简介：采用对称性破损态方法结合密度泛函理论,选用反铁磁双核配合物[Cu2（MMBPT）2Cl4（H2O）2.5]（MMBPT=3-甲基-4-对甲基苯基-5-（2-吡啶）-1,2,4-三唑）作为研究对象,通过与实验数据相比较,探讨了不同密度泛函方法与基组对计算铜配合物交换耦合常数的准确度.结果表明,4种混合密度泛函DFT（B3LYP,B3P86,B3PW91和PBE0）的计算结果都能和实验所观察到的值-31cm-1符号一致,但只有B3PW91方法得到的结果和实验结果吻合程度最好,同时采用方法B3PW91方法计算所得的交换耦合常数Jab对基组的依赖性较大.研究表明,2个Cu（Ⅱ）离子之间弱的反铁磁相互作用主要源于单占据分子轨道SOMOs小的能量劈裂.

简介：TheinteractionprocessofionsandplasmasisanimportanttopicinIon-Beam-DrivenHighEnergyDensityPhysicsandInertialConfinementFusionresearch.Duetothestrongnon-lineareffectsandthespecialimportanceinICFresearch,moreandmoreemphasishasbeengiventotheinvestigationsforionbeaminlowenergyrangeand/orforplasmawithhighintensity[1;2].Here,weaddressthenewlymeasuredresultsoftheenergylossbyslowionspenetratingthefullyionizedhydrogenplasmatarget.

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简介：Inthispaper,adetailedLiesymmetryanalysisofthe(2+1)-dimensionalcouplednonlinearextensionofthereaction-diffusionequationispresented.Thegeneralfinitetransformationgroupisderivedviaasimpledirectmethod,whichisequivalenttoLiepointsymmetrygroupactually.Similarityreductionandsomeexactsolutionsoftheoriginalequationareobtainedbasedontheoptimalsystemofone-dimensionalsubalgebras.Inaddition,conservationlawsareconstructedbyemployingthenewconservationtheorem.

简介：运用变分方法和临界点理论研究2n阶差分方程边值问题非平凡解的存在性，推广和完善了近期的一些结果．

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简介：CuFe2O4network,preparedviatheelectrostaticspraydepositiontechnique,withhighreversiblecapacityandlongcyclelifetimeforlithiumionbatteryanodematerialhasbeenreported.Thereversiblecapacitycanbefurtherenhancedbycoatinghighelectronicconductivepolypyrrole（PPy）.Atthecurrentdensityof100mA·g-1.Li/CuFe2O4electrodedeliversareversiblecapacityof842.9mAh·g-1whilethereversiblecapacityofLi/PPy-coatedCuFe2O4electrodeincreasesupto1106.7mAh-g’.Ahighcapacityof640.7mAhg"1fortheLi/PPy-coatedCuFe2O4electrodeismaintainedincontrastof398.9mAh·g-1forCuFe2O4electrodeafter60cycles,whichdemonstratesgoodelectrochemicalperformanceofthecompositeduetotheincreaseofelectronicconductivity.Theelectrochemicalimpedancespectroscopy（EIS）furtherrevealsthattheLi/PPy-coatedCuFe2O4electrodehasalowerchargetransferresistancethantheLi/CuFe2C>4electrode.

简介：FortheMonge-Amp`ereequationdetD2u=1,theauthorsfindnewauxiliarycurvaturefunctionswhichattaintheirrespectivemaximaontheboundary.Moreover,theupperboundedestimatesfortheGausscurvatureandthemeancurvatureofthelevelsetsforthesolutiontothisequationareobtained.

简介：采用密度泛函B3LYP/6-311G（d,p）方法对CH3F与C2H3的反应体系进行了理论研究,获得了反应的势能面信息及可能的微观机理.在QCISD（T）/6-311＋＋G（d,p）水平上精确计算了各反应物种的单点能.结果表明,除抽提氢反应外,标题反应还存在抽提氟（R1）、消氟化氢（R2）、消氢（R3）和自由基形成（R4）四类反应.在QCISD（T）/6-311＋＋G（d,p）//B3LYP/6-311G（d,p）水平上,R1,R2,R3和R4反应的能垒分别是163.9,152.2,209.8和224.2kJ·mol-1,相应反应能为-56.6,-164.3,-2.7和-156.0kJ·mol-1,所有反应均放热,为热力学允许的反应.

