Synthesis of Novel Monomeric Dyes with Anthraquinone Residue

Two novel polymerizable dyes with anthraquinone residue have been prepared, and their structures were characterized by FTIR, ^1HNMR and EA.     

金纳米粒子光学性质中的尺寸和形状效应

纳米尺度的金属及半导体呈现出特殊的光学、电学及磁学性质,采用近年发展起来的离散偶极近似(DDA)的方法,我们分析了金纳米粒子的尺寸及形状对其光学性质的影响。粒子周围介质的影响在文中亦作了分析。计算结果显示,金纳米粒子的等离子体吸收带同时受到粒子尺寸和形状的影响,但来自形状的影响更为明显。与米氏理论及扩展的甘氏理论相比较,DDA方法在粒子尺寸不再远小于入射光波长的时候更准确,并能应用于任何形状的纳米粒子。理论计算与实验结果能较好的吻合。     

Spectra Analysis of a Novel Ti-Doped LiAlO2 Single Crystal

LiAlO2 single crvstals doped with Ti at concentration 0.2at.% are grown by the Czochralskl technique with dimensions φ42×55mm. Ti ions in the crystal are quadrivalence proven by comparing the absorption and fluorescence spectra of pure LiAlO2 and Ti： LiAlO2. After air and Li-rich atmosphere annealing, the absorption peaks in the range of 600-800nm disappear. We conclude that 682 and 756nm absorption peaks are attributed to the VLi and Vo absorptions, respectively： The peaks at 716nm and 798nm may stem from the VLi^＋ and absorptions. The colour-centre model can be applied to explain the experimental phenomena. Ti^4＋-doping produces more lithium vacancies in the LiAlO2 crystal. The intensities of [LiO4] and the associated bonds remain unchanged, which improves the anti-hydrolyzation and thermal stability of LiAlO2 crystals.     

Additive Maps Preserving Nilpotent Operators or Spectral Radius

Let X be a （real or complex） Banach space with dimension greater than 2 and let B0（X） be the subspace of B（X） spanned by all nilpotent operators on X. We get a complete classification of surjective additive maps Ф on B0（X） which preserve nilpotent operators in both directions. In particular, if X is infinite-dimensional, we prove that Ф has the form either Ф（T） = cATA^-1 or Ф（T） = cAT＇A^-1, where A is an invertible bounded linear or conjugate linear operator, c is a scalar, T＇ denotes the adjoint of T. As an application of these results, we show that every additive surjective map on B（X） preserving spectral radius has a similar form to the above with ｜c｜ = 1.     

Gain Spectrum in an Asymmetric Double Quantum Well

We propose a scheme for light amplification in an asymmetric double quantum well, where two excited states are coupled by resonant tunnelling through a thin barrier in a three-level system of electronic subbands. By applying a single driving laser, the steady state gain can be obtained. The calculated gain spectrum for an asymmetric GaAs/AlGaAs double quantum well structure was presented.     

一种可实时化的多光谱图像融合系统

在多光谱摄影和光电成像技术基础上，本文提出了一种可实时化的多光谱图像融合系统。与多光谱摄影相比，不仅可实现多光谱实时化摄像，而且光谱响应进一步向近红外延伸，并引入图像处理技术。实验表明：这种技术对于增加系统的识别能力具有明显的作用，可进一步构成不同用途的新型多光谱图像融合系统。     

碱土金属氟卤化物中的Eu3+的荧光光谱特征

本文系统研究了MFX体系中Eu³⁺荧光光谱特征,着重讨论了X^-,M²⁺及杂质缺陷(主要为O^2-)对Eu³⁺发光的影响.     

N_2和O_2纯转动拉曼光谱(PRRS)的温度特性

计算了N2 和O2 的PRRS ,讨论了其温度特性。提出通过测量N2 和O2 的PRRS计算大气温度的方法。     

防紫外线伞ATR-OMNI采样器的FTIR分析

本实验使用OMNI采样器，直接对伞面内外进行单反射ATR的分析，快速、简便、不破坏样品，得到分辨率很好的红外图谱，再配合红外谱库的谱图检索，可以分别得到匹配率95％以上的尼龙－6和聚酯型聚氨酯的分析结果。