全文获取类型
收费全文 | 572篇 |
免费 | 25篇 |
国内免费 | 197篇 |
专业分类
安全科学 | 44篇 |
废物处理 | 32篇 |
环保管理 | 31篇 |
综合类 | 311篇 |
基础理论 | 81篇 |
污染及防治 | 218篇 |
评价与监测 | 20篇 |
社会与环境 | 25篇 |
灾害及防治 | 32篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 33篇 |
2021年 | 22篇 |
2020年 | 21篇 |
2019年 | 10篇 |
2018年 | 20篇 |
2017年 | 27篇 |
2016年 | 19篇 |
2015年 | 30篇 |
2014年 | 28篇 |
2013年 | 45篇 |
2012年 | 40篇 |
2011年 | 55篇 |
2010年 | 39篇 |
2009年 | 35篇 |
2008年 | 49篇 |
2007年 | 45篇 |
2006年 | 35篇 |
2005年 | 23篇 |
2004年 | 21篇 |
2003年 | 23篇 |
2002年 | 17篇 |
2001年 | 24篇 |
2000年 | 17篇 |
1999年 | 18篇 |
1998年 | 17篇 |
1997年 | 15篇 |
1996年 | 6篇 |
1995年 | 13篇 |
1994年 | 6篇 |
1993年 | 7篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有794条查询结果,搜索用时 31 毫秒
581.
582.
Liu F Ni HG Chen F Luo ZX Shen H Liu L Wu P 《Environmental monitoring and assessment》2012,184(7):4289-4299
Mining effluents are the main source of metals in the surrounding aquatic environment. The mining district of Purple Mountain has a history of copper mining for more than 30 years, but there is limited investigation of metal bioaccumulation in the aquatic creatures from the Tingjiang river catchment affected by the mining activities. In this study, we collected grass carps (Ctenopharyngodon idellus) from four sites, and analyzed the accumulation of chromium (Cr), nickel (Ni), manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) in ten tissues (scale, skin, muscle, gill, liver, kidney, fish maw, heart, stomach, and intestine) of the fish samples. Among all tissue samples, the highest concentrations (micrograms per gram wet weight) of Ni (0.263), Cu (69.2), Zn (84.0), As (0.259), Cd (0.640), Hg (0.051), and Pb (0.534) were noted in the liver, gill, and kidney tissues, whereas the highest concentrations of Cr (0.356) and Mn (62.7) were detected in the skin and intestine, respectively. These results gave a better understanding of the variability of metals distribution in different fish tissues. In comparison with the sample sites, metals (especially Mn, Cu, Zn, Ni, and Pb) in liver, gill, kidney, stomach, and intestine showed more inter-site differences than other tissues. The inter-site differences also revealed that site 1 and 2 increased fish uptake of Cu, Zn, Ni, and Pb, which may indicate that the copper mine and urban effluents contributed to high levels of these metals in aquatic environments in site 1 and 2. A potential food safety issue may emerge depending on the mining activities in this region because some metals in a few tissue samples exceeded the guideline values for human consumption of fish. 相似文献
583.
Fengyu Gao Hao Yan Xiaolong Tang Honghong Yi Shunzheng Zhao Qingjun Yu Shuquan Ni 《环境科学学报(英文版)》2021,33(3):36-48
Cu-Co multiple-oxides modified on HNO3-pretreated activated coke (ACN) were optimized for the simultaneous removal of gaseous CO and elemental mercury (Hg0) at low temperature (< 200 °C). It was found that 2%CuOx-10%CoOx/ACN catalyst calcined at 400°C resulted in the coexistence of complex oxides including CuO, Cu2O, Co3O4, Co2O3 and CoO phases, which might be good for the simultaneous catalytic oxidation of CO by Co-species and removal of Hg0 by Cu-species, benefiting from the synergistic catalysis during the electro-interaction between Co and Cu cations (CoO ? Co3O4 and Cu2O ? CuO). The catalysis removal of CO oxidation was obviously depended on the reaction temperature obtaining 94.7% at 200 °C, while no obvious promoting effect on the Hg0 removal (68.3%-78.7%). These materials were very substitute for the removal of CO and Hg° from the flue gas with the conditions of 8–20 vol.% O2 and flue-gas temperature below 200 °C. The removal of Hg° followed the combination processes of adsorption and catalytic oxidation reaction via Langmuir-Hinshelwood mechanism, while the catalysis of CO abided by the Mars-van Krevelen mechanism with lattice oxygen species. 相似文献
584.
