学科分类
/ 6
103 个结果
  • 简介:利用集成电路芯片结合光敏晶体管等器件设计并成功制作了一种自动化测量的干涉条纹计数仪器,以实现干涉条纹的自动测量、可逆计数显示等功能.设计方案包括基于光敏晶体管RPM-075PT获取光电信号,以集成电路ST288A准确判别干涉条纹的凹进冒出方向以反映等厚或等倾干涉中光程的变化情况,使用集成电路ICM7217A进行条纹可逆计数.进一步的,使用自带整形滤波功能芯片ST288A以简化方向判别电路及提高抗干扰能力.最后,实验测试结果表明本计数器全面满足干涉条纹的计数要求,可取代人工观测条纹计数,可广泛应用于高校实验、企业检测等应用干涉条纹计数的场景中.

  • 标签: 光敏晶体管 干涉条纹 可逆计数
  • 简介:Theeffectofbismuth(Bi)forbothVO2+/VO2+andV3+/V2+redoxcouplesinvanadiumflowbatteries(VFBs)hasbeeninvestigatedbydirectlyintroducingBionthesurfaceofcarbonfelt(CF).TheresultsshowthatBihasnocatalyticeffectforVO2+/VO2+redoxcouple.Duringthefirstchargeprocess,BiisoxidizedtoBi3+(neverreturnbacktoBimetalinthesubsequentcycles)duetothelowstandardredoxpotentialof0.308V(vs.SHE)forBi3+/BiredoxcouplecomparedwithVO2+/VO2+redoxcoupleandBi3+exhibitno(orneglectable)electro-catalyticactivity.Additionally,therelationshipbetweenBiloadingandelectrochemicalactivityforV3+/V2+redoxcouplewasstudiedindetail.2wt%Bi-modifiedcarbonfelt(2%-BiCF)exhibitsthehighestelectrochemicalactivity.Usingitasnegativeelectrode,ahighenergyefficiency(EE)of79.0%canbeachievedatahighcurrentdensityof160mA/cm2,whichis5.5%higherthanthepristineone.Moreover,theelectrolyteutilizationratioisalsoincreasedbymorethan30%.Eventhecelloperatedat140mA/cm2forover300cycles,theEEcanreach80.9%withoutobviousfluctuationandattenuation,suggestingexcellentcatalyticactivityandelectrochemicalstabilityinVFBs.

  • 标签:
  • 简介:Weproposeandexperimentallydemonstratea2×2thermo-optic(TO)crossbarswitchimplementedbydualphotoniccrystalnanobeam(PCN)cavitieswithinasilicon-on-insulator(SOI)platform.Bythermallytuningtherefractiveindexofsilicon,theresonancewavelengthofthePCNcavitiescanbered-shifted.WiththehelpoftheultrasmallmodevolumesofthePCNcavities,only~0.16mWpowerisneededtochangetheswitchingstate.Withaspectralpassbandof0.09nmatthe1583.75nmoperationwavelength,theinsertionloss(IL)andcrosstalk(CT)performancesweremeasuredasIL(bar)=-0.2dB,CT(bar)=-15dB,IL(cross)=-1.5dB,andCT(cross)=-15dB.Furthermore,thethermaltuningefficiencyofthefabricateddeviceisashighas1.23nm/mW.

