学科分类
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29 个结果
  • 简介:Li4Ti5O12(LTO)/carbonnanotubes(CNTs)compositematerialissynthesizedbasedonasolid-statemethodbysand-milling,spray-dryingandcalciningat8508CunderN2flow.TheLTO/CNTssampleswith1wt%and3wt%weightratioofCNTsadditionandthepristineLTOsampleareprepared.TherateperformanceandthethermalstabilityofthesesamplesareinvestigatedbasedonLiMn2O4(LMO)/LTOfull-cell.TheresultsshowthattheweightratioofCNTsadditionhasdistincteffectonLTOperformances.ThecompositematerialsofLTOcompositedCNTshavebetterperformanceathigh-rateduetotheintercalationenhancementbyconductivenetworkofCNTs.Atsecond,theoverchargingtemperatureresponseofthecell’ssurfacewith1wt%CNTsadditionisthelowest.Theparticlesizedistributionismeasuredandthemostuniformparticlesareobtainedwith1wt%CNTsaddition.ThistrendcouldexplainthatthemediumquantityofCNTsisoptimaltoimprovetheheatandmasstransferandpreventtheproblemsofcrystallitegrowinginterferenceandaggregationduringthecalcinationprocess.

  • 标签: 下线 服务 迁移
  • 简介:采用sol-gel方法在石英玻璃衬底上制备出α轴取向的多晶Bi4Ti3O12(BIT)薄膜,根据透射谱曲线得到薄膜样品的线性折射率为2.35,线性吸收系数为9.81×10^3cm^-1,光学带隙宽度为3.60eV。以脉宽300fs,波长800nm的钛蓝宝石脉冲激光为光源,利用单光束Z-scan技术测得薄膜样品的双光子吸收系数为100.31GW·cm^-2,三阶非线性折射率为-1.02×10^2GW·cm^-2。实验结果表明,所制备的BIT铁电薄膜具有大的非线性光学系数,适合应用于光子器件的制备。

  • 标签: BI4TI3O12 铁电薄膜 Z-SCAN 三阶非线性光学
  • 简介:AKerr-lens,mode-lockedYVO4∕Nd:YVO4lasercoupledwithanacousto-opticmodulator(AOM)Q-switchingnear1064nmwasemployedtopumpanintracavityKTiOPO4(KTP)opticalparametricoscillator.Asubnanosecondsignalwavenear1572nmwithlowrepetitionratewasrealized.AtanAOMrepetitionrateof8kHz,themaximumoutputpowerwas165mW.Thehighestaveragepulseenergy,theshortestduration,andthehighestpeakpowerofamode-lockingsignalpulsewereestimatedtobe~10.3μJ,~120ps,and~82kW,respectively.

  • 标签:
  • 简介:用单辊甩带法制备了不含高生物毒性元素的Ti60Zr10Ta15Si15非晶薄带,并在高于其晶化开始温度的不同温度下对该非晶薄带进行了真空退火,研究了该非晶薄带在磷酸盐缓冲溶液(PBS)中的电化学腐蚀行为及热处理对其显微组织及其电化学行为的影响。结果表明,用单辊甩带法制备的Ti60Zr10Ta15Si15金属薄带为完全的非晶态结构,其玻璃转变温度和晶化开始温度分别为759K和833K,经过878K真空热处理后,薄带发生了部分晶化,在非晶的基底上析出了Ti相;经过938K热处理后,薄带发生了完全晶化,晶化相主要由Ti、Si3Ta5和SiZr以及TiSi组成。动电位极化测试表明,该非晶合金在PBS溶液中可表现出较为优异的耐蚀性能,部分晶化可进一步提高该合金的耐蚀性能,而完全晶化的合金抗腐蚀性能明显下降。

  • 标签: 钛基非晶合金 晶化 电化学腐蚀
  • 简介:4-(Succinimido)-1-butanesulfonicacidasanefficientandreusableBronstedacidcatalyzedthesynthesisofpyrano[4,3-b]pyranderivativesundersolvent-freeconditions.Thecatalystcanbepreparedbymixingsuccinimideand1,4-butanesultonethatismoresimpleandsaferthanthepreparationofsuccinimidesulfonicacid.Thismethodhastheadvantagesofhighyield,cleanreaction,simplemethodologyandshortreactiontime.Thecatalystcouldberecycledwithoutsignificantlossofactivity.

