全文获取类型
收费全文 | 776篇 |
免费 | 29篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 26篇 |
废物处理 | 32篇 |
环保管理 | 193篇 |
综合类 | 54篇 |
基础理论 | 198篇 |
环境理论 | 2篇 |
污染及防治 | 238篇 |
评价与监测 | 36篇 |
社会与环境 | 24篇 |
灾害及防治 | 6篇 |
出版年
2023年 | 7篇 |
2022年 | 8篇 |
2021年 | 6篇 |
2020年 | 10篇 |
2019年 | 10篇 |
2018年 | 19篇 |
2017年 | 18篇 |
2016年 | 16篇 |
2015年 | 13篇 |
2014年 | 14篇 |
2013年 | 84篇 |
2012年 | 21篇 |
2011年 | 30篇 |
2010年 | 27篇 |
2009年 | 31篇 |
2008年 | 35篇 |
2007年 | 44篇 |
2006年 | 45篇 |
2005年 | 25篇 |
2004年 | 22篇 |
2003年 | 21篇 |
2002年 | 19篇 |
2001年 | 16篇 |
2000年 | 11篇 |
1999年 | 14篇 |
1998年 | 11篇 |
1997年 | 22篇 |
1996年 | 12篇 |
1995年 | 10篇 |
1994年 | 13篇 |
1993年 | 9篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 9篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 14篇 |
1984年 | 14篇 |
1983年 | 12篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1978年 | 6篇 |
1977年 | 7篇 |
1976年 | 11篇 |
1974年 | 7篇 |
1970年 | 3篇 |
1969年 | 3篇 |
排序方式: 共有809条查询结果,搜索用时 17 毫秒
31.
The Efficacy of a Programme of Landslide Risk Reduction in Areas of Unplanned Housing in the Eastern Caribbean 总被引:1,自引:0,他引:1
Malcolm G. Anderson Elizabeth Holcombe Maricarmen Esquivel Joaquin Toro Francis Ghesquiere 《Environmental management》2010,45(4):807-821
Poor countries are disproportionately affected by the cost of disasters. Yet there is evidence of the benefits of seeking
to mitigate the impact of a disaster, compared with the costs incurred in ‘making good’ after a major event has occurred.
This article reviews a programme of landslide risk reduction in unplanned communities in the Eastern Caribbean. The construction
of appropriate surface water management measures, based on the application of scientific and engineering principles, has been
demonstrated to reduce the hazard from rainfall-triggered landslides. Adopting a community-based approach additionally delivers
social and environmental benefits relating to employment generation, improvements in the environmental conditions within the
community, and improvements slope management practices. The sustained implementation of the community-based projects has provided
the necessary evidence-base for these practices to influence Government policy and practice, and gain recognition from regional
development agencies. The strategic and incremental uptake of the community-based methodology is demonstrated to be an effective
means for delivering physical landslide risk reduction measures in the most ‘at risk’ areas of unplanned housing. 相似文献
32.
O.R.J. Anderson R.A. Phillips R.A.R. McGill S. Bearhop 《Environmental pollution (Barking, Essex : 1987)》2010,158(1):98-107
We investigated the concentrations of 22 essential and non-essential elements among a community of Procellariiformes (and their prey) to identify the extent to which trophic position and foraging range governed element accumulation. Stable isotope analysis (SIA) was used to characterise trophic (δ15N) and spatial patterns (δ13C) among species. Few consistent patterns were observed in element distributions among species and diet appeared to be highly influential in some instances. Arsenic levels in seabird red blood cells correlated with δ15N and δ13C, demonstrating the importance of trophic position and foraging range for arsenic distribution. Arsenic concentrations in prey varied significantly across taxa, and in the strength of association with δ15N values (trophic level). In most instances, element patterns in Procellariiformes showed the clearest separation among species, indicating that a combination of prey selection and other complex species-specific characteristics (e.g. moult patterns) were generally more important determining factors than trophic level per se. 相似文献
33.
Luca Coscieme Federico M. Pulselli Simone Bastianoni Christopher D. Elvidge Sharolyn Anderson Paul C. Sutton 《Ambio》2014,43(7):969-979
Night-time satellite imagery enables the measurement, visualization, and mapping of energy consumption in an area. In this paper, an index of the “sum of lights” as observed by night-time satellite imagery within national boundaries is compared with the emergy of the nations. Emergy is a measure of the solar energy equivalent used, directly or indirectly, to support the processes that characterize the economic activity in a country. Emergy has renewable and non-renewable components. Our results show that the non-renewable component of national emergy use is positively correlated with night-time satellite imagery. This relationship can be used to produce emergy density maps which enable the incorporation of spatially explicit representations of emergy in geographic information systems. The region of Abruzzo (Italy) is used to demonstrate this relationship as a spatially disaggregate case. 相似文献
34.