  • 标签:
  • 简介:Theneworganic-inorganiccompound,[C_6H_7N_2O_2]_3TeCl_5·2Clwassynthesizedanditsstructurewasdeterminedatroomtemperatureinthetriclinicsystem(P~-1)withthefollowingparameters:a=10.5330(11)?,b=10.6663(11)?,c=15.9751(16)?,α=82.090(2)°,β=71.193(2)°,γ=68.284(2)°andZ=2.ThefinalcycleofrefinementledtoR=0.057andRw=0.149.ThecrystalstructurewasstabilizedbyanextensivenetworkofN--H···Clandnon-classicalC--H···Clhydrogenbondsbetweenthecationandtheanionicgroup.Severalthermalanalysistechniquessuchasthermogravimetricanalysis,differentialscanningcalorimetricanalysisandevolvedgasanalysiswereused.Weusedisoconversionalkineticsmethodstodeterminethekineticsparameters.Weobservethatthedecompositionof[C_6H_7N_2O_2]_3TeCl_5·2Clentailstheformationhydrochloricacidofnitroanilineasvolatiles.Theinfraredspectrawererecordedinthe4000–400cm~(-1)frequencyregion.TheRamanspectrawererecordedintheexternalregionoftheanionicsublatticevibration50–1500cm~(-1).TheopticalbandgapwascalculatedfromtheUV-VisabsorbancespectrausingclassicalTaucrelationwhichwasfoundtobe3.12and3.67eV.

  • 标签: 结构分析 光学性质 合成 化合物 紫外-可见吸收光谱 差示扫描量热分析
  • 简介:Thispapercontainsadetailed,selfcontainedandmorestreamlinedproofofthel~2decouplingtheoremforhypersurfacesfromthepaperofBourgainandDemeterin2015.TheauthorshopethiswillserveasagoodwarmupforthereadersinterestedinunderstandingtheproofofVinogradov'smeanvaluetheoremfromthepaperofBourgain,DemeterandGuthin2015.

  • 标签:
  • 简介:Mode-andpolarization-divisionmultiplexingoffernewdimensionstoincreasethetransmissioncapacityofopticalcommunications.Selectiveswitchesarekeycomponentsinreconfigurableopticalnetworknodes.Anon-chipsilicon2×2mode-andpolarization-selectiveswitchthatcanroutefourdatachannelsontwomodesandtwopolarizationssimultaneouslyisproposedandexperimentallydemonstratedforthefirsttime,tothebestofourknowledge.Theoverallinsertionlossesarelowerthan8.6dB.Toreducetheinter-modalcrosstalk,polarizationbeamsplittersareaddedtofiltertheundesiredpolarizationsormodes.Themeasuredinter-modalandintra-modalcrosstalkvaluesarebelow-23.2and-22.8dBforallthechannels,respectively.

  • 标签:
  • 简介:TheAlkalineThermalTreatment(ATT)ofbiomassisoneofthefewbiomassconversionprocessesthathasapotentialforBECCS(bio-energywithcarboncaptureandstorage).Combiningin-situcarboncapturewithcreatesacarbon-neutralprocessthathasthepotentialtobecarbon-negative.Thisstudyhasshownthattheconversionofcellulosetosuppressedcanbeachievedthroughthereformingofgaseousintermediatesinafixedbedof10%Ni/ZrO2.Reformingoccursatlowtemperatures≤773K,whichcouldallowforimprovedsustainability.

  • 标签:
  • 简介:强壮的苏(2)计量器chromoelectric领域里的费米子粒子对生产以一个古典方法用Boltzmann-Vlasov方程被学习。在古典描述的一个preproduction过程的存在用non-Abelian粒子生产的分发进化被显示出。发现粒子数字密度的分发在二个岛上被集中并且当它演变,在颜色费用范围上显示出一个裂口有趣,最终到达与这个领域的振幅和变化有关的一个稳定的状态。