Fanhao Meng Min Qin Wu Fang Jun Duan Ke Tang Helu Zhang Dou Shao Zhitang Liao Yan Feng Yong Huang Ting Ni Pinhua Xie Jianguo Liu Wenqing Liu 《环境科学学报(英文版)》2022,34(4):297-307
To investigate nitrous acid(HONO) levels and potential HONO sources above crop rotation fields. The HONO fluxes were measured by the aerodynamic gradient(AG) method from 14 December 2019 to 2 January 2020 over an agricultural field in the Huaihe River Basin. The ambient HONO levels were measured at two different heights(0.15 and 1.5 m), showing a typical diurnal cycle with low daytime levels and high nighttime levels. The upward HONO fluxes were mostly observed during the day, whereas deposition... 相似文献
585.
通过对活性污泥不同抑制情况下呼吸速率变化的分析,对不同的抑制类型提出了利用呼吸速率确定抑制动力学模型中动力学常数的不同方法.产物抑制通过已知起始浓度和呼吸速率曲线,来构建以1/K'P为斜率,KS为截距的直线方程来求解KS和抑制常数.底物抑制先通过呼吸速率求解最值点的底物浓度,然后根据呼吸速率变化最大值点的关系公式求解抑制常数的方法.竞争性抑制和非竞争性抑制通过求解等速点底物浓度的方法求解抑制常数.对于非竞争性抑制还可以通过简单的最大呼吸速率比值法来求解抑制常数.同时选择非竞争性抑制进行了试验验证和常数求解.最终通过2种方法得到葡萄糖降解时NaCl的抑制常数为20.2 g/L,或者0.02倍的KS. 相似文献
586.
Gasification characteristics of MSW and an ANN prediction model 总被引:1,自引:0,他引:1
Xiao G Ni MJ Chi Y Jin BS Xiao R Zhong ZP Huang YJ 《Waste management (New York, N.Y.)》2009,29(1):240-244
Gasification characteristics make up the important parts of municipal solid waste (MSW) gasification and melting technology. These characteristics are closely related to the composition of MSW, which alters with climates and seasons. It is important to find a practical way to predict gasification characteristics. In this paper, five typical kinds of organic components (wood, paper, kitchen garbage, plastic, and textile) and three representative types of simulated MSW are gasified in a fluidized-bed at 400-800 degrees C with the equivalence ratio (ER) in the range of 0.2-0.6. The lower heating value (LHV) of gas, gasification products, and gas yield are reported. The results indicate that gasification characteristics are different from sample to sample. Based on the experimental data, an artificial neural networks (ANN) model is developed to predict gasification characteristics. The training and validating relative errors are within +/-15% and +/-20%, respectively, and predicting relative errors of an industrial sample are below +/-25%. This indicates that it is acceptable to predict gasification characteristics via ANN model. 相似文献
587.
