NASICON型化合物结构的NMR研究

在水热晶化合成一系列NASICON型化合物的基础上,应用固体高分辨³¹P和²⁹Si MAS NMR,研究了几种NASICON化合物的结构,观察其骨架原子P和Si在结构中的状态及分布,并解释了由于在结构中发生取代作用而引起,Si或P的化学位移的变化.     

Wave scattering from dielectric-coated cylinder

The high frequency scattering of TE wave from a dielectric-coated conducting cylinder is obtained via the geometrical theory of diffraction. The high frequency ray solution is computed numerically by the methods of residue series, Taylor series and stationary phase in shadow, transition and illuminated region, respectively. The numerical results of the high frequency ray solution show good agreement with the eigenfunction results.     

A possibility of parallel and anti-parallel diffraction measurements on neutron diffractometer employing bent perfect crystal monochromator at the monochromatic focusing condition

In a conventional diffractometer having single monochromator, only one position, parallel position, is used for the diffraction experiment (i.e. detection) because the resolution property of the other one, anti-parallel position, is very poor. However, a bent perfect crystal (BPC) monochromator at monochromatic focusing condition can provide a quite flat and equal resolution property at both parallel and anti-parallel positions and thus one can have a chance to use both sides for the diffraction experiment. From the data of the FWHM and the Δd/d measured on three diffraction geometries (symmetric, asymmetric compression and asymmetric expansion), we can conclude that the simultaneous diffraction measurement in both parallel and anti-parallel positions can be achieved.     

Reflection of Surface Plasmon Polaritons by a Corner Reflector of Negative Index Materials

A novel type of corner reflector for the reflection of surface plasmon polariton (SPP) is proposed. The reflector consists of two layers of compensatory media whose permittivity and permeability take opposite signs to that of the corresponding layer of the SP waveguide. By rigorously solving Maxwell's equations, the reflected SPP is proved to exist. The transverse wave vector of the reflected SPP is always antiparallel to that of the incident SPP and no phase retardation is introduced.     

基于CCD采集的Mach-Zehnder干涉条纹图的处理算法

Mach-Zehnder干涉仪适用于研究气体密度迅速变化的状态。由于气体折射率的变化与其密度的变化成正比,而折射率的变化将使通过气体的光线有不同的光程,因此可通过干涉臂变化对干涉条纹图像效果的影响得到气体密度。实测中,采用图像采集卡和CCD来接收Mach-Zehnder干涉仪产生的条纹图像,再通过计算机对条纹图像的条纹间距进行处理,从而得到气体密度的变化状态。从光干涉理论出发,对Mach-Zehnder干涉条纹图像特征进行了分析,建立了Mach-Zehnder干涉条纹的数学模型,并根据此模型设计了处理Mach-Zehnder干涉条纹图像的算法。算法包括图像的预处理(即图像的噪声提取)、图像的二值化及图像的细化。     

Synthesis and characterization of highly fluorescent europium functionalized β-diketonate complexes

Several functionalized β-diketones and their europium complexes have been synthesized and characterized. The UV-Vis absorption, photoluminescent spectra, thermal and electrochemical properties of these complexes were investigated. The thermal analysis shows that the complexes have good thermal stability. By introducing the number of extended phenyl rings we succeeded in obtaining europium complexes with extremely high photoluminescent quantum yield (PLQY) in solution due to strong site isolation effect.     

等腰三角形Mindlin板的自由振动分析

提出了一种新方法来对基于 Mindlin剪切变形理论的等腰三角形板进行自由振动分析 .此方法采用了一种新的基函数并利用 pb-2 Rayleigh-Ritz边界函数得到了一种新型的 Ritz方法 .这种方法的有效性通过收敛性和对比性分析得到了证实 .数值结果表明此方法相当精确有效 .     

Mackey Theory for p-adic Lie Groups

This paper gives a p-adic analogue of the Mackey theory, which relates representations of a group of type G - H × t A to systems of imprimitivity.     

中物院远红外自由电子激光实验研究

中国工程物理研究院基于射频直线加速器技术的远红外自由电子激光(FIR-FEL)实验取得阶段性进展,于2005年3月24晚8时30分首次出光, 并多次重复. 中心波长115μm, 谱宽1%.介绍了实验系统的主要组成部分和主要实验结果.     

Tokamak中自举电流的剖面准直性

利用Harris模型,通过求解等离子体平衡方程,计算俘获粒子份额,分别对常规剪切和中心负剪切下tokamak中的自举电流的大小和剖面准直性进行了计算和分析.自举电流分布与等离子体平衡电流分布之间的剖面准直性可以通过调整等离子体的密度、温度和电流分布参数,以及描述等离子体形状的拉长度k和三角变形因子d来获得.中心负剪切位形有利于自举电流产生,并有好的剖面准直性.通过计算比较,分别在常规剪切位形下和中心负剪切位形下获得了一组优化的等离子体参数,在这组参数下,自举电流有较大的份额和好的剖面准直性 关键词： tokamak 自举电流 剖面准直性