全文获取类型
收费全文 | 1157篇 |
免费 | 14篇 |
国内免费 | 16篇 |
专业分类
安全科学 | 47篇 |
废物处理 | 41篇 |
环保管理 | 143篇 |
综合类 | 202篇 |
基础理论 | 214篇 |
环境理论 | 1篇 |
污染及防治 | 389篇 |
评价与监测 | 77篇 |
社会与环境 | 55篇 |
灾害及防治 | 18篇 |
出版年
2023年 | 19篇 |
2022年 | 25篇 |
2021年 | 36篇 |
2020年 | 28篇 |
2019年 | 25篇 |
2018年 | 50篇 |
2017年 | 51篇 |
2016年 | 65篇 |
2015年 | 40篇 |
2014年 | 60篇 |
2013年 | 80篇 |
2012年 | 63篇 |
2011年 | 87篇 |
2010年 | 55篇 |
2009年 | 46篇 |
2008年 | 75篇 |
2007年 | 64篇 |
2006年 | 67篇 |
2005年 | 48篇 |
2004年 | 36篇 |
2003年 | 23篇 |
2002年 | 24篇 |
2001年 | 16篇 |
2000年 | 16篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 11篇 |
1996年 | 6篇 |
1995年 | 9篇 |
1994年 | 4篇 |
1993年 | 8篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1966年 | 1篇 |
1961年 | 1篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1958年 | 1篇 |
1957年 | 1篇 |
1954年 | 3篇 |
1951年 | 1篇 |
1936年 | 1篇 |
排序方式: 共有1187条查询结果,搜索用时 15 毫秒
81.
Armenuhi Heqimyan Lilia Narinyan Anna Nikoghosyan Anush Deghoyan Lianna Yeganyan Sinerik Ayrapetyan 《The Environmentalist》2012,32(2):228-235
Age dependency of [3H]-ouabain binding, 45Ca2+ eflux and its magnetosensitivity in rats’ brain cortex and heart muscle tissues were studied. Curves of dose-dependent [3H]-ouabain binding consisted of three components with different affinities (10−7–10−4 M (α1); 10−9–10−7 M (α2); and 10−11–10−9 M (α3)). These curves were also characterized by different dose-dependent kinetics. [3H]-ouabain binding with α3 receptors in brain cortex and heart muscle tissues of young and adult animals had a dose-dependent character, while that
in old ones had a dose-independent character. A 0.2 T static magnetic field (SMF) exposure had modulation effect on ouabain
binding with α1, α2 and α3 receptors in young rats, while in adult ones, only α3 receptors were magnetosensitive. In old animals, SMF exposure had no significant effect on ouabain binding with α3 receptors in brain cortex, while in heart muscle, it had inhibitory effect on it. Age-dependent effect of ouabain impact
on 45Ca2+ efflux showed that all concentrations of ouabain lead to inhibitory effect in young animals’ brain cortex and heart muscle
(with the exception of 10−10 and 10−6 M), while in old ones, it had activation effect as compared with data received without ouabain. SMF exposure in young animals
had activation effect on 45Ca2+ efflux from brain cortex and heart muscle in data without ouabain, and in old rats, 45Ca2+ efflux from brain cortex was magnetic insensitive. In old animals, SMF increased 45Ca2+ efflux even after extra low concentration of ouabain. It is suggested that α3 receptors having a crucial role in the regulation of Na+/Ca2+ exchange serve as age-dependent magnetosensors of excitable cells. 相似文献
82.
Anna Peterson 《Journal of Agricultural and Environmental Ethics》2008,21(6):607-608
83.
84.
Development of a black carbon-inclusive multi-media model: application for PAHs in Stockholm 总被引:1,自引:0,他引:1
A multi-media model was developed for predicting the fate of organic chemicals in the Greater Stockholm Area, Sweden, and applied to selected polycyclic aromatic hydrocarbons (PAHs). Although urban models have been previously developed, this model is novel in that it includes sorption to pyrogenically-derived particles, commonly termed "black carbon" (BC), within the model structure. To examine the influence of BC sorption on environmental fate of PAHs, two versions of the model were generated and run: one in which sorption to BC was included and one in which BC sorption was excluded. The inclusion of BC sorption did not cause any significant variations to air levels, but it did cause an average 20-30% increase in sediment concentrations related to increased sediment solids partitioning. The model also predicted reduced advective losses out of the model domain, as well as chemical potential to diffuse from sediments, whilst total chemical inventory increased. In all cases, the lighter PAHs were more affected by BC inclusion than their heavier counterparts. We advocate the addition of sorption to BC in future multi-media fate and exposure models, which as well as influencing fate will also alter (lower) chemical availability and, thus, wildlife exposure to hydrophobic chemicals. A quantification of the latter was derived with the help of the soot-inclusive model version, which estimated a lowering of dissolved water concentrations between five and >200 times for the different PAHs of this study. 相似文献
85.
