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21.
The fens of eastern England rely on flood defences for their existence, and planning for flood risk has always had a high priority. A new focus was given with the issue of Planning Policy Guidance 25, and this paper presents experience from a Strategic Flood Risk Assessment of South Holland District, in Lincolnshire. The assessment pioneered the examination of fenland flood risk in terms of risk zones related to flood hazard and standard of protection. Methods for evaluating the risk zones are described; they consider flooding from embanked rivers which are subject to tide locking, internal drainage systems, tide level and wave action. The methods would be appropriate for many lowland areas of the UK where conventional flood analysis cannot be used.  相似文献   
22.
刘思跃 《中国园林》2004,20(7):25-28
根据本次规划的指导思想和基本理念,对规划区进行了植物园体系规划和园区景观规划,以实现科研、科普、生产、景观四位-体共同发展模式,并对本次规划的预期效果进行了分析和评价.  相似文献   
23.
The implementation of concepts of multiple land use seems to be relevant in the context of large-scale urban projects, which are now predominately monofunctional. However, current governance settings at these projects seem to be unreceptive to this new planning concept. Our in-depth case study of the South Axis project in Amsterdam embraces an actor-centred institutional perspective and seeks to understand how more receptive conditions for norm alignment between key actors can be attained. We reconstruct the introduction of quite radical concepts of multiple land use in this project, which started as an office-development proposal. The implementation was severely hampered by the fact that ambitions were formed in a rather introvert local government – business setting. Only in the last stage, with the adoption of a more extrovert mode of governance that included a variety of national government departments, were more receptive conditions for multiple land use created.  相似文献   
24.
始于1970年的韩国“新农村运动”,通过一系列实实在在的项目开发和建设工程,在增加农民收入、改善农村面貌、缩小城乡工农差距等方面作了探索并取得成功。虽然韩国新农村运动的发展背景、发展模式与当前上海新农村建设有一定的差别,但是其在城镇规划体系、建管机制、综合交通管理等方面依然对上海的新农村建设有一定的指导作用。  相似文献   
25.
Characteristics of airborne bacteria and fungi were surveyed in the public buildings regulated in Korea, with the six-stage cascade impactor. The total concentrations of airborne bacteria and fungi were averaged to 404 and 382 cfu m−3 in hospital, 931 and 536 cfu m−3 in kindergarten, 294 and 334 cfu m−3 in elderly welfare facility, and 586 and 371 cfu m−3 in postpartum nurse center. Mean respirable concentrations of airborne bacteria and fungi were 194 and 292 cfu m−3 in hospital, 358 and 347 cfu m−3 in kindergarten, 134 and 266 cfu m−3 in elderly welfare facility, and 254 and 289 cfu m−3 in postpartum nurse center, respectively. Based on this results, total and respirable concentrations of airborne bacteria and fungi were significantly highest in kindergarten and lowest in elderly welfare facility (p<0.05p<0.05). The ratios of indoor and outdoor concentration for airborne bacteria and fungi were below 1.0 in all the investigated public buildings regardless of size distribution. The dominant genera identified in the public buildings were Staphylococcus spp., Micrococcus spp., Corynebacterium spp., and Bacillus spp., for airborne bacteria and Penicillium spp., Cladosporium spp., and Aspergillus spp., for airborne fungi, respectively. Size distributions of airborne bacteria and fungi in terms of the dominant genera were not observed consistently except for Staphylococcus spp., which was detected mainly on the first stage (>7.0 μm) and second stage(4.7–7.0 μm), and Penicillium spp., and Cladosporium spp., showing the highest collection rate at stage 3 (3.3–4.7 μm) regardless of the kind of the public buildings.  相似文献   
26.
Elevated concentrations of reactive nitrogen (N) in precipitation have been reported for many cities in China. Due to increased use of fossil fuels and expansion in agriculture, further increases in deposition of ammonia (NHx) and reactive N oxides (NOy) are predicted. Increased deposition of reactive N is likely to affect N dynamics and N runoff in forest ecosystems. Yet, in China little work has been done to quantify the levels of atmospheric N deposition in such systems. Here, we assess the deposition of inorganic N (ammonium, NH4+ and nitrate, NO3-) for five subtropical forest ecosystems in remote and urban areas of South China. Annual volume-weighted concentrations in bulk precipitation range from 0.18 to 1.55 mg NH4+ -N L(-1) and from 0.12 to 0.74 mg NO3- -N L(-1). These values are large and several times greater than those reported for remote sites of the world. The fluxes of total inorganic N (TIN) in wet-only deposition range from 0.8 to 2.3 g N m(-2) yr(-1), with NH4+ -N contributing 54% to 77%. Both the tree canopy and the ground vegetation layer are important in determining the net N flux reaching the forest floor, but the net effect varies from site to site. At TieShanPing (TSP), close to Chongqing city, and at CaiJiaTang (CJT), near Shaoshan (Hunan province), the canopy represents a net source of N, probably due to dry deposition. At the other three sites (LiuChongGuan (LCG), LeiGongShan (LGS), both in Guizhou province, and LiuXiHe (LXH) in Guangdong), a net loss of reactive N from precipitation water occurs in the canopy, probably due to uptake processes. The total annual atmospheric TIN load is estimated to range from at least 0.8 g N m(-2) yr(-1) to 4.0 g N m(-2) yr(-1), with a considerable contribution from dry deposition. Concentrations and fluxes of inorganic N in tree canopy throughfall are greater than those in North America. Also the contribution of NH4+ -N to TIN fluxes in throughfall (40% to 70%) is greater than in North America. Our sites have N deposition levels and NH4+ -N contributions similar to those found in Northwest and central Europe. The TIN loads at TSP and CJT far exceed 2.5 g N m(-2) yr(-1), which is the N deposition load above which NO3- leaching is expected in temperate and boreal forests.  相似文献   
27.
