简介：Carbonnanotubemacro-filmsaretwo-dimensionalfilmswithmicrometerthicknessandcentimeterbycentimeterin-planedimension.Thesecarbonnanotubemacroscopicassemblieshaveattractedsignificantattentionfromthematerialandmechanicscommunitiesrecentlybecausetheycanbeeasilyhandledandtailoredtomeetspecificengineeringneeds.Thispaperreportstheexperimentalmethodsonthepreparationandcharacterizationofsingle-walledcarbonnanotubemacro-films,andastatisticalmechanicsmodelon...

简介：最近的数字模拟显示了在cellsubstrate粘附期间聚类的integrin能被在房间膜和底层之间的排斥的层的存在驾驶(Paszek等，PLoSComputBiol5:12，2009)。这里我们在场在integrins之间的吸引力被膜和排斥的层的远程的有弹性的变丑在调停的这现象的一个简单力学模型。我们由采用在一个有弹性的基础上休息的一个无穷地扩大的盘子的小变丑理论获得分析答案到这个问题。

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简介：Duringtheonsetofadiseaseacellmayexperiencealterationsinboththecompositionandorganizationofitscellularandmolecularstructures.Thesealterationsmayeventuallyleadtochangesinitsgeometricalandmechanicalpropertiessuchascellsizeandshape,deformabilityandadhesion.Assuch,knowinghowdiseasedcellsrespondtomechanicalforcescanrevealwaysbywhichtheydifferfromhealthyones.Here,wewillpresentbiomechanisticinsightsintoredbloodcellrelateddiseasesthatmanifest...

简介：Usingthetechniqueofintegralwithinanorderedproduct(IWOP)ofoperatorsweshowthatthewavelettransformcanberecastedtoamatrixelementofsqueezing-displacingoperatorbetweenthemotherwaveletstatevectorandthestatevectortobetransformedinthecontextofquantummechanics.Inthiswaymanyquantumopticalstates'wavelettransformcanbeeasilyderived.

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简介：-Accordingtobasicequationsoffluidmechanics,thispaperpresentsaunifiedvariationalprincipleoffluidmechanics(UVPFM)byusingtheoptimizationmethodofweightedresiduals(OMWR).Theadvantagesareasfollows,theestablishmentofthefunctionalandthevariationalprincipleiseasy,itcanchangevariousproblemsoffluidmechanicsderivedbybasicequationsintoaunifiedoptimizationproblem,andthesolutionistheoptimumoneinsomesense.AccordingtotheOMWRforthesolitarysubdomain,thispaperusesUVPFMontoanysolitarysubdomainandgivesthesolutionofthehydrodynamicsequationwhichissuitableonlyforthatsolitarysubdomain.AccordingtotheOMWRforsolitarypoint,thispaperusesUVPFMtoanysolitarypointandgivesthesolutionofthehydrodynamicsequation(pointsolution)whichissuitableonlyforthatsolitarypoint.Asthesolutionforthesolitarysubdomainorsolitarypointisdevelopedindependently,thecompatibilitywithothersubdomainorotherpoints,do

简介：浸透的软泥土的失败标准通过不同实验在周期的负担下面被学习。很多周期扭力砍，在unconsolidatedundrained状况下面的浸透的软泥土上的周期的triaxial测试被进行。从测试结果分析，在静态、周期的负担下面的浸透的软泥土的失败满足协定标准，这被看见。来自不同测试压力状态的结果不与测试压力状态或限制压力有关。它能处于一般压力状态被使用。然后根据协定标准，在在测试压力状态和一般压力状态之间的失败时刻的相等的关系能被建立。在失败时刻的浸透的软泥土的周期的力学特征因此在这篇论文被澄清。而且，一个理论基础用伪静电干扰被提供elasto塑料的周期的力量模型评估周期的适用的能力。

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简介：Dynamicstrainaging（DSA）isanimportantphenomenoninsolutehardenedmetalsandseri-ouslyaffectsthemechanicalpropertiesofmetals.DSAisgenerallyinducedbytheinteractionbetweenthemovingdislocationsandthemobilesoluteatoms.Inthispaper,onlytheinteractionbetweenmovingdisloca-tionsandmobilesoluteatomsinadislocationcorearea（coreatmosphere）willbetakenintoaccount.Toes-rablishtheconstitutivemodelwhichcandescribetheDSAphenomenon,weimprovedtheZerilli-Armstrongdislocation-mechanics-basedthermalviscoplasticconstitutiverelation,andaddedtheeffectoftheinteractionbetweenthemovingdislocationsandcoreatmosphere.BecausetheconstitutiverelationestabhshedisbasedontheZerilh-Armstrongrelation,itcandescribenotonlytheDSAphenomenon,butalsothemechanicalbe-haviorofmetalsoverabroadrangeoftemperatures（77K～1000K）andstrainrate(10-4～104s-1).Themodelpredictionfortantalumfitswellwiththeexperimentaldata.

