全文获取类型
收费全文 | 282篇 |
免费 | 6篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 16篇 |
环保管理 | 59篇 |
综合类 | 37篇 |
基础理论 | 72篇 |
污染及防治 | 51篇 |
评价与监测 | 27篇 |
社会与环境 | 8篇 |
灾害及防治 | 4篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 7篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 4篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 10篇 |
2014年 | 14篇 |
2013年 | 20篇 |
2012年 | 10篇 |
2011年 | 22篇 |
2010年 | 6篇 |
2009年 | 10篇 |
2008年 | 17篇 |
2007年 | 13篇 |
2006年 | 9篇 |
2005年 | 10篇 |
2004年 | 4篇 |
2003年 | 8篇 |
2002年 | 11篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 8篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1970年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有288条查询结果,搜索用时 15 毫秒
231.
Eleven drinking water treatment plants, located downstream of textile plants or pulp and paper mills, have been sampled monthly during a year for the analysis of 17 nonylphenol ethoxylates (NP1-17EO) and two nonylphenoxycarboxylic acids (NP1-2EC). At all but one plant, results in the drinking water, for the sum of these 19 substances, range between below detection levels and 6.7 microg/l. Annual means are between 0.02 and 2.8 microg/l. At the other plant, the yearly average concentration is 10.4 microg/l and the monthly maximum is 43.3 microg/l. In the surface (pre-treatment) water, the annual mean concentrations of the 11 plants range between 0.14 and 17.8 microg/l and the recorded instantaneous maximum is 55.3 microg/l. According to Canadian health authorities, drinking water is a negligible route of human exposure to nonylphenolic compounds, even at the highest concentrations found in this study. After transformation of the data into nonylphenol equivalents, about 20% of the surface water samples exceed the Canadian 1 microg/l nonylphenol water quality guideline for the protection of aquatic life. Some results also exceed Québec's 6 microg/l nonylphenol guideline. The efficiency of the plants in removing nonylphenolic compounds from drinking water is highly variable, ranging from 11% to 99%. 相似文献
232.
233.
A pilot study of the relationship between multiple sclerosis and the physical environment in northwest Ireland 总被引:1,自引:0,他引:1
Multiple sclerosis (MS) is a neurological disease of unknown origin, but it is thought likely to have an environmental component in addition to genetic predisposition. It appears common in areas with underlying radon-producing granites. Radon exposure before the age of 15 years is postulated as a contributory cause in genetically susceptible individuals. Pilot studies were undertaken, with results which indicate that radon exposure may be a factor, and that the hypothesis warrants further investigation. 相似文献
234.
John D. Orbell Hien Van Dao Lawrence N. Ngeh Stephen W. Bigger Margaret Healy Rosalind Jessop Peter Dann 《Environmental Chemistry Letters》2005,3(1):25-27
We have conducted temperature-dependent studies on the removal of a solidified tarry residue from feathers using magnetic particles. These studies demonstrate an acute temperature dependency whereby no contaminant at all is removed below a certain temperature but, at and above this temperature, the removal rapidly approaches 100%. Significantly, this temperature is well below the temperature at which the tarry residue becomes a flowing liquid. This demonstrates that it is possible for magnetic cleansing to remove up to 100% of tarry residue from feathers under temperature conditions that would be benign to a bird. 相似文献
235.
Key Elements of Landscape Pattern Measures 总被引:9,自引:0,他引:9
236.
Antecedents of organizational and community embeddedness: The roles of support,psychological safety,and need to belong
下载免费PDF全文
![点击此处可从《组织行为杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Defining embeddedness as a psychological construct that influences individuals to stay, we draw on conservation of resources theory to develop and test a model of the influence of contextual social support resources on both organizational and community forms of embeddedness. In addition to the direct relationship between support and embeddedness, we also assess the mediating influence of organizational and community psychological safety and the moderating impact of need to belong. Using a multisource sample of employees and coworkers (N = 165), we found support for most of the hypotheses. Social support resources emanating from the organization and the community were positively associated with embeddedness in each domain, and psychological safety mediated these relationships. We also found that need to belong was an important boundary condition in the determination of organizational embeddedness. We discuss the theoretical contributions and practical implications of our findings. 相似文献
237.
