全文获取类型
收费全文 | 52篇 |
免费 | 0篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 3篇 |
环保管理 | 3篇 |
综合类 | 30篇 |
基础理论 | 5篇 |
污染及防治 | 5篇 |
评价与监测 | 2篇 |
社会与环境 | 1篇 |
出版年
2017年 | 1篇 |
2016年 | 1篇 |
2014年 | 1篇 |
2013年 | 2篇 |
2011年 | 3篇 |
2010年 | 1篇 |
2009年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2003年 | 3篇 |
2000年 | 2篇 |
1998年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1984年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1963年 | 1篇 |
1962年 | 2篇 |
1961年 | 1篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1957年 | 1篇 |
1955年 | 2篇 |
1953年 | 1篇 |
1949年 | 1篇 |
1947年 | 1篇 |
1943年 | 1篇 |
1942年 | 1篇 |
1933年 | 1篇 |
1930年 | 1篇 |
1926年 | 1篇 |
排序方式: 共有52条查询结果,搜索用时 15 毫秒
41.
42.
43.
We describe intercomparison results obtained in the framework of the EC Directive 799/80 CEE on SO2, Black Smoke (BS) and Total Suspended Particulates (TSP) using standard reference materials. Calibrations and measuring methods used in national laboratories were compared to the reference methods laid down in the Directive. For SO2, the deviations were caused by inappropriate handling of the calibration rather than by possible shortcomings of the different methods themselves. In contrast, for BS, largest deviations were caused by differences in configurations of filter/reflectometer and of the conversion curves; for TSP by varying the type of filters and conditioning procedures before weighing. 相似文献
44.
Charlotte Pfeiffer Christoph Emmerling Dietmar Schröder Jürgen Niemeyer 《Environmental Sciences Europe》1998,10(3):147-153
The influence of four synthetic chemicals (nonylphenol, ethynyl-estradiol, ivermectin, monesin) on the biomass and on the microbial activity was studied in a laboratory experiment using a typical luvisol derived from loess. The polyether antibiotic monensin, the antiparasitic agent ivermectin and the two environmental chemicals with endocrine effects nonylphenol and ethynylestradiol were chosen because of their toxicity to different organisms and known biological activity. These agents may enter the soil together with sewage sludge or manure. To date, however, the effects on soil have hardly been studied. Selected microbial methods revealed in part very significant effects on the microbial biomass and microbial activity during constant physical (15°C, 50% water holding capicity) and chemical conditions (pH, Corg) 1, 14 and 42 days after contamination. 相似文献
45.
46.
47.
48.
Temporal variability of soil gas composition in landfill covers 总被引:1,自引:0,他引:1
In order to assess the temporal variability of the conditions for the microbial oxidation of methane in landfill cover soils and their driving variables, gas composition at non-emissive and strongly emissive locations (hotspots) was monitored on a seasonal, daily and hourly time scale on an old, unlined landfill in northern Germany. Our study showed that the impact of the various environmental factors varied with the mode of gas transport and with the time scale considered. At non-emissive sites, governed by diffusive gas transport, soil gas composition was subject to a pronounced seasonal variation. A high extent of aeration, low methane concentrations and a high ratio of CO2 to CH4 were found across the entire depth of the soil cover during the warm and dry period, whereas in the cool and moist period aeration was less and landfill gas migrated further upward. Statistically, variation in soil gas composition was best explained by the variation in soil temperature. At locations dominated by advective gas transport and showing considerable emissions of methane, this pattern was far less pronounced with only little increase in the extent of aeration during drier periods. Here, the change of barometric pressure was found to impact soil gas composition. On a daily scale under constant conditions of temperature, gas transport at both types of locations was strongly impacted by the change in soil moisture. On an hourly scale, under constant conditions of temperature and moisture, gas migration was impacted most by the change in barometric pressure. It was shown that at diffusion-dominated sites complete methane oxidation was achieved even under adverse wintry conditions, whereas at hotspots, even under favorable dry and warm conditions, aerobic biological activity can be limited to the upper crust of the soil. 相似文献
49.
50.