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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:TheplasmaimpuritycontentsdependsstronglyontransportprocessofdiversiformimpuritywhichproductbythedistributionofimpuritiessourceandtheimpuritiesofSOLandthecoreplasmainthetokamak.Theexperimentalresultssuggestthattheconfinementimprovementisrelatedtotheincreasingrotationvelocityandtothedecreasingedgefluctuation.

  • 标签: HL-2A 边缘等离子体 参数测量 杂质输运 朗缪尔探针
  • 简介:Hydrogen,thecleanestandmostpromisingenergyvector,canbeproducedbysolarintochemicalenergyconversion,eitherbythephotocatalyticdirectsplittingofwaterintoH2andO2,or,moreefficiently,inthepresenceofsacrificialreagents,e.g.,intheso-calledphotoreformingoforganics.Efficientphotocatalyticmaterialsshouldnotonlybeabletoexploitsolarradiationtoproduceelectron–holepairs,butalsoensureenoughchargeseparationtoallowelectrontransferreactions,leadingtosolarenergydriventhermodynamicallyup-hillprocesses.RecentachievementsofourresearchgroupinthedevelopmentandtestingofinnovativeTiO2-basedphotocatalyticmaterialsarepresentedhere,togetherwithanoverviewonthemechanisticaspectsofwaterphotosplittingandphotoreformingoforganics.Photocatalyticmaterialswereeither(i)obtainedbysurfacemodificationofcommercialphotocatalysts,orproduced(ii)inpowderformbydifferenttechniques,includingtraditionalsolgelsynthesis,aimingatengineeringtheirelectronicstructure,andflamespraypyrolysisstartingfromorganicsolutionsoftheprecursors,or(iii)inintegratedform,toproducephotoelectrodeswithindevices,byradiofrequencymagnetronsputteringorbyelectrochemicalgrowthofnanotubearchitectures,orphotocatalyticmembranes,bysupersonicclusterbeamdeposition.

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  • 简介:Anecessaryandsufficientconditionofregularityof(0,1,…,m-2,m)interpo-lationonthezerosoftheLaguerrepolynomialsLn(α)(x)(α≥-1)inamanageableformisestablished.Meanwhile,theexplicitrepresentationofthefundamentalpolynomials,whentheyexist,isgiven.Moreover,itisshownthat,iftheproblemof(0,1,…,m-2,TO)interpolationhasaninfinityofsolutions,thenthegeneralformofthesolutionsisf0(x)+Cf1(x)withanarbitraryconstantC.

  • 标签: LAGUERRE INTERPOLATION regularity uniquely INFINITY explicit
  • 简介:Usingtheextensionhomogeneousbalancemethod,wehaveobtainedsomenewspecialtypesofsolitonsolutionsofthe(2+1)-dimensionalKdVequation.Startingfromthehomogeneousbalancemethod,onecanobtainanonlineartransformationtosimple(2+1)-dimensionalKdVequationintoalinearpartialdifferentialequationandtwobilinearpartialdifferentialequations.Usually,onecanobtainonlyakindofsoliton-likesolutions.Inthisletter,wefindfurthersomespecialtypesofthemultisolitonsolutionsfromthelinearandbilinearpartialdifferentialequations.``

  • 标签: multisoliton (2+1)-dimensions KdV EQUATION
  • 简介:HomogeneousNi2+-dopedtitaniagelwassynthesizedbyasol-gelprocess,andthexerogelwasthenobtainedthroughaginganddrying,leadingtotheformationofNi/TiO2nanocompositeafterheattreatmentunderasuitablereducingatmosphere.TheresultingnanocompositewascharacterizedbyTGA-DSC,TEM,XRDandBETmethods.Theresultsshowthatthestructureandgrainsizeofthenanocompositescouldbemanipulatedbyalteringtheheat-treatmentconditions,andthatthenanocompositepossessesamesoporousstructurewithaporeradiusofca.28nmandaspecifictheanatase-rutilephasetransformation.

  • 标签: 纳米混合物 二氧化钛 二氧化镍 热处理 微观结构
  • 简介:CO2-copolymerbasedpolyurethanefoamsweresynthesizedandcharacterizedinthispaper.Thefoamswerefoundtohavehigherstrengthandlowerheatofcombustionthantheconventionalpolyetherpolyurethanefoams.Theymayfindwideapplicationsinmanyfields.

  • 标签: 合成 CO2 环氧化物 共聚物 聚氨酯泡沫 聚碳酸酯
  • 简介:hePhotocatalyticcharacterizationofTiO2supportedonactivecarbonwasinvestigatedforphotocatalyticdecompositionofdichloroaceticacid.ItwasfoundthatTiO2/ACexhibitedahigherphotocatalyticactivitythanpureTiO2.ThereasonisthatactivecarbonactingaspowerfuladsorbentsupportsmakeshighconcentrationenvironmentsoforganicpollutantmoleculesaroundTiO2particles.

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  • 简介:作者主要学习追踪算法到稳定的Euler系统和等温的Euler系统的波浪前面产生的弱答案的差别。在起始的数据足够地具有的假设下面小全部的变化,稳定的Euler系统和等温的超声的流动的系统的解决方案之间的差别能被起始的不安的全部的变化的立方体围住,这被证明。

  • 标签: 稳定系统 欧拉 等温 2维 逼近 跟踪算法
  • 简介:S.M.LozinskiiprovedtheexactconvergencerateatthezeroofLagrangeinterpolationpolynomialsto|x|basedonequidistantnodesin[-1,1].In2000,M.RevergeneralizedS.M.Lozinskii'sresultto|x|α(0≤α≤1).Inthispaperwewillpresenttheexactrateofconvergenceatthepointzerofortheinterpolantsof|x|α(1<α<2)..

  • 标签: 拉格朗日插值 等节点 收敛性 多项式
  • 简介:CO2capturewithionicliquids(ILs)hasattractedmanyattentions,andmostworksfocusedonabsorptionabilityatambienttemperatures,whileseldomresearchwasconcernedatelevatedtemperatures.ThisnotonlylimitstheCO2absorptionapplicationatelevatedtemperature,butalsothedeterminationoftheoperationconditionoftheCO2desorptiongenerallyoccurringathighertemperature.ThisworkmainlyreportedCO2solubilitiesinILsatelevatedtemperaturesandrelatedpropertieswerealsoprovided.1-alkyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide([CnMIm][Tf2N])ILswereselectedasphysicalabsorbentsforCO2captureinthisworkduetotheirrelativehigherCO2absorptioncapacitiesandgoodthermalstabilities.Thelong-termstabilitytestsshowedthat[CnMIm][Tf2N]isthermallystableat393.15Kforlongtime.CO2solubilitiesin[CnMIm][Tf2N]weresystematicallydeterminedattemperaturesfrom353.15Kto393.15K.ItdemonstratedthatCO2solubilityobviouslyincreaseswiththeincreaseofpressurewhileslightlydecreaseswithincreaseoftemperature.Asthelengthofalkylchainonthecationincreases,CO2solubilityinILsincreases.Additionally,thethermodynamicpropertiesincludingtheGibbsfreeenergy,enthalpy,andentropyofCO2werealsocalculated.

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