全文获取类型
收费全文 | 781篇 |
免费 | 2篇 |
国内免费 | 6篇 |
专业分类
安全科学 | 24篇 |
废物处理 | 16篇 |
环保管理 | 241篇 |
综合类 | 60篇 |
基础理论 | 144篇 |
污染及防治 | 224篇 |
评价与监测 | 60篇 |
社会与环境 | 16篇 |
灾害及防治 | 4篇 |
出版年
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 6篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 15篇 |
2015年 | 6篇 |
2014年 | 5篇 |
2013年 | 104篇 |
2012年 | 18篇 |
2011年 | 26篇 |
2010年 | 26篇 |
2009年 | 24篇 |
2008年 | 36篇 |
2007年 | 37篇 |
2006年 | 43篇 |
2005年 | 22篇 |
2004年 | 34篇 |
2003年 | 29篇 |
2002年 | 32篇 |
2001年 | 12篇 |
2000年 | 20篇 |
1999年 | 8篇 |
1998年 | 14篇 |
1997年 | 17篇 |
1996年 | 13篇 |
1995年 | 14篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 11篇 |
1991年 | 12篇 |
1990年 | 5篇 |
1989年 | 12篇 |
1988年 | 8篇 |
1987年 | 10篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 17篇 |
1983年 | 14篇 |
1982年 | 9篇 |
1981年 | 14篇 |
1980年 | 3篇 |
1979年 | 14篇 |
1978年 | 8篇 |
1976年 | 8篇 |
1975年 | 5篇 |
1974年 | 4篇 |
1972年 | 5篇 |
1971年 | 4篇 |
1970年 | 4篇 |
排序方式: 共有789条查询结果,搜索用时 31 毫秒
51.
Katrine A. Gorham Nicola J. Blake Richard A. VanCuren Henry E. Fuelberg Simone Meinardi Donald R. Blake 《Atmospheric environment (Oxford, England : 1994)》2010,44(19):2271-2279
We present a study of the seasonal and diurnal variability of carbon monoxide and selected volatile organic compounds in the Los Angeles area. Measurements were made during four different nine-day field campaigns in April/May, September, and November, 2007, and February, 2008, at the Mt. Wilson sampling site, which is located at an elevation of approximately 1700 m in the San Gabriel Mountains overlooking Pasadena and the Los Angeles basin. The results were used to characterize the Mt. Wilson site as a representative location for monitoring integrated Los Angeles basin emissions, and, by reference to carbon monoxide emissions, to estimate average annual emissions. The considerable seasonal variability of many hydrocarbons, in both their measured mixing ratios and their relationship to carbon monoxide, was indicative of variable source strengths. Most interestingly, perturbation of C4 hydrocarbon ratios suggested an enhanced role for chlorine chemistry during the month of September, likely as the result of Los Angeles’ coastal location. Such coastal influence was confirmed by observations of enhanced mixing ratios of marine halocarbons, as well as air mass back trajectories. 相似文献
52.
Pierre Mineau Kanth M.S. Sundaram Alam Sundaram Cecilia Feng Donald G. Busby Peter A. Pearce 《Journal of environmental science and health. Part. B》2013,48(1):105-135
Abstract Four test groups of small songbirds (Zebra Finch, Poephila guttata) were sprayed in a chamber with varying concentrations of fenitrothion. Exposure levels were assessed by monitoring air concentrations, deposits of the active ingredient (AI) on glass plates and droplets/cm2 on Kromekote® cards. All indices of exposure were linearly correlated and the mean AI deposit on glass plates for the four groups tested were equivalent to 38, 51, 139 and 255 g/ha or 14%, 18%, 50% and 91% of the highest permissible emitted rate for broadscale forest spraying in Canada. Significant depression in body weights and brain acetylcholinesterase levels were noted only for the highest exposure group. Fenitrothion residues in blood were detectable only at the highest exposure level, and in liver at the two higher levels. Carcass and feather residues were much higher than those in blood and liver, and were detectable at all exposure levels but the residues did not increase linearly with exposure. For one of the spray groups, we were able to compute an equivalent acute oral dose based on matching acetylcholinesterase inhibition. 相似文献
53.
54.
55.
56.
Donald S. Shepard 《Journal of the Air & Waste Management Association (1995)》2013,63(11):756-761
Load-shifting, a relatively inexpensive approach to air pollution control, involves transferring the generating load from one power plant to another according to meteorological conditions. In this paper, an atmospheric dispersion model is adapted to estimate the exposure of the urban population to sulfur dioxide from operating the power system in different ways. Then a mathematical model of the power system of a metropolitan area is constructed to determine the reduction in pollution exposure which could be achieved, and the costs involved. As a case study, the application of the model to St. Louis, Missouri, is simulated. Under favorable conditions, load shifting could reduce pollution exposure up to 95%, while increasing the costs of electric power generation by only 4%. The load-shifting model has use not only as an operational control strategy, but also as an analytical tool to evaluate alternative pollution control measures in the electric power industry. 相似文献
57.
