简介：CO2photoreductionisanattractiveprocesswhichallowsthestorageofsolarenergyandsynthesisofsolarfuels.Manydifferentphotocatalyticsystemshavebeendeveloped,whilethealternativephoto-reactorsarestillinsufficientlyinvestigated.Inthiswork,photoreductionofCO2withH2OintoCH4wasinvestigatedinamodifiedconcentratingsolarreactor,usingTiO2andPt/TiO2asthecatalysts.TheTiO2andPt/TiO2sampleswereextensivelycharacterizedbydifferenttechniquesincludingpowderX-raydiffraction（XRD）,N2adsorption/desorptionandUV–visabsorption.ThecatalyticperformanceoftheTiO2andPt/TiO2samplesinthegasphasewasevaluatedunderunconcentratedandconcentratedXe-lamplightandnaturesolarlightwithdifferentconcentratingratios.VariousparametersofthereactionsystemandthecatalystswereinvestigatedandoptimizedtomaximizethecatalyticperformanceofCO2reductionsystem.Comparedwiththenormallightirradiation,theTiO2andPt/TiO2samplesshowhigherphotocatalyticactivity（about6–7times）forreducingCO2intoCH4underconcentratedXe-lamplightandnaturesolarlight.Intherangeofexperimentallightintensity,itisfoundthattheconcentrationofthelightmakesitsuitableforthecatalyticreaction,andincreasestheutilizationefficiencyoftheTiO2andPt/TiO2sampleswhiledoesnotdecreasethequantumefficiency.

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简介：在这研究，塑料闪烁器察觉者的不同参数被Geant4模拟工具箱调查。这些参数由PMT以及表面的半径，长度和位置组成了反射打并且完成选择。而且，二器官的塑料材料的反应时间分布被学习。结果显示收集光光子与PMT半径头一起有一种线性关系。另外，PMT的垂直地点与光光子收集有一种非线性的关系。然而，收集由增加PMT长度或动人的PMT头减少了水平位置。二塑料闪烁器材料的反应功能在对试验性的出版结果的好同意。另外，Geant4放射运输代码能模仿事件放射光子并且预言随后的事件到PMT头很好。结果显示BC-404有更快的焕发性质对BC-400器官的闪烁器材料。在Geant4产量之间的比较说明最好的反射镜材料和表面为光光子完成类型，这是地面TiO2。

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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：Two-dimensional（2D）graphitecarbonnitride（g-C3N4）nanosheetshavebeensuccessfullyusedasasaturableabsorber（SA）inapassivelyQ-switchedNd:LLFlaserat1.3μmforthefirsttime,tothebestofourknowledge.Underanincidentpumppowerof9.97W,theshortestpulsedurationof275nswasacquiredwithoutputpowerof0.96Wandpulserepetitionrateof154kHz,resultinginapulseenergyof6.2μJ.Inaddition,thesaturableabsorptionbehaviorsofzero-dimensional12nmg-C3N4nanoparticles（g-C3N4-NPs）andthree-dimensionalorderedmesoporousg-C3N4（mpg-C3N4）werealsoobserved,althoughtheirmorphologyandstructurewerequitedifferentfrom2Dg-C3N4.Theexperimentalresultsintroducethepotentialapplicationofg-C3N4nanomaterialsasSAsinQ-switchedlasers.

简介：One-potachievementofethyllevulinatefromcassavawasconductedinethanol-watersystemoverseveralsimplesulfatesaltcatalysts.Al2（SO4）3catalysthadthebestperformanceinsynthesizingethyllevulinatecomparingwiththoseofaseriesofsulfatesalts.Thehighestyieldsofethyllevulinatewasupto39.27%aswellas7.78%levulinateacidwhencassavawascatalyzedinethanolmediumbyadding10wt%water.13Cand1HNMRspectroscopicinvestigationsconfirmedthatisomerizationofglucosetofructoseoverAl2（SO4）3catalystisanimportantstepinproducingethyllevulinateandlevulinateacid.DuetoaggregationsofAl3+underhydrothermalconditions,tinyamountofAl3+weredetectedinfiltrateatthepercentageof0.32%evenifinabsolutewater.BronstedandLewisacidscouldimprovetheyieldofethyllevulinateandlevulinateacidbysynergisticeffect.AllresultssuggestedthatA12（SO4）3wasasimpleandefficientcatalystforethyllevulinateandlevulinateacidproduction.

简介：Ablackphosphorus（BP）saturableabsorber（SA）solutionwithdifferentconcentrations（1.0and0.5mg/ml）isfabricatedwiththeliquid-phaseexfoliationmethod.ByusingtheBP-SA,acompactdiode-pumpedpassivelyQ-switchedNd：YV04laserisdemonstrated.OnereflectingBragggratingsisusedastheoutputcouplerformodeselection.ByinsertingthoseBP-SAsolutionsinthelasercavity,themaximumsinglelongitudemode,Q-switchedoutputpowersof126mWat692.5kHzand149mWat630.3kHzareachievedatthepumppowerof8.0W,correspondingtothepulsedurationsof144nsand196ns,respectively.Moreover,longitudinal-modecharacteristicsofQ-switchedoutputlaserindifferentopticalcavitylengthsbasedontwo-kindBP-SAsolutionconcentrationsareinvestigated.OurresultsshowthatBP-SAcouldalsobedevelopedasaneffectiveSAfortheQ-switched,singlelongitudinalmodepulselaser.

