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  • 简介:Anovelfabricationprocessformicropatternswithcurvaturewasintroduced.Thecurvedstructuresweremadebycompensatingrectangularmicrostructureswithliquidphotoresistlayer.Becauseofthesurfacetensionoftheliquidinmicroscale,variousshapesofmeniscuscanbemadeonthemicrochannels.Themicrochannelsweremadeonthesiliconsubstrateinadvance,andthentheliquidlayerwascoatedonthemicrochannels.Fromthenatureofliquidbehavior,thecurvedpatternswithsmoothsurfaceareobtained,whichcannotbemadeeasilywiththeconventionalmechanicalmachining,aswellaswiththemicrofabricationprocesses,suchaswetanddryetching.Withthisprinciple,itisexpectedthatthesmoothandcurvedsurfacescanbemadebysimpleprocessesandtheresultscanbeappliedwidely,suchasopticalpatterns.

  • 标签: 液态光致抗蚀剂 微结构 制备 弧形 微细加工工艺 表面光滑
  • 简介:WereportamonolithicTm:YLFmicrolaserinthisLetter.Inordertoimprovetherelaxationoscillationofthelaser,bothendsofthecrystalarecoated,makingtheTm:YLFcrystalitselfaresonantcavity.Themicrolaserispumpedbya792nmlaserdiodeoperatedinthecontinuouswave(CW)mode.Weobtainmaximumoutputpowersof7.78and10.4Watthetotalincidentpowerof43.6Wwithfocuslensesof37.5and40mm,respectively,correspondingtotheslopeefficienciesof25.6%and40.0%andtheoptical–opticalconversionefficienciesof17.8%and23.8%.Itisclearthattheamplitudeoftherelaxationoscillationissmallerandthebeamqualityisbetterwiththefocuslengthof37.5mm;however,thelaserwiththefocuslengthof40mmproducesahigheroutputpowerandamorestablewavelengthcenteringat1878.44nm.

  • 标签: YLF晶体 激光器 TM 单片 最大输出功率 性能
  • 简介:点火的分叉分析和催化燃烧在的扑灭一突然微隧道被执行,laminar模型作为流动模型合并了。横向的Thiele模量和滞留时间的平方被用作分叉参数。点火和扑灭行为上的不同参数的影响被调查。所有这些参数在点火和扑灭的分叉行为上有大效果在,这被显示出突然微隧道。燃烧的分叉行为上的流动模型的效果也被分析。结果证明与扁平的速度侧面模型比较,为laminar模型的案例,点火的温度和燃烧的扑灭更高,不稳定的多重答案区域更大。

  • 标签: 催化燃烧 分叉理论 热学 热处理
  • 简介:WhatisacredibleseismicprecursorinobservationofdeformationArealseismicprecursoroughttoberesultedfromthevariationsintheearthstrainandstress.Thedeformationobservationcanprovidetheinformationduringearthquakegestationandoccurrenceperiodforus.Usuallytheseismicprecursorscanbedividedintofieldandepicentralregionprecursors.Theprecursorinformationisveryusefulforseismicpredictionfromepicentralregionornearepicentralregion.Micro-deformationobservationmainlyincludestilt,strainandgravityobservation.ComparedwithGPS,geodesyandmobiledeformationobservation,micro-deformation(tilt,strain)showsthechangeofdeformationwhichiscontinualinalimitedvolumewithdominantobservedrangeof10(6~10(10m.Becausethevariationofthecrustalnatureandcrackingcanbedirectlyobtainedbymicro-deformationobservation,itisaneffectivewaytofindmiddle-shorttermandshort-termprecursor.

  • 标签: MICRO-DEFORMATION PRECURSOR of SHORT-TERM STRONG earthquake
  • 简介:Inthisstudy,micro-hollowcathodedischarge(MHCD)isinvestigatedbyafluidmodelwithdrift-diffusionapproximation.TheMHCdeviceisacathode/dielectric/anodesandwichstructurewithoneholeofadiameterD=200μm.ThegasisaNe/Xemixtureatapressurep=50~500Torr.Theevolutionsofthedischargeshowthattherearetwodifferentdischargemodes.AtlargerpDthedischargeplasmaandhighdensityexcitedspeciesexpandalongthecathodesurfaceand,aringeddischargemodeisformed.AtsmallerpD,thedischargeplasmaandtheexcitedspeciesexpandalongtheaxisofthecathodeaperturetoformacolumnardischarge.

