全文获取类型
收费全文 | 285篇 |
免费 | 11篇 |
国内免费 | 82篇 |
专业分类
安全科学 | 28篇 |
废物处理 | 13篇 |
环保管理 | 16篇 |
综合类 | 191篇 |
基础理论 | 37篇 |
污染及防治 | 60篇 |
评价与监测 | 33篇 |
出版年
2023年 | 12篇 |
2022年 | 3篇 |
2021年 | 15篇 |
2020年 | 21篇 |
2019年 | 11篇 |
2018年 | 13篇 |
2017年 | 16篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 13篇 |
2013年 | 30篇 |
2012年 | 22篇 |
2011年 | 23篇 |
2010年 | 13篇 |
2009年 | 15篇 |
2008年 | 23篇 |
2007年 | 19篇 |
2006年 | 25篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 5篇 |
2001年 | 9篇 |
2000年 | 10篇 |
1999年 | 7篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有378条查询结果,搜索用时 15 毫秒
31.
Tanu Jindal Dileep K. Singh H. C. Agarwal 《Journal of environmental science and health. Part. B》2013,48(4):367-372
This study was undertaken to determine the dissipation and degradation of coumaphos [O-(3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7-yl) O,O-diethyl phosphorothioate] under different sunlight conditions and at different temperatures. The effect of the ultra violet (UV) component of solar radiation was also studied using quartz tubes in addition to other radiation in the visible range using glass tubes and the results were compared with those obtained under the dark light conditions. Water suspensions of coumaphos were incubated at three temperatures viz. 22°C, 37°C and 53°C in closed systems to study the effect of temperature. Volatilization, mineralization and degradation of coumaphos increased with an increase in temperature and exposure to solar radiation, particularly under the UV component of the solar radiation. Major loss of the pesticide occurred through volatilization. The optimum temperature for the degradation of coumaphos was found to be at 37°C. The data obtained from the mineralization and degradation studies indicated that 53°C crosses the biological range for suitable growth of microorganism. UV radiation exposure along with maintaining temperature at 37°C may prove useful in the dissipation and/or degradation of coumaphos prior to its disposal as waste from cattle dipping vats. 相似文献
32.
Sarina Saltzman Lilian Kliger 《Journal of environmental science and health. Part. B》2013,48(4):353-366
Abstract The volatilization of DBCP from soils, as affected by the soil characteristics and application techniques, was studied in a laboratory experiment. The volatilization rate of DBCP applied in water was higher from sandy and silty loam soils than from clay soil. Water added after DBCP application acted as a soil cover, decreasing the volatilization rate. The results obtained with DBCP application in hexane to air‐dry soils, indicate that adsorption could be an important factor in reducing the volatilization losses. Diffusion coefficients were calculated from the volatilization parameters, by using a simplified relationship between volatilization losses and diffusion through soil. 相似文献
33.
《Journal of environmental science and health. Part. B》2013,48(2):363-374
Phosphorus recovery from greenhouse wastewater, using precipitation-crystallization, was conducted under three levels of calcium concentration, 304 mg/L (7.6 mmol/L), 384 mg/L (9.6 mmol/L), and 480 mg/L (12 mmol/L), and also with additions of ammonium and magnesium into the wastewater. Jar test results confirmed high phosphate removal, with more than 90% of the removal achieved with a pH as low as 7.7. Under the low calcium concentration, ammonium addition affected the chemical reactions at pH lower than 8.0, where struvite was produced; when the pH was raised to 8.8, other calcium compounds dominated the precipitation. Under the medium calcium concentration, ammonium and magnesium addition helped struvite precipitation in the low pH range. Hydroxyapatite (HAP) was the main product. Under the high calcium concentration, ammonium addition showed no effects on the precipitation. 相似文献
34.
基于Berthollet反应示波极谱法测定水中微量氨 总被引:1,自引:0,他引:1
在亚硝基铁氰化钾存在下,氨在氢氧化钠介质中与苯酚、次氯酸钠反应,其产物靛酚在滴汞电极上产生-灵敏的吸附波,NH3-N在0.003~0.22mg/L内,导数峰电流与其呈良好的线性关系。用于环境水中NH3-N的测定,其相对标准偏差小于3%,回收率为97%~105%,方法具有较好的选择性。 相似文献
35.
博物馆室内微环境中碱性气体的被动采样方法研究 总被引:3,自引:1,他引:2
针对博物馆微环境中的碱性污染气体-氨气,采用自行研制的被动采样器,建立了一套适合博物馆馆藏文物保存环境中氨气含量分析的被动采样-离子色谱检测方法,应用于博物馆的实地采样分析,通过与主动法采样对照,获得了被动采样器在博物馆微环境中氨的吸收系数,从而获得采样点空气中氨气的浓度,为博物馆文物保存环境监测提供了可行方法。 相似文献
36.
分析HACH氨氮自动监测分析仪所用进口试剂配方中氧化剂、显色剂、催化剂、掩蔽剂、缓冲液的组分、试剂用量、反应机理、吸收光谱、酸碱度、发色时间和温度、显色产物的稳定性、灵敏度、干扰及消除,以及存放条件的差异,自行研发国产配方,并将该国产配方试剂与进口试剂做试验比对,结果 2种试剂的效能无显著差异。 相似文献
37.
38.
Using water curtain system to forced mitigate ammonia vapor cloud has been proven to be an effective measure. Currently, no engineering guidelines for designing an effective water curtain system are available, due to lack of understanding of complex interactions between ammonia vapor cloud and water droplets, especially the understanding of ammonia absorption into water droplets. This paper presents numerical calculations to reproduce the continuous ammonia release dispersion with and without the mitigating influence of a downwind water curtain using computational fluid dynamic (CFD) software ANSYS Fluent 14.0. The turbulence models k–ɛ and RNG were used to simulate the ammonia cloud dispersion without downwind water curtain. The simulated results were compared with literature using the statistical performance indicators. The RNG model represents better agreement with the experimental data and the k–ɛ model generates a slightly lesser result. The RNG model coupled with Lagrangian discrete phase model (DPM) was used to simulate the dilution effectiveness of the water curtain system. The ammonia absorption was taken into account by means of user-defined functions (UDF). The simulated effectiveness of water curtains has good agreements with the experimental results. The effectiveness of water mitigation system with and without the ammonia absorption was compared. The results display that the effectiveness mainly depends on the strong air entrainment enhanced by water droplets movement and the ammonia absorption also enhances the effectiveness of water curtain mitigation system. The study indicates that the CFD code can be satisfactorily applied in design criteria for an effective mitigation system. 相似文献
39.
Anjana Pant 《The Environmentalist》2000,20(4):295-300
Nostoc calcicola cells exposed to mercuric chloride (0.05–0.25 M), methyl mercuric chloride (0.05–0.15 M) and the fungicide ceresan (phenyl mercuric acetate; 0.05–0.20 M) showed sensitivity in the sequence: methyl mercury3) over phenyl mercuric acetate (0.51×103); inorganic mercury occupied the intermediate position with a bioconcentration factor of 1.32×103. The data infer that larger molecules of organomercurials may not be taken up by cells at the rate and extent comparable to the smaller species. 相似文献
40.
A nonstationary time-series model is used to examine the changes occurring at sampling stations on the Chicago Sanitary and Ship Canal. Using data from upstream sampling sites, downstream levels of dissolved oxygen, total dissolved solids, nitrates and nitrites, and ammonia are accurately predicted. The method is simple, insensitive to extreme values, and responsive to changes in the system. 相似文献