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41.
Water Resources - Hydrological runoff prediction in a reliable and precise manner contributes significantly to the optimal management of hydropower resources. Considering the importance of runoff... 相似文献
42.
Al Hasa phosphates constitute the second phosphatic deposit exploited by the Jordan phosphate Mines Company. To investigate the radioactivity of these phosphates, 13 samples of poor phosphatic rocks of an area not exploited at the present time were selected to commence with. This is not the place to discuss either the origin of phosphates in a general manner or Al Hasa phosphates in particular. The literature on the first is effectively voluminous. But as regards the latter, there is little written material. Only some short statements not surpassing the generalities are found in (Heimbach, 1962; Kemmer, 1964; Bender, 1968; Youssef et al., 1969; Reeves & Saadi, 1971). It is hoped that radioactivity studies, especially when integrated with other domains of investigation, might afford a good way of clarifying their origin. Moreover, should the occasion arise, they might serve as the beginning to researches concerning uranium recovery from these phosphates. 相似文献
43.
Muhammad Khalifa Nadir Ahmed Elagib Bashir Mohammed Ahmed Lars Ribbe Karl Schneider 《水文科学杂志》2020,65(Z3):153-168
ABSTRACTUnderstanding the human–water–food–climate nexus is central to achieving sustainable intensification (SI) in agriculture. This research uses a socio-hydrological approach to understand the underpinning for implementing SI in the Gezira Irrigation Scheme, Sudan, by integrating vegetation indices derived from remote sensing, ancillary, gridded soil and precipitation data, supplemented by interviews with 393 farmers. The productivity gap was estimated as the difference between the potential and actual productivities. Based upon data on farmers’ socio-economic status and field practices, a regression tree model was built to determine the factors that control the sorghum yield. The model revealed that the financial status of farmers and access to water are the most influential factors on sorghum yield. A conceptual framework that elucidates SI and its bi-directional feedback to the environment, society and the economy is proposed. Implementing SI in the scheme has implications on water and food security in Sudan and beyond its borders. 相似文献
44.
Hydrogeologic assessment—Figeh Spring,Damascus, Syria 总被引:2,自引:0,他引:2
P. E. Lamoreaux Travis H. Hughes Bashir A. Memon Neal Lineback 《Environmental Geology》1989,13(2):73-127
Hydrogeological studies at Figeh Springs were directed to determine groundwater flow paths, research, storage and discharge units, and the maximum reliable yield. The project was designed to provide information upon which to base pumpage to augment low-season flows from the spring which is the major water supply for the city of Damascus, Syria.As a basis for conclusions and recommendations, work included extensive surface geologic mapping, air photographic interpretation, a detailed well and spring inventory, and a quality of water sampling program. Geologic structural work included mapping and jointing, faulting, and folding, and an analysis of their impact on groundwater movement. 相似文献
45.
Application of an Improved Flow-Stress-Damage Model to the Criticality Assessment of Water Inrush in a Mine: a Case Study 总被引:1,自引:0,他引:1
H. Q. Zhang Y. N. He C. A. Tang Bashir Ahmad L. J. Han 《Rock Mechanics and Rock Engineering》2009,42(6):911-930
This paper presents a case study of water inrush on a mine working face from roof strata. The flow-rock failure process analysis
(F-RFPA2D) code with an improved flow-stress-damage (FSD) model was adopted to perform the failure and coupling analysis. The improved
FSD model was used to represent the permeability variation at the four stages (elastic, damaged, cracked, and crack closure)
of the rock failure process. The fracture initiation, propagation, and coalescence in the stressed strata and the seepage
field evolution in the stress field are represented visually during the whole process of water inrush. The failure zone with
high permeability induced by mining disturbance becomes the water-conducting zone after full excavation of the coal seam.
The height of the water-conducting zone obtained in this study is in reasonable accordance with that predicted by an empirical
formula. It is definitely clarified that the water inrush from the roof strata is induced by the failure zone full of vertical
coalesced mine fractures. It is unlikely that roof accidents resulting in water inrush would occur if the water-conducting
zone does not grow upwards into the aquifer. The main task for mine extraction under a confined aquifer is to locate the aquifer
and find the maximum height of the water-conducting zone, which is very important for mine construction and support design. 相似文献
46.
Bashir?A.?MemonEmail author Michael?R.?Burston Gheorghe?M.?Ponta Daniel?J.?Bonanni 《Environmental Geology》2007,51(7):1203-1211
A tanker truck overturned releasing about 11,350 l of aviation fuel. As two municipal supply wells were within about 396 m
of the release, contaminated soil was excavated and an assessment of hydrologic conditions was completed. A recovery well
(RW) and five monitoring wells were installed. Ground-water samples were collected periodically from these wells and the municipal
supply wells for analysis for volatile organic compounds. Pumping tests were completed on the RW and one municipal supply
well. The results of the pumping test on the RWs were used to design a remediation system to remove jet fuel components from
the ground water. The pumping tests also demonstrated that there was a ground-water divide separating the spill site from
the municipal supply wells. After about 7 months of remediation, samples from the RW and municipal supply wells were clean
and the state issued a clean closure. 相似文献