南非是我国的重要矿业合作伙伴之一,其矿业技术发展演变过程和现行鼓励矿业技术研究的政策和计划对于我国矿业主管部门、研究教育机构和企业有一定的参考价值。本文结合矿业技术专利和矿山机械进出口数据对南非矿业技术的发展历史和现状进行了分析,调研了南非矿业研发活动的主要参与者、与矿业研究有关的主要政策、计划和项目,提出了借南非矿业景气下滑之机,利用中南政府间科技合作项目、金砖国家新开发银行等平台和渠道,加强中南矿业技术合作、吸纳南非优秀人才的建议。  相似文献   
28.
南美Llanos盆地中部地区为盆地内的重要产油区,对其烃源岩及原油的地球化学特征分析,能揭示出盆地内的排烃和运聚过程及原油的生物降解特征。通过岩石热解、原油组分分析等方法和手段,结合多种生标参数,对这一地区的烃源岩及原油的地球化学特征进行了系统和全面的分析,结果表明:Gacheta组烃源岩沉积在较少的陆源有机质、咸水和弱氧化—弱还原环境,为腐泥—腐殖混合型干酪根;Los Cuervos组烃源岩沉积在较多的陆源有机质、半咸水和氧化环境,为腐泥—腐殖混合型和腐殖型干酪根,2套烃源岩都处于低—中等的成熟程度,均具有较强的生烃潜力;盆地中部地区存在A、B、C三类原油,其中A类为白垩系烃源岩油;B类为古近系烃源岩油;C类系前两者的混合;在大部分的油样中含有丰富的重排甾烷,二苯并噻吩/菲含量低,而Pr/Ph值较高,这说明原油对应的烃源岩为海相页岩而非碳酸盐岩;原油组分受生物降解及二次充注过程的控制,从Santiago油田沿北东方向到La Gloria等油田生物降解作用呈减弱的趋势,而Cupiagua和Buenos Aires油田的样品受二次充注的轻质油的影响,其API远远超过La Gloria等油田。  相似文献   
29.
南苏丹Melut裂谷盆地扇体的发现及油气意义   总被引:1,自引:0,他引:1  
Melut盆地为中非剪切带走滑背景下形成的裂谷盆地,具有早期白垩世被动裂谷盆地和晚期古近纪—新近纪主动裂谷盆地相叠合的特征,长期以来一直围绕辫状河、三角洲等领域进行勘探。通过地质—地球物理综合研究,在盆地北部凹陷识别出一系列扇体沉积,包括凹陷东部Abyat扇三角洲、西部Ruman近岸水下扇等。这些扇体主要形成于盆地初始被动裂谷期,发育于下白垩统Al Renk组烃源岩及烃源岩附近的白垩系Galhak组和Al Gayger组内,具有良好的生、储、盖配置条件。扇体的发现证实了Melut等中非裂谷盆地的初始被动裂谷期同样发育类似于主动裂谷盆地的扇三角洲、水下扇等各种扇体沉积,且具有良好的成藏条件和勘探潜力,这一发现和认识拓展了中非裂谷盆地的勘探潜力和空间。  相似文献   
30.
南海东部某油田隔水导管腐蚀失效分析   总被引:1,自引:0,他引:1  
目的 分析南海东部某油田隔水导管腐蚀失效行为,便于确定该海上油田隔水导管腐蚀类型,分析其腐蚀特点,指导其防腐处理,从而改善海上油井生产现状,延长油井生产年限,提高油井产能。方法 基于废弃隔水导管宏观分析的初步判断,对隔水导管的材质、腐蚀形貌、腐蚀程度与产物成分进行分析。 结果 该海上油田隔水导管力学性能、化学成分及金相组织均符合API Spec 5L标准。SEM及体式照片显示,外壁比内壁腐蚀更严重。内壁发生了轻微腐蚀,以均匀腐蚀为主;外壁发生了局部腐蚀,点蚀坑深度在115 μm左右,且出现了微裂纹,裂纹宽度在150 μm左右,表明X56隔水导管具有一定的SCC倾向。EDS分析显示腐蚀产物主要元素为Fe和O,二者质量总和超过75%。XRD分析确定腐蚀产物的主要成分为γ-FeO(OH)。对比防腐涂装和未涂装挂片腐蚀形貌,合金和有机防腐涂层具有良好的防腐蚀效果,可有效地隔绝腐蚀介质与金属本体的接触,阻止腐蚀反应发生。结论 海上油田隔水导管的腐蚀过程以吸氧腐蚀为主。内壁以均匀腐蚀为主,腐蚀较轻微;外壁发生了局部腐蚀,且出现了微裂纹。合金和有机防腐涂层具有良好的防腐蚀效果,可推广至现场,有效延长油井生产年限。  相似文献   
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