Al2O3/TiB2/SiCw三元复合材料的力学性能及显微结构

以Al₂O₃为基体,SiC晶须和TiB₂颗粒两种增韧剂,采用热压烧结工艺制备了Al₂O₃/TiB₂/SiC_w三元复合陶瓷材料。研究了热压工艺参数对材料致密度的影响和晶须含量对该复合材料的力学性能和显微结构的影响。结果表明;随晶须含量的增加,该复合材料的热压温度和保温时间需要相应的增加;晶须拔出、裂纹偏转和晶须的桥接为该复合材料的主要增韧机理;随晶须含量的增加,该材料的室温断裂韧性增加;该材料的断裂韧性随温度的升高而呈增大趋势,并且晶须含量越高,材料的高温断裂韧性增幅越大。     

故县水库的开发任务与调度运用

通过对故县水库水文特征分析,论述了水库开发任务和要求。并根据水库的洪水、径流、泥沙特性,拟定了水库防洪运用的控制条件和运用方式,以及水库的兴利运用水位和原则。对水库工程的投资和效益作出了分析和评价。     

高能超声作用下数种金属基复合材料的制备及机制

利用高能超声振动制备了A l/陶瓷, ZA 22/陶瓷(粒子平均直径2L) ,A l/P b (Pb 粒子直径< 25L) 和A l/F eA l₃等金属基复合材料, 弥散相在基体中有良好的分布均匀性。依据超声波对熔体作用时的空化和声流效应, 讨论了上述数种复合材料的制备机制。试验结果显示, 该项技术在制备数类金属基复合材料方面具有广泛的适用性。     

激光与DNA作用系统的随机共振研究

建立了激光与ＤＮＡ分子系统相互作用的Ｆｏｋｋｅｒ－Ｐｌａｎｃｋ方程，通过对该方程的数值研究，发现在绝热近似下，系统发生随机共振，噪声强度，激光振幅和频率协同作用共同制约着生物系统的演化过程，噪声强度在生物系统遗传变异过程中可能起重要作用。     

测量刚体位移的非接触式光电系统

首次提出用标定法测量刚体的线位移和角位移的方法，该方法具有结构简单，性能可靠，非接触性，集成化高，工业上易实现和价格便宜等优点。本文同时还采用了一个小功率激光器为光源，ＣＣＤ为光电转换器件。最后通过相关分析法和数据拟合技术等图象处理技术，提高了整套系统的分辨率。     

Real-time accurate hand path tracking and joint trajectory planning for industrial robots (I)

Previously, researchers raised the accuracy for a robot’s hand to track a specified path in Cartesian space mainly through increasing the number of knots on the path and the number of the path’s segments, which results in the heavier online computational burden for the robot controller. Aiming at overcoming this drawback, the authors propose a new kind of real-time accurate hand path tracking and joint trajectory planning method. Through selecting some extra knots on the specified hand path by a certain rule and introducing a sinusoidal function to the joint displacement equation of each segment, this method can greatly raise the path tracking accuracy of robot’s hand and does not change the number of the path’s segments. It also does not increase markedly the computational burden of robot controller. The result of simulation indicates that this method is very effective, and has important value in increasing the application of industrial robots. Foundation item: Foundation of the Robotics Laboratory, Chinese Academy of Sciences (No. RL200002) Biography of the first author: TAN Guan-zheng, Dr., professor, born in Oct. 1962, majoring in artificial intelligence, robotics and automation.     

工程招投标中的突出问题分析及应对措施

针对我国建设领域招投标活动实施过程中存在的突出问题进行了初步的分析 ,并提出了一些应对措施     

Precipitation behavior of σ phase in fusion zone of dissimilar stainless steel welds during multi-pass GTAW process

The purpose of this study is to investigate the precipitation characteristics of σ phase in the fusion zone of stainless steel welds at various welding passes during a tungsten are welding (GTAW) process. The morphology, quantity, and chemical composition of the δ-ferrite and σ phase were analyzed using optical microscopy (OM), a ferritscope (FS), a X-ray diffractometer (XRD), scanning electron microscopy (SEM), an electron probe micro-analyzer (EPMA), and a wavelength dispersive spectrometer (WDS), respectively. Massive δ-ferrite was observed in the fusion zone of the first pass welds during welding of dissimilar stainless steels. The σ phase precipitated at the inner δ-ferrite particles and decreased δ-ferrite content during the third pass welding. The σ and δ phases can be stabilized by Si element, which promoted the phase transformation of σ→ϱ+λ₂ in the fusion zone of the third pass welds. It was found that the σ phase was a Fe−Cr−Si intermetallic compound found in the fusion zone of the third pass welds during multi-pass welding.     

HIPPS在海洋石油工程中的应用研究

HIPPS系统是一种高集成压力保护系统。介绍了HIPPS系统的特点及功能，并结合HIPPS系统在海洋石油工程中的应用，叙述了HIPPS系统与PSV及ESD系统的主要区别，说明了HIPPS系统给实际的生产操作带来的影响。HIPPS系统在其他行业同样有广泛的应用前景。     

龙滩碾压混凝土重力坝的设计特点

龙滩碾压混凝土重力坝工程量巨大,最大坝高初期建设时为192m,最终为216.5m,技术难度大。设计中针对碾压混凝土施工特点,从枢纽布置、坝体结构、混凝土配合比、温控、施工方案等方面进行了深入的研究,形成了有特色的设计方案,实现了碾压混凝土连续快速施工。