LURR's Twenty Years and Its Perspective

Seismogenic process is a nonlinear and irreversible one, so that the response to loading of a seismogenic zone is different from the unloading one. This difference reflects quantitatively the process of an earthquake preparation. A physics-based new parameter-Load/Unload Response Ratio (LURR) was proposed to measure quantitatively the proximity to a strong earthquake and then used to be an earthquake predictor. In the present paper, a brief history of LURR is recalled; inspection of real earthquake cases, numerical simulations and laboratory studies of LURR, prediction efforts in terms of LURR, probability problem of LURR and its prospect are also expatiated.

Principles of flow field diagnostics by laser-induced biacetyl phosphorescence

A new method for measuring the density, temperature and velocity of N2 gas flow by laser induced biacetyl phosphorescence is proposed. The characteristics of the laser induced phosphorescence of biacetyl mixed with N2 are investigated both in static gas and in one-dimensional flow along a pipe with constant cross section. The theoretical and experimental investigations show that the temperature and density of N2 gas flow could be measured by observing the phosphorescence lifetime and initial intensity of biacetyl triplet (3Au) respectively. The velocity could be measured by observing the time-of-flight of the phosphorescent gas after pulsed laser excitation. The prospect of this method is also discussed.

Visualization of turbulence and internal waves in a stratified fluid

A new method for measuring the density, temperature and velocity of N2 gas flow by laser induced biacetyl phosphorescence is proposed. The characteristics of the laser induced phosphorescence of biacetyl mixed with N2 are investigated both in static gas and in one-dimensional flow along a pipe with constant cross section. The theoretical and experimental investigations show that the temperature and density of N2 gas flow could be measured by observing the phosphorescence lifetime and initial intensity of biacetyl triplet (3Au) respectively. The velocity could be measured by observing the time-of-flight of the phosphorescent gas after pulsed laser excitation. The prospect of this method is also discussed.

超高周疲劳研究现状及展望

超高周疲劳是指疲劳周次达到108及其以上时材料的疲劳行为.与一般认识的疲劳行为不同之处是,超高周疲劳发生在传统疲劳极限以下,因此研究超高周疲劳行为有助于进一步理解疲劳的本质和疲劳机理.文中综述近几年超高周疲劳研究的进展,包括超高周疲劳的典型特征,如S-N曲线的特点、断口特征、断面上的鱼眼形貌以及裂纹的起源与扩展特征等;分析疲劳机理和相关的模型以及简要探讨影响超高周疲劳的一些因素,如加载频率、加载方式、氢的作用等.在此基础上提出值得进一步研究的几个问题.

On a novel method of impact by a front-end-coated bullet to evaluate the interface adhesion between film and substrate

A preliminary experiment was carried out to validate the feasibility of the method of impact by a front-end-coated bullet to evaluate the interface adhesion between film and substrate. The theoretical description of the initiation, propagation and evolution of the stress pulse during impact was generalized and formulized. The effects of the crucial parameters on the interface stress were further investigated with FEM. The results found the promising prospect of the application of such a method and provided useful guidance for experimental design.

利用受激发射损耗（STED）显微术突破远场衍射极限

远场光学显微镜受衍射极限分辩率的限制，而近场光学显微镜由于缺乏层析能力，则无法实现超分辨的三维成像，研究了既可突破远场光学显微术的衍射极限分辨率又可实现三维成像的成像技术——受激发射损耗（STED），综述了STED的分辨率与STED光的光强，延迟时间、光斑空间分布等主要参数的关系，以及该技术的最新进展和应用前景。

消色差相位匹配在光参量啁啾脉冲放大中的应用

Optical parametric chirped-pulse amplification (OPCPA) supplies broadband gain for ultrashort pulses. A new theoretic explanation of OPCPA has been obtained by introducing the concept of tilted pulse front in this paper, and the distribution of broadband amplification has been twice expanded by introducing the technology of achromatic phase matching (APM). The prospect of APM in OPCPA has been discussed in detail. Finally, a design for the amplification of chirped pulses at 1600 nm has been firstly proposed and numerically simulated. (C) 2004 Elsevier B.V. All rights reserved.

High-energy ion emission from cooled deuterium clusters in 20 TW laser fields

High-energy ion emission from intense-ultrashort (30fs) laser-pulse- cooled deuterium-cluster (80K) interaction is measured. The deuterium ions have an average energy 20keV, which greatly exceeds Zweiback's expectation [Phys. Rev. Lett. 84 (2000) 2634]. These fast deuterium ions can be used to drive fusion and have a broad prospect.

自由空间相干光通信技术及发展

对比了相干探测和直接探测，以及自由空间相干光通信和光纤相干通信，对相干自由空间激光通信系统的特点和关键技术进行了讨论，回顾了近年来国外在自由空间相干光通信领域内开展的有关研究计划。最后对相干光通信技术的应用前景进行了展望。

光折变相干散射噪声

全面介绍了光折变相干散射噪声的研究状况，描述并分析了形成散射噪声的必要条件及理论机制，说明了散射噪声的观测技术及评价标准；总结了抑制噪声的各种方案及噪声的相关应用，最后展望了光折变散射噪声的研究前景。

氧化物记录介质在光存储中的应用及其研究进展

系统总结了用于光存储记录层的氧化物薄膜的存储机理、存储特性以及最新进展，讨论了氧化物掺杂对提高存储性能的影响，指出了氧化物薄膜存在的不足，并探讨了可能的改善途径。在此基础上对存储材料的发展趋势及氧化物材料的研究前景进行了展望。