  • 标签: 微空心阴极放电 放电模式 放电等离子体 近似模型 移动设备 夹层结构
  • 简介:Thispaperdescribestheuseofoverlappinggridsforthecalculationofflowaroundsingleandmultiple-particleconfigurationsatthemicroscale.ThebasicequationsforcalculationarethoseforconservationofmassandmomentumwhicharesolvedusingacommonFinite-Volumeformulation.Thehydrodynamicparticle-particleandparticle-wallinteractioncanbecalculatedbyusinganoverlappingorChimeragridscheme.Withthegridstructuringprocedureitispossibletousesimpleandstructuredgridsaroundtheparticlesandtheoverallmaingridgeometry.Theparticlegridsarelappedoverthemaingridsuchthattheycanmoveindependentlyaftereachtimestepwithoutremeshingthewholegeometry.Thepapergivesresultsforthevalidationofthecodedevelopedforgeneraltestcases,forarotatingellipsoidinsimpleshearflow,theflowaroundparticlesattachedtoawall,themotionofaparticleinthevicinityofawallandsomeresultsfortheflowthroughapackedbedconfiguration.

  • 标签: 粒子流 数字仿真 叶栅重复 颗粒-壁作用 填充层 分子运动
  • 简介:Inthispaper,wepresentahighspeedautofocussystemformicrosystemapplicationsanddesignalook-up-tablebasedautofocusingalgorithmforapplicationswhenatargetobjectisalwaysvisible,e.g.,manufacturingpartswithalignmentfiducials.Weperformanevaluationof24focusmeasurestoverifythatwhichfocusmeasureisthebestforthelook-up-tablebasedmethod.Fromtheevaluation,wefindthattheChebyshevmoments-basedfocusmeasure(CHEB)isthemostsuitable.Furthermore,wealsodevelopalook-up-tablebasedautofocussystemthatusesCHEBasthefocusmeasure.Intrainingphase,weofflineconstructatablefromtrainingimagesofanobjectthatarecapturedatseverallensdistances.Eachentryoftableconsistsoffocusmeasurecomputedfromimageandlensdistance.Inworkingphase,givenaninputimage,thealgorithmfirstcomputesthefocusmeasureandthenfindsthebestmatchfocusmeasurefromthetableandlooksupthecorrespondinglenspositionformovingitintothein-focusposition.Ouralgorithmcanperformautofocusingwithinonly2stepsoflensmoving.Theexperimentshowsthatthesystemcanperformhighspeedautofocusingofmicroobjects.

  • 标签: 自动对焦系统 微系统 应用 自动聚焦算法 训练图像 镜头运动
  • 简介:Anoveldischargedeviceisdesignedonthebasisoftheconfigurationofmicro-hollowcathodedischarge(MHCD).ByusingmanyMHCDsinparallelconnection,amicro-dischargearraycanbeconstructed.Withthemicro-dischargearray,ahigh-pressurehigh-currentdensityglowdischargeplasmascanbeformedtomakeaplasmadisplaypanel(PDP).Anairdischargeexperimentisfinishedwiththedischargedevice.Thestabledirectcurrentglowdischargeisformedunderthepressurefrom20Torrto500Torr.Thevoltage-currentcharacteristiccurveandthedischargephotographarenoted.Thevoltage-currentcharacteristiccurvehasapositivedifferentialresistancecoefficientonthewholedischargerange.Theestimatedcurrentdensityreaches70.1A/cm3,thepowerdensityis3.6×104W/cm3,andtheelectrondensityisintheorderof1013cm-3atp=200TorrandID=10mA.TheexperimentalresultsindicatethatthedesigneddischargedeviceisappropriateforPDP.

  • 标签: 等离子显示器 面板 放电装置 驱动程序
  • 简介:JiaXiangdejustdidn’tknowwhattodowhen,fiveyearsago,helosthisjobatastate-ownedchemicalfactory.Hewasgivenmi"unemploymentpay"of200yuan(US$24.1)permonthforhisfamilyofseven."Mywilehadnojobandlifewasreallyhardforus,"herecalls."IhadthoughtIwouldbedoneforuntilthegovernmentsteppedintohelp.Igotapettyloanfromthegovernment,andthathashelpedmeturnanewleafinlife."

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  • 简介:TheRamanspectrafromleukemiccellline(HL60)andnormalhumanperipheralbloodmononuclearceils(PBMCs)areobtainedbyconfocalmicro-Ramanspectroscopyusingnear-infraredlaser(785nm)excitation.Thescanningrangeisfrom500to2000cm-1.ThetwoaverageRamanspectraofnormalPBMCsandcarcinomacellshavecleardifferencesbecausetheirstructureandamountofnucleicacid,protein,andothermajormoleculesarechanged.Thespectraarealsocomparedandanalyzedbyprincipalcomponentanalysis(PCA)todemonstratethetwodistinctclustersofnormalandtransformedcells.Thesensitivityofthistechniqueforidentifyingtransformedcellsis100%.更多还原

