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11.
常里温泉处于普渡河断裂与大密罗-马官屯断裂交汇带,地质构造条件特殊,地下水循环较复杂.温泉水温高、水质好、埋藏浅、易开采、交通方便等优势,具有较高的开发价值.温泉形成机理,补、径、排循环系统的研究,有助于科学、合理指导开发利用温泉资源. 相似文献
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Wave Energy Converters (WECs) have excellent potential as a source of renewable energy that is yet to be commercially realised. Recent attention has focused on the installation of Oscillating Water Column (OWC) devices as a part of harbor walls to provide advantages of cost–sharing structures and proximity of power generation facilities to existing infrastructure. In this paper, an incompressible three–dimensional CFD model is constructed to simulate a fixed Multi–Chamber OWC (MC–OWC) device. The CFD model is validated; the simulation results are found to be in good agreement with experimental results obtained from a scale physical model tested in a wave tank. The validated CFD model is then used for a benchmark study of 96 numerical tests. These investigate the effects of the PTO damping caused by the power take–off (PTO) system on device performance. The performance is assessed for a range of regular wave heights and periods. The results demonstrate that a PTO system with an intermediate damping can be used for all chambers in the MC–OWC device for most wave period ranges, except for the long wave periods. These require a higher PTO damping. An increased incident wave height reduces the device capture width ratio, but there is a noticeable improvement for long wave periods. 相似文献
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Quality Requirements for Fresh Waters: Water Quality Targets, Water Quality Objectives, and Chemical Water Quality Classification In the Federal Republic of Germany, water quality requirements for the protection of inland surface waters against hazardous substances are formulated on the basis of a quality targets derivation concept developed jointly by the Federal Government and the Federal States. The quality requirements were termed “water quality targets” in order to make it clear that the values derived are orientational values rather than legally binding limit values. The international comparison of quality requirements for surface waters shows that, on the whole, the national quality targets ensure a high level of protection. According to present scientific knowledge, impairments of uses, such as supply of drinking water, or risks to aquatic communities need not to be expected if the quality targets are complied with. A comparison of water quality data with the water quality targets makes it possible, on the one hand, to identify those substances whose inputs must be further reduced; on the other hand, it also shows that, for a number of substances, there is no need at present for concern over their adversely water quality. A further differentiation of the aquatic hazard potential of pollutants allows a water quality classification system to be developed on the basis of the quality targets derivation concept. The basic elements of this water quality classification system are presented, and its application is explained by way of examples. 相似文献
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磁铁矿采空区处理施工工艺与技术方法探讨 总被引:3,自引:0,他引:3
文章系统地介绍了采用地质钻机成孔,高压注浆机进行充填注浆的施工方法。为了将水泥砂浆及水泥粉煤灰浆填入采空区,采用能施加高压的输送泵及高压注浆设备、铸铁注浆管、水泥封孔的注浆工艺处理采空区铁路路基。在信息化施工过程中,通过试验不断地调整设计方法、改进施工工艺,在处理巨型磁铁矿采空区工程实践中达到了预期的目标。施工中,在控制充填边界、封孔方法及施工工艺等方面有一定的创新。提出的采空区施工技术控制、质量检测与评价方法,对同类工程勘察、设计及施工具有一定的参考价值。 相似文献
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Tidal mixing plays an important role in the modification of dense water masses around the Antarctic continent. In addition to the vertical (diapycnal) mixing in the near-bottom layers, lateral mixing can also be of relevance in some areas. A numerical tide simulation shows that lateral tidal mixing is not uniformly distributed along the shelf break. In particular, strong mixing occurs all along the Ross Sea and Southern Weddell Sea shelf breaks, while other regions (e.g., the western Weddell Sea) are relatively quiet. The latter regions correspond surprisingly well to areas where indications for cross-shelf exchange of dense water masses have been found. The results suggest that lateral tidal mixing may account for the relatively small contribution of Ross Sea dense water masses to Antarctic Bottom Water. 相似文献
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《Geoforum》2015
This paper examines the importance of national-level institutional arrangements for promoting the EU’s Protected Geographic Indication scheme (PGI). Taking the example of Ireland, for which PGI designations remain comparatively low, it explores whether the approach to providing institutional supports to the PGI scheme is influenced by top-down technocratic governance structures that pertain to food safety and quality certification that encompass the broader operating environment for food production in Ireland. Although the regulation of food safety and quality certification are distinct remits to the administration of the PGI scheme, in the Irish context the same institutional bodies are involved in governance of both. Using a discourse analysis interpretative framework, this paper draws on interviews with Irish producer group members and institutional representatives to examine how governance of the PGI scheme reflects management perspectives and practices more in keeping with a regulatory environment for food safety and quality than with development of place-based food product links. It suggests that incentives to avail of the PGI scheme as a means of realising value-added for producers are not well established because they require the development of more subjective, context-dependent processes and practices linked to geographical place and place identity. These are not easily accommodated under current institutional arrangements that also incorporate food safety and quality remits because these are in turn strongly established through nationally and internationally recognised systems of regulation and benchmarking. The findings point to the benefits to be gained from a more layered governance structure for PGI; devolving operation of the scheme to relevant regional and local development organisations that possess the expertise and relevant local knowledge to (a) incentivise the formation of producer groups, and (b) prioritise mentoring and support for PGI concept development as a clearer reflection of bottom-up rural sustainability policy. 相似文献
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Analysis of monthly mean river temperatures, recorded on an hourly basis in the middle reaches of the Loire since 1976, allows reconstruction by multiple linear regression of the annual, spring and summer water temperatures from equivalent information on air temperatures and river discharge. Since 1881, the average annual and summer temperatures of the Loire have risen by approximately 0.8?°C, this increase accelerating since the late 1980s due to the rise in air temperature and also to lower discharge rates. In addition, the thermal regime in the Orleans to Blois reach is considerably affected by the inflow of groundwater from the Calcaires de Beauce aquifer, as shown by the summer energy balance. To cite this article: F. Moatar, J. Gailhard, C. R. Geoscience 338 (2006). 相似文献
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