全文获取类型
收费全文 | 3091篇 |
免费 | 43篇 |
国内免费 | 25篇 |
专业分类
安全科学 | 164篇 |
废物处理 | 155篇 |
环保管理 | 623篇 |
综合类 | 353篇 |
基础理论 | 743篇 |
环境理论 | 5篇 |
污染及防治 | 766篇 |
评价与监测 | 216篇 |
社会与环境 | 116篇 |
灾害及防治 | 18篇 |
出版年
2023年 | 22篇 |
2022年 | 37篇 |
2021年 | 26篇 |
2020年 | 21篇 |
2019年 | 32篇 |
2018年 | 67篇 |
2017年 | 68篇 |
2016年 | 89篇 |
2015年 | 59篇 |
2014年 | 84篇 |
2013年 | 292篇 |
2012年 | 144篇 |
2011年 | 181篇 |
2010年 | 121篇 |
2009年 | 125篇 |
2008年 | 162篇 |
2007年 | 189篇 |
2006年 | 157篇 |
2005年 | 108篇 |
2004年 | 106篇 |
2003年 | 119篇 |
2002年 | 89篇 |
2001年 | 67篇 |
2000年 | 47篇 |
1999年 | 51篇 |
1998年 | 39篇 |
1997年 | 43篇 |
1996年 | 44篇 |
1995年 | 40篇 |
1994年 | 43篇 |
1993年 | 34篇 |
1992年 | 37篇 |
1991年 | 26篇 |
1990年 | 29篇 |
1989年 | 20篇 |
1988年 | 14篇 |
1987年 | 20篇 |
1986年 | 26篇 |
1985年 | 17篇 |
1984年 | 18篇 |
1983年 | 29篇 |
1982年 | 29篇 |
1981年 | 27篇 |
1980年 | 19篇 |
1979年 | 18篇 |
1977年 | 11篇 |
1976年 | 9篇 |
1975年 | 11篇 |
1974年 | 11篇 |
1971年 | 11篇 |
排序方式: 共有3159条查询结果,搜索用时 62 毫秒
261.
Wastewater treatment works effluent is often considered to be one of the most important point sources of a wide range of anthropogenic contaminants to aquatic systems, however, this paper discusses other potential sources. With the aim of establishing the important sources of UV filters, insect repellent and biocides to the aquatic environment, samples were collected from sites with direct (bathing areas and marinas) and indirect (sites receiving wastewater effluent) human influences. Sunscreens containing UV filters are used in large volumes during the summer months and often applied shortly before a person enters the water for swimming activities. The results presented here demonstrate that washing directly from the skin is an important point source of 4 UV filters to the Oslofjord. The insect repellent, diethyl toluamide, was also measured and it was concluded that washing from the skin was not such an important point source into the fjord. Concentrations of the biocide Irgarol 1051 were also measured and were elevated in the small boat marina and surrounding enclosed area. This work demonstrates that man recreational water-based activities are a diffuse source of some contaminants into coastal and fjord environments and this study provides an initial assessment of the levels being released. 相似文献
262.
Samples of soil, plants, and lichens were analysed for heavy metal content (Cd, Cr, Cu, Ni, Pb, and Zn) in relation to different distances from the tunnel ventilation systems in order to evaluate the environmental pollution caused by car exhausts pollution from the Tauerntunnel and the Katschbergtunnel (Austria). Results show that the extent of heavy metal pollution is related to the type of tunnel ventilation system. The vertical ventilation system which ends in an exhaust air tower in the alpine pasture of Mosermandl 1,900 m above sea level contaminates soils and plants up to a distance of 750 m from the exhaust source. The dispersion of metals in front of the horizontal ventilation systems, which are located next to the tunnel portals, exhibits a rapid decrease with distance. Lichen transplants placed in front of the horizontal ventilation systems show very high metal accumulation, which gradually declines with the distance from the emitter source, therefore the lichen species Pseudevernia furfuracea can be used as a very efficient biomonitor for monitoring heavy metal pollution caused by tunnel exhausts over time. Data from former years (1986, 1988, 1990 and 1992) and from this present research suggest that the contamination of heavy metals at Mosermandl has decreased slightly in soil samples, except for Cu, but increased in plant samples, whereas a significant increase of Pb was observed. 相似文献
263.
