全文获取类型
收费全文 | 520篇 |
免费 | 6篇 |
国内免费 | 10篇 |
专业分类
安全科学 | 29篇 |
废物处理 | 13篇 |
环保管理 | 104篇 |
综合类 | 85篇 |
基础理论 | 120篇 |
污染及防治 | 109篇 |
评价与监测 | 55篇 |
社会与环境 | 19篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 2篇 |
2022年 | 10篇 |
2021年 | 7篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 10篇 |
2017年 | 13篇 |
2016年 | 22篇 |
2015年 | 11篇 |
2014年 | 24篇 |
2013年 | 45篇 |
2012年 | 40篇 |
2011年 | 37篇 |
2010年 | 13篇 |
2009年 | 25篇 |
2008年 | 35篇 |
2007年 | 22篇 |
2006年 | 33篇 |
2005年 | 21篇 |
2004年 | 21篇 |
2003年 | 22篇 |
2002年 | 16篇 |
2001年 | 1篇 |
2000年 | 8篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 6篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1978年 | 2篇 |
1977年 | 2篇 |
排序方式: 共有536条查询结果,搜索用时 31 毫秒
501.
Patricia Brierley Newell 《Journal of environmental psychology》1998,18(4):357-371
As a further step in developing a systems model of privacy, variables involved in the process of achieving a condition of privacy were examined cross-culturally. Subjects were students from Ireland, Senegal and the United States. Striking commonalities were found in the reasons why subjects required privacy, the affect that was associated with a desire for privacy, the definition of privacy as a condition of the person, the duration of the average privacy experience and the change in affect at the completion of the experience which supported the suggestion that privacy has a therapeutic effect. Within culture, variability was associated with age, gender and in the case of Senegal, with income. Between culture, variability was hardly noticeable. The majority of the subjects in each culture believed that not being disturbed was the most important element of privacy and grief, fatigue and need to focus were the main affective sets associated with seeking privacy. It is believed that several universals have been identified which may be used in later research, and that the study supports a systems-based model of privacy. 相似文献
502.
Patricia Miretzky Carolina Muñoz Alejandro Carrillo-Chávez 《Environmental Chemistry Letters》2007,5(3):131-136
The Pb (II) adsorption/desorption mechanism onto a natural sandy loam soil was studied by batch experiments at different pHs
(3.0, 4.5, 6.0), at different ionic strength (0, 0.02 and 0.1 M) and with different electrolytes solutions of NaCl, NaAcO
and NaNO3. Pb was strongly adsorbed onto the soil due to the formation of a mix of inner-sphere and outer-sphere complexes. Experimental
adsorption data fitted Freundlich and Langmuir isotherms. The desorption results with 0.1 M Mg (NO3)2 and 0.1 M NaAcO solutions corroborated the mechanisms proposed. The strong binding of Pb (II) to high affinity sites on soil
minerals seems to be responsible for the extent of hysteresis. The sandy loam soil under study thus constitutes a natural
control for Pb contamination. 相似文献
503.
504.
We consider the extent to which the Mackenzie Valley Resource Management Act (MVRMA) provides an opportunity for deliberative democracy to emerge within the context of resource management in Canada's North. The focus is on the extent to which the tenets of deliberative democracy are exercised in the environmental assessment (EA) of the Snap Lake diamonds project. Data collection included semi-structured interviews with assessment participants, and a review of documentation surrounding the EA process, and the case study. Results combined four principles of deliberative democracy: generality, autonomy, power neutrality, and ideal role taking. The EA conducted under the MVRMA can serve as a deliberative process, as illustrated by opportunities for dialogue, access to different perspectives, and learning outcomes. However, many of these positive results occurred through nonmandated technical sessions. The absence of participant funding also limits the deliberative potential of the MVRMA. 相似文献
505.
506.
507.
508.
509.
The spiny lobster, Panulirus argus, is predominantly nocturnal, remaining inside shelters during the day and foraging outside at night, presumably to minimize
predation risk. Predation risk generally decreases with increasing lobster size. Therefore, this study examined the hypothesis
that size would influence this basic circadian pattern. Video cameras continuously recorded the shelter occupancy of juvenile
lobsters (n = 72) having a carapace length (CL) of 30–62 mm that were tethered to shelters in a shallow reef lagoon. The lobsters’ shelter
occupancy was 100% during the day, but declined linearly from shortly before sunset to a minimum of 50% shortly after midnight
and then increased linearly, reaching 100% by 1 h after sunrise. The percent time the lobsters spent in the shelters followed
a similar trend, but there was wide variability at night (0–100%) for individual lobsters. Lobsters left their shelters 2–30
times night−1, with a majority of excursions lasting <10 min. These results suggest that juvenile P. argus minimize predation risk by remaining in their shelters as long as possible but offset the energetic cost of this behavior
by foraging close to their shelters for several short periods at night. This emergence pattern contrasts with those of early
benthic phase lobsters (<15 mm CL), which seldom leave their shelters, and adults (>80 mm CL), which have a dusk/early evening
peak in activity and leave the shelter for extended periods of time during the night. Furthermore, a minimum shelter occupancy
in the middle of the night appears especially well adapted to avoid exposure to daytime predators. Videotaped observations
also included interactions between lobsters and two dominant lobster predators, the triggerfish, Balistes capriscus, and the octopus Octopus cf. vulgaris. Lobsters responded differently to these predators: remaining in the shelter when attacked by a triggerfish and fleeing the
shelter when attacked by an octopus. Triggerfish were nearly twice as likely to attack a lobster that was outside of the shelter
than inside. Once under attack, however, a lobster had nearly the same chance of surviving if it was inside or outside. Results
suggest that the patterns of shelter use and emergence change as lobsters grow, probably reflecting the interplay between
perception of predation risk and the need to forage.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
510.
Olivier Monga Mamadou Bousso Patricia Garnier Valrie Pot 《Ecological modelling》2008,216(3-4):291-302
During the past 10 years, soil scientists have started to use 3D Computed Tomography in order to gain a clearer understanding of the geometry of soil structure and its relationships with soil properties. We propose a geometric model for the 3D representation of pore space and a practical method for its computation. Our basic idea consists in representing pore space using a minimal set of maximal balls (Delaunay spheres) recovering the shape skeleton. In this representation, each ball could be considered as a maximal local cavity corresponding to the “intuitive” notion of a pore as described in the literature. The space segmentation induced by the network of balls (pores) was then used to spatialize biological dynamics. Organic matter and microbial decomposers were distributed within the balls (pores). A valuated graph representing the pore network, organic matter and distribution of micro-organisms was then defined. Microbial soil organic matter decomposition was simulated by updating this valuated graph. The method was implemented and tested using real CT images. The model produced realistic simulated results when compared with data in the literature in terms of the water retention curve and carbon mineralization. A decrease in water pressure decreased carbon mineralization, which is also in accordance with findings in the literature. From our results we showed that the influence of water pressure on decomposition is a function of organic matter distribution in the pore space. As far as we know, this is the approach to have linked pore space geometry and biological dynamics in a formal way. Our next goal will be to compare the model with experimental data of decomposition using different soil structures, and to define geometric typologies of pore space shape that can be attached to specific biological and dynamic properties. 相似文献