简介：<正>"角与相交线、平行线"是图形认识中最基础的知识,它们之间又有着紧密的联系.如:1.借助角来研究平面内两条直线之间位置关系,反之角的计算,角与角之间关系的探索与研究,大都以"相交线、平行线"知识作为依据和基础.2.以三角形为载体把平行线的性质和角的知识融合在一起,解决三角形全等问题.它们也是研究"全等三角形、相似三角形、四边形、圆"等其它知识的工具和基础,将有关的计算问题、推理论证问题,转化为这几类知识点来解决.

简介：Two-dimensional(2D)materialshaveattractedgreatresearchinterestsduetotheiruniqueproperties.2DMoS2,unlikeitsbulkformwhichwidelyusedassolidlubricantandcatalyst,isofbrilliantapplicationprospectinnanoelectronicsandoptoelectrnics.Theelectronicdevicesworkinkindsofradiationenvironment.Toevaluatetheionradiationeffectsonmaterialpropertiesandstabilityofdevice,theswiftheavyionradiationeffectonsingle-layerMoS2wasstudiedinthiswork[1??2].

简介：Inthecurrentpaper,dry(CO2)-reformingofglycerol,anewreformingroute,wascarriedoutoveralumina(Al2O3)-supported,non-promotedandlanthanum-promotednickel(Ni)catalysts.Bothsetsofcatalystsweresynthesizedviaawetco-impregnationprocedure.Physicochemicalcharacterizationofthecatalystsshowedthatthepromotedcatalystpossessedsmallermetalcrystallitesize,hencehighermetaldispersioncomparedtothevirginNi/Al2O3catalyst.ThiswasalsocorroboratedbythesurfaceimagescapturedbytheFESEManalysis.Fromtemperature-programmedcalcinationanalysis,thederivativeweightprofilesrevealedtwopeaks,whichrepresentawatereliminationpeakatatemperaturerangeof373to473Kfollowedbynickelnitratedecompositionfrom473to573K.Inaddition,BETsurfaceareameasurementsgave85.0m2g-1forthenon-promotedNicatalyst,whilstthepromotedcatalystsshowedanaverageof1%to6%improvementdependingontheLaloadings.Significantly,reactionstudiesat873KshowedthatglyceroldryreformingsuccessfullyproducedH2.The2%La-Ni/Al2O3catalyst,whichpossessedthelargestBETsurfacearea,gaveanoptimumH2generation(9.70%)ataglycerolconversionof24.5%.

简介：AnovelSr2CuInO3Soxysulfidep-typesemiconductorphotocatalysthasbeenpreparedbysolidstatereactionmethodanditexhibitsintriguingvisiblelightabsorptionpropertieswithabandgapof2.3eV.Thep-typesemiconductorcharacterofthesynthesizedSr2CuInO3SwasconfirmedbyHallefficientmeasurementandMott-Schottkyplotanalysis.First-principlesdensityfunctionaltheorycalculations(DFT)andelectrochemicalmeasurementswereperformedtoelucidatetheelectronicstructureandtheenergybandlocations.Itwasfoundthattheas-synthesizedSr2CuInO3Sphotocatalysthasappreciateconductionandvalencebandpositionsforhydrogenandoxygenevolution,respectively.Photocatalytichydrogenproductionexperimentsunderavisiblelightirradiation(λ>420nm)werecarriedoutbyloadingdifferentmetalandmetal-likecocatalystsonSr2CuInO3SandRhwasfoundtobethebestoneamongthetestedones.

