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181.
182.
Abstract Having argued the importance of China's sustainable development in global sustainability, the authors review the achievements of China in sustainable development, especially its institutional construction. Environment to be counted in official's political performance rating system is thought of as a new institutional mechanism in China facilitating its sustainable development and then global sustainability. Then its significance is narrated and visions in future are envisioned. In the end, certain concrete suggestions for the rating system are given in a practical way. 相似文献
183.
《International Journal of Green Energy》2013,10(3):313-325
Abstract This article summarizes the results of a study for a 100 kWe DC electrical power PEM fuel cell system. The system consists of a pre-steam reformer, a steam reformer, high and low temperature shift reactors, a preferential oxidation reactor, a PEM fuel cell, a combustor, and an expander. Acceptable net electrical efficiency levels can be achieved via intensive heat integration within the PEM fuel cell system. The calculations take into account the auxiliary equipment such as pumps, com pressors, heaters, coolers, heat exchangers and pipes. The process simulation package “Aspen-HYSYS 3.1’’ has been used. The operation parameters of the reactors have been determined considering all the technical limitations involved. A gasoline type hydrocarbon fuel has been studied as hydrogen rich gas source. Thermal efficiencies have been calculated for all of the major system components for selected operation conditions. The fuel cell stack efficiency has been calculated as a function of cell numbers (500, 750, 1000, and 1250 cells). Efficiencies of all of the major system components along with auxiliary unit efficiencies determine the net electrical efficiency of the PEM fuel cell system. The obtained net electrical efficiency levels are between 34 (500 cells) to 41% (1250 cells). 相似文献
184.
Sediment samples were collected between 1996 and 1998 during 4 cruises in the northern sector of the Adriatic Sea, facing the Po River outflow. In each sampling period, after identification of the front line, a grid of 6 sampling stations was selected in order to cover: the coastal area (largely affected by river waters), the inner and outer front areas, and the offshore waters. The biochemical composition of sedimentary organic matter (OM, lipids, proteins, carbohydrates and photosynthetic pigments) and enzymatic activity rates were studied to provide information on the potential organic matter turnover. Tentative estimates of the organic carbon budgets (input/production versus requirement by benthic consumers) are presented. Benthic carbon requirements, estimated from bacterial plus meiofaunal secondary production, was high (897 r mg r C r m m 2 r d m 1 ). OM concentrations in the Northern and Middle Adriatic Sea displayed high values, proteins being dominant, thus suggesting inputs of freshly produced material to the sea floor. OM turnover was generally rapid (11-30 r d m 1 ) and higher during summer. The uncoupled enzymatic rates ( i.e. faster protein than carbohydrate mobilisation in February, 1997) determined a decrease of the OM quality that plays an important role in biogeochemical cycles and OM diagenesis, limiting bacterial secondary production and sedimentary organic carbon utilisation. These data suggest that the efficiency of the system in the transfer of energy through the food web is generally higher in summer, especially during mucilage production. 相似文献
185.
Contaminated stormwater runoff from oil and gas (O&G) operations can pose a significant threat to surface waters. The purpose of this study is to examine the extent of this threat and identify more specific permitting requirements to protect surface waters. To better understand the extent of the threat, this paper identified and characterized the use of waste surface impoundments at O&G facilities as well as the threat level from O&G spills in California. To assess the efficacy of the current federal and California state-permitting regime, the paper evaluated stormwater permit compliance in two California counties. It also reviewed selected spill cases and associated Spill Prevention, Control and Countermeasure Plans and Stormwater Pollution Prevention Plans to identify the adequacy of current industry practices.The analysis showed that contaminated stormwater from O&G facilities can be better regulated. The U.S. Environmental Protection Agency does not require O&G facilities to file for an Industrial Stormwater General Permit even though many O&G industry practices have the potential to contaminate stormwater runoff from the site. When O&G facilities discharge a Reportable Quantity of a hazardous chemical or violate a water quality standard, they are required to enroll in the National Pollutant Discharge Elimination System permit program. Spills, although not a direct indication of stormwater runoff, can highlight polluted runoff discharges that should have been regulated. Medium and large spills that reached waterways were such a risk for which operators did not file for a permit. In California new filing requirements for the oil and gas industry require all facilities that discharge stormwater that has come into contact with any overburden, raw material, or intermediate products located on the site, to file for an Industrial Stormwater General Permit. As this study showed, there has been an increase in enrollment since the enactment of the new requirements. Having all facilities enroll in the general permit program, as done in California, would require minimum monitoring and maintenance that could help prevent spills. A further step to ensure better protocol is to require specific pollution control practices in addition to the current general permit requirements. Such permitting regimes not only can be implemented on the US federal level but also internationally. 相似文献
186.
环境风险预警方法与应急成套装备的应用展望 总被引:1,自引:0,他引:1
介绍了环境风险预警方法建立的环境风险预警指标体系、环境风险源管理平台、环境风险源风险评估技术方法以及模块式应急成套装备的技术特点等;分析了环境风险预警方法与应急成套设备在危险化学品环境风险与应急管理,在区域大气环境挥发性有机污染物(VOCs)监控预警等方面的实际需求。面临现实的环境风险状况从环境风险防控与应急工程技术研究中心建设角度提出了需进一步完善、开发的环境风险预测预警技术与应急成套装备等新思路。 相似文献
187.
阐述了劳动安全卫生标准体系研究的目的与意义,分析比较了劳动安全卫生标准分类的几种可能方案,着重讨论并提出整个劳动安全卫生标准体系的层次结构方框图。 相似文献
188.
Global food production and security rely heavily on finite reserves of newly mined phosphate for fertilizers. However, systemic inefficiencies result in the deposition in aquatic ecosystems of much of the phosphorus mined for food production causing costly eutrophication problems that damage aquatic ecosystems and human health. The Sustainable Phosphorus Alliance (SPA, formerly named North American Partnership for Phosphorus Sustainability) was created to implement sustainable phosphorus solutions through active engagement of stakeholders in both the private and public sectors. This paper describes a conceptual model of transformative change to a sustainable phosphorus system for the North American region. The model emerged from discussions at a series of formal and informal meetings held in conjunction with a ‘Future of Phosphorus’ event (National Science Foundation’s Phosphorus Sustainability Research Coordination Network) and an inaugural SPA Board meeting. Model development drew on the multi-level perspective of socio-technical transitions to develop a series of pathways to a transformed phosphorus system. The uses of the model and transition pathways are discussed in terms of their potential to form an important first step towards the development of a regional vision for improved phosphorus sustainability. The process provides an example of how research in sustainability science can contribute to action on environmental improvement. 相似文献
189.
为了对政府环境绩效审计的有关理论问题有一个系统深入的认识,促进环境绩效审计工作的发展,文章对政府环境绩效审计方式尤其是评价指标体系等方面的国内外研究进展进行了综述,对审计的核心内容、主要方法和实现途径进行了探讨,期望为我国环境绩效审计工作指标体系、核心内容、主要方法和实现途径等工作的开展提供借鉴作用。 相似文献
190.
建筑施工伤亡事故现状、原因及其对策 总被引:1,自引:1,他引:1
刘少华 《中国安全科学学报》1996,6(4):58-61,57
应用安全系统工程学原理及方法分析建筑行业伤亡事故增多的根本原因;综合阐述建筑安全的基本对策,以求标本兼治,使建筑施工伤亡严峻形势得到根本好转 相似文献