全文获取类型
收费全文 | 297篇 |
免费 | 3篇 |
国内免费 | 11篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 5篇 |
环保管理 | 47篇 |
综合类 | 130篇 |
基础理论 | 32篇 |
污染及防治 | 63篇 |
评价与监测 | 6篇 |
社会与环境 | 13篇 |
灾害及防治 | 1篇 |
出版年
2022年 | 3篇 |
2021年 | 3篇 |
2020年 | 5篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2014年 | 3篇 |
2013年 | 31篇 |
2012年 | 3篇 |
2011年 | 18篇 |
2010年 | 7篇 |
2008年 | 5篇 |
2007年 | 13篇 |
2006年 | 12篇 |
2005年 | 9篇 |
2004年 | 12篇 |
2003年 | 8篇 |
2002年 | 18篇 |
2001年 | 4篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1980年 | 6篇 |
1978年 | 2篇 |
1975年 | 3篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1969年 | 4篇 |
1967年 | 3篇 |
1966年 | 3篇 |
1965年 | 3篇 |
1963年 | 4篇 |
1962年 | 9篇 |
1961年 | 3篇 |
1960年 | 5篇 |
1959年 | 6篇 |
1958年 | 4篇 |
1957年 | 8篇 |
1956年 | 4篇 |
1955年 | 3篇 |
1933年 | 2篇 |
1932年 | 3篇 |
1923年 | 2篇 |
排序方式: 共有311条查询结果,搜索用时 31 毫秒
1.
2.
Review on the annual PM10 concentrations over a 10-year period shows that Macau is subjected to severe fine particulate pollution. Investigations of its variation in monthly and daily time scales with the local meteorological records reveal further details. It is found that a distinct feature of the Asian monsoon climates, the changes of wind direction, mainly controls the general trend of PM10 concentration in a year. The monsoon driven winter north-easterly winds bring upon Macau dry and particle enriched air masses leading to a higher concentration in that period while the summer south-westerly winds transport humid and cleaner air to the region leading to a lower PM10 value. This distinct seasonal feature is further enhanced by the lower rainfall volume and frequency as well as mixing height in winter and their higher counterparts in summer. It is also found that the development of tropical cyclones near Macau could also impose episode like PM10 concentration spikes due to the pre-typhoon induced stagnant air motion followed by the swing of wind direction to the northerly. 相似文献
3.
Kriech AJ Osborn LV Wissel HL Kurek JT Sweeney BJ Peregrine CJ 《Journal of environmental monitoring : JEM》2004,6(10):827-833
Exposure to asphalt fumes has a threshold limit value (TLV of 0.5 mg m(-3) (benzene extractable inhalable particulate) as recommended by the American Conference of Governmental Industrial Hygienists (ACGIH). This reflects a recent change (2000) whereby two variables are different from the previous recommendation. First is a 10-fold reduction in quantity from 5 mg m(-3) to 0.5 mg m(-3). Secondly, the new TLV specifies the "inhalable" fraction as compared to what is presumed to be total particulate. To assess the impact of these changes, this study compares the differences between measurements of paving asphalt fume exposure in the field using an "inhalable" instrument versus the historically used 'total' sampler. Particle size is also examined to assist in the understanding of the aerodynamic collection differences as related to asphalt fumes and confounders. Results show that when exposures are limited to asphalt fumes, a 1:1 relationship exists between samplers, showing no statistically significant differences in benzene soluble matter (BSM). This means that for the asphalt fume ACGIH TLV, the 'total' 37-mm sampler is an equivalent method to the "inhalable" method, referred to as IOM (Institute of Occupational Medicine), and should be acceptable for use against the TLV. However, the study found that when confounders (dust or old asphalt millings) are present in the workplace, there can be significant differences between the two samplers' reported exposure. The ratio of IOM/Total was 1.37 for milling asphalt sites, 1.41 for asphalt paving over granular base, and 1.02 for asphalt over asphalt pavements. 相似文献
4.
5.
6.
Herbert H. Koepf 《Agriculture, ecosystems & environment》1984,11(3):268-270
7.
8.
Alan B. Bolten Peter Feinsinger Herbert G. Baker Irene Baker 《Die Naturwissenschaften》1990,77(9):452-452
9.
10.