简介：Inselectingrationaltypesofundergroundstructuresresistingexplosion,inordertoimprovestressstatesofthestructuralsectionandmakefulluseofmaterialstrengthofeachpartofthesection,theresearchmethodofcompositestructuresispresented.Adoptingtheanalysismethodofmicro-sectionfreebody,equilibriumequations,constraintequationsanddeformationcoordinationequationsaregiven.MakinguseoftheconceptofgeneralizedworkanddirectlyintroducingLagrangemultiplierspecificinphysicalmeaning,thevalidityoftheconstructedgeneralizedfunctionalisprovedbyusingvariationmethod.Therationalrigiditymatchingrelationshipofcompositestructuresectionispresentedthroughexamplecalculations.

简介：WestudyamodifiedversionoftheLane-Emdenequationofthesecondkindmodellingathermalexplosioninaninfinitecylinderandasphere.Wefirstshowthatthesolutiontotherelevantboundaryvalueproblemisboundedandthatthesolutionsaremonotonedecreasing.Theupperbound,thevalueofthesolutionatzero,canbeapproximatedanalyticallyintermsofthephysicalparameters.Weobtainsolutionstotheboundaryvalueproblem,usingboththeTaylorseries(whichworkwellforweaknonlinearity)andthe(5-expansionmethod(validforstrongnonlinearity).Fromhere,weareabletodeducethequalitativebehaviorofthesolutionprofileswithachangeinanyoneofthephysicalparameters.

简介：在最后20年里，因为他们的低biodegradability，从塑料生产的废物正在成为一个环境问题，变得明显。尽管几个方法为再循环浪费塑料被建议了，材料恢复不是现在的问题的一个长期的答案，这通常被接受，并且那个精力或化学恢复是一种更吸引人的选择，包括裂开进单体成分，生产精力的燃烧，并且生产有用中间的化学药品的热或催化的变换。这篇论文是在为精力恢复的最后选择的区域的贡献。有很多份出版物，为裂开聚合物进烃的一个范围报导分子的筛和非结晶的硅石氧化铝催化剂的使用。这里报导的研究工作表明我的能力在击碎聚乙烯进汽油的酣睡的催化剂变化产品。它为我被发现那酣睡的MCM-41催化剂，它有它的crystallinity的裂开的活动增加，与更小的毛孔直径显示更高的活动。烃产品分发强烈显示击碎机制的一个carbenium离子。产品分发也与从热裂开的测试获得的那些相比。

简介：Intheunderwater-shockenvironment,cavitationoccursnearthestructuralsurface.Thedynamicresponseoffluid-structureinteractionsisinfluencedseriouslybythecavitationeffects.Itisalsothedifficultyinthefieldofunderwaterexplosion.Withthetraditionalboundaryelementmethodandthefiniteelementmethod(FEM),itisdifficulttosolvethenonlinearproblemwithcavitationeffectssubjectedtotheunderwaterexplosion.Tosolvethisproblem,undertheconsiderationofthecavitationeffectsandfluidcompressibility,withfluidvisciditybeingneglected,a3Dnumericalmodeloftransientnonlinearfluid-structureinteractionsubjectedtotheunderwaterexplosionisbuilt.Thefluidspectralelementmethod(SEM)andtheFEMareadoptedtosolvethismodel.AftercomparisonwiththeFEM,itisshownthattheSEMismoreprecisethantheFEM,andtheSEMresultsareingoodcoincidencewithbenchmarkresultsandexperimentresults.Basedonthis,combinedwithABAQUS,thetransientfluid-structureinteractionmechanismofthe3Dsubmergedsphericalshellandshipstiffenedplatessubjectedtotheunderwaterexplosionisdiscussed,andthecavitationregionanditsinfluenceonthestructuraldynamicresponsesarepresented.Thepaperaimsatprovidingreferencesforrelevantresearchontransientfluid-structureinteractionofshipstructuressubjectedtotheunderwaterexplosion.