全文获取类型
收费全文 | 92篇 |
免费 | 1篇 |
国内免费 | 3篇 |
专业分类
安全科学 | 2篇 |
废物处理 | 3篇 |
环保管理 | 4篇 |
综合类 | 26篇 |
基础理论 | 18篇 |
污染及防治 | 32篇 |
评价与监测 | 4篇 |
社会与环境 | 5篇 |
灾害及防治 | 2篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 4篇 |
2012年 | 9篇 |
2011年 | 6篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 3篇 |
2007年 | 1篇 |
2006年 | 6篇 |
2004年 | 5篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 9篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1967年 | 1篇 |
1956年 | 1篇 |
1938年 | 1篇 |
1937年 | 1篇 |
排序方式: 共有96条查询结果,搜索用时 31 毫秒
61.
Mikael Gillner Birgitta Fernstrm Jan-ke Gustafsson Jan Bergman Christian Cambillau 《Chemosphere》1986,15(9-12):1673-1680
We have investigated the capacity of various indoles to inhibit specific binding of [1,6-3H]2,3,7,8-tetrachlorodibenzo-
-dioxin ([3H]TCDD) in rat liver cytosol, as analyzed by electrofocusing in polyacrylamide gels. Of these indoles, indolo[3,2-
]carbazole was the most active. The IC50 value for TCDD receptor binding of indolo[3,2-
]carbazole as well as for 2,3,7,8-tetrachlorodibenzofuran was 3.6 nM. We have also studied the influence on binding exerted by introduction of some substituents on indolo[3,2-
]carbazole. Substitution with methyl groups at the 5 and 11 positions resulted in an increased affinity (IC50 1.2 nM) for the TCDD receptor as compared to the parent compound. Computer-supported molecular structure studies indicated that if the van der Waals radii of atoms are included, a rectangle of 6.8 × 13.7 Å may account for the binding of high-affinity ligands to the TCDD receptor. 相似文献
62.
The processes governing distribution of a xenobiotic compound discharged initially into the environment are discussed, and attention is drawn to (a) binding to organic matter in the sediment phase which affects both persistence and toxicity to biota and (b) the role of atmospheric transport for compounds of low water solubility and high vapour pressure. Important limitations in the use of sum parameters such as EOCI are pointed out. The important distinction between biodegradation and biotransformation is pointed out, and significant experimental determinants noted. Pathways for the aerobic metabolism of chlorophenolic compounds are discussed, and attention is drawn to the role of O‐methylation as an environmentally significant alternative to biodegradation. Evidence for the biodegradation of chlorinated aliphatic acids and hydrocarbons under both aerobic and anaerobic conditions is presented. Anaerobic metabolism of chlorophenolic compounds is discussed with respect to (a) de‐O‐methylation of chloroguaiacols, (b) dechlorination of chlorocatechols and (c) reduction of chlorovanillins. It is emphasized that current evidence provides a complex metabolic picture, and that only partial dechlorination may occur. Brief attention is given to the important issue of the persistence of chlorolignin, and attention drawn to technical issues which render this problem difficult of access by traditional procedures. Biohalogenation—particularly by fungi—is noted, though its quantitative contribution cannot be estimated at the moment. A number of important unresolved issues are underscored: (a) the problem of determining rates of microbial reactions which may be translated to environmental situations, (b) the cardinal role not only of the number of chlorine atoms in an aromatic compound but also the substitution pattern and (c) limitations in current understanding of the role of anaerobic bacteria in bringing about biodegradation and biotransformation. 相似文献
63.
Åke Sjödin David A. Cooper Kenth Andréasson 《Journal of the Air & Waste Management Association (1995)》2013,63(3):186-190
Abstract Ambient air measurements of N2O, NOx, CO, and HC based on grab sampling were conducted in a major traffic tunnel in Sweden, that carries up to 4,000 vehicles per hour, in order to estimate real-world emissions of N2O for road traffic. Two different methods—relative and mass balance—were used to calculate a N2O emission factor for the mixed vehicle fleet, which gave an average emission factor, at average speeds of 30-70 km/h, of approximately 25 mg N2O/ km, with a range of 7-56 mg/km. 相似文献
64.
The dynamics of accumulation and loss of different physico-chemical forms of 106Ru were measured in the euphausiid Meganyctiphanes norvegica. The accumulation of 106Ru was directly related to the concentration of the radioisotope in solution, as evidenced by similar concentration factors for euphausiids in the low and high activity 106Ru chloride solutions. The chemical form of the radioisotope in solution had a pronounced effect on the uptake, with 106Ru chloride fractions being accumulated at a faster rate than 106Ru nitrosyl-nitrato complexes. Euphausiids lost 106Ru, previously accumulated from the 106Ru chloride complexes, at a faster rate than 106Ru which had been accumulated from 106Ru nitrosyl-nitrato forms. Also, in the case of the 106Ru chloride complexes, the loss rate was inversely proportional to the time allowed for isotope accumulation. The process of molting greatly accelerated the loss of 106Ru from euphausiids, with first molts shed during the loss phase accounting for 70 to 80% of the total 106Ru body burden. When euphausiids accumulated 106Ru from the food chain, the initial-loss rate was rapid due to large amounts of the radioisotope associated with fecal pellets; however, no relationship was found between loss rate and the number of food rations received. Molts from these individuals did not contain 106Ru, thus, loss from euphausiids obtaining this radioisotope through the food chain is mainly due to fecal pellet deposition and other excretion or exchange processes. 相似文献
65.
