全文获取类型
收费全文 | 1002篇 |
免费 | 5篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 16篇 |
废物处理 | 21篇 |
环保管理 | 137篇 |
综合类 | 328篇 |
基础理论 | 188篇 |
污染及防治 | 229篇 |
评价与监测 | 50篇 |
社会与环境 | 33篇 |
灾害及防治 | 8篇 |
出版年
2020年 | 9篇 |
2018年 | 18篇 |
2017年 | 13篇 |
2016年 | 16篇 |
2015年 | 16篇 |
2014年 | 23篇 |
2013年 | 72篇 |
2012年 | 26篇 |
2011年 | 36篇 |
2010年 | 27篇 |
2009年 | 23篇 |
2008年 | 37篇 |
2007年 | 44篇 |
2006年 | 26篇 |
2005年 | 25篇 |
2004年 | 38篇 |
2003年 | 21篇 |
2002年 | 25篇 |
2001年 | 18篇 |
2000年 | 17篇 |
1999年 | 19篇 |
1998年 | 8篇 |
1997年 | 14篇 |
1996年 | 21篇 |
1995年 | 18篇 |
1994年 | 30篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 7篇 |
1990年 | 10篇 |
1988年 | 7篇 |
1985年 | 7篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 11篇 |
1980年 | 9篇 |
1979年 | 9篇 |
1978年 | 7篇 |
1977年 | 7篇 |
1973年 | 7篇 |
1964年 | 12篇 |
1963年 | 10篇 |
1961年 | 8篇 |
1960年 | 12篇 |
1959年 | 11篇 |
1957年 | 9篇 |
1956年 | 14篇 |
1954年 | 10篇 |
1939年 | 6篇 |
1924年 | 7篇 |
排序方式: 共有1010条查询结果,搜索用时 203 毫秒
471.
Assessing the impact of the Indian Ocean tsunami on households: a modified domestic assets index approach 总被引:1,自引:0,他引:1
Sudha Arlikatti Walter Gillis Peacock Carla S. Prater Himanshu Grover Arul S. Gnana Sekar 《Disasters》2010,34(3):705-731
This paper offers a potential measurement solution for assessing disaster impacts and subsequent recovery at the household level by using a modified domestic assets index (MDAI) approach. Assessment of the utility of the domestic assets index first proposed by Bates, Killian and Peacock (1984) has been confined to earthquake areas in the Americas and southern Europe. This paper modifies and extends the approach to the Indian sub‐continent and to coastal surge hazards utilizing data collected from 1,000 households impacted by the Indian Ocean tsunami (2004) in the Nagapattinam district of south‐eastern India. The analyses suggest that the MDAI scale is a reliable and valid measure of household living conditions and is useful in assessing disaster impacts and tracking recovery efforts over time. It can facilitate longitudinal studies, encourage cross‐cultural, cross‐national comparisons of disaster impacts and inform national and international donors of the itemized monetary losses from disasters at the household level. 相似文献
472.
Ariel G. Spanowicz Fernanda Zimmermann Teixeira Jochen A. G. Jaeger 《Conservation biology》2020,34(5):1210-1220
Mortality of animals on roads is a critical threat to many wildlife populations and is poised to increase strongly because of ongoing and planned road construction. If these new roads cannot be avoided, effective mitigation measures will be necessary to stop biodiversity decline. Fencing along roads effectively reduces roadkill and is often used in combination with wildlife passages. Because fencing the entire road is not always possible due to financial constraints, high-frequency roadkill areas are often identified to inform the placement of fencing. We devised an adaptive fence-implementation plan to prioritize road sections for fencing. In this framework, areas along roads of high, moderate, and low levels of animal mortality (respectively, roadkill hotspots, warmspots, and coldspots) are identified at multiple scales (i.e., in circles of different diameters [200–2000 m] in which mortality frequency is measured). Fence deployment is based on the relationship between the amount of fencing being added to the road, starting with the strongest roadkill hotspots, and potential reduction in road mortality (displayed in mortality-reduction graphs). We applied our approach to empirical and simulated spatial patterns of wildlife–vehicle collisions. The scale used for analysis affected the number and spatial extent of roadkill hot-, warm-, and coldspots. At fine scales (e.g., 200 m), more hotspots were identified than at coarse scales (e.g., 2000 m), but combined the fine-scale hotspots covered less road and less fencing was needed to reduce road mortality. However, many short fences may be less effective in practice due to a fence-end effect (i.e., animals moving around the fence more easily), resulting in a trade-off between few long and many short fences, which we call the FLOMS (few-long-or-many-short) fences trade-off. Thresholds in the mortality-reduction graphs occurred for some roadkill patterns, but not for others. Thresholds may be useful to consider when determining road-mitigation targets. The existence of thresholds at multiple scales and the FLOMS trade-off have important implications for biodiversity conservation. 相似文献
473.
474.