Optimizing the operating parameters to minimize polychlorodibenzo-p-dioxins and polychlorodibenzofurans (PCDD/F) emission is the common interest of the municipal solid waste (MSW) incineration industry. In this study, we investigated the distribution of tetra- to octa-CDD/F along the flue gas line in a full-scale reciprocating grate incinerator and evaluated the effects of temperature control and O(2) level on PCDD/F formation. Six runs were laid out and all performed under sufficient burning conditions, in which the combustion efficiency of MSW was more than 99.9%. The total concentration of tetra- to octa-CDD/F measured at the boiler outlet showed an increasing tendency with the increase of boiler outlet temperature (T(B)) from 214 degrees C to 264 degrees C. When flue gas ran across the semi-dry scrubber and cyclone precipitator, in which the temperature varied from 264 degrees C to 162 degrees C, the concentrations of the lower chlorinated dioxins and furans were significantly raised, especially for the TCDF. Increasing O(2) supply from 6.0% to 10.5% essentially led to a higher yield of tetra- to octa-PCDD/F, suggested that under sufficient burning conditions the lower O(2) level was favorable for reducing PCDD/F formation and emission. The variation of O(2) level did not give rise to a systematical change of PCDD/F homologue pattern. For all measurements, the isomer distributions of tetra- to hepta-PCDD/F were more or less the same, nearly independent of variations in the operating conditions and sampling positions. Only the significant increase of the sum of 1,3,7,8-TCDF and 1,3,7,9-TCDF was found in the zone after the boiler section. 相似文献
588.
Hong-Gang Ni Ru-Lang Shen Eddy Y. Zeng 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3502-3507
The mass emissions of linear alkylbenzenes (LABs), benzothiazole (BT), and 2-[4-morpholinyl]benzothiazole (24MoBT) from anthropogenic activities within one year were estimated according to the population and the number of automobiles in the Pearl River Delta (PRD), South China. Based on the estimation, the distribution of these compounds among various environmental media was simulated with a mass balance box model established in the present study. The results showed that 79% of LABs generated in the PRD was stored in sediment while only 1.3% of LABs was presumably transported to the adjacent South China Sea (SCS). On the contrary, 47% of BT and 77% of 24MoBT generated in the region were carried with riverine runoff to the coastal ocean. The results from the present study suggest that hydrophobic compounds tend to stay in the watershed of the PRD, whereas hydrophilic ones mainly outflow to the coastal ocean. 相似文献
589.
Pei-Hsuan Kuo Pei-Chen Ni Andrew Keats Ben-Jei Tsuang Yung-Yao Lan Min-Der Lin Chien-Lung Chen Yueh-Yuan Tu Len-Fu Chang Ken-Hui Chang 《Atmospheric environment (Oxford, England : 1994)》2009,43(25):3925-3934
In 1995, Taiwan's Environmental Protection Administration (EPA/TW) instituted a policy of levying emission taxes on polluters in order to combat the rampant national issue of pollution. Since that time, pollution control strategies, tightening exhaust emission standards for industry, improvements in fuel quality, and new stricter vehicle emission standards, etc., have been implemented. This study evaluates the effectiveness of these measures and examines the improvement of Taiwan's air quality. In this paper, we conduct a detailed analysis of change in the concentrations of pollutants (SO2, NOx and particulate matter [PM]) between two three-year periods (from 1996 to1998 and from 2000 to 2002). The pollution levels were generally lower in the latter period. Concentrations at 14 EPA/TW stations in central Taiwan were simulated and source apportionment analyses in three of Central Taiwan's largest cities were conducted using a trajectory transfer-coefficient air quality model. Correlation coefficients (r) between simulations and observations for the monthly means of the concentrations of SO2, NOx, PM2.5 and PM10 during the study periods at the 14 stations are 0.56, 0.63, 0.70 and 0.31, respectively. The sulfur control policy greatly reduced SO2 concentration island-wide, a stringent emission standard put into place for gasoline vehicles reduced NOx concentration along highways, and an emissions tax placed on construction sites, as well as a regular program for road-dust sweeping, reduced primary particulate matter. Among all of the pollution abatement policies implemented, the most effective method for reducing PM2.5 concentrations in the three largest cities involved the reduction of fine ammonium sulfate aerosols from point sources (56–63% of net PM2.5 reduction). The next largest reduction was attributed to a diminishment in primary PM2.5 emanating from point sources (27–56% of net PM2.5 reduction). Secondary particulate matter, especially sulfate, was reduced from distances up to 150 km leeward of major pollution point sources such as Taichung Power Plant. 相似文献
590.