作用于斜坡结构物上海冰荷载的二维计算

海冰荷载是结冰海区海洋工程结构物设计的控制荷载，当结构物迎冰面具有倾斜表面时，海冰将发生弯曲破坏，从而大大降低海冰荷载值。本文针对一个单位宽度的简单斜坡结构物，分析冰板作用于斜坡结构时的破坏机理，提出基本假定，建立一个通用的二维计算模式，并对给定的工程结构物的海冰设计条件进行海冰荷载计算，给出了作用于斜坡结构上的冰荷载值。     

反硝化聚磷机理试验

通过实验研究缺氧反硝化聚磷 ,揭示DPB细菌在厌氧和缺氧交替环境下的厌氧释磷、缺氧反硝化吸磷及CODCr变化规律。结果表明 ,DPB细菌在缺氧条件下可利用NO-3 作最终电子受体进行吸磷 ,其吸磷效果及反硝化速率高于常规脱氮除磷工艺。     

HSE管理体系绩效评估方法研究

通过分析HSE管理体系关键要素,结合模糊数学综合评判的理论和量化评估的思想,建立模糊数学量化评估模型。引入定量化的手段,反映企业实施HSE管理体系的绩效情况并判断其优劣。该评估方法可对HSE管理体系的运行状态进行客观全面的评价,为企业的管理工作指明方向。     

应用Excel模拟高斯烟团模式计算危险气体泄漏

当今由危险气体泄露引发的火灾、爆炸及中毒等恶性环境污染事件已屡见不鲜,人们也已认识到其巨大的危害性,因此在生产和运输过程中进行危险气体环境风险评价是十分必要的。关于危险性气体泄漏扩散模型有许多,但是目前常用的主要是比较成熟的高斯模型。本文在研究危险气体事故泄漏的扩散模式的基础上,利用Excel强大的数据处理功能对常用的高斯烟团模式进行模拟计算。这种方法大大减小了计算量,缩短了工作时间,可为环境风险评价管理、风险工程设计、风险责任保险等领域及应急计划制定、事故抢险工作实施提供有效的工具。     

Fog composition along the Yangtze River basin: Detecting emission sources of pollutants in fog water

To investigate the fog chemistry along the Yangtze River basin, a field observation experiment was performed from Shanghai to Wuhan during November 2015. Fifteen fog water samples were collected by using a three-stage Caltech Active Strand Cloud water Collector(CASCC). The three-stage CASCC was mounted on the board of a ship. PH, electrical conductivity(EC), H_2O_2,HCHO, S(IV), ten inorganic ions, seven organicacids and sixteen trace metal elements were measured in this study. The p H of fog water samples ranged from weakly acidic(pH 4.3) to weakly alkaline(pH 7.05) and the EC ranged from 32.4 to 436.3 μS/cm. The main cations in fog water were NH+4 and Ca~(2+), accounting for 12.35% and 29.07% of those inorganic ions,respectively. In addition, SO_4~(2-) and NO_(-3) contributed to 25.52% and 12.93% to total anion concentrations respectively. Moreover, the dominant kinds of organicacids were formate and oxalate, occupying 45.28% and 28.03% of the total organicacids, respectively. For trace metal elements in fog samples, Al, Fe, Zn, and Ba revealed 34.6%, 16.4%, 19.3%, and 20.9%contributions to these sixteen trace element concentrations, respectively. The results indicated that pollutants were mainly from human activities, including fossil fuel combustion,biomass burning, steel-making, stone quarrying and sand digging. Besides, natural sources including natural background levels and long-range transport of sea salt particles also aggravated the pollution levels in the fog events along the Yangtze River.     

环渤海海冰弯曲强度影响因素分析

本文根据多年环渤海海冰弯曲强度试验结果，分析了诸单因子对海冰弯曲强度的影响，并给出了各海区海冰弯曲强度设计值，海冰的弯曲强度随着应力速度的增加，经过延性，过渡和脆性三个阶段，在过渡区，海冰的弯曲强度达到最大值。随冰温的降低和冰中盐水体积减少，海冰的湾曲强度增大。     

Municipal solid waste management in Beijing City

This paper presents an overview of municipal solid waste (MSW) management in Beijing City. Beijing, the capital of China, has a land area of approximately 1368.32 km² with an urban population of about 13.33 million in 2006. Over the past three decades, MSW generation in Beijing City has increased tremendously from 1.04 million tons in 1978 to 4.134 million tons in 2006. The average generation rate of MSW in 2006 was 0.85 kg/capita/day. Food waste comprised 63.39%, followed by paper (11.07%), plastics (12.7%) and dust (5.78%). While all other wastes including tiles, textiles, glass, metals and wood accounted for less than 3%. Currently, 90% of MSW generated in Beijing is landfilled, 8% is incinerated and 2% is composted. Source separation collection, as a waste reduction method, has been carried out in a total of 2255 demonstration residential and commercial areas (covering about 4.7 million people) up to the end of 2007. Demonstration districts should be promoted over a wider range instead of demonstration communities. The capacity of transfer stations and treatment plants is an urgent problem as these sites are seriously overloaded. These problems should first be solved by constructing more sites and converting to new treatment technologies. Improvements in legislation, public education and the management of waste pickers are problematic issues which need to be addressed.     

Development of a Fish-Based Index of Biotic Integrity for Wadeable Streams in Southern China

With economic development in China, human-induced pressures on aquatic environments have grown and created an urgent need for tools measuring the ecological condition of aquatic systems. However, biological indicators for wadeable streams in China were poorly developed. This study developed and validated a multi-metric index of fish assemblages for wadeable streams of southern China to meet the requirement of the water project which has been carried on in China in recent years. Fifty-seven stream sites were sampled in April–May and November–December 2010 to develop an index of biotic integrity. A set of 45 candidate metrics were evaluated for range, responsiveness and redundancy, resulting in the selection of six metrics for the index: number of native species, number of rheophilic species, proportion of benthic riffle individuals, number of lithophilic species, number of omnivore species, and number of fish per hour sampling. The publicly available census data were used as independent data set to validate our method. Twenty-three sites were assessed as subject to significant (SP) or non-significant pressures (NSP) based on anthropogenic pressure evaluation. Our index performed well in discriminating NSP and SP sites, which suggested that our method could provide an accurate measure for wadeable streams ecosystem condition. We believe this integrated approach would meet the requirements for the water projects of China, and the process of developing the method could be used as reference for managing the subtropical streams in other areas of China or other states.     

Migration,Transformation and Removal of Macrolide Antibiotics in The Environment: A Review

Environmental Science and Pollution Research - Macrolide antibiotics (MAs), as a typical emerging pollutant, are widely detected in environmental media. When entering the environment, MAs can...     

含油污水处理工艺中的污泥及污油回收技术改进措施

针对油田含油污水处理工艺中油水分离设备及缓冲罐等,长期运行积累的污泥若不及时排出,将导致污水中的悬浮固体含量上升和过滤负荷增大、缩短污水处理时间、影响处理效果及水质的问题。寻找合适的工艺技术,去除系统中产生的污油,以提高处理效率、改善最终处理水质。通过采用污泥回收、污油回收等措施,实现了污泥的有效排出,污油的有效回收,改善了处理水质,满足油田的生产需要。