全文获取类型
收费全文 | 258篇 |
免费 | 64篇 |
国内免费 | 22篇 |
专业分类
安全科学 | 119篇 |
废物处理 | 4篇 |
环保管理 | 31篇 |
综合类 | 91篇 |
基础理论 | 32篇 |
污染及防治 | 8篇 |
评价与监测 | 6篇 |
社会与环境 | 16篇 |
灾害及防治 | 37篇 |
出版年
2023年 | 5篇 |
2022年 | 10篇 |
2021年 | 18篇 |
2020年 | 19篇 |
2019年 | 12篇 |
2018年 | 12篇 |
2017年 | 15篇 |
2016年 | 16篇 |
2015年 | 17篇 |
2014年 | 14篇 |
2013年 | 15篇 |
2012年 | 21篇 |
2011年 | 23篇 |
2010年 | 12篇 |
2009年 | 16篇 |
2008年 | 7篇 |
2007年 | 19篇 |
2006年 | 15篇 |
2005年 | 8篇 |
2004年 | 10篇 |
2003年 | 9篇 |
2002年 | 12篇 |
2001年 | 7篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1989年 | 2篇 |
1985年 | 1篇 |
1975年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有344条查询结果,搜索用时 203 毫秒
91.
J. G. Arnold R. Srinivasan R. S. Muttiah J. R. Williams 《Journal of the American Water Resources Association》1998,34(1):73-89
ABSTRACT: A conceptual, continuous time model called SWAT (Soil and Water Assessment Tool) was developed to assist water resource managers in assessing the impact of management on water supplies and nonpoint source pollution in watersheds and large river basins. The model is currently being utilized in several large area projects by EPA, NOAA, NRCS and others to estimate the off-site impacts of climate and management on water use, non-point source loadings, and pesticide contamination. Model development, operation, limitations, and assumptions are discussed and components of the model are described. In Part II, a GIS input/output interface is presented along with model validation on three basins within the Upper Trinity basin in Texas. 相似文献
92.
超大规模工业厂越来越多地应用于工业生产,但与我国现行防火技术规范存在突出的矛盾,有些地方甚至突破了我国现行防火技术规范。本文即对这一矛盾进行典型事例分析,并研究上应的安全措施。 相似文献
93.
Many development projects intended to exploit natural resourcesare occurring in fragile ecosystems, and therefore the need forsound biodiversity assessment and monitoring programs is growing.Large mammals are important components of these fragile ecosystems, yet there are few strategies that attempt to assess and monitor entire large mammal communities in relation to development projects. We propose the use of two indices applied within a framework of adaptive management. An occurrence indexassesses the composition and distribution of large mammals at a site, and an abundance index monitors the abundance of large mammals over time in relation to development. We discuss the design, applicability and effectiveness of these indices based onour experience with a natural gas development project in the Amazon forests of southeastern Peru. 相似文献
94.
95.
夹层电缆引发火灾的实验研究 总被引:1,自引:0,他引:1
模拟现代建筑夹层中贮藏大量未加金属导管防护的电线电缆所引发的火灾效应.在一个全尺寸燃烧套房模型中进行了起火室和顶棚夹层空间电缆火灾的实验研究,并采用大涡模拟的方法对实验中烟气速度场进行了数值模拟.结果表明,加明火源可以加强电缆的火灾功率;通风状况对夹层电缆火灾的温度场、烟气遮光度和火灾功率有明显影响.电缆燃烧产物中主要毒性气体为CO.电缆在夹层燃烧时,CO和CO2浓度均高于目标室和起火室中的浓度.而夹层毒气最为集中,其CO浓度远远超出OSHA和IDLH标准.电缆在夹层燃烧时发生火灾的危险性较大. 相似文献
96.
喷雾降尘在凡口铅锌矿的应用 总被引:1,自引:0,他引:1
介绍了喷雾降尘技术在凡口铅锌矿井下大斜坡道的应用情况,并对该技术进行了评价。 相似文献
97.
