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21 个结果
  • 简介:Basedonthegivenreactionconditionandmedium,thegrowthofmicro-andnanocrystalscanbedividedintofourtypes,growthinsolutionatnormalpressure,hydrothermalgrowth,solvothermalgrowth,andmolten-saltgrowth.Whenthewaterororganicsolventasthereactionmedium,surfactant,suchassodiumdodecylbenzenesulfonate,canbeaddedtoregulatethe

  • 标签: 英语 阅读 理解 纳米材料与技术
  • 简介:AIM:ToscreenmicroRNAs(miRNAs)andsetuptargetmiRNAsinpterygium.METHODS:PrimaryfibroblastswereisolatedfrompterygiumandTenon’scapsuleandcultured.ImmunocytochemicalanalysisandWesternblottingwereperformedtoconfirmthecultureoffibroblasts.Inall,1733miRNAswerescreenedinthefirststepbyusingGeneChip?miRNA3.0Array.SpecificmiRNAsinvolvedinthepathogenesisofpterygiumweresubsequentlydeterminedusingthefollowingcriteria:1)highreproducibilityinarepetitivetest;2)baselogvalueof>7.0forbothcontrolandpterygialfibroblasts;and3)logratioof>1.0betweenpterygialfibroblastsandcontrolfibroblasts.RESULTS:Primaryscreeningshowedthat887/1733miRNAswereup-regulatedand846/1733miRNAsweredown-regulatedinpterygialfibroblastscomparedwiththoseincontrolfibroblasts.Ofthe1733miRNAsscreened,4miRNAs,namely,miRNA-143a-3p,miRNA-181a-2-3p,miRNA-377-5pandmiRNA-411a-5p,mettheabove-mentionedcriteria.Primaryscreeningshowedthatthese4miRNAswereup-regulatedinpterygialfibroblastscomparedwithcontrolfibroblastsandthatmiRNA-143a-3phadthehighestmeanratiocomparedwiththemiRNAsincontrolfibroblasts.CONCLUSION:miRNA-143a-3p,miRNA-181a-2-3p,miRNA-377-5pandmiRNA-411a-5pareup-regulatedinpterygialfibroblastscomparedwithcontrolfibroblasts,suggestingtheirinvolvementinthepathogenesisofpterygium.

  • 标签: MICRORNA PTERYGIUM FIBROBLAST
  • 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: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:Livercancer,primarilyhepatocellularcarcinoma(HCC),isamajorcauseofcancer-relateddeathworldwide.HCCisasuitablemodelofinflammation-inducedcancerbecausemorethan90%ofHCCcasesarecausedbyliverdamageandchronicinflammation.Severalinflammatoryresponsepathways,suchasNF-κBandJAK/STAT3signalingpathways,playrolesinthecrosstalkbetweeninflammationandHCC.MicroRNAs(miRNAs)areevolutionarilyconserved,shortendogenous,non-codingsingle-strandedRNAsthatareinvolvedinvariousbiologicalandpathologicalprocessesbyregulatinggeneexpressionandproteintranslation.EvidenceshowedthatmiRNAsplayapivotalroleinhepatitisvirusinfectionandserveaspromotersorinhibitorsofinflammatoryresponse.AberrantmiRNAwasobservedduringliverinflammationandHCC.ManydysregulatedmiRNAsmodulatetheinitiationandprogressionofinflammation-inducedHCC.ThisreviewsummarizestheroleandfunctionsofmiRNAsininflammation-associatedHCC,aswellasthedesignedtherapeuticstargetingmiRNAstotreatliverinflammationandHCC.

  • 标签: 慢性炎症 微RNA 肝癌 MIRNAS microRNA NF-κB
  • 简介:Fabricationofmicrogratingsusingafemtosecondlaserexposuresystemisexperimentallyinvestigatedfortheelectronmoirémethod.Microholesandlinesarefirstlyetchedforparameterstudy.Gratingprofileistheoreticallyoptimizedtoformhighqualitymoirépatterns.Forademonstration,aparallelgratingisfabricatedonaspecimenofquartzglass.Theminimumlinewidthandthedistancebetweentwoadjacentlinesarebothsettobe1μm,andthefrequencyofgratingis500lines/mm.Theexperimentalresultsindicatethatthequalityofgratingsisgoodandtherelativeerrorofthegratingspitchisabout1.5%.Basedonmoirémethod,scanningelectronmicroscope(SEM)moirépatternsareobservedclearly,whichmanifeststhatgratingsfabricatedwiththefemtosecondlaserexposureissuitableformicroscaledeformationmeasurement.

