简介：

简介：连结积极反馈环，生物化学的系统的一块重要积木，能导致双稳态的切换，导致长持续的状态由简短刺激变化。在这个工作，在二种之间的流行相互的激活作为另一积极反馈被加到从许多现实主义的生物电路发源的一个通用连结positive-feedback-loop模型。积极反馈力量的一个随机的变化在反馈力量的双稳态的间隔被介绍，并且bistability在某个噪音水平为中等反馈力量出现。稳定性分析进一步基于势能风景被利用探索二个稳定的稳定的状态的导致噪音的切换行为。

简介：Assumingthatthelithiationreactionoccursrandomlyinindividualsmallparticlesinthevicinityofthereactionfront,asimplemodelofdiffusioninduceddislocationswasdeveloped.Thediffusion-induceddislocationsarecontrolledbythemisfitstraincreatedbythediffusionofsoluteatomsorthephasetransformationinthevicinityofthereactionfront.Thedislocationdensityisproportionaltothetotalsurfaceareaofthe"lithiatedparticle"andinverselyproportionaltotheparticlevolume.Thediffusion-induceddislocationsrelievethediffusion-inducedstresses.

简介：Thestress-inducedmagneticdomainswitchinginFeGathinfilmsisstudiedusingphase-fieldmethod.Inparticular,themagneticfieldisappliedalongthe[110]directionandbiaxialstressesareappliedalong[100]and[010].Acompressivepre-stresscorrespondstoasmallercoercivemagneticfieldwhileatensilepre-stresscorrespondedtoalargercoercivefield.Atthesametime,itisalsofoundthatthetransitionbetweenbutterflyandsquare-likemagnetostrictionloopsoccursatthecriticaloppositebiaxialstressstate.Thetwodifferentevolutionscorrespondtotwodifferentmechanisms:oneisthatthesingledomainswingsacrossafanareabackandforth;theotheristhatthesingledomainturnsaclockwisecircle.Theresultscanbeexplainedbythestresstunedanisotropyenergywell.

简介：连贯的多角形的粒子的二维的分离元素模型(DEM)模拟被开发了估计点来源颤动的利益在楔形的hoppers导致流动。使用的particleparticle相互作用模型基于一个多接触原则。没有颤动，学习的第一部分在严肃下面调查了粒子分泌物决定批评的孔尺寸(Bc)就作为粒子形状的功能支撑流动。多角形形状的粒子比圆形的粒子需要一个更大的孔，这被显示出。当粒子顶点的数字增加，Bc减少，这也被显示出当粒子顶点的数字增加。圆形的粒子的增加以一种线性方式支持多角形的流动。学习的第二部分证明那颤动能提高流动，有效地减少Bc。模型表明了震荡器地点(高度)的重要性，与在提高的以前的连续统模型结果，和颤动振幅一致流动。

简介：Thediffusionbehaviordrivenbyboundednoiseundertheinfluenceofacoupledharmonicpotentialisinvestigatedinatwo-dimensionalcoupled-dampedmodel.WiththehelpoftheLaplaceanalysisweobtainexactdescriptionsforaparticle’stwo-timedynamicswhichissubjectedtoacoupledharmonicpotentialandacoupleddamping.Thetimelagisusedtodescribethevelocityautocorrelationfunctionandmeansquaredisplacementofthediffusingparticle.Thediffusionbehaviorforthetimelagisalsodiscussedwithrespecttothecoupleditemsandtheamplitudeofboundednoise.

简介：DetaileddistributionsofheatfluxintheregionofshockwaveandturbulentboundarylayerinteractioninducedbyacylinderweremeasuredintheshocktunnelOilflowpatternsandSchlierenphoto-graphsweretaken.Empiricalrelationsweregivenfordeterminingseparationshockangle,peaksofheatfluxandtheirlocationsonbothcylinderleadingedgeandflatplatesurface,andothercharacteristicparametersoftheinteractionregion.