Assessment of the effects of soil PAH accumulation by a battery of ecotoxicological tests 总被引:2,自引:0,他引:2
Surface soils were collected at remote, urban and industrial sites in the Southern of Italy in order to evaluate PAH concentrations and assess the toxic effects by a battery of ecotoxicological tests. The tests were performed on whole soils and on both organic and aqueous extracts. Further goal of this study was to integrate the results coming from each test and matrix in a synthetic toxicity index. The highest summation sigmaPAH concentrations were measured at the industrial soil, although this one did not show an high ecotoxicological risk. Among the performed tests, the phytotoxicity tests showed the highest sensitivity. For whole soil, the worst case always has been represented by test through bacteria. Our results could represent the first step toward the selection of a proper battery to characterize the soil ecotoxicological risk. 相似文献
86.
In many species reproduction and embryonic development have been shown to be sensitive to environmental contaminants. Understanding embryonic exposure to environmental contaminants is thus highly important. In this study concentrations of brominated flame retardants (BFRs) were measured in zebrafish eggs after parental exposure for 42 days via the diet. Zebrafish were exposed to two doses of eleven structurally-diverse BFRs. Eight BFRs were detected in the female zebrafish and maternal transfer to eggs was evident for all eight compounds. The highest concentrations in eggs were observed for hexabromocyclododecane (HBCD) and 2,4,4'-tribromodiphenyl ether (BDE 28), followed by 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE 183) and tetrabromobisphenol A 2,3-dibromopropyl ether (TBBPA DBPE). Five potential BFR metabolites were tentatively identified in female fish and maternal transfer was observed also for these compounds. The lipid adjusted concentrations in eggs were significantly higher than the concentrations in female fish for several of the BFRs. Further, the results showed a generally higher transfer in the lower exposure level and also indicated a dependency on the physico-chemical properties of the compounds. 相似文献
87.
Tanning processes performed in drums consume large amounts of water and chemicals, most of which end up in the wastewater. This study explores an alternative approach at an industrial scale to the traditional pickle-chrome tanning method. The new method replaces formic and sulphuric acids with sulphonic aromatic acid. Because it is done without float, there is a sizeable reduction in the amount of added salt and chrome salt as well as an increase in temperatures at the end of the tanning process. From an environmental perspective, the new method offers important advantages. For instance, there is no float addition in the tannage. Also, there are reductions of 94% and 99%, respectively, in the discharge of chlorides and chrome, as well as a 75% reduction in the residual float. Our financial assessment demonstrated that the new method is 42% cheaper than a traditional approach. 相似文献
88.
This study tests an alternative method to the traditional unhairing method used during the process of tanning the hides. The new method is based on the substitution of sodium sulfide by hydrogen peroxide as an unhairing agent in both hair recovery and recirculation of the floats employed in the process. The properties of the hides obtained using the two methods have been compared and the results indicate that those hides have similar physical, chemical, and organoleptic properties. However, the differences existing from an environmental point of view are significant. These include reductions of water consumption (approx 70%), chemical oxygen demand (approx 35%), toxicity (98%) and total kjendhal nitrogen (50%). Also, the risk associated with the production of hydrogen sulfide is eliminated, which implies a great improvement in terms of safety for the workers. Given the large amounts of water and chemical pollution discharged in the process, the reductions in absolute values represent a significant improvement. A financial assessment was carried out to demonstrate that the proposed new system is 16% more economic than the traditional one. 相似文献
89.
Markéta Julinová Marie Dvořáčková Jan Kupec Jitka Hubáčková Martina Kopčilová Jaromír Hoffmann Pavol Alexy Anna Nahálková Ida Vašková 《Journal of Polymers and the Environment》2008,16(4):241-249
Improving biodegradability of PVA/starch blends is a reality already documented by a number of works. Admittedly, mechanical
properties of products (for example, tensile strength) are somewhat worse, but suitable composition optimizing or chemical
modifying of starch may eliminate the problem to a large degree. This work is an attempt to find another potential effect
influencing biodegradability, that of technological procedure for producing films from these blends on an extruder. The procedure
with a so-called pre-extrusion step (two-stage) and dry-blend (single-stage) produced blends of slightest differences in achieved
biodegradability (virtually within limits of experimental error) in aerobic (76 vs. 79%) as well as anaerobic breakdown (48
vs. 52%). Conversely, morphological analysis exhibited superior homogeneity of films prepared by the two-stage process; their
tensile strength was also higher. 相似文献