Optimal period for diffraction gratings recorded in polymer dispersed liquid crystals

New diffusion model of recording diffraction gratings in the media of PDLC is described in which besides diffusion of monomer molecules also diffusion of polymer molecules and non-locality of diffusion coefficient are taken into account. It lets us to explain why diffraction efficiency is low for low and high values of intensities of grating recording beam. With the considered model, we have theoretically got optimal period for grating recording.     

QUANTITATIVE EXPLANATION ON STRUCTURE-CARCINOGENIC ACTIVITY RELATIONSHIP OF AROMATIC AMINES BY DI-REGION THEORY

Di-region theory, the theory for the mechanism of carcinogenesis, has been extendedsuccessfully on the quantitative Structure-carcinogenic activity relationship (QSCAR) of 63aromatic amines. A quantitative equation for the QSCAR of aromatic amines has been estab-lished by the mechanism conception of the specialized di- functional alkylation between thenitrenium ion of the amino group and the epoxide of the aromatic ring. The agreementbetween calculation and experiment comes up to 98%. Thus, it can now express the puzzlingvariation of the carcinogenicity of aromatic amines, as a comprehensible structure-chemicalreactivity relationship.     

基于不同竞争状况的威斯通并购估价模型研究

本文首先根据收益增长率等于再投资额与再投资收益率的乘积这一基本结论,对超常增长而后无增长的威斯通模型作了一点修正;接着分析了该模型中隐含的企业总投资资本利润率;最后根据微观经济学理论探讨了企业在无增长阶段可能面临的不同竞争状况对其未来盈利能力和现金流的影响,建立了更具普遍性的估价模型.     

Determinants of Triangular Matrices and Trajectories on Ferre Diagrams

Some functions defined on the set of integer triangular matrices and their modifications are considered. These functions are analogs of the classical determinant and permanent functions and provide a powerful apparatus for studying sequences generated by linear recursive equations. Modifications of these functions are used to solve the problem about trajectories on Ferre diagrams and to establish new combinatorial identities.     

用于ICF驱动器的取样光栅的矢量分析与计算

 在ICF的终端光学聚焦系统中，采用取样光栅(BSG)将透射的三倍频光按一定比例送入能量计中进行能量诊断。本文采用精确耦合波矢量分析方法分析了衍射效率与光栅周期、刻槽深度、占空比等的关系，为光栅的实际制作提供了一些有意义的结果。     

莫阿光纤光栅的光谱特性及其在光分插复用器中的应用

从耦合模理论出发，结合莫阿光纤光栅的结构特性，运用分段均匀和传输矩阵法对幕阿光纤光栅的光谱特性进行了理论分析和数值计算；详细研究了线性啁啾莫阿光纤光栅的滤波特性，在此基础上，提出了一种新型的基于线性啁啾莫阿光纤光栅的光分插复用器的结构设计方案。     

颗粒浓度及粒度的光散射在线测量

介绍一种在线监测颗粒浓度及粒度变化的光散射方法。着重提出消除观察窗玻璃污染物对测量结果影响的办法。给出了部分现场实测结果。     

Apparent molar volumes of crown ether complexes in several solvents at 25°C. An estimation of ionic electrostriction

The apparent molar volumes of equimolar concentrations of 18-crown-6-ether (CE) or dibenzo-18-crown-6-ether (B₂CE) and MCl (M=Na, K, or Cs) or MI in dilute solutions of anhydrous methanol, acetonitrile and dimethylsulfoxide have been calculated from density data measured at 25°C. After extrapolation to infinite dilution these results together with the apparent molar volumes of the crown ethers and the alkali metal halides were used to calculate the limiting partial molar volume change for the formation of the complexes. By noting that the charge of the complexed cation has been shown to be completely shielded from the solvent, the volume of complexation can be assumed to be a good estimation of the volume change due to electrostriction of the solvent by the cationic charge. The results are compared to the predictions of the Hepler equation.Presented at the Symposium on Electrochemistry and Spectroscopy of Solutions, Honoring Johannes Coetzee, University of Pittsburgh, November 30, 1989.On leave from Rhodes University, Grahamstown, South Africa.     

紫外写入光纤光栅用亚μm相位掩模板制作误差容限分析

本文采用电磁波标量衍射理论研究了紫外写入光纤光栅用亚μｍ相位掩模的近场衍射特性，并据此得出了零级衍射抑制的条件，２数值模拟方法研究了相位掩模制作误差对有衍射抑制的影响，分析表明，为使零级衍射效率小于５％，相位掩模的刻槽深度和占空比制作误差必须控制在／△ｈ／〈３８ｎｍ和／△ｆ／〈０．１１的范围内。     

几种常用滤波器的特性

对几种滤波器的原理、特性和应用进行了研究比较 ,并特别介绍了目前的研究热点 :各种光纤光栅滤波器及集成阵列波导滤波器等。如今滤波器的蓬勃发展表明 ,它将在未来的光通信系统中发挥越来越重要的作用。