简介：Anenergyapproachisproposedtodescribetheelectromigrationinducedgrainrotationunderhighcurrentdensity.Thedrivingforceisassumedtoarisefromthegrain-boundaryenergyreductionandincreaseoftheinnerenergyfromthejouleheating.Energydissipatesbythegrainboundarydiffusionunderelectromigrationandviscousboundaryslidingisconsidered.Basedontheconservationofenergyproductionanddissipation,anequilibriumequationisdevelopedtopredictthegrainrotationrateanalytically.Itisrecognizedthatthegrainrotateswiththereducingofelectricalresistivityandinverselyproportionaltothegrainlength.Thetheoreticalpredictioniscomparedwiththeexperimentaldata,whichshowsgoodaccuracyontherotationtrendandthespecificrotationrate.

简介：以便改进导致双胞胎的粘性钢的机械性质，谷物形态学被技术与处理线路的变丑和热处理相结合的不同团结定制。三典型谷物形态学，即，equiaxed，象equiaxed/columnar谷物一样圆柱被形成，并且他们的机械行为比较地被学习。在三材料之中，equiaxed谷物材料展出了最高的力量但是最低粘性。取决于谷物尺寸，越小谷物尺寸，越higher力量，但是更低延伸。圆柱的谷物材料拥有了最优秀的粘性但是最弱的力量。介绍的这些性质一非单调?树突间距上的依赖，和中等间距导致了力量和粘性的最佳联合。equiaxed/columnar谷物共存了材料显示出有趣的性质，即，力量和粘性只在单个塑造谷物的材料的那些之间。特别地在一致变丑的也介绍的不同紧张变硬行为上演的三材料。equiaxed谷物材料显示出变硬的经常的紧张评价，当圆柱的谷物和equiaxed/columnar谷物材料与增加真紧张显示出日益增多地增加的率时。

简介：Wepresentsecond-orderexpressionsforthefree-surfaceelevation,velocitypotentialandpressureresultingfromtheinteractionofsurfacewavesinwaterofarbitrarydepth.Whenthesurfacewaveshavenearlyequalfrequenciesandnearlyoppositedirections,asecond-orderpressurecanbefeltallthewaytotheseabottom.Thereareatleasttwoareasofapplications:reflectivestructuresandmicroseisms.Microseismsgeneratedbywaterwavesintheoceanaresmallvibrationsofthegroundresultingfrompressureoscillationsassociatedwiththecouplingofoceansurfacegravitywavesandtheseafloor.Theyarerecordedonland-basedseismicstationsthroughouttheworldandtheyaredividedintoprimaryandsecondarytypes,asafunctionofspectralcontent.Secondarymicroseismsaregeneratedbytheinteractionofsurfacewaveswithnearlyequalfrequenciesandnearlyoppositedirections.Theefficiencyofmicroseismgenerationthusdependsinpartonoceanwavefrequencyanddirection.Basedonthesecond-orderexpressionsforthedynamicpressure,asimpletheoreticalanalysisthatquantifiesthedegreeofnearnessinamplitude,frequency,andincidenceangle,whichmustbereachedtoobservethephenomenon,ispresented.

简介：Lagrangian-Eulerianformulationsbasedonageneralizedvariationalprincipleoffluid-solidcouplingdynamicsareestablishedtodescribeflow-inducedvibrationofastructureundersmalldeformationinanincompressibleviscousfluidflow.Thespatialdiscretizationoftheformulationsisbasedonthemulti-linearinterpolatingfunctionsbyusingthefiniteelementmethodforboththefluidandsolidstructures.Thegeneralizedtrapezoidalruleisusedtoobtainapparentlynon-symmetriclinearequationsinanincrementalformforthevariablesoftheflowandvibration.Thenonlinearconvectivetermandtimefactorsarecontainedinthenon-symmetriccoefficientmatrixoftheequations.Thegeneralizedminimumresidual(GMRES)methodisusedtosolvetheincrementalequations.AnewstablealgorithmofGMRES-Hughes-Newmarkisdevelopedtodealwiththeflow-inducedvibrationwithdynamicalfluid-structureinteractionincomplexgeometries.Goodagreementbetweenthesimulationsandlaboratorymeasurementsofthepressureandbladevibrationaccelerationsinahydroturbinepassagewasobtained,indicatingthattheGMRES-Hughes-Newmarkalgorithmpresentedinthispaperissuitablefordealingwiththeflow-inducedvibrationofstructuresundersmalldeformation.

