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261.
在介绍污水处理厂的基础建设程序及环境影响评价的发展概况的基础上,以京溪污水处理厂为例,指出城市规划部门在规划制定过程中,应加大环境影响评价工作的深度,以使污水厂的建设程序得以顺利开展。同时指出城市的卫生、地质、规划、国土、环保等职能部门在制定本部门的法规政策过程中,应发挥协调机制,在工程建设的相关方面达成共识,以确保污水处理厂等市政项目的建设顺利开展,促进城市更好的发展。  相似文献   
262.
碳酸锶生产中"三废"综合利用研究   总被引:2,自引:0,他引:2  
介绍了碳还原法生产碳酸锶过程中"三废"的主要成分;提出了用克劳斯燃烧法和吸收氧化法生产硫磺,用直接合成法和4级联合吸收法生产硫脲综合利用废气的途径;提出了2种治理废水方案,不仅达到脱硫、脱氮、降解有机物目的,而且还可得到硫磺、碳酸氢氨副产品;探讨了锶渣在砖、水泥的生产及公路工程建设中应用的可行性.  相似文献   
263.
分析了国际静电放电测试研究领域现有的各种测试研究装置特点,为克服已有测试装置缺陷本团队研发设计出一种全新的静电放电测试研究系统—电极移动速度效应检测仪。对其结构设计特点、功能进行了分析。我们研制的新型静电放电测试系统兼具实现真实直线运动准确调节和多环境因素可控的优点,彻底解决了困扰国际电磁兼容静电放电研究领域电极需高速向靶移动放电与避免强烈撞击损坏仪器的难题,实现了对多种因素影响逐一准确控制,为静电放电性质更为深入广泛的研究提供了新的手段和平台。  相似文献   
264.
We examined the influence of several hydrological and meteorological parameters on the migratory movements of ayu Plecoglossus altivelis altivelis in central Japan. When comprehensively evaluating rivers and ayu behaviour on a catchment scale, the subjects of analysis typically include human activities and hydrological and meteorological phenomena. However, limiting analyses to such factors may be too restrictive when human activities are being conducted. Accordingly, we incorporated a biological viewpoint into the evaluation method, analysing hydrological data (river discharge, river water temperature, sea water temperature) to determine watershed characteristics and examining the relationship between these characteristics and the habitat conditions of ayu. Then we constructed a numerical model for ayu migratory runs that incorporated ayu ecology and watershed characteristics. Analyses of ayu movements from a lower estuarine dam demonstrated that downstream displacements were associated with high water flows of more than 200 m3 s−1 at the beginning of summer. We conclude that it is important to consider the effects of environmental parameters on the movements of different fish species to understand the causes of spatial variation in fish distribution in lowland rivers.  相似文献   
265.
Organic matter and nutrients in municipal sewage sludge (SS) and chicken manure (CM) could be recycled and used for land farming to enhance fertility and physical properties of soils. Three soil management practices were used at Kentucky State University Research Farm, Franklin County, to study the impact of soil amendments on kale (Brassica oleracea cv. Winterbar) and collard (Brassica oleracea cv. Top Bunch) yields and quality. The three soil management practices were: (i) SS mixed with native soil at 15 t acre?1, (ii) CM mixed with native soil at 15 t acre?1, and (iii) no-mulch (NM) native soil for comparison purposes. At harvest, collard and kale green plants were graded according to USDA standards. Plants grown in CM and SS amended soil produced the greatest number of U.S. No. 1 grade of collard and kale greens compared to NM native soil. Across all treatments, concentrations of ascorbic acid and phenols were generally greater in kale than in collards. Overall, CM and SS enhanced total phenols and ascorbic acid contents of kale and collard compared to NM native soil. We investigated the chemical and physical properties of each of the three soil treatments that might explain variability among treatments and the impact of soil amendments on yield, phenols, and ascorbic acid contents of kale and collard green grown under this practice.  相似文献   
266.
文中论述了新疆地区乡镇企业发展与生态环境有关的产业结构特点和分布,分地区、分行业计算了乡镇工业1985—1988年的“三废”污染和生态破坏状况,并对1995年和2000年“三废”污染控制数量及生态—经济规划指标作了综合评述。提出了新疆乡镇企业经济与生态环境保护协调发展战略的主要对策和建议。  相似文献   
267.
针对石油天然气勘探钻井过程中存在的不合理用水问题,运用水平衡测试方法进行对比、分析,提出了节约用水措施,健全了用水管理制度,使钻井生产耗水量降低到合理值,有效地控制了废水的产生量。  相似文献   
268.
电解法处理高含硫气田水   总被引:1,自引:0,他引:1  
本文详细介绍了川南矿区含硫气田水电解法处理的试验情况,用自己研制的电解反应器对电解时间、pH值、电流密度等工艺条件进行了考察,提出了电解法处理含S~(2-)200mg/L的气田水的最佳工艺条件。试验结果表明:该方法是成功的,它可以使气田水中硫化物的脱除率达99%以上,达到国家排放标准(GB8978—88:S~(2-)<5mg/L)。该方法的主要特点是投加处理药剂少,操作简便,设备小型,占地面积小,特别适用于产水量不大的井站使用。  相似文献   
269.
ABSTRACT: Twenty-two gaging stations were selected for developing a regional flood frequency curve for small (area less than 2 square miles) watersheds in southern Illinois. Five probability functions were compared, and the extreme value type I function was selected to develop the regional flood curve. The curve was generated with the index flood method and also another empirical method that related the function parameters to the watershed area. Estimated peak discharges with various return periods were compared with the results obtained from multiple regression analysis.  相似文献   
270.
Traunsee is a deep oligotrophic lake in Austria characterised by an artificial enrichment of chloride in the hypolimnion (up to 170 mg L-1) caused by waste disposal of soda and salt industries. Protists were collected monthly over one year, observed alive and after Quantitative Protargol Staining (ciliates) or via epifluorescence microscopy (heterotrophic flagellates). Three sites within the lake (0–40 m depths) were compared to deeper water layers from 60–160 m depths where chloride concentrations and conductivity were increased. In addition, we observed the protozooplankton of two neighbouring lakes, i.e. reference systems, during one sampling occasion. In Traunsee the abundance of ciliates was low (200–36 600 cells L-1) in contrast to high species diversity (at least 60 different species; HS = 2.6) throughout the year. The main pelagic species in terms of abundance were small oligotrichs and prostomatids like Rimostrombidium brachykinetum/hyalinum, Balanion planctonicum and Urotricha spp. throughout the investigation period. Among free-living heterotrophic flagellates, which occurred at densities of 40–2800 cells mL-1, small morphotypes dominated in the pelagial. No differences at the community level between the three lakes could be observed and pelagic ciliates and flagellates seemed not to be affected by increased chloride concentrations or by enhanced conductivity.  相似文献   
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