全文获取类型
收费全文 | 547篇 |
免费 | 12篇 |
国内免费 | 10篇 |
专业分类
安全科学 | 23篇 |
废物处理 | 20篇 |
环保管理 | 132篇 |
综合类 | 71篇 |
基础理论 | 90篇 |
污染及防治 | 173篇 |
评价与监测 | 23篇 |
社会与环境 | 32篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 6篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 7篇 |
2019年 | 11篇 |
2018年 | 13篇 |
2017年 | 18篇 |
2016年 | 20篇 |
2015年 | 14篇 |
2014年 | 13篇 |
2013年 | 70篇 |
2012年 | 19篇 |
2011年 | 26篇 |
2010年 | 23篇 |
2009年 | 23篇 |
2008年 | 29篇 |
2007年 | 34篇 |
2006年 | 31篇 |
2005年 | 8篇 |
2004年 | 20篇 |
2003年 | 14篇 |
2002年 | 19篇 |
2001年 | 11篇 |
2000年 | 8篇 |
1999年 | 13篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 10篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 9篇 |
1987年 | 7篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1983年 | 2篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1977年 | 5篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有569条查询结果,搜索用时 15 毫秒
501.
Alteration of DNA methylation is a major epigenetic mechanism associated with the effects of nongenotoxic carcinogens. We evaluated the effects of two environmental pollutants, hexabromocyclododecane (HBCD), 17-beta oestradiol (E(2)) as well as 5-aza 2' deoxycytidine (5AdC) on global DNA methylation levels (5-methyl 2' deoxycytidine) in the liver and gonads of the three-spine stickleback (Gasterosteus aculeatus). HBCD at 30 and 300 ng/L of water did not produce statistically significant differences in global genomic methylation in liver of female stickleback. On the other hand, the methylation inhibitor, 5-aza-2'-deoxycytidine, significantly lowered hepatic global methylation levels in these fish by 14% (P<0.05). The naturally occurring oestrogen, 17-beta oestradiol (E(2)) at 100 ng/L also decreased global DNA methylation levels in female liver but this effect was not statistically significant. In contrast, both E(2) and 5AdC caused statistically significant (P<0.001 and P<0.01 respectively) global genomic hypermethylation in the gonads of male sticklebacks although the increase seen in the female gonads was not statistically significant. The male gonad effect though unexplained may potentially be an indirect response to hypomethylation in other tissues (such as the liver) and may have important implications regarding oestrogenic effects in fish. The contrasting effects of HBCD and E(2) on global DNA methylation in stickleback should contribute to the integrated risk assessment of these environmental chemicals. 相似文献
502.
Assessment of indoor exposure to polybrominated diphenyl ethers (PBDEs) requires a critical examination of methods that may influence exposure estimates and comparisons between studies. We measured PBDEs in residential dust collected from 20 homes in Boston, MA, to examine 5 key questions: 1) Does the choice of dust exposure metric-e.g., concentration (ng/g) or dust loading (ng/m2)-affect analysis and results? 2) To what degree do dust concentrations change over time? 3) Do dust concentrations vary between rooms? 4) Is the home vacuum bag an acceptable surrogate for researcher-collected dust? 5) Are air and dust concentrations correlated for the same room? We used linear mixed-effects models to analyze the data while accounting for within-home and within-room correlations. We found that PBDE dust concentration and surface loading were highly correlated (r=0.86-0.95, p<0.001). Average dust concentrations did not significantly differ over an 8-month period, possibly because home furnishings changed little over this time. We observed significant differences between rooms in the same home: PBDE concentrations in the main living area were 97% higher than the bedroom for decaBDE (p=0.02) and 72% higher for pentaBDE (p=0.05). Home vacuum bag dust concentrations were significantly lower than researcher-collected dust and not strongly correlated. Air (vapor and particulate phase) and dust concentrations were correlated for pentaBDE (p=0.62, p<0.01), but not for decaBDE (p=0.25). In addition, potential markers of BDE 209 debromination (BDE 202 and the BDE197:BDE201 ratio) were also observed in household dust samples. One vacuum bag sample contained the highest concentrations of BDE 209 (527,000 ng/g) and total PBDEs (544,000 ng/g) that have been reported in house dust. 相似文献
503.
Allen S. Heagle John W. Johnston 《Journal of the Air & Waste Management Association (1995)》2013,63(7):729-732
Foliar injury and shoot fresh weight responses of soybeans (Glycine max L.) ‘Lee 68’ and ‘Dare’ exposed to mixtures of ozone (O3) and sulfur dioxide (SO2) were greater than additive (synergistic), less than additive (antagonistic), or additive. The result depended on the concentrations of O3 and SO2, the exposure duration, and the amount of injury caused by each gas singly. Synergism usually occurred when injury from O3 or SO2 singly was slight to moderate. Antagonism usually occurred when injury from either gas singly was severe. In many cases of antagonism, the injury and fresh weight effects of the mixture were less than those from SO2 alone, suggesting that O3 can sometimes protect soybeans from SO2. 相似文献
504.
