简介:Inthispaper,weprovethatforholonomicnonconservativedynamicalsystemthePoincareandPoincaré-Cartanintegralinvariantsdonotexist.Insteadofthem,weintroducetheintegralvariantsofPoincaréCartan’stypeandofPoincaré’stypeforholonomienoneonservativedynamicalsystems,andusethesevariantstosolvetheproblemofnonlinearvibration.Wealsoprovethattheintegralinvariantsintro-ducedinreferences[1]and[2]aremerelythebasicintegralvariantsgivenbythispaper.
简介:Accordingtothebasicideaofdual-complementarity,inasimpleandunifiedwayproposedbytheauthor,somebasicprinciplesindynamictheoryofelasticmaterialswithvoidscanbeestablishedsys-tematically.Inthispaper,animportantintegralrelationintermsofconvolutionsisgiven,whichcanbecon-sideredasthegeneralizedprincipleofvirtualworkinmechanics.Basedonthisrelation,itispossiblenoton-lytoobtaintheprincipleofvirtualworkandthereciprocaltheoremindynamictheoryofelasticmaterialswithvoids,butalsotoderivesystematicallythecomplementaryfunctionalsfortheeight-field,six-field,four-fieldandtwo-fieldsimplifiedGurtin-typevariationalprinciples.Furthermore,withthisapproach,thein-trinsicrelationshipamongvariousprinciplescanbeexplainedclearly.
简介:Theexistingfundamentallawsofthermodynamicsformicropolarcontinuumfieldtheoriesarerestudiedandtheirincompletenessispointedout.Newfirstandsecondfundamentallawsforthermostaticsandthermodynamicsformicropolarcontinuaarepostulated.Fromthemallequilibriumequationsandtheentropyinequalityofthermostaticsaswellasallbalanceequationsandtheentropyrateinequalitiesarenaturallyandsimultaneouslydeduced.Thecomparisonsbetweenthenewresultspresentedhereandthecorrespondingresultsdemonstratedinexistingmonographsandtextbooksconcerningmicropolarcontinuummechanicsaremadeatanytime.Itshouldbeemphasizedtonotethat,theproblemofwhythelocalbalanceequationofenergyandthelocalentropyinequalitycouldnotbeobtainedfromtheexistingfundamentallawsofthermodynamicsformicropolarcontinua,isbelievedtobeclarified.
简介:这研究被奉献给磁性的过滤和方法的不同特征的解释这些特征影响重要过滤参数。在毛孔和磁性的粒子和包装的床的磁化性质上的这些地的力量效果的磁场铁磁性的范围创作了,金属薄片被评估。累积的侧面和粒子的俘获区域,在这些区域和粒子俘获半径的分析表情的液体速度的变化被介绍。磁性的过滤器性能上的过滤政体参数的效果被调查。一个分析表达式在过滤速度,过滤器元素的几何学,粒子尺寸和过滤的另外的参数上为对数的效率系数的依赖被获得了。磁性的过滤过程的静止、非静止的方程被给。磁性的过滤器性能的一个表达式被显示出,无尺寸的参数从过滤系统获得了。这些关系为在设计实践的计算是有用的,包括过滤器操作的磁性的过滤器,在建设的建议的预备,和优化和控制的设计。
简介:Thepurposeistoestablishtherathercompleteequationsofmotion,boundaryconditionsandequationofenergyrateofincrementalratetypeformicropolarcontinua.Tothisendtherathercompletedefinitionsforratesofdeformationgradientanditsinversearemade.Thenewrelationsbetweenvariousstressandcouplestressratetensorsarederived.Finally,thecoupledequationsofmotion,boundaryconditionsandequationofenergyrateofincrementalratetypeforcontinuummechanicsareobtainedasaspecialcase.
简介:Thepurposeistoreestablishthecoupledconservationlaws,thelocalconservationequationsandthejumpconditionsofmassandinertiaforpolarcontinuumtheories.Inthisconnectionthenewmaterialderivativesofthedeformationgradient,thelineelement,thesurfaceelementandthevolumeelementwerederivedandthegeneralizedReynoldstransporttheoremwaspresented.Combiningtheseconservationlawsofmassandinertiawiththebalancelawsofmomentum,angularmomentumandenergyderivedinourpreviouspapersofthisseries,arathercompletesystemofcoupledbasiclawsandprinciplesforpolarcontinuumtheoriesisconstitutedonthewhole.Fromthissystemthecouplednonlocalbalanceequationsofmass,inertia,momentum,angularmomentumandenergymaybeobtainedbytheusuallocalization.
简介:ThroughacomparisonbetweentheexpressionsofmasterbalancelawsandtheconservationlawsderivedbyNoether'stheorem,aunifiedmasterbalancelawandsixphysicallypossiblebalanceequationsformicropolarcontinuummechanicsarenaturallydeduced.Amongthem,byextendingthewell-knownconventionalconceptofenergymomentumtensor,therathergeneralconservationlawsandbalanceequationsnamedafterenergy-momentum,energy-angularmomentumandenergy-energyareobtained.Itisclearthattheformsofthephysicalfieldquantitiesinthemasterbalancelawforthelastthreecasescouldnotbeassumeddirectlybyperceivingthroughtheintuition.Finally,someexistingresultsarereducedimmediatelyasspecialcases.
简介:TheSchmidtmethodisadoptedtoinvestigatethefractureproblemofmultipleparallelsymmetricandpermeablefinitelengthmode-IIIcracksinafunctionallygradedpiezoelectric/piezomagneticmaterialplane.Thisproblemisformulatedintodualintegralequations,inwhichtheunknownvariablesarethedisplacementjumpsacrossthecracksurfaces.Inordertoobtainthedualintegralequations,thedisplacementjumpsacrossthecracksurfacesaredirectlyexpandedasaseriesofJacobipolynomials.Theresultsshowthatthestress,theelectricdisplacement,andthemagneticfluxintensityfactorsofcracksdependonthecracklength,thefunctionallygradedparameter,andthedistanceamongthemultipleparallelcracks.Thecrackshieldingefectisalsoobviouslypresentedinafunctionallygradedpiezoelectric/piezomagneticmaterialplanewithmultipleparallelsymmetricmode-IIIcracks.
简介:Basicmagnesiumcarbonatemicrosphereswitharedbloodcell(RBC)-likeappearanceanddiametersof3μmweresynthesizedbyamphiphilicmolecule-participatedself-assemblyunderhydrothermalconditions.Intheself-assembly,sodiumdodecylbenzenesulfonateservedasatemplatefortheformationofMg(OH)2sphericalmicellesandalsoasareactantprecursorthatreleasesCO2toreactwithMg(OH)2.Thegrowthofthemicrospheresisdrivenbythecontinuousgenerationofnewhydrophobiccentersbecauseoftheconsumptionofhydrophilicpoles(—SO3-).Thesurfactant-directedself-assemblycanbeappliedtothesynthesisofothercarbonateormetallicoxideself-assemblies,indicatingthatitisauniversalself-assemblymethodforamphiphilicmolecules.