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500 个结果
  • 简介:Todemonstratetheviabilityofsteady-statetokamakoperationinahighperformanceregime,whichisoneofthekeyphysicsissuesforaviableeconomicfusionreactor,thequasi-stationaryreversedshear(RS)modeofoperationintheHL-2AtokamakhavebeenmodeledwiththeTRANSPcode.InordertosustaintheRSoperationtowardssteady-state,off-axiscurrentdrivewithlowerhybrid(LH)waveat2.45GHzisusedtocontrolthecurrentprofile.

  • 标签: 混合波 翻转磁性剪切 等离子体 加速器
  • 简介:AnapplicatiopnoftheopticalpyrometerisstudiedformeasuringmonochromaticemissivitiesofcementclinkerwithvariousFe2O3contnet.Theidsaofusing“brightnesstemperature”isintroducedintotheeimssivitymeasurement.Inthismethod,thereisnoneedformeasuringanactualtemperatureofsamplesurfaces,onlywithdeterminingbothbrightnesstemperaturesofasampleandablackbodycantherequiredemissivitybeevaluatedaccordingtoWien'sradiationlaw.Inpractice,thecementclinkerisregardedasagreybody,themonochromaticemissivityisapproximatelyequaltothetotalemissivity,soasingle-colouropticalpyrometerisappliedforthispurpose,Testmeasurementsarecarriedouton10kindsofcementclinkers,Experimentaldataaretreatedbytheleastsquaremethod.Asaresult,theemissivityvariationwithtemperatureatacertainFe2O3contentisquitewellrepresentedbyεn=a+bT.Furthermore,thisworkfirstreportedthattheeimissivitiesofcementclinkerchangeconsierablywithFe2O3contents.Inmultiplecementproductionthisconclusionisveryimportant.

  • 标签: 单色发射 水泥 Fe2O3水泥
  • 简介:Ithasbeenproposedthatfusionreactionsbetweenneutron-richlightnuclei,forexample24C,24Oand28Ne,maycontributetoachievingtheignitiontemperatureforexplosivecarbonburningprocessduringsuperbusrsts[1,2].Studiesoffusionreactionsinvolvingneutron-richnucleiarebeyondordinaryexperimentaltechniques,sincetheintensityofradioactivebeambecomelowforthesemeasurements[3].TheactivetargettechniqueusingTPC(TimeProjectionChamber),withpropertiesofmulti-sampling,highefficiencyandlowbackground,isasuitablesolutiontotheproblem.

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  • 简介:Unlikeorganic–inorganichybridperovskites,all-inorganiccesiumleadhalideperovskitesholdgreatpromisefordevelopinghigh-performanceoptoelectronicdevices,owingtotheirimprovedstability.Herein,weinvestigatetheperovskite-relatedCsPb2Br5nanoplatelets(NPLs)withtunableemissionwavelengthsviachangingthereactiontemperaturesto100°C,120°C,and140°C.ReactiontemperatureplaysakeyroleindeterminingtheshapesandthicknessesoftheresultingCsPb2Br5NPLs.AhighertemperatureisinfavoroftheformationofsmallerandthickerNPLs.Todeveloptheirpotentialapplicationsinoptoelectronicdevices,greenlightemittingdiodes(LEDs)andphotodetectorsbasedonCsPb2Br5NPLsarefabricated.ThegreenLEDsbasedonCsPb2Br5NPLssynthesizedat140°Cexhibitanexcellentpuregreenemission(fullwidthathalf-maximumof<20nm)anddisplayaluminousefficiencyof34.49lm∕Wunderanoperationcurrentof10mA.Moreover,thephotodetectorbasedonCsPb2Br5NPLssynthesizedat100°Chasbetterperformancewitharisetimeof0.426s,adecaytimeof0.422s,andaratioofthecurrent(withandwithoutirradiation)of364%.

