Performance of compression/absorption hybrid refrigeration cycle with propane/mineral oil combination

This paper discusses the feasibility of a vapor compression/absorption hybrid refrigeration cycle for energy saving and utilization of waste heat. The cycle employs propane as a natural refrigerant and a refrigeration oil as an absorbent. A prototype of the cycle is constructed, in which a compressor and an absorption unit are combined in series. The performance of the cycle is examined both theoretically and experimentally. Although the solubility of the propane with the oil is not enough as a working pair in the absorption unit, the theoretical calculation shows that the hybrid cycle has a potential to achieve a higher performance in comparison with a simple vapor compression cycle by using the waste heat. In the experiment, the prototype cycle is operated successfully and it is found that an improvement of an absorber is necessary to achieve the good performance close to the theoretical one. The application of an AHE (absorber heat exchanger) can reduce the heat input to a generator. Further examinations on some other combinations of refrigerant/refrigeration oil and additives are desirable.     

GaAs半导体中三光子吸收的非线性光电导测量

采用非线性光电导技术测量2.06μm激光激发的GaAs本征半导体三光子吸收,观察到三光子和单光子吸收的混合光电导,测得了三光子吸收系数.测量结果与理论计算符合较好.     

单模光纤的传输衰减随温度变化的研究

本文从实验上测量了单模石英光纤在－50～120℃范围内的损耗。随着温度升高，光纤的损耗随之降低，在常温附近达到最小。其后损耗随着温度的继续升高而增加。损耗的变化主要是由于杂质的吸收和微弯损耗。本文对杂质的吸收以及微弯损耗进行了数值模拟，并且从理论上定性地解释了损耗对温度的依赖关系。     

Absorption of materials by or through the living skin

The skin comes into contact with a large range of materials either deliberately or inadvertently. It should be possible to predict the exact transport rates of these materials through the skin as a function of the physicochemical properties of the different compounds. With this sort of knowledge it is possible to predict the exact disposition of compounds and use this in the formulation of new products both in the pharmaceutical and cosmetic field. The information will also be useful from the standpoint of skin toxicology and environmental health. In order to be able to predict this complex process it is necessary to split the overall transport into different component parts. This article will identify these components and provide illustrations. The major areas discussed will be barrier function of the skin, the release properties of different topical formulations and how these may be monitored. Novel means of enhancing the penetration of drugs will be discussed and how some additives that are incorporated into formulations will perhaps alter the barrier function of skin. A mathematical model describing skin penetration has been developed and its use in predicting blood levels will be described. This model has been tested both in animal experiments and in limited human studies and its relevance to these situations will be highlighted.
Absorption cutanée et transcutanée in vivo     

Dissolution of Ti wires in sulphuric acid and hydrochloric acid solutions

Ti wire electrodes were immersed in acidic solutions containing H₂SO₄ and HCl of various concentrations at 353 K to evaluate corrosion rate by measurement of electric resistance change (resistometry). Addition of hydrochloric acid to sulphuric acid solution promoted depassivation of Ti. After depassivation, the immersion potential dropped to the hydrogen evolution potential and a hydride layer was formed on the surface. The hydride layer dissolved continuously in the acidic solution. SEM observation showed that Ti wires dissolved almost uniformly in the early stage and that the dissolution then trace became irregular due to nonuniform growth of the hydride layer. Dissolution rate of a Ti wire was estimated almost accurately by resistometry.     

磁偏转电子枪研制核靶

文章叙述了磁偏转电子枪的原理和结构以及用ＥＱＤ－３型电子枪研制各种核靶的工艺过程。     

GaAs／AlGaAs多量子阱红外探测器的光电流谱

测量了ＧａＡｓ／ＡｌＧａＡｓ多量子阱红外探测器在零偏压、小偏流和大偏压等条件下的光电流谱，并结合理论计算的光跃迁能量讨论了光电流谱的多峰结构和异常增强特性。     

用稳态反饱和吸收法测量C_（60）的激发态吸收截面

用准连续激光实现了Ｃ６０的稳态反饱和吸收，通过实验和理论计算的拟合，确定了Ｃ６０的三重第一激发态吸收截面。     

The combined effects of curing and environmental exposure on fracture properties of woven carbon/epoxy laminates

This paper concerns a study of the combined effects of curing conditions and environmental exposure on the ultimate properties of two commercial woven carbon/epoxy laminates. Curing parameters (heating rate and applied pressure) were varied so as to obtain six different conditions for each material. Moisture saturation was also achieved by exposing some of the cured samples to environmental conditions of 70°C and 95% relative humidity. Four different tests (tensile, impact, Mode I and Mode II interlaminar fracture resistance) were therefore performed, and the results obtained on the different materials before and after moisture saturation compared. Neither curing pressure nor heating rate nor moisture absorption were observed to have any practical effect on tensile and impact properties. On the contrary, one noticeable effect was the interlaminar fracture resistance of the laminates. The results are discussed and interpreted in terms of damage formation and stress intensification mechanisms.     

Energy absorption in splitting square metal tubes

This paper presents an investigation into the energy absorbing behaviour of axially splitting square metal tubes. Tubes 50 mm square with a variable thickness were pushed slowly against rigid pyramid shaped dies, which had various semi-angles. By pre-cutting 5 mm long slits at the four corners, the tube splits along the corners and curls outward with a certain radius at a constant force. In this energy dissipating system, there are three components: tearing energy, plastic deformation energy and frictional energy. Theoretical analysis of the three energy components is presented. Curl radius is also studied in detail. Good agreement between experiments and theory is obtained. The results show that tubes which both split and curl may be used as efficient, long stroke energy absorbing devices.