“嫦娥一号”上的科学探测仪器

“嫦娥一号”上搭载了8种24台件科学探测仪器，重130kg，即微波探测仪系统、γ射线谱仪、X射线谱仪、激光高度计、太阳高能粒子探测器、太阳风离子探测器、CCD立体相机、干涉成像光谱仪．     

气泡的远场干涉分析及应用

提出了一种分析气泡远场干涉的理论模型。平行激光束照射到透明介质中的气泡上,折射光束与全反射光束在远场发生干涉形成内密外疏圆环状干涉条纹,推求了两平行出射光线的光程差公式和两光线之间的距离公式,分析了圆环状干涉条纹内密外疏的原因,给出了计算干涉条纹存在区域和最高干涉级的方法。通过干涉方法可以测量气泡的直径,能够用于介质深处气泡尺寸的测量。利用远场干涉对玻璃水箱、平板玻璃、玻璃棱镜中的气泡直径进行了测量,其中玻璃棱镜中气泡直径测量结果与用阿贝比长仪测量结果对比,相对差为0.9%。预期了气泡远场干涉在运动气泡尺寸、泡内气体折射率、透明光疏介质中光密介质球尺寸测量等方面的应用。     

轴向间隙对压气机时序效应影响之二：截面特性

本文实验研究不同轴向间隙、不同静叶时序角度对某低速轴流压气机出口流场的影响.结果表明,当一级静叶尾迹位于二级静叶流道中央位置时对应压气机最低效率状态;一级静叶尾迹重合或接近于二级静叶尾迹时对应压气机最高效率状态.随着轴向间隙的减小,压气机的扩压能力逐渐增强,通流能力下降.此外,设计工况下压气机输入功率也随轴向间隙的减小而增大.综合考虑轴向间隙对压气机扩压能力、通流能力及输入功率的影响,推测存在一个最佳轴向间隙,使得各项因素达到最优匹配,实现压气机的最佳性能.     

Optimal Acoustic Attenuation of Weakly Compressible Media Permeated with Air Bubbles

Based on fuzzy logic （FL） and genetic algorithm （GA）, we present an optimization method to obtain the optimal acoustic attenuation of a longitudinal acoustic wave propagating in a weakly compressible medium permeated with air bubbles. In the optimization, the parameters of the size distribution of bubbles in the medium are optimized for providing uniformly high acoustic attenuation in the frequency band of interest. Compared with other traditional optimization methods, the unique advantage of the present method is that it can locate the global optimum quickly and effectively in need of knowing the mathematical model precisely. As illustrated by a numerical simulation, the method is effective and essential in enhancing the acoustic attenuation of such a medium in an optimal manner. The bubbly medium with optimized structural parameters can effectively attenuate longitudinal waves at intermediate frequencies with an acoustic attenuation approximating a constant value of lO（dB/cm）. Such bubbly media with optimal acoustic attenuations may be applied to design acoustic absorbent by controlling broader attenuation band and higher efficiency.     

Evolution of Matter Wave Interference of Bose-Condensed Gas in a 1D Optical Lattice

For a Bose-condensed gas in a combined potential consisting of an axially-symmetric harmonic magnetic trap and one-dimensional （1D） optical lattice, using the mean-field Gross-Pitaevskii （G-P） equation and the propagator method, we obtain the analytical result of the order parameter for matter wave interference at any time. The evolution of the interference pattern under a variation of the relative phase △Ф between successive subcondensates trapped on an optical lattices is also studied. For △Ф=π, the interference pattern is symmetric with two sharp peaks, which are symmetrically located on a straight line on both sides of a vacant central peak and moving apart from each other. This work is in agreement with available experimental results.     

The interference characteristics of platform and towed body noise in shallow water for active/passive towed array sonar

The interference characteristics of towed platform noise resulted from propeller and towed body for active/passive towed array is analyzed. It is shown that, in shallow water environment, the direct wave and bottom/sea surface reflected wave will seriously affect the performance of sonar system. The formula for calculating the direction of arrival (DOA) of interference in terms of various parameters, such as array depth, length of tow cable, is derived. The effect of interference noise for the detection performance of sonar system is described. The results of system simulation provide the method for reducing the effect of these kind of interferences.     

Fast scheme for generating quantum-interference states and GHZ state of N trapped ions

We propose a fast scheme to generate the quantum-interference states of N trapped ions. In the scheme the ions are driven by a standing-wave laser beam whose carrier frequency is tuned such that the ion transition can take place. We also propose a simple and fast scheme to produce the GHZ state of N hot trapped ions and this scheme is insensitive to the heating of vibrational motion, which is important from the viewpoint of decoherence.     

量子理论与医学技术的发展

综述光量子血疗仪、核磁共振成像仪和量子共振检测仪的基本原理、应用与发展．     

The solution of a wedge disclination dipole interacting with an annular inclusion and the force acting on the disclination dipole

The interaction between a wedge disclination dipole and an elastic annular inclusion is investigated. Utilizing the Muskhelishvili complex variable method, the explicit series form solutions of the complex potentials in the matrix and the inclusion region are derived. The image force acting on the disclination dipole centre is also calculated. The influence of the location of the disclination dipole and the thickness of the annular inclusion as well as the elastic dissimilarity of materials upon the equilibrium position of the disclination dipole is discussed in detail. The results show that a stable equilibrium point of the disclination dipole near the inclusion is found for certain combinations of material constant. Moreover, the force on the disclination dipole is strongly affected by the position of the disclination dipole and the thickness of annular inclusion. The repulsion force increases （or the attraction force reduces） with the increase of the thickness of the annular inclusion. An appropriate critical value of the thickness of the annular inclusion may be found to change the direction of the force on the disclination dipole. The present solutions include previous results as special eases.     

基于光反馈自混合干涉效应波形转折点的智能识别

对光反馈自混合干涉信号波形转折点的智能识别进行了理论分析和实验研究。首先经对光反馈自混合干涉信号特点的分析，发现其波形转折点可以作为外部物体运动位移实时测量的依据。通过对信号波形的逐步处理可以获得波形转折点的位置，以此为基准点可以实现位移的精测。实验测试结果同理论分析吻合较好。若系统进入较复杂状态，识别出的位置与其实际位置出现偏差，不再是单一值，可以对转折点位置的所有值取平均，从而得到其对应的精确位置。