Low-cycle fatigue properties of eutectic solders at high temperatures

This paper details the deformation mechanism and low‐cycle fatigue life of eutectic solder alloys at high temperature (around 0.8T_m). Grain boundary sliding generally nucleates a wedge‐type cavity that reduces the low‐cycle fatigue life of metals. In this study, grain boundary sliding has promoted intergranular failure contributing to the reduction in fatigue life of Sn–Ag–Cu alloy. However, grain boundary sliding has exerted no deleterious effects on fatigue resistance of eutectic Pb–Sn and Bi–Sn alloys. The phase boundary sliding with very fine microstructure induces exceptional ductility in these alloys leading to superior low‐cycle fatigue endurance for theses eutectic Pb–Sn and Bi–Sn alloys.     

Non-destructive testing of rock bolts using guided ultrasonic waves

The research outlined in this paper is aimed at the development of a portable non-destructive testing instrument for evaluating the condition of rock bolts. In applications such as coal mine roof reinforcement, the opportunities for rock bolt inspection are currently limited to destructive techniques such as the pull-out test. It is proposed that guided ultrasonic waves can be used to solve this inspection problem, using a pulse-echo test carried out from the free end of the bolt. Suitable test frequencies have been identified through the use of modelling software, and successful laboratory and site trials have been undertaken. The research has shown that the proposed approach is capable of determining the bolt length, and of identifying major defects such as necking, deformation, and loss of resin encapsulation.     

Prolog逻辑程序的测试方法

Prolog逻辑程序设计语言具有不同于传统程序设计语言的特点.本文根据测试Prolog程序的实践,提出了一系列为Prolog程序生成测试用例的准则.按这些准则测试实际程序效果良好.这是在逻辑程序测试新领域迈出的一步.     

用不稳定试井资料研究油藏储集层流动系统模式：以准东油区为例

从不稳定试井Ｈｏｒｎｅｒ曲线形态分类入手，结合油藏动态特征对油藏储集层流动系统进行分类，并初步确定出各类流动系统的特征参数及其相应的开采特点。根据不稳定试井Ｈｏｒｎｅｒ曲线形态，可以把相应的储集层流动系统划分为三大类（孔隙流动系统、双重介质流动系统、裂缝流动系统）五个亚类。特别提出了双重介质孔缝串并流动系统组合模式。这无论对新区开发方案的编制，还是老区开发政策的制定都具有重要的借鉴参考价值。     

变井储系数的确定方法及其在反褶积分析中的应用

中针对变井储试井分析问题，给出了确定变井储系数及计算续流量的方法，并用反褶积分析积分析方法解释了未出现径向流的早期测压数据，给出了解决早期试井资料分析问题的有效方法。     

油气两相压降数值试井模型及其典型曲线的规律

提出油气两相流动压降试井数字模型的数值解法，用此解法对均质油藏中油气两相流动试井的规律进行了研究，根据实例计算结果，分析油气两相流下典型压降试井曲线的特征，以及油、气的初始饱和度分布，两相黏度比，饱和度梯度、相对渗透率关系对试井曲线的影响和相应的作用机理，首次发现气体的存在会使油气两相试井的压力导数曲线表现出类似于单相流双重介质试井的压力导数曲线的“下凹”特征。     

用试井方法确定注水后地层渗透率的变化

大港油田已进入开发中后期，高含水油田占73％，开发初期的一些参数已不适合现在开发的需要。研究出一套用试井方法确定注水以后地层渗透率变化的方法，对大港油田的增储上产具有重要意义。     

建筑安装与装饰工程施工监理工作的体会

结合对建筑安装和装饰工程施工特点的分析 ,从加大质量控制中事前控制的力度、合理制定进度计划等方面 ,针对性地提出了施工监理工作的重点 ,以确保监理工作的顺利开展。