Emmanuel C. Gentil Anders Damgaard Michael Hauschild Göran Finnveden Ola Eriksson Susan Thorneloe Pervin Ozge Kaplan Morton Barlaz Olivier Muller Yasuhiro Matsui Ryota Ii Thomas H. Christensen 《Waste management (New York, N.Y.)》2010,30(12):2636-2648
A number of waste life cycle assessment (LCA) models have been gradually developed since the early 1990s, in a number of countries, usually independently from each other. Large discrepancies in results have been observed among different waste LCA models, although it has also been shown that results from different LCA studies can be consistent. This paper is an attempt to identify, review and analyse methodologies and technical assumptions used in various parts of selected waste LCA models. Several criteria were identified, which could have significant impacts on the results, such as the functional unit, system boundaries, waste composition and energy modelling. The modelling assumptions of waste management processes, ranging from collection, transportation, intermediate facilities, recycling, thermal treatment, biological treatment, and landfilling, are obviously critical when comparing waste LCA models.This review infers that some of the differences in waste LCA models are inherent to the time they were developed. It is expected that models developed later, benefit from past modelling assumptions and knowledge and issues. Models developed in different countries furthermore rely on geographic specificities that have an impact on the results of waste LCA models. The review concludes that more effort should be employed to harmonise and validate non-geographic assumptions to strengthen waste LCA modelling. 相似文献
264.
Annekatrin Wagner Stephan Hülsmann Lothar Paul Rüdiger J. Paul Thomas Petzoldt René Sachse Thomas Schiller Bettina Zeis Jürgen Benndorf Thomas U. Berendonk 《Marine Biology》2012,159(11):2543-2559
To predict the coherence in local responses to large-scale climatic forcing among aquatic systems, we developed a generalized approach to compare long-term data of dimictic water bodies based on phenomenologically defined hydrographic events. These climate-sensitive phases (inverse stratification, spring overturn, early thermal stratification, summer stagnation) were classified in a dual code (cold/warm) based on threshold temperatures. Accounting for a latitudinal gradient in seasonal timing of phases derived from gradients in cumulative irradiation (2.2?days per degree latitude), we found a high spatial and temporal coherence in warm–cold patterns for six lakes (84?%) and the Baltic Sea (78?%), even when using the same thresholds for all sites. Similarity to CW-codes for the North Sea still was up to 72?%. The approach allows prediction of phase-specific warming trends and resulting instantaneous or time-delayed ecological responses. Exemplarily, we show that warming during early thermal stratification controls food-web-mediated effects on key species during summer. 相似文献
265.
Vikram K. Iyengar Thomas Castle Sean P. Mullen 《Behavioral ecology and sociobiology》2014,68(2):275-282
Divergence of sexual signals in sympatry can arise as a consequence of (1) interspecific competition for resources, (2) selection against maladaptive hybridization, or (3) as a result of selection to reduce the cost of interspecific aggression; termed agonistic character displacement (ACD). Calopterygid damselflies have emerged as a model system for studying the evolution of divergent sexual signals due to the repeated evolution of sympatric species pairs with fully and partially melanized wings. Damselfly wing patterns function during both courtship and territory defense. However, the relative contributions of natural and sexual selection to phenotypic divergence and enhanced isolation in sympatry remain unclear in many cases. Here, we investigated the hypothesis that interference competition, in the form of increased interspecific male–male aggression, drives the evolution of character displacement in sympatry between two species of North American damselflies, Calopteryx aequabilis and Calopteryx maculata, that show no evidence of ecological divergence or ongoing hybridization. In paired behavioral trials, we found that interspecific male aggression related to territory defense varied between site, species, and as a function of the relative abundance of con- vs. hetero-specific males. Specifically, we found that large-spotted C. aequabilis males received increased intra- and interspecific aggression but that aggression against large-spotted males declined during the middle of the flight season when both species were equally abundant. Based on these results, we suggest that ACD leads to enhanced species recognition, and may be a common outcome of the antagonism between interspecific male–male competition and the countervailing force of intraspecific sexual selection favoring increased wing melanization among territorial damselfly species. 相似文献
266.