  • 标签: 吡喃衍生物 琥珀酰亚胺 无溶剂条件 酸催化剂 亚胺基 磺酸
  • 简介:Isochronousmassspectrometry(IMS)instorageringsisapowerfultoolformassmeasurementsofexoticnuclewithveryshorthalf-livesdowntoseveraltensofmicroseconds,usingamulticomponentsecondarybeamseparatedin-ightwithoutcooling.However,theinevitablemomentumspreadofsecondaryionslimitstheprecisionofnuclearmassesdeterminedbyusingIMS.

  • 标签: Isochronous MASS SPECTROMETRY
  • 简介:CO2methanationhasbeenahottopicbecauseofitsimportantapplicationinthespacecraftandpotentialutilizationofcarbondioxide.Nickelcatalystisactiveforthisreaction.However,itsactivitystillneedstobeimproved.Dielectricbarrierdischarge(DBD)plasma,initiatedatambientconditionandoperatedat~150°C,hasbeenemployedinthisworkfordecompositionofnickelprecursortoprepareNi/MgAl2O4.Theplasmadecompositionresultsinhighdispersion,uniquestructure,enhancedreducibilityofNiparticlesandpromotedcatalyst-supportinteraction.AnimprovedactivityofCO2methanationwithahigheryieldofmethanehasbeenachievedovertheplasmadecomposedcatalyst,comparedtothecatalystpreparedthermally.Forexample,themethaneyieldoftheplasmapreparedcatalystis71.8%at300°Cbutitis62.9%overthethermalpreparedcatalyst.ThecatalystcharacterizationconfirmedthatCO2methanationovertheDBDplasmapreparedcatalystfollowspathwayofCOmethanation.

  • 标签: 甲烷化反应 分解催化剂 等离子体 二氧化碳 镍催化剂 介质阻挡放电
  • 简介:Alinear4-nodequadrilateralquasi-conformingplaneelementwithinternalparametersisproposed.Theelementpreservesadvantagesofthequasi-conformingtechnique,includinganexplicitstiffnessmatrix,whichcanbeappliedtononlinearproblems.Theweakpatchtestguaranteestheconvergenceoftheelement.ThenthelinearelementisextendedtothegeometricallynonlinearanalysisintheframeworkofTotalLagrangian(TL)formulation.Thenumericaltestsindicatethatthepresentelementisaccurateandinsensitivetomeshdistortion.

  • 标签: 下线 服务 迁移
  • 简介:TheinfluenceofNa2SO4ontheformationofZnOwhiskerswasinvestigatedinthispaper.ZnOwhiskerswithaspectratiosofupto50weresynthesizedbydissolvingε-Zn(OH)2precursorinNaOH/Na2SO4solutionatroomtemperature,followedbyagingoftheresultingsolutionat140℃for6h.Fouriertransforminfraredspectroscopy,Ramanspectroscopy,andX-rayphotoelectronspectroscopyanalysesrevealedthatSO42-ionswereprimarilyadsorbedonthe(100)planeoftheZnOwhiskersviaanouter-spherecomplexconfiguration(O-H…O),therebypromotingtheone-dimensionalgrowthofZnOwhiskersalongthec-axis.

