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495 个结果
  • 简介:Inthispaper,researchofaftershockmechanismsisreviewed,includingheterogeneityofmediumandstress,mechanicalloading,fluidintrusionandstresscorrosion,andratestatedependence.Previousstudieshaveindicatedthattheheterogeneityofmediaandstressisthebasicpremiseofaftershocksgenerated.Fromthepointviewofmechanics,transientcreepandafterslipcanexplainthedecayofaftershocksinashorttimeafteramainshockandtherelaxationofstresstendstointerpretthecharacteristicsoflong-termaftershocks.Fluidintrusionandstresscorrosioncontroltheevolutionprocessoftheaftershocksundercertainconditions.Theinteractionbetweenthefaultsperturbedbythemainshockalwaysexistsduringtheaftershockactivities.Allkindsofmodelsandthetheorieswanttocomplywiththetwobasicpower-lawrelationships---theG-RlawandOmorilawtosomeextent.

  • 标签: 地震机理 综述 余震活动 应力腐蚀 唐山 机械载荷
  • 简介:重要努力在在水泥揭示thaumasite形成的机制被作了,它继续与歧义和纠纷是充满的。化学方法被采用综合纯C3S,C2S,C3A,ettringite,和thaumasite,和X光检查衍射(XRD),拉曼光谱学和红外线的光谱学(红外)被用来从另外的水合物识别thaumasite。调查thaumasite形成的直接线路,C3S,C2S,石膏,和钙碳酸盐被用来准备水泥粘贴以便ettringite形成的干扰能被避免。thaumasite形成的间接线路被考虑C3thaumasite上的A或ettringite内容形成。结果证明那个thaumasite罐头毫无疑问在适当条件下面当忍受铝的矿物质或ettringite不在时被产生,当ettringite存在支持thaumasite形成时。没有证据在这个工作支持异构的成核线路。方法在这提到工作能肯定被用来调查thaumasite形成的机制,这被结束,并且thaumasite能形成由直接并且woodfordite线路。

  • 标签: 碳硫硅钙石 混凝土 机制 形成机理 钙矾石 化学法合成
  • 简介:The"ShanghaiFive"mechanismwasborninApril1996whentheRepublicofKazakhstan,thePeople’sRepublicofChina,theKyrgyzstanRepublic,theRussianFederationandtheRepublicofTajikistanheldasummitmeetinginShanghai.China.Thereaftertheyholdsummiteveryyearandeachofthemplayhostinturn.TheDushanbeSummitofJuly5,2000wastheirfifthmeeting.AfterfivesummitsfiveheadsofstateextensiveIyexchangedViewsofcommonconcern,and

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  • 简介:Organicconductorisakindoforganiccompoundwhichhasspecialelectronicandmagneticproperties.Theresearchoftheorganiccompoundshasreceivedconsiderableattentionbecauseoftheirpotentialapplicationsinmanyareas.Themolecularconductiveunitsaretheoreticallyinvestigatedaswellastheirenergygapandchargedistribution.Therelationshipofconductivityandmicro-mechanismisdiscussed.

  • 标签: ORGANIC conductor ENERGY BAND CONDUCTIVITY
  • 简介:Carbon-containingrefiactoriesareeasilyoxidizedathightenperature,thusmakingserviceliferapidlydrop.Theanti-oxidationmethods,suchasimpregnationandaddinganti-oxidatonagents,can'tmeettherequire-mentsofindustry'sdevelopmentandsomespecialcases,Byanalyzingthecharcteristicsofseveraloxidesandnon-oxidesrawmaerials,theoxidationresistantmechanismoftherefractoryanti-oxidationcoatings(RAOC),whichpossessthecharacteristcofself-healingathighttemperature,isdiscussed.

  • 标签: 耐火材料 抗氧化机理 制备 碳化物 原料 氧化硅
  • 简介:AbstractIn modern society, subarachnoid hemorrhage, mostly caused by intracranial aneurysm rupture, is accompanied by high disability and mortality rate, which has become a major threat to human health. Till now, the etiology of intracranial aneurysm has not been entirely clarified. In recent years, more and more studies focus on the relationship between hemodynamics and intracranial aneurysm. Under the physiological condition, the mechanical force produced by the stable blood flow in the blood vessels keeps balance with the structure of the blood vessels. When the blood vessels are stimulated by the continuous abnormal blood flow, the functional structure of the blood vessels changes, which becomes the pathophysiological basis of the inflammation and atherosclerosis of the blood vessels and further promotes the occurrence and development of the intracranial aneurysm. This review will focus on the relationship between hemodynamics and intracranial aneurysms, will discuss the mechanism of occurrence and development of intracranial aneurysms, and will provide a new perspective for the research and treatment of intracranial aneurysms.

