大型复杂高精度波导钎焊设备的研制：简介ZHS—132型真空钎焊炉

应军事电子装备，特别是军用雷达预研和生产的急需，电子工业部第二研究所近期研制的成功大型、复杂、高精度波导钎焊设备ＺＨＳ－１３２型真空钎焊炉。文中主要介绍了该设备的开发背景和对波导钎焊工艺的影响，该设备的设计构思、结构和技术特征，使用功能和效果，以及推广应用前景。     

沈阳太平洋广场空调冷热源方案比较

对一幢１１．５万ｍ＾２的四星级综合建筑的空调冷热源不同的蓄冷和取冷比较了四种方案，论证了其中直燃型溴化锂吸收式冷热水机组供冷供暖、小型燃油锅炉供蒸汽的方案最为合理。     

挟沙水流中沙粒对底壁湍流猝发的影响

本文在常规的边界层方程中保留了法向压力梯度项和增加了固粒对流体的使用项，结合Ｂａｔｃｈｅｏｌｒ对交界面提供的分析方法和小扰动稳定性理论，由理论分析和计算得到了包括沙粒之类的悬浮体的尺寸，比重，流动Ｒｅ数，两相速度差以及扰动波数与水流底壁湍流猝发角的关系，计算结果与Ｒａｓｈｉｄｉ等的实验结果相符。文中所得结果有助于进一步了解江河底部水流的流动特性以及泥沙的沉积和输运机理。     

Degradation of NiCr/CuNiMn/NiCr films on alumina substrates

This paper addresses the aging behaviour of NiCr/CuNiMn/NiCr triple layers on Al₂O₃ ceramics at temperatures up to 200°C for film thicknesses d0.5 μm. Investigations of the film structure and the increase of resistance and its temperature coefficient during the annealing process and studies of the dependence of this aging drift on both the film thickness and the storage temperature have been carried out. Furthermore, the film stress and the effect of substrate bending on resistance have been measured. The results can be explained by the irregular film structure (columns and small bridges between them), which causes stress and current concentrations as well as local creeping, cracking and oxidation processes in the micro-bridges. They are compared with such for structurally homogeneous films on silicon wafers.     

非均匀介质中的场与波：理论及其在电测井中的应用

本文综述了非均匀介质中场与波理论近年来的研究进展及其应用成果，着重介绍了非均匀介质中的电磁场正演分析和反演计算中的各种高效数值方法，以及它们在电法测井数值模拟和成象研究中的成功应用。     

无源微波遥感用于地震预报的实验研究

对无源微波遥感用于地震预报在理论研究的基础上对不同岩性不同结构的岩石试件进行了加载实验，测量了岩石试件的微波辐射随载荷的变化．实验得出：岩石试件的微波辐射能量随岩石应力状态变化而显著变化；而且，不同的波段变化的幅度不同；同一波段不同极化方式的波随应力变化的变化量也不同；微波辐射能量的变化能够被卫星微波遥感探测器探测到．实验还发现，岩石试件临破裂前出现明显的微波辐射异常．     

多层多跨铰接框架计算

本文采用柔度矩阵法,对多层多跨铰接框架进行静力与动力分析,附有实例。与刚度法相比,其优点是使矩阵降价,方法实用,可应用于工业厂房和一般刚架设计中。     

SURFACE TENSION AND BUOYANCY DRIVEN INSTABILITIES IN A LAYER OF LIQUID TIN HEATED FROM BELOW

The linear theory of Pearson (1958) and Nield (1964) is modified here to study liquid tin and include the finite thermal resistances of the bounding layers of boron nitride, copper and air (∼10^-2 torr) in the experiments of Ginde et al. (1989). The magnitude of the ΔT_c across the layer of liquid tin required for the onset of convection depends on the ratios of the thermal conductivities and thicknesses of the supporting layers of boron nitride and copper to those of the tin.

According to our theory surface tension contributes more than buoyancy to the instability observed experimentally. The critical ΔT_c observed required for the onset of convection in the layer of tin, is up to 25% lower than that predicted, which shows the layer is less stable than the theory indicates. Thus the surface of the tin was uncontaminated, or a significantly larger observed critical ΔT_c would be expected.

The boundary condition on the thermal fluctuations at the base of the supporting layer of copper does not appear to be important in these experiments. However, the thermal resistance of the boron nitride would have to be assumed to be unrealistically large to obtain agreement within experimental error with the theory.