  • 标签: 氧化锌晶须 硫酸钠溶液 水热合成 X射线光电子能谱分析 傅立叶变换红外光谱 ZnO晶须
  • 简介:Toeffectivelysolvetheagglomerationproblemsinthesolidstatereactionprocess,pre-addingglucoseisadoptedtothesynthesisofLiFePO4/CenergymaterialsusingFe–Pwasteslag.Theaverageparticle&grainsizeofLiFePO4/Cdecreases,andtheimpuritiesinLiFePO4/Ccompositesreducetoagreatextent.Itmakesgreatsensetothemassindustrialproduction.Theoptimumsynthesisconditionsdeterminedinthisworkarebasedontheorthogonalexperiments.Thesamplessynthesizedinascaleof500gexhibithighpurity,excellentelectrochemicalperformance,highreactionactivity,goodreversibility,andlowpolarizationlevel.Thedischargecapacitiesare145,134,117,and102mAh/gatthecurrentdensitiesof0.1C,0.2C,0.5Cand1C,respectively.ThisworkputsforwardapracticalsuggestionformassproducingenvironmentalbenignandlowcostLiFePO4/Cascathodematerialsoflithiumionbatteries.

  • 标签: 材料使用 工业生产 磷渣 能源 最佳合成条件 锂离子电池
  • 简介:Amolybdenumdisulfide(MoS2)saturableabsorberwasfabricatedbythermallydecomposingtheammoniumthiomolybdate.ByusingtheMoS2absorber,acompactdiode-pumpedpassivelyQ-switchedTm:GdVO4laserhasbeendemonstrated.AstableQ-switchedlaserwithrepetitionratesfrom25.58to48.09kHzwasachieved.Maximumaverageoutputpowerwas100mWwiththeshortestpulsedurationof0.8μs.Maximumpulseenergyis2.08μJatcenterof1902nm.

  • 标签:
  • 简介:Weexperimentallydemonstratedadiode-pumpedKerr-lensmode-lockedfemtosecondlaserwithaYb:CaYAlO4crystalasthegainmedium.Pulsedurationasshortas33fswasobtaineddirectlyfromtheoscillatoratarepetitionrateof115MHz.Thecentralwavelengthwasat1059nmwithaspectralbandwidthof49nm.Theseare,tothebestofourknowledge,theshortestpulsesgeneratedfromaYb:CaYAlO4oscillator.

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  • 简介:对制造的单mesa终端4H-SiCPIN二极管,采用数值仿真和测试结果比对的方法,分析了各向异性迁移率效应对4H-SiCPIN二极管正向直流特性的影响。详细阐述了器件的正向直流仿真物理模型和参数选取,其中,迁移率的各向异性关系是在各向同性迁移率模型的基础上引入的,载流子寿命采用空间赋值的方法代入模型进行计算。对比结果显示,采用各向同性迁移率模型的仿真结果与实验值偏差较大,对迁移率模型进行各向异性修正后,仿真结果与实验结果符合得较好。研究表明,实际制造的4H-SiCPIN二极管在直流开态下,存在迁移率的各向异性效应。

  • 标签: 4H-SIC PIN二极管 正向直流特性 数值仿真 各向异性迁移率
  • 简介:在这研究,新奇的分子地印的开的多孔的膜(MIOPM)为甲基4-hydroxybenzoate(M4HB)的选择吸附和分离用皮克林抱起对方的大腿把他摔倒模板方法和分子的印技术作好准备。模板M4HB,功能的单体,crosslinker和plastifier2-ethylhexylacrylate(2-EHA)在油阶段被包含。恐水病的硅石nanoparticles(HNP-SiO2)作为stabilizer被采用与nonionic表面活化剂sorbitantrioleate(跨度85)建立稳定的W/O皮克林抱起对方的大腿把他摔倒。SEM和FTIR的结果显示最佳的MIOPM成功地被准备并且拥有了开、互连的毛孔。然后,MIOPM为M4HB被用作吸着剂。关联系数(为Langmuir-Freundlich等温线模型和pseudo-second-order的R2)价值运动模型适合到吸附平衡和运动数据都分别地比0.95高。最大的吸附能力和为MIOPM4的快速的吸附的时间是4.146 ;mg ;g−1和100 ;min分别地。另外,为与在结构上相比的M4HB的MIOPM的渗透分离因素联系了模拟甲基2-hydroxybenzoate(M2HB)能到达3.122。

  • 标签: 对羟基苯甲酸甲酯 分子印迹技术 吸附分离 多孔膜 丙烯酸2-乙基己酯 非离子表面活性剂