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  • 简介:ThecharacteristicsofradiationanddryingpropertiesofTiO2bulbinthefixedbedwithinfraredradiationhavebeenstudiedinthispaper,andtheexperimentsondryingdynamicshasbeenanalysedalso.Theoptimizationofheatandmasstransferdatahasbeendetermined,whichcouldprovidethescientificbasisengineeringdesign.

  • 标签: 热传导 TiO2 烘干 红外辐照
  • 简介:Theremediationofgroundwaterwhichcontainschlorinatedorganiccompounds(COCs)bynanoscalebimetalliccatalystshasreceivedincreasinginterestinrecentyears.Thisreportpresentsthedechlorinationof2,4-dichlorophenol(2,4-DCP)byPd-Febimetallicnanoparticlesinthepresenceofhumicacid(HA)toinvestigatethefeasibilityofusingPd-Fefortheinsituremediationofcontaminatedgroundwater.OurexperimentalresultsindicatedthatHAhadanadverseeffectonthedechlorinationof2,4-DCPbyPd-Fenanoparticles.Therateconstantkvaluesof2,4-DCPdechlorinationwere0.017,0.013,0.009,0.006and0.004min?1forHAconcentrationsof0,5,10,15and20mg/L,respectively.TherelationshipbetweenHAdosageandkvaluescanbedescribedasalinearmodel.

  • 标签: 水体污染 2 4-二氢氯化 脱氯作用 金属 乳酸
  • 简介:WedemonstrateafacilerouteforthemassiveproductionofSnCb/carbonnanocompositeusedashigh-capacityanodematerialsofnextgenerationlithium-ionbatteries.ThenanocompositehadauniquestructureofultrafineSnO2nanocrystals(5nm,80wt%)homogeneouslydispersedinamorphouscarbonmatrix.ThisstructuredesigncanwellaccommodatethevolumechangeofLi+insertion/desertioninSnO2,andpreventtheaggregationofthenanosizedactivematerialsduringcycling,leadingtosuperiorcycleperformancewithstablereversiblecapacityof400mAh/gatahighcurrentrateof3.3A/g.

  • 标签: 纳米二氧化锡 锂离子电池 循环过程 非晶碳 阳极材料 分散
  • 简介:Two-dimensional(2D)periodicalAuandindiumtinoxide(ITO)nanocompositearrayshavebeenfabricatedbasedonaself-assemblednanospherelithographytechnique.Abutton-shapedAunanoparticlewasformedoneachhollowhemisphere-shapedITOshell.Importantly,theunderlyingformationmechanismduringthethermaltreatmenthasbeenthoroughlyexploredbycomparingstructuresresultingfromdifferentdepositionconditionsindetail.ComparedtotheAunanoparticlearrayswithoutITOshells,theAu/ITOnanocompositearraysshowedastrongerlocalizedsurfaceplasmonresonanceeffectandhigherabsorptioninthenear-infrared(NIR)region,benefitingfromthefree-electroninteractionenhancementbetweenAuandITO.Thenonlinearopticalpropertieswereinvestigatedusingamodifiedfemtosecondintensity-scansystem,andtheresultsdemonstratedAu/ITOnanocompositearrayswitharemarkabletwo-photonabsorptionsaturationeffectforfemtosecondpulsesat1030nm.TheversatileNIRopticalresponsesindicatethegreatpotentialoftheelaboratelyprepared2DperiodicalAu/ITOnanocompositearraysinmanyapplicationssuchassolarcells,photocatalysis,andnovelnanooptoelectronicdevices.

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  • 简介:ThegatedielectricthicknessdecreasesdramaticallywiththecontinuousscalingofMOSdevices,whichhasseriousconsequencesontheleakagecurrentandthepowerconsumptionoftheSiO2-basedMOSdevices.Hafniumdioxide(HfO2),asakindofhigh-kmaterial,arerecognizedasalternativestoSiO2forfutureadvancedgatedevicesandspaceapplications[1].Radiation-inducedeffectsonconventionalSiO2dielectricshavebeeninvestigated.Now,anenormousamountofeffortwasrequiredtoadaptthenewhigh-ksystemsforradiationhardapplication.

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  • 简介:PlanarringresonatorwaveguidesarefabricatedinthinfilmsofAs2S3chalcogenideglass,depositedonsilicaon-siliconsubstrates.WaveguidecoresaredirectlywrittenbyscanningthefocusedilluminationofafemtosecondTi:sapphirelaseratacentralwavelengthof810nm,throughatwo-photonphoto-darkeningprocess.Alargephotoinducedindexchangeof0.3–0.4refractiveindexunitsisobtained.Theradiusoftheringresonatoris1.9mm,correspondingtoatransmissionfreespectralrangeof9.1GHz.Ahighloaded(intrinsic)Qvalueof110,000(180,000)isachieved.Thethermaldependenceoftheresonatortransferfunctionischaracterized.Theresultsprovidethefirstreport,tothebestofourknowledge,ofdirectlywrittenhigh-Qringresonatorsinchalcogenideglassfilms,anddemonstratethepotentialofthissimpletechniquetowardsthefabricationofplanarlightguidecircuitsinthesematerials.