  • 标签: SU(2) 背景场 BOLTZMANN Vlasov方程 粒子数密度 试制过程
  • 简介:Hydrogen,thecleanestandmostpromisingenergyvector,canbeproducedbysolarintochemicalenergyconversion,eitherbythephotocatalyticdirectsplittingofwaterintoH2andO2,or,moreefficiently,inthepresenceofsacrificialreagents,e.g.,intheso-calledphotoreformingoforganics.Efficientphotocatalyticmaterialsshouldnotonlybeabletoexploitsolarradiationtoproduceelectron–holepairs,butalsoensureenoughchargeseparationtoallowelectrontransferreactions,leadingtosolarenergydriventhermodynamicallyup-hillprocesses.RecentachievementsofourresearchgroupinthedevelopmentandtestingofinnovativeTiO2-basedphotocatalyticmaterialsarepresentedhere,togetherwithanoverviewonthemechanisticaspectsofwaterphotosplittingandphotoreformingoforganics.Photocatalyticmaterialswereeither(i)obtainedbysurfacemodificationofcommercialphotocatalysts,orproduced(ii)inpowderformbydifferenttechniques,includingtraditionalsolgelsynthesis,aimingatengineeringtheirelectronicstructure,andflamespraypyrolysisstartingfromorganicsolutionsoftheprecursors,or(iii)inintegratedform,toproducephotoelectrodeswithindevices,byradiofrequencymagnetronsputteringorbyelectrochemicalgrowthofnanotubearchitectures,orphotocatalyticmembranes,bysupersonicclusterbeamdeposition.

  • 标签:
  • 简介:CO2capturewithionicliquids(ILs)hasattractedmanyattentions,andmostworksfocusedonabsorptionabilityatambienttemperatures,whileseldomresearchwasconcernedatelevatedtemperatures.ThisnotonlylimitstheCO2absorptionapplicationatelevatedtemperature,butalsothedeterminationoftheoperationconditionoftheCO2desorptiongenerallyoccurringathighertemperature.ThisworkmainlyreportedCO2solubilitiesinILsatelevatedtemperaturesandrelatedpropertieswerealsoprovided.1-alkyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide([CnMIm][Tf2N])ILswereselectedasphysicalabsorbentsforCO2captureinthisworkduetotheirrelativehigherCO2absorptioncapacitiesandgoodthermalstabilities.Thelong-termstabilitytestsshowedthat[CnMIm][Tf2N]isthermallystableat393.15Kforlongtime.CO2solubilitiesin[CnMIm][Tf2N]weresystematicallydeterminedattemperaturesfrom353.15Kto393.15K.ItdemonstratedthatCO2solubilityobviouslyincreaseswiththeincreaseofpressurewhileslightlydecreaseswithincreaseoftemperature.Asthelengthofalkylchainonthecationincreases,CO2solubilityinILsincreases.Additionally,thethermodynamicpropertiesincludingtheGibbsfreeenergy,enthalpy,andentropyofCO2werealsocalculated.

  • 标签:
  • 简介:Inthiswork,acidfunctionalizedmulti-wallcarbonnanotubes(MWCNTs)weremodifiedwithimidazolium-basedionicliquids.Theselectiveoxidationofvariousalcoholswithhydrogenperoxidecatalyzedby[PZnMo_2W_9O_(39)]~(5-),ZnPOM,supportedonionicliquids-modifiedwithMWCNTs,MWCNTAPIB,isreported.Thiscatalyst[ZnPOM@APIB-MWCNT],wascharacterizedbyX-raydiffraction,scanningelectronmicroscopy(SEM)andFT-IRspectroscopicmethods.Thisheterogeneouscatalystexhibitedhighstabilityandreusabilityintheoxidationreactionwithoutlossofitscatalyticperformance.

