简介:Westudyfew-electronsemiconductorquantumdotsusingtheunrestrictedHartree-Fock-RoothaanmethodhasedontheGaussianbasis.Ouremphasisisontheenergylevelcalculationforquantumdots.Theconfinementpotentialinaquantumdotisassumedtobeinaformofthree-dimensionalsphericalfinitepotentialwell.Somevaluableresults,suchastherearrangementoftheenergylevel,havebeenobtained.
简介:Low-dimensionalnanomaterials,owingtotheiruniqueandversatileproperties,areveryattractiveforenormouselectronicandoptoelectronicapplications.PbSquantumdots(QDs),characterizedbyalargeBohrradiusandsize-tunablebandgap,areespeciallyinterestingforphotonicapplicationsinthenear-infraredregion.Here,oleicacidcappedcolloidalPbSQDsasasaturableabsorberareinvestigatedforultrashort-pulsegeneration.ThePbSQDsexhibitoutstandingnonlinearsaturableabsorptionpropertiesat1550nm:amodulationdepthupto44.5%andathermaldamagethresholdlargerthan30mJ∕cm~2.ByincorporatingPbSQDsintoafiberlaser,atransform-limitedsolitonpulseasshortas559fswithabandwidthof4.78nmisrealizedat1563nm.NumerousapplicationsmaybenefitfromthenonlinearsaturableabsorptionpropertiesofPbSQDs,suchasnear-infraredpulsedlasersandmodulators.
简介:WefabricatephotoniccrystalslabmicrocavitiesembeddedwithGaAsquantumdotsbyelectronbeamlithographyanddropletepitaxy.ThePurcelleffectofexcitonemissionofthequantumdotsisconfirmedbythemicrophotoluminescencemeasurement.Theresonancewavelengths,widths,andpolarizationareconsistentwithnumericalsimulationresults.
简介:Nanometer-scaleAuquantumdotshavebeenassembledonSiO2bycontrollingthereactionofrawmatedaistoformacitrateAusolandanaminosilane/dithiol-treatedpatternedSiwafer.Thedetailedformationmechanismhasbeenstudied.Threegoldcolloidalparticles(-15nm),alignedinachaintoformaone-dimensionalcurrentpath,wasbridgedacrossan80-nmgapbetweensourceanddrainmetalelectrodes,ThedeviceexhibitedaCoulombblockadeeffectat33K.
简介:摘要目的探讨DOTS方案在肺结核患者治疗方面的效果。方法将2008年1月至2009年12月间肺结核患者192例列入对照组;将2010年1月至2011年12月间肺结核患者236例列入研究组;对照组患者临床仅采用常规药物治疗,研究组患者在对照组用药基础上运用DOTS方案对患者进行全面的教育和跟踪随访,观察两组患者随访平均阴转时间及用药期间不良反应率。结果研究组成功随访率明显高于对照组,研究组成功随访患者平均阴转时间明显短于对照组,研究组用药期间不良反应率明显低于对照组,数据经统计学比较具有极显著差异(P<0.01)。结论DOTS方案可提高肺结核患者依从性,使更多的患者坚持完成整个治疗过程,达到治愈效果,并提高疗效,加快患者阴转速度,减少不良反应的发生。
简介:Thelabellingandimagingoftumorcellswereinvestigatedviaarginine-glycine-asparticacidcysteine(RGDC)peptide-labelledquantumdots(QDs).TheresultsshowthatRGDCmodifiedQDscanlabelSMMC-7721tumorcellsandadheretocellularmembrane.Inconstrast,theunmodifiedQDsaremainlydispersedaroundthecell.WealsofoundthattheRGDC-QDscanpenetrateintothecellat2hofincubation.After6hofincubation,RGDC-QDscanaccumulateinauniqueintracellularregion.
简介:Here,wereportthesynthesisandcharacterizationsofsol—gelderivedzincoxide(ZnO)quantumdots(QDs)usingzincacetatedihydrate(Zn(CH3COO)2·2H20)andlithiumhydroxidemonohydrate(LiOH·H20)asrawmaterial.Theas-preparedZnOQDswasannealedatdifferenttemperature(400,700,and900℃)andthestructural,opticalpropertieswereinvestigatedbyX-raydiffraction(XRD),highresolutiontransmissionelectronmicroscopy(HRTEM),UV—Visandphotoluminescence(PL)spectroscopy.ThepowderXRDpatternsoftheobtainedsamplesshowedtheformationofsingle-phasewurtzitestructureandthemorphologicalchangeshavebeenobservedwithincreasingannealingtemperature.Intheabsorptionspectra,theopticalbandgapofnanocrystallineZnOQDsdecreasedfrom3.18to3.11eVandtheparticlesizeincreasedwithincreasingtemperature.InthePLspectra,abroadgreenemissionpeakrelatedtodefectlevelsinthevisiblerangeofthespectrahavebeenrecorded.
简介:Grapheneanditsderivativeshaveattractedtremendousresearchinterestbecauseoftheiruniquecompositionandphysicochemicalproperties[1??3].However,thepotentialbiologicaltoxicityofGQDshasbecomeahealthriskbecauseoftheirinherentchemicalcompositionandnanoscaleproperties[4].Zebrafish(Daniorerio)isoneofthemostpromisinginvivomodelsystemsfortoxicitystudies[5].
简介:我们理论上学习准确diagonalization方法与纺纱轨道相互作用(SOI)在联合的量点的InAs平行(CQD)限制的二交往电子的旋转性质。通过汗衫和三位字节混合的导致的纺纱说的SOI,我们为弱、强壮的SOI显示出不同旋转性质。我们在SOI下面调查二个电子的协调汗衫三位字节旋转摆动,并且表明取决于SOI力量,内部点的分离和外部磁场的旋转摆动的详细行为。为了更好理解旋转动力学的内在的物理,我们为弱、强壮的SOI介绍四水平的模型Hamiltonian,并且发现SOI在飞机导致了,有效磁场能是从二电子的刺激精力系列提取的份量上。