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16 个结果
  • 简介:我们综合有单个多孔的壳和Ag@Au/Ag@Au的空结构的Ag@Aunanoparticles由使用流电的代替反应加倍壳并且调查他们的线性、非线性的光性质。我们的结果证明空多孔的nanoparticles的表面电浆子回声波长能被控制HAuCl4的体积容易在可见、近的红外线的区域在一个宽范围调节。双shelledAg@Au/Ag@Aunanoparticles的非线性的光折射被电浆子回声显著地提高。我们的调查结果可以在生物传感器和非线性的光nanodevices发现应用。

  • 标签: 金纳米粒子 双壳 光学响应 非线性光学性质 合成 表面等离子体
  • 简介:Intermediate Mass Fragment Emission in Ar+Ag CollisionsIntermediateMassFragmentEmissioninAr+AgCollisions¥WuEnjiu;ZhengJiwen;W...

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  • 简介:TheannealingbehaviorofAgnanoparticlesinsilicawithandwithoutdefectswasinvestigatedinthisstudy.SilicasampleswithandwithoutArionpre-irradiationwereimplantedwithAgionsandthenannealedattemperaturefrom300to850℃.UV-VISspectroscopyandTEMwereusedtocharacterizetheopticalabsorbancepropertyandsizedistributionofAgnanoparticles,respectively.OpticalabsorbanceresultsshowthattheabsorbanceintensityofSPR(SurfacePlasmonResonance,SPR)peakfromAgnanoparticlesinthesamplewithpre-irradiationisstrongerthaninthesamplewithoutpre-irradiation,whichindicatesthatthedefectsproducedbypre-irradiationpromptthenucleationofAgnanoparticles.Duringannealing,theSPRpeakshiftstoshortwavelengthdirection,asshowninFig.1.

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  • 简介:ThispaperinvestigatesthesolidificationbehaviouroftheAg—Cueutecticalloymeltundercooledupto100K.ItisrevealedthatlamellareutecticsgrowinadendriticformintheAg-Cueutecticmeltwithundercoolingequaltoorgreaterthan76K.Asundercoolingincreases,theremeltedfractionoftheprimaryeutecticsduringrecalescencerises.Thesevereremeltingandthesubsequentripeningoftheprimaryeutecticdendritesleadtotheformationofanomalouseutectics.

  • 标签: 共晶体生长 合金熔体 Cu 异常 机制 凝固行为
  • 简介:Inordertodeepentheunderstandingoftherelationshipbetweenfundamentalproperties(including:microstructureandcomposition)andphotocatalyticperformance,fourbismuthatecompounds,including:LiBiO3,NaBiO3,KBiO3,andAgBiO3,areregardedasresearchexamplesinthepresentwork,becausetheyhaveparticularcrystalstructuresandsimilarcompositions.Usingdensityfunctionaltheorycalculations,theirstructural,electronic,andopticalpropertiesareinvestigatedandcomparedsystematically.Firstofall,thecalculatedresultsofcrystalstructuresandopticalpropertiesareinagreementwithavailablepublishedexperimentaldata.Basedonthecalculatedresults,itisfoundthatthetunneledorlayeredmicro-structuralpropertiesleadtothestrongerinteractionbetweenbismuthandoxygen,andtheweakerinteractionbetweenalkaline-earthmetaland[BiO6]octahedron,resultinginthefeatureofmulti-bandgapsinthecasesofLiBiO3,NaBiO3,andKBiO3.ThisconclusionissupportedbythecaseofAgBiO3,inwhichthefeatureofmulti-bandgapsdisappears,duetothestrongerinteractionbetweenthenoblemetaland[BiO6]octahedron.Thesepropertieshavesignificantadvantagesinthephotocatalyticperformance:absorbinglowenergyphotons,rapidlytransferringenergycarriers.Furthermore,thefeaturesofelectronicstructuresofbismuthatecompoundsarewellreflectedbytheabsorptionspectra,whichcouldbeconfirmedbyexperimentalmeasurementsinpractice.Combinedwiththecalculatedresults,itcouldbeconsideredthatthecrystalstructuresandcompositionsofthephotocatalystdeterminetheelectronicstructuresandopticalproperties,andsubsequentlydeterminethecorrespondingphotocatalyticperformance.Thus,anovelBi-basedphotocatalystdrivenbyvisible-lightcouldbedesignedbyutilizingspecificcompositionstoformfavorableelectronicstructuresorspecificmicro-structurestoformabeneficialchannelforenergycarriers.

  • 标签: 电子结构 光催化剂 光催化性能 弱相互作用 计算结果 NA
  • 简介:COandformaldehyde(HCHO)oxidationreactionswereinvestigatedovermesoporousAg/Co3O4catalystspreparedbyone-pot(OP)andimpregnation(IM)methods.Itwasfoundthattheone-potmethodwassuperiortotheimpregnationmethodforsynthesizingAg/Co3O4catalystswithhighactivityforbothreactions.ItwasalsofoundthatthecatalyticbehaviorofmesoporousCo3O4andAg/Co3O4catalystsforthebothreactionswasdifferent.AndtheadditionofsilveronmesoporousCo3O4didnotalwaysenhancethecatalyticactivityoffinalcatalystforCOoxidationatroomtemperature(20C),butcouldsignificantlyimprovethecatalyticactivityoffinalcatalystforHCHOoxidationatlowtemperature(90C).Thehighsurfacearea,uniformporestructureandtheprettygooddispersiondegreeofthesilverparticleshouldberesponsiblefortheexcellentlow-temperatureCOoxidationactivity.However,forHCHOoxidation,theadditionofsilverplayedanimportantroleintheactivityenhancement.AndthesilverparticlesizeandthereducibilityofCo3O4shouldbeindispensableforthehighactivityofHCHOoxidationatlowtemperature.