  • 标签: Hemodynamics Inflammation Atherosclerosis Intracranial aneurysm
  • 简介:Heterosisistheuniversalphenomenainnature,anditsformationmechanismhasbeenthefocusofresearch.Onthisbasis,anumberoftheoreticalhypotheseshavebeenproposedforthereasonofheterosis,suchasthedominancehypothesis,epistaticeffect,generegulationnetworks,etc.Forthepastyears,manyresearchershaveattemptedtoelaboratethemechanismofheterosisatphysiological&biochemicallevelandmolecularlevel.Theresultsshowedheterosisplantshaveastrongerphotosyntheticcapacity,relativelywell-developedtissuesandgreateradaptionandbufferingabilitytoexternalenvironment.Theheterosisisoftenmorepronouncedinrelativelylowlight,lowtemperatureandlowCO2concentration.Inaddition,geneticdistance,differencesingeneexpressionandDNAmethylationareallcloselyrelatedwithheterosis.Thisstudyreviewedresearchresultsofforestryandagriculture,anddiscussedthefutureresearchdirectionofthisfield.

  • 标签: PLANT HETEROSIS MECHANISM PHYSIOLOGY BIOCHEMISTRY MOLECULAR
  • 简介:ShortDriveMechanismforFaradayCup¥ZhangGongXiang;JiangFakuiandLouMeilingThenewECRsourcebeamlinewhichisunderconstructionneedsth...

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  • 简介:ThewholechemicaletchingprocessonaP-typepolycrystallinesiliconsubstratewithresistivity1-2Ω·cmisdescribed.Theformationmechanismofporouspolycrystallinesilicon(PPS)microstructurewasinvestigated.ThosehowtheinitialpitswereformedandanuniformmorphologyofPPSwasobtainedareexplained.Twotypesofetchingmechanismwerecharacterizedasdefectcontrolreactionanddiffusioncontrolreaction.ThemorphologyformedaftertheisotropicacidicsolutionetchingwithdifferentetchingtimeandHF/HNO3concentrationwascomparedwiththeeffectofthesameetchingprocessafteranisotropicalkalineetching.Thestudyshowedthatthethicknessofporouspolycrystallinesiliconlayerwithchemicalacidicetchingentirelydependedontheexistenceofvarioustypesofdefects.

  • 标签: PPS 扩散控制 缺陷控制 点缺陷 线缺陷
  • 简介:Thispaperprobesintotherelationshipamongindividualbenefits,benefitsofthecountry,commonbenefitsofallhumansinlanduseandlandresourcesecurity.Thefollowingbalancedlandusemodelisproposed:theharmo-niousandinteractiverelationshipbetweenmanandnature,twomainbodiesoflandecologicalsystem,constitutesthemechanismoflandresourcessecurity.Thefeedbackrelationshipbetweenmanandnatureisthebasisforthelandresourcessecurityandthecoreistherelationshipamongpeopleestablishedforthebenefitequilibriuminlanduse.Theconflictsinlandusestemfromtherarityoflandresourceandthesolutiontothoseconflictsinharmonyhelpslandresourcesecurity.

  • 标签: 人与自然 土地利用 土地资源 土地资源安全
  • 简介:Fromthegroupmovementofthebedloadwithinthebottomlayer,detailsofthenonlineardynamiccharacteristicsofbedloadmovementarediscussedinthispaper.Whetherthesedimentisinitiatedintomotioncorrespondstowhethertheconstanttermintheequationisequaltozero.Ifconstanttermiszeroandnodispersiveforceisconsidered,theequationrepresentsthetraditionalShieldsinitiationcurve,andifconstanttermiszerowithoutthedispersiveforcebeingconsidered,thenanewShieldscurvewhichismuchlowerthanthetraditionaloneisgot.Thefixedpointoftheequationcorrespondstotheequilibriumsedimenttransportofbedload.Inthemutationanalysis,wehavefoundthattheinflectionpointisthedemarcationpointofbreaking.Intheory,thebreakingpointcorrespondstothedividingboundaryline,acrosswhichthebedformchangesfromflatbedtosandrippleorsanddune.ComparedwiththeexperimentaldataofChatouHydraulicLabinFrance,theconclusionsareverified.

  • 标签: 非线性机制 非线性动态特性 输沙 运动负荷 启动曲线 常数项
  • 简介:Introductionα-Aminonitrile(oraminoacetonitrile)isakindofreactivebioorganicmolecules,anditmayexistininsterstellarclouds.itsimportanceliesinthata-aminonitrilemayplayaroleinthegenerationoflargecarbon-nitrogenchainmolecules.Bymeansofflashvacuumthermolysisandgas-solidreaction(FVT-GSR)tech-nique,Guillemin,etal.,studiedthethermolysisofa-aminonitrile,theyconsideredthattheeliminationofHCN(shownasfollowing)isakeystepinmanyreactionsofα-

  • 标签: THERMOLYSIS α-Aminonitrile TRANSITION STATE IRC PATH
  • 简介:FeedbackMechanisminDecisionSupportSytemsTXFedbackMechanisminDecisionSupportSystemsSunZhanshanInstituteofSE.DalianMaritimeUnive...

  • 标签: : FEEDBACK MECHANISM DECISION MAKING DECISION
  • 简介:DeformationdatuminsourcemechanisminversionSHOU-WENGONG(巩守文,QING-LIANGWANG(王庆良),YI-QINGZHU(祝意青)andBINGCHEN(陈兵)(SecondCrustalDe...

  • 标签: DEFORMATION DATUM FOCAL mechanism INVERSION LEVELLING