全文获取类型
收费全文 | 757篇 |
免费 | 156篇 |
国内免费 | 50篇 |
专业分类
安全科学 | 49篇 |
废物处理 | 38篇 |
环保管理 | 45篇 |
综合类 | 297篇 |
基础理论 | 129篇 |
污染及防治 | 327篇 |
评价与监测 | 33篇 |
社会与环境 | 24篇 |
灾害及防治 | 21篇 |
出版年
2024年 | 6篇 |
2023年 | 16篇 |
2022年 | 41篇 |
2021年 | 23篇 |
2020年 | 27篇 |
2019年 | 22篇 |
2018年 | 27篇 |
2017年 | 37篇 |
2016年 | 42篇 |
2015年 | 42篇 |
2014年 | 48篇 |
2013年 | 76篇 |
2012年 | 54篇 |
2011年 | 58篇 |
2010年 | 39篇 |
2009年 | 32篇 |
2008年 | 43篇 |
2007年 | 34篇 |
2006年 | 38篇 |
2005年 | 27篇 |
2004年 | 21篇 |
2003年 | 36篇 |
2002年 | 16篇 |
2001年 | 21篇 |
2000年 | 21篇 |
1999年 | 17篇 |
1998年 | 15篇 |
1997年 | 12篇 |
1996年 | 12篇 |
1995年 | 19篇 |
1994年 | 11篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 7篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1985年 | 3篇 |
1975年 | 1篇 |
排序方式: 共有963条查询结果,搜索用时 15 毫秒
111.
利用正交试验方法优化了净化烹饪油污菌种选育的环境和营养条件 ,即 :油 :2 0mL、NaNO3( 2g L) :4mL、KH2 PO4( 0 .5g L) :3mL、微量元素溶液 (CuSO4·5H2 O 0 .0 3g L ,ZnSO4·7H2 O 0 .1g L ,MnCl2 ·4H2 O 0 .0 5g L) :1mL和温度 3 7℃ ;而且得出氮源是影响菌体增长的最重要因素 ,温度是影响微生物降解的重要因素 ,而微量元素和磷源对菌种培育结果影响较小。在此优化条件下选育出了合适降解烹饪油污的c种子菌液 ,其每天可降解油 2 2mg L以上 ,并鉴定出主要的微生物是嗜水性气单孢菌 (Aeromonashydrophila 4AK4)、黄丝藻属 (Tribonema)和多甲藻属 (Peridinium)等菌体 ;分析了选育过程活性微生物、目标污染物和微生物的代谢产物三者之间的关系 ,发现所选微生物能利用油类物质作为碳源进行生长代谢 相似文献
112.
113.
采用物种敏感度排序法(SSR)对我国铅的淡水水生生物安全基准进行推导,并以太湖为例进行了流域水生生物安全基准推导。对于难以获得的本土生物毒性数据,开展了相应的毒性试验。获得了我国国家与太湖流域铅的水生生物安全基准值,基准最大浓度(CMC)分别为63.92、104.26 μg·L-1,基准连续浓度(CCC)分别为1.21、4.06 μg·L-1。同时,对我国主要河流以及太湖流域进行了铅的生态风险评价,联合概率曲线法显示影响5%水生生物种类的概率分别为66.22%和43.19%,熵值法则显示中国主要河流存在较大的铅暴露风险,因此,我国铅的潜在生态风险较大,主要河流与太湖流域存在铅污染问题。 相似文献
114.
高邮人有筑台御水的传统。据明隆庆《高邮州老·建置志》记载:“秦并楚、(高邮)又居秦,始建台,置邮亭,名秦邮。”说明秦朝在建高邮亭时曾先筑高台,又因邮亭是建在高高的土台上,便被形象地称为“高邮亭”,且邮亭系秦所建,故后人又称高邮为“秦邮”。秦代建高邮亭时为什么要先筑高台呢?这是因为高邮地处里下河地区,地势低洼,不筑台就不能抵御洪水。高邮 相似文献
115.
Chung-Yi Chung Jen-Jeng Chen Chang-Gai Lee Chun-Yen Chiu Wen-Liang Lai Shao-Wei Liao 《Environmental monitoring and assessment》2011,173(1-4):499-517
This work investigated sediment samples collected from Dapeng Bay and three neighboring rivers (Kaoping River, Tungkang River, and Lingbeng River) in southwestern Taiwan, Republic of China. Multivariate statistical analysis techniques, i.e., factor analysis, cluster analysis, and canonical discriminant analysis were used for the evaluation of spatial variations to determine the types of pollution and to identify pollutant sources from neighboring rivers. Factor analysis results showed that the most important latent factors in Dapeng Bay are soil texture, heavy metals, organic matter, and nutrients factors. Contour maps incorporating the factor scores showed heavy metals accumulate along the lakesides, especially on the southeastern banks of the lakes. A cluster analysis was performed using factor scores computed from these latent factors. We then classified these areas into five distinct classes using sampling stations, and we illustrate that in the three river classes, the sediment properties are influenced by industrial and domestic wastewater and agricultural activities (including livestock rearing and farm activities). However, in Dapeng Bay, the rivers were influenced more by complicated biogeochemical processes; these could be identified as a type of pollution. Canonical discriminant analysis illustrated that two constructed discriminant functions made a marked contribution to most of the discriminant variables, and the significant parameters of porosity and Cd, Cr, Al, and Pb content were combined as the ??heavy metal factor??. The recognition capacities of the two discriminant functions were 82.6% and 17.4%, respectively. It is also likely that the annual mean of the water exchange rate is insufficient (taking about 7 days to eliminate pollutants) and therefore has significantly influenced the carbon and nutrient biogeochemical processes and budgets in the semi-enclosed ecosystem. Thus, the sediment properties are not similar between the lagoon and the neighboring rivers. Our results yield useful information concerning estuary recovery and water resources management and may be applicable to other basins with similar characteristics that are experiencing similar coastal environmental issues. 相似文献
116.