267.
Meghan Ellis Thomas Gunton Murray Rutherford 《Journal of environmental management》2010,91(6):1268-1277
Sustainable environmental management is contingent on having an effective environmental planning system. A new methodology for designing and evaluating environmental planning systems is described and applied to a case study evaluation of the Canadian environmental planning process. The methodology is based on eight international best practice principles for environmental planning and 45 indicators. The research illustrates the benefits of the evaluation methodology in identifying how to improve environmental planning systems to achieve desired results. The methodology is applicable to a wide variety of jurisdictions. 相似文献
268.
Thomas W. Sloan 《Journal of Cleaner Production》2011,19(2-3):173-186
Equipment replacement is a fact of life in every industrial setting, and this paper seeks to answer the question: How can firms and policy makers effectively balance environmental and economic concerns with respect to replacement decisions? A replacement model which includes both economic and environmental factors is presented. One must decide whether to keep the existing technology, upgrade to a newer technology which produces a smaller environmental burden, or wait for an even newer, cleaner technology which may be introduced soon. More than 25 000 test problems are solved, examining different objectives and covering a wide range of applications. Including environmental costs does not lead to a consistent increase in the adoption of cleaner technologies; however, including incentives to adopt newer technologies does. When one accounts for the environmental impact of producing new equipment and disposing of old equipment, earlier adoption of new technologies actually increases the total environmental burden in some cases. 相似文献
269.
Don H. Kampbell John T. Wilson Harvey W. Read Thomas T. Stocksdale 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1236-1240
Soil removal of propane, isobutane and n-butane from a waste air stream was evaluated in the laboratory and in a prototype soil bioreactor. Laboratory investigations indicated first-order kinetics and the potential to degrade light aliphatic hydrocarbons and trichlorethylene, a compound ordinarily resistant to aerobic biological treatment. The predicted behavior of the bioreactor, based on laboratory studies, agreed closely with the actual behavior of the Reid system. The prototype bioreactor reduced the hydrocarbon concentrations in the air by at least 90percent with a residence time of 15 minutes and a pressure drop of 85 cm of water. The bioreactor functioned well through a range of temperatures, 12°C to 24°C. 相似文献
270.
Speed-accuracy tradeoffs are a common feature of decision-making processes, both in individual animals and in groups of animals
working together to reach a single collective decision. Individual organisms display consistent differences in their “impulsivity,”
and vary in their tendency to make rapid, impulsive choices as opposed to slower, more accurate decisions. However, we do
not yet know whether groups of animals consistently differ in their tendency to prioritize decision speed over accuracy. We
challenged 17 swarms of honey bees (Apis mellifera) to simultaneously choose a new nest site in each of three locations, and measured their decision speeds in each trial. We
found that swarms displayed consistent personality differences in the number of waggle dances and shaking signals they performed
and in how actively they scouted for new nest sites. However, swarms did not consistently differ in how long they took to
choose a nest site. We suggest that house-hunting A. mellifera swarms may place an especially high emphasis on decision accuracy when choosing a nest site, and that chance events—such
as the time when each swarm discovers a sufficiently high-quality nest site—may consequently play a greater role in determining
a swarm’s decision speed than intrinsic characteristics such as a swarm’s “impulsivity.” 相似文献