35.
V. Withstandley W.J. Moroz G.W. Anderson 《Journal of the Air & Waste Management Association (1995)》2013,63(9):571-573
A portable, battery-operated, electro-optical dust analyzer operating on the principle of light scattering from individual dust particles in air drawn through a high-intensity light field has been developed for monitoring dust levels where external power may be unavailable. The instrument counts and size-discriminates airborne particles over two size ranges upwards of 0.3 microns with immediate readout. A dilution mechanism permits analysis of particulate concentrations as high as 2400 particles/cm3 on each channel. The self-contained Ni-Cd batteries are rechargeable. Total weight, including batteries and all components, is approximately 14 Ib. Total power used, mainly for pumping a filtered air sheath at 300 cm/sec and for the light source, is less than 34 watts. Another unique feature is the flow system designed for turbulence suppression. Electronic calibration in terms of number of particles/cm3 for each size range is accomplished in the laboratory by means of a pulse generator with respect to which the readout indicator is calibrated for count. The input voltages to the pulse-height discriminators are appropriately attenuated for various pulse amplitudes simulating the output of the light-sensitive pickup, a photomultiplier tube.Pulse height as a function of particle size was measured for polystyrene latex beads ranging from 0.3 to 2 microns in diameter. Good correlation is obtained with results from commercial analyzers. Field surveys have been undertaken with the CAES prototype analyzer at various sites in central Pennsylvania and at numerous sampling points within the cities of Pittsburgh and Philadelphia. Particulate concentrations as high as 1400 particles/ cm3 have been measured at a coal cleaning plant. 相似文献
36.
A Wind Tunnel Study of Gaseous Pollutants in City Street Canyons 总被引:1,自引:0,他引:1
James B. Wedding David J. Lombardi Jack E. Cermak 《Journal of the Air & Waste Management Association (1995)》2013,63(6):557-566
Steady state mean concentrations of tracer gas were measured in a 400:1 scale model of an idealized city with variable geometry placed within a wind tunnel at various orientations to the mean flow for a free stream velocity of 6.8 ft/sec. The tracer gas was released from two parallel line sources to simulate lanes of traffic in an effort to quantify the persistence of pollution as well as the mean values realized at street levels. An aerodynamically rough turbulent boundary layer of neutral thermal stratification was employed to simulate the atmosphere. Values of concentration measured in the model city were converted to prototype concentrations in ppm and compared to National Ambient Air Quality Standards. It was shown that single isolated structures may cause favorable mixing of pollution downwind but very high concentrations exist in the immediate leeward vicinity of the building. Two favorable geometries for city blocks tested were found to reduce pedestrian exposure to pollution both near heavy traffic congestion and downwind. It was concluded that the pollutant dilution was controlled by the mean flow rather than by turbulent diffusion and that the lateral spread of the plume was slight as one proceeded downwind of the line source. The combination of favorable geometry and higher dilution velocities may bring pollution levels down to existing Air Quality Standards. The body of information presented in this paper should interest city planners and air quality monitoring personnel, as well as those researchers attempting to study and model flow in city street canyons. It provides order of magnitude estimates on pedestrian and office worker exposure to pollutants under a wide range of conditions. 相似文献
37.
Edward L. Avol Leonard H. Wightman William S. Linn Jack D. Hackney 《Journal of the Air & Waste Management Association (1995)》2013,63(7):743-745
The cause of the Yokkaichi asthma episode (1960-1969) has been analyzed. It Is concluded that the respiratory diseases were due not to sulfur dioxide but to concentrated sulfuric acid mists emitted from stacks of calciners of a titanium oxide manufacturing plant located windward of the residential area. 相似文献
38.
Larry G. Anderson 《Journal of the Air & Waste Management Association (1995)》2013,63(9):970-973
It has been recognized for several years that ozone in rural areas can exceed the National Ambient Air Quality Standard (NAAQS) for photochemical oxidant whirh was 0.08 ppm for one hour, not to be exceeded more than once per year. During the summer of 1973, the NAAQS was exceeded from 15 to 37% of the time at four rural monitoring sites in Maryland, Pennsylvania, Ohio, and West Virginia.1 This is a greater violation rate than is found in many urban areas. Dimitriades and Altshuller2 have enumerated four possible sources for this rural ozone: (a) transport from urban areas, (b) local photochemical generation from urban ozone precursors, (c) local photochemical generation from precursors of rural origin which may be man-made or natural, and (d) injection of stratospheric ozone into the rural area. This paper considers the chemistry pertinent to the first two of these possible sources of rural ozone, namely the long distance (overnight) transport of ozone and ozone precursors. 相似文献
39.
40.