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481.
在建设两型社会的大背景下,我院积极探索低碳经济管理途径,通过实施"四权分离物品管理机制"、全成本核算、打造数字化医院和低碳医疗等手段初步实现了低碳经济管理,并取得了极大的经济效益和社会效益。 相似文献
482.
Mercury (Hg) concentrations were monitored in wild and cultured fish collected from fresh and coastal waters in the Korean peninsula from April 2006 to August 2008 nationwide. Total Hg concentrations were reported for 5043 fish samples, including 78 species from 133 locations. Significant interspecies variation was noted in the Hg levels. The average Hg concentration in each fish species ranged from 6.31 μg kg−1 for mullet (Mugil cephalus) to 200 μg kg−1 for mandarin fish (Siniperca scherzeri). Among the species collected, the maximum concentration of Hg, 1720 μg kg−1, was measured in an Amur catfish (Silurus asotus). Only wild freshwater fish exceeded the WHO ingestion standard. Wild freshwater piscivorous fish samples from a large artificial upstream lake contained the highest Hg levels. Hg concentrations were compared between fish groups categorized as wild and farmed fish from freshwater and coastal waters. Although the wild freshwater fish had similar size ranges, their Hg concentrations were higher than those of the other groups. Compared to the feed of farmed marine and freshwater fishes, the prey of wild freshwater fish had a higher Hg concentration, and the total Hg concentrations in freshwater and associated sediment samples were higher than those in coastal water and associated sediment samples. In the freshwater environment, piscivorous fish bioaccumulated two times more Hg than carnivorous and omnivorous fish and four times more than planktivorous fish. The difference in Hg concentrations among trophic groups might have been due to differences in the size of fish, in addition to the variations among different trophic groups. These data will be useful for developing the fish consumption advisory as a management measure to reduce Hg exposure. 相似文献
483.
Rapid changes to the Arctic hydrological cycle challenge both our process understanding and our ability to find appropriate
adaptation strategies. We have investigated the relevance and accuracy development of climate change projections for assessment
of water cycle changes in major Arctic drainage basins. Results show relatively good agreement of climate model projections
with observed temperature changes, but high model inaccuracy relative to available observation data for precipitation changes.
Direct observations further show systematically larger (smaller) runoff than precipitation increases (decreases). This result
is partly attributable to uncertainties and systematic bias in precipitation observations, but still indicates that some of
the observed increase in Arctic river runoff is due to water storage changes, for example melting permafrost and/or groundwater
storage changes, within the drainage basins. Such causes of runoff change affect sea level, in addition to ocean salinity,
and inland water resources, ecosystems, and infrastructure. Process-based hydrological modeling and observations, which can
resolve changes in evapotranspiration, and groundwater and permafrost storage at and below river basin scales, are needed
in order to accurately interpret and translate climate-driven precipitation changes to changes in freshwater cycling and runoff.
In contrast to this need, our results show that the density of Arctic runoff monitoring has become increasingly biased and
less relevant by decreasing most and being lowest in river basins with the largest expected climatic changes. 相似文献
484.
Surface water concentrations of dissolved organic carbon ([DOC]) are changing throughout the northern hemisphere due to changes
in climate, land use and acid deposition. However, the relative importance of these drivers is unclear. Here, we use the Integrated
Catchments model for Carbon (INCA-C) to simulate long-term (1996–2008) streamwater [DOC] at the four Swedish integrated monitoring
(IM) sites. These are unmanaged headwater catchments with old-growth forests and no major changes in land use. Daily, seasonal
and long-term variations in streamwater [DOC] driven by runoff, seasonal temperature and atmospheric sulfate (SO4
2−) deposition were observed at all sites. Using INCA-C, it was possible to reproduce observed patterns of variability in streamwater
[DOC] at the four IM sites. Runoff was found to be the main short-term control on [DOC]. Seasonal patterns in [DOC] were controlled
primarily by soil temperature. Measured SO4
2− deposition explained some of the long-term [DOC] variability at all sites. 相似文献
485.
Atmospheric nitrogen deposition: revisiting the question of the importance of the organic component 总被引:2,自引:0,他引:2
Cornell SE 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2214-2222
The organic component of atmospheric reactive nitrogen plays a role in biogeochemical cycles, climate and ecosystems. Although its deposition has long been known to be quantitatively significant, it is not routinely assessed in deposition studies and monitoring programmes. Excluding this fraction, typically 25-35%, introduces significant uncertainty in the determination of nitrogen deposition, with implications for the critical loads approach. The last decade of rainwater studies substantially expands the worldwide dataset, giving enough global coverage for specific hypotheses to be considered about the distribution, composition, sources and effects of organic-nitrogen deposition. This data collation and meta-analysis highlights knowledge gaps, suggesting where data-gathering efforts and process studies should be focused. New analytical techniques allow long-standing conjectures about the nature and sources of organic N to be investigated, with tantalising indications of the interplay between natural and anthropogenic sources, and between the nitrogen and carbon cycles. 相似文献
486.
Pihl Karlsson G Akselsson C Hellsten S Karlsson PE 《Environmental pollution (Barking, Essex : 1987)》2011,159(12):3571-3582
Changes in sulphur and nitrogen pollution in Swedish forests have been assessed in relation to European emission reductions, based on measurements in the Swedish Throughfall Monitoring Network. Measurements were analysed over 20 years with a focus on the 12-year period 1996 to 2008. Air concentrations of SO2 and NO2, have decreased. The SO4-deposition has decreased in parallel with the European emission reductions. Soil water SO4-concentrations have decreased at most sites but the pH, ANC and inorganic Al-concentrations indicated acidification recovery only at some of the sites. No changes in the bulk deposition of inorganic nitrogen could be demonstrated. Elevated NO3-concentrations in the soil water occurred at irregular occasions at some southern sites. Despite considerable air pollution emission reductions in Europe, acidification recovery in Swedish forests soils is slow. Nitrogen deposition to Swedish forests continues at elevated levels that may lead to leaching of nitrate to surface waters. 相似文献
487.
Presence of pesticide residues was studied in rain water during 2002 employing multi residue analysis method by gas liquid
chromatography equipped with ECD and NPD detectors and capillary columns. The presence of pesticide residues in surface aquatic
system triggered the investigation of the presence of pesticides in rain water. A total of 13 pesticides were detected in
rain water samples. Among the different groups of pesticides, organochlorines were present in the range of 0.041–7.060 ppb
with maximum concentration of p,p’-DDT up to 7.060 μg l−1. Synthetic pyrethroids were present ranging from 0.100 to 1.000 μg l−1 and organophosphates in the range of 0.050–4.000 μg l−1 showing maximum contamination with cypermethrin (1.000 μg l−1) and monocrotophos (4.000 μg l−1) of the respective groups. Almost 80% samples showed the residues above MRL of 0.5 ppb fixed for multi residues and on the
basis of single pesticide, 16–50% samples contained residues above the MRL value of 0.1 ppb. 相似文献
488.
489.
490.
水污染的生物自动监测 总被引:1,自引:0,他引:1
生物监测是指有规则地或连续地评价一个或多个参数,而且可以用来测定有害状态。通过对生物监测领域发展状况的描述,建议水污染质量控制系统要把生物和化学-物理信息结合起来,并根据生物监测的数据进行修正,利用水生生物来及早地警报水体中存在有毒物质,并与电子计算机设备相结合,形成早期警报毒性监测系统,提出了发展生物自动监测系统的可行性,指出它在水污染控制中将成为必要的工具。 相似文献