简介:SHELLADAPTIVETRIANGULATIONOFTRIMMEDNURBSSURFACEWangHuichengZhangXinfangZhouJiAbstractThepaperpresentsanewapproachfortriangula...
简介:ThenucleiaroundmagicnumberN=126areinvestigatedinthedeformedrelativisticmeanfield(RMF)modelwitheffectiveinteractionsTMA.WefocusinvestigationsontheN=126isotonicchain.TheN=126shellevolutionisstudiedbyanalyzingthevariationsoftwo-neutron(proton)separationenergies,quadrupledeformations,singleparticlelevelsetc.Thegoodagreementoftwo-neutronseparationenergiesbetweenexperimentaldataandcalculatedvaluesisreached.TheRMFtheorypredictsthatthesizesofN=126shellbecomesmallerandsmallerwiththeincreasingofprotonnumberZ.However,theN=126shellexistsinourcalculatedregionallalong.Accordingtothecalculatedtwo-protonseparationenergies,theRMFtheorysuggests~(220)Puisatwo-protondrip-linenucleusintheN=126isotonicchain.
简介:Wesystematicallyanalyzetheexperimentaldataofalphadecayineven-evenheavynucleifarfromstabilityandfindthattheGeiger-Nuttalllawbrea~sforanisotopicchainwhenitsneutronnumberisacrossamarcnumberorthereisadeformedsubshell.Thisbreakcanbeusedtoidentifynewmagicnumbersofsuperheavynuclei.Itisalsodiscoveredthatthereisanewlinearrelationbetweenthelogarithmofhalf-lifeandthereciprocalofthesquarerootofdecayenergyforN=126andN=152isotones.Itcouldbeanewlawofalphadecayfornucleiwithmagicneutronnumbersbutthephysicsbehinditistobeexplored.Thesignificanceoftheseresearchesforthesearchofnewelementsisdiscussed.
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简介:自从以前的世纪的中间,原子原子核的壳模型在集中的使用。很复杂的原子核的这个简单模型,提供对它的许多特征的量的描述。另外的特征从极端图画从小偏差列在后面。我们的朋友和使贡献精液到这的同事AkitoArima回答在原子核的磁性的时刻与Horie以他的著名论文开始[学监。Theor。Phys。11,509(1954)]。在下列,对一个简单例子的详细描述被考虑。它是在在407/2壳>Ca和48Ca并且在在48Ca和56Ni。结果表明壳模型的力量和优雅。他们显示出简洁怎么从复杂性产生。从简单的壳模型的小偏差怎么导致效果,在原子价,中子行动,也被显示出好像他们带电的充电。
简介:WiththeincorporationoftotalLagrangiansmoothedparticlehydrodynamics(SPH)methodequationandmovingleastsquare(MLS)function,thetraditionalSPHmethodisimprovedregardingthestabilityandconsistency.BasedonMindlin-Ressinerplatetheory,theSPHmethodsimulatingdynamicbehaviorviaonelayerofparticlesisappliedtoplate'smid-plane,i.e.,aSPHshellmodelisconstructed.Finally,throughcomparativeanalysesonthedynamicresponseofsquare,stiffenedshellsandcylindricalshellsundervariousstrongimpactloadswithcommonfiniteelementsoftware,thefeasibility,validityandnumericalaccuracyoftheSPHshellmethodareverified.Consequently,furtherresearchesonSPHshellmaywellpavethewaytowardssolvingproblemsinvolvingdynamicplasticdamage,tearingorevencrushing.
简介:Core-shellstructurednanosphereswithmesoporoussilicashellandNicore(denotedasNi@meso-SiO2)arepreparedthroughathree-stepprocess.MonodispersedNiprecursorsarefirstprepared,andthencoatedwithmesoporousSiO2.FinalNi@meso-SiO2spheresareobtainedaftercalcination.TheproductsarecharacterizedbyX-raypowderdiffraction,transmissionelectronmicroscopyandN2adsorption-desorptionmethods.Thesesphereshaveahighsurfaceareaandarewelldispersedinwater,showingahighcatalyticactivitywithaTOFvalueof18.5,andoutstandingstabilityinhydrolyticdehydrogenationofammoniaboraneatroomtemperature.
