简介：Acceleratingtheconvergencespeedandavoidingthelocaloptimalsolutionaretwomaingoalsofparticleswarmoptimization(PSO).TheverybasicPSOmodelandsomevariantsofPSOdonotconsidertheenhancementoftheexplorativecapabilityofeachparticle.Thusthesemethodshaveaslowconvergencespeedandmaytrapintoalocaloptimalsolution.Toenhancetheexplorativecapabilityofparticles,aschemecalledexplorativecapabilityenhancementinPSO(ECE-PSO)isproposedbyintroducingsomevirtualparticlesinrandomdirectionswithrandomamplitude.Thelinearlydecreasingmethodrelatedtothemaximumiterationandthenonlinearlydecreasingmethodrelatedtothefitnessvalueofthegloballybestparticleareemployedtoproducevirtualparticles.TheabovetwomethodsarethoroughlycomparedwithfourrepresentativeadvancedPSOvariantsoneightunimodalandmultimodalbenchmarkproblems.ExperimentalresultsindicatethattheconvergencespeedandsolutionqualityofECE-PSOoutperformthestate-of-the-artPSOvariants.

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简介：Icewatercontent(IWC)playsimportantrolesinweatherandclimatechange.DeterminingtheIWCsofcirruscloudswithmillimeter-wavelengthradarcanbeproblematicduetoinfluencesoficeparticlerotationontheirbackscatteringcrosssections.Wehereintroducemodelstodescribetheradiationpatternsofsixnonsphericalparticlesofspecificsizes.SimulationsusingHFSSsoftwarewereappliedtodescribethedifferencesresultingfromdifferentorientationsandequivalentspheres.Adoubleexponentialfunctionwasusedforfittingtodescribetherelationshipbetweentheparticles’maximumsizesandbackscatteringcrosssections.Thebackscatteringcrosssectionsofnonsphericaliceparticleswerecomputedbythemethodofmoment,andthoseoftheequivalentsphericalparticleswerecomputedbyLorenz-Mietheoryforthreedifferentorientations:fixed,horizontal,andrandom.AssumingthatamixtureofnonsphericaliceparticlesfollowstheB-Hmixingmodel,thesizedistributionofcirrusparticlesobeystheexponentialdistributionmeasuredbyNASAin2007.BycomputingtheIWCsofcirrusclouds,whichfollowstheabovementionedB-Hmodelandexponentialdistribution,theradarreflectivityfactorsofnonsphericaliceparticlesandequivalentspheresatthreedifferentorientationscanbecomputed.Subsequently,theIWCresultscanbeacquiredbyinputtingtheradarreflectivityvariablesintothewell-knownIWC-Zformula.TheanalysisdescribedheredemonstratesthatwhenusingtheradarreflectivityZ,theorientationmustbeconsideredinordertodeterminetheIWC.Usingequivalentspheretheory,thederivedIWCsunderestimatetheactualIWCs.Theseresultsareimportantforaccuratelyretrievingthemicrophysicalparametersofcirrusclouds.

简介：包括毛状的力量和毛状的吸，毛状的相互作用在有固定液体体积的二个不相等尺寸的粒子之间被调查。毛状的相互作用模型在Young-Laplace框架以内被使用。与液体桥，毛状的吸，和象州的变量的液体卷的顶点的侧面，有二定点的边界的管理方程首先用一种可变替换技术，严肃效果在被忽视被导出。有固定体积的液体桥的毛状的吸和几何学与一个射击方法被解决。在为毛状的力量建模，峡方法被使用。包括在二个粒子，粒子半径的比率，和液体固体之间的距离的各种各样的参数的效果联系角度被讨论。