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  • 简介:最近,大努力在任意的弄歪的设备的制造被作了满足便携、小的电子产品的要求。当它是一个很挑战性的工作时,灵活底层上的高水晶的优秀电影的直接生长是最理想的方法与当前的半导体设备由于简单、兼容的准备技术的优点制作灵活设备,并且通常非结晶、多晶或不连续的单个水晶的电影被完成。这里,我们表明高质量的双性人2Te3单身者由修改的热墙取向附生技术的灵活polyimide底层上的水晶的电影。试验性的结果表明邻近的雏晶协调地被联合形成一部连续电影,尽管迷惑的雏晶的数量由于快生长率被产生。由把一个石英过滤器插入到生长试管,迷惑的雏晶的数字密度有效地由于改进螺线相互作用被减少。而且,灵活双性人2Te3光电导体被制作并且在弯曲的不同的度下面展出强壮的在红外线附近的光导的反应,它也证实对电子应用合适的获得的灵活电影。

  • 标签: 高质量 bi2tea单晶薄膜 柔性衬底 弯曲 探测器
  • 简介:Aseriesofamine-basedadsorbentsweresynthesizedusingsiliceousMCM-41individuallyimpregnatedwithfourdifferentamines(ethylenediamine(EDA),diethylenetriamine(DETA),tetraethylenepentamine(TEPA)andpentaethylenehexamine(PEHA))tostudytheeffectofaminechainlengthandloadingweightontheirCO2adsorptionperformancesindetail.TheadsorbentswerecharacterizedbyFT-IR,elementalanalysis,andthermo-gravimetricanalysistoconfirmtheirstructureproperties.Thermo-gravimetricanalysiswasalsousedtoevaluatetheCO2adsorptionperformanceofadsorbents.Longerchainamine-basedmaterialscanachievehigheramineloadingsandshowbetterthermalstability.TheCO2adsorptioncapacitiesatdifferenttemperaturesindicatethattheCO2adsorptionisthermodynamicallycontrolledoverEDAMCM41andDETA-MCM41,whiletheadsorptionoverTEPA-MCM41andPEHA-MCM41isunderkineticcontrolatlowtemperature.ThechainlengthofaminesaffectstheCO2adsorptionperformanceandtheadsorptionmechanismsignificantly.TheresultsalsoindicatethatCO2adsorptioncapacitycanbeenhanceddespiteofhighoperationtemperatures,ifappropriateamines(TEPAandPEHA)areapplied.However,adsorbentswithshortchainamineexhibithigheradsorptionanddesorptionratesduetothecollaborativeeffectofrapidreactionmechanismsofprimaryaminesandlessdiffusionresistanceofshorterchainlengthamines.

  • 标签: MCM-41 吸附性能 二氧化碳 胺基 材料 硅质
  • 简介:Fourkeyreactions,12C(,)13O,13C(,n)16O,25Mg(p,)26Aland19F(p,)16O,willbestudiedforthefirsttimewithinorneartheastrophysicalrelevantenergyregions(Gamowwindow)atJinpingUndergroundlaboratoryforNuclearAstrophysics(JUNA)[1],whichwilltaketheadvantageoftheultra-lowbackgroundofChinaJinPingundergroundLaboratory(CJPL),highcurrentacceleratorbasedonECRsourceandahighlysensitivedetectionsystem.

  • 标签: Institute MODERN PHYSICS
  • 简介:TheroleoftemperatureontheoxidationdynamicsofCu2OonZnO(0001)wasinvestigatedduringtheoxidationofCu(111)/ZnO(0001)byusingoxygenplasmaastheoxidant.AtransitionfromsinglecrystallineCu2O(111)orientationtomicro-zonephaseseparationwithmultipleorientationswasrevealedwhentheoxidationtemperatureincreasedabove300°C.TheexperimentalresultsclearlyshowtheeffectoftheoxidationtemperaturewiththeassistanceofoxygenplasmaonchangingthemorphologyofCu(111)filmandenhancingthelateralnucleationandmigrationabilitiesofcuprousoxides.Averticaltop-downoxidationmodeandalateralmigrationmodelwereproposedtoexplainthedifferentnucleationandgrowthdynamicsofthetemperature-dependentoxidationprocessintheoxidationofCu(111)/ZnO(0001).

