液氯泄漏事故模拟分析

针对1996年1月21日在西班牙发生的一起液氯泄漏事故的后果进行了模拟分析。模拟分析结果同事故实际所造成的后果是一致的。表明采用基于数学模型的事故后果模拟分析具有一定程度的可靠性。对于救灾和对重大危险源编制应急事故预案有一定程度的指导意义。     

Effect of soil solids concentration in batch tests on the partition coefficients of organic pollutants in landfill liner-soil materials

 The effect of the soil solids concentration in batch tests on the measured values of the partition coefficient (K _p) of organic pollutants in landfill liner-soil material was investigated. Since this study was based on the results of batch and column tests conducted independently, there were limitations to the conclusions derived. The organic compounds tested were benzene, methylene chloride, toluene, trichloroethylene, and p-xylene. The results of this study showed that as soil solids concentrations increased, the measured K _p values of these organic compounds strongly decreased. The observed values of K _p stabilized when the soil solids concentration was above a certain value. Typical K _p values obtained from batch tests conducted under high soil solids concentrations were close to those obtained from column tests. It was concluded that the K _p values of organic compounds measured under low soil solids concentrations, i.e., less than 100 g/l, may not correctly simulate the field situation. Consequently, the values of K _p obtained with low soil solids concentrations can result in an overestimation of the retardation factor of the landfill liner material. Received: March 14, 2002 / Accepted: August 25, 2002     

采掘诱发地震的成因及对策

根据煤或岩体的赋存特征及采动后的受力特点，将采矿及掘进等工程进行过程中诱发的地震灾害分为三类，即完整煤岩体受压应力作用的失稳、顶底板受拉应力型地震及断层走滑受剪型诱发地震。文章在分别分析其成因的基础上，研究了采矿诱发三种类型地震的发生条件，提出了防治发生诱发地震的对策。     

Review of information on pesticide residues in the Canadian environment

Summary Pesticide residues in soil, water, food, wildlife and other media have been analysed in several monitoring studies. The purpose was to establish the distribution of these residues across a defined area, ascertain their trend over a specific period and use the results to assess environmental compliance and safety. In the present review the availability of information on pesticide residues in various Canadian environmental components was sought. With the possible exception of localized pesticide contamination of some private water supply wells, ground and surface water, most analyses revealed concentrations below guideline limits. Only a few cases were reported of mishandling, misuse and poisoning from pesticides. Continuing surveillance programmes and in-depth and well-organized monitoring studies, with special focus on areas that are vulnerable to contamination, by both provincial and federal governments, are largely responsible for the encouraging results. This experience in the control of pesticide use and monitoring of residues in the environment should be of particular interest in developing countries.Dr A.Y. Sangodoyin is a senior lecturer in the Department of Agricultural Engineering at the University of Ibadan. He was recently involved in a study visit to the University of Alberta, Edmonton, Alberta, Canada T6G 2G7, where his co-author Dr D.W. Smith is a member of staff in the Department of Civil-Engineering.     

煤层气勘探开发和利用的环境影响分析

煤层气是煤层中自生自储的一种非常规天然气，其成分主要是甲烷。与煤和石油比较，煤层气是一种清洁能源，因此加快煤层气的开发和利用，能改善能源结构，缓和能源紧张状况，减少环境污染。根据煤层气的特点，详细分析了其对于大气环境、水环境以及土壤、植物的影响因素后指出：开发利用煤层气对大气环境的影响利大于弊，而对水体、土壤、农作物等则产生一系列不利影响。     

锆改性纳米TiO2的光催化性能研究

用溶胶-凝胶法制备了锆改性纳米二氧化钛光催化剂,并用XRD、UV-vis、BET等测定技术对所制得的粉体试样进行了表征.同时以甲基橙及苯酚为模拟污染物,评价了改性后纳米二氧化钛的光催化性能,发现其光催化活性大大高于未改性二氧化钛粉体,并得出当n(Zr)/n(Ti)=5/300时,锆改性纳米二氧化钛样品的光催化活性最高.     

玻璃纸生产废气中CS2和H2S的治理

阐述了玻璃纸生产中CS2和H2S废气产生的原理，介绍了该废气处理的现状，总结了目前普遍采用的冷凝法、活性炭吸附法、活性碳纤维吸附法、改性活性炭吸附法、螯合铁氧化法、吸收-吸附法等处理方法的特点和效果。介绍了一种先采用螯合铁氧化法、再采用冷凝法、最后采用活性炭吸附法的综合处理工艺，可使废气达标排放。     

Enzyme-Retted Flax Fiber and Recycled Polyethylene Composites

Municipal solid wastes generated each year contain potentially useful and recyclable materials for composites. Simultaneously, interest is high for the use of natural fibers, such as flax (Linum usitatissimum L.), in composites thus providing cost and environmental benefits. To investigate the utility of these materials, composites containing flax fibers with recycled high density polyethylene (HDPE) were created and compared with similar products made with wood pulp, glass, and carbon fibers. Flax was either enzyme- or dew-retted to observe composite property differences between diverse levels of enzyme formulations and retting techniques. Coupling agents would strengthen binding between fibers and HDPE but in this study fibers were not modified in anyway to observe mechanical property differences between natural fiber composites. Composites with flax fibers from various retting methods, i.e., dew- vs. enzyme-retting, behaved differently; dew-retted fiber composites resulted in both lower strength and percent elongation. The lowest level of enzyme-retting and the most economical process produces composites that do not appear to differ from the highest level of enzyme-retting. Flax fibers improved the modulus of elasticity over wood pulp and HDPE alone and were less dense than glass or carbon fiber composites. Likely, differences in surface properties of the various flax fibers, while poorly defined and requiring further research, caused various interactions with the resin that influenced composite properties.