简介：Twofamiliesofcatalysts,basedonPdnanoparticlessupportedonceramicasymmetrictubularaluminamembranes,arestudiesinthedirectsynthesisofH_2O_2.TheyarepreparedbydepositingPdintwoways:(i)reductionwithN_2H_4inanultrasonicbathand(ii)byimpregnation-deposition.Thefirstpreparationleadstolargerparticles,withaveragesizeofaround11nm,whilethesecondpreparationleadstosmallerparticles,withaveragesizearound4nm.Thecatalyticmembranesweretestedasprepared,afterthermaltreatmentinairandafterfurtherpre-reductionwithH_2inmild(100℃)conditions.SampleswerecharacterizedbyTEM,CO-chemisorptionmonitoredbyDRIFTSmethodandTPR,whilecatalytictestshavebeenperformedinasemi-batchrecirculationmembranereactor.Experimentalcatalyticresultswereanalysedusingtwokineticsmodelstoderivethereactionconstantsfortheparallelandconsecutivereactionsofthekineticnetwork.SmallerparticlesofPdshowlowerselectivityduetothehigherrateofparallelcombustion,evenifthebetterdispersionofPdandthushighermetalsurfaceareainthesampleleadtoaproductivityinH_2O_2similarorevenhigherthanthesamplewiththelargerPdparticles.IndependentlyonthepresenceofsmallerorlargerPdnanoparticles,anoxidationtreatmentleadstoasignificantenhancementintheproductivity,althoughthecatalystprogressivelyreducesduringthecatalyticprocess.Theinhibitionoftheparallelcombustionreaction(towater)inducedfromthecalcinationtreatmentremainsafterthein-situreductionoftheoxidizedPdspeciesformedduringthepre-treatment.Thisislikelyduetotheeliminationofdefectsiteswhichdissociativelyactivateoxygen,andtentativelyattributedtoPdsitesabletogivethree-andfour-foldcoordinationofCO.

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。

简介：Byinvestigatingthecross-spectraldensityofpartiallycoherentmulti-rotatingellipticalGaussianbeams(REGBs)thatpropagatethroughafocusingopticalsystem,weobtaintheradiationforceonaRayleighparticle.Theradiationforcedistributionisstudiedunderdifferentbeamindexes,coherencewidths,andellipticalratiosofthepartiallycoherentmultiREGBs.Thetransverseandthelongitudinaltrappingrangescanincreaseatthefocalplanebyincreasingthebeamindexordecreasingthecoherencewidth.Therangeofthetrappedparticleradiiincreasesastheellipticalratioincreases.Furthermore,weanalyzethetrappingstability.

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简介：Tadpole-shapedAunano-particleswithcontrollabletailsaresuccessfullyfabricatedbysimplyusinglaserfragmentationofseparatedAunano-spheresinliquid.Theoptimumlaserpowerdensities(1.5–3GW∕cm~2)canenablepartoftheindividualAunano-spheretobere-melted,released,andultra-rapidlyrecondensed/crystallizedontheoutsideoftheoriginalregion.Wefindthatthelengthofthetailinatadpole-shapedAunano-particlesignificantlyincreasesfromabout10to25nmbyincreasingthelaserpowerdensity.Benefitingfromtheuniquestructuralfeatures,thelocalizedsurfaceplasmonresonance(LSPR)absorptionspectraofthetadpole-shapedAunano-particlesbecomebroaderbyincreasingthetaillength.Moreover,theLSPRabsorptionbandalsoexhibitsanoticeableredshiftfromabout520to650nm.Ourresultsprovideaconvenientandvaluablestrategytofabricatednovelanisotropic-shapednano-structureswithfascinatingproperties.

简介：纸从superhydrophobic模板和superhydrophilic底层的联合效果由三明治结构为像杆的硅石粒子的面向的汇编表明了一条灵巧的途径。像杆的粒子能被安排在似环，像平方并且等等从限制了模板的效果，它将为各向异性的粒子的面向的汇编和新奇功能的材料和设备的开发生产重要卓见。

简介：空CuO-CeO2-ZrO2nano粒子被作为反溶剂把甲醇用作溶剂和supercritical二氧化碳与supercritical反溶剂仪器准备。二个关键因素(即，压力和温度)被调查探索催化剂结构和药品化学药品性质的效果(即，形态学，减少的性质，氧存储能力和特定的表面区域)。产生材料与X光检查衍射(XRD)被描绘，高决定传播电子显微镜学(HRTEM)，Brunauer-Emmett-Teller(赌注)，氢温度规划了减小(H2-TPR)和氧存储能力(振荡)测量分别地。试验性的结果证明更低的温度支持了空结构nano微粒的生产。粒子形态学也显著地变化了，即稳固的构造然后首先被转移到空结构回到稳固的建设。为获得空nano粒子的最佳的条件在45点被决定

简介：Amethodtothree-dimensionalpositionmovingparticleswithonelensandtwocamerasisproposed.Twoparticleimageswithdifferentdegreesofdefocusingareadoptedtosolvetheambiguousproblemofparticlepositions.Asingle-lensdual-camerasystemisdevelopedtosimultaneouslycapturethesetwoimagesforthemovingparticles.Themeasurementprinciplesandtheoreticalanalysisareintroducedfirst,andthensimulatedinvestigationsandexperimentalresearcharediscussed.Themeasurementerrorsinthesimulationsandexperimentsarelessthan1%and4%,respectively,in20timesthedepthoffieldofthesystem,whichvalidatesthefeasibilityofthismethod.