烟气输运和水喷淋相互作用的大涡模拟研究 总被引:2,自引:0,他引:2
本文应用大涡模拟方法,并结合Smagorinsky亚格子尺度模型,数值研究了烟气输运和水喷淋的相互作用问题。为了有效地模拟烟气输运过程,文中采用低马赫数近似下的三维可压缩Navier-Stokes方程和组分方程进行求解,并采用有限差分法数值计算了滤波后的控制方程。对于燃烧过程扣所产生的热释放,采用Lagrangian粒子携带热量的近似方法来模拟,这些运动粒子进一步用来标识烟气的输运过程,同时还近似模拟了水喷淋和热气流的相互作用过程。文中数值计算了燃烧火源所形成的热气流和烟气输运过程,以及与水喷淋的相互作用,并探讨了喷水装置的喷水量、喷射角和水颗粒直径对流动特性的影响。 相似文献
98.
Setting the stage for the review of the international estimate of short-term intake (IESTI) equation
Anke Richter Christian Sieke Hermine Reich Bernadette C. Ossendorp Nicolas Breysse Jason Lutze 《Journal of environmental science and health. Part. B》2018,53(6):343-351
ABSTRACTIn the framework of setting Maximum Residue Limits (MRLs) for pesticides, both chronic and acute health risks to consumers arising from the long-term and short-term dietary exposure to pesticide residues have to be assessed. The current internationally harmonized approach for assessing the acute dietary exposure is based on deterministic methods for calculating the IESTI (International Estimate of Short-Term Intake). Recently, it became apparent that the IESTI approach needs a revision in the light of new scientific and political aspects. The main reasons that require this review were the lack of an international harmonization of the methodology which implies trade barriers as well as difficulties in risk communication concerning the public trust in regulatory systems. The most recent milestone in the scientific debate on a possible revision of the IESTI equation was an international scientific workshop held in Geneva in September 2015. The main objectives of this meeting were the re-evaluation, and where possible, the international harmonization of the input parameters for the IESTI equations as well as the equations themselves. The main recommendations from the workshop were (i) to replace the highest residue and supervised trials median residue with the maximum residue limit (MRL), (ii) to use a standard variability factor of three, (iii) to derive the P97.5 large portion value from the distribution of consumption values of dietary surveys expressed as kg food/kg bw/d, and (iv) to remove the commodity unit weight from the equations. In addition, the application of conversion factors and processing factors was addressed. On the initiative of the (World Health Organization) WHO Collaborating Centre on Chemical Food Safety at the National Institute for Public Health and the Environment (RIVM), the Netherlands, an international working group with members from the French Agency for Food, Environmental and Occupational Health and Safety, France (ANSES), Australian Pesticides and Veterinary Medicines Authority, Australia (APVMA), German Federal Institute for Risk Assessment, Germany (BfR), Chemical Regulation Division, the United Kingdom (CRD), European Food Safety Authority (EFSA), and RIVM, the Netherlands was formed after the IESTI workshop to conduct a comprehensive impact assessment of the proposed changes of the IESTI equations. 相似文献
99.
A lidar-based assessment of riparian shade and large wood potential in the Skagit River watershed,WA
Tim Hyatt 《Journal of the American Water Resources Association》2023,59(4):743-761
Wild salmon stocks in the Pacific Northwest are imperiled by a variety of declining habitat factors, including riparian shade and in-channel large wood. In this paper, a relatively simple lidar model of the riparian canopy was used along anadromous streams in the Skagit River watershed in western Washington State, United States, to delineate where riparian trees were most lacking, and where restoration efforts would have the greatest benefit in terms of shade and large wood recruitment potential. Within a 45-m riparian buffer, 61% of riparian zones were currently incapable of delivering large wood to the stream. Current potential for large wood recruitment is greatest adjacent to stream edges and falls off rapidly with distance from the channel. Approximately 99% of large wood recruitment potential lies within 45 m of the channel edge, and 50% of the wood potential is within 9 m. A hypothetical canopy model in which all trees mature to a 100-year height would provide 18% more shade distributed over the entire watershed, and 90% more shade in the tributaries. Most of the potential gains in improved shade and large wood contributions are in agricultural areas, as opposed to forestry or urban land uses. The shade and large wood models were constructed from widely available geographic information system tools and are readily transferable to other watersheds with similar characteristics. Model outputs are intended for use in planning restoration projects, as an input to stream temperature models, and to inform policy on restoration priorities and regulatory buffer widths. 相似文献
100.