Express Method for Estimation of Tensile Strength and Crack Resistance of Brittle Media

The procedure is proposed for estimating the crack resistance and tensile strength of rocks by the results of experiments on disk samples with holes. The gradient approach to the strength problem is employed in processing the experimental data.     

标准日本语网上教学系统的设计与实现

网络远程教育是网络技术与教育相结合的产物。本文介绍基于ASP／AD0网络数据库访问技术的适用于远程教学环境的《标准日本语》网上教学系统的设计思想及部分实现技术。     

Evolution of grain structure in thin film reactions

In this paper, we examine, both experimentally and theoretically, the kinetics of formation and microstructure of product phases in thin film reactions, using the Nb/Al and Ti/Al systems as our prototypes. The results of calorimetry and microscopy studies are interpreted using simple kinetic and morphology models. In particular, the kinetic models employed here focus on the nucleation and growth components of the phase formation process and the morphology models provide a starting point for the classification of product grain structures. An erratum to this article is available at .     

Nonlinear electrical transport in K-TCNQ at low temperatures

A remarkable nonlinearity has been observed for electric transport in K-TCNQ (potassium tetracyanoquinodimethane) quasi-one-dimensional conductor. The negative differential resistance region appears afterV _m (turn over voltage), beyond which voltage goes down with increase of current. A possible mechanism is discussed in terms of dynamics of charged solitons and domain walls in one-dimensional molecular stacks of these types of crystals.     

Exchange and oxidation of CO on O-predosed Rh---Al2O3 and Rh---CeO2 catalysts

Exchange and oxidation of C¹⁶O were investigated at 450°C on ¹⁸O-predosed Rh and Pt catalysts supported on A1₂O₃, CeO₂ and CeO₂-Al₂O₃. In all cases, a rapid exchange of C¹⁶O with the surface can be observed. CO oxidation leads to C¹⁶O₂, C¹⁶O¹⁸O and C¹⁸O₂. Significant formation of C¹⁶O₂ is due to the relatively high ¹⁶O coverage in reaction resulting from the C¹⁶O exchange and from an exchange between O surface species and ¹⁶O internal atoms. Hydrogen is also formed via a water-gas shift reaction (CO + surface OH) in higher proportion on CeO₂-containing catalysts than on A1₂O₃. Chlorine inhibits all the reactions (exchange, oxidation and WGS) and particularly the internal exchange.     

TiAl基合金表面改性对高温抗氧化性的影响

研究了渗碳处理ＴｉＡｌ基合金试样的高温氧化行为，发现渗碳处理可以在ＴｉＡｌ基合金试样表层形成致密的多层结构的渗碳层，并发生表层Ａｌ、Ｔｉ重新分配。致密的渗碳层具有良好的高温抗氧化性和高温热稳定性，同时，Ｔｉ、Ａｌ重新分配形成的富Ａｌ最外层也能进一步提高合金的抗氧化性。     

智能网的计算机技术

文章剖析了应用于智能网的计算机技术，阐述智能网和计算机技术的关系。     

短周期超晶格AlP／GaP能带结构的转变及其带间的光跃迁

介绍了间接跃迁的半导体ＡｌＰ与ＧａＰ形成的超晶格，由于零折叠效应，实现了能带由间接带隙向直接带隙的转变，从而增加了带间的光跃迁几率，并推导了该几率的表达式。     

二元复合驱采出液矿场处理试验

利用研制的二元复合驱采出液矿场处理装置，对辽河油田兴28块兴191井采出液进行了矿场处理试验。结果表明，采用适宜的破乳剂及处理工艺技术，可以使矿场采出液处理达到净化油含水≤0．5％的指标。