钒氧酞菁多晶薄膜的稳态光电压特性研究

报道了Ａｌ／ＶＯＰｃ／ＩＴＯ夹心结构在稳态连续光照射下的光电压作用谱，稳态光电压作用谱不仅依赖于照射光的波长，而且依赖于ＶＯＰｃ（钒氧酞菁）多晶薄膜的堆积方式，对ＶＯＰｃ在相１，相１１，及α型三种堆积方式的稳态电压波长响应进行了研究，并对其内在机制作了初步探讨。     

法布里－珀罗标准具滤波器对超短光脉冲的时间响应

系统地研究了法布里－珀罗标准具滤波器对超短光脉冲的时间响应。由于光在标准具内多次反射所引起的干涉效应，发现输出的光脉冲包含了一连串的次脉冲，这些次脉冲的时间间隔等于光单次通过标准具的时间。在一定条件下，这些次脉冲简并在一起产生一展宽的输出光脉冲，并且输出和输入光脉冲峰值的时间间隔并不等于光单次通过标准具的时间。并得出了在考虑色散和啁啾情况下输出次脉冲的表达式。     

On van Kampen's objections against linear response theory

A discussion is given of the derivation of the Kubo-Green formulas. A reformulation of the derivation is presented, which leads to an exact result, involving field-dependent transport coefficients. Kubo's result is obtained as the first-order term in a resolvent expansion. For the general Liouville operator case, in accord with van Kampen's objections, it cannot be argued that the other terms are negligible. However, for a large class of systems, this can be justified. This is shown for systems where dissipation is due to weak interactions, amenable to the Van Hove limit, and having sufficiently short relaxation times.     

Using optimized surface modifications to improve low frequency response in a room

A case study of improving sound energy distribution at low frequency in a small orthogonal room is presented in this paper. The effects of the geometric modifications of wall surface on the sound frequency response have been investigated in depth. In order to find the optimal modifications for the wall surface, an optimization procedure, based on finite element analysis, has been developed. The uniqueness of this method is that it takes both modal redistribution and sound diffusion into account during optimization process. As a result, the promising improvements of sound frequency response have been obtained at the frequencies around 100 Hz in all rooms tested, particularly in those where the serious modal concentrations are met. The maximum reduction of sound fluctuation in such a room could reach a mount of 4.6 dB. The work opens up the possibility of improving low frequency sound quality by a means that considers both modal changing and surface scattering at same time.     

Dynamic response of high-resolution ring resonator optical spectrometers to time-varying input signals

An analysis and experimental data of the time-dependent response of an all-fiber ring resonator in which the ring is illuminated by a phase modulated input beam are presented. The resonator is operated as a high-resolution optical-scanning spectrometer. Since the resolution limit is a function of the finesse and cavity-loop length, we will show that it is not possible to design a high-resolution ring resonator that will not produce a distorted output signal when the phase modulation rate is comparable to the response time of the ring.     

Gas sensor response time analysis for tapered porous-clad fibers

The detection of gases with the use of ATR spectroscopy in a multimode step-index-tapered fiber with porous cladding has been described. Geometrical optics has been used to derive an expression for the time-dependent evanescent absorbance as the gas diffuses through the cladding. The ratio of the radii of core and cladding has been assumed to be constant throughout the length of the taper. It has been shown that the relative evanescent absorbance depends on the taper ratio. As the taper ratio increases, the response time of the sensor decreases.     

Spatial Frequency Response and Transient Anisotropy in Bacteriorhodopsin Thin Films

In this paper, we present new results describing the spatial frequency response in bacteriorhodopsin (bR), immobilised in gelatin films. It is shown that the spatial frequency response is flat, as compared to bR contained in solution form. An experimental investigation into the photoinduced anisotropy of bR films is also presented. It is shown that the anisotropy can be induced using two wavelengths (632.8 nm and 454 nm) and is dependent on the pH of the gelatin matrix, the 454 nm laser polarisation and the 454 nm pump power. The mechanisms producing the anisotropy are briefly discussed.Presented at the International Commission of Optics Topical Meeting, Kyoto, 1994.     

非晶硒化镉和辉光放电非晶硅对锁模激光的瞬态响应

用对撞锁模Nd:YAG激光器产生的超短光脉冲对非晶硒化镉和辉光放电非晶硅的瞬态响应进行研究,并用多重俘获传导模型分析光生载流子的弛豫过程.     

Dynamic analysis of baffled fuel‐storage tanks using the ALE finite element method

This paper is concerned with the parametric investigation on the structural dynamic response of moving fuel‐storage tanks with baffles. Since the structural dynamic behaviour is strongly coupled with interior liquid motion, the design of a fuel‐storage tank securing the structural stability becomes the appropriate suppression of the flow motion, which is in turn related to the baffle design. In order to numerically investigate the parametric dynamic characteristics of moving tanks, we employ the arbitrary Lagrangian–Eulerian (ALE) finite element method that is widely being used to deal with the problems with free surface, moving boundary, large deformation and interface contact. Following the theoretical and numerical formulations of fluid‐structure interaction problems, we present parametric numerical results of a cylindrical fuel‐storage tank moving with uniform vertical acceleration, with respect to the baffle number and location, and the inner‐hole diameter. Copyright © 2003 John Wiley & Sons, Ltd.     

静力分析的一般随机摄动法

本文对向量值和矩阵值函数的不确定结构的静力响应和可靠性进行了研究。基于Ｋｒｏｎｅｃｋｅｒ代数和摄动理论导出了随机结构的有限元分析方法，随机变量和系统导数很方便地排列到２Ｄ矩阵中，给出了一般的数学表达式．