简介：摘要：天然石材广场砖因外观效果极佳被广泛应用于各类建筑工程中，但天然石材成本高，石料本身存在色差和裂纹、质量不稳定；同时由于部分石材多孔的特性，抗渗、抗污能力不足，表面容易染色，不易维护和保养。反打装饰面抗污防裂预制混凝土大型广场砖秉承装配式建筑“绿色、节能、环保”的理念，在工厂进行工业化生产，现场进行装配化施工。预制混凝土广场砖具有造型美观、防滑耐磨、抗渗抗污、轻质高强、绿色环保、综合成本更低的优势，被广泛应用于园林景观步行道、广场前坪、市政道路等项目。

简介：Themainobjectiveofthispaperistostudythesingularnatureofthecrack-tipstressandelectricdisplacementfieldinafunctionallygradientpiezoelectricmediumhavingmaterialcoefficientswithadiscontinuousderivative.Theproblemisconsideredforthesimplestpossibleloadingandgeometry,namely,theanti-planeshearstressandelectricdisplacementin-planeoftwobondedhalfspacesinwhichthecrackisparalleltotheinterface.Itisshownthatthesquare-rootsingularityofthecrack-tipstressfieldandelectricdisplacementfieldisunaffectedbythediscontinuityinthederivativeofthematerialcoefficients.Theprob-lemissolvedforthecaseofafinitecrackandextensiveresultsaregivenforthestressintensityfactors,elec-tricdisplacementintensityfactors,andtheenergyreleaserate.

简介：Theproblemofananti-planeGriffithcrackmovingalongtheinterfaceofdissimilarpiezoelectricmaterialsissolvedbyusingtheintegraltransformtechnique.Itisshownfromtheresultthattheintensityfactorsofanti-planestressandelectricdisplacementaroundthecracktiparedepen-dentonthespeedoftheGriffithcrackaswellasthematerialcoefficients.Whenthetwopiezoelectricmaterialsareidentical,thepresentresultwillbereducedtotheresultfortheproblemofananti-planemovingGriffithcrackinhomogeneouspiezoelectricmaterials.

简介：Thescatteringproblemofanti-planeshearwavesinafunctionallygradedmaterialstripwithanoff-centercrackisinvestigatedbyuseofSchmidtmethod.Thecrackisverticallytotheedgeofthestrip.ByusingtheFouriertransform,theproblemcanbesolvedwiththehelpofapairofdualintegralequationsthattheunknownvariableisthejumpofthedisplacementacrossthecracksurfaces.Tosolvethedualintegralequations,thejumpofthedisplacementacrossthecracksurfaceswasexpandedinaseriesofJacobipolynomials.Numericalexampleswereprovidedtoshowtheeffectsoftheparameterdescribingthefunctionallygradedmaterials,thepositionofthecrackandthefrequencyoftheincidentwavesuponthestressintensityfactorsofthecrack.

简介：AmechanicalmodelisestablishedformodeⅡinterfacialcrackstaticgrowingalonganelastic-elasticpowerlawcreepingbimaterialinterface.Forfrictionalcontactofboundaryconditionsoncrackfaces,asymptoticsolutionsofthestressesandstrainsofneartip-crackaregot.Itwasshownthatinstablecreepgrowingphase,elasticdeformationandviscousdeformationareequallydominantinthenear-tipfield,thestressandstrainhavethesamesingularityandthereisnottheoscillatorysingularitythefield.Throughnumericalcalculation,itisshownthatthefrictionalcoefficientηnotablyinfluencethecrack-tipfield.

简介：ＳｔａｔｉｃｓｏｌｕｔｉｏｎｏｆａｃｒａｃｋｄｅｇｅｎｅｒａｔｅｄｆｒｏｍｄｙｎａｍｉｃｓｏｌｕｔｉｏｎｏｆａｐｒｏｐａｇａｔｉｎｇｃｒａｃｋＳｈｉ－ＹｕＬＩ（李世愚）ａｎｄＹｕｎ－ＴａｉＣＨＥＮ（陈运泰）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ...