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  • 简介:Entangledphotonsarethefundamentalresourceinquantuminformationprocessing.Howtoproducethemefficientlyhasalwaysbeenamatterofconcern.HereweproposeanewwaytoproducecorrelatedphotonsefficientlyfrommonolayerWS2basedonboundstatesinthecontinuum(BICs).TheBICsofradiationmodesinthemonolayerWS2arerealizedbydesigningthephotoniccrystalslab-WS2-slabstructure.Thegenerationefficiencyofcorrelatedphotonpairsfromsuchastructurehasbeenstudiedbyusingarigorousquantummodelofspontaneousparametricdown-conversionwiththeplanewaveexpansionmethod.ItisfoundthatthegenerationefficiencyofcorrelatedphotonpairsisgreatlyimprovedifthesignalandidlerfieldsarelocatedattheBICsdeterminedbytheinversescatteringmatrixofthestructure.Thisisincontrasttotheparametricdown-conversionprocessfortheenhancedgenerationofnonlinearwavesifthepumpfieldislocatedattheBICsdeterminedbythescatteringmatrixofthestructure.Thegenerationrateofthecorrelatedphotonpairscanbeimprovedby7ordersofmagnitudeinsomedesignedstructures.Thegeneratedquantumsignalsaresensitivetothewavelengthandexhibitnarrowedrelativelinewidth,whichisverybeneficialforquantuminformationprocessing.

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  • 简介:Inthispaper,thevariableseparationapproachisusedtoobtainlocalizedcoherentstructuresofthe(2+1)-dimensionalgeneralizedDavey-Stewarsonequations:iqt+1/2(qxx+qyy)+(R+S)q=O,Rx=-σ/2|q|2ySy=-σ/2|q|2/x.ApplyingaspecialBacklundtransformationandintroducingarbitraryfunctionsoftheseedsolutions,anabundanceofthelocalizedstructuresofthismodelisderived.Byselectingthearbitraryfunctionsappropriately,somespecialtypesoflocalizedexcitationssuchasdromions,dromionlattice,breathers,andinstantonsareconstructed.

  • 标签: 非线性偏微分方程 Darey-Stewa-Son方程 相干孤子结构
  • 简介:怪物状态在1D数组被学习了,并且许多不同怪物状态用不同模型被发现了。研究最近被扩大了到2D数组,但是仅仅到他们的阶段模型。这里,我们把它递非局部的联合的影响上的神经原和焦点的2D数组的一个nonphase模型。用广泛的数字模拟,令人惊讶地,我们发现这个系统能显示出以前观察的怪物状态的大多数类型,与以前的模型相对照,在怪物状态的仅仅或一些类型能在每个模型被观察的地方。我们也发现这个模型能显示出象gridding那样的一些特殊像怪物的模式和multicolumn模式,它以前仅仅在阶段模型被观察。进一步,我们在场一条有效途径,即,移开联合的一些连接,产生异构的联合,它导致多样的像怪物的模式并且甚至从一个像怪物的模式导致转变到另外一个。

  • 标签: 神经元模型 局部耦合 二维阵列 嵌合体 体模 多样性
  • 简介:Thegreenlong-after-glowluminescencefromTb3+-dopedSr2SiO4phosphors,whicharesynthesizedbythehightemperaturesolidstatereactioninareductiveatmosphere,isobservedinthispaper.Theresultsshowthatunderultravioletexcitation,theobtainedphosphorsproduceanintensegreen-lighting-emissionfromtheTb3+,andthegreen-lightinglongafter-glowluminescencerelatedtoTb3+canlasthalfanhouraftertheirradiationsourcehasbeenremoved.Moreover,theeffectsofco-dopingLi+,Dy3+,Er3+,Gd3+,andYb3+withTb3+onthedecaypropertiesandthermoluminescencepropertiesareinvestigatedtoconfirmthelong-after-glowmechanism.

  • 标签: 长余辉发光 铽掺杂 固相反应合成 绿色照明 还原性气氛 衰变性质
  • 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:ThepresolarSiCgrains[1]carrytheoriginalstellarnucleosynthesissignature.Theirisotopicanomaliescomparedtothesunarethestrongconstrainsinthesupernovae(SN)modelcalculations.The15N-excessinsomeSiC-ABgrains(12C/13C<10and14N/15N<272)isoneofthechallengesofcore-collapsesupernovae(CCSNe)models[2].Recently,PignataripointedoutthattheentrainmentofH-richmaterialintotheHeshellbeforetheSNexplosionallowsthecoproductionof13C,15Nand26Al,whichprovidesanewproductionscenarioforSiC-ABgrains[2].IntheHeshellnucleosynthesis,the13Cisproducedthrough12C(p,γ)13N(β+γ)13Creaction.The14Nissynthesizedthrough13N(n,γ)and13C(p,γ)reactions.

  • 标签: EXPERIMENTAL STRONG SIC SUN 15N He
  • 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