全文获取类型
收费全文 | 401篇 |
免费 | 4篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 5篇 |
环保管理 | 67篇 |
综合类 | 32篇 |
基础理论 | 155篇 |
污染及防治 | 94篇 |
评价与监测 | 28篇 |
社会与环境 | 9篇 |
灾害及防治 | 1篇 |
出版年
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2017年 | 9篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 12篇 |
2013年 | 18篇 |
2012年 | 15篇 |
2011年 | 19篇 |
2010年 | 10篇 |
2009年 | 8篇 |
2008年 | 22篇 |
2007年 | 25篇 |
2006年 | 17篇 |
2005年 | 12篇 |
2004年 | 11篇 |
2003年 | 8篇 |
2002年 | 18篇 |
2001年 | 10篇 |
2000年 | 17篇 |
1999年 | 16篇 |
1998年 | 6篇 |
1997年 | 9篇 |
1996年 | 4篇 |
1995年 | 9篇 |
1994年 | 5篇 |
1993年 | 8篇 |
1992年 | 11篇 |
1991年 | 8篇 |
1990年 | 9篇 |
1989年 | 5篇 |
1988年 | 8篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 1篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1969年 | 1篇 |
1959年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有405条查询结果,搜索用时 15 毫秒
191.
Ffion C. W. Davies 《Environmental geochemistry and health》1991,13(1):35-38
Minamata disease first became evident in Japan in 1956 and was caused by methyl mercury exposure. Over 20,000 people are now thought to have been affected. This article compares the situation immediately following the initial discovery with that now prevalent.The author, then a final year medical student, spent her elective period (a nine week study period) in the area in the summer of 1989. This paper is based on that experience and is published in order to provide an update on a classic pollution episode which was widely publicised in the years immediately after its discovery but about which less has been heard in recent years. 相似文献
192.
Improvement in collective performance with experience in ants 总被引:3,自引:4,他引:3
Elizabeth?A.?Langridge Nigel?R.?FranksEmail author Ana?B.?Sendova-Franks 《Behavioral ecology and sociobiology》2004,56(6):523-529
We show that entire ant colonies can improve their collective performance progressively when they repeat the same process. Colonies of Leptothorax albipennis can reduce their total emigration times over successive emigrations. We show that this improvement is based on experience and some memory-like process, rather than a coincidental developmental change or an increased general level of arousal. We demonstrate that the benefits of experience can be lost (i.e. forgotten) if the interval between successive emigrations is too long. We also show that the benefits of experience are more likely to be retained over a longer period if the collective performance has been repeated several times. This is a new demonstration of a process akin to learning in ants and we briefly discuss how it may involve not only improvements in individual performance but also improvements in the ways in which the ants interact with one another.Communicated by L. Sundström 相似文献
193.
Weatherley NS Davies GL Ellery S 《Environmental pollution (Barking, Essex : 1987)》1997,95(1):127-134
Organochlorine concentrations in the muscle tissues of eels at 41 freshwater sites across Wales were surveyed in 1993. Positive but weak relationships were detected between eel age or length and the concentration of some organochlorines. Isomers of HCH were below detection at most sites. Dieldrin was widespread at 10-100 microg kt(-1) wet weight, despite its ban in sheep dip in 1989. Total DDT residue concentrations averaged 73 microg kg(-1). Total PCB burdens expressed as Arochlor 1260, were > 50 microg kg(-1) at 76% of sites and > 100 microg kg(-1) at 46% of sites. The range of concentrations was comparable with other UK data. Rural sites had relatively low levels of PCBs, highest contamination occurring in the lower reaches of industrialised catchments. The inferences for environmental effects are discussed. 相似文献
194.
Davies JJ Jenkins A Monteith DT Evans CD Cooper DM 《Environmental pollution (Barking, Essex : 1987)》2005,137(1):27-39
Analysis of water chemistry data from 15 years of monitoring at 22 acid-sensitive lakes and streams in the UK reveals coherent national chemical trends indicative of recovery from acidification. Excess sulphate and base cations exhibit significant decline, often accompanied by an increase in an alkalinity-based determination of acid neutralising capacity (AB-ANC) and, at fewer sites, a decline in hydrogen and labile aluminium. Acid neutralising capacity determined by "charge-balance" (CB-ANC) exhibits few trends, possibly due to compound errors associated with its determination. Trend slopes in excess sulphate correlate with those for base cations, hydrogen ion and AB-ANC, with between-site variability linked to catchment hydrology, sea-salt inputs and forestry. Nitrate concentrations have not changed significantly but show high sensitivity to varying climate. Trends in AB-ANC are influenced by significant increases in dissolved organic carbon, the cause of which it is vital to establish before trends in the former can definitively be attributed to decreasing acidic deposition. 相似文献
195.
