简介:Weinvestigatethedynamiccrystallizationprocessesofcolloidalphotoniccrystals,whicharepotentiallyinvaluableforsolvinganumberofexistingandemergingtechnicalproblemsinregardstocontrolledfabricationofcrystals,suchassizenormalization,stabilityimprovement,andaccelerationofsynthesis.Inthispaper,wereportsystematichigh-resolutionopticalobservationofthespontaneouscrystallizationofmonodispersepolystyrene(PS)micro-spheresinaqueoussolutionintoclose-packedarraysinastaticlineopticaltweezers.Theexperimentsdemonstratethatthecrystalstructureismainlyaffectedbytheminimumpotentialenergyofthesystem;however,thecrystallizationdynamicscouldbeaffectedbyvariousmechanical,physical,andgeometricfactors.Thecomplicateddynamictransformationprocessfrom1Dcrystallizationto2Dcrystallizationandthecreationandannihilationofdislocationsanddefectsviacrystalrelaxationareclearlyillustrated.Twomajorcrystalgrowthmodes,theepitaxygrowthpatternandtheinsertedgrowthpattern,havebeenidentifiedtoplayakeyroleinshapingthedynamicsofthe1Dand2Dcrystallizationprocess.Theseobservationsofferinvaluableinsightsforin-depthresearchaboutcolloidalcrystalcrystallization.
简介:U-shapedmicro-nanochannelscangeneratesignificantflowdisturbanceaswellaslocallyamplifiedelectricfield,whichgivesitselfpotentialtobemicrofluidicmixers,electrokineticpumps,andevencelllysisprocess.NumericalsimulationisutilizedinthisworktostudythehiddencharacteristicsoftheU-shapedmicro-nanochannelsystem,andtheeffectsofkeycontrollingparameters(theexternalvoltageandpressure)onthedeviceoutputmetrics(current,maximumvaluesofelectricfield,shearstressandflowvelocity)wereevaluated.Alargeportionofcurrentflowingthroughthewholesystemgoesthroughthenanochannels,ratherthanthemiddlepartofthemicrochannel,withitsvalueincreasinglinearlywiththeincreaseofvoltage.Duetothelocaliondepletionnearmicro-nanofluidicjunction,significantlyenhancedelectricfield(asmuchas15foldatV=1VandP0=0)aswellasstrongshearstress(leadingtoelectrokineticflow)isgenerated.Withincreasingexternalpressure,bothelectricfieldandshearstresscanbeincreasedinitially(duetoshorteningofdepletionregionlength),butaresuppressedeventuallyathigherpressureduetothedestructionofiondepletionlayer.Insightsgainedfromthisstudycouldbeusefulfordesigningnonlinearelectrokineticpumpsandothersystems.
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.
简介:Thepropertyofsiliconmicro-capacitiveaccelerometerisanalyzedanddiscussedbyestablishingthemodelofthesensor,tolayabasisforoptimizationdesignofsensorsystemstructure.Discussedissuesincludethestaticmodelinganddynamicbehaviorofthetwocommnlyusedstructures,i.e.,double-cantileversupportedandfour-beamsupportedstructures,andalsothemeasurementrangeofthesedevices.
简介:Theload-bearingcapacitiesofduclilecompositematerialsandstructuresarestudiedbymeansofacombinedmicro/macromechanicsapproach.Firstly,onthemicroscopicscale,theaimistogetthemacroscopicstrengthdomainsbymeansofthehomogenizationtheoryofmicromechanics.Arepresentativevolumeelement(RVE)isselectedtoreflectthemicrostructuresofthecompositematerials.Byintroducingthehomogenizationtheoryintothekinematiclimittheoremofplasticlimitanalysis,anoptimizationformaltodirectlycalculatethelimitloadsoftheRVEisobtained.Andthemacroscopicyieldcriterioncanbedeter-minedaccordingtotherelationbetweenmacroscopicandmicroscopicfields.Secondly,onthemacroscopicscale,byintroducingtheHill’syieldcriterionintothekinematiclimittheorem,thelimitloadsoforthotropicstructuressuchasunidirectionalfiber-reinforcedcompositestructuresareworkedout.Thefiniteelementmodelingofthekinematiclimitanalysisisdeducedintoanonlinearmathematicalprogrammingwithequality-constraintconditionsthatcanbesolvedbymeansofadirectiterativealgorithm.Finally,someexamplesareillustratedtoshowtheapplicationofthepresentapproach.
