首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   596篇
  免费   12篇
  国内免费   7篇
安全科学   14篇
废物处理   39篇
环保管理   42篇
综合类   78篇
基础理论   157篇
污染及防治   185篇
评价与监测   54篇
社会与环境   44篇
灾害及防治   2篇
  2023年   7篇
  2022年   20篇
  2021年   14篇
  2020年   8篇
  2019年   12篇
  2018年   26篇
  2017年   26篇
  2016年   34篇
  2015年   15篇
  2014年   32篇
  2013年   50篇
  2012年   42篇
  2011年   55篇
  2010年   34篇
  2009年   38篇
  2008年   30篇
  2007年   35篇
  2006年   25篇
  2005年   26篇
  2004年   16篇
  2003年   15篇
  2002年   4篇
  2001年   9篇
  2000年   9篇
  1999年   2篇
  1997年   3篇
  1996年   3篇
  1995年   1篇
  1993年   3篇
  1992年   1篇
  1991年   4篇
  1990年   3篇
  1989年   1篇
  1988年   1篇
  1986年   2篇
  1972年   2篇
  1966年   1篇
  1960年   1篇
  1958年   1篇
  1957年   1篇
  1956年   1篇
  1955年   1篇
  1943年   1篇
排序方式: 共有615条查询结果,搜索用时 15 毫秒
141.
142.
The Marano and Grado Lagoon is well known for being contaminated by mercury(Hg) from the Idrija mine(Slovenia) and the decommissioned chlor-alkali plant of Torviscosa(Italy).Experimental activities were conducted in a local fish farm to understand Hg cycling at the sediment–water interface. Both diffusive and benthic fluxes were estimated in terms of chemical and physical features. Mercury concentration in sediments(up to 6.81 μg/g)showed a slight variability with depth, whereas the highest methylmercury(MeHg) values(up to 10 ng/g) were detected in the first centimetres. MeHg seems to be produced and stored in the 2–3 cm below the sediment–water interface, where sulphate reducing bacteria activity occurs and hypoxic–anoxic conditions become persistent for days. DMeHg in porewaters varied seasonally(from 0.1 and 17% of dissolved Hg(DHg)) with the highest concentrations in summer. DHg diffusive effluxes higher(up to 444 ng/m~2/day) than those reported in the open lagoon(~ 95 ng/m~2/day), whereas DMeHg showed influxes in the fish farm(up to-156 ng/m~2/day). The diurnal DHg and DMeHg benthic fluxes were found to be higher than the highest summer values previously reported for the natural lagoon environment. Bottom sediments, especially in anoxic conditions, seem to be a significant source of MeHg in the water column where it eventually accumulates. However, net fluxes considering the daily trend of DHg and DMeHg, indicated possible DMeHg degradation processes. Enhancing water dynamics in the fish farm could mitigate environmental conditions suitable for Hg methylation.  相似文献   
143.
This study evaluated the use of sugarcane filter cake and nitrogen, phosphorus and potassium (NPK) fertilization in the bioremediation of a soil contaminated with diesel fuel using a completely randomized design. Five treatments (uncontaminated soil, T1; soil contaminated with diesel, T2; soil contaminated with diesel and treated with 15 % (wt) filter cake, T3; soil contaminated with diesel and treated with NPK fertilizer, T4; and soil contaminated with diesel and treated with 15 % (wt) filter cake and NPK fertilizer, T5) and four evaluation periods (1, 60, 120, and 180 days after the beginning of the experiment) were used according to a 4?×?5 factorial design to analyze CO2 release. The variables total organic carbon (TOC) and total petroleum hydrocarbons (TPH) remaining in the soil were analyzed using a 5?×?2 factorial design, with the same treatments described above and two evaluation periods (1 and 180 days after the beginning of the experiment). In T3 and T5, CO2 release was significantly higher, compared with the other treatments. Significant TPH removal was observed on day 180, when percent removal values were 61.9, 70.1, 68.2, and 75.9 in treatments T2, T3, T4, and T5, respectively, compared with the initial value (T1).  相似文献   
144.
145.
Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species–people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy’s regions (average area 15,000 km2) and provinces (2,900 km2). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population–biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.  相似文献   
146.
147.
148.
Environmental Science and Pollution Research - Microplastic pollution is one of the greatest environmental concerns for contemporary times and the future. In the last years, the number of...  相似文献   
149.
Environmental Chemistry Letters - Food spoilage is a major global concern due to the lack of proper packaging technology. Nanotechnology is expected to improve food packaging. Indeed, novel...  相似文献   
150.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号