简介：TiO2-loadedactivatedcarbonfibers（ACF）werepreparedbyahydrothermalmethod.Thesampleswerecharacterizedbyscanningelectronmicroscopy（SEM）,X-raydiffraction（XRD）,Fouriertransforminfrared（FT1R）spectrometryandUV-visdiffusereflectancespectra（DRS）.SEMimagesshowedthattheTiO2nanoparticlesweredepositedonthesurfaceofACF,andtheparticlesizeandloadingamountofTiO2werevariedbychangingtheinitialconcentrationoftetrabutyltitanate（TBOT）.TheresultsofanashexperimentshowedthattheloadingamountsofTiO2were18.4%,43.3%,52.5%,75.1%,and91.1%forinitialconcentrationsofTBOTof0.07,014,0.21,0.28,and0.35mol/L,respectively.PhysicalinteractionsplayedanimportantroleintheformationofTiO2/ACFcompositefibersthatabsorbUVandvisiblelight.ComparedwiththoseofACF,improvedadsorptionandphotocatalyticactivitytowardRhodamineB（RhB）wereobservedforTiO2/ACFcompositefiber.TheRhodamineBcouldberemovedefficientlybyTiO2/ACFcompositefibers,andtheTiO2loadingamounthadasignificanteffectonthephotocatalyticactivityofTiO2/ACFcompositefibers.

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简介：Carbonnanotube（CNTs）/Fe-Ni/TiO2nanocompositephotocatalystshavebeensynthesizedbyaninsitufluidizedbedchemicalvapordeposition（FBCVD）method.ThecompositephotocatalystswerecharacterizedbyXRD,Ramanspectroscopy,BET,FESEM,TEM,UV-visspectroscopy,andXPS.TheresultsshowedthattheCNTsweregrowninsituonthesurfaceofTiO2.Fe（lll）inTiO2showednochemicalchangesinthegrowthofCNTs.Ni（Ⅱ）waspartlyreducedtometalNiintheFBCVDprocess,andthemetalNiactedasacatalystforthegrowthofCNTs.ThephotocatalyticactivitiesofCNTs/Fe-Ni/TiO2decreasedwiththeriseoftheFBCVDreactiontemperature.ForthesamplesynthesizedatlowFBCVDtemperature（500℃）,morethan90%andnearly50%ofmethylenebluewereremovedunderUVirradiationin180minandundervisiblelightirradiationin300min,respectively.TheprobablemechanismofsynergisticenhancementofphotocatalysisontheCNTs/Fe-Ni/TiO2nanocompositeisproposed.

简介：CaF2:Ho3+/Yb3+nano-particleswithintensegreenup-conversion(UC)luminescencearesuccessfullysynthesizedviaafacilehydrothermalapproachbyusingNH4FasthefluoridesourceandNa2EDTAasachelatingreagent.PowderXraydiffraction(XRD),transmissionelectronmicroscopy(TEM),fieldemissionscanningelectronmicroscopy(FE-SEM),andUCemissionspectraareusedtocharacterizethestructures,shapes,andluminescentpropertiesofthesamples.TheeffectsfromfluoridesourcesandchelatingreagentsontheformationsofCaF2nano-particlesareinvestigated,andtheformationprocessisalsodeduced.Undertheexcitationofa980-nmlaserdiode,thesampleseachshowagreenup-conversionemissioncenteredat540nmcorrespondingtothe5S2/5F4→5I8transitionsofHo3+.Moreover,theUCmechanismsofHo3+/Yb3+co-dopedCaF2nano-particlesarealsodiscussed.

简介：利用室温液相还原、晶种生长的方法,成功的制备了大小形貌均一、性能稳定且具有磁性的Fe3O4@Cu2O复合纳米粒子,并且对制备的Fe3O4@Cu2O纳米粒子进行了光催化性能的研究.在以紫外光为光源的照射下,合成的Fe3O4@Cu2O纳米粒子对有机染料甲基蓝溶液起到很好的降解作用.更重要的是,在外加磁场的作用下,Fe3O4@Cu2O纳米粒子容易回收,具有良好的可循环利用性能.

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简介：Inthepresentwork,aninterconnectedsandwichcarbon/Si-SiO2/carbonnanospherescompositewaspreparedbytemplatemethodandcarbonthermalvapordeposition（TVD）.ThecarbonconductivelayercannotonlyefficientlyimprovetheelectronicconductivityofSi-basedanode,butalsoplayakeyroleinalleviatingthenegativeeffectfromhugevolumeexpansionoverdischarge/chargeofSi-basedanode.Theresultingmaterialdeliveredareversiblecapacityof1094mAh/g,andexhibitedexcellentcyclingstability.Itkeptareversiblecapacityof1050mAh/gover200cycleswithacapacityretentionof96%.