氮污染在地下水中迁移、转化规律的研究

氮及其化合物是目前地表水和地下水的一个重要污染源。本文选取不同土质作为渗透介质,通过室内土柱实验,得出不同深度的土层对不同浓度的NH4+-N和NO3--N的去除率,及不同土层对同一浓度NH4+-N和NO3--N的去除率。同时得出,无论哪种地下土质对氨和硝酸盐的阻截能力都较弱,对突发污染恢复力也同样较弱。     

Effects of Vehicle Impact Velocity and Front-End Structure on Dynamic Responses of Child Pedestrians

To investigate the effects of vehicle impact velocity and front-end structure on the dynamic responses of child pedestrians, an extensive parametric study was carried out using two child mathematical models at 6 and 15 years old. The effect of the vehicle impact velocity was studied at 30, 40, and 50 km/h in terms of the head linear velocity, impact angle, and head angular velocity as well as various injury parameters concerning the head, chest, pelvis, and lower extremities. The variation of vehicle front-end shape was determined according to the shape corridors of modern vehicles, while the stiffness characteristics of the bumper, hood edge, and hood were varied within stiffness corridors obtained from dynamic component tests. The simulation results show that the vehicle impact speed is of great importance on the kinematics and resulting injury severity of child pedestrians. A significant reduction in all injury parameters can be achieved as the vehicle impact speed decreases to 30 km/h. The head and lower extremities of children are at higher injury risks than other body regions. Older children are exposed to higher injury risks to the head and lower leg, whereas younger ones sustain more severe impact loads to the pelvis and upper leg. The results from factorial analysis indicate that the hood-edge height has a significant effect on the kinematics and head impact responses of children. A higher hood edge could reduce the severity of head impact for younger children, but aggravate the risks of head injury for older ones. A significant interaction exists between the bumper height and the hood-edge height on the head impact responses of younger child. Nevertheless, improving the energy absorption performance of the hood seems effective for mitigating the severity of head injuries for children.     

城市污水厂污泥间壁热干燥过程实验研究

分析污水厂污泥间壁热干燥过程的影响因素 ,并确定过程的关键设计参数。研究以间隔实验为基本手段 ,并进行了污泥间壁热干燥过程数学模型的推导。认为 :壁温和泥层厚度是过程的主要影响因素 ,由实验数据确定的过程比总传热系数 K是设计的关键参数 ,在适宜条件 :壁温 16 0℃ ,泥层厚度 1.0 cm时 ,其值为 6 5 .6 (k J/ m2·℃· h)     

大气固定污染源监测分析方法的标准化研究

论述了大气监测分析方法标准化研究的特点，内容，样品采集方法和保存条件，样品预处理方法和测定条件，干扰检验，方法的基本特征参数第一轮测定，实际样品的测定等问题。     

脱硫废水处理试验研究

湿法烟气脱硫工艺产生的废水中含有大量污染物 ,严重危害环境和人民的身体健康。试验研究了脱硫废水的处理工艺 ,研究探讨中和沉淀、硫化物沉淀和絮凝沉淀的处理药剂、最佳加药量和反应条件 ;并进行动态模拟试验     

基于安全性目标的车辆维护周期数学模型研究

本研究旨在建立一个相应于不同的给定的行驶安全性的车辆最优维护周期数学模型，同时，利用汽车制动系、转向系等系统或装置的运行故障分布参数，求出了不同安全性水平下该数学模型的解。还依据原始数据，给出了同样基于行驶安全性目标的汽车维护周期允许上限。本研究结果可用于指导汽车维护工作，而且对保证或提高在用车辆的行驶安全性具有重要的作用     

Framework for environmental impact analysis—with special reference to India

This article reviews the present status of environmental impact analysis (EIA) with special reference to India. In India, legislation already exists that makes EIA mandatory for every new project proposal. Critically analyzing the shortcomings of the present EIA practices, this article proposes a new framework to conduct an EIA, emphasizing that it should be part of the environmental management of the area or region. Among other things, we suggest the following important points: (1) that a comprehensive database of the region be developed for use for conducting an EIA; (2) that emission standards for the proposed industry be set and the existing standards for old industries be reviewed; (3) that a directory of experts be developed; and (4) that the Department of Environment should take responsibility for conducting EIA studies by forming a study team and an evaluation team for every EIA study with members drawn from the directory of experts.     

使用HAZOP分析法对重大事故进行调查分析

重大事故不仅对当事人造成伤害,对其家庭、国家及社会都要蒙受相当大的损失。故选用合理、有效的系统安全分析方法,对事故致因进行调查分析在事故处理过程中具有关键作用。笔者介绍一种系统安全分析方法,称为危险与可操作分析(HazardandOperabilityStudy,简称HAZOP),该法在其他先进国家已采用多年,但在国内却很少使用。应用HAZOP法对某化工厂失控反应事故进行系统安全分析,研究的侧重点是工艺过程和操作步骤的各种具体数值,它的基本过程就是以引导词为引导,对过程中工艺状态的变化(偏差)加以确定,找出装置及过程中存在的危害。引导词的主要目的之一是能够使所有相关偏差的工艺参数得到评价。HAZOP分析法具有系统性、结构性、创造性和前瞻性的优点,在系统安全分析中具有特别优势,值得推广应用。     

人体工程学及其未来

人体工程学在当今世界倍受瞩目,这是历史发展的必然。本文从这门学科的发展历程及它的研究领域展开论述,指出人体工程学的基本思想就是以人为本。随着科技的飞速发展,以人为本已经成为趋势理念,人体工程学已由自然状态走向自觉状态,文中引用很多实例证明了它的应用价值。在可持续发展的未来,人体工程学具有广阔的发展前景。     

环境工程学研究的新思考

本文在环境工程特征分析的基础上,运用现代系统科学原理,以环境理念和工程视角,阐述了环境工程学新领域、新思维和新方法的研究进展,进一步明确了环境工程学在经济社会发展中的重要作用。