苏州某燃煤电厂气载放射性排出物环境影响评价

根据苏州某大型燃煤电厂烟尘排放所致周围环境近地面空气中天然放射性核素的浓度和地面沉积量及其分布,估算了该厂气载放射性排出物对厂区周围半径100km范围内公众居民经蔬菜、农作物食入,飘尘吸入和地表γ沉积的内、外照射途径所致的归一化人均有效剂量当量和归一化集体有效剂量当量。估算结果表明,最大污染浓度位于下风向SW-NW区间距烟囱1km处;归一化人均有效剂量当量是4.17×10~(-4)Sv/GWa;对厂区周围半径100km范围内2.1×10~7公众居民的归一化集体有效剂量当量是40man·Sv/GWa。     

半刚接钢框架内填RC墙结构滞回性能试验——局部性能分析

通过对3榀2层1跨的半刚接钢框架内填钢筋混凝土剪力墙结构(简称PSRCW)的低周反复荷载试验,重点研究结构局部受力性能,分析PSRCW结构中半刚性节点及内填墙的破坏模式与变形能力、钢框架与内填墙界面分离及滑移、以及两者之间的内力分配等局部性能。分析结果表明:内填墙的存在对半刚接节点的变形能力具有一定刚化影响,降低了节点的转动能力;在确保抗剪连接件在加载过程中不发生疲劳断裂的前提下,不同类型的抗剪连接件对PSRCW结构性能影响不明显;同时,为了避免抗剪连接件疲劳断裂,建议内填墙采用低强度等级的混凝土,或采用U形弯筋或槽钢连接件。在设计荷载水平,内填墙分担80%水平剪力,钢框架分担60%的倾覆力矩。     

石化阀门用防爆O形圈RGD检测治具设计

概述了RGD检测技术与现状。结合高温高压易燃石化苛刻工况与RGD防爆检测要求,从RGD治具容器、壳体壁厚、容积、防爆O形圈的安装配合以及O形圈沟槽的设计与计算等方面进行深入研究,解决了RGD治具试样O形圈预压缩率难以控制、RGD检测准确性不足甚至失效以及RGD试验过程中试验介质无法充分渗入O形圈以与O形圈爆破失效后的泄漏危险等难题,顺利设计开发了防爆O形圈RGD检测治具。     

实现清洁生产工艺的探讨--为苏州的环境更美好和苏印的可持续发展

论述了工厂搬迁实施清洁生产工艺的规划和各种行之有效的对策及举措。     

Language Features of Contractual English

As contract is a written document in which what the parties are concerned and agree is stated, the simplest way to understand the drafting of the contract is, from the author's point of view, to be well acquainted with contractual language. Therefore, this article is intended to give a brief account of the language features of contractual English.     

不同电源频率下的电机、电器使用

文章主要分析了电源频率对电机、电器主要性能的影响,并指出50Hz与60Hz电器在使用中应注意的几个问题。     

弯管的造型及其投影图的计算机绘制

本文运用实体扫描的几何造型技术,建立了弯管的数学模型,并根据微分几何的有关知识,推导出它们的投影轮廓线的方程式。利用这些方程式,能由计算机快速、准确地绘制出它们的透视投影图和轴测投影图。本文适用于等径和变径的多种弯管。     

Configuration Selection for Reconfigurable Manufacturing Systems by Means of Characteristic State Space

The configuration selection for reconfigurable manufacturing systems(RMS) have been tackled in a number of studies by using analytical or simulation models. The simulation models are usually based on fewer assumptions than the analytical models and therefore are more wildly used in modeling complex RMS. But in the absence of an efficient gradient analysis method of the objective function, it is time-consuming in solving large-scale problems by using a simulation model coupled with a meta-heuristics algorithm. In this paper, a new approach by means of characteristic state space is presented to improve the efficiency of the configuration selection for an RMS. First, a characteristic state equation is set up to represent the input and the output resources of each basic activity in an RMS. A production process model in terms of matrix equations is established by iterating the equations of basic activities according to the resource flows. This model introduces the production process into a characteristic state space for further analysis. Second, the properties of the characteristic state space are presented. On the basis of these properties, the configuration selection in an RMS is considered as a path-planning problem, and the gradient of the objective function is computed. Modified simulated annealing(SA) is also presented, in which neighborhood generation is guided by the gradient to accelerate convergence and reduce the run time of the optimization procedure. Finally, several case studies on the configuration selection for some actual reconfigurable assembly job-shops are presented and compared to the classical SA. The comparison shows relatively positive results. This study provides a more efficient configuration selection approach by using the gradient of the objective function and presents the relevant theories on which it is based.     

激光直写法制备仿刚毛微纳阵列的研究

提出一种采用激光直写技术制备微纳阵列的新方法来制备仿壁虎刚毛二级结构微阵列。该制备过程由计算机控制完成。实验制备出具有不同几何尺寸的一级结构阵列,并在此基础上探索制备二级结构微阵列的三种方案,其中,“自上而下”的方案通过对曝光时间和显影时间的控制使第二级结构扎根于第一级结构中,有效提高了两级结构间的连接强度。制备实验的同时,分析了曝光时间、显影时间等参数对阵列制备的影响。激光直写制备微纳阵列的方法具有高效率、低成本的优点。     

国产600MW核电机组主调门油动机活塞杆断裂原因分析

某国产600MW核电机组在停堆检修过程中,发现位于汽轮机高压缸主蒸汽入口主调门油动饥活塞杆已经断裂．通过分析活塞杆的材料、显微组织、力学性能和断口等,并结合活塞杆制造的资料等信息,分析了造成活塞杆断裂的原因．