简介:Thispaperaimstoachieveanalysisandexperimentresultsthatrelatetomechanicscapabilityandstructuralparameterofaspecialsaddleshellofrevolution.Theoreticallyspeaking,thesaddleshellofrevolutionconsistsofatoroidalshellandasphericalshell.Theshellssimultaneousequationscanbesolvedwithharmoniousterms.Where,thefundamentalequationscanbesolvedbyasymptoticexponentialperturbationmethod.TheequationsofspecialsolutioncanbesolvedbyHovozhilovsspecialsolution.Thisnewideaisfromastudyofsomeexistingsolutionsofthetoroidalshell.Theresultshavebeenprovedbycomparedwithsomeexperimentalresults.Theexperimentsaimstostudytheeffectcausedbychangeofmaterialparameter,orbychangeofdifferentgeometricdimensionsofthesaddleshell,whichincludethechangeofthickness,thechangeofradiusofshell,andthechangeofribs.Finally,theacceptedproductofthesaddleshellwerereinforcedbyatoroidalribhasbeensubmitted.
简介:Thispapergivesanexactanalysisofarotatingpiezoelectricsphericalshellwitharbitrarythickness.Atfirst,threedisplacementfunctionsareintroducedtosimplifythebasicequationsofasphericallyisotropic,piezoelectricmedium.Byexpandingthedisplacementfunctionsaswellastheelectricpotentialintermsofsphericalharmonics,thebasicequationsofequilibriumareconvertedtoanuncoupledEulertype,secondorderordinarydifferentialequationandacoupledsystemofthreesecondorderordinarydifferentialequations.Ageneralsolutiontothehomogeneousequationsofequilibriumisthenderived.Thestaticanalysisofarotatingsphericalshellisthenperformedandnumericalexampleispresented.
简介:Experimentalstudyoninitiationofbivalveshellmotiononahorizontalsandbed,underaunidirectionalflowofwater,ispresented.Experimentswerecarriedoutinaflumewiththreetypesofbivalveshells,namelyCoquinaClam,Cross-barredChioneandPonderousArk,totesttheconditionforinitiationofmotion.Theshapeparametersofbivalveshellsaredefinedappropriately.Experimentswereconductedinaflumewithahorizontalbed,andthecriticalshearstresseswereestimatedusingVanoni'sside-wallcorrection.Thecharacteristicparametersaffectingtheinitiationofshellmotiononahorizontalbedinrough-turbulentregimeidentifiedbasedonthephysicalreasoninganddimensionalanalysisaretheShieldsparameter(nondimensionalcriticalshearstress),nondimensionalcompetentmeanvelocity,nondimensionalsandroughness,nondimensionalflowdepthandshapeparameter.EquationsofShieldsparameterandnondimensionalcompetentmeanvelocityfortheinitialmovementofshellsonahorizontalsandbedwithconvexupwardanddownwardconditionsareobtainedusingexperimentaldata.
简介:Sincecannondrumofagileshell-feedingsystemrotatesfrequentlyandintermittently,itsmotionmustbesteady.Outlineofdrivingcamdeterminesthemotionofcannondrum,soitisnecessarytoselecttheproperoutlineofcam.Throughanalysisofparabolicoutlineandcycloidoutlineofthecams,theoutlinethatcombinesthetwocurvesisobtained.Accordingtothedemandofproduction,thevalueoftheoutlineisrevised,andthenthemethodoffittingcurveisusedtogettheexpressionoftheangleofcamandthedisplacementofthedrivenpart.Throughanalyzingthemotionofthecannondrum,itissuggestedthattheangleofthecamisproportiontothedisplacementofthedrivenpart.Thecamwiththespeciallyderivedoutlinecanmovesteadily.