Donald E. Seizinger Basil Dimitriades 《Journal of the Air & Waste Management Association (1995)》2013,63(1):47-51
Photochemical air pollution is known to be caused largely by automotive emissions such as hydrocarbons and oxygenated hydrocarbon derivatives. Unlike the hydrocarbons, the contribution of the oxygenates has been virtually unexplored, mainly because of lack of appropriate analytical methods. The objective of this study was to identify and estimate the levels of oxygenated hydrocarbon derivatives in exhaust from simple hydrocarbon fuels. This information is expected to yield ultimately estimates of the relative levels of various classes of oxygenates in exhaust from full-boiling-range gasolines. Identification and measurement of oxygenates in exhaust from the simplified fuels were accomplished using gas chromatography in conjunction with time-of-flight mass spectrometry. The analytical procedure involved concentration of the exhaust organics, followed by a two-stage chromatographic separation of the resultant mixture of oxygenates and hydrocarbons. Identified oxygenates in exhaust from nine test fuels included saturated and unsaturated aldehydes, ketones, and alcohols, as well as ethers, esters, and nitroalkanes; analytical data on organic acids were inconclusive. Of the identified noncarbonyl oxygenates, phenols, cyclic ethers and nitromethane appear to be relatively the most abundant. 相似文献
58.
Donald G. Gillette 《Journal of the Air & Waste Management Association (1995)》2013,63(4):329-331
The body of information presented in this paper is directed to policy makers and administrators involved in the evaluation and assessment of damages caused by oxidant air pollution on human health and welfare and of possible benefits of control. To provide a comparison of some of the benefits that can be obtained by reducing photochemical oxidant levels, estimated health costs were derived from data relating adverse health effects to hourly oxidant concentrations. Hourly oxidant or ozone concentrations were measured at approximately 400 monitoring stations scattered throughout the U.S. Most of these sites were located in major urban areas or in other areas where high oxidant concentrations prevailed. Estimates of populations at risk and per capita health costs were generated for those areas where oxidant data was available. During the period 1971-1973, nearly two-thirds of the U.S. population resided in areas where the hourly primary standard for oxidants of 160 µg/m3 was exceeded. The total annual health cost attributable to oxidants was estimated to range from $120 to over $240 million in the U.S. 相似文献
59.
Thomas J. Kulle Larry R. Sauder J. Richard Hebel Donald J. Green Marie D. Chatham 《Journal of the Air & Waste Management Association (1995)》2013,63(8):919-924
Industrial, commercial, and domestic levels of formaldehyde exposure range from <0.1 to >5.0 ppm. Irritation of the eyes and upper respiratory tract predominate, and bronchoconstriction is described in case reports. However, pulmonary function and irritant symptoms together have not been assessed over a range of HCHO concentrations in a controlled environment. We investigated dose response in both symptoms and pulmonary function associated with 3-h exposures to 0.0-3.0 ppm HCHO in a controlled environmental chamber. Ten subjects were randomly exposed to 0.0, 0.5, 1.0, and 2.0 ppm HCHO at rest plus 2.0 ppm HCHO with exercise and nine additional subjects were randomly exposed to 0.0,1.0,2.0, and 3.0 ppm HCHO at rest plus 2.0 ppm HCHO with exercise. Significant dose-response relationships in odor and eye irritation were observed (p < 0.05). Nasal flow resistance was increased at 3.0 ppm (p < 0.01), but not at 2.0 ppm HCHO. There were no significant decrements in pulmonary function (FVC, FEV1, FEF25-75%, SGaw) or increases in bronchial reactivity to methacholine (log PD35SGaw) with exposure to 0.5-3.0 ppm HCHO at rest or to 2.0 ppm HCHO with exercise. 相似文献
60.
Bernacchi CJ Leakey AD Kimball BA Ort DR 《Environmental pollution (Barking, Essex : 1987)》2011,159(6):1464-1472
Tropospheric ozone is increasing in many agricultural regions resulting in decreased stomatal conductance and overall biomass of sensitive crop species. These physiological effects of ozone forecast changes in evapotranspiration and thus in the terrestrial hydrological cycle, particularly in intercontinental interiors. Soybean plots were fumigated with ozone to achieve concentrations above ambient levels over five growing seasons in open-air field conditions. Mean season increases in ozone concentrations ([O3]) varied between growing seasons from 22 to 37% above background concentrations. The objective of this experiment was to examine the effects of future [O3] on crop ecosystem energy fluxes and water use. Elevated [O3] caused decreases in canopy evapotranspiration resulting in decreased water use by as much as 15% in high ozone years and decreased soil water removal. In addition, ozone treatment resulted in increased sensible heat flux in all years indicative of day-time increase in canopy temperature of up to 0.7 °C. 相似文献