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1.
The literature on urban farming in Sub-Saharan African cities reveals that most studies have been conducted in Eastern, Southern and Central African cities. A few have focused on West Africa, including Sierra Leone, Guinea Bissau, and Cameroon. In Ghana there is a paucity of information on urban farming. The purpose of this paper is to examine the status of urban cultivation in Accra, Ghana's capital, reviewing existing research, and to present new empirical findings on urban cultivation emphasizing on its history, nature, practices, problems, potentials and urban planning implications. 相似文献
2.
粉煤灰在废水处理中的应用 总被引:7,自引:0,他引:7
介绍了粉煤灰的结构及物理化学特性,处理废水的机理,综述了国内外利用粉煤灰处理各种废水的最新研究成果。目前利用粉煤灰处理废水主要应用于城市污水、印染废水、造纸废水、制药废水、电废水、重金属废水及含酚、含氟废水的处理。同时介绍了几种粉煤灰改性的方法及应用前景。 相似文献
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Liberia has gone through civil crisis for over a decade which has resulted in the destruction of infrastructure and disruption of basic services delivery particularly in Monrovia, the capital city. Most of the 1.3 million people living in Monrovia are without adequate environmental sanitation and waste management services which situation poses a serious health risk to the residents. The current waste management service coverage is less than 20% and disposal is by indiscriminate open dumping. In 2003, there were series of outbreaks of cholera epidemics in the city during which time a total of 26,651 cases were reported with many dying.The waste management plan was initiated as an exit strategy of UNICEF following an intervention response programme to assist the Monrovia City Corporation (MCC) whose capacity in this area had been crippled as a result of years of war, through the provision of support in solid waste collection and disposal.The objectives of the plan were to:
- (a) Improve waste management services delivery in the city.
- (b) Strengthen the ability of the MCC to plan and manage the waste services delivery.
- (c) Enhance cooperation of service beneficiaries through comprehensive and effective health education and service promotional campaign.
- (d) Enhance revenue generation and community participation through the promotion of private sector and CBOs/NGOs active involvement in the waste management service delivery.
5.
通过对两组汉字的研究,发现汉字的结构中存在一个核心———字核,它具有简化汉字结构、沟通若干汉字的桥梁作用。据此,笔者提出在汉字的结构中普遍存在字核的假设,再依此假设对《辞海》的全部汉字(14872个)进行了系统研究。研究发现其中的14582个汉字的结构中存在字核,占被研究汉字总数的98%以上。全部汉字中共有字核900余个,列于字核总表中。结果表明:字核在汉字结构中客观而普遍的存在,它具有简化汉字结构、沟通同一字核的若干汉字联系的桥梁作用。 相似文献
6.
本文总结了高能核—核碰撞的多源模型自1987年提出到1990年以来的主要进展,着重介绍多源模型的基本物理思想及其在两种不同方案下的发展动态.通过与最新实验数据比较,说明多源模型能够成功地解释高能重离子碰撞的整体性质. 相似文献
7.
This paper presents two case studies on the efforts by a community-based organisation to promote a sustainable integrated waste management system in Indian mega cities. This effort was initiated in 1989 by a local non-governmental organisation (NGO) called EXNORA and is based on a ‘zero waste management scheme’ set up, run and financed by the residents themselves. As this model has been widely quoted as successful, the study aims at learning from two communities implementing this model.Results are reported from a survey of the two schemes that used various tools to assess both their performance and sustainability in selected residential areas of two Indian cities, Chennai and Hyderabad. The results indicate limited success of the schemes both in saving a significant fraction of the generated waste from dumping, and in rehabilitating the local poor. However, they show that motivated individuals can successfully set up and manage waste collection systems that lead to overall environmental improvements. The differences in the two schemes reflect how the local assets and contexts impact on the success of the scheme. The scheme in a rich neighbourhood of Hyderabad was less ambitious in its overall objectives and focussed on the provision of a waste management service, using the opportunity to provide local employment to a socially deprived fraction of the population. The scheme in a middle-class area of Chennai, although pioneering in its approach, suffered from diseconomies of scale and lack of social integration, making it less viable in the medium to long term. Both schemes suffered from a lack of community involvement, motivation and political support, which threatens the long-term sustainability of the enterprise. The research concludes that the role that communities can realistically play in management of their own waste depends on the local context. The system advocated by EXNORA seems to require significant local resources, and political and technical support which are hard to find and sustain without strong local leaders. Another model set up in the city of Visakhapatnam is finally introduced as an alternative. This is based on triangular contracts between the municipality, the residents and micro-enterprises and may provide a good solution in dealing with the technical and commercial aspects which communities find difficult. 相似文献
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论现代企业品牌管理 总被引:1,自引:0,他引:1
赵凤兰 《河南教育学院学报(哲学社会科学版)》2002,21(3):87-90
美国经济的衰退和全球高新技术市场的增长滞缓 ,给寻求跨地域发展的企业投下了重重的阴影 ,以往成功的经验已不足以借鉴。中国企业目前所具有的竞争力只能保持 3- 5年的时间。加入WTO后 ,中国企业品牌的寿命周期将会大大缩短。面对国际、国内环境的巨大变化 ,企业品牌的核心竞争力必须进行重新评价和创意。 相似文献
10.
通过对上海市杨树浦废水站工业废水的混凝沉淀实验研究,确定了废水混凝沉淀最适宜的混凝剂种类、最佳的混凝反应条件及最优的药剂投加量,这不仅能节省药剂、降低工程运行费用,而且还能在很大程度上提高水的混凝沉淀处理效果。 相似文献