  • 标签: 多壁碳纳米管 离子液体 催化剂 多金属氧酸盐 氧化改性 H2O2
  • 简介:Co-electrolysisofCO2andH2Ousinghigh-temperaturesolidoxideelectrolysiscells(SOECs)intovaluablechemicalshasattractedgreatattentionsrecentlyduetothehighconversionandenergyefficiency,whichprovidesopportunitiesofreducingCO2emission,mitigatingglobalwarmingandstoringintermittentrenewableenergies.AsingleSOECtypicallyconsistsofanionconductingelectrolyte,ananodeandacathodewheretheco-electrolysisreactiontakesplace.Thehighoperatingtemperatureanddifficultactivatedcarbon-oxygendouble-bondofCO2putforwardstrictrequirementsforSOECcathode.Greateffortsarebeingdevotedtodevelopsuitablecathodematerialswithhighcatalyticactivityandexcellentlong-termstabilityforCO2/H2Oelectro-reduction.Thesofarcathodematerialdevelopmentisthekeypointofthisreviewandalternativestrategiesofhigh-performancecathodematerialpreparationisproposed.UnderstandingthemechanismofCO2/H2Oelectro-reductionisbeneficialtohighlyactivecathodedesignandoptimization.Thusthepossiblereactionmechanismisalsodiscussed.Especially,amethodincombinationwithelectrochemicalimpedancespectroscopy(EIS)measurement,distributionfunctionsofrelaxationtimes(DRT)calculation,complexnonlinearleastsquare(CNLS)fittingandoperandoambientpressureX-rayphotoelectronspectroscopy(APXPS)characterizationisintroducedtocorrectlydisclosethereactionmechanismofCO2/H2Oco-electrolysis.Finally,differentreactionmodesoftheCO2/H2OcoelectrolysisinSOECsaresummarizedtooffernewstrategiestoenhancetheCO2conversion.Otherwise,developingSOECsoperatingat300-600°CcanintegratetheelectrochemicalreductionandtheFischer-TropschreactiontoconverttheCO2/H2Ointomorevaluablechemicals,whichwillbeanewresearchdirectioninthefuture.

  • 标签:
  • 简介:Probingtheopticalpropertiesofmolybdenumdisulfide(MoS2)isvitaltoitsapplicationinplasmon-enhancedspectroscopy,catalysts,sensing,andoptoelectronicdevices.Inthispaper,wetheoreticallystudiedtheRamanandfluorescencepropertiesofmonolayerMoS2usingtip-enhancedspectroscopy(TES).Inthestrong-couplingTESsystem,theRamanandfluorescenceenhancementfactorscanbeturnedtoashighas4.5×108and3.3×103,respectively,byoptimizingthetip–MoS2-filmdistance.OurtheoreticalresultsnotonlyhelptodeeplyunderstandtheTESpropertiesofmonolayerMoS2,butalsoprovidebetterguidanceontheapplicationsofthenoveltwo-dimensionalmaterial.

  • 标签:
  • 简介:ReducingtheanthropogenicCO2emissionsfromfossilresourcecombustionandhumanactivitieshasbecomeoneofthemajorchallengeswearefacingtoday.BeyondthosepracticalapplicationsfortheutilizationofCO2,suchasthesynthesisofsalicylicacid,methanol,urea,NaHCO3-Na2CO3chemicalsandrecentlydevelopedpolycarbonatesynthesis,scientistsarestillseekingnewmaterialsandtechnologiesforefficientcapture,

  • 标签:
  • 简介:TheeffortonelectrochemicalreductionofCO2tousefulchemicalsusingtherenewableenergytodrivetheprocessisgrowingfastrecently.Inthisreview,weintroducetherecentprogressesontheelectrochemicalreductionofCO2insolidoxideelectrolysiscells(SOECs).Athightemperature,onlyCOisproducedwithhighcurrentdensitiesandFaradicefficiencywhilethereactoriscomplicatedandabettersealingtechniqueisurgentlyneeded.Thetypicalelectrolytessuchaszirconia-basedoxides,ceria-basedoxidesandlanthanumgallates-basedoxides,anodesandcathodesareintroducedinthisreview,andthecathodematerials,suchasconventionalmetal–ceramics(cermets),mixedionicandelectronicconductors(MIECs)arediscussedindetail.Inthefuture,togainmorevalue-addedproducts,theelectrolyte,cathodeandanodematerialsshouldbedevelopedtoallowSOECstobeoperatedattemperaturerangeof573–873K.Atthosetemperatures,SOECsmaycombinetheadvantagesofthelowtemperaturesystemandthehightemperaturesystemtoproducevariousproductswithhighcurrentdensities.

  • 标签: