全文获取类型
收费全文 | 157篇 |
免费 | 2篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 5篇 |
废物处理 | 1篇 |
环保管理 | 18篇 |
综合类 | 23篇 |
基础理论 | 55篇 |
污染及防治 | 36篇 |
评价与监测 | 20篇 |
社会与环境 | 6篇 |
灾害及防治 | 4篇 |
出版年
2024年 | 1篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 2篇 |
2018年 | 6篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 8篇 |
2014年 | 3篇 |
2013年 | 22篇 |
2012年 | 6篇 |
2011年 | 4篇 |
2010年 | 8篇 |
2009年 | 14篇 |
2008年 | 7篇 |
2007年 | 12篇 |
2006年 | 7篇 |
2005年 | 7篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1978年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有168条查询结果,搜索用时 750 毫秒
111.
Mean concentration fields of strongly advected non-buoyant discharges are characterised with a double-Gaussian assumption.
Comparisons with experimental data show that the approximation provides a reasonable representation of the cross-sectional
profiles. The self-similarity of these profiles enables their form to be represented by two additional parameters, one describing
the relative separation of the peaks and the other the ratio of the cross-sectional spreads. Values for these additional parameters
are determined from experimental data. This systematic approach to characterising the strongly advected flows provides a consistent
framework for determining spreading rates and concentration ratios, such as the peak to centreline maximum and the peak to
top hat. The double-Gaussian framework also provides a basis for comparisons with the CorJet and VisJet numerical models.
In addition the double-Gaussian assumption is employed to interpret data obtained using the Light Attenuation technique. This
is a relatively simple measuring system, which provides depth integrated concentration information. The data obtained using
this technique is shown to be generally consistent with that from previous studies. 相似文献
112.
C. F. Robson N. C. Davidson J. H. Barne J. P. Doody 《Journal of Coastal Conservation》1996,2(2):179-182
Baseline resource information in an easily accessible form is a vital starting point for developing coastal zone management.
On behalf of a wide-ranging group of organizations involved in the management of the U.K. maritime zone, the Joint Nature
Conservation Committee (JNCC) is compiling a series of 16 regional volumes. The volumes contain multi-disciplinary coastal
zone resource information arranged in ten chapters under the general title ‘Coasts and Seas of the UK’. These volumes form
part of a series of paper and electronic publications of coastal information being produced by JNCC’s Coastal Directories
Project and are designed to meet the needs of planners and all others involved in decision-making and management of the coast. 相似文献
113.
Antonio G. Goulart Davidson M. Moreira Marco T. Vilhena Gervásio A. Degrazia Sergej S. Zilitinkevich 《Environmental Fluid Mechanics》2007,7(5):409-419
Starting from the evolution equation for the turbulent energy density spectrum (EDS), we develop a new model for the growth
of the Convective boundary layer (CBL). We apply dimensional analysis to parameterize the unknown inertial transport and convective
source term in the dynamic equation for the three-dimensional (3-D) spectrum and solve the 3-D EDS equation. The one-dimensional
vertical spectrum is derived from the 3-D spectrum, employing a weight function. This allows us to select the magnitude of
the vertical spectral component for the construction of the growing 3-D EDS. Furthermore, we employ the vertical component
of the energy spectrum to calculate the eddy diffusivity (required in dispersion models). Currently there are no available
experimental data to directly verify our EDS model. 相似文献
114.
An ultrasonic bath and an ultrasonic probe have been used to develop rapid versions of the three-stage Community Bureau of Reference (BCR, now the Standards, Measurement and Testing Programme) sequential extraction procedure. The effect of the ultrasonic treatments on the extraction of copper, iron, manganese and zinc from a sewage sludge-amended soil has been assessed. Recoveries similar to those of conventional shaking (i.e., conventional value, +/- 30%) could generally be obtained for copper, manganese and zinc, but not for the important matrix element iron. With the use of compromise sonication conditions, steps 1, 2 and 3 of the sequential extraction (excluding the hydrogen peroxide digestion in step 3, which was not performed with sonication) could be completed in 3, 5 and 1 min, respectively, using the ultrasonic probe, and in 3, 1 and 1 h, respectively, using the bath. The extraction procedures developed using the soil performed well when applied to lake sediment BCR CRM 601. Analyte partitioning was generally similar to that obtained with mechanical shaking, and overall metal recoveries were 84-98% of those obtained with the conventional BCR protocol, except for copper extracted with the probe (74%). Poorer performance (analyte recoveries, 58-104%) was obtained when the methods were applied to an intertidal sediment. This highlights the difficulty of developing a version of the BCR extraction, with ultrasonic assistance, which gives a performance equivalent to conventional shaking when applied to different substrates. 相似文献
115.
