低频液体表面波激光衍射条纹的特征

用激光衍射法实现了低频液体表面波稳定、清晰、反衬度非常高的条纹,并发现了缺级现象.理论上分析了表面波的光衍射效应,得到了衍射光场和表面波之间的解析表达式,表达式包括衍射因子和干涉因子.通过对衍射因子和干涉因子的分析,得到衍射条纹空间分布与表面波波长的关系、条纹的半角宽度与入射激光光斑覆盖表面波的个数和入射方向的关系、衍射光强度与表面波振幅的关系,并解释了条纹缺级现象.     

激光激发源对声表面波的影响

利用激光激发声表面波及光差分技术研究激光源对声表面波的影响。实验中利用了Nd∶YAG脉冲激光器激发超声,采用632nm的He-Ne激光器基于光束偏转法的光差分检测系统,测量了铝样品表面的声表面波,获得了很好的信号。在此基础上研究了激发源的形状和能量对激发的声表面波幅度的影响。同时从热弹和融蚀机制下讨论激光声表面波的产生。在这两种机制下,声表面波的幅度发生了很大的变化。随着激光能量密度的增加,声表面波的幅度由线性变化转换为非线性变化。这一结果对激光激发声表面波理论研究有一定的指导意义。     

光生毫米波技术

在概述光生毫米波基本原理的基础上,介绍了产生毫米波的强度调制技术、光注入锁定技术、光外差技术及光电振荡器等四种方案的基本原理。通过对几种典型实验装置的分析,比较了这四种实验方案的优缺点及其发展方向。     

半导体激光并超短波治疗慢性前列腺炎的临床观察

目的：观察半导体激光治慢性前列腺炎的临床疗效。方法：将患者140例随机分为2组．治疗组76例,采用半导体激光并体外短波对会阴部治疗;对照组64例,单纯采用体外短波治疗。结果：治疗组有效率为89．2％;对照组有效率为76．5％。两组比较差异显著（P＜0．05）。结论：半导体激光照射治疗慢性前列腺炎可明豆糖高疗效。     

快速扫描毫米波单脉冲天线设计

采用极化扭转式卡氏天线、四喇叭馈源和波导混合环式和差网络实现了8mm波快速扫描单脉冲天线。给出了天线各部分的设计、公差分析和仿真。由于设计时进行了详细的公差分析,样机几乎未经任何调试,便全面满足设计要求,主要指标与仿真结果非常吻合,表明给出的设计方法和公差分析对工程设计有较强的指导意义。     

逆合成孔径雷达(ISAR)成像

逆合成孔径雷达（ISAR）重点论述用固定雷达对活动目标成像,例如对飞机成像或对船成像等。由于飞机比船只小得多,因此成像也较难,为此,着重综述对飞机的成像。选取了各有代表性模型飞机、真实飞机中的直升机和民航机、还对两架圆周飞行的飞机进行了瞬时双机成像。     

Jordan–Cattaneo waves: Analogues of compressible flow

We review work of Jordan on a hyperbolic variant of the Fisher–KPP equation, where a shock solution is found and the amplitude is calculated exactly. The Jordan procedure is extended to a hyperbolic variant of the Chafee–Infante equation. Extension of Jordan’s ideas to a model for traffic flow are also mentioned. We also examine a diffusive susceptible–infected (SI) model, and generalizations of diffusive Lotka–Volterra equations, including a Lotka–Volterra–Bass competition model with diffusion. For all cases we show how a Jordan–Cattaneo wave may be analysed and we indicate how to find the wavespeeds and the amplitudes. Finally we present details of a fully nonlinear analysis of acceleration waves in a Cattaneo–Christov poroacoustic model.     

Alfvén waves in temperature anisotropic Cairns distributed plasma

The dispersion relations and Landau damping of Alfven waves in kinetic and inertial limits are studied in temperature anisotropic Cairns distributed plasma.In the case of kinetic Alfven waves(KAWs),it is found that the real frequency is enhanced when either the electron perpendicular temperature or the non-thermal parameter A increases.For inertial Alfven waves(IAWs),the real frequency is slightly affected by the electron temperature anisotropy and A.Besides the real frequency,the damping rate of KAWs is reduced when the electron perpendicular temperature or A increases.In the case of IAWs,the temperature anisotropy and A either enhance or reduce the damping rate depending upon the perpendicular wavelength.These results may be helpful to understand the dynamics of KAWs and IAWs in space plasmas where the non-Maxwellian distribution of particles are routinely observed.     

Structure formation in turbulence as an instability of effective quantum plasma

Structure formation in turbulence can be understood as an instability of “plasma” formed by fluctuations serving as effective particles. These “particles” are quantumlike in the sense that their wavelengths are non-negligible compared to the sizes of background coherent structures. The corresponding “kinetic equation” describes the Wigner matrix of the turbulent field, and the coherent structures serve as collective fields. This formalism is usually applied to manifestly quantumlike or scalar waves. Here, we show how to systematically extend it to more complex systems using compressible Navier–Stokes turbulence as an example. In this case, the fluctuation Hamiltonian is a five-dimensional matrix operator and diverse modulational modes are present. As an illustration, we calculate these modes for a sinusoidal shear flow and find two modulational instabilities. One of them is specific to supersonic flows, and the other one is a Kelvin–Helmholtz-type instability that is a generalization of the known zonostrophic instability. Our calculations are readily extendable to other types of turbulence, for example, magnetohydrodynamic turbulence in plasma.     

Electrodynamics of Magnetoelectric Media and Magnetoelectric Fields

The relationship between magnetoelectricity and electromagnetism is a subject of a strong interest and numerous discussions in microwave and optical wave physics and material sciences. The definition of the energy and momentum of the electromagnetic (EM) field in a magnetoelectric (ME) medium is not a trivial problem. The question of whether electromagnetism and magnetoelectricity can coexist without an extension of Maxwell's theory arises when the effects of EM energy propagation are studied and the group velocity of the waves in an ME medium is considered. The energy balance equation reveals unusual topological structure of fields in ME materials. Together with certain constraints on the constitutive parameters of a medium, definite constraints on the local field structure should be imposed. Analyzing the EM phenomena inside an ME material, the question “what kind of the near fields arising from a sample of such a material can be measured?” should be answered. The visualization of the ME states requires an experimental technique that is based on an effective coupling to the violation of spatial as well as temporal inversion symmetry. To observe the ME energy in a subwavelength region, it is necessary to assume the existence of first-principle near fields—the ME fields. These are non-Maxwellian near fields with specific properties of violation of spatial and temporal inversion symmetry. A particular interest to the ME fields arises in studies of metamaterials with “artificial-atoms” ME elements.