Long-term measurements of the concentrations of halocarbons in an urban area of Kraków, Poland

The results of the measurements of the concentrations of freons (F-11 and F-113), chloroform (CHCl₃), trichloroethane (CH₃CCl₃) and carbon tetrachloride (CCl₄) in air are presented. The data concern concentration measurements that have been conducted in Krakow since half way through 1997 to the end of 1999. The mean monthly values of these concentrations have been compared with the data from Mace Head, the station situated at a similar longitude as Krakow. It has been concluded that, in the observed period of time, the concentrations of the pollutants in Krakow are higher than in Mace Head. The mean monthly concentrations of F-11 and CCl₄ decrease in Krakow faster than in Mace Head (2.5 and 3.3 times, respectively). The concentrations of CHCl₃ and CH₃CCl₃ decrease at both locations, but the change is greater in Krakow. In Krakow, the observed increase of F-113 is 0.13 ppt/month and has an opposite trend than in the same period at Mace Head.     

Occurrence of Lawn Care and Agricultural Pesticides in the Don River and Humber River Watersheds (1998–2002)

Between 1998 and 2002, surface water samples were collected from several sites in the Don River and Humber River watersheds, both tributaries to Lake Ontario, and analyzed for a variety of pesticides, including those used for urban lawn care. Analyses included 152 pesticide active ingredients and eight metabolites. Samples were collected during base flow periods (i.e., dry events) and rainfall events (i.e., wet events). The objectives of the study were to determine which pesticides were detectable, whether there was a difference in the detection frequency between the two watersheds and between upstream and downstream in each river, and whether precipitation influenced the frequency of detection. Eleven pesticides and one metabolite were detected in surface waters of the Don and Humber rivers or their tributaries, with approximately 72% of samples containing at least one pesticide attributable to lawn care use. The pesticides and pesticide metabolite detected in this study included 2,4-D, atrazine, bromacil, carbofuran, chlorpyrifos, cypermethrin, diazinon, dicamba, MECOPROP, metolachlor, metribuzin, and an atrazine metabolite (des-ethyl atrazine). Four pesticides exceeded federal or provincial water quality guidelines/objectives. Diazinon exceeded the provincial water quality objective in 28% of the samples taken. For the three other pesticides (atrazine, carbofuran and chlorpyrifos) exceedance of a water quality criteria occurred in less than 1% of the samples.     

上海市松江新城突进式发展的体制创新与探索

本文用理论和现实的案例分析详细阐述了“经营城市”的六项特征和“三赢”的理念 ,简要介绍了松江新城在财政不出一分钱的情况下为取得突进式发展所采取的制度创新和探索 ,并总结了两点如何树立规划权威性的经验。     

论城市轨道交通传输网络的设计方案

对城市轨道交通通信系统的传输网络需求进行了分析，对各种传输制式进行了比较，提出了城市轨道交通通信系统传输网络的最佳解决方案。     

诸暨市老城区合流制排水系统的改造

对诸暨市城中区三个不同区域合流制排水系统的地形条件、污染源性质、污水量、道路现状、施工条件及工程资金情况等进行综合分析后，分别采取了不同的改造措施，其实施效果良好。     

探讨低收入阶层住区建设的公共政策

探讨了低收入阶层住区建设的现状及弊端，从旧城改造、新城建设及住房政策三方面对解决低收入阶层住区建设问题的对策进行了研究，以妥善解决低收入阶层的住房问题，从而达到构建和谐社会的目的。     

基于非确定性思考下的城市规划新思维探讨

通过对城市规划编制与实施过程中的问题分析，提出非确定性城市规划思想的理念以及非确定性规划思想与确定性规划思想的差别，并在分析非确定性规划思想内涵的基础上，提出非确定性规划思想指导下的城市规划的新程式。     

THE STICKY ISSUES OF DRYING

Unconrolled agglomeration of particles and adhesion of the particulate mass to wall surfaces are common severe problems in many drying operations. This paper reviews the mechanisms of interparticle and particle-surface attraction as well as the theory and the existing tests for characterising powders in terms of internal strength, wall friction and adhesion. The usefulness of the information obtained from these tests in dryer design and operation is critically reviewed. The importance of powder stickiness in various types of dryers is discussed and established methods of combating the problem are presented Recommendations an made for further research in the area of powder cohesion and adhesion.     

市内通信电缆绝缘电阻特殊要求的实现和措施

本文对市内通信电缆的各生产过程进行分析、研究和控制 ,从而提出了解决绝缘电阻特殊要求的方法 ,以及改进的措施。     

辽宁省城镇居民生活用水定额

本文分析了城镇居民生活用水的特点,介绍了辽宁省城镇居民生活用水定额制定的原则、方法。通过对全省县级以上城镇居民生活用水情况的调查,制定适合辽宁省实际情况的城镇居民生活用水定额。