简介:Asiliconeacrylatemicro-emulsionofmultipolymerwaspreparedbyseedemulsionpolymerization.Theeffectsofpolymerizationprocess,emulsifierrateandamount,initiatorrateandamount,polymerizationtemperature,functionalmonomers,titrationtimeonperformancesofemulsionhavebeendiscussedindetail.
简介:AbstractThe human gastrointestinal tract accommodates an entire micro-environment for divergent physiologic processes, the dysbiosis of this micro-ecology has a strong inter-action with the pathogenesis of inflammatory bowel disease (IBD). In the past few years, with the advances in the understanding of microbiome, its metabolites and further application of next generation sequencing, analysis of dynamic alteration of gut micro-environment was realized, which provides numerous information beyond simple microbiota structure or metabolites differences under chronic colitis status. The subsequent intervention strategies targeting the modulation of intestinal micro-environment have been explored as a potential therapy. In this review, we will summarize the recent knowledge about multi-dimensional dysbiosis, the inter-action between fungus and bacteria under inflamed mucosa, and the clinical application of probiotics and fecal microbiota transplantation as a promising therapeutic approach in IBD.
简介:Fabricationofmicrogratingsusingafemtosecondlaserexposuresystemisexperimentallyinvestigatedfortheelectronmoirémethod.Microholesandlinesarefirstlyetchedforparameterstudy.Gratingprofileistheoreticallyoptimizedtoformhighqualitymoirépatterns.Forademonstration,aparallelgratingisfabricatedonaspecimenofquartzglass.Theminimumlinewidthandthedistancebetweentwoadjacentlinesarebothsettobe1μm,andthefrequencyofgratingis500lines/mm.Theexperimentalresultsindicatethatthequalityofgratingsisgoodandtherelativeerrorofthegratingspitchisabout1.5%.Basedonmoirémethod,scanningelectronmicroscope(SEM)moirépatternsareobservedclearly,whichmanifeststhatgratingsfabricatedwiththefemtosecondlaserexposureissuitableformicroscaledeformationmeasurement.
简介:※流明帮手2000流明帮手利用Windows操作系统提供您一个熟悉且容易使用的图形使用者接口。提供CAD接口一房间、对象(包括隔屏、桌子和椅子)与照明器具皆可使用鼠标作插入、移动、复制与删除之处理。三维立体检视画面提供您以卓越的视觉与设计操控能力,流明帮手循序渐进提示
简介:1IntroductionEarlyattemptstocreateasoundabsorberwhichwouldfunctionwithouttheinvolvementofanyfibrousorporousdampingmaterialgofarbacktoK.A.Veliszhanina,S.N.RschevkinandothersaswasoutlinedinRef.[1].30yearsago,D.Y.MAA[2]wasfirstinproposingapracticabledesignconceptandcalculationmodelforMicro-PerforatedAbsorber(MPA)prototypeswhichstillformsthebasisforvariousapplications.Duringthepast12yearstheFraunhoferIBP
简介:以便减少磨擦力量并且在低速度消除一个技工系统的粘住滑倒现象,一个方法基于超声的微开车技术被建议改变摩擦特征。顺时针方向激动并且在超声的致动器的二个纵的夹钳门栓的震荡器上驾驶点的逆时针方向的显微镜的椭圆的运动将产生超声的润滑油行动;而且,磨擦能被调整震荡器的颤动的振幅活跃地控制。为磨擦控制的试验性的安装用航空的指南,力量传感器和一低速度时刻被设计motor.Fuzzy控制理论被使用进这个系统。实验显示磨擦力量大部分被减少了,试验性的系统的运动是稳定的。当超声的致动器和负担is3.8kg和马达的全部的团正在开车时,磨擦系数仅仅是大约0.0053速度是0.5mm/s。