简介：高度强制的钴铁酸盐nanoparticles被他们的暂停的直接注射为加热为磁性的过高热综合并且学习进一个强壮的听觉频率的磁场的一个肿瘤和应用。物理(在液体和稳固的分散的动态磁性的磁滞现象和热产生)，生物(在进老鼠肿瘤织物的治疗学的数量的粒子的毒性和穿入)象其它一样，粒子的性质被学习。一个模型被开发为Brownian和常规旋转与一篇报道在磁性的nanoclusters的暂停描述magnetodynamics，到提供观察现象的理解。开发的试验性、理论的技术为低频率的热产生为磁性的nanoparticles的可控制的合成形成了一个基础在医药并且另外的应用程序。

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简介：Wepresentadesignmethodforcalculatingandoptimizingsoundabsorptioncoefficientofmulti-layeredporousfibrousmetals(PFM)inthelowfrequencyrange.PFMissimplifiedasanequivalentidealizedsheetwithallmetallicfibersalignedinonedirectionanddistributedinperiodichexagonalpatterns.Weuseaphenomenologicalmodelintheliteraturetoinvestigatetheeffectsofporegeometricalparameters(fiberdiameterandgap)onsoundabsorptionperformance.ThesoundabsorptioncoefficientofmultilayeredPFMsiscalculatedusingimpedancetranslationtheorem.Todemonstratethevalidityofthepresentmodel,wecomparethepredictedresultswiththeexperimentaldata.Withtheaveragesoundabsorption(lowfrequencyrange)astheobjectivefunctionandthefibergapsasthedesignvariables,anoptimizationmethodformulti-layeredfibrousmetalsisproposed.Anewfibrouslayoutwithgivenporosityofmulti-layeredfibrousmetalsissuggestedtoachieveoptimallowfrequencysoundabsorption.Thesoundabsorptioncoefficientoftheoptimalmulti-layeredfibrousmetalishigherthanthesinglelayeredfibrousmetal,andasignificanteffectofthefibrousmaterialonsoundabsorptionisfoundduetothesurfaceporosityofthemulti-layeredfibrous.

简介：这份报纸在一个交流磁场与磁性的磁滞现象和机械活动性在小铁磁性的粒子的暂停在magnetodynamics和精力驱散上论述理论、试验性的研究。由在固体，液体或煤气的环境推迟并且使遭到了到高频率磁场的粒子的精力吸收具有为由过高热，化学技术，生物工学和聪明的材料科学的癌症治疗的大兴趣。在液体驱散的亚微米像针的-Fe2O3粒子与多达105A/m的紧张在这研究受到430Hz磁场。动态磁化环在平行被测量到在样品浪费的体力。粒子分散的联合magnetomechanical动力学被使用允许的一个chain-of-spheres模型模仿支离破碎的磁场颠倒。在液体分散，在千赫频率范围以内，粒子的机械活动性不防碍他们使热版本可比较到那的磁性的颠倒与固体观察了的hysteretic；例如，在用-Fe2O3的现在的学习，在液体的粒子使遭到了到展出的热版本每干燥粒子内容的1cm3从250评估直到600W的104Hz地。

简介：Heattransportisakeyenergeticprocessinmaterialsanddevices.Thereducedsamplesize,lowdimensionoftheproblemandtherichspectrumofmaterialimperfectionsintroducefruitfulphenomenaatnanoscale.Inthisreview,wesummarizerecentprogressesintheunderstandingofheattransportprocessinlow-dimensionalmaterials,withfocusontherolesofdefects,disorder,interfaces,andthequantummechanicaleffect.Newphysicsuncoveredfromcomputationalsimulations,experimentalstudies,andpredictablemodelswillbereviewed,followedbyaperspectiveonopenchallenges.