简介：Intergranularslowcrackgrowthinzirconiapolycrystalisdescribedwithacohesivezonemodelthatsimulatemechanicallythereaction-rupturemechanismunderlyingstressandenvironmentallyassistedfailure.A2Dpolycrystalisconsideredwithcohesivesurfacesinsertedalongthegrainboundaries.Theanisotropicelasticmodulusandgrain-to-grainmisorientationareaccountedfortogetherwithaninitialstressstaterelatedtotheprocessing.Aminimumloadthresholdisshowntooriginatefromtheonsetofthereaction-rupturemechanismtoproceedwhereaminimumtractionisreachedlocallyandfromthemagnitudeoftheinitialcompressionstresses.Thisworkaimsatprovidingreliablepredictionsinlonglastingapplicationsofceramics.

简介：Formulationintermsofhypersingularintegralequationsfortheinteractionbetweenstraightandcurvedcracksinplaneelasticityisobtainedusingthecomplexvariablefunctionsmethod.Thecurvedlengthcoordinatemethodandasuitablenumericalschemeareusedtosolvesuchintegralsnumericallyfortheunknownfunction,whicharelaterusedtofindthestressintensityfactor,SIF.

简介：Asolutionispresentedforaclassoftwo-dimensionalelectroelasticbranchedcrackproblems.ExplicitGreen’sfunctionforaninterfacecracksubjecttoanedgedislocationisdevelopedusingtheextendedStrohformulationallowingthebranchedcrackproblemtobeexpressedintermsofcoupledsingularintegralequations.Theintegralequationsareobtainedbythemethodthatmodelsakinkasacontinuousdistributionofedgedislocations,andthedislocationdensityfunctionisdefinedonthelineofthebranchcrackonly.Competitionbetweencrackextensionalongtheinterfaceandkinkingintothesubstrateisinvestigatedusingtheintegralequationsandthemaximumenergyreleaseratecriterion.Numericalresultsarepresentedtoshowtheeffectofelectricfieldonthepathofcrackextension.

简介：AnewmechanicsmodelbasedonPeierlsconceptispresentedinthispaper,whichcanclearlycharacterizetheintrinsicfeaturesnearatipofaninterfacialcrack.Thestressanddisplacementfieldsarecalculatedundergeneralcombinedten-sileandshearloadings.Theneartipstressfieldsshowsomeoscillatorybehaviorsbutwithoutanysingularityandthecrackfacesopencompletelywithoutanyoverlappingwhenremotetensileloadingiscomparablewithremoteshearloading.Afracturecriterionforpredictinginterfacetoughnesshasbeenalsoproposed,whichtakesintoaccountfortheshieldingeffectsofemitteddislocations.Thetheoreticaltoughnesscurvegivesexcellentprediction,ascomparedwiththeexistingexperimentdata.

简介：本文从crack技术的初级阶段讲起逐表深入的介绍了一些crack知识或经验。在引出本文之前，我想说的是请大家能正视crack,据我所知的我认识的朋友和了解的cracker,大部分都不是为了金钱而破解的，很多人只是把它当作自己的兴趣而已，所谓的CCG、BCG等破解组织是软件盗版的基地更是无中生有，据我所知每个破解组织的规章其中就严格规定不得和盗版集团发生任何联系。国外也有破解组织而且水平比国内要高，为什么国外的软件能成功？这恐怕不仅仅是crack惹的祸！同时crack同样给我国的共享软件提供了巨大的能量。

简介：

简介：

简介：Notopterygiumincisum(QH)hasbeenusedforthetreatmentofrheumatoidarthritis(RA),andvolatileoilsmaybeitsmainlybioactiveconstituents.ThepresentstudywasdesignedtoanalyzethevolatilecompoundsinQHandtodeterminetheanti-arthriticcapacityofNotopterygiumvolatileoilsandthepotentialmechanismofaction.ThevolatilecompoundsanalysiswasconductedbyGC-MS.Theanti-arthriticcapacitytestofthevolatileoilswasconductedonadjuvant-inducedarthritis(AIA)rats.Theanti-inflammatorypropertywastestedinNOreleasemodelinRAW264.7cells.Endothelialcellswereusedtoevaluatetheanti-proliferativeandanti-tubeformativeeffects.70compoundswereanalyzedbyGC-MSinthevolatileoils.NotopterygiumvolatileoilsweakenedtheratAIAinadose-dependentmanner(2,4,and8gcrudedrug/kg).TheNOproductionbyRAW264.7wasdecreasedbymorethan50%inNotopterygiumvolatileoils(5,15,and45μg·mL-1)pretreatedgroups.NotopterygiumvolatileoilsalsoinhibitedEAhy926cellproliferationandfurtherdelayedEAhy926cellcapillarytubeformationinaconcentration-dependentmanner.Theanti-NOproductive,anti-proliferative,andanti-tubeformativeeffectsofNotopterygiumvolatileoilsstronglysuggestedthatthetherapeuticeffectofQHinAIAmightberelatedtothepotentanti-inflammatoryandanti-angiogeniccapacitiesofthevolatileoils.

