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101.
102.
介绍了家用空气源热泵热水器的工作流程,研究了目前国内市场上3种家用空气源热泵热水器——户内整体机、户内分体机、户外分体机的结构。分析了空气源热泵热水器的设计要点。 相似文献
103.
A/O—MBR处理低浓度生活污水的试验研究 总被引:1,自引:0,他引:1
针对传统活性污泥法处理低浓度生活污水难度大的问题,采用缺氧-好氧膜生物反应器(A/O—MBR)处理该类污水,并考察了其处理效果。结果表明,在污泥浓度为4000~6000mg/L、HRT为19.2h、好氧段溶解氧浓度为1.5~2.5mg/L、污泥回流比为200%~300%的条件下,A/O—MBR对COD和氨氮的去除效果良好,平均去除率分别为92.2%和95.9%。在无排泥的情况下,系统连续运行近100d,出水水质稳定。 相似文献
104.
W. J. LEWIS BSc MSc CChem MRSC P. J. CHILTON BSc MSc MIGeol 《Water and Environment Journal》1989,3(1):82-88
I ron is not normally considered to be a constituent of health significance, and recommended limits for iron in drinking water supplies are based on aesthetic considerations. Experience in Malawi has demonstrated that, even when present in only trace amounts, iron can influence the consumer's acceptance of an improved borehole supply. The effect of the use of plastic construction materials on the iron content of village groundwater supplies was investigated using a statistical approach. The majority of groundwater points using only plastic materials was found to supply water containing less than the WHO guideline value of 0.3 mg/l iron. In contrast, the use of ferrous-materials increased the iron content of the water to unacceptable levels, sometimes causing the consumers to reject the borehole as a source of drinking water.
Bacteriological data show that the quality of the alternative, traditional supply is far inferior to the new improved supply. An otherwise perfectly safe supply may therefore be abandoned as a direct result of contamination introduced by 'down the hole' components. This frustrates efforts to improve the well-being of rural communities, and is a waste of precious development resources. 相似文献
Bacteriological data show that the quality of the alternative, traditional supply is far inferior to the new improved supply. An otherwise perfectly safe supply may therefore be abandoned as a direct result of contamination introduced by 'down the hole' components. This frustrates efforts to improve the well-being of rural communities, and is a waste of precious development resources. 相似文献
105.
106.
The EC Directive (91/271/EEC) concerning urban waste water treatment has far-reaching financial and technological implications for local authorities in Scotland which are responsible for sewerage. Increased capital consent limits and additional financial assistance from central government are essential if the requirements of the legislation are to be met.
Although the Directive is welcomed in general terms, the sections of the legislation dealing with the identification of sensitive waters and the provision of primary treatment for coastal discharges to less sensitive waters are of limited environmental significance in Scotland.
The elimination of sewage sludge disposal at sea will create severe difficulties for Scottish authorities as a high percentage of sewage sludge is currently disposed of at sea. Each of the main alternative disposal options presents environmental, financial and technical problems and, in the case of incineration, the certainty of widespread unpopularity with the public. 相似文献
Although the Directive is welcomed in general terms, the sections of the legislation dealing with the identification of sensitive waters and the provision of primary treatment for coastal discharges to less sensitive waters are of limited environmental significance in Scotland.
The elimination of sewage sludge disposal at sea will create severe difficulties for Scottish authorities as a high percentage of sewage sludge is currently disposed of at sea. Each of the main alternative disposal options presents environmental, financial and technical problems and, in the case of incineration, the certainty of widespread unpopularity with the public. 相似文献
107.
Fuzzy综合评价在选择最优设计方案中的应用 总被引:1,自引:2,他引:1
应用Fuzzy数学方法建立住宅建筑设计方案的综合评价系统,运用层次分析法(AHP)确定指标权重,建立Fuzzy综合评价的多级模型,并在二级综合评判时引入一种新的评价方法,从而使Fuzzy综合评价更具客观性。 相似文献
108.
109.
110.
结合对中小城市一些农村住宅的调查研究,介绍了农村住宅的建设特点及结构特点,分析了农村住宅质量存在的问题及原因,介绍了一系列提高农村住宅建设质量的措施,以促进农村住宅建设的飞速发展。 相似文献