简介：Thispapergivesanoverviewonnonlinearporousflowinlowpermeabilityporousmedia,revealsthemicroscopicmechanismsofflows,andclarifiespropertiesofporousflowfluids.Itshowsthat,deviatingfromDarcy’slinearlaw,theporousflowcharacteristicsobeyanonlinearlawinalow-permeabilityporousmedium,andtheviscosityoftheporousflowfluidandthepermeabilityvaluesofwaterandoilarenotconstants.Basedonthesecharacters,anewporousflowmodel,whichcanbetterdescribelowpermeabilityreservoir,isestablished.Thismodelcandescribevariouspatternsofporousflow,asDarcy’slinearlawdoes.Alltheparametersinvolvedinthemodel,havingdefinitephysicalmeanings,canbeobtaineddirectlyfromtheexperiments.

简介：TheaerodynamicforcesandflowstructureofamodelinsectwingisstudiedbysolvingtheNavier-Stokesequationsnumerically.Afteraninitialstartfromrest,thewingismadetoexecuteanazimuthalrotation(sweeping)atalargeangleofattackandconstantangularvelocity.TheReynoldsnumber(Re)consideredinthepresentnoteis480(Reisbasedonthemeanchordlengthofthewingandthespeedat60%winglengthfromthewingroot).Duringtheconstant-speedsweepingmotion,thestallisabsentandlargeandapproximatelyconstantliftanddragcoefficientscanbemaintained.Themechanismfortheabsenceofthestallorthemaintenanceoflargeaerodynamicforcecoefficientsisasfollows.Soonaftertheinitialstart,avortexring,whichconsistsoftheleading-edgevortex(LEV),thestartingvortex,andthetwowing-tipvortices,isformedinthewakeofthewing.Duringthesubsequentmotionofthewing,abase-to-tipspanwiseflowconvertsthevorticityintheLEVtothewingtipandtheLEVkeepsanapproximatelyconstantstrength.ThispreventstheLEVfromshedding.Asaresult,thesizeofthevortexringincreasesapproximatelylinearlywithtime,resultinginanapproximatelyconstanttimerateofthefirstmomentofvorticity,orapproximatelyconstantliftanddragcoefficients.Thevariationoftherelativevelocityalongthewingspancausesapressuregradientalongthewingspan.Thebase-to-tipspanwiseflowismainlymaintainedbythepressure-gradientforce.

简介：Inthispaper,theinfluenceofvariousboundaryconditionsonthefrequencyresponseofthreelayeredplatesisanalysedusinghigherordertheoryofsheardeformation.ThefacesheetsarelaminatedorthotropiccompositebasedonMindlintheory(orFSDT).UtilisingmethodofenergyandprincipleofHamilton,theequationsofmotionareobtainedconsideringcontinuityboundaryconditionsbetweenlayers.Themodeshapesandfrequencyoftheplatearecalculatedapplyingmethodofdifferentialquadrature(DQM).

简介：TheeffectoffrequencyandsampleshapeonfatiguebehaviorsofDZ125superalloyaresystematicallystudied.Theresultsshowthatfatiguefracturestilloccursabovethecycleof10~8fortestscarriedoutatthefrequencyoff=20kHzandstressratioR=-1,sothetraditionalfatiguelimitatcycleof10~7isnotappropriateforfatiguedesign.Fatiguefracturesurfacesareperpendiculartostressaxisforcylindricalandplatespecimens,andthefatiguecracksoriginatefromtheextrasurfaceofthespecimens.Fatiguecrackisapttopropagatefromcuttingdirectiontoforwarddirection,whichoccursmainlyinthesecondpropagationstageathigherstressamplitude.ThereisanobviousfrequencyeffectforDZ125superalloy.Thehigherthetestfrequencyis,themoreserioustheeffectoffrequencyonfatiguebehaviorsofthealloy.Afterthefrequencycorrection,theultra-highcyclefatigueS-NcurvewellcoincidewiththetraditionalfatigueS-Ncurve.

