简介:-Thedynamicbucklingofelasto-plasticcylindricalshellsunderaxialfluid-solidimpactisinvestigatedtheoretically.Asimplifiedliquid-gas-structuremodelisgiventoapproximatelyimitatetheproblem.Thebasicequationofthestructureisderivedfromaminimumprincipleindynamicsofelasto-plasticcontinuaatfinitedeformation,andtheflowtheoryofplasticityisemployed.Theliquidisincompressibleandthegasiscompressedadiabatically.Anumberofnumericalresultsarepresentedandthecharacteristicsofthebucklingbehaviorunderfluid-solidimpactareillustrated.
简介:Abundantfluid-meltinclusionsarefoundintheaegirine-augite-baritepegmatiteandcarbonatiteveinsintheMianningREEdeposit,Sichuan,Theyweretrappedinearlystagefluoriteandquartzfromasalt-meltsystemattemperatureshigherthan5000℃,Meanwhile,fluidinclusionsarealsopresentinalrgeamountsinbastnaesite.Homogenizedbetween150and270℃,theseinclusionsarethoughttoberepresentativeofthephysico-chemicalconditionsofREEmineralization.TheseresultsshowthattheMianningREEdepositisoftypicalhydrothermalorigindevelopedfromasalt-meltsystem.
简介:VegetativecellsofPorphyrayezoensisareisolatedwithseasnailenzymeandculturedonthesolidifiedagarmedium.Theresultsofexperimentsshowthattheisolatedcellscansurvive,divideandregeneratewellonthemediumsolidifiedwithagar.Thefirstdivisiononthesolidmediumstartsafter7days'culture,4dayslaterthantheliquidculture.Thesurvivalrateofisolatedcellsis71.3%onthesolidmedium,lowerthanthe86.2%ofthatinseawater.Thalli,thalloids,conchocelis,spermatangiaandmulticellularmassesaredevelopedonthesolid/mediuminthefirstmonth,slowlybutnormally.Spermatangiasacsdisappearwithin4weeks.Withoutaddingnutrientliquidontothesurfaceofsolidmediumorinjectingseawaterundertheagarlayerinordertokeepmoisture,thethalliandcellgroupsreleasemonosporestoformnewthalliinsteadofenlargingtheirareasafter5weeks'culturing.Somemonosporesregeneratenewthalli.Othermonosporeslosetheirpigmentsandminimizetheirvolumeanddividequicklytoformlightpinkcalli.After16weeks,numerouscallicanbeseenonthesolidmediumandafter24weeks'culturing,almostonlycalliandconchoceliscanbeseen.Ifthecalliareimmersedinseawater,themonosporesarereleasedandmaydevelopintoyoungthallus.
简介:Thepresentpaperisfocussedontheeffectsofviscousandturbulentshearstressesonbothverticalvelocityandconcentrationdistributionsinlargesuspensionofsands.Whentheflowcarrieslargeamountofsedimentsinsuspension,thepropertiesoffluidmixturearechangedintermsofmodifiedviscosity,densityandfallvelocity,andhencetheflowcharacteristics.Theoreticalmodelshavebeendevelopedforbothvelocityandconcentrationprofiles,takingintoaccounttheviscousandturbulentshearstresses,whicharethefunctionofvolumetricconcentration.Comparisonoftheoreticalmodelswithexperimentaldatarevealsthat(i)themodifiedvelocityandconcentrationprofilesagreewellwiththeobserveddataforhighsuspension,(ii)thehigherthesedimentsuspension,thesmallerthevonKarmanconstant,and(iii)sedimentdiffusioncoefficientislessthanmomentumdiffusioncoefficientforfinesandsinsuspension.
简介:Thispaperreviewsthedynamicsofoceanpipesaspiratingfluidandpresentsaselectivereviewoftheresearchundertakenonit.Itfocusesontheequationsofmotion,fluid-solidinteractionattheinletofthefreeendofthepipe,thestabilitymechanismofpipesaspiratingsteadyfluid,etc.Inparticular,someunresolvedorpartlyresolvedissuesontheseimportantaspectsarediscussed.Finally,thepromisingfuturedevelopmentinthisareaisdiscussed.