C.?N.?WhittakerEmail authorView authors OrcID profile R.?I.?Nokes H.-Y.?Lo P.?L.-F.?Liu M.?J.?Davidson 《Environmental Fluid Mechanics》2017,17(5):929-958
This paper presents a study of the waves generated by a solid block landslide moving along a horizontal boundary. The landslide was controlled using a mechanical system in a series of physical experiments, and laser-induced fluorescence measurements resolved both spatial and temporal variations in the free surface elevation. During its constant-velocity motion, the landslide transferred energy into ‘trapped’ offshore-propagating waves within a narrow frequency band. The wave trapping is demonstrated by investigating the wave dispersion characteristics using a two-dimensional Fourier Transform. The first of the trailing waves broke at Froude numbers greater than or equal to 0.625. The parametric dependence of the largest-amplitude waves and the potential energy within the wave field are discussed. The experimental results were compared to the predictions of an incompressible Navier–Stokes solver with and without turbulence models. The numerical model under-predicted the measured wave amplitudes, although it accurately predicted the measured wave phasing. The turbulent model more accurately predicted the shapes of the trailing waves. Both experimental and numerical results confirmed that investigations into wave generation by submerged objects moving at constant velocity should also consider the initial acceleration of the object, as this affects the overall evolution of the wave field. The applicability of the horizontal-boundary results to more realistic field scenarios is discussed. 相似文献
116.
117.
Extractability and mobility of mercury from agricultural soils surrounding industrial and mining contaminated areas 总被引:1,自引:0,他引:1
This study focussed on a comparison of the extractability of mercury in soils with two different contamination sources (a chlor-alkali plant and mining activities) and on the evaluation of the influence of specific soil properties on the behaviour of the contaminant. The method applied here did not target the identification of individual species, but instead provided information concerning the mobility of mercury species in soil. Mercury fractions were classified as mobile, semi-mobile and non-mobile. The fractionation study revealed that in all samples mercury was mainly present in the semi-mobile phase (between 63% and 97%). The highest mercury mobility (2.7 mg kg(-1)) was found in soils from the industrial area. Mining soils exhibited higher percentage of non-mobile mercury, up to 35%, due to their elevated sulfur content. Results of factor analysis indicate that the presence of mercury in the mobile phase could be related to manganese and aluminium soil contents. A positive relation between mercury in the semi-mobile fraction and the aluminium content was also observed. By contrary, organic matter and sulfur contents contributed to mercury retention in the soil matrix reducing the mobility of the metal. Despite known limitations of sequential extraction procedures, the methodology applied in this study for the fractionation of mercury in contaminated soil samples provided relevant information on mercury's relative mobility. 相似文献
118.
Madrid F Reinoso R Florido MC Díaz Barrientos E Ajmone-Marsan F Davidson CM Madrid L 《Environmental pollution (Barking, Essex : 1987)》2007,147(3):713-722
Metals released by the extraction with aqua regia, EDTA, dilute HCl and sequential extraction (SE) by the BCR protocol were studied in urban soils of Sevilla, Torino, and Glasgow. By multivariate analysis, the amounts of Cu, Pb and Zn liberated by any method were statistically associated with one another, whereas other metals were not. The mean amounts of all metals extracted by HCl and by SE were well correlated, but SE was clearly underestimated by HCl. Individual data for Cu, Pb and Zn by both methods were correlated only if each city was considered separately. Other metals gave poorer relationships. Similar conclusions were reached comparing EDTA and HCl, with much lower values for EDTA. Dilute HCl extraction cannot thus be recommended for general use as alternative to BCR SE in urban soils. 相似文献
119.
120.
Enhanced soil element concentrations may serve as indicators not only of modern pollution, but also of former historic and/or pre-historic human activity. However, there is little consensus over the most appropriate means of extraction for identifying chemical signatures of modern and archaeological pollution. This study addressed this question by using a 5-step sequential extraction to examine the partitioning of elements within the soil. Samples were taken from known functional areas (hearth, house, byre, arable, and grazing areas) on a 19th century abandoned croft (small farm). A hot nitric acid digest and five-stage sequential extraction method were used to examine the partitioning of elements in soil and identify the current elemental distribution of anthropogenic contamination. The results indicate that although a significant proportion of Ca tends to be bound with exchangeable and weak acid soluble fractions, in the hearth and house areas there is also a significant proportion held within the recalcitrant residue. Pb concentrations tend to be associated with organic matter, ammonium oxalate extractable fractions and the residue, whilst Zn generally has a more even partitioning between the six soil fractions. The implications of this for extraction methodology are element and soil specific. However, the presence of a significant proportion of anthropogenically significant elements (including Ca, Pb, Zn, Sr, and Ba) within the resistant residue suggests the use of only a weak acid or an exchangeable fraction extraction would result in the loss of information from contamination resulting from former human activity. Hence, a total or pseudo-total extraction method is recommended for this type of study. 相似文献