简介：Coherentstructuresareessentialforthemomentumexchangeandturbulenceproductioninwall-boundedturbulentflows.Diversifiedcoherentstructureshavebeenobservedinturbulentboundarylayers,andhairpin-basedvorticesdominatemostoftherelevantliterature.However,thereisnoconsensusyetontheoriginandformingmechanismofhairpinvortices.Herein,fivecornerstonespertainingtotheframeworkofhairpin-basedcoherentstructuresarereviewed,andthreedifferenthairpingenerationmechanismsareclarified.Next,thetime-resolvedtomographicparticleimagevelocimetry(Tomo-PIV)isusedinanearlyturbulentboundarylayer(Reθ=420)toinvestigatetheoriginofhairpinvortices.Thetimelinesrevealatriangularbulgeinthelow-speedstreak(LSS),andtheinitialroll-upoccursattwosidesofit.Meanwhile,thematerialsurfacesmanifestasathree-dimensional(3D)wavestructureintheLSS,whichmaysupportthemodelofasoliton-likecoherentstructure(SCS).Subsequently,themethodofLagrangian-averagedvorticitydeviationisusedtodetectearlyvortices.Wefindthatthe3Dwavestructureisflankedbytwovortices,thusconfirmingtheroll-upoftimelinesanddemonstratingtheadvantageoftheLagrangiancriteriaincapturingstructuresincomplexflows.Theseresultssuggestthatvariouscoherentstructuresmayevolvefromthemetamorphosisof3Dwavestructuresandtheirlaterinteraction.Finally,thelimitationsoftraditionalexperimentalandpost-processingtoolsarediscussed.

简介：Thepolarlowandtropicalcyclonetypevorticesovertopographyareassumedtobetheaxisymmetricalandthermal-windbalancedsystems,whicharesolvedasaninitialvalueproblemofalinearizedvortexequationsetincylindricalcoordinates.Therolesofthesensibleandlatentheating,friction,andtopographyinthestructureandintensificationofthepolarlowandtropicalcyclonetypevorticesareanalyzed.Theradialvelocity,verticalvelocity,azimuthalvelocity,andtheunstablegrowthrateincludingthetopographyeffectsareobtained.Itisshownthattheinteractionbetweentheflowandthetopographyplaysasignificantroleinthestructureandintensificationofthepolarlowandtropicalcyclonesystem.Theanalysisofthetopographytermindicatesthat,intheup-slopesideofthemountain,theradialinflowandtheverticalascentforcedbythemountaincanintensifythepolarlowandtropicalcyclonetypevortexandincreasetheunstablegrowthrate.However,intheleesideofthemountain,theradialinflowandtheverticaldescentforcedbythemountaincanweakenthepolarlowandtropicalcyclonetypevortexanddecreasetheunstablegrowthrateofthepolarlowandtropicalcyclonesystem.Inaddition,theevolutionaryprocessandthespatialstructureofthepolarlowobservedovertheJapanSeaon19December2003areinvestigatedwiththeobservationaldatatoverifythistheoreticalresult.

简介：Spacecraftsciencemissionstoplanetsorasteroidshavehistoricallyvisitedonlyoneorseveralcelestialbodiespermission.Theresearchgoalofthispaperistocreateatrajectorydesignalgorithmthatgeneratestrajectoryallowingaspacecrafttovisitasignificantnumberofasteroidsduringasinglemission.Fortheproblemofglobaltrajectoryoptimization,evenwithrecentadvancesinlow-thrusttrajectoryoptimization,afullenumerationofthisproblemisnotpossible.Thisworkpresentsanalgorith...

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简介：Alow-diffusionpreconditioningRoeschemewithanadjustableparametertocontrolthenumericaldissipationisproposed.Thisschemereflectstherealphysicaldissipationintheextremelylow-speedregion.Thepreconditioningparameterinschemeisimprovedbylinearcut-offandcorrectionfactor.Thenumericalresultsoflow-Mach-number/low-Reynolds-numbersteadysolutionsofviscousflowspastacircularcylinderandpastaNACA0012airfoilshowtheefficiencyofthenewscheme.

