A new bubble-point-pressure correlation for the binary LiBr/H2O solution

In accord with the increasing concern about the global environmental issues, the absorption refrigeration heat-pump systems are currently being considered very promising and attractive. For the purpose of supporting the advanced R&D technology in this area, we have developed a novel correlation to represent the bubble-point pressures of LiBr H₂O solutions. The developed correlation covers the most extensive range of validity ever proposed: 273–483 K for temperatures, 0.05 kPa to 1.0 MPa for pressures. and 29 76 wt% LiBr for concentrations.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994. Boulder, Colorado, U.S.A.     

Substituted uracils as corrosion inhibitors for copper in 3% NaCl solution

Substituted uracils were tested as corrosion inhibitors of copper in 3% NaCl medium using electrochemical polarisation, impedance measurements and non-electrochemical techniques (weight loss, IR and UV-visible). This study permitted to follow the evolution of the inhibitory effect of the uracil derivatives, according to their substituents, on copper in 3% NaCl medium. Comparison of results showed that dithiouracil (DTUr) was the best inhibitor. The maximum inhibition efficiency reached 98% at 10⁻³ M. DTUr adsorbs on the copper surface according to the Frumkin isotherm model.     

具有偏差变元的Volterra型系统的周期正解

利用Mawhin重合度理论研究了一类具有偏差变元的Volterra型系统周期正解的存在性问题，得到了一个新的存在性定理。     

深亚微米集成电路的快速时域仿真技术

随着深亚微米集成电路技术的发展，集成电路的规模越来越大，工作频率越来越高，并正朝着系统集成的方向发展，因而在模拟速度，模拟精度和可模拟的电路规模等各个方面对电路仿真技术提出了新的要求。近年来，各种新的电路仿真方法和仿真系统用相继脱颖百出，并将取代那些传统的，已经无法适应深亚微米技术发展的电路仿真器。     

THE FLOW PRODUCED IN PARTICLE-SUSPENSION BY AN INFINITE ROTATING DISK:SERIES SOLUTION

To the flow produced in particle-suspension by a rotating disk of infinite extent,the asymptotic behavior at infinity is analyzed.A corresponding series solution is presented.It isshown that this approach yields widely valid solutions of high accuracy for all the cases in whichthat suction or weak injection at the disk surface exists.For the cases that strong injection or par-ticle-free band exists,the series method fails.     

Integrating neural network technology and noise analysis

The integrated use of neural network and noise analysis technologies offers advantages not available by the use of either technology alone. The application of neural network technology to noise analysis offers an opportunity to expand the scope of problems where noise analysis is useful and unique ways in which the integration of these technologies can be used productively. The two-sensor technique, in which the responses of two sensors to an unknown driving source are related, is used to demonstration such integration. The relationship between power spectral densities (PSDs) of accelerometer signals is derived theoretically using noise analysis to demonstrate its uniqueness. This relationship is modeled from experimental data using a neural network when the system is working properly, and the actual PSD of one sensor is compared with the PSD of that sensor predicted by the neural network using the PSD of the other sensor as an input. A significant deviation between the actual and predicted PSDs indicate that system is changing (i.e., failing). Experiments carried out on check valves and bearings illustrate the usefulness of the methodology developed.     

聚电解质溶液分子热力学模型

<正>链状聚电解质由于是长链大分子又有很高的电荷密度,其溶液即使在极低的浓度下仍具有很强的负偏差,与Debye-Huckel理论预测的结果相去甚远。工程上使用的Manning模型认为聚离子的电荷密度有一临界值,当超过临界值时,反离子即凝聚在聚离子表面使其实际电荷密度降至临界值。Nagvekar等在该模型的基础上引入NRTL方程,以计及短程相互作用的贡献。Manning等的方法虽然有一定的物理意义,但临界值的确定缺乏可靠的根据。     

多人决策的一类相对均衡解

本文分析由于决策人偏好不同而引起决策差异的多人多目标决策问题，提出了这类决策问题的一类相对均衡解的概念和求取方法。相对均衡解以决策群体偏好的加权集结为基础，能最大程度地反映每个决策人的偏好。文中研究相对均衡解的ＳＷＴ求取方法，并给出了求解的步骤。     

Fundamental solutions for half plane with an oblique edge crack

An elastic half plane with an oblique edge crack is considered in this paper. A pair of concentrated forces or point dislocations is assumed to act at an arbitrary point in the half plane. The half plane with an edge crack is first mapped into a unit circle by a rational mapping function so that the following analysis can be carried out on the mapped plane analytically. Then the complex stress functions are derived by separating the whole problem into two parts; one is the principal part corresponding to the infinite plane acted on by concentrated forces or dislocations, the other is the holomorphic part, which can be determined by making use of the property of regularity of complex stress functions. The stress intensity factors of the crack can be calculated with different inclined angles of the crack, and the displacement and stress components at an arbitrary position in the half plane can be expressed explicitly.