全文获取类型
收费全文 | 130篇 |
免费 | 9篇 |
国内免费 | 35篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 22篇 |
环保管理 | 8篇 |
综合类 | 82篇 |
基础理论 | 25篇 |
污染及防治 | 15篇 |
评价与监测 | 17篇 |
社会与环境 | 2篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2019年 | 3篇 |
2017年 | 1篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 3篇 |
2012年 | 7篇 |
2011年 | 6篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 6篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 13篇 |
2004年 | 10篇 |
2003年 | 5篇 |
2002年 | 13篇 |
2001年 | 11篇 |
2000年 | 7篇 |
1999年 | 9篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 1篇 |
排序方式: 共有174条查询结果,搜索用时 31 毫秒
41.
应用油松针叶监测大气二氧化硫污染 总被引:2,自引:0,他引:2
蒋高明 《城市环境与城市生态》1995,8(1):19-22
承德市油松针叶中硫与大气SO2浓度之间存在着很显著的相关性(r=0.7841,P<0.01),利用这一相关性对承德市区42个采样点大气SO2污染状况进行了生物监测,并绘制了城市大气SO2污染分布图,基本符合承德市大气SO2分布规律。 相似文献
42.
Jesper Heile Christensen 《Atmospheric environment (Oxford, England : 1994)》1997,31(24):4169-4191
A three-dimensional Eulerian hemispheric air pollution model, the Danish Eulerian Hemispheric Model (DEHM), is in development at the National Environmental Research Institute (NERI). The model has been used to study long-range transport of air pollution in the Northern Hemisphere. The present version of the model includes long-range transport of sulphur dioxide (SO2) and particulate sulphate (SC42−. The chemistry in the model is described by a simple linear oxidation of SO2 to SO42−, and the wet deposition of SO2 and SO4− is estimated based on the amount of precipitation, which is calculated from the contents of liquid cloud water (see Christensen, Air Pollution Modelling and its Applicatioons, Vol. X, pp. 119–127, Vol. XI, pp. 249–256, Plenum press, New York; 1995, Ph.D. thesis, National Environmental Research Institute, Denmark). The model has been used to study the air pollution in the Arctic. Results from yr simulation with an analysis of the results is presented: the model results are verified by comparisons, to measurements not only from the Arctic region but also from Europe and Canada. Some examples of episodes in the Arctic including analysis of the meteorological conditions during the episodes are presented. Finally, the model has been used to estimate the contribution from the different source regions on the northern hemisphere to the Arctic sulphur pollution. 相似文献
43.
Background, Aims and Scope Secondary inorganic aerosol (SIA), i.e. particulate sulphate (S(VI)), ammonium and nitrate (N(V)) is formed from gaseous
precursors i.e., sulfur dioxide (S(IV)), ammonia and nitrogen oxides, in polluted air on the time-scale of hours to days.
Besides particulate ammonium and nitrate, the respective gaseous species ammonia and nitric acid can be formed, too. SIA contributes
significantly to elevated levels of respirable particulate matter in urban areas and in strongly anthropogenically influenced
air in general.
Methods The near-ground aerosol chemical composition was studied at two stationary sites in the vicinity of Berlin during a field
campaign in summer 1998. By means of analysis of the wind field, two episodes were identified which allow to study changes
within individual air masses during transport i.e., a Lagrangian type of experiment, with one station being upwind and the
other downwind of the city. By reference to a passive tracer (Na+) and estimates on dry depositional losses, the influences
of dispersion and mixing on concentration changes can be eliminated from the data analysis.
Results and Discussion Chemical changes in N(-III), N(V) and S(VI) species were observed. SIA i.e., N(V) and S(VI), was formed from emissions in
the city within a few hours. The significance of emissions in the city was furthermore confirmed by missing SIA formation
in the case of transport around the city. For the two episodes, SIA formation rates could be derived, albeit not more precise
than by an order of magnitude. N(V) formation rates were between 1.4 and 20 and between 1.9 and 59 % h-1 on the two days,
respectively, and S(VI) formation rates were > 17 and > 10 % h-1. The area south of the city was identified as a source of
ammonia.
Conclusion The probability of occurrence of situations during which the downwind site (50 km downwind of Berlin) would be hit by an
urban plume is > 7.4%. Furthermore, for the general case of rural areas in Germany it is estimated that for more than half
of these there is a significant probability to be hit by an urban plume (> 8%). The S(VI) formation rates are higher than
explainable by homogeneous gas-phase chemistry and suggest the involvement of heterogeneous reactions of aerosol particles.
Recommendation and Outlook The possible contribution of heterogeneous processes to S(VI) formation should be addressed in laboratory studies. Measurements
at more than two sites could improve the potential of Lagrangian field experiments for the quantification of atmospheric chemical
transformations, if a second downwind site is chosen in such a way that, at least under particular stability conditions, measurements
there are representative for the source area. 相似文献
44.
钛基燃烧催化剂的抗硫性能 总被引:1,自引:0,他引:1
本文研究了钛基非贵金属燃烧催化剂的硫中毒过程及载体吸硫特性。结果表明,催化剂的抗硫能力与载体吸硫量有关,不同催化剂的抗硫性能为:Cat.3>Cat.4>Cat.5>Cat.1>Cat.2,本文还讨论了硫中毒机理。 相似文献
45.
Alfred J. Vella Alex Camilleri Jean Pierre Tabone Adami 《Environmental geochemistry and health》1996,18(4):165-170
The concentration of sulphate on limestone surfaces of the external walls of churches in Malta is shown to be related to their position and distance from a power station, the main local point source of sulphur dioxide pollution. Limestone powder collected from these surfaces was examined for the presence of particles which, under low-power optical microscopy, appear as shiny black amorphous bodies which were interpreted as soot particles; the abundance of these bodies was expressed as a black particle count (BPC). The degree of sulphation and BPC were shown to be correlated with each other and both appeared to be strongly dependent on the prevailing wind. The BPC contour map indicated an important contribution to the parameter from vehicular traffic. It is suggested that the degree of sulphation and BPC of limestone surfaces from the built environment should function as environmental indicators of the relative air quality with respect to SO2 and soot pollution. This data is possibly more accurately representative of the relative long-term air-quality status of different areas of habitation than that deduced from single or episodic measurements of atmospheric pollutant levels. 相似文献
46.
47.
对SOx、NOx的存在形态进行了热力学与化学平衡计算,据此提出了监测技术改进的建议。对工程检测、在线连续监测及大气污染物排放量的统计,也提出了初步的设想。 相似文献
48.
硫/石灰石滤柱的自养反硝化动力学模型 总被引:1,自引:0,他引:1
本文对用硫作为电子供体,硝酸盐作为电子受体,由脱氮硫杆菌进行的自养反硝化过程的动力学模型进行了研究。结果表明,硝酸盐在滤料表面生物膜中的扩散过程对硫/石灰石滤柱的反硝化动力学影响很大。若扩散速率慢,硝酸盐只能穿过生物膜的一部分,则滤柱的反硝化速率遵循1/2级反应动力学;若扩散速率快,硝酸盐能穿过整个生物膜,则滤柱的反硝化速率遵循零级反应动力学。 相似文献
49.
针对国内硫磺回收装置实际生产中存在的设备腐蚀问题,根据不同的腐蚀机理进行了腐蚀分类,分析了腐蚀原因并提出了具体的防护措施. 相似文献
50.