  • 标签: MESOPOROUS materials Co3O4 AG CO OXIDATION
  • 简介:Measurement of Linear Momentum Transfer in Ar+Bi and Ar+Ag Systems at 25MeV/uMeasurementofLinearMomentumTransferinAr+BiandAr+...

  • 标签: System
  • 简介:IsotopesTemperaturein40Ar+158Tband108AgReactionsat30MeV/u¥DaiGuangxi;FuYanbiao;HeZhiyong;DuanLimin;LiZuyuandZhangBaog?..

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  • 简介:WepresentthetemperaturedependentelectricaltransportmeasurementsofAg/Si(111)-(√3×√3)R30°bytheinsitumicro-four-pointprobemethodintegratedwithscanningtunnelingmicroscopy.Thesurfacestructurecharacterizationsshowhexagonalpatternsatroomtemperature,whichsupportstheinequivalenttriangle(IET)model.Ametal-insulatortransitionoccursat-115K.Thelowtemperaturetransportmeasurementsclearlyrevealthestronglocalizationcharacteristicsoftheinsulatingphase.

  • 标签: surface CONDUCTIVITY METAL-INSULATOR transition LOCALIZATION SCANNING
  • 简介:TernarymetalchalcogenidesemiconductorAg8SnS6,whichisanefficientphotocatalystundervisiblelightradiation,isstudiedbyplane-wavepseudopotentialdensityfunctionaltheory.Aftergeometryoptimization,theelectronicandopticalpropertiesarestudied.Ascissoroperatorvalueof0.81eVisintroducedtoovercometheunderestimationofthecalculationbandgaps.Thecontributionofdifferentbandsisanalyzedbyvirtueoftotalandpartialdensityofstates.Furthermore,inordertounderstandtheopticalpropertiesofAg8SnS6,thedielectricfunction,absorptioncoefficient,andrefractiveindexarealsoperformedintheenergyrangefrom0to11eV.TheabsorptionspectrumindicatesthatAg8SnS6hasagoodabsorbencyinvisiblelightarea.Surfaceenergiesandworkfunctionsof(411),(413),(211),and(112)orientationshavebeencalculated.TheseresultsrevealthereasonforanoutstandingphotocatalyticactivityofAg8SnS6.

  • 标签: 第一原理方法 功函数 表面能 光学性质 电子 密度泛函理论
  • 简介:CrystallineTiO2(P25)andisolatedtitanatespeciesinaZSM-5structure(TS-1)weremodifiedwithAuandAg,respectively,andtestedinthegas-phasephotocatalyticCO2reductionunderhighpurityconditions.Thenoblemetalmodificationwasperformedbyphotodeposition.LightabsorbancepropertiesofthecatalystsareexaminedwithUV–Visspectroscopybeforeandaftertheactivitytest.Inthegas-phasephotocatalyticCO2reduction,itwasobservedthatthecatalystswithAgnanostructuresaremoreactivethanthosewithAunanostructures.Itisthusfoundthattheenergeticdifferencebetweenthebandgapenergyofthesemiconductorandthepositionoftheplasmonisinfluencingthephotocatalyticactivity.Potentially,plasmonexcitationduetovisiblelightabsorptionresultsinplasmonresonanceenergy,whichaffectstheexcitationofthesemiconductorpositively.Therefore,anoverlapbetweenbandgapenergyofthesemiconductorandmetalplasmonisneeded.

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  • 简介:Afacilestep-by-stepapproachisdevelopedforsynthesizingthehigh-efficiencyandmagneticrecyclableFe_3O_4@SiO_2@Ag@Nitrepang-likenanocomposites.ThismethodinvolvescoatingFe_2O_3nanorodswithauniformsilicalayer,reductionin10%H_2/AratmospheretotransformtheFe_2O_3intomagneticFe_3O_4,andfinallydepositingAg@Nicore-shellnanoparticlesontheL-lysinemodifiedsurfaceofFe_3O_4@SiO_2nanorods.Thefabricatednanocompositesarefurthercharacterizedbyx-raydiffraction,transmissionelectronmicroscopy,scanningelectronmicroscope,Fouriertransforminfraredspectroscopy,andinductivelycoupledplasmamassspectroscopy.TheFe_3O_4@SiO_2@Ag@Nitrepang-likenanocompositesexhibitremarkablyhighercatalyticefficiencythanmonometallicFe_3O_4@SiO_2@AgnanocompositestowardthedegradationofRhodamineB(RhB)atroomtemperature,andmaintainsuperiorcatalyticactivityevenaftersixcycles.Inaddition,thesesamplescouldbeeasilyseparatedfromthecatalyticsystembyanexternalmagnetandreused,whichshowsgreatpotentialapplicationsintreatingwastewater.

  • 标签: 纳米复合材料 降解效率 催化剂 可回收 有机染料 海参