简介：TheproblemofcheckingrobustD-stabilityofmulti-inandmulti-out(MIMO)systemswasstudied.Threesystemmodelswereintroduced,i.e.multilinearpolynomialmatrix,polytopicpolynomialmatrixandfeedbacksystemmodel.Furthermore,theconvexpropertyofeachmodelwithrespecttotheparametricuncertaintieswasestablishedrespectively.Basedonthis,sufficientconditionsforD-stabilitywereexpressedintermsoflinearmatrixinequalities(LMIs)involvingonlytheconvexvertices.Therefore,therobustD-stabilitywastestedbysolvinganLMIoptimalproblem.

简介：首先，有不同坚硬的粒子的低速度的传送的特征试验性地以流动模式和压力落下在一条水平管道被调查证明蛞蝓流动能被分类进取决于沿着管道安定粒子的二种类型，并且没有解决的层，时期为蛞蝓流动是小的，它被叫独居的蛞蝓流动。为软粒子的压力落下被显示为难粒子比那大。然后，试验性的结果在证明从传送隧道的最高的表面的那个空气版本是为粒子的高集体的流动率的一个重要因素的好粉末的水平使流体化床的传送上被介绍。

简介：Theconstitutiveequationunderthelow-cyclefatigue(LCF)wasdiscussed,andatwo-dimensional(2-D)modelforsimulatingfatiguecrackextensionwasputforwardinordertoproposeanewcyclicJ-integral.Thedefinition,primarycharacteristics,physicalinterpretationsandnumericalevaluationofthenewparameterwereinvestigatedindetail.Moreover,thenewcyclicJ-integralforLCFbehaviorswasvalidatedbythecompacttension(CT)specimens.ResultsshowthatthecalculatedvaluesofthenewparametercancorrelatewellwithLCFcrackgrowthrate,duringconstant-amplitudeloading.Inaddition,thephenomenonoffatigueretardationwasexplainedthroughtheviewpointofenergybasedontheconceptofthenewparameter.

简介：在骨头的Microdamage累积在破裂过程期间是为精力驱散的机制之一。在骨头成分的超微结构和作文的变化能由于老化或疾病影响microdamage累积。钠氟化物(NaF)的低集中(1mM)在这研究被使用了在跟随免费秋天的影响装载的老鼠胫骨在microdamage累积上调查ultrastructural变化的效果。22根胫骨随机被划分成控制和对待NaF的组。装载的免费秋天的影响在每根胫骨上被进行两次生产microdamage。对待NaF的胫骨的有弹性的模量在影响装载以后显著地减少了，当在未经治疗的样品在之间的模量没有重要差别时预先损坏并且损坏以后的装载。Microdamage形态学分析少些显示出那，更短的microcracks与控制骨头相比在对待NaF的胫骨存在。同时，更多和更长的microcracks在压缩区域与那相比在未经治疗的样品在张力的区域被观察，而没有重要差别在对待NaF的骨头在张力、压缩的区域之间被观察。这研究的结果显示更多的精力被要求比在正常骨头在对待NaF的骨头产生microcracks。氟化物处理的低集中可以在装载的影响下面增加骨头的坚韧。这研究在ultrastructural的效果上集中了的图形的摘要在影响装载下面在骨头在microdamage上变化。对待NaF的胫骨的有弹性的模量在影响装载以后显著地减少了。更少和更短的microcracks在对待NaF的胫骨骨头存在。更多的精力被要求在对待NaF的骨头产生microdamage。氟化物处理的低集中可以增加骨头的坚韧。

简介：Carbon-manganesesteelisoftenappliedincomponentsofpipesinnuclearplant.Ultrasonicfatiguetestsfollowinglowcyclefatigue(LCF)cyclesdamagedareusedtostudythestrengthofveryhighcyclefatigure(VHCF).ThecomparisonoftestresultsofsimpleVHCFandcumulativefatigue(LCFplusVHCF)showsthatLCFloadinfluencesthefollowingVHCFstrength.ContinuumdamagemechanicsmodelisextendedtoVHCFregion.TheeffectofLCFloadonVHCFisstudiedbyanimprovedcumulativedamagemodel.

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