505.
This paper examines the rate of degradation of food waste in a leach bed reactor (LBR) under four different operating conditions. The effects of leachate recirculation at a low and high flow rate are examined with and without connection to an upflow anaerobic sludge blanket (UASB). Two dilution rates of the effective volume of the leach bed reactors were investigated: 1 and 6 dilutions per LBR per day. The increase in dilution rate from 1 to 6 improved the destruction of volatile solids without connection to the UASB. However connection to the UASB greatly improved the destruction of volatile solids (by almost 60%) at the low recirculation rate of 1 dilution per day. The increase in volatile solids destruction with connection to the UASB was attributed to an increase in leachate pH and buffering capacity provided by recirculated effluent from the UASB to the leach beds. The destruction of volatile solids for both the low and high dilution rates was similar with connection to the UASB, giving 82% and 88% volatile solids destruction respectively. This suggests that the most efficient leaching condition is 1 dilution per day with connection to the UASB. 相似文献
506.
Walter W. Heck Allen S. Heagle 《Journal of the Air & Waste Management Association (1995)》2013,63(2):97-99
With newly developed monitoring techniques, investigators used the sensitive tobacco variety, Bel-W3, as a monitor for photochemical air pollution at different locations within 75 miles of Cincinnati, Ohio. Observations during the summers of 1966 through 1968 revealed almost daily injury to monitoring plants, fairly uniform total seasonal injury at all locations, and a marked variation in both oxidant and injury from one season to another within the city. The relationship between oxidant level and injury was not found to be consistent. 相似文献
507.
In Florida, more than half of the state’s sandy beach coastlines are designated as critical erosion areas by the Florida Department
of Environmental Protection (FDEP 2008). At the same time, the economic contribution of coastal construction is being confounded by the fiscal peril facing Florida
(Bird in Ann Geomorph 57:1–9, 1985, Pew Center on the States 2009, U.S BEA 2009). It is therefore an opportune time for an evaluation of coastal erosion policy response which specifically addresses coastal
construction. Furthermore in Florida, an increasing coastal population requiring the provision of structural development necessitates
an improved understanding of how legislative intent which avoids the cumulative impacts of development is translated through
quantified policy response. This study characterizes how coastal development trends in Florida have responded to critical
erosion designation. Using spatial and temporal analysis of coastal construction permitting data from 1987 to 2007, three
coastal counties in northwest Florida were selected for this study. This selection was based on proximity to the designated
ecologically sensitive Apalachicola National Estuarine Research Reserve (ANERR). This study has indicated that clusters of
development have not been reduced or redirected by critical erosion designation in certain areas of the study counties. Therefore
this study has implications for the regulatory framework governing coastal development permitting in Florida, which is of
timely relevance for sea-level rise adaptation. 相似文献
508.
509.
510.
Xiaobin Liao Joshua M. Allen Caroline O. Granger Susan D. Richardson 《环境科学学报(英文版)》2022,34(7):264-275
Halogenated disinfection byproducts (DBPs) are an unintended consequence of drinking water disinfection, and can have significant toxicity. XAD resins are commonly used to extract and enrich trace levels of DBPs for comprehensive, nontarget identification of DBPs and also for in vitro toxicity studies. However, XAD resin recoveries for complete classes of halogenated DBPs have not been evaluated, particularly for low, environmentally relevant levels (ng/L to low µg/L). Thus, it is not known whether levels of DBPs or the toxicity of drinking water might be underestimated. In this study, DAX-8/XAD-2 layered resins were evaluated, considering both adsorption and elution from the resins, for extracting 66 DBPs from water. Results demonstrate that among the 7 classes of DBPs investigated, trihalomethanes (THMs), including iodo-THMs, were the most efficiently adsorbed, with recovery of most THMs ranging from 50%-96%, followed by halonitromethanes (40%-90%). The adsorption ability of XAD resins for haloacetonitriles, haloacetamides, and haloacetaldehydes was highly dependent on the individual species. The adsorption capacity of XAD resins for haloacetic acids was lower (5%-48%), even after adjusting to pH 1 before extraction. Recovery efficiency for most DBPs was comparable with their adsorption, as most were eluted effectively from XAD resins by ethyl acetate. DBP polarity and molecular weight were the two most important factors that determine their recovery. Recovery of trichloromethane, iodoacetic acid, chloro- and iodo-acetonitrile, and chloroacetamide were among the lowest, which could lead to underestimation of toxicity, particularly for iodoacetic acid and iodo-acetonitrile, which are highly toxic. 相似文献