含非均匀界面相碳／碳纤维复合材料等效热传导性质的研究

本文研究含非均匀界面相碳／碳纤维复合材料的热传导性质．将非均匀界面相近似模拟为由许多性质均匀的薄层构成的层状结构，并应用Mori-Tanaka平均场概念得到了该复合材料等效热传导系数封闭形式的解析解．     

Corrosion effects of nuclear tracks in polymers

Usually ion tracks are studies ex-situ, i.e. after removal of the ion-irradiated sample from the evacuated irradiation vessel. The exposure to ambient air leads to degradation effects which are frequently neglected and consequently have been studied rarely. They have never been explained consistently. In this work we compile and discuss them in the frame of today's general understanding of ion tracks in polymers. It appears that some pristine polymers such as polyethylene are covered by a surface layer which is badly permeable for gaseous contaminants. Ion irradiation leads to destruction of this protective layer so that oxygen and moisture from the ambient air can easily penetrate through the ion tracks, and eventually even into the surrounding pristine material. Moisture absorption along the tracks gives rise to some faint conductivity. Oxygen uptake adds new trapping centers to the existing ones along the tracks, so that on one hand an increased dopant uptake capability is recorded, and on the other hand oxygen-sensitive mobile dopants are immobilized along the ion tracks. Photooxidation processes contribute to the fading of the optical blackening of irradiated polymers.     

采金船圆形跳汰机脉冲式液压系统分析

分析了采金船圆形跳汰机脉冲式液压系统的工作原理．介绍了交流液压技术及跳汰工艺．并对脉冲式液压系统中蓄能器响应性能进行了研究．     

Electrical conductivity studies of cobalt-precipitation in RbCl crystals

The results of electrical conductivity measurements in heavily doped RbCl:CoCl₂ crystals with 2500 and 6000 ppm of cobalt are being reported in this paper. The different regions of the conductivity plots for the crystals with the two concentrations of cobalt have been explained and relevant energy parameters determined. The crystals with 6000 ppm of cobalt have been found to contain two types of precipitates one of these being of the same type as that existing in RbCl crystals with 2500 ppm of cobalt while the other being of a different composition. Further, it has been found that the crystals appear blackened after heating during measurements. The blackening has been attributed to the expulsion of cobalt from the bulk of the crystal which forms an oxide at the surface.     

Structural-phase transition and electrical conductivity in tin-modified zirconium titanate

The structural phase transition in tin-modified zirconium titanate was investigated using high-temperature X-ray, DTA, DSC and electrical conductivity. In a dilute solid solution of Sn (x 0.2) in Zr_1−xSn_xTiO₄, we ascribed to the successive phase transition from normal to incommensurate the break of electrical conductivity, thermal anomalies, and specific heat anomalies occurring at temperatures of 1121 °C, 1124 °C and 1125 °C on the heating run, and at temperatures of 1121 °C, 1116 °C and 1117 °C on the cooling run, respectively. Furthermore, the super-lattice reflection intensity was inversely proportional to the Sn content, cooling rate and electrical activation energy. With a composition of Zr_0.8Sn_0.2TiO₄, the phase transition from normal to incommensurate was completely inhibited.     

Charge storage and relaxation process of polymer film by thermally stimulated discharge current technique

Charge storage and relaxation process of the polymide film electret were investigated using the thermally stimulated discharge current technique. Homo- and heterocharges were mainly observed up to and above the polarization temperature.     

高分子保护银超微粒子分散液的制备及其导电性

文题研究结果表明，高分子保护的银超微粒子分散液的导电性与反应温度、保护剂用量、还原剂种类及其用量、反应介质、银浓度、溶剂等因素密切相关，在实验范围内（银粒子直径１５～４００ｎｍ），银溶胶中银粒子平均大小不是影响导电性的关键因素。加入ＮａＯＨ以及控制反应温度，是控制银粒子平均粒径大小的有效方法。     

小型低温强制循环热水采暖系统中的安全设施

本文阐述小型低温强剖循环热水采暖系统中预防炉水汽化、循环水的热膨胀、水击以及排污、放气等安全装置的原理、结构和操作方法。     

Enhanced thermal conductance at a copper-liquid helium interface in the presence of acoustic streaming

In a conventional Kapitza resistance experiment involving heat transfer across a copper surface into liquid helium, an acoustic streaming velocity field (at 10 MHz) was directed transverse to the surface normal. Ultrasound had no observable effect on the heat transfer to the superfluid phase (He-II), but in the normal fluid phase (He-I) the thermal conductance increased linearly with acoustic velocity amplitude, reaching a value 2.5 times the zero sound conductance for a sound velocity amplitude of 0.8 cm s^?1.