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111.
Apparent Relative Retardation of Tritium and Bromide in Dolomite 总被引:1,自引:0,他引:1
Darrell I. Leap 《Ground water》1992,30(4):549-558
112.
Underlying the site of a proposed development is a chalk aquifer, groundwater levels are close to the surface. The storm water from the development is to be drained into a lake in the center of the development. Because of the high groundwater levels the effect of this lake has been studied by means of a simple localized mathematical model. It is shown that such a model can give results of sufficient accuracy with regard to probable changes in groundwater levels caused by the development. 相似文献
113.
Small island developing states (or SIDS) are exposed to a large number of natural hazards and many characteristics of small
island developing states make them particularly vulnerable to the impacts of natural hazards. In spite of this acknowledged vulnerability, there are relatively few studies which focus
on the impacts of natural hazards in these countries. This paper presents a review of our current state of knowledge of impacts
in small island developing states and highlights a number of research needs. Central to these is the need to integrate natural
hazards research within a sustainable development context and the need to exploit existing procedures such as government coordinated
disaster impact assessments to generate a detailed understanding of natural hazards impacts. 相似文献
114.
We analyse recent claims of an additional risk of diffusive intrusion by marine organic contamination (OC) into coastal aquifers, and discuss the activity-driven “salt-pump mechanism” which is claimed to accelerate this diffusion. The reported accelerations of transport of OC out of saltwater are far too large to be due to activity effects on simple diffusion. There probably is a small acceleration of diffusion out of saltwater, but there is no direct experimental evidence for this. Possible experimental artefacts are suggested. Larger effects on diffusion in the literature are shown to be not relevant to this problem. Diffusion of suspended OC, present in the experiments, is too slow to be significant; however, this suspended material is shown to have serious implications for the proposed interpretation of the results. Until these results are better understood, no conclusions about any possible environmental implications can be drawn from them.
相似文献
D. R. LloydEmail: Phone: +353-1-6081726Fax: +353-1-6712826 |
115.
116.
The motion of vapour clouds released into the upper atmosphere appears, in most cases, to be satisfactorily explained by assuming they take up those of the ambient atmosphere, but down-leg releases occasionally show anomalies which have yet to be explained. 相似文献
117.
D. Rees G. Haerendel D.G. Felgate K.H. Lloyd C.H. Low 《Planetary and Space Science》1973,21(7):1237-1249
Two Skylark sounding rockets carrying chemical seeding payloads were launched from Woomera, South Australia in October 1969. In conjunction with these firings, the F-region drifts were determined with the Buckland Park aerial array and the results compared with the observed motion of the barium ion clouds. The local ionospheric Sq current system was calculated both from the observed ionospheric parameters and from ground-based magnetograms and the differences between the two results are discussed. 相似文献
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120.
T. Lloyd Evans M. E. Hurst P. J. Sarre 《Monthly notices of the Royal Astronomical Society》2000,319(1):111-120
The optical spectrum of the carbon star IRAS 12311−3509 is dominated by the Merrill–Sanford emission bands of SiC2 , by absorption and emission in the Swan system of C2 , and by resonance emission lines of neutral metals. The infrared energy distribution is flat from 1 to 60 μm. These observations are interpreted as arising from a star with a cool dusty disc which is edge-on to the observer and obscures direct starlight. The infrared continuum is caused predominantly by absorption of stellar light by dust in the disc and re-emission at longer wavelengths. The optical stellar spectrum is seen by reflection off dusty material which lies out of the plane of the disc, and the molecular and atomic emission arises in the same geometry through resonance fluorescence. The object has similarities to the J-silicate stars, but may have a carbon-rich rather than oxygen-rich disc. A full spectroscopic assignment and discussion of the SiC2 bands and their intensities are given. Modelling of the rotational contours of the band yields a rotational temperature of 250 K, indicating very cool gas. 相似文献