Linderholm L Jakobsson K Lundh T Zamir R Shoeb M Nahar N Bergman Å 《Journal of environmental monitoring : JEM》2011,13(10):2728-2734
Persistent organic pollutants (POPs) and heavy metals are well known environmental pollutants. Even though numerous studies have been carried out to assess human exposures to these compounds, there is still a lack of data on humans from developing countries, especially in underprivileged children. The objective of this study was to assess the exposure to POPs and heavy metals in children from Dhaka, Bangladesh. One specific aim was to investigate whether children working at, or living close to, open waste disposal sites (WDSs) were more heavily exposed than other urban children. In 2008, blood and serum were collected from 73 children aged 7-16 from five neighbourhoods. Some of the children lived and worked at WDSs (N = 31), others lived next to a WDS (N = 17), whereas some children lived far from such sites (N = 25). Blood levels of lead (B-Pb), cadmium (B-Cd), and selenium (B-Se) were determined by ICP-MS for all subjects. The metal levels were high, with B-Pb overall mean 120 μg L(-1) (range 40-220), B-Cd 0.74 μg L(-1) (0.22-4.1), and B-Se 120 μg L(-1) (81-170). There were no marked differences between children from the different neighbourhoods, or between WDS workers and other children. PCB levels were low and with no contrast between neighbourhoods, for CB-153 the overall mean was 7.0 ng g(-1) fat (2.8-51). In contrast, high levels of DDTs were observed in all children, for 4,4'-DDE 1300 ng g(-1) fat (420-4600), and for 4,4'-DDT 326 ng g(-1) fat (44-1400), indicating ongoing exposure. PBDE levels were low, and BDE-209 was quantitated mainly in children working at or living close to WDSs. In conclusion, the high levels of DDTs, lead and cadmium observed in children from Dhaka are of concern. Many children were exposed at levels where health effects have been observed, or at levels without safety margins. 相似文献
66.
The sympatric echinoids Diadema savignyi and D. setosum coexist in shallow reef lagoons throughout East Africa. The reproductive strategies of these echinoids were studied to investigate reproductive isolation as a possible mechanism for maintaining the coexistence of these closely related species. The annual reproductive cycle and lunar periodicity were determined by gonad index measurements, histological examination of gametogenesis, and induction of spawning with injections of KCl. The peak reproductive period of D. savignyi coincided with the north-east monsoon period (when light and temperatures are high) as gonad indices were high (>8%) beginning in February and peaked at 9.7% in May. Gonad indices subsequently rapidly decreased (by 26%) in June at the beginning of the cooler south-east monsoon period. However, the presence of sperm and ova in most months of the year indicates continuous gametogenesis with reduced reproductive effort during the cooler months. The annual cycle for D. setosum showed less of a seasonal trend as gonad indices remained above 7% throughout much of the year but tended to be highest when temperatures were lower. This is the first confirmation of continuous reproduction in these two species at the equator. The reproductive patterns of both species remained consistent over 2 years of sampling. Both species exhibited a synchronized lunar spawning periodicity during the 3 months sampled, with D. setosum spawning on lunar days 8–10 and D. savignyi spawning after the full moon (lunar days 17–18). Whereas spawning in D. savignyi was very tightly synchronized, 20% of D. setosum individuals still spawned after the peak spawning period. The coexistence of these closely related species appears to be maintained by temporal reproductive isolation during the lunar spawning period reinforced by seasonal differences in reproductive effort.Communicated by O. Kinne, Oldendorf/Luhe 相似文献
67.
68.
69.
70.
Many chemicals in use today lack appropriate documentation on their environmental properties, fate, and effects. To counteract this lack of documentation it is vital to thoroughly investigate a compound’s fate in the environment before it comes into use. The present study is describing a novel method for assessing the reduction potential of polybrominated diphenyl ethers (PBDEs), as a part of a project aimed to create an experimental model for determination of chemical persistence. The reductive transformation of 15 PBDE congeners using sodium borohydride was determined. Pseudo-first-order reaction rate constants of the transformations were determined by monitoring the disappearance of the investigated congeners. The reductions lead primarily to formation of lower brominated PBDEs. Each PBDE congener was tested in a total of ten replicates which showed a relative standard deviation of 31% or less. The decaBDE, BDE-209 was approximately 3 times as prone to reductive transformation as BDE-207. The three nonaBDEs, BDE-206, BDE-207, and BDE-208, showed similar reductive potential. The reactivity of the tested octaBDEs was quite variable, from 5% to 24% of the reactivity of BDE-209 for BDE-196 and BDE-198, respectively. The heptaBDEs studied were in the range of the less reactive octaBDEs, except for BDE-181 which was as high as 13% of the reactivity of BDE-209. The results presented give a method for measuring the propensity of PBDEs, and possibly similar compounds, to undergo reductions. They indicate a potential route to a vital piece of information in the assessment of environmental persistence of chemicals. 相似文献