【摘 要】
：
The optical and bonding characters of doping ZnSe quantum dots are investigated in this paper in theory and experiment.Cd,Mn and Cu doping ZnSe have been synthesized with good blue or orange luminesce
【机 构】
：
Advanced Photonics Center,School of Electronic Science and Engineering,Southeast University,Nanjing,
论文部分内容阅读
The optical and bonding characters of doping ZnSe quantum dots are investigated in this paper in theory and experiment.Cd,Mn and Cu doping ZnSe have been synthesized with good blue or orange luminescence.In experiment,we have found that Mn and Cu doping ZnSe quantum dots have the same wavelength of absorption spectra with pure ZnSe quantum dots.Cd doping ZnSe quantum dots have different one with ZnSe.Moreover,absorption spectra of Cd-ZnSe quantum dots shift to red with higher speed than those of Cu-ZnSe and Mn-ZnSe.We have thought that it is the different orbitals resulting in this phenomenon.Then,we calculated Molecular Orbital(MO)of these clusters.The calculated results show that doping Cd,Mn and Cu ZnSe quantum dots have different MO.Highest Occupied Molecular Orbital(HOMO)and Lowest Unoccupied Molecular Orbital(LUMO)of Mn belong to range of ZnSe,which caused Mn-ZnSe quantum dots have same wavelength of absorption spectra and different luminescence.LUMO of Cu is in the scope of ZnSe.And HOMO of Cd is in the range of ZnSe.Thus,Cu-ZnSe quantum dots have same wavelength of absorption spectra.Luminescence of ZnSe quantum dots are influenced by Cu.Cd-ZnSe quantum dots have different absorption spectra because Cd has changed the transition of orbital.In this way,Luminescence of Cd-ZnSe are different with ZnSe quantum dots.
其他文献
Herein,for the first time,natural palygorskite powders modified with sulfhydryl groups by nanotexturization method have been systematically studied for further adsorbent selection of soil remediation.
魔芋又称蒟蒻,是我国西部山区重要的经济作物,在中国有两千多年的食用和药用历史,最早见诸于左思曾引起洛阳纸贵的《蜀都赋》,也是目前世界上公认的最好的膳食纤维之一,在日本韩国及欧洲拥有大量的消费人群。魔芋在重金属离子吸附方面的研究已有二十多年的历史[1,2],作为一种可溶性膳食纤维其特性研究一直受到各方面关注。本文设计生产一种基于低温包埋技术的缓溶魔芋葡甘聚糖,溶解性、酶解性、葡甘聚糖含量测定等方面的
我国北方内蒙古等地区有着面积广袤的沙地、沙漠,如何实现沙漠的绿化一直以来都是备受人们关注的难题.许多沙化地区降水较多,有利植物生长,但由于沙子保水性差,水会迅速渗透到土层底部,很难被植物充分利用,因此目前还很难实现大面积的退沙还林.含有羟基等官能团的高吸水性物质吸水膨胀后形成凝胶物质,在干燥条件下又能将水分缓慢释放,有助于增强沙土的含水量并促进植物生长,从而有可能实现沙漠的绿化.我们以高吸水性聚合
脐橙是赣南地区果农广为栽培的高效经济作物,品种多为中熟纽荷尔脐橙,种植面大,产量高.因储藏保鲜技术不当,不少栽培者采后损失严重,造成了很大的经济损失.因而,研制一种材料易得、制备方便、成本低廉,保鲜操作简单、便于果农使用、保鲜效果明显的新型绿色保鲜剂和保鲜技术,对提高脐橙贮藏保存率,增加经济效益和社会效益具有重要意义.本文研制了以壳聚糖为原料,通过化学改性制得水溶性羧甲基壳聚糖[1]为主体的保鲜剂
多功能酶在生命,疾病和其他研究领域非常重要[1-2].然而在酶家族预测中,由于传统单标签预测方法的限制,多功能酶信息不得不从原始数据中剔除.在我们的研究中,为了能够同时预测多家族酶的多个类别,我们将两种多标签学习方法RAk EL-RF、MLKNN和两类蛋白质描述符CTD、PseAAC进行结合,得到了四种预测器.针对于训练集,我们采用十倍交叉验证,四种预测器的准确率分别达到97.99％,96.07％
食品添加剂是指为改善食品品质和色、香、味以及为防腐、保鲜和加工工艺的需要而加入食品的人工合成或者天然物质[1]。它的存在是为了改善食品的感官特性，使得食品更安全和方便被食用。无论是天然食品添加剂还是合成的食品添加剂，本质上都是化合物。食品添加剂信息管理系统是实现合理有效地使用和管理食品添加剂的有效工具。目前，已有的食品添加剂的信息管理系统大多只具有文本检索功能，尚未见具有化学结构检索功能的食品添加
molecular wire necklace.The electronic structures,transportation properties,field and twist effects of the basis unit have been studied in this paper.With the intensity of the electric field increasin
A coordinate mapping discrete variable representation method with the cosine grid basis function is presented to successfully solute electronic Schr(o)dinger equation.In this paper we propose a scheme
The electronic structure and chemical bonding of AnF4(An=Th to Cm)are investigated under constraint of tetrahedral(Td)symmetry by using scalar relativistic density functional theory(DFT).The An-F bond
Very recently,gold nanoparticles supported on TiO2(1.2 mol%)were found to catalyze the cycloisomerization of a series of 1,6-enynes in high yields in 1,2-dichloroethane(DCE).1,2 To our knowledge,there