Spatial Optimization of Six Conservation Practices Using Swat in Tile‐Drained Agricultural Watersheds
下载免费PDF全文
![点击此处可从《Journal of the American Water Resources Association》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Margaret M. Kalcic Jane Frankenberger Indrajeet Chaubey 《Journal of the American Water Resources Association》2015,51(4):956-972
Targeting of agricultural conservation practices to the most effective locations in a watershed can promote wise use of conservation funds to protect surface waters from agricultural nonpoint source pollution. A spatial optimization procedure using the Soil and Water Assessment Tool was used to target six widely used conservation practices, namely no‐tillage, cereal rye cover crops (CC), filter strips (FS), grassed waterways (GW), created wetlands, and restored prairie habitats, in two west‐central Indiana watersheds. These watersheds were small, fairly flat, extensively agricultural, and heavily subsurface tile‐drained. The targeting approach was also used to evaluate the model's representation of conservation practices in cost and water quality improvement, defined as export of total nitrogen, total phosphorus, and sediment from cropped fields. FS, GW, and habitats were the most effective at improving water quality, while CC and wetlands made the greatest water quality improvement in lands with multiple existing conservation practices. Spatial optimization resulted in similar cost‐environmental benefit tradeoff curves for each watershed, with the greatest possible water quality improvement being a reduction in total pollutant loads by approximately 60%, with nitrogen reduced by 20‐30%, phosphorus by 70%, and sediment by 80‐90%. 相似文献
238.
Kren C. Nelson Margaret A. Palmer 《Journal of the American Water Resources Association》2007,43(2):440-452
ABSTRACT: Multiple anthropogenic stressors, including increased watershed imperviousness, destruction of the riparian vegetation, increased siltation, and changes in climate, will impact streams over the coming century. These stressors will alter water temperature, thus influencing ecological processes and stream biota. Quantitative tools are needed to predict the magnitude and direction of altered thermal regimes. Here, empirical relationships were derived to complement a simple model of in‐stream temperature [developed by Caissie et al. Canadian Journal of Civil Engineering 25 (1998) 250; Journal of Hydrology 251 (2001) 14], including seasonal temperature shifts linked to land use, and temperature surges linked to localized rainstorms; surges in temperature averaged about 3.5°C and dissipated over about 3 h. These temperature surges occurred frequently at the most urbanized sites (up to 10% of summer days) and could briefly increase maximum temperature by >7°C. The combination of empirical relationships and model show that headwater streams may be more pervasively impacted by urbanization than by climate change, although the two stressors reinforce each other. A profound community shift, from common cold and coolwater species to some of the many warmwater species currently present in smaller numbers, may be expected, as shown by a count of days on which temperature exceeds the “good growth” range for coldwater species. 相似文献
239.
Previous research has documented the bioaccumulation of perfluoroalkyl compounds (PFCs) in apex predators in remote locations but few studies have evaluated urban estuaries. To assess the importance of PFCs in San Francisco Bay, two apex predators in the San Francisco Bay, double-crested cormorants (Phalacrocorax auritus) and Pacific harbor seals (Phoca vitulina richardii), were sampled. Prey fish (Atherinops affinis and Menidia audens) were also evaluated to better understand potential sources of PFCs to the foodweb. Perfluorooctane sulfonate (PFOS) was the primary PFC detected in cormorant eggs, small fish and harbor seal serum. PFOS detected in San Francisco Bay seal serum was typically an order of magnitude higher than those at the reference site. PFOS concentrations were highest in seals and cormorant eggs from the highly urbanized southern portion of the Bay. PFOS in eggs from the southern part of the Bay remained relatively constant between 2006 and 2009 despite the phase-out of perfluorosulfonyl-based compounds nationally. In addition, these levels exceed the avian predicted no effects concentration of 1.0 μg mL(-1). Concentrations of the remaining PFCs measured were substantially lower than those of PFOS. 相似文献
240.
Margaret S. Hrezo 《Journal of the American Water Resources Association》1986,22(6):1001-1009
ABSTRACT: Research suggests that conflict over public participation in water resource planning is due, in part, to confusion over the nature of the policies involved. This article examines the roadblocks to citizen involvement in water resource planning in terms of two policy models: (1) the Social Feasibility Model and (2) the Political Feasibility Model. Each model posits a different role for public participation. Although the Political Feasibility Model has been widely accepted in water resource planning, changes in the nature of the policies involved in water resource management have weakened its appropriateness. Currently, social and redistributive policies involving value conflicts often dominate water planning and these policies are best chosen through the Social Feasibility Model. The article discusses the nature of the social feasibility model, the new types of policy decisions facing water resource managers, and how the social feasibility model can help overcome the roadblocks to increased public participation in water resource policy making. 相似文献