简介：Nanostructuredmetaloxidesderivedfrommetalorganicframeworkshavebeenshowntobepromisingmaterialsforapplicationinhighenergydensitylithiumionbatteries.Inthiswork,porousnanostructuredZnCo2O4andCo3O4weresynthesizedbyafacileandcost-effectiveapproachviathecalcinationofMOF-74precursorsandtestedasanodematerialsforlithiumionbatteries.ComparedwithCo3O4,theelectrochemicalpropertiesoftheobtainedporousnanostructuredZnCo2O4exhibithigherspecificcapacity,moreexcellentcyclingstabilityandbetterratecapability.Itdemonstratesareversiblecapacityof1243.2mAh/gafter80cyclesat100mA/gandanexcellentrateperformancewithhighaveragedischargespecificcapacitiesof1586.8,994.6,759.6and509.2mAh/gat200,400,600and800mA/g,respectively.ThesatisfactoryelectrochemicalperformancessuggestthatthisporousnanostructuredZnCo2O4ispotentiallypromisingforapplicationasanefficientanodematerialforlithiumionbatteries.

简介：Wereportontheperformanceofacontinuous-waveNd:GdVO4laserin-banddiode-pumpedat912nmwithhighoutputpowerandexcellentbeamquality.Thelaserproducedanoutputpowerof19.8Wat1063nmwithanopticalefficiencyof59.3%andslopeefficiencyof62.7%.Thelaserthresholdwas2.04Woftheabsorbedpumppower,andthelaseroutputbeamqualitywas≤1.2inthehorizontalandverticaldirections.Thestrengthofthermallensingatfulloutputpower（33.4Wofabsorbedpower）wasmeasuredtobeanaverageof8.6diopters.Itisshownthatthermallensingisreducedbyafactorof2withrespecttotheNd:YVO4lasers,thusopeningawayforfurtheroutput-powerscaling.

简介：Bysimultaneouslyemployingbothanelectro-opticmodulatorandcarbonnanotubesaturableabsorber（CNT-SA）inadual-lossmodulator,asubnanosecondsinglemode-lockingpulseunderneathaQ-switchedenvelopewithhighpeakpowerwasgeneratedfromadoublyQ-switchedandmode-locked（QML）Nd:Lu0.15Y0.85VO4laserat1.06μmforthefirsttime,toourknowledge.CNTswithdifferentwallstructures—single-walledCNTs（SWCNTs）,double-walledCNTs（DWCNTs）,andmulti-walledCNTs（MWCNTs）—wereusedasSAsintheexperimenttoinvestigatethesinglemode-lockingpulsecharacteristics.Atpumppowerof10.72W,themaximumpeakpowerof1.312MWwasobtainedwiththeDWCNT.

简介：LiMn2O4andLiNixAlyMn2-x-yO4（x=0.50;y=0.05-0.50）powdershavebeensynthesizedviafacilesolgelmethodusingBehenicacidasactivecheiatingagent.Thesynthesizedsamplesaresubjectedtophysicalcharacterizationssuchasthermogravimetricanalysis（TG/DTA）,X-raydiffraction（XRD）,Fouriertransforminfraredspectroscopy（FT-IR）,field-emissionscanningelectronmicroscopy（FESEM）,transmissionelectronmicroscopy（TEM）andelectrochemicalstudiesviz.,galvanostaticcyclingproperties,electrochemicalimpedancespectroscopy（EIS）anddifferentialcapacitycurves（dQ/dE）.FingerprintXRDpatternsofLiMn2O4andLiNixAlyMn2-x-yO4fortifythehighdegreeofcrystallinitywithbetterphasepurity.FESEMimagesoftheundopedpristinespinelillustrateuniformsphericalgrainssurfacemorphologywithanaverageparticlesizeof0.5μmwhileNidopedparticlesdepictthesphericalgrainsgrowth（50nm）withice-cubesurfacemorphology.TEMimagesofthespinelLiMn2O4showstheuniformsphericalmorphologywithparticlesizeof（100nm）whilelowlevelofAl-dopingspinel（LiNio.5Alo.05Mn1.45O4）displayingcloudyparticleswithagglomeratedparticlesof（50nm）.TheLiMn2O4samplescalcinedat850℃deliverthedischargecapacityof130mAh/ginthefirstcyclecorrespondsto94%coiumbicefficiencywithcapacityfadeof1.5mAh/g/cycleovertheinvestigated10cycles.Amongallfourdopantcompositionsinvestigated,LiNi0.5Al0.05Mn1.45O4deliversthemaximumdischargecapacityof126mAh/gduringthefirstcycleandshowsthestablecyclingperformancewithlowcapacityfadeof1mAh/g/cycle（capacityretentionof92%）overtheinvestigated10cycles.ElectrochemicalimpedancestudiesofspinelLiMn2O4andLiNi0.5Al0.05Mn1.45O4depictthehighandlowrealpolarizationof1562and1100Ω.

简介：我们在Mn50Ni40SnSbx(x=1，2，3，和4)合金。所有准备样品在房间温度与空间组一起展出B2类型结构。Sb的替换增加原子价电子集中并且减少联合起来的房间体积。作为结果，当x增加，magnetostructural转变向更高的温度很快变。在在不同磁场变化下面的磁性的熵的变化在这转变附近被探索。等温的磁化曲线展出典型metamagnetic行为，显示magnetostructural转变能被一个磁场导致。悦耳的martensitic转变和磁性的熵变化建议那Mn50Ni40SnSbx合金是应用在的吸引人的候选人固态制冷。