线性主动结构及模态（I）——基本概念及属性

阐明了主动结构的若干基本概念，归纳了主动结构动力学的主要问题．对线性主动结构的模态做了注释，注释包括：右和左特征向量的物理意义，右特征向量为振型，左特征向量表征响应的模态分量；伴随结构及互易定理，两个互为伴随主动结构，且有对偶反馈增益矩阵，左和右特征向量互易；主动结构与被动结构的关联用传递函数表示，可用于主动结构的估计问题．     

Vibration-induced change of crystal structure in isotactic polypropylene and its improved mechanical properties

In order to understand the formation of different crystal structures and improve the mechanical properties of isotactic polypropylene (iPP), melt vibration technology, which generally includes shear vibration and hydrostatic pressure vibration, was used to induce the change of crystal structure of iPP. iPP forms α crystal structure in traditional injection molding. Through melt vibration, crystal orientated and its size became smaller, and a change of crystal structure of iPP from α form to β form and γ form was achieved. Therefore, the mechanical properties of iPP were improved. At high melting temperature (230 °C), only β form can be induced. At low melting temperature (190 °C), either β form or γ form can be induced, depending on the combination of frequency and vibration pressure. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2385–2390, 2004     

第一性原理研究一维SiO2纳米材料的结构和性质

运用密度泛函理论，在6-31G(d)基组水平上，对二元环组成的SiO₂单链、双链纳米线和三元环组成的纳米管进行几何优化，并对其结合能、电子结构和振动频率进行计算.结果表明，平均结合能和能隙均随着SiO₂单元的增加单调变化.红外光谱的分析发现，径向和切向的振动频率与强度随着长度的变化有明显的移动.径向的振动频率向高频端移动，而切向的振动频率则向低频端移动，即SiO₂纳米材料中存在量子尺寸效应和各向异性现象. 关键词： 2纳米材料')" href="#">SiO₂纳米材料 能隙 振动光谱 尺寸效应     

Detection of the frustrated rotation mode of CO on Cu(0 0 1) by very low energy photoelectron spectroscopy

We have measured the very low energy photoelectron spectra of the clean and CO covered Cu(0 0 1) surfaces at low temperature (15 K). A step at 34.5 meV below the Fermi level appeared in the CO/Cu(0 0 1) spectra, while no structure was found at the same position in the clean Cu(0 0 1) spectrum. Furthermore, we have succeeded in measuring the spectral shift of the step to 33.2 meV below the Fermi level by isotopic substitution of the CO molecule. We have concluded that this step originates from the inelastic scattering of photoelectrons through excitation of the frustrated rotation mode of the CO molecule.     

Unsteady characteristics of the cavity flow around a rough circular cylinder

Effects of surface roughness on the unsteady cavitating flow around a two-dimensional circular cylinder were experimentally investigated at Reynolds numbers from 1.36 × 10⁵ to 1.78 × 10⁵. Two patterns of surface roughness were investigated, a double-cut pattern and a single-cut pattern. The cavity elongates with an increase of the surface roughness, especially in supercavitating flow. However, for some roughness parameters tested, the cavity length exhibits an extreme decrease. In a particular case of the double-cut pattern, there exists the minimum cavity behind the cylinder.     

双参数地基上圆（环）板轴对称稳态振动的解析解

本文应用贝塞尔函数理论，根据不同的ω值获得了双参数地基上圆（环）板轴对称稳态振动的解析解。最后，给出了一些计算结果。     

[FC(O)]_2S_2和[ClC(O)]_2S_2分子的结构及动力学性质

用从头计算方法计算了FC(O)SSC(O)F和ClC(0)SSC(O)Cl分子的结构、势能分布及振动谱。结果表明:FC(O)SSC(O)F具有两种稳定构型(Ⅰ和Ⅱ)。在气相中构型Ⅰ最稳定,具有C_2点群对称性,构型Ⅱ属于C_1点群;ClC(O)SSC(O)Cl仅仅具有一种稳定构型,属于C_2点群。利用势能分布及同位素替代方法确定了振动归属,计算得到的振动频率结果和实验很好地一致。     

轨道振动的非接触测量

ＣＣＤ实时地非接触检测铁轨的振动情况是一种既方便又准确的测量方法。该方法能够测出轨道振动的幅度、频率、相位、加速度等参数。ＣＣＤ非接触测振系统由照明光源、成像系统、ＣＣＤ、检测逻辑接口电路及计算机软件构成。通过实际检测，它能够达到振幅测量精度为０．１ｍｍ，最大量程为１００ｍｍ，频率不低于２００Ｈｚ。该系统可扩展到用非接触方法测量各种机械振动、位移量和物体边沿检测等应用领域。     

BS分子α带系A~2Π→X~2Σ~+及γ带系C~2Π→X~2Σ~+法兰克-康登因子的计算

在双原子分子核运动的薛定谔方程中，计入分子的振转相互作用项，在Ｍｏｒｓｅ势近似下得出的波函数除与振动量子数有关外，还与转动量子数有关。本文用该波函数编程计算了ＢＳ分子α带系Ａ２Π→Ｘ２Σ＋及γ带系Ｃ２Π→Ｘ２Σ＋法兰克－康登（Ｆｒａｎｃｋ－Ｃｏｎｄｏｎ）因子（简称Ｆ－Ｃ因子）。计算中转动量子数的取值由Ｊ＝０至Ｊ＝２００，其结果适用于低温、高温和强激波条件。