Averrhoa carambola L., a high-biomass tropical tree, has recently been shown to be a strong accumulator of cadmium (Cd) and has great potential for Cd phytoextraction. In the present study, field studies and a controlled-environment experiment were combined to establish the extent of variation in Cd tolerance and accumulation at the cultivar level using 14 to 19 cultivars of A. carambola. The results indicated that all cultivars tested could accumulate Cd at high but different levels, and that Cd tolerance also varied greatly between these cultivars. It is confirmed that the high Cd tolerance and accumulation capacity are species-level and constitutional traits in A. carambola. However, no correlation was detected between tolerance index and accumulation of Cd in different cultivars, suggesting that the two traits are independent in this woody Cd accumulator. More importantly, cultivar Wuchuan Sweet (WCT) was shown to have the highest Cd-extraction potential; it yielded a high shoot biomass of 30 t ha(-1) in 230 d, and extracted 330 g ha(-1) Cd in the aerial tissues grown in Cd-contaminated field soil, which accounted for 12.8% of the total soil Cd in the top 20 cm of the soil profile. 相似文献
117.
Water Quality during Development and Apportionment of Pollution from Rivers in Tapeng Lagoon, Taiwan
This work investigated water samples collected from Tapeng Lagoon, Taiwan. Factor analysis was conducted to explain the characteristics and the variation in the quality of water during the disassembly of oyster frames and fishery boxes. The result shows that the most important latent factors in Tapeng Lagoon are the ocean factor, primary productivity factor, and the fishery pollution factor. Canonical discriminant analysis is applied to identify the source of pollution in neighboring rivers outside Tapeng Lagoon. The two constructed discriminant functions (CDFs) showed markedly contribution to all discriminant variables, and that total nitrogen, algae, dissolved oxygen and total phosphate, combined in the nutrient effect factor. The recognition capacities in these two CDFs were 95.6%, 4.4%, respectively. The water quality in the Kaoping river most strongly determined that in the Tapeng Lagoon the best is. And disassembling the oyster frames and fishery boxes improves the water quality markedly. However, environmental topographic conditions indicate that strengthening stream pollution prevention and to constructing another entrance to the ocean are the best approaches for improving the quality of water in Tapeng Lagoon, especially by reducing eutrophication. These approaches and results yield useful information concerning habitat recovery and water resource management. 相似文献
118.
A mixed-integer programming model that minimizes the social abatement cost is used to investigate whether a market equilibrium
condition could be reached in a newly proposed permit-trading market for nitrogen oxide control in Taiwan. Unlike in previous
studies, unit pollution abatement cost is determined endogenously by incorporating technology adoption as a binary decision
variable. The results show that when technologies are lumpy and irreversible, disequilibrium might occur due to firms’ inability
to manage their emission levels after installing equipment with fixed size and control capacity.
相似文献
Chao-ning LiaoEmail: |
119.
Yang SX Li JT Yang B Liao B Zhang JT Shu WS 《Journal of environmental monitoring : JEM》2011,13(7):1876-1883
Previous studies have shown that the application of soil amendments is efficient in reducing acidity and heavy metal bioavailability in mine soils. However, it remains a challenge for environmentalists to predict accurately and control economically the re-acidification in re-vegetated mine soils. In this study, net acid generation (NAG) test and bioassay technique were employed to assess the effectiveness of the amendments [including lime, N-P-K (nitrogen, phosphorous and potassium) fertilizer, phosphate and river sediment] on re-acidification and heavy metal immobilization in an extremely acid (pH < 3) mine soil. Our results suggested that NAG test was a rapid and accurate approach to assess the effectiveness of the amendments on re-acidification potential of the mine soil. Interestingly, it was found that phosphate and river sediment played quite specific roles in preventing the re-acidification in the mine soil. In addition, the results also indicated that the addition of 25 t ha(-1) lime combined with river sediment (30%) might be an economical method to successfully control the acidification and re-acidification in the extremely acid mine soil, allowing the re-establishment of the plants. Collectively, our results implied that the combined use of NAG test and bioassay assessment was effective in evaluating a reclamation strategy for extremely acidic mine soils. 相似文献
120.