简介：机械脱落是一个广泛地使用的方法从体积石墨孤立高质量的graphene层。在我们的最近的实验，一些订了微观结构，由性变态和条纹的周期的引申组成，在薄石墨薄片被观察机械地从高度面向的pyrolytic被剥石墨。在这份报纸，一个理论模型被介绍在脱落期间把如此的订的结构的形成归因于二个机械过程的引申：(1)一个石墨薄片脱皮并且(2)薄片的机械弄弯正在受到弯曲。在这个模型，条纹L的宽度被薄片，表面精力\(\gamma\)，和批评弄弯紧张\的厚度h决定(\varepsilon_{\mathrm{cr}}\)。用\(\gamma\)和\的一些适当价值(\varepsilon_{\mathrm{cr}}\)那在另外的独立实验和模拟决定的范围以内，在条纹宽度之间的预言的关系和薄片厚度与我们的试验性的大小相当同意很好。相反地，在薄石墨薄片测量周期的微观结构的Lh关系能帮助决定批评机械弄弯紧张\(\varepsilon_{\mathrm{cr}}\)并且接口精力\(\gamma\)。

简介：

简介：Thepaperstudiestheproblemoffluidflowandfluidshearstressincanaliculiwhentheosteonissubjecttoexternalmechanicalloadingandbloodpressureoscillation.Thesingleosteonismodeledasasaturatedporoelasticcylinder.Solidskeletonisregardedasaporoelastictransverselyisotropicmaterial.Togetnear-realisticresults,boththeinterstitialfluidandthesolidmatrixareregardedascompressible.BloodpressureoscillationintheHaveriancanalisconsidered.Usingtheporoelasticitytheory,ananalyticalsolutionoftheporefluidpressureisobtained.Assumingthefluidincanaliculiisincompressible,analyticalsolutionsoffluidflowvelocityandfluidshearstresswiththeNavier-Stokesequationsofincompressiblefluidareobtained.Theeffectofvariousparametersonthefluidflowvelocityandfluidshearstressisstudied.更多还原

简介：Thepresentpaperdescribesanumericaltwo-waycouplingmodelforshock-inducedlaminarboundary-layerflowsofadust-ladengasandstudiesthetransversemigrationoffineparticlesundertheactionofSaffmanliftforce.ThegoverningequationsareformulatedinthedilutetwophasecontinuumframeworkwithconsiderationofthefinitenessoftheparticleReynoldsandKnudsennumbers.ThefullLagrangianmethodisexploredforcalculatingthedispersedphaseflowfields(includingthenumberdensityofparticles)intheregionsofintersectingparticletrajectories.Thecomputationresultsshowasignificantreactionoftheparticlesonthetwo-phaseboundary-layerstructurewhenthemassloadingratioofparticlestakesfinitevalues.

简介：ＴＨＥＡＮＡＬＹＴＩＣＡＬＳＴＵＤＹＯＮＴＨＥＬＡＳＥＲＩＮＤＵＣＥＤＲＥＶＥＲＳＥ－ＰＬＵＧＧＩＮＧＥＦＦＥＣＴＢＹＵＳＩＮＧＴＨＥＣＬＡＳＳＩＣＡＬＥＬＡＳＴＩＣＰＬＡＴＥＴＨＥＯＲＹ（Ⅰ）－ＴＥＭＰＥＲＡＴＵＲＥＦＩＥＬＤＳＺｈｏｕＹｉｃｈｕｎ...

简介：Ultra-puremesoporoussilicamicrosphereswithgoodmonodispersityweresynthesizedintwosteps:nanometer-sizedsilicasolwasproducedbythesol-gelprocess,thenmicrometer-sizedsilicamicrospheresweresynthesizedbypolymerization-inducedcolloidaggregationofthesilicasol.Thetotalmetalcontentofthemicrosphereswasextremelylow,whicheliminatedthetailingofchromatographicpeaksbychelatingreagents.Theporestructureofthesilicamicrospherescouldbecontrolledbyalteringthesol-gelconditions.Thesilicamicrosphereparticlesizecouldbeadjustedbyusingdifferentpolymerizationinducedcolloidaggregationconditions.