全文获取类型
收费全文 | 145篇 |
免费 | 8篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 5篇 |
废物处理 | 7篇 |
环保管理 | 29篇 |
综合类 | 39篇 |
基础理论 | 34篇 |
污染及防治 | 17篇 |
评价与监测 | 9篇 |
社会与环境 | 39篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 1篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2017年 | 1篇 |
2016年 | 7篇 |
2015年 | 4篇 |
2014年 | 4篇 |
2013年 | 12篇 |
2012年 | 5篇 |
2011年 | 10篇 |
2010年 | 5篇 |
2009年 | 9篇 |
2008年 | 12篇 |
2007年 | 8篇 |
2006年 | 11篇 |
2005年 | 9篇 |
2004年 | 9篇 |
2003年 | 5篇 |
2002年 | 9篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 1篇 |
1998年 | 3篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 7篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1980年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有180条查询结果,搜索用时 0 毫秒
11.
The efficiency of chir pine sawdust (CPS) for adsorptive removal of the dyes, congo red (CR) and basic violet 1 (BV), from aqueous solution was evaluated using batch and column studies. The equilibrium was attained in 60 min for CR and 45 min for BV. The adsorption of BV obeyed the Langmuir isotherm model while the Freundlich isotherm fitted the equilibrium data of CR adsorption. The Langmuir monolayer adsorption capacities (Qo) of CPS for BV and CR were 11.3 and 5.8 g kg?1, respectively. The kinetic data for CR were best fitted to the Lagergren pseudo-first-order model and for BV to the pseudo-second-order model. The intra-particle diffusion was found to be the rate-controlling step for CR adsorption, while the adsorption kinetics of BV were controlled by both intra-particle and liquid-film diffusion. The thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic in nature. The adsorption activation energy (Ea) for CR (124 kJ mol?1) implied chemical adsorption while that for BV (5.4 kJ mol?1) indicated physical adsorption. An increase in the Thomas model constant (KTh) with increasing flow indicated that for both dyes the mass transport resistance decreased during adsorption. Thus, CPS may be an efficient low-cost adsorbent for decolorization of dye-containing wastewaters. 相似文献
12.
N. A. Kalashnik 《Russian Journal of Ecology》2008,39(4):261-271
The level of chromosome aberrations at different stages of mitosis has been studied in the seed sprout meristem of four conifer species growing in the Southern Urals in areas differing in the kind and degree of industrial pollution. The results provide evidence for the adverse effect of pollution on the chromosomal machinery of these species. With respect to environmental quality assessment, the Scots pine is the most sensitive indicator species among conifers growing in the Southern Urals and analysis of chromosome aberrations in anaphase-telophase cells is most effective among the cytogenetic methods tested. 相似文献
13.
Changes in the main climatic factors (air temperature and total precipitation) and their effect on the radial increment of Scots pine (Pinus sylvestris L.) over the period from 1933 to 2002 were studied in an insular pine forest growing in the steppe zone of the Southern Urals. Evidence for a significant increase in the amount of precipitation and air temperature in the second half of this period was obtained. Functions of response of radial increment indices to climatic parameters were analyzed. Relative contributions of air temperature and precipitation to variation in the radial increment of pine in different time intervals proved to differ in relation to climate changes during the past century. 相似文献
14.
S. N. Goroshkevich 《Russian Journal of Ecology》2008,39(3):168-175
A statistical analysis of interannual variation in a set of vegetative and generative characters over 13 years has been performed to characterize the growth and seed production dynamics of the Siberian stone pine (Pinus sibirica Du Tour) in the southeast of the forest zone in western Siberia. The results have shown that the range of fluctuations in most of vegetative characters is ordinary and their distribution is close to normal. The range of fluctuations in many generative characters is enormous (from 0 to +∞), and the distribution of their values is usually skewed, with low values being recorded several times more frequently than high values. Most variable are the proportion of abortive cones and other characters that are determined mainly in the spring of the pollination year. These characters account for a very high level of variation in the total seed production. 相似文献
15.
16.
S. N. Sannikov I. V. Petrova N. S. Sannikova T. V. Filippova 《Russian Journal of Ecology》2005,36(6):377-382
Gradients of Nei's genetic distances between 15 samples of Pinus sylvestris L. trees were analyzed along three submeridional transects, from Scandinavia to the Mediterranean and Transcaucasia. As a result, distinct chorogenetic differentiation was revealed between the populations of this species growing in climatically specific regions of northern and southern Europe. Considerable Nei's distances (DN = 0.045–0.056) and their gradients, combined with differences in stable phenotypic characters (the composition of monoterpenes and morphological parameters of cones) determined at the Pyrenean and Caucasian mountain borders, suggest that the P. sylvestris species structure includes two South Eurasian subspecies, the Pyrenean P. sylvestris L., ssp. iberica Svoboda and the Transcaucasian P. sylvestris L., ssp. hamata (Stev.) Fomin. 相似文献
17.
The dependence of the annual increment of vegetative organs on air temperature and humidity and the amount of precipitation per phenophase, as well as the period of their growth in Scots pine, were studied in the forest-steppe zone of Cisbaikalia. The multiple effect of variation in environmental conditions on the annual increment of organs increased when precipitation in September of the previous year was taken into account. These factors proved to have a stronger effect on variation in the annual increment of needles (R 2 = 0.59, p = 0.00005) than that in the annual ring width (R 2 = 0.38, p = 0.0002). 相似文献
18.
E. A. Kleshcheva 《Russian Journal of Ecology》2007,38(2):94-100
A method for estimating the current state of plant communities based on the ecological amplitudes of constituent species is proposed. An original program, Fitoindikatsiya, has been developed to compute the indices of disturbance and homogeneity of plant communities from species ecological scale values. The current state of pine forests in the part of Novosibirsk oblast east of the Ob River has been analyzed; slightly, moderately, and severely disturbed zones have been distinguished. 相似文献
19.
Morphophysiological and anatomical characters of needles that are used for characterizing infraspecific taxa have been studied in Scotch pine geographic cultures established in the forest-steppe zone of Siberia. Variation in these characters has been revealed, which reflects the polymorphic structure of the species and the effect of natural selection on the composition of populations in new natural-cimatic conditions. 相似文献
20.
Monitoring environmental pollution in Erzurum by chemical analysis of Scots pine (Pinus sylvestris L.) needles 总被引:3,自引:0,他引:3
Pollution distribution maps of copper (Cu), zinc (Zn) and lead (Pb) for Erzurum province were developed on the basis of chemical analysis of Scots pine (Pinus sylvestris L.) needles collected from randomly selected sampling points during 2 years. The maps show deposition zones for the studied elements and could help in identification of sources and directions of air pollution dispersion. This study indicated that vegetation in Erzurum was greatly endangered by sulphur dioxide (SO(2)), whereas Zn does not pose an immediate threat to vegetation in most of the country's territory. However, in the city center, main and secondary road agglomeration, very high pollution with Pb and Cu could limit growth. Higher levels of SO(2) measured in some areas of Erzurum might be harmful for human and animal health. Results of this study indicated that Scots pine needles were not contaminated by Zn. 相似文献