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排序方式: 共有5779条查询结果,搜索用时 625 毫秒
981.
982.
983.
针对运输巷胶带蔓延火灾及火灾期间高温毒害烟气严重威胁下风侧人员和救援工作等问题,借助FDS软件构建运输巷胶带蔓延火灾模型,并基于水雾冷却降温和稀释阻挡火灾烟气扩散原理,研究胶带蔓延火灾烟气中的水雾阻烟抑制性能影响因素.结果表明:水雾对运输巷的胶带蔓延火灾具有冷却和熄灭作用,可减缓或者抑制蔓延火灾的进一步发展,对水雾下风... 相似文献
984.
通过分析与电子废物回收处理密切联系的工艺技术、规划管理和各种外部环境等因素,剖析我国电子废物处理产业面临的障碍,并提出解决建议。 相似文献
985.
River damming provides a dominant human impact on river environments worldwide, and while local impacts of reservoir flooding
are immediate, subsequent ecological impacts downstream can be extensive. In this article, we assess seven research strategies
for analyzing the impacts of dams and river flow regulation on riparian ecosystems. These include spatial comparisons of (1)
upstream versus downstream reaches, (2) progressive downstream patterns, or (3) the dammed river versus an adjacent free-flowing
or differently regulated river(s). Temporal comparisons consider (4) pre- versus post-dam, or (5) sequential post-dam conditions.
However, spatial comparisons are complicated by the fact that dams are not randomly located, and temporal comparisons are
commonly limited by sparse historic information. As a result, comparative approaches are often correlative and vulnerable
to confounding factors. To complement these analyses, (6) flow or sediment modifications can be implemented to test causal
associations. Finally, (7) process-based modeling represents a predictive approach incorporating hydrogeomorphic processes
and their biological consequences. In a case study of Hells Canyon, the upstream versus downstream comparison is confounded
by a dramatic geomorphic transition. Comparison of the multiple reaches below the dams should be useful, and the comparison
of Snake River with the adjacent free-flowing Salmon River may provide the strongest spatial comparison. A pre- versus post-dam
comparison would provide the most direct study approach, but pre-dam information is limited to historic reports and archival
photographs. We conclude that multiple study approaches are essential to provide confident interpretations of ecological impacts
downstream from dams, and propose a comprehensive study for Hells Canyon that integrates multiple research strategies. 相似文献
986.
Del-Pilar-Ruso Y De-la-Ossa-Carretero JA Giménez-Casalduero F Sánchez-Lizaso JL 《Environmental pollution (Barking, Essex : 1987)》2008,156(2):240-250
Desalination is a growing activity that has introduced a new impact, brine discharge, which may affect benthic communities. Although the role of polychaetes as indicators to assess organic pollution is well known, their tolerance to salinity changes has not been examined to such a great extent. The aim of this study was to examine the effect of brine discharge over soft bottom polychaete assemblage along the Alicante coast (Southeast Spain) over a two year period. Changes in the polychaete assemblage was analysed using univariate and multivariate techniques. We compared a transect in front of the discharge with two controls. At each transect we sampled at three depths (4, 10 and 15 m) during winter and summer. We have observed different sensitivity of polychaete families to brine discharges, Ampharetidae being the most sensitive, followed by Nephtyidae and Spionidae. Syllidae and Capitellidae showed some resistance initially, while Paraonidae proved to be a tolerant family. 相似文献
987.
Impacts on industry of Europe's emerging chemicals policy REACh 总被引:1,自引:0,他引:1
For Europe, a new regime in chemicals regulation is about to start. After the proposal of the European Commission concerning the Registration, Evaluation and Authorization of Chemicals (REACh) passed its readings in the European Parliament and some differences with the European Council of Ministers were resolved, the regulation will come into force in June 2007. This paper is focused on the question how serious the cost burdens for industry induced by REACh will be, and whether the New European Member States (NMS) which joined the European Union in May 2004 will be able to cope with the regulation. This evaluation has been done by assessing the legislative, administrative and economic framework in New Member States and by analysing real business cases in companies. The empirical showcase business impact studies are at the same time of interest for companies of EU-15 states, other European countries who may implement the regulation, and even for exporters of raw materials and chemicals outside Europe, who will also have to comply with REACh if they market in the European Community. The results give no indications that REACh adoption will bring significant drawbacks to companies in the NMS. The emerging regulation will bring challenges for individual companies, especially for small and medium-sized ones, but for the European chemical industry as a whole, there is no question that it will be able to cope with REACh burdens without losing its global competitiveness. 相似文献
988.
989.
Comparison of China’s Environmental Impact Assessment (EIA) Law with the European Union (EU) EIA Directive 总被引:1,自引:0,他引:1
In this paper, we first review the development of China’s Environmental Impact Assessment (EIA) system in the past 30 years.
Then we compare the framework and operational procedures of China’s new EIA law with those of the EU EIA Directive. We also
compare public participation, as well as sanctions and control in the two EIA systems. In addition, we identify where the
processes in both EIA systems are similar or different from one another. By comparison, we noted that there are at least three
obvious weaknesses in China’s EIA system: (1) the application of new models for EIA legislation; (2) the improvement of EIA
guidance and education; and (3) the enhancement of public participation in EIA process. Our study indicates that these three
major shortcomings should be overcome and improved in China’s EIA system, when compared with the EU EIA system. 相似文献
990.
Lemly AD 《Environmental monitoring and assessment》2007,125(1-3):361-375
This paper gives step-by-step instructions for assessing aquatic selenium hazards associated with mining. The procedure was
developed to provide the U.S. Forest Service with a proactive capability for determining the risk of selenium pollution when
it reviews mine permit applications in accordance with the National Environmental Policy Act (NEPA). The procedural framework
is constructed in a decision-tree format in order to guide users through the various steps, provide a logical sequence for
completing individual tasks, and identify key decision points. There are five major components designed to gather information
on operational parameters of the proposed mine as well as key aspects of the physical, chemical, and biological environment
surrounding it — geological assessment, mine operation assessment, hydrological assessment, biological assessment, and hazard
assessment. Validation tests conducted at three mines where selenium pollution has occurred confirmed that the procedure will
accurately predict ecological risks. In each case, it correctly identified and quantified selenium hazard, and indicated the
steps needed to reduce this hazard to an acceptable level. By utilizing the procedure, NEPA workers can be confident in their
ability to understand the risk of aquatic selenium pollution and take appropriate action. Although the procedure was developed
for the Forest Service it should also be useful to other federal land management agencies that conduct NEPA assessments, as
well as regulatory agencies responsible for issuing coal mining permits under the authority of the Surface Mining Control
and Reclamation Act (SMCRA) and associated Section 401 water quality certification under the Clean Water Act. Mining companies
will also benefit from the application of this procedure because priority selenium sources can be identified in relation to
specific mine operating parameters. The procedure will reveal the point(s) at which there is a need to modify operating conditions
to meet environmental quality goals. By recognizing concerns early in the NEPA process, it may be possible for a mining company
to match operational parameters with environmental requirements, thereby increasing the likelihood that the permit application
will be approved. 相似文献