  • 标签: 光栅制作 飞秒激光 微尺度 扫描电子显微镜 莫尔法 曝光系统
  • 简介:高温度液体被注入微尺寸毛状并且它的轻繁殖行为被调查。我们集中于抽方法的二不同液体。第一个方法能把高温度液体听输入微尺寸由使用一个高压力差别系统毛状。在抽以后,与光搬运人一起连接的单个模式纤维(SMF)基于微波interferometry(OCMI)系统被用来测量不同液体听层次在微尺寸毛状。第二个方法能把房间温度引擎油输入由使用注射泵毛状。当液体被输入时,这个方法能避免空气水泡毛状。

  • 标签: 高温液体 毛细管 微尺度 光传输 差分系统 微波干涉仪
  • 简介:Propagation-basedphase-contrastimagingwassimulatedbasedonparaxialFresnel-Kirchoffdiffractionintegralandsphericalwaveillumination.Underadevelopedmicro-CTsystemparameters,theeffectsoffocal-spotsizeandimaginggeometryonphase-contrastimaginghavebeeninvestigatedusinga2-mm-thicknesspolystyreneedgephantom.Anequivalentmono-energywasusedtosubstitutethepolychromaticspectrumofthemicro-focusX-raysource.Toconsidereffectsoffocal-spotsizeanddetectorresolution,theobtainedphase-contrastimagewithanidealpointsourcewasconvolvedwithsourceintensitydistributionandpointspreadfunctionofdetector.Simulationsshowreasonableinfluencesofthetwoparameterswhichareingoodagreementwithexperimentalresults.

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  • 简介:我们在这份报纸在场计划方法的一条柔韧的联机路径,它在否认GPS、撒布障碍的环境安全地允许一只微旋转飞机雄蜂到苍蝇与限制了机载的计算力量。途径基于到二个点边界价值问题(TPBVP)的一张高效地管理的格子地图和一个靠近形式的答案。而TPBVP的答案产生光滑的轨道,格子地图帮助轨道评估。最后,交换算法的一条最高层的轨道被利用最小化计算费用。建议途径的优点包括它计算资源的保存,轨道产生的坚韧性和对未知环境的反应的活泼。结果在实际雄蜂平台上被认识到并且成功地在真实飞行测试示威了。飞行测试的录像能被发现在:http://uav.ece.nus.edu.sg/robust-online-path-planning-Lai2015.html。

  • 标签: 无人机平台 路径规划 环境 在线 两点边值问题 旋翼
  • 简介:Inthispaper,weproposeaninstantaneousphase-steppingmethodfordeterminingphasedistributionofinterferencefringesutilizingacamerathatisequippedwithamicro-polarizerarrayonthesensorplane.AnopticalsetupofpolarizationinterferometryusingaMach–Zehnderinterferometerwithtwopolarizersisconstructed.Lightemergingfromtheinterferometerisrecordedusingacamerathathasamicro-polarizerarray.Thismicro-polarizerarrayhasfourdifferentopticalaxes.Thatis,animageobtainedbythecameracontainsfourtypesofinformationcorrespondingtofourdifferentopticalaxesofthepolarizer.Thefourimagesseparatedfromtheimagerecordedbythecameraarereconstructedusinggraylevelinterpolation.Subsequently,thedistributionsoftheStokesparametersthatrepresentthestateofpolarizationarecalculatedfromthefourimages.ThephasedistributionoftheinterferencefringepatternproducedbytheMach–ZehnderinterferometeristhenobtainedfromtheseStokesparameters.Theeffectivenessoftheproposedmethodisdemonstratedbymeasuringastaticcarrierpatternandtime-variantfringepatterns.Itisemphasizedthatthismethodisapplicabletotime-variantphenomenabecausemultipleexposuresareunnecessaryforsufficientdataacquisitioninthecompletionofthephaseanalysis.

