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981.
王会平 《化工环保》1996,16(4):239-241
研究了聚酯化纤废水中有机污染物乙醛、乙酸、乙二醇含量与COD之间的相关性,确定了COD与上述特征污染物含量的比值,并测定了它们的氧化率,为企业的生产工艺管理和 保管理提供了基础数据。  相似文献   
982.
ABSTRACT: The Grand and Saugeen Rivers in southern Ontario were chosen for study as pilot watersheds under the Pollution From Land Use Activities Reference Group (PLUARG) study. The pilot watersheds have adjacent headwater areas and are physically similar in geology, physiography, and climate. Significant differences in water quality between the watersheds at their outlets are attributed to land use and population differences. The major pollutant sources in the two pilot watersheds were identified as trace elements from urban runoff and point source discharges; phosphorus from agricultural and urban runoff and private waste disposal; chloride from transportation corridors; and sediment and nitrogen from agricultural runoff. Yields at the watershed outlets were similar for suspended sediment and two to three times as high in the Grand River for phosphours, nitrogen, chloride, and lead. The higher phosphorus and nitrogen levels were attributed to larger point source inputs and the higher proportion of agricultural activity, comprising 75 percent of the Grand River basin compared to 64 percent in the Saugeen River basin. Similarly, the higher chloride and lead levels were attributed to an order of magnitude larger population and three times as much urban land in the Grand River basin compared to the Saugeen River basin.  相似文献   
983.
ABSTRACT: An economic analysis of the profitability of adopting solar photovoltaic energy systems for crop irrigation is undertaken. The economic, technological, and political uncertainties surrounding adoption are discussed with reference to their impact on anticipated profitability. On the assumption that the costs of producing photovoltaic modules follows a learning curve characteristic of other inventions, solar systems are likely to be viable for irrigation in some states by mid to late 1980s. A field test in Nebraska is described.  相似文献   
984.
竹涛  张星  王礼锋  朱晓晶  于洋  林军 《化工环保》2019,39(4):367-372
针对钢铁行业有毒有害大气污染物(HAPs)的污染控制难题,以汞和二噁英为典型污染物,论述了钢铁行业HAPs排放特征及控制技术,介绍了HAPs的管控机制,提出了钢铁行业HAPs减排建议。  相似文献   
985.
For over a century, western economic development has depended upon the use of combustible hydrocarbons for its energy needs. The 20th century saw the prolific exploitation of fossil hydrocarbon sources (coal and oil) which are finite and exhaustible. There is a clear need for society to conserve such non-renewable resources. In addition to conservation, a wholesale switch to renewable energy sources should be seen as the first research and development priority. In the interim, moving towards a crop-based fuel economy appears to be a good alternative to provide the necessarily dramatic changes in lifestyle and mindset that would be required of consumers, for a wholesale shift away from hydrocarbon combustion. Before programs and policies designed to address the need for an interim or alternative energy and materials economy are put into place however, it is important to understand the barriers and opportunities put forth by society itself. Conventional frameworks designed to understand this type of change are of limited assistance. This paper argues that institutional thinking is a very useful tool in addressing these types of environmental problems.  相似文献   
986.
Semi-natural calcareous and acidic grasslands are known to be sensitive to increased atmospheric N deposition. However, the fate of pollutant N within these systems is unknown. This paper reports on the first studies to determine the fate of added N within a calcareous and an acidic grassland subject to long-term simulated enhanced N deposition. Intact soil/turf cores were removed from field plots treated for six years with enhanced N deposition (ambient +0, +35 and +140 kg N ha–1 year–1). Cores were inserted into lysimeters and output fluxes of N were monitored in detail. Complete N budgets—calculated from the N flux data—showed considerable accumulation of N within the treated grasslands, up to 76% and 38% of pollutant N in the calcareous and acidic grasslands respectively. In the second study, the short-term (21 day) fate of pollutant N was determined by tracing 15N labelled ammonium nitrate (+35 kg N ha–1 year–1) though the acidic and calcareous lysimeters into plant, soil and leachate pools. Up to 91% and 59% of 15N was recovered in soils and vegetation of the calcareous and acidic grasslands respectively, with negligible amounts recovered in soil extractable ammonium and nitrate (<0.3%) and in leachate (<0.02%). This rapid short-term immobilisation of pollutant N supports the long-term accumulation of the element calculated from the N flux study.  相似文献   
987.
本文研究PAN-ACF的主要结构参数,探讨了ACF对SO2的物理吸附、脱附性能以及传质机理,得出传质过程为内扩散控制,并计算出扩散系数D值约为活性炭D的50-170倍。  相似文献   
988.
ABSTRACT: A comparative study of the concentration of asbestos fibers in drinking water supplies of southeastern Quebec was undertaken to assess the relative contributions of fibers by asbestos-bearing railway ballast and naturally occurring asbestos deposits. Water samples were taken from areas where one or the other potential sources or neither potential source was present. In addition, rainwater samples were taken to assess the importance of atmospheric contributions. The sampling design accounted for potential variations in fiber counts due to the season, location and analytical procedures. Fiber concentrations were estimated from counts made on a JEOL 100CX scanning transmission electron microscope and statistically compared among areas. These levels were then compared with levels found in other areas of Canada and the United States. The results indicate that the rail ballast could be contributing statistically (albeit marginally) significant quantities of fibers to water supplies during the summer but not in the spring. Estimated concentrations in water supplies ranged between 1.7 × 106fibers/liter and 147.8 × 106fibers/liter. Fiber levels in samples taken during the spring were significantly higher and more variable than those taken during the summer. The presence of fibers in rainwater samples at concentrations of 1.9 × 106fibers/liter, 18.3 × 106fibers/liter and 23.7 × 106fibers/liter suggests that atmospheric transport may play an important role in contributing fibers to regional systems. Fiber levels found in these systems are not unique when compared to levels observed elsewhere in North America.  相似文献   
989.
以南京化学工业(集团)公司为例,介绍在企业中实行排污许可证制度,可有效地控制污染物排放,并改变以往污染物排放的末端管理为生产全过程控制,强化了环保法制观念,协调了管理工作与监测工作之间的关系,使环保管理工作由被动变成主动。  相似文献   
990.
沿海油田污染物入海通量及优化管理   总被引:3,自引:0,他引:3  
胜利油田所在的黄河三角洲诸条河流按入海类型分为三种形式:设有防潮闸的感潮河;设有排涝站的入海河;直流入海的感潮河。按照各河流入海段面、流速、流量和水体污染物浓度,建立起各种感潮河污染物入海通量模式,计算结果说明沿海油田排放的石油类污染物入海通量为1456t/a,COD入海量为5720t/a。根据各条入海河流不同功能和污染物入海量,按照国家地表水质标准,制定出入海河流环境组合目标,用总量控制方法提出污染源削减要求,以保证黄河三角洲沿海滩涂环境质量。并以污染物入海通量、河流径流量、污染物自净系数和污染物削减量等因子建立各条河流优化管理模型,为保护环境提供对策。  相似文献   
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