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961.
Flow records, rising‐stage sediment samplers, and a sand suspension model are used to examine suspended sediment concentrations during major floods caused by tropical cyclones TC Joni and TC Kina in the Rewa River, Fiji. The highest concentrations of total suspended solids were measured during the early stages of TC Kina. The suspension model predicts higher sand concentrations for TC Kina compared with TC Joni because of the larger slope and higher shear stresses during Kina. Extremely high wash load concentrations early in TC Kina are at least partly due to remobilization of fine sediment deposited during the earlier TC Joni flood. Samples from the TC Kina had volumetric concentrations larger than 5%, indicating hyperconcentrated streamflows. Mass‐density shear stresses in the hyperconcentrated flows are up 1·6 times larger than clear‐water shear stresses, but they occur early during low stages of the flood and probably do not result in severe bed erosion. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
962.
We study the static stiff-fluid model for perfect fluid distributions in the presence of incident magnetic field. The magnetic field is surrounded by static stiff fluid of infinite electric conductivity and it is due to the electric current flowing along theZ-axis. The various physical and geometrical properties together with the state of model in absence of magnetic field are also discussed. 相似文献
963.
In the present paper we have studied the stability of the triangular libration points for the doubly photogravitational elliptic restricted problem of three bodies under the presence of resonances as well as under their absence. Here we have found the conditions for stability. 相似文献
964.
This is the second paper of the series where we have considered Brans-Dicke (B-D) theory as well as general scalar tensor
theory of gravitation in higher dimensional space-time model in the false vacuum state. We have examined whether inflationary
solutions are possible both for constant or variable coupling parameter ω. Also the nature of the scalar field and the coupling
parameter are discussed in the asymptotic limit.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
965.
An LRS Bianchi type I string dust cosmological model with and without bulk viscosity following a method used by Letelier and
Stachel, is investigated. To get a determine solution, it is assumed that σ∝θ whereσ is shear and θ is scalar of expansion
and which leads to A =αBn were n is a constant. The physical and geometrical aspects of the model are also discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
966.
A field study was conducted to assess variations in physico-chemical characteristics of water of the springs located within
the boundary of a Central Himalayan town where the springwater is used for drinking purposes. Monitoring of 12 springs was
carried out for three seasons (winter, summer and monsoon). The results indicate direct influence of unplanned sewage disposal
on the springwater quality as reflected by significant regional variations in the concentration of nitrates, chlorides, sulfates,
sulfides and electrical conductivity. Population density varies within the town from 3110 to 14 137 persons/km–2 and has direct relationship with water quality. Springs located in the densely populated area had higher concentrations of
all these compounds. Concentrations of nitrates up to 60 ppm were observed in some springs, making water unsuitable for human
consumption. No significant changes were observed in springwater quality during different seasons.
Received: 3 February 1995 · Accepted: 27 February 1996 相似文献
967.
Some inhomogeneous cosmological models of plane symmetry in presence of electromagnetic field have been obtained. Various physical and geometrical properties of the models with some special cases are also discussed. 相似文献
968.
High resolution FTS sunspot umbral spectra from NSO/Kitt Peak were used to detect rotational lines due to 11 electronic transitions of the molecule AlF, in the wavelength region 4400 – 9000 Å. The presence of lines due to bands C – A (0,0), (0,1), (0,2) and (1,2), D – A (0,0) and (0,1), F – A (0,0), G – A (0,0), and F – B (0,0) is confirmed. Further, the presence of lines due to C – A (1,0) and (1,1) transitions is treated as doubtful because of heavy blending in the region, by rotational lines of TiO. Among the identified lines, those which are well resolved were selected for measurement of equivalent widths. The measured values for the bands D – A (0,0) and F – A (0,0) were used to estimate the respective effective rotational temperatures to be 1240 ± 120 K and 2390 ± 400 K. 相似文献
969.
Shiv S. Kumar 《Astrophysics and Space Science》1972,16(1):52-54
Arguments are presented to show that Jupiter could not have been formed as a star of mass 0.001M
and that the observed excess energy is not due to gravitational contraction from an extended, gaseous state. 相似文献
970.
The object of this paper is to investigate the behaviour of electromagnetic field in inhomogeneous cosmological models obtained for viscous fluid distributions. The various particular cases when both the electromagnetic and viscosity are absent, are also discussed. 相似文献