  • 标签: 微偏振器 干涉条纹 瞬时相位 阵列 相位偏移 斯托克斯参数
  • 简介:Aneffectivedesignmethodoffreeformmicrolensarrayispresentedforshapingvariedlaserbeamsintoprescribedrectangularillumination.Thevariableseparationmappingisappliedtodesignconcavefreeformsurfacesforconstructingafreeformlensarray.Severaldedicatedexamplesshowthatthedesignedfreeformopticallensarraycanachieveaprescribedrectangularilluminationpattern,especiallywithoutconsideringtheinitialstatesofincidentlaserbeams.Bothhighcollectionefficiencyandgoodspatialuniformitycanbeavailablesimultaneously.Toleranceanalysisisalsoperformedtodemonstratethatthisopticaldevicecanwellavoidfabricatingdifficultyinactualapplications.

  • 标签: 微透镜阵列 自由曲面 空间均匀性 激光束 矩形 成型机
  • 简介:基于Si的多层的结构广泛地在当前的微电子学被使用。在他们的准备期间,一些不同类的剩余应力被导致,导致在接口错配和表面精力和平导致结构失败之间的竞争。这个工作在多层的半导体heterostructure在剩余应力的测量上介绍方法学的研究。扫描电子显微镜学(SEM),micro-Raman光谱学(太太),和传播电子显微镜学(TEM)被使用测量多层的结构的几何参数。在拉曼光谱和压力/紧张在上之间的关系[100]并且[110]水晶取向被决定分别地启用表面和剖面图剩余压力分析。基于印射结果的拉曼,沿着多层的heterostructure的深度的剩余应力的分发成功地被获得。

  • 标签: 剩余应力 多层的半导体 heterostructure Micro-Raman 光谱学(太太) 拉紧的硅 金者硅
  • 简介:Inthisstudy,etherificationofginkgolideBanddimethylaminoethylchloridehydrochloridewasinvestigatedasamodelreactioninamicro-flowsystem(MFS),providingtheresultingethersinhighyieldwithfewersideeffects.Meanwhile,thisnovelprocessinMFSworkedwellforotherginkgolidesfromGinkgolbilobaandhalides,givingmoderateyields.

  • 标签: ETHERIFICATION Ginkgolide B 微流动的系统 很少副作用
  • 简介:Asimplemethodtofabricateone-dimensional(1-D)andtwo-dimensional(2-D)orderedmicro-andnano-scalepatternsisdevelopedbasedontheoriginalmastersfromopticaldiscs,usingnanoimprinttechnologyandsoftstamps.Polydimethylsiloxane(PDMS)wasusedtoreplicatethenegativeimageofthe1-DgratingpatternonthemastersofCD-R,DVD-RandBD-Ropticaldiscs,respectively,andthenthe1-DpatternononeofthePDMSstampswastransferredtoablankpolycarbonate(PC)substratebynanoimprint.The2-DorderedpatternswerefabricatedbythesecondimprintingusinganotherPDMSstamp.Different2-DperiodicpatternswereobtaineddependingonthePDMSstampsandtheanglebetweenthetwotimesofimprints.Thismethodmayprovideawayforthefabricationofcomplex2-Dpatternsusingsimple1-Dmasters.

  • 标签: 有序结构 纳米尺度 印章制作 光盘 PDMS印章 纳米压印技术
  • 简介:WecollectedacornsfromselectedQuercusroburandQuercuspetraeamothertreesgrowingatstationswithdifferentdepthstothewatertable.Weproducedpairsofmicro-cuttingsfromthesesingleacorns.Theobtainedpairsofcuttingsrepresentedphenotypesofhighsimilarityaccordingtophotosyntheticparameters.Thesepairsofcuttingswereusedtotesttheplasticityofresponsetocontrastingwaterregimes.Foreachpair,onecuttingwassubmittedtodroughtandtheotherwassubmittedtowaterlogging.Droughtresponsewasrecordedaccordingtogasexchangetraits(stomatalclosureandwateruseefficiency).TheresponsetowaterloggingwasrecordedaccordingtothecapacitytoformhypertrophiedlenticelsandtomaintaintheCO2assimilationrate.Intermediaryphenotypespresentingbothhighwateruseefficiencyandthecapacitytodevelophypertrophiedlenticelswereexpected.