  • 标签: CU2O OXIDATION plasma molecular BEAM EPITAXY
  • 简介:TheeffectsofTiO2onsinteringandnonlinearelectricalpropertiesof(98.5-x)ZnO–0.5MnO2–0.5Co2O3-0.5Bi2O3–xTiO2(x=0.3,0.5,0.7,0.9mol%)ceramicvaristorspreparedbytheceramictechniqueareinvestigatedinthiswork.Theoptimumsinteringtemperatureofthepreparedsamplesisdeducedbydeterminingthefiringshrinkageandwaterabsorptionpercentages.Theoptimumsinteringtemperatureisfoundtobe1200℃,atwhicheachofthesamplesshowsamaximumfiringshrinkageandminimumwaterabsorption.Alsominimumwaterabsorptionappearsinasampleofx=0.9mol%.HighersinteringtemperatureandlongersinteringtimegiverisetoareductioninbulkdensityduetotheincreasedamountofporositybetweenthelargegrainsofZnOresultingfromtherapidgraingrowthinducedbytheliquidphasesintering.ThecrystalsizeofZnOdecreaseswithincreasingTiO2doping.TheadditionofTiO2improvesthenonlinearcoefficientandattainsitsmaximumvalueatx=0.7mol%ofTiO2,furtheradditionnegativelyaffectsit.Adecreaseincapacitanceconsequentlyinthedielectricconstantisrecordedwithincreasingthefrequencyinarangeof30kHz–200kHz.ThetemperatureandcompositiondependencesofthedielectricconstantandACconductivityarealsostudied.Theincreaseoftemperatureraisesthedielectricconstantbecauseitincreasesionicresponsetothefieldatanyparticularfrequency.

  • 标签: ZNO压敏电阻 非线性系数 烧结温度 TIO2 介电性能 掺杂
  • 简介:采用TEA-CO2差分吸收激光雷达进行探测,是建立在气体组分对某些波长激光选择性吸收的基础上的,物质对波长的选择性吸收主要是由原子、分子内部能级的固有特性所决定的,进行探测时的技术难点在于种子源连续波导激光器频率稳定性的实现,也即是外差信号的高稳频技术,因为激光的频率稳定度将影响相干探测的混频效率,并在混频时产生相位噪声,降低系统的信噪比,直接影响探测灵敏度,因此激光雷达在信号发出到返回的时间内的频率稳定度是至关重要的。

  • 标签: 差分吸收激光雷达 光探测 选择性吸收 频率稳定度 实验 稳频技术
  • 简介:WereportontheoperationofpassivelyQ-switchedwaveguidelasersat1μmwavelengthbasedonagraphene∕WS2heterostructureasasaturableabsorber(SA).ThegainmediumisacrystallineNd:YVO4claddingwaveguideproducedbyfemtosecondlaserwriting.Thenanosecondwaveguidelaseroperationat1064nmhasbeenrealizedwiththemaximumaverageoutputpowerof275mWandslopeefficiencyof37%.IncomparisonwiththesystemsbasedonsingleWS2orgrapheneSA,thelasingQ-switchedbyagraphene∕WS2heterostructureSApossessesadvantagesofahigherpulseenergyandenhancedslopeefficiency,indicatingthepromisingapplicationsofvanderWaalsheterostructuresforultrafastphotonicdevices.

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  • 简介:PhotoelectrochemicalandelectrochemicalreductionofCO2intoorganicchemicalsispromisingfordirectlyorindirectlytransformingsolarenergyintochemicalenergyforfurtherutilization.However,researchontheelectroactivespeciesintheseprocesseshasbeenratherlimited.Inthiswork,weinvestigatedpossibleelectroactivespecies(CO2orHCO3–)involvedintheelectrochemicalreductionofKHCO3atelevatedtemperatureswithoutCO2bubbling.TheresultsshowedthatCO,CH4,andC2H4wereproducedafterelectrochemicalreductionof3.0mol/LKHCO3atelevatedtemperatureonaCuelectrodeevenwithoutCO2bubbling,althoughtheirfaradaicefficiencieswerelow(<6%).MeasurementsforCO2generationfromthedecompositionofHCO3–showedthatelevatedtemperatureandhighHCO3–concentrationstronglypromotedthisprocess.Theseresultssuggestedthatthein-situproducedCO2fromthedecompositionofHCO3–wasprobablytheelectroactivespeciesintheelectrochemicalreductionofHCO3–withoutCO2bubbling.ChangesoftheGibbsfreeenergy,rateconstant,andactivationenergyofthedecompositionofHCO3–intoCO2werealsoinvestigatedandcalculatedfromtheexperimentaldata.

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  • 简介:Two-dimensionalatomic-layeredmaterialisarecentresearchfocus,andsinglelayerTa2O5usedasgatedielectricinfield-effecttransistorsisobtainedviaassembliesofTa2O5nanosheets.However,theelectricalperformanceisseriouslyaffectedbyelectronicdefectsexistinginTa2O5.Therefore,spectroscopicellipsometryisusedtocalculatethetransitionenergiesandcorrespondingprobabilitiesfortwodifferentchargedoxygenvacancies,whoseexistenceisrevealedbyx-rayphotoelectronspectroscopyanalysis.SpectroscopicellipsometryfittingalsocalculatesthethicknessofsinglelayerTa2O5,exhibitinggoodagreementwithatomicforcemicroscopymeasurement.NondestructiveandnoncontactspectroscopicellipsometryisappropriatefordetectingtheelectricaldefectslevelofsinglelayerTa2O5.

  • 标签: TA2O5 电气性能 单层 缺陷 二维 电子能谱分析