全文获取类型
收费全文 | 247篇 |
免费 | 4篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 10篇 |
废物处理 | 11篇 |
环保管理 | 20篇 |
综合类 | 62篇 |
基础理论 | 74篇 |
环境理论 | 1篇 |
污染及防治 | 52篇 |
评价与监测 | 12篇 |
社会与环境 | 8篇 |
灾害及防治 | 2篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 9篇 |
2017年 | 4篇 |
2016年 | 10篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 18篇 |
2012年 | 9篇 |
2011年 | 14篇 |
2010年 | 15篇 |
2009年 | 14篇 |
2008年 | 12篇 |
2007年 | 14篇 |
2006年 | 19篇 |
2005年 | 9篇 |
2004年 | 5篇 |
2003年 | 18篇 |
2002年 | 2篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1965年 | 1篇 |
1923年 | 3篇 |
排序方式: 共有252条查询结果,搜索用时 15 毫秒
141.
Peter Jacques 《Journal of Environmental Planning and Management》2006,49(2):301-307
High resolution climate models of regions, or downscaling, promises to be at the forefront of future climate policy research. However, most research in this area is in the natural sciences, and the policy community has not taken full notice of this trend at their doorstep. Downscaling provides more concrete information about local impacts of climate change. This raises several important political issues surrounding extreme events, adaptation, risk and equity and legacy concerns, all of which are briefly addressed. The paper concludes with a call for more social science research on downscaling to accompany the rich geophysical science literature in the topic. 相似文献
142.
Dry tomb and bioreactor landfills were analyzed with respect to their external costs in an intergenerational cost-benefit analysis in a partial framework which enabled a sounder comparison to be carried out between these two technologies from a socio-economic viewpoint. Obviously, this approach was only a first step for building a comprehensive basis of any environmental as well as fiscal policy in the field of waste management. All external costs are identified and evaluated in three different scenarios, corresponding to a worst case, a best guess and a best case. Obviously, discounting is crucial with respect to an intergenerational perspective. Generation-adjusted discounting (GAD) was applied to take into account equity as well as efficiency criteria, in order to deal with three different types of uncertainties that are decisive in waste policy decisions: a physical uncertainty is captured by introducing our three different scenarios; a macroeconomic uncertainty is taken into consideration by calculating present values using different real growth rates; and a microeconomic uncertainty is taken into account by considering individual peculiarities reflected in their subjective time preference rate. The findings show, that whenever there is a low real GDP growth of less than 1%, the bioreactor is generally superior to the dry tomb (lower present values of external costs). This statement becomes more valid as the growth rate decreases. However, whenever there are high positive growth rates, it is the dry tomb technology which is superior to the bioreactor system. 相似文献
143.
144.
145.
146.
147.
148.
The photochemical behaviour of chlorophenols is different to that of non-halogenated phenols. In the former, the first step is a C-Cl bond scission, which is not influenced by oxygen. Chlorine is converted into hydrochloric acid. For monochlorophenols, the position of the chlorine on the ring strongly influences the transformation. In the molecular form, 2-chlorophenol is converted into pyrocatechol. In the anionic form however, it is reduced in a cyclopentadienic acid which dimerizes according to a Diels-Alder reaction. The irradiation of 3-chlorophenol leads to resorcinol whatever the pH. This would appear to suggest a photohydrolysis mechanism. With 4-chlorophenol, the photochemical conversion is not so specific. Hydroquinone is formed (mainly in aerated solution), along with polyphenolic oligomers. A radical mechanism is proposed. 相似文献
149.
150.
Squirrels include several independent lineages of dwarf forms distributed into two ecological groups: the dwarf tree and flying
squirrels. The mandible of dwarf tree squirrels share a highly reduced coronoid process and a condylar process drawn backwards.
Dwarf flying squirrels on the other hand, have an elongated coronoid process and a well-differentiated condylar process. To
interpret such a difference, Elliptic Fourier Transform was used to evaluate how mandible shape varies with dwarfism in sciurids.
The results obtained show that this clear-cut difference cannot be explained by a simple allometric relationship in relation
with size decrease. We concluded that the retention of anteriorly positioned eye sockets, in relation with distance estimation,
allowed the conservation of a well-differentiated coronoid process in all flying species, despite the trend towards its reduction
observed among sciurids as their size decreases.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献