  • 标签: 土壤水分 微扦插 可塑性 橡子 测试 水分利用效率
  • 简介:题目:悬浮等离子体喷涂过程中微纳米颗粒撞击基板的动力学模拟目的:研究微纳米颗粒在流场中的运动和传热特性,确定颗粒绕流的临界尺寸以及微纳米颗粒合适的喷涂距离。创新点:1.建立微纳米颗粒的受力和运动模型;2.推导颗粒粒径和斯托克斯数的关系,确定颗粒绕流的临界尺寸;3.确定适于微纳米颗粒的喷涂距离。方法:1.通过颗粒运动和传热的三维模型,模拟颗粒在等离子体流场中的运动和传热过程;2.对流场采用欧拉法进行求解,对颗粒采用拉格朗日法进行求解;3.动态追踪颗粒的轨迹和空间分布,从而得到颗粒的速度、温度和空间分布。结论:1.布朗力会影响纳米颗粒的分布;现有模型可以很好地模拟微纳米颗粒的行为。2.可以用斯托克斯数和粒径表征微纳米颗粒绕流的临界尺寸;当前工况下,临界粒径约为800nm。3.基板会影响流场结构和颗粒的空间分布;在当前研究中,得出有利于纳米颗粒沉积的喷涂距离约为50mm;对微米颗粒来说,喷涂距离应适当增大。4.微纳米颗粒的空间分布呈现不同的特点;纳米颗粒的分布区间更大,布朗力对纳米颗粒的作用比对微米颗粒更为显著。5.微纳米颗粒的运动和传热过程呈现不同的特点;纳米颗粒的惯性和热容小,因此它们的速度和温度变化更迅速。

  • 标签: 悬浮等离子体喷涂 斯托克斯数 布朗力 多相流 固体-流体相互作用
  • 简介:Room-temperatureterahertz(THz)detectorsindicateagreatpotentialintheimagingapplicationbecauseoftheirreal-time,compactbulk,andwidespectralbandrespondingcharacteristics.THzdetectorswithdifferentdimensionsbasedonamicro-bridgestructurehavebeendesignedandfabricatedtogetoptimizedmicro-bolometerparametersfromthetestresultsofmembranedeformation.Ananostructuredtitanium(Ti)thinfilmabsorberisintegratedinthemicro-bridgestructureoftheVOxmicro-bolometerbyacombinedprocessofmagnetronsputteringandreactiveionetching(RIE),anditsimprovementofTHzabsorptionisverifiedbyanopticalcharacteristicsmesurement.Continuous-waveTHzdetectionandimagingaredemonstratedbyusinga2.52THzfarinfraredCO2laseranda320×240vanadiumoxidemicro-bolometerfocalplanearraywithanoptimizedcellstructure.Withthisdetectingsystem,THzimagingofmetalconcealedinawipingclothandanenvelopeisdemonstrated,respectively.

  • 标签: 微测辐射热计 太赫兹成像 焦平面阵列 探测器 设计 应用
  • 简介:Angularcoloruniformity(ACU)isakeyfactorusedtoevaluatethelightqualityofwhite-lightemittingdiodes(LEDs).Inthisstudy,anoveldoubleremotemicro-patternedphosphorfilm(doubleRMPPfilm)wasusedtoenhancetheACUofaremotephosphor(RP)down-lightlamp.AconventionalRPfilmandremotephosphorfilmwithsinglemicro-patternedfilm(singleRMPPfilm)alsowereexaminedforcomparison.Theangularcorrelatedcolortemperature(CCT)distributionsandtheopticalperformanceofthefilmswereexperimentallymeasured.ThemeasurementresultsshowedthatdoubleRMPPfilmconfigurationexhibitedbettercoloruniformitywithaCCTdeviationofonly441K,comparedwith556KforthesingleRMPPfilmconfigurationand1390KfortheRPfilmconfiguration.AsimulationbasedonFDTDandraytracingcombinedmethodalsoconfirmedtheACUimprovement.Inaddition,comparedwiththeconventionalRPfilm,theluminousefficiencyofsingleanddoubleRMPPfilmconfigurationswasincreasedby6.68%and4.69%,respectively,atadrivingcurrentof350mA.TheenhancementoftheACUandluminousefficiencyareduetothescatteringandmixingeffectofthemicropatternedfilm.Moreover,thedoubleRMPPfilmconfigurationhadbetterCCTstabilityatdifferentcurrentsthantheothertwoconfigurations.TheresultsdemonstratedtheeffectivenessandsuperiorityofdoubleRMPPfilminwhiteLEDapplications.

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