步进电机在红外系统扫描机构中的应用

介绍了在红外系统中，采用步进电机作为扫描机构驱动元件，以Ｄ／Ａ数模转换器作细分方式的定频脉宽调制驱动方式，实现微机控制下的扫描机的构步距均匀稳定，满足红外系统分辨率的要求。     

Adiabatic shear bands on the titanium side in the titanium/mild steel explosive cladding interface: Experiments, numerical simulation, and microstructure evolution

The microstructure and microtexture in adiabatic shear bands (ASBs) on the titanium side in the titanium/mild steel explosive cladding interface are investigated by means of optical microscopy, scanning electron microscopy/electron backscattered diffraction (SEM/EBSD), and transmission electron microscopy (TEM). Highly elongated subgrains and fine equiaxed grains with low dislocation density are observed in the ASBs. Microtextures (25 deg, 75 deg, 0 deg), (70 deg, 45 deg, 0 deg), and (0 deg, 15 deg, 30 deg) formed within the ASBs suggest the occurrence of the recrystallization. The grain boundaries within ASBs are geometrically necessary boundaries (GNBs) with high angles. Finite element computations are performed to obtain the effective strain and temperature distributions within the ASBs under the measured boundary conditions. The rotation dynamic recrystallization (RDR) mechanism is employed to describe the kinetics of the nanograins’ formation and the recrystallized process within ASBs. During the deformation time (about 5 to 10 μs), the following processes take place: dislocations accumulate to form elongated cell structures, cell structures break up to form subgrains, and subgrains rotate and finally form recrystallized grains. The small grains within ASBs are formed during the deformation and do not undergo significant growth by grain boundary migration after deformation.     

背景噪声限下直接检测光PPM编码系统的性能研究

本文研究了背景噪声限下采用编码的直接检测光ＰＰＭ系统的性能，分析了具有不同码率的采用硬判决译码的ＲＳ码，采用最大似然（ＭＬ）译码的卷积码的性能及未编码的ＰＰＭ系统的性能，给出了相应的误比特率和每信息比特信噪比的关系曲线。结果表明：对背景噪声限下的直接检测光ＰＰＭ系统，随着码率的降低，编码不一定能改善系统性能。     

运用韦柏函数分析发动机燃烧过程时若干问题的探讨

探讨了韦柏函数的内涵及其在实际应用中的若干问题；应用双韦柏函数对涡流室式柴油机的燃烧过程进行分析，加深了对分隔室式发动机燃烧过程的认识．     

网带式连续烧结炉炉温及网带速度微机控制系统

本文介绍一个基于ＳＴＤ总线的单片机网带式连续烧结炉炉温及网带速度控制系统，详细叙述了系统的硬件结构和控制算法。     

Band gaps and defect levels in functional oxides

Most ab-initio calculations of the electronic structure use the local density approximation, which gives good structural data but severely underestimates the band gaps of semiconductors and insulators. This paper presents calculations of the band structures and oxygen vacancy levels of some important oxide semiconductors and insulators, using density functional methods which do give more accurate band gaps. The materials SnO₂, Cu₂O, SrCu₂O₂, CuAlO₂, SrTiO₃, HfO₂, ZrO₂, La₂O₃, ZrSiO₄, and SiO₂ are covered.     

优化锰铁高炉配矿结构

介绍了通过优化高炉锰铁烧结矿原料结构，改善了烧结矿性能，使锰铁冶炼取得了增产、节焦、降成本的明显效果。     

Phase Transition VO2 Thin Films for Optical Switches

This paper presents a method to make vanadium dioxide (VO₂) crystallites on silicon substrates by reactive ion beam sputtering. The thickness of the thin film is about 100nm. The phase transition temperature of VO₂ is 65°C. The transmittance of the semiconducting phase VO₂ is about 50% and it is reduced to as low as 3% in metal phase at the infrared wavelenghth spectrum. The extinction ratio of the optical switches is 12dB. and the insertion loss is of 1-2dB. The switching time is about 1ms.