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  • 简介:Basedonthesecond-ordermoments,thispaperderivesananalyticalexpressionoftheM2factoroffour-petalGaussianbeam.TheresultsshowthattheM2factorisonlydeterminedbythebeamordern.Thecorrespondingnumericalcalculationsarealsogiven.Asthebeamorderincreases,theaugmentofM2factorisdisciplinary.AstheexpressionofM2factorisexpressedinseriesformandbecomesmorecomplicated,anewconciseformulaofM2factorisalsopresentedbyusingcurvefittingofnumericalcalculations.When3≤n≤200,themaximumerrorrateoffittingformulawillnotexceed2.6%andtheaverageerrorrateis0.28%.Thisresearchishelpfultotheapplicationsoffour-petalGaussianbeam.

  • 标签: 高斯光束 光波传播 M^2因子 激光技术
  • 简介:MoleculardynamicssimulationsareperformedtostudythegrowthmechanismofCH4-CO2mixedhydrateinxCO2=75%,xCO2=50%,andxCO2=25%systemsatT=250K,255Kand260K,respectively.OursimulationresultsshowthatthegrowthrateofCH4-CO2mixedhydrateincreasesastheCO2concentrationintheinitialsolutionphaseincreasesandthetemperaturedecreases.Viahydrateformation,thecompositionofCO2inhydratephaseishigherthanthatininitialsolutionphaseandtheencagingcapacityofCO2inhydratesincreaseswiththedecreaseintemperature.ByanalysisofthecageoccupancyratioofCH4moleculesandCO2moleculesinlargecagestosmallcages,wefindthatCO2moleculesarepreferablyencagedintothelargecagesofthehydratecrystalascomparedwithCH4molecules.Interestingly,CH4moleculesandCO2moleculesfrequentlyreplacewitheachotherinsomeparticularcagesitesadjacenttohydrate/solutioninterfaceduringthecrystalgrowthprocess.Thesetwospeciesofguestmoleculeseventuallyacttostabilizethenewlyformedhydrates,withCO2moleculesoccupyinglargecagesandCH4moleculesoccupyingsmallcagesinhydrate.

  • 标签: 分子动力学模拟 水合物 CO2 CH4 混合 二氧化碳浓度
  • 简介:Receptor-ligandinteractionsinbloodflowarecrucialtoinitiatesuchbiologicalprocessesasinflammatorycascade,plateletthrombosis,aswellastumormetastasis.Tomediatecelladhesion,theinteractingreceptorsandligandsmustbeanchoredontotwoapposingsurfacesoftwocellsoracellandasubstratum,i.e.,two-dimensional(2D)binding,whichisdifferentfromthebindingofasolubleligandinfluidphasetoareceptor,i.e.,three-dimensional(3D)binding.Whilenumerousworkshavebeenfocusedon3Dkineticsofreceptor-ligandinteractionsintheimmunesystem,2Dkineticsanditsregulationshavebeenlessunderstood,sincenotheoreticalframeworkorexperimentalassayswereestablisheduntil1993.Notonlydoesthemolecularstructuredominate2Dbindingkinetics,buttheshearforceinbloodflowalsoregulatescelladhesionmediatedbyinteractingreceptorsandligands.Here,weprovideanoverviewofcurrentprogressin2Dbindingandregulations,mainlyfromourgroup.Relevantissuesoftheoreticalframeworks,experimentalmeasurements,kineticratesandbindingaffinities,andforceregulationsarediscussed.

  • 标签: 细胞粘附 相互作用 受体 配体 结合动力学 生物学过程
  • 简介:AtomicallythinMoS2filmshaveattractedsignificantattentionduetoexcellentelectricalandopticalproperties.Thedevelopmentofdeviceapplicationsdemandstheproductionoflarge-areathinfilmwhichisstillanobstacle.Inthisworkwedevelopedafacilemethodtodirectlygrowlarge-areaMoS2thinfilmonSiO2substrateviaambientpressurechemicalvapordepositionmethod.Thecharacterizationsbyspectroscopyandelectronmicroscopyrevealthattheas-grownMoS2filmismainlybilayerandtrilayerwithhighquality.Back-gatefield-effecttransistorbasedonsuchMoS2thinfilmshowscarriermobilityupto3.4cm2V-1s-1andon/offratioof105.Thelarge-areaatomicallythinMoS2preparedinthisworkhasthepotentialforwideoptoelectronicandphotonicdeviceapplications.

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  • 简介:SYNTHESISANDANTI-HUMANIMMUNODEFICIENCYVIRUS-1(HIV-1)ACTIVITYOF9-(-PHOSPHONYLMETHOXYETHYL)ADENINE(1)ANDITSREGIOISOMER3-(-PHO...

  • 标签: HIV-1
  • 简介:Asynergyofcomputersimulations,analyticalformulations,andexperimentsprovesveryeffectiveinresearchanddevelopment.Usingnanorodgrowthasanexample,thisletterpresentsthesynergyofthethreecomplementaryapproachesinresearch,anddemonstratesitseffectiveness.Throughthissynergy,atheoreticalframeworkofnanorodgrowthemerges;throughthedirectionofthetheories,experimentalrealizationofsmallestwell-separatednanorodsbecomesreality;throughtherealizationofsuchnanorods,metallicglueinambientenvironmentsbecomestechnicalrealityandcommercialpossibility.

  • 标签: 协同作用 纳米棒 创新 协同效应 实验实现 计算机模拟
  • 简介:Theregularsolutionsofgeneralizedaxisymmetricpotentialequationarecalledgeneralizedaxisymmetricpotentials.Inthispaper,thecharacterizationsoflowerorderandlowertypeofentireGASPintermsoftheirapproximationerror{En}havebeenobtained.

  • 标签: 动力 刃口 气黑
  • 简介:ThisarticleinvestigatestheconvergenceandgrowthofmultipleDirichletseries.TheValironformulaofDirichletseriesisextendedton-tupleDirichletseriesandanequivalencerelationbetweentheorderofn-tupleDirichletseriesanditscoefficientsandexponentsisobtained.

  • 标签: DIRICHLET级数 收敛性 Valiron公式 等价关系 级数和 系数和