  • 标签: 光谱学 黎曼光谱 白血病细胞 激光
  • 简介:Micro-retailenterprises(MREs)havehadtoadapttochangingconditionsinregardstomobilepayments(m-payments)andaccesstoloans.TheauthorsbuiltonthepublishedresultsoftwoprevioussurveysofMREs.Onethousandninehundredandninety-eightMREsinfourcitiesinChinaweresurveyedinMayandJuneof2018todeterminetheuseandimportanceofm-paymentstotheirbusiness,theiraccesstoloans,andpatternsofentrepreneurship.Whilesometrendsremainunchanged,atleasttwosignificantfindingsemerge.M-paymentshavenotonlygainedalmostuniversalacceptancebyMREsinChina;theyaretheoverwhelminglypreferredpaymentmethod.Inourlastpaper,wearguedthat“m-paymentsmayrepresentaformofleapfroggingtechnologywhichwillspurgrowthinthissector”andthispaperprovidesadditionalevidencethisisoccurring.M-paymentsshoweverysignofbeinganexampleofaleapfroggingtechnologythatisquicklychangingtherulesforretailintheMREsectorandopeningnewopportunitiesforbusinesseswhileloweringtransactioncosts,reducingfraud,andimprovingcustomersatisfaction.Thereareintriguingimplications,includingchangestothepaceofm-paymentsreplacingcreditcards.Second,whileitremainstruethatoverall,accesstoloansforMREsislimited;thereisagreatdealofvariationbetweentier-onecitiesandtier-twoandtier-threecities.

  • 标签: micro-retail enterprise(MRE) mobile payment(m-payment) Chinese ENTREPRENEUR
  • 简介:Anexperimentalstudywascarriedouttoinvestigatetheinfluenceofdoubletwisted-tapeinserts(DTs)inmicro-fintubes(MFs)onheattransfer,frictionfactorandthermalperformancefactorcharacteristicsofthecompounddevicesinthefollowingconfigurations:(1)twistedtapesactedinthesamedirection(forco-swirl)whileMFandtwistedtapesactedinthesame(parallel)direction(MF-CoDTs:P),(2)twistedtapesactedinthesamedirection(forco-swirl)whilemicro-fintubeandtwistedtapesactedinoppositedirections(MF-CoDTs:O)and(3)twistedtapesactedinoppositedirectionsforcounterswirl(MF-CDTs).TheMFaloneandtheMFequippedwithasingletwistedtapeinparallel/oppositearrangementwerealsoconsideredforcomparison.TheexperimentswereconductedfortheflowswiththeReynoldsnumbersbetween5650and17000,underuniformheatfluxcondition.TheexperimentalresultsindicatethatMF-CDTsinducestrongerswirl/turbulenceflow,resultinginhigherheattransferrate,frictionfactorandthermalperformancefactorthanothercombineddevices.ThethermalperformancefactorsassociatedwiththeuseofMF-CDTswerefoundtobehigherthanthoseassociatedwiththeusesofMF-CoDTs:P,MF-CoDTs:OandMFaloneupto9.3%,6.5%and56.4%,respectively.TheempiricalcorrelationsdevelopedusingthepresentexperimentaldatafortheNusseltnumber,frictionfactorandthermalperformancefactorarealsoreported.

  • 标签: 传热特性 微肋管 扭带 配备 性能系数 实验性
  • 简介:Naturalsurfaceswithsuperhydrophobicpropertiesoftenhavemicroorhierarchicalstructures.Inthispaper,thewettingbehavioursofasingledropletonbiomimeticmicrostructuredsurfaceswithdifferentroughnessparametersareinvestigated.Atheoreticalmodelisproposedtostudywettingtransitions.Theresultsoftheoreticalanalysisarecomparedwiththoseofexperimentindicatingthattheproposedmodelcaneffectivelypredictthewettingtransition.Furthermore,anumericalsimulationbasedonthemesoscaleLatticeBoltzmannMethod(LBM)isperformedtostudydynamiccontactangles,contactlines,andlocalvelocityfieldsforthecasethatadropletdisplaysonthemicrostructuredsurface.Asphericalwaterdropletwithrs=15μmfallsdowntoabiomimeticsquare-postpatternedsurfaceundertheforceofgravitywithaninitialvelocityof0.01m·s-1andaninitialverticaldistanceof20μmfromdropletcentretothetopofpots.Inspiteofahigherinitialvelocity,thedropletcanstillstayinaCassiestate;moreover,itreachesanequilibriumstateatt≈17.5ms,whencontactangleis153.16°whichisslightlylowerthanthepredictionofCassie-Baxter’sequationwhichgivesθCB=154.40°.

  • 标签: BIOMIMETIC WETTING BEHAVIOURS ROUGHNESS surfaces contact
  • 简介:Dopedmicro-crystallinesiliconfilmsaredepositedattemperaturesaslowas400℃bythecatalyticchemicalvapordepositionmethodusingasilaneandhydrogengasmixture.ElectricalpropertiessuchasthecarrierconcentrationandtheHallmobilityareinvestigatedforvariousmeasuringtemperatures.Itisfoundthatthegrainsofmicro-crystallinesiliconarepreferentiallyorientedalongthe(220)direction,andthattheHallmobilityislargerthan8cm^2·V^-1·s^-1,thecarrierconcentrationisabout1×10^17cm^-1-1×10^19cm^-3atroomtemperature.

  • 标签: 化学气相沉积 霍尔迁移率 微单晶硅 载波传输性