城市建设的休克疗法——大连现象解说

在启动大规模的现代化建设的进程中，应对发展中听中型城市实施“休克疗法”，强调性终止城市发展的无序而缓慢的自然进程。选择短暂的“回归”或“中断”历史的调整时，应以能否适当地的历史文化特质从而把握当代的发展机遇为依据。     

激光诱导激波在氮气中的传播

实验观察了强激光脉冲击穿氮气诱发激波及其传播过程，用爆炸波模型讨论了激波的产生和传播，给出了激波传播的基本规律，对实验结果作出了满意的解释。     

Thermal shock and thermal fatigue study of ceramic materials on a newly developed ascending thermal shock test equipment

A test equipment was designed to study thermal shock and thermal fatigue of ceramic materials subjected to fast heating (ascending). The equipment was designed to generate thermal stress in a test specimen by heating one surface of it by an oxy-hydrogen flame while cooling the opposite surface. The sample cracked when thermal stress exceeded its mechanical strength. The in situ crack formation was detected by an acoustic emission system coupled to the set up. The hot zone temperature was measured by an infra red pyrometer. The equipment was also designed to run thermal fatigue test cycles in automatic mode between two selected temperatures. The temperature and thermal stress distribution in the test specimen were modelled using finite element software. The effect of temperature distribution of the top and bottom surfaces on thermal stresses was studied. It was observed that the thermal stress is very sensitive to the temperature distribution on the top surface and maximum near the periphery of the top surface. This was in agreement with the experimental results in which the cracks were originated from the periphery of top surface. It was also observed that the failure temperature was higher for thicker samples.     

复合射孔枪枪身材料动态本构关系的试验研究

为确定复合射孔枪枪身材料32CrMo4钢在井下高温、高加载率工作环境下的动态性能,利用MTS试验机和分离式Hopkinson冲击压杆装置做了应变率为0.001、1000和3000/s,温度为294、373、473和573K的单轴动态压缩试验,得到32CrMo4钢各组温度及应变率下的流动应力-应变曲线。拟合得到该钢Johnson-Cook本构关系模型所需的5个参数,模型拟合曲线与试验曲线吻合。     

液态挤压在铝合金减震筒上的应用：液态挤压比压值对制件性能影响的分析

指出了压力铸造及热挤压工艺生产铝合金减震筒的缺点，阐述了液态挤压的特征，介绍了液态挤压在减震筒上的应用，分析了比压值对制件性能的影响。     

Thermal Shock Behavior of Porous Silicon Carbide Ceramics

Using the water-quenching technique, the thermal shock behavior of porous silicon carbide (SiC) ceramics was evaluated as a function of quenching temperature, quenching cycles, and specimen thickness. It is shown that the residual strength of the quenched specimens decreases gradually with increases in the quenching temperature and specimen thickness. Moreover, it was found that the fracture strength of the quenched specimens was not affected by the increase of quenching cycles. This suggests a potential advantage of porous SiC ceramics for cyclic thermal-shock applications.     

UL简介与CCL认可

本文从六个方面对UL的基本知识作了一个简要的概述及CCL认可过程的介绍,希望能为业界同仁提供一个参考方向。     

应变式压力传感器特性补偿和应用

讨论了用动态补偿数字滤器对应变压力传感器的动态特性进行补偿，使之提高测量精度并能用于爆炸冲击波测量的一种方法。实验结果与经验值比较，补偿前．后对比、测量精度有明显提高，说明在一定条件在变式测压系统也可用于爆压的测试。     

含有复合阻尼结构的压力波制冷机振荡管内流动分析

通过对含有复合阻尼结构的压力波制冷机振荡管内的流场分析，详细讨论了激波在接受管内的行为，数值计算同时表明：含有两道复合阻尼结构加上激波吸收腔完全可以将激波降低到工程上可以接受的程度。