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991.
F. A. Nicholson BSc MSc PhD B. J. Chambers BSc PhD A. Moore BSc PhD R. J. Nicholson BSc G. Hickman BSc 《Water and Environment Journal》2004,18(3):155-160
A review was undertaken of (a) the levels and prevalence of Salmonella spp., Campylobacter spp., Listeria monocytogenes, Escherichia coli 0157. Cryptosporidium parvum and Giardia intestinalis in livestock manure, and (b) factors which affect their survival during storage and following land application. Pathogens are commonly present in livestock manures and can survive in soil for several months or years after spreading or excretion onto land. Temperature was identified as being the most important factor influencing pathogen survival, although pH, UV light and drying were also important. Various practical measures to minimise the risk of pathogen transfer into the food chain were identified, including treatment, extended storage and no/harvest periods following land spreading. Guidelines are being developed on managing farm manures to minimise the risks of microbiological contamination of ready-to-eat crops. 相似文献
992.
二次供水技术及方案比选 总被引:1,自引:0,他引:1
从能耗、供水安全、水质保障以及投资和运行费用等方面对常用二次供水方式进行了技术经济分析,论述了高层供水的压力分区以及低位蓄水池、高位蓄水池、中间水箱设置的优缺点,推荐采用市政供水管网→工频泵→高位水箱→用户的二次供水方式. 相似文献
993.
In the air conditioning (AC) industry chilled water storage (CWS) systems are one form of cool thermal storage technology that can be used to time shift the electrical load of the system from the peak day periods to off peak night time periods. In this paper the data for the actual exported and generated electrical energy obtained for the power stations in Kuwait has been used to estimate the electrical energy consumption and the peak electrical load of AC systems. Since the chiller in an air cooled AC system represent more than 75% of the total electrical power consumed by an AC system during the peak demand period, the impact of using CWS systems with alternative operating strategies including partial (load levelling), partial (demand limiting) and full load has been investigated. In our conclusions we estimate that approximately 45% of the total annual exported electrical energy is consumed solely by AC systems as a result of the very high ambient temperatures occurring between March and October. Furthermore, it is estimated AC systems represent about 62% of the peak electrical load. The results demonstrate that CWS can reduce the peak electrical load of a chiller in an air cooled AC system by up to 100% and reduce the nominal chiller size by up to 33% depending upon the operating strategy adopted. This is achieved with only a 4% increase in power consumption of the chiller for all CWS strategies except for full storage where the energy consumption actually decreases by approximately 4%. 相似文献
994.
锋尚国际公寓工程按照欧洲高舒适度低能耗优化设计理论对建筑的采暖制冷、外墙外保温、屋面保温、外窗、室内新风和垃圾处理等进行了全面系统的环保优化设计,在施工中研究应用了由天棚低温辐射采暖制冷系统核心施工技术与干挂饰面砖幕墙聚苯复合外墙外保温主要配套施工技术,以及置换式健康新风系统、低辐射保温密闭外窗系统、中央吸尘系统、防噪声系统、水处理系统等多项系统技术。其技术特点是舒适、健康、节能、环保、经济和美化城市环境。 相似文献
995.
浅谈低温热水地板辐射采暖 总被引:1,自引:4,他引:1
介绍了低温热水地板辐射采暖的特点,对低温热水地板辐射采暖的设计及施工要点进行了阐述,提出了低温热水地板辐射采暖的精品策划。 相似文献
996.
德国新型建筑节能理念与应用 总被引:7,自引:1,他引:7
介绍了德国当前的建筑节能理念和实际技术的应用,并针对中国目前情况提出建筑生态节能设计系统的概念及其重要组成部分;建筑整体的能量平衡系统设计;优秀的建筑构造系统设计和正确地选用建筑材料和技术设备系统。 相似文献
997.
在环境问题日益凸现的今天,太阳能作为一种可再生的清洁能源被人们誉为21世纪最有希望的能源.当前太阳能最具潜力的发展领域就是在建筑中的利用.现代城市建筑中太阳能技术的应用已经成为建筑节能领域的技术热点.针对我国目前太阳能在建筑上的利用现状,分析了建筑一体化的太阳能热水系统和太阳能光伏系统. 相似文献
998.
This study presents the relationship between the dam hydrology and phytoplankton proliferations in a regulated river system in East Asia. A long-term ecological study reveals that multi-purpose dam regulation on river flow in the Nakdong River (South Korea) affects proliferating patterns of phytoplankton, especially during summer (June-August) and winter (December-next February) as Microcystis aeruginosa and Stephanodiscus hantzschii, respectively, dominate each season by over 80%. Eutrophication was observed in the lower Nakdong River (South Korea) (mean+/-standard deviation: nitrate-N, 2.8+/-0.9 mg L(-1); phosphate-P, 40.3+/-31.3 microg L(-1); chlorophyll a, 45.2+/-84.9 microg L(-1); n=449), and the limnological characteristics responded to climatic variations such as monsoon and summer typhoons. The river basin experiences concentrated rainfall during the rainy season (June-September, over ca. 60% of total annual rainfall). Correlation and cross-correlation for time-delayed relationship revealed the hydrological environments (i.e., quantity of dam storage and discharge) had significantly negative relationship with the population dynamics of the two bloom-forming species for up to the next 2 years. S. hantzschii had clearer relationship with dam storage and discharge, which might be due to the seasonality exhibited by the species. The results support the necessity of "smart flow control" which may enable destruction of bloom formation by the two species with an adequate pulse of discharge generated by upstream dams in the far-east Asian river systems. This would increase the efficiency of water resource management system. 相似文献
999.
针对《公共建筑节能设计标准》中对建筑热工设计的规定,结合工程实际,计算分析了办公建筑节能设计的影响因素,供设计参考。 相似文献
1000.