-scalelaserfacilitiesaroundtheworldandthefidelityofthepulsestotargetiscriticalinachievingthehighestfocusedintensitiesandthehighestpossiblecontrast.TheUnitedKingdomhasthreesuchlaserfacilitieswhicharecurrentlyopenforaccesstotheacademiccommunity:OrionatAWE,AldermastonandVulcan&Astra-GeminiattheCentralLaserFacility(CLF),STFC(ScienceandTechnologyFacilitiesCouncil)RutherfordAppletonLaboratory(RAL).Thesefacilitiesrepresentthetwomainclassesofpetawattfacilities:themixedOPCPA/Nd:glasshigh-energysystemsofOrionandVulcanandtheultra-short-pulseTi:SapphiresystemofAstraGemini.Manyofthetechniquesusedtoenhanceandcontrolthepulsegenerationanddeliverytotargethavebeenpioneeredonthesefacilities.Inthispaper,wepresentthesystemdesignswhichmakethispossibleanddiscussthecontrastenhancementschemesthathavebeenimplemented.

简介：Hydrodynamicpropertiesandstructureofstrongshockwavesinclassicaldenseheliumaresimulatedusingnon-equilibriummoleculardynamicsmethods.Theshockspeedinthesimulationreaches100km/sandtheMachnumberisover250,whichareclosetotheparametersofshockwavesintheimplosionprocessofinertialconfinementfusion.Thesimulationsshowthatthehigh-Mach-numbershockwavesindensemediahavenotabledifferencesfromweakshockwavesorthoseindilutegases.Theseresultswillprovideusefulinformationontheimplosionprocess,especiallythestructureofstrongshockwavefront,whichremainsanopenquestioninhydrodynamicsimulations.

简介：Thispaperproposesanultra-modifiedSSA(symmetricsequencealgorithm)ofspacevectormodulationofMC(matrixconverter).Theultra-modifiedtechniqueimprovesthedrawbacksofthemodifiedonewhereitprovidesareductionofthetotalharmonicdistortionforbothoutputvoltageandcurrent.AlsothispaperproposesamodifiedfeedforwardcontrolleroftheMCwithindirectspacevectormodulation.Themodifiedfeedforwardprovidesasolutionforthechangeintheoutputvoltageduetochangeinwindspeed,whereitprovidesaconstantoutputvoltagewithconstantfrequencyevenifthewindspeedchanged.SomeoftheadvantagesofMCareintroducedinthispaper.TheseadvantagesrepresentedintheoutputfrequencyofMCwhichmaybegreaterthantheinputfrequency,controllingrmsvalueoftheoutputvoltageandtheabilitytocontroltheIDF(inputdisplacementfactor).Attheendofthispapersimulationandexperimentalresultsareintroducedwhichgiveapreciseprooftotheproposedalgorithms.

简介：Inthispaper,anovelcopper-basedcatalystforFCCgasolineimprovingtheabilityofremovalthesulfurandavoidingthelossoftheoctanenumberfromolefinsaturationbyreactiveadsorptiondesulfurization(RADS)wasinvestigated.TheseriesofCu/ZnO-Al2O3catalystswerecharacterizedbyX-raypowderdiffraction(XRD),N2adsorptionanalysisandtemperature-programmedreduction(TPR)studies,X-rayphotoelectronspectroscopy(XPS),scanningelectronmicroscope(SEM)andtransmissionelectronmicroscopy(TEM).Theexperimentresultsshowedthatthecatalystshadanoptimumdesulfurizationabilitywithcopperloading6wt%,whichthesulfurcontentsofproductdecreasedlessthan10μg/gandolefincontentsdecreasedfrom16.19%to14.14%forthelongperiodoperation.TheappropriateCuloadingcontentcouldleadtothehighactiveandlowapparentactivationenergy(Ea).Therefore,theCu-basedcatalystmaybecomeanovelcatalystforsecond-generationforreactiveadsorptiondesulfurization,whichachievesthehighdesulfurizationactiveandlowolefinssaturationtosatisfytheupgradingtheproduct.

简介：Weexperimentallydemonstratetheopticalpropertiesofgratingsengravedinasingle-modewaveguidefabricatedontopofadielectricmultilayerplatform.ThestructurecanbeapproachedasareflectorforBloch-surface-wavebasedtwo-dimensionalopticalsystems.Thegratingshavebeenfabricatedonathin(～λ∕25)titaniumdioxidelayerwithathicknessofafewtensofnanometersdepositedonthetopofamultilayerplatform.Theopticalpropertiesofthegratingshavebeencharacterizedinthenearfieldwiththeaidofmulti-heterodynescanningnearfieldopticalmicroscopy.Weinvestigatethesurfacewave’sinterferencepattern,producedbyincidentandreflectedlightinfrontofthegratings.ThepresentedgratingsbehaveasanefficientBloch-surface–wave-basedreflectorattelecommunicationwavelength.

简介：Wedemonstrateanultra-low-thresholdphononlaserusingacoupled-microtoroid-cavitysystembyintroducinganovelcouplingapproach.Theschemeexhibitsbothhighopticalqualityfactorsandhighmechanicalqualityfactors.Wehaveexperimentallyobtainedthemechanicalqualityfactorupto18,000invacuumforaradialbreathingmodeof59.2MHz.Themeasuredphononlasingthresholdisaslowas1.2μW,whichis～5timeslowerthanthepreviousresult.

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简介：在极端薄的电影在dewetting上理解nanoparticles的影响，两个都，线性稳定性理论和数字模拟在现在的学习被执行，与考虑摆动结构(OS)力量。长规模近似被利用为电影厚度和nanoparticle集中简化水动力学和散开方程到一个非线性的系统。结果证明nanoparticles的存在通常压制dewetting过程。为这现象负责的二物理机制在现在的学习被探讨。当摆动的结构的力量相对更小时，电影进化的必要特征类似于没有粒子的流动的盒子。线性生长率的减小和电影破裂的推迟能由于nanoparticles的存在被归因于粘性的增长。在另一方面，当OS力量的紧张变得更强壮时，电影的逐步的变瘦能被观察它阻止这部电影破裂。数字模拟显示这现象被一个稳定的地区的存在由于结构的力量的摆动的性质引起。另一有趣的发现是nanoparticle集中的分发的不一致可能使动摇一部spinodally稳定的电影，和扳机电影dewetting的出现。

简介：吸收的时间的进化由单个飞米导致了第二脉搏(130fs，800nm)与高度，在LiNbO3的紧张用探查阴影成像技术被获得以便调查导致光的选举松驰过程。由浸透有高紧张激光脉搏的极化子密度，微微秒时间规模上的极端快的腐烂过程被观察。Thedecay时间常数是大约141ps，它被归因于直接内部乐队election-holerecombination过程。

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