Alan J. S. Cuthbertson Janek Laanearu Peter A. Davies 《Environmental Fluid Mechanics》2006,6(2):133-151
Results are presented from a combined analytical and laboratory study of unsteady, two-layer, density-driven, sub-maximal
exchange over a slowly-descending estuarine barrier located very close to the junction of the river mouth and the near-shore
coastal zone. As in the precursor study (Cuthbertson et al. 2004, Environ. Fluid Mech. 4, 127–155) that the present investigation extends, the rate of descent of the barrier is assumed to be sufficiently slow for
the unsteady exchange flow to adjust continuously to the appropriate quasi-steady conditions at every stage of the descent.
The results demonstrate that the thickness of each layer at the barrier crest can be predicted satisfactorily by a hydraulic
analysis that (i) assumes the existence of a single control point at the barrier crest and (ii) incorporates the hydraulic
losses arising from the sudden expansion and contraction of the upper and lower layers, respectively, at the channel exit.
Predictions of the normalised elevations of the interface at the barrier and exit for the “inviscid” maximal exchange case
are shown to coincide with the maximal exchange predictions of Zhu and Lawrence (2000, J. Hydraul. Eng. ASCE 126(12), 921–928). 相似文献
196.
Cuthbertson Alan J.S. Davies Peter A. Coates Michael J. Guo Yakun 《Environmental Fluid Mechanics》2004,4(2):127-155
Results are presented from a series of model studies of the transient exchange flow resulting from the steady descent of an impermeable barrier separating initially-quiescent fresh and saline water bodies having density 0 and 0+()0, respectively. A set of parametric laboratory experiments has been carried out (i) to determine the characteristic features of the time-dependent exchange flow over the barrier crest and (ii) to quantify the temporal increase in the thickness and spatial extent of the brackish water reservoir formed behind the barrier by the outflowing, partly-mixed saline water. The results of the laboratory experiments have been compared with the predictions of a theoretical model adapted from the steady, so-called maximal exchange flow case and good qualitative agreement between theory and experiment has been demonstrated. The comparisons indicate that head losses of between 7% and 3% are applicable to the flow over the ridge crest in the early and late stages, respectively, of the barrier descent phase, with these losses being attributed to mixing processes associated with the counterflowing layers of fresh and saline water in the vicinity of the ridge crest. The experimental data show (and the theoretical model predictions confirm) that (i) the dimensionless time of detection t
det(g/H
b)1/2 of the brackish water pool fed by the dense outflow increases (at a given distance from the barrier) with increasing values of the descent rate parameter g'H
b/(dh
b/dt)2 and (ii) the normalised thickness (x,t)/H
b of the pool at a given reference station increases monotonically with increasing values of the modified time (t–t
det)/(H
b/g)1/2, with the rate of thickening decreasing with increasing values of the descent rate parameter g'H
b(dh
b/dt)2. Here, g=(g/0)()0 is the modified gravitational acceleration, H
b is the mean depth of the water and dh
b/dt denotes the rate of descent of the barrier height h
b with elapsed time t after the two water bodies are first brought into contact. 相似文献
197.
Collaboration between the QUASIMEME and BEQUALM projects has proved to be an effective mechanism to further the development of quality assurance procedures for the measurement of the biological effects of tributyltin (imposex and intersex) to meet the requirements of international and national marine monitoring programmes. The data arising from the Laboratory Performance Studies are demonstrating the level of agreement between laboratories, suggesting factors leading to differences between laboratories, and guiding the development of QA procedures. 相似文献
198.
In a field trial, oiled beach sand was buried in a coastal dune system in south Wales. A monitoring programme was designed to assess the rate of leaching of inorganic ions and hydrocarbons from the deposit. Active breakdown of the weathered oil occurred within the oiled beach sand, but hydrocarbons from the original material, or arising as a result of degradation, did not follow the same leaching pattern as inorganic ions; they remained within the original deposit. The results suggest that weathered oil coming ashore from spills at sea can be mixed with sand and buried to degrade in coastal soils, without risk of groundwater contamination by hydrocarbons. 相似文献
199.
200.
A. J. S. Cuthbertson P. Lundberg P. A. Davies J. Laanearu 《Environmental Fluid Mechanics》2014,14(5):1251-1273
Results are presented from a series of parametric experimental and analytical studies of the behaviour of dense gravity currents along rotating, up-sloping, wedge-shaped channels. High resolution density profile measurements at fixed cross- and along-channel locations reveal the outflowing bottom gravity currents to adjust to quasi-steady, geostrophically-balanced conditions along the channels, with the outflow layer thickness and cross-channel interface slope shown to scale with the inlet Burger number for all experimental conditions tested. A general analytical solution to the classic rotating hydraulics problem has been developed under the assumption of inviscid, zero-potential-vorticity conditions to model dense water flow through a triangular constriction and thus simulate the vee-channel configurations under consideration. Predictions from this zero-PV model are shown to provide good overall quantitative agreement with experimental measurements obtained both under hydraulically-controlled conditions at the channel exit and for subcritical conditions generated along the channel length. Quantitative discrepancies between measurements and analytical predictions are attributed primarily to assumptions and limitations associated with the zero-PV modelling approach adopted, as well as the to the rapid adjustment in outflow characteristics as the channel exit is approached, as characterised by the along-channel variation in densimetric Froude number for the outflows. 相似文献