全文获取类型
收费全文 | 1118篇 |
免费 | 108篇 |
国内免费 | 477篇 |
专业分类
安全科学 | 114篇 |
废物处理 | 14篇 |
环保管理 | 76篇 |
综合类 | 791篇 |
基础理论 | 389篇 |
污染及防治 | 134篇 |
评价与监测 | 141篇 |
社会与环境 | 37篇 |
灾害及防治 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 26篇 |
2022年 | 39篇 |
2021年 | 50篇 |
2020年 | 49篇 |
2019年 | 51篇 |
2018年 | 46篇 |
2017年 | 57篇 |
2016年 | 89篇 |
2015年 | 68篇 |
2014年 | 64篇 |
2013年 | 138篇 |
2012年 | 85篇 |
2011年 | 92篇 |
2010年 | 74篇 |
2009年 | 45篇 |
2008年 | 60篇 |
2007年 | 69篇 |
2006年 | 71篇 |
2005年 | 48篇 |
2004年 | 50篇 |
2003年 | 50篇 |
2002年 | 56篇 |
2001年 | 36篇 |
2000年 | 38篇 |
1999年 | 35篇 |
1998年 | 38篇 |
1997年 | 19篇 |
1996年 | 29篇 |
1995年 | 27篇 |
1994年 | 19篇 |
1993年 | 21篇 |
1992年 | 12篇 |
1991年 | 10篇 |
1990年 | 13篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 6篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有1703条查询结果,搜索用时 109 毫秒
871.
Preparedness of emergency evacuation for the leakage of toxic substances in chemical plants is very important in order to reduce damage. In order to implement an emergency evacuation properly, it is necessary to comprehensively and concretely determine the conditions of the leakage and atmospheric conditions and predict the consequences of the dispersed gases. Repeated training for emergencies is also essential. In order to realize effective evacuation, a prediction model of the evacuation area that anyone can use to obtain the same results both accurately and promptly is developed in the present study. The prediction model is designed such that the wind speed and atmospheric conditions are automatically set, and the leakage rate is the only input parameter, so that anyone can use the model easily. In addition, the model can also predict the atmospheric parameters for up to 3 h and can calculate the evacuation distance so that smooth evacuation can be achieved for changing atmospheric conditions. Finally, the evacuation area is defined by statistically analysed wind fluctuations, and a series of emergency evacuation measures is implemented. 相似文献
872.
873.
Marcela Capcarova Lubos Harangozo Tomas Toth Loretta Schwarczova Alica Bobkova Robert Stawarz 《Journal of environmental science and health. Part. B》2017,52(12):858-863
The objective of this study was to determine the concentrations of Cu, Cd, Pb, Mn, Cr, Co, Ni, Zn, and Hg in the white and fruit parts of commercially available yogurts (n = 30) from Nitra markets (Slovak Republic). The results were correlated to determine their relationships. Three yogurt fruit flavors were chosen and tested, strawberry (n = 10), blueberry (n = 10), and cherry (n = 10). The elements were analyzed using atomic absorption spectrophotometry. Higher concentrations of toxic elements, such as Cd and Pb, were found in the fruit parts of the yogurt, and in some cases, the tolerable limit was exceeded. The white part of the yogurt was not contaminated by toxic elements. White yogurt is a good source of nutrients for humans, but the fruit part in yogurt requires detailed monitoring and improvements in the processing techniques. 相似文献
874.
邻苯二甲酸二乙基己酯(DEHP)污染及其毒性研究进展 总被引:3,自引:0,他引:3
邻苯二甲酸二乙基己酯(DEHP)作为重要的增塑剂被广泛应用于涂料、食品包装、医疗器材、儿童玩具等产品中。研究表明DEHP在水、土壤、空气等各个环境要素以及食物、饮用水中已被普遍检出,并对环境产生潜在的危害。本文通过分析国内外DEHP的环境暴露和毒性效应的研究成果,总结了DEHP在室外大气、室内空气、土壤、地表水、地下水、食品和饮用水中的污染现状,并对DEHP的替代产品进行总结;此外,本文深入探讨了DEHP对水生生物和陆生生物的生态毒性效应,以及对生殖发育、肝脏、呼吸系统和神经系统等的健康毒性效应。最后,结合DEHP在环境暴露调查和毒性效应研究方面的不足,指出需要进一步加强我国DEHP的环境暴露调查,制定相关环境基准值与标准限值,开展慢性生态毒性效应和人体健康毒性效应等方面的研究。 相似文献
875.
876.
模拟火灾现场喷水灭火的情况条件,将高温下的混凝土喷水冷却,用扫描电子显微镜(SEM)分析混凝土的显微结构。研究发现,当受热温度低于300℃时,喷水冷却混凝土的显微结构与空气中自然冷却试样没有明显的差别。当受热温度达到300℃以后,冷却过程中的水会在混凝土中产生新的水化物,显微结构中发现有新的晶体。受热温度越高,新的水化物晶体就越多,同时混凝土的显微结构破坏越严重。这些特征可以用来鉴定火场中遏水冷却混凝土的受热温度。 相似文献
877.