简介：BackgroundEnd阶段脚关节关节炎损害联合功能和病人活动性。全部的脚关节代替是一个外科的过程对待严重脚关节关节炎。SaltoTalaris解剖脚关节TM(STAA)被设计模仿正常脚关节解剖和脚关节运动的屈曲/扩展。这研究的目的是与结束阶段在gait.MethodsFive病人期间在脚关节关节功能和力学上检验STAA脚关节代替的效果单方的脚关节关节炎被招募。病人们执行了水平在2个场合上走在一个实验室背景，在以前并且在STAA脚关节手术以后的3个月。美国矫形的脚和脚关节社会(AOFAS)hindfoot分数被获得。A12照相机运动俘获系统被用来执行走的分析。步法temporo空间的参数和脚关节关节力学被评估。配对的学生t测试和非参量的Wilcoxon匹配测试被执行在在外科前和外科以后的走conditions.ResultsCompared之间的biomechanical变量检验差别到pre外科的条件，在3月post-STAA外科，病人们在AOFAShindfoot经历了更大的改进分数(p=0.0001)；STAA脚关节证明31%在脚关节关节旅行(p=0.045)增加，22%在脚关节plantarflexor时刻(p=0.075)增加，60%尽最大努力增加吸收(p=0.023)，并且68%尽最大努力增加生产(p=0.039)。病人们也证明26%在走速度(p=0.005)增加，迈进长度(p=0.013)的20%增加，在两倍支持时间(p=0.043)的15%减少，和在全部的位置的5%减少预定(p=0.055)在手术以后的.ConclusionThree月，STAA病人在脚关节功能和步法参数经历了改进。STAA脚关节在象走那样的每日的活动期间表明了改进脚关节力学。

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简介：Designofenergeticmaterialsisanexcitingareainmechanicsandmaterialsscience.Energeticcompositematerialsareusedaspropellants,explosives,andfuelcellcomponents.Energyreleaseinthesematerialsareaccompaniedbyextremeevents:shockwavestravelattypicalspeedsofseveralthousandmeterspersecondandthepeakpressurescanreachhundredsofgigapascals.Inthispaper,wedevelopareactivedynamicscodeformodelingdetonationwavefeaturesinonesuchmaterial.Thekeycontributioninthispaperisanintegratedalgorithmtoincorporateequationsofstate,Arrheniuskinetics,andmixingrulesforparticledetonationinaTaylor–Galerkinfiniteelementsimulation.Weshowthattheschemecapturesthedistinctfeaturesofdetonationwaves,andthedetonationvelocitycompareswellwithexperimentsreportedinliterature.

简介：Thispaperreviewstherecentprogressinthestudiesofexperimentalrockmechanicsandtectonophysicsconcern-ingseismologyandphysicsoftheEarth'sinteriorinChina.Theprogressispresentedinthefollowingaspects:a)Alotofresultsofexperimentandnumericalsimulationenrichourknowledgeofthebrittlefracturingprocessundertheconditionwithheterogeneityinmaterialandstructure;b)Somenewresultsonfrictionalbehaviorofnon-homogeneousfaultsrevealthecomplexityoffaultingbehavior;c)Somenewresultsonthebrittle-plastictran-sitionandplasticflowareobtained;especiallytheimportantprogressisobtainedontheologicalpropertiesofrocksinthelowercrustandtheuppermantle;d)Alotofexperimentalresultsareobtainedonrockphysicsathightem-peratureandpressureandhavebeenusedinstudyofmaterialcompositionandstate.TheseresultsprovideusefulinformationforunderstandingthephysicalpropertiesanddeformationmechanismsofmaterialoftheEarth'sinte-riorandearthquakephysics.

简介：Basedonthethermodynamictheory,anorthotropicdamageconstitutivemodelwasdevelopedtodescribethenonlinearmechanicalbehaviorofC/SiCcomposites.Thediferentnonlinearkinematicandisotropichardeningfunctionswereadoptedtodescribeaccuratelythedamageevolutionprocesses.Thedamagevariablesweredefinedwiththedamagedmodulusandtheinitialundamagedmodulusonenergyequivalenceprinciple.Theinitialorthotropyanddamagecouplingwerepresentedinthedamageyieldfunction.Tensileandin-planeshearloadingandunloadingtestswereperformed,andagoodagreementbetweenthemodelandtheexperimentalresultswasachieved.

