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41.
Al-Mutairi Abdulaziz N. Galmed Mahmoud A. Aldamegh Khaled S. 《Arabian Journal of Geosciences》2015,8(4):2327-2339
Arabian Journal of Geosciences - The bauxite ore deposits are mainly found around the Az Zabirah area in the central northern part of Saudi Arabia. The age of the Az Zabirah bauxites was suggested... 相似文献
42.
43.
Farouk M. Mahmoud 《Astrophysics and Space Science》1995,234(1):107-123
Temperature variations of the flare star, EV Lac, at its quiet-state luminosity were computed from its colour indices,B - V, which were measured in Johnson's system, these daily temperature changes are the essential reason of the short-term behaviour appearance in the flare star which is due to the presence of active region(s) causing a temperature difference of a few hundred degrees from the photosphere. A correlation between the annual mean of temperature variations of the flare star at its quiet-state and the annual rate of some physical parameters of the flare star at its active-state was detected. This correlation can interpret the occurrence of the long-term behaviour of the flare star at its quiescent-state as found by Mavridiset al. (1982). 相似文献
44.
The problem of the detailed structure of magnetogasdynamic shock waves is investigated. It is assumed that the flow takes place under normal magnetic fieldH
0 and the conductivity of the medium is considered infinite. An approximate analytical solution of the nonlinear differential equations describing the phenomena is obtained. The suggested analytical results in this paper are in good agreement with the previous numerical computations for the thickness and the velocity distribution inside the transition region. In addition, the enthalpy distribution inside the shock front is predicted. 相似文献
45.
46.
Properties of dust-acoustic solitary waves in a warm dusty plasma are analyzed by using the hydrodynamic model for massive dust grains, electrons, ions, and streaming ion beam. For this purpose, Korteweg-de Vries (KdV) equation for the first-order perturbed potential and linear inhomogeneous KdV-type equation for the second-order perturbed potential have been derived and their analytical solutions are presented. In order to show the characteristics of the dust-acoustic solitary waves are influenced by the plasma parameters, the relevant numerical analysis of the KdV and linear inhomogeneous KdV-type equations are obtained. The dust-acoustic solitary waves, as predicted here, may be associated with the nonlinear structures caused by the interaction of polar jets with the interstellar medium, which is known as Herbig-Haro objects. 相似文献
47.
Water Resources - The scour and flow field patterns with accumulation of debris around bridge piers are completely different due to the reduction of flow area and the increase in depth average... 相似文献
48.
Vizvári Béla Golabi Mahmoud Nedjati Arman Gümüşbuğa Ferhat Izbirak Gokhan 《Natural Hazards》2019,99(1):571-597
Natural Hazards - In this study, a relief system for a large metropolitan city exposed to serious earthquakes is designed and a top-down approach is applied. Afflicted people’s states and... 相似文献
49.
50.
Mahmoud S. Alyamani 《GeoJournal》1999,48(4):291-297
In Wadi Tharad the groundwater has been subjected to hydrochemical study to identify the process (s) that led to the formation
of relatively highly saline water in shallow alluvial aquifer. The chemical analyses results show that the groundwater salinity
was highly variable and randomly distributed along the wadi course. This variation could be attributed to intensive evaporation
on effluent prone surface irrigation water that led to precipitation of evaporates (e.g., calcite, dolomite, gypsum and probably
halite). The intensive irrigation practice through mineral dissolution recharged the groundwater with a marked increase in
the salinity. The local hydrogeological condition is also involved in determining the risk of the groundwater salinity as
a consequence of irrigation practice.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献