Cram S Ponce De León CA Fernández P Sommer I Rivas H Morales LM 《Environmental monitoring and assessment》2006,121(1-3):127-149
Possible contaminants produced by the Petroleos Mexicanos (PEMEX) marine oil complex in the vicinity of the Cayo Arcas (Mexico) coral reef ecosystem were evaluated by analyzing sediments and sea water for hydrocarbons and metal elements. We found that the concentrations of aliphatic hydrocarbons in the sea water were generally low, with the highest values detected near the oil station; the concentration of polycyclic aromatic hydrocarbons (PAHs) was generally below the detection limit. The hydrocarbons found in the sediments seem to have a pyrogenic origin, and were probably produced by marine traffic in the study area. The total PAH concentration did not exceed the NOAA criteria, although levels of some individual PAHs did. The only metal detected in the sea water at high concentrations was nickel. The Ni/V ratio in the sediments indicates the contribution of crude oil to the system. The high content of Ni and Zn was attributed to the ballast waters from the oil tankers that load at the station's monobuoys. The presence of fine sediments that commonly originate from terrestrial ecosystems supported this assumption. 相似文献
878.
Raeymaekers B 《Environmental monitoring and assessment》2006,116(1-3):233-243
In order to establish a monitoring method to track long term changes of the amount of anthropogenic contamination in a district
of Bavaria (Germany), a biomonitoring campaign with honey bees was performed in spring 2002. Expected anomalies from the industry
or from residential areas in the sampled district could not be detected. An anomaly over a considerable part of the sampling
area correlating with other phenomena lead to the hypothesis of a prehistoric cosmic impact. Moreover a principal component
analysis of the data showed evidence for a biogenic, an anthropogenic and an unknown component hypothetically related to a
possible cosmic impact. 相似文献
879.
Introduction of the Factor of Partitioning in the Lithogenic Enrichment Factors of Trace Element Bioaccumulation in Plant Tissues 总被引:1,自引:0,他引:1
Bioindicators are widely used in the study of trace elements inputs into the environment and great efforts have been conducted to separate atmospheric from soil borne inputs on biomass accumulation. Many monitoring studies of trace element pollution take into account the dust particles located in the plant surface plus the contents of the plant tissues. However, it is usually only the trace element content in the plant tissues that is relevant on plant health. Enrichment factor equations take into account the trace element enrichment of biomasses with respect soil or bedrocks by comparing the ratios of the trace element in question to a lithogenic element, usually Al. However, the enrichment equations currently in use are inadequate because they do not take into account the fact that Al (or whichever reference element) and the element in question may have different solubility-absorption-retention levels depending on the rock and soil types involved. This constrain will become critical when results from different sites are compared and so in this article we propose that the solubility factors of each element are taken into account in order to overcome this constrain. We analysed Sb, Co, Ni, Cr, Pb, Cd, Mn, V, Zn, Cu, As, Hg, and Al concentration in different zones of Catalonia (NE Spain) using the evergreen oak Quercus ilex and the moss Hypnum cupressiforme as target species. We compared the results obtained in rural and non industrial areas with those from the Barcelona Metropolitan Area. We observed differences in Al concentrations of soils and bedrocks at each different site, together with the differences in solubility between Al and the element in question, and a weak correlation between total soil content and water extract content through different sites for most trace elements. All these findings show the unsuitability of the current enrichment factors for calculating lithospheric and atmospheric contributions to trace element concentrations in biomass tissues. The trace element enrichment factors were calculated by subtracting the part predicted by substrate composition (deduced from water extracts from soils and bedrock) from total concentrations. Results showed that for most of the trace elements analysed, trace elements enrichment factors were higher inside the Barcelona Metropolitan Area than outside, a finding that indicates that greater atmospheric inputs occur in urban areas. The results show that the most useful and correct way of establishing a reference for lithospheric and atmospheric inputs into the plant tissues is, first, to analyse samples of the same plant species collected from a number of sites possessing similar environmental conditions (climate, vegetation type, soil type) and, second, to use this new enrichment factor obtained by subtracting from the total concentration in plant tissue the predicted contribution of soil or bedrock extracts instead of that of total soil or bedrock concentrations. 相似文献
880.
Dragun Z Raspor B Erk M Ivanković D Pavicić J 《Environmental monitoring and assessment》2006,114(1-3):49-64
The influence of the biometric parameters (shell mass, whole soft tissue mass, condition index) on MT and metal levels in the heat-treated cytosol of the whole soft tissue of transplanted mussels was studied over the period of one year. The positive correlation of three metals (Cd, Fe, Zn) with the shell mass indicated to time-dependent increase of their contents. Strong correlation of Mn content with the whole soft tissue mass (r = 0.74, p < 0.0001), and almost identical changes of these two parameters over the year make Mn a good indicator of mussel's condition. As opposed to the other metals, Cu content does not exhibit connection with biometry. On the other hand, MTs are highly influenced by biometry. As much as 65% of their variability could be explained by the changes of the shell mass and the whole soft tissue mass. Consequently, it is difficult to distinguish if the obtained positive correlation between Cd and MTs (r = 0.48, p < 0.05) reflects MT induction by Cd, or Cd accumulation as a result of age-dependent increase of MTs. Due to the strong influence of the biometry on MT level, the whole soft tissue is not considered as the best choice for measuring MTs as a biomarker. Better option would be to isolate a specific tissue that shows indisputable connection between MT induction and metal accumulation. 相似文献