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简介：Ceramicsaregoodalternativetometalasbearingcouplematerialsbecauseoftheirbetterwearresistance.AFiniteElement(FE)studywasperformedtoinvestigatethecontactmechanicsandstressdistributionofCeramic-on-Ceramic(COC)hipresurfacingprostheses.Itwasfocusedinparticularonaparametricstudytoexaminetheeffectsofradialclearance,loading,aluminacoatingontheimplants,bonequality,andfixationofcup-boneinterface.Itwasfoundthatareductionintheradialclearancehadthemostsignificanteffectonthepredictedcontactpressuredistributionamongalloftheparametersconsideredinthisstudy.Itwasdeterminedthattherewasasignificantinfluenceofnon-metallicmaterials,suchastheboneunderneaththebearingcomponents,onthepredictedcontactmechanics.Stressshieldingwithinthebonetissuewasfoundtobeamajorconcernwhenregardingtheuseofceramicasanalternativetometallicresurfacingprostheses.Therefore,usingaluminaimplantswithametalbackingwasfoundtobethebestdesignforceramicresurfacingprosthesesinthisstudy.Theloading,bonequality,andacetabularcupfixationconditionswerefoundtohaveonlyminoreffectsonthepredictedcontactpressuredistributionalongthebearingsurfaces.

简介：Anapproachbasedoncontinuumdamagemechanicstofatiguelifepredictionforstructuresisproposed.Anewfatiguedamageevolutionequationisdeveloped,inwhichtheparametersareobtainedinasimplewaywithreferencetotheexperimentalresultsoffatiguetestsonstandardspecimens.WiththeutilizationofAPDLlanguageontheANSYSplatform,afiniteelementimplementationispresentedtoperformcouplingoperationondamageevolutionofmaterialandstressredistribution.ThefatiguelivesofsomenotchedspecimensandaPitch-change-linkarepredictedbyusingtheaboveapproach.Thecalculatedresultsarevalidatedwithexperimentaldata.

简介：WeconstructaclassofintegrablegeneralizationofTodamechanicswithlong-rangeinteractions.ThesesystemsareassociatedwiththeloopalgebrasL(Cr)andL(Dr)inthesensethattheirLaxmatricescanberealizedintermsofthec=0representationsoftheaffineLiealgebrasCr(1)andDr(1)andtheinteractionspatterninvolvedbearsthetypicalcharactersofthecorrespondingrootsystems.WepresenttheequationsofmotionandtheHamiltonianstructure.Thesegeneralizedsystemscanbeidentifiedunambiguouslybyspecifyingtheunderlyingloopalgebratogetherwithanorderedpairofintegers(n,m).Itturnsoutthatdifferentsystemsassociatedwiththesameunderlyingloopalgebrabutwithdifferentpairsofintegers(n1,m1)and(n2,m2)withn2＜n1andm2＜m1canberelatedbyanestedHamiltonianreductionprocedure.Forallnontrivialgeneralizations,theextracoordinatesbesidesthestandardTodavariablesarePoissonnon-commute,andwheneithernorm≥3,thePoissonstructurefortheextracoordinatevariablesbecomessomeLiealgebra(i.e.theextravariablesappearlinearlyontheright-handsideofthePoissonbrackets).Inthequantumcase,suchgeneralizationswillbecomesystemswithnoncommutativevariableswithoutspoilingtheintegrability.

简介：Afiniteelementisestablishedforanalyzingthedynamicalmechanicsanddeformationofsteelframeathightemperaturewhenitisrapidlycooleddownbyspraywaterinfirefighting.Thesimulationresultshowsthatremarkablemechanicalcouplingeffectsareproducedintheprocess,andthesectionalstressinrapidcoolingdownisfoundconsiderablylargerthanthatinheating-up.Meanwhile,thestressanddeformationofabeammainlyrelatedtocoolingrateandlocationaremuchlargerthanthoseofacolumninrapidcooling.Infirefighting,thestructureonthefirstorsecondfloorwasmoredangerousthanthoseonotherfloorsinrapidcooling.Theseresultscouldprovideatheoreticalreferenceforthedesignofsteelstructureandfirefighting.