简介：这篇论文在有限厚度的一次非同类的材料旅行认为一架反飞机是动人的快克。shear模量和长带的集体密度为平衡方程为有分析答案的功能的形式的一个班被考虑。这个问题借助于单个不可分的方程技术被解决。裂缝尖端附近的压力地被获得。结果被阴谋在裂缝尖端域上显示出材料非同质和快克移动速度的效果。裂缝分叉行为也被讨论。纸指出一个适当破裂标准的使用为在非同类的材料学习一个动人的裂缝的稳定性是必要的。预言不稳定的裂缝生长是否将被提高或延迟，强烈依赖于使用的破裂标准的类型。基于分析，看起来最大值“反飞机砍”在裂缝尖端附近的应力是为在非同类的材料的动人的裂缝的一个合适的失败标准。

简介：Thepresentworkisconcernedwithapenny-shapedDugdalecrackembeddedinaninfinitespaceofone-dimensional(1D)hexagonalquasicrystalsandsubjectedtotwoidenticalaxisymmetrictemperatureloadingsontheupperandlowercracksurfaces.ApplyingDugdalehypothesistothermo-elasticresults,theextentoftheplasticzoneatthecracktipisdetermined.Thenormalstressoutsidetheplasticzoneandcracksurfacedisplacementarederivedintermsofspecialfunctions.Forauniformloadingcase,thecorrespondingresultsarepresentedbysimplifyingtheprecedingresults.Numericalcalculationsarecarriedouttoshowtheinfluenceofsomeparameters.

简介：Carbon-containingrefiactoriesareeasilyoxidizedathightenperature,thusmakingserviceliferapidlydrop.Theanti-oxidationmethods,suchasimpregnationandaddinganti-oxidatonagents,can'tmeettherequire-mentsofindustry'sdevelopmentandsomespecialcases,Byanalyzingthecharcteristicsofseveraloxidesandnon-oxidesrawmaerials,theoxidationresistantmechanismoftherefractoryanti-oxidationcoatings(RAOC),whichpossessthecharacteristcofself-healingathighttemperature,isdiscussed.

简介：

简介：Fordecades,nacrehasinspiredresearchersbecauseofitssophisticatedhierarchicalstructureandremarkablemechanicalproperties,especiallyitsextremefracturetoughnesscomparedwiththatofitspredominantconstituent,CaCO3,intheformofaragonite.Crackdeflectionhasbeenextensivelyreportedandregardedastheprincipaltougheningmechanismfornacre.Inthispaper,ourattentionisfocusedoncrackevolutioninnacreunderaquasi-staticstate.Weusethenotchedthree-pointbendingtestofdehydratednacreinsituinascanningelectronmicroscope(SEM)tomonitortheevolutionofdamagemechanismsaheadofthecracktip.Theobservationsshowthatthecrackdeflectionactuallyoccursbyconstrainedmicrocracking.Onthebasisofourfindings,acrackpropagationmodelisproposed,whichwillcontributetouncoveringtheunderlyingmechanismsofnacre’sfracturetoughnessanditsdamageevolution.Theseinvestigationswouldbeofgreatvaluetothedesignandsynthesisofnovelbiomimeticmaterials.

简介：Abriefaccountisprovidedoncrack-tipsolutionsthathaverecentlybeenpublishedintheliteraturebyemployingtheso-calledGRADELAmodelanditsvariants.TheGRADELAmodelisasimplegradientelasticitytheoryinvolvingoneinternallengthinadditiontothetwoLame'constants,inanefforttoeliminateelasticsingularitiesanddiscontinuitiesandtointerpretelasticsizeeffects.Thenon-singularstrainsandnon-singular(butsometimessingularorevenhypersingular)stressesderivedthiswayunderdifferentboundaryconditionsdifferfromeachotherandtheirphysicalmeaninginnotclear.Thisisdiscussedwhichfocusontheformandphysicalmeaningofnon-singularsolutionsforcrack-tipstressesandstrainsthatarepossibletoobtainwithintheGRADELAmodelanditsextensions.