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51.
引江济太工程的实施使太湖流域望虞河西岸的水环境问题更加凸现,引水期间大量污水没有出路,造成局部地区水环境恶化;污水的汇入使得引江济太工程不能充分发挥作用。从区域控制的角度,以常熟市望虞河西岸地区为例,建立研究区域的感潮河网水量水质模型,提出相应的排水出路,对研究区域的截污方案进行研究。 相似文献
52.
横跨非洲大陆中部巨型中非断裂带东端的穆格莱德盆地的演化与周邻的大地构造背景密切相关。在早白垩世的演化与大西洋的分阶段张裂密切相关,晚白垩世的演化与印度块体的快速北移有关,新生代的演化主要和红海的扩张有关。盆地的构造演化可划分三大阶段:在早白垩世盆地发育的鼎盛时期,受中非走滑断裂的影响,盆地沉降速率巨大,沉积中心和沉降中心往往不一致;在晚白垩世,盆地为断陷和坳陷型沉积,沉积中心向远离中非断裂带的东南方向迁移。盆地总体的演化具有从走滑型向拉张伸展型转化的特点。在盆地演化的早期,烃源岩和储集岩在靠近中非走滑断裂带附近较发育;在晚期的构造挤压作用下,一方面对已形成的油气藏进行破坏,同时,可造成油气重新分布,形成一些新生的油气藏。在该部位沉降中心和沉积中心往往不一致,这给油气的勘探带来新的困难,因此对这些地区的勘探要十分慎重。在远离中非断裂带的盆地东南部,是晚期沉积和沉降的中心,主力烃源岩演化比较适中,油气成藏期较晚,是寻找具有工业价值油气田的有利部位。 相似文献
53.
Planning in Sub-Saharan Africa owes much to the colonial legacies that inform the shape and composition of African urban spaces and places. This applies to legislation, institutional systems and planning education. In 2008, the Association of African Planning Schools AAPSs embarked on a 3-year initiative on the revitalisation of planning education in Africa, funded by the Rockefeller Foundation. The aim of the project was to propose ways through which the training of urban planners can be more responsive to the special circumstances of African urbanisation. This paper reflects on this initiative. 相似文献
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Daodi Flood Land, located in Mentougou District of Beijing, is a relatively separate flood land in the lower reaches and on the east of Yonding River. This largest landscape character area in the west of Beijing along the river illustrates the history of human–water interaction and discloses the trends and problems of rural urbanization. Focusing on Daodi Flood Land, this paper expands the research on adaptation by introducing basic concepts and research framework, and reviews the research trends from spatial, temporal, and participant aspects. Considering the typical characters of the study area, this research employed participatory approaches, such as mapping and problem and solution trees, due to the lack of continuous and accurate data. Basing on literature review and field investigation on issues of floods, agricultural irrigation, and water resource utilization, water adaptive development visions for the study area were proposed from perspectives of landscape and culture. Finally, the paper further analyzes the structural relations between adaptation problems, natural and social systems, passive and active adaptations, and planned and unplanned adaptations, with the aim to provide reference for relevant studies and applications of adaptation approaches in other cases. 相似文献
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Dongdong Feng Dawei Guo Yijun Zhao Heping Tan Guozhang Chang Tianpeng Zhang Shaozeng Sun 《能源学会志》2019,92(6):1670-1682
Oxygen-fuel combustion is a promising technology for CO2 emission reduction. The high-temperature entrained flow reactor and high-temperature drop tube furnace were used to analyses the formation and O2/CO2 combustion characteristics of real-environment coal char in high-temperature oxy-fuel conditions. It proposed “inflection point standard” of high-temperature flame method for the preparation of real-environmental oxy-fuel coal char according to the flame method. The results show that the ratios of C=O/C-O and C=O/Car increase in the coal char compared with the raw coals. The trend of C=O/Car in oxy-fuel condition is opposite to that in the inert atmosphere, due to the effect of high-concentration CO2. To achieve the burnout rate similar to air combustion for coal char, with the increase of coal rank, the O2 concentration should be enhanced. The optimal O2 concentration for the oxy-fuel combustion of JC anthracite is 30%, while that of other low-rank coals could be lower than 30%. The combustion characteristic of JC anthracite is with the highest sensitivity to temperature and O2 concentration. 相似文献
59.
《Cities》2014
Berlin is a German city and federal state, situated in the heart of Europe. It has been the capital city since 1991, and is the largest city in the country with around 3.4 million inhabitants. This profile explains Berlin’s historical development and emphasizes changes which took place during the 20th century (the Weimar period in the 1920s, followed by the Nazi takeover in 1933 and the city’s destruction during World War II, then the division of the city into West Berlin and East Berlin, until its final reunification in 1990 after the Wall fell down). After reunification, Berlin experienced a new period of urban redevelopment in which many new buildings were constructed. This profile also outlines some recent positive changes in terms of Berlin’s economic growth and its transformation into the capital of innovative new companies in the digital, culture and media industries. 相似文献
60.
Felicity D Scott 《Architectural Design》2015,85(3):78-85
Felicity D Scott , Associate Professor of Architecture at Columbia University Graduate School of Architecture, Planning and Preservation (GSAPP), describes here the instant city events of the early 1970s. These foreshadowed current global village media practices in what now seems a quaintly material manner: communication between sites involved the physical mailing of videotapes and ‘wire photos’ through the postal service. The sites themselves – in the US and elsewhere – were transformed into ‘instant cities’ through the erection of physical geodesic domes, teepees and inflatables in seas of mud. The true antecedents of today's instant networking, these pioneers embraced the newest technology available at the time and the most innovative forms of temporary architecture. 相似文献