Mohammad S. Farhadinia Paul J. Johnson Alexandra Zimmermann Philip J.K. McGowan Erik Meijaard Mark Stanley-Price David W. Macdonald 《Conservation biology》2020,34(4):988-996
The persistence of endangered species may depend on the fate of a very small number of individual animals. In situ conservation alone may sometimes be insufficient. In these instances, the International Union for Conservation of Nature provides guidelines for ex situ conservation and the Convention on Biological Diversity (CBD) indicates how ex situ management can support the CBD's objectives by providing insurance policies for species. The circumstances that justify its use are uncertain. To evaluate the current in situ extinction risk and ex situ management of 43 critically endangered species of mammalian megafauna, we used nonmetric multidimensional scaling and geopolitical variables related to governance, economics, and national policy within their extant ranges. We then fitted generalized additive models to assess the contribution of each variable to the ordination. Fifteen (almost one-third) of the world's terrestrial mammalian megafauna are not the subject of any ex situ management. Seventy-three percent of these taxa occur in areas characterized by political uncertainty, such as border zones or areas affected by armed conflicts, mainly in Africa and the Middle East. A further 23% of taxa in ex situ programs do not meet sustainability criteria for inbreeding avoidance. Strategic conservation planning, such as the One Plan approach, may improve ex situ management for these taxa. Given the escalating trend in threats afflicting megafauna, ex situ management should be considered more rigorously, particularly in politically unstable regions, to achieve CBD Target 12 (prevent extinction of threatened species). 相似文献
475.
Understanding the climate and its variability, in particular with regard to their socioeconomic impact, requires specific
measurements of precipitation and temperature and their circulations. This becomes more important in applications to diverse
systems. In order to improve knowledge about temporal changes and trends in temperature, we analyzed series of maximum and
minimum daily surface temperatures at eight reference stations in southeastern South America during variable periods, with
the longest periods of around 100 years. To study the evolution of the temperature series and to reduce the number of parameters,
a nonhierarchical cluster analysis was performed. The algorithm assigns each day to one of four groups: warm, wet, cold and
dry. Low frequency variations were found in these groups and their association with circulation structure, circulation patterns
and precipitation. We concluded that the set of wet days is one of the main factors driving secular variations of maximum
and minimum temperature and variations in precipitation. We also inferred that after 1920 till 1930, a low frequency oscillation
is observed in the form of linear trends (increase of warm days and decrease of cold days). 相似文献
476.
Christophe Walgraeve Kristof Demeestere Jo Dewulf Ralf Zimmermann Herman Van Langenhove 《Atmospheric environment (Oxford, England : 1994)》2010,44(15):1831-1846
Particulate matter (PM) has become a major research issue receiving increasing attention because of its significant negative impact on human health. There are main indicators that next to the morphological characteristics of the particle, also the chemical composition plays an important role in the adverse health effects of PM. In this context, the rather polar organic fraction of PM is expected to play a major role, and advanced analytical techniques are developed to improve the knowledge on the molecular composition of this fraction. One component class that deserves major attention consists of the oxygenated polycyclic aromatic hydrocarbons (PAHs). Those compounds are considered to be among the key compounds in PM toxicity. This paper presents a comprehensive review focusing on the analysis, fate and behavior of oxygenated PAHs in the atmosphere. The first part of the paper briefly introduces (i) the main sources and atmospheric pathways of oxygenated PAHs, (ii) available physical–chemical properties and (iii) their health effects. The second and main part of this paper gives a thorough discussion on the entire analytical sequence necessary to identify and quantify oxygenated PAHs on atmospheric PM. Special attention is given to critical parameters and innovations related to (i) sampling, (ii) sample preparation including both extraction and clean-up, and (iii) separation and detection. Third, the state-of-the-art knowledge about the atmospheric occurrence of oxygenated PAHs is discussed, including an extended overview of reported concentrations presented as a function of sampling season and geographical location. A clear seasonal effect is observed with the median of the oxygenated PAHs concentrations during winter being a factor of 3–4 higher than during summer. However, the oxygenated PAH/parent PAH ratio is about 20 times higher during summer, indicating the importance of photochemical activity in the atmosphere. 相似文献
477.
478.
Dario Cristina P. Piva Alex Zattera Ademir J. Roman Celso Angioletto Elídio Zimmermann Matheus V. G. 《Journal of Material Cycles and Waste Management》2022,24(6):2216-2228
Journal of Material Cycles and Waste Management - In recent years, the use of residue for the production of new composite materials has gained prominence as it enables reuse of materials and... 相似文献
479.
Vigni Lorenza Li Daskalopoulou Kyriaki Calabrese Sergio Kyriakopoulos Konstantinos Parello Francesco Brugnone Filippo D’Alessandro Walter 《Environmental geochemistry and health》2022,44(7):2111-2133
Environmental Geochemistry and Health - Geothermal areas of Greece are located in regions affected by recent volcanism and in continental basins characterised by elevated heat flow. Many of them... 相似文献
480.
Chlorine position of chlorophenol isomers has a significant effect on the dechlorination kinetics of monochlorophenols, dichlorophenols, and trichlorophenols during Fenton oxidation. The effects have been evaluated by the rate constants of the dechlorination kinetic model developed in this study. It is found that the dechlorination rate of 3-CP is faster than that of 4-CP, which is faster than that of 2-CP. Since OH and Cl groups on the aromatic ring are ortho and para directors, the directory effect of OH and Cl groups enhances the dechlorination kinetics of 2-CP due to acceleration of the hydroxylation of 2-CP. Therefore, the dechlorination kinetics increases accordingly. For trichlorophenols (TCP), steric hindrance plays an important role during their dechlorination process. Specifically, the closer the chlorine atoms locate with each other on the aromatic ring, the more difficult the dechlorination processes will be. The dechlorination kinetics of dichlorophenols seems to be affected by both directory effect of OH and Cl groups and the effect of steric hindrance of chlorine atoms. The directory effect of OH and Cl groups on trichlorophenols decreases since the chlorine atom occupied the positions which are the most favorable for hydroxyl radical attack. 相似文献