简介:现在的学习试图在差错地区揭示postseismic液体压力的恢复时期,提供进地震复发的卓见。数字建模基于2D被执行在地震差错以内模仿液体活动的简单分层的差错阀门模型。为了表明postseismic液体的特征,处于自然状态迫使,构造运动的干扰没被考虑。postseismic液体压力的恢复时期包括一个suddenchanging时期和一个长得多的波动时期。当模特儿的结果证明那差错渗透和孔是敏感参数并且与在地震差错地区的液体压力的恢复时期相对地成正比。当渗透从10把-15归结为10-18m2,时,恢复时期correspondently从400~2000年增加。上面、更低的液体压力被阀门封口分开,引起他们在相反的趋势的变化。
简介:Offshoredrillingandproductionoperationscanresultinspillsorleaksofhydrocarbonsintoseabedsediments,whichcanpotentiallycontaminatethesesedimentswithoil.Ifthisoillatermigratestothewatersurfaceithasthepotentialfornegativeenvironmentalimpacts.Forpropercontingencyplanningandtoavoidlargerconsequencesintheenvironment,itisessentialtounderstandmechanismsandratesforhydrocarbonmigrationfromoilcontainingsedimentstothewatersurfaceaswellashowmuchwillremaintrappedinthesediments.Itisbelievedthattheamountofoiltransportedoutofthesedimentcanbeaffectedbytidalpumping,acommonformofsubterraneangroundwaterdischarge(SGD).However,wecouldfindnostudyexperimentallyinvestigatingthephenomenonoffluidflowinsubseasedimentscontainingoilandtheeffectsoftidalpumping.Thisstudypresentsanexperimentalinvestigationoftidalpumpingtodetermineifitisapossiblemechanismthatmaycontributetotheappearanceofanoilsheenontheoceansurfaceaboveasedimentbedcontainingoil.AnexperimentalapparatuswasconstructedofclearPVCpipeallowingforoilmigrationtobemonitoredasitflowedoutofasandpackcontainingoil,whiletidalpressureoscillationswereappliedinthreedifferentmanners.Theeffectoftidalpumpingwassimulatedviacompressionofairabovethewater(whichsimulatedtheincreasingstaticheadfromtidalexchange).Experimentalresultsshowthatsustainedoilreleaseoccurredfromalltests,andtestswithoscillatingpressureproducedforlongerperiodsoftime.Furthermore,theexperimentalresultsshowedthattheoilmigrationratewasaffectedbygrainsize,oilsaturation,andoscillationwavetype.Inalloscillatingexperimentstherateandultimaterecoverywaslessthanthecomparablestaticexperiments.Fortheconditionsstudied,theexperimentalresultsindicatethatwithanoscillatingpressureontopofasandpack,movementofanon-replenishingsourceofoilissuppressed
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简介:Fluidinclusionsinmineralsfilledinporesofreservoirrockscanbeusedasagoodindicatorofporegenesisanddevelopmentsoastoshedlightonoilgeneration,migrationandaccumulation.TherelationshipbetweenporeevolutionandoilgenerationhasbeenestablishedbasedonfluidinclusionstudiesontheLowerOrdoviciancarbonatereservoirstrataintheOrdosBaisn,NorthwestChina.Sevenstagesofporositydevelopmentcanberecogmized.i.e.,thepenecontemporaneous,theearlyandmiddle-latediagenetic,thesupergene,theearly,middleandlatere-buryingstages.Thedissolutionporesanfissuresformedinthesupergeneandmiddle-latereburyingstageandthestructuralfracturesformedinthelatere-buryingstageconstitutethemajortrapsofoilandgas.ThemajorphaseofoilmigrationandaccumulationtookplacebetweenLateJurassicandCretaceous,Correspondingtothemiddleandlatere-buryingstages.ThegenerationandaccumulationofoilcanbecloselyrelatedtoYenshaniantectonics.
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简介:SeismicPvelocitystructureisdeterminedfortheupper500kmoftheinnercoreandlowermost200kmoftheoutercorefromdifferentialtraveltimesandamplituderatios.ResultsconfirmtheexistenceofagloballyuniformFregionofreducedPvelocitygradientinthelowermostoutercore,consistentwithironenrichmentneartheboundaryofasolidifyinginnercore.Pvelocityoftheinnercorebetweenthelongitudes45oEand180oE(quasi-EasternHemisphere)isgreaterthanorequaltothatofanAK135-Freferencemodelwhereasthatbetween180oWand45oE(quasi-WesternHemisphere)islessthanthatofthereferencemodel.Observationofthisheterogeneitytoadepthof550kmbelowtheinnercoreandtheexistenceoftransitionsratherthansharpboundariesbetweenquasi-hemispheresfavoreithernoorveryslowinnercoresuperrotationoroscillationswithrespecttothemantle.DegreeoneseismicheterogeneitymaybebestexplainedbyactiveinnercorefreezingbeneaththeequatorialIndianOceandominatingstructureinthequasi-EasternHemisphereandinnercoremeltingbeneathequatorialPacificdominatingstructureinthequasi-WesternHemisphere.Variationsinwaveformsalsosuggesttheexistenceofsmaller-scale(1to100km)heterogeneity.
简介:-Accordingtobasicequationsoffluidmechanics,thispaperpresentsaunifiedvariationalprincipleoffluidmechanics(UVPFM)byusingtheoptimizationmethodofweightedresiduals(OMWR).Theadvantagesareasfollows,theestablishmentofthefunctionalandthevariationalprincipleiseasy,itcanchangevariousproblemsoffluidmechanicsderivedbybasicequationsintoaunifiedoptimizationproblem,andthesolutionistheoptimumoneinsomesense.AccordingtotheOMWRforthesolitarysubdomain,thispaperusesUVPFMontoanysolitarysubdomainandgivesthesolutionofthehydrodynamicsequationwhichissuitableonlyforthatsolitarysubdomain.AccordingtotheOMWRforsolitarypoint,thispaperusesUVPFMtoanysolitarypointandgivesthesolutionofthehydrodynamicsequation(pointsolution)whichissuitableonlyforthatsolitarypoint.Asthesolutionforthesolitarysubdomainorsolitarypointisdevelopedindependently,thecompatibilitywithothersubdomainorotherpoints,do
简介:Basedonthermalsimulationexperiment,interactionsbetweenvolcanicfluidsandsourcerockswerestudied.Gasgenerationsinthedrysystemandfluidsystemunderdifferenttemperatureswereanalyzed.Theresultsshowedthatthevarioustypesofsourcerocksaresimilarincomposition,containinggaseousC1-C5hydrocarbons,H2andCO2whosegasyieldsincreasewithincreasingtemperature.ThegasyieldofsourcerocksoftypeisⅠthehighest,followedbytypeⅡ,andthatofsourcerocksoftypeisⅢthelowest,indicatingthattheyieldofhydrocarbongasesisrelatedtotheirhydrocarbongeneratingpotential.AlthoughthegeneratingpotentialoftypeisⅢthelowest,itcanstillberegardedasausefulgassourcewhenitisburieddeeplyenough.Thebasicvolcanicfluidrestrainsthegenerationofgaseoushydrocarbonsindifferenttypesofsourcerocks,butpromotesthegenerationofinorganicgases.