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31.
The exterior field of the Bianchi type-VI0 metric in the Lyttleton-Bondi universe is considered and an exact cosmological model is presented. Some physical properties of the model are discussed. 相似文献
32.
The spatially-homogeneous and anisotropic cosmological model in self-creation theory of gravitation proposed by Barber, is obtained in the presence of perfect fluid with disordered radiation and the metric is of Bianchi type-V. Some physical properties of the model are discussed. 相似文献
33.
Summary. The extraction of coal seams under built-up structures and especially under water bodies has been a challenge to the miners
due to the potential risk of disturbance to the surface. A number of safety and ground control problems are associated with
the mining operations under water bodies. These can be dealt with through proper planning for the optimization of coal recovery
and systematic strata control investigations. At Godavari khani (GDK) no. 3 incline of the Singareni Collieries Company Limited
(SCCL), two panels namely SS-10/1A and SS-10/1B in no. 1 seam, were identified for extraction under the surface water body
called Janagaon tank. A feasibility study was carried out by the authors for working these panels, and hydraulic sand stowing
method was recommended. Further, strata behaviour monitoring was carried out using remote type geotechnical instruments during
the extraction of pillars in one of the panels. The extraction of the pillars in the experimental panel progressed smoothly
without any strata control problems. The mine management could extract coal reserves in the panel with more than 60% recovery,
which were otherwise unworkable. This paper presents the feasibility of extraction of pillars under the Janagaon tank, and
strata behaviour observations made during the actual extraction. 相似文献
34.
An exact Bianchi type-II vacuum-cosmological model is obtained in the scalar-tensor theory of gravitation proposed by Dunn. The behaviour of the model is discussed. 相似文献
35.
It is shown that the relativistic analogues of vacuum Bianchi type-V cosmological models, in the scalar-tensor theories of gravitation proposed by Ross and Dunn, do not exist. 相似文献
36.
P. R. Reddy N. Venkateswarlu A. S. S. S. R. S. Prasad P. Koteswara Rao 《Journal of Earth System Science》1993,102(3):487-505
An integrated interpretation of the seismic refraction and wide-angle reflection data, geological and structural details,
bore-hole litholog information and gravity particulars along Beliator-Burdwan-Bangaon deep seismic sounding (DSS) profile
in West Bengal basin has helped in getting a crustal density model. This model is consistent with all available surface and
bore-hole geophysical data that can realistically explain the trend, shape and magnitude of gravity data across the West Bengal
basin.
The present exercise pointed out that the thick sedimentary column (with thickening trend towards east), conspicuous lateral
variations in the Moho configuration (with a prominent 40 km wide domal feature covering the eastern part of the stable shelf
and trie western segment of the deep basinal part) coupled with the structural trends in the basement, mid and lower crustal
columns have combinedly contributed to the gravity effect and as such the prominent lateral variations in the Bouguer gravity
anomalies could be mainly attributed to regionally extending causative factors.
The synthesis clearly points out the need to take proper care in selecting the density values as direct conversion of velocities
into densities, adapting well-known conversion formulae, does not always hold good specially in the eastern part of the West
Bengal basin where a huge thickness of sediments (velocities ranging between 4 to 5 km/sec) of high density 2.6 to 2.8 g/cm3 are sandwiched between younger sediments and the crystalline basement. 相似文献
37.
K. Ramadass M. Megharaj K. Venkateswarlu R. Naidu 《International Journal of Environmental Science and Technology》2016,13(12):2863-2874
Four bacterial strains, capable of degrading diesel oil, n-alkanes or hexadecane, were isolated from soils contaminated with petroleum oil and identified. Strains of Pseudomonas sp., Pseudomonas putida TPHK-1 and Pseudomonas aeruginosa TPHK-4, were more efficient in degrading high concentrations of the hydrocarbons than the other two strains, Stenotrophomonas maltophilia TPHK-2 and Acenitobacter sp. TPHK-3. P. putida TPHK-1 exhibited tolerance to very high concentrations of heavy metals such as cadmium, lead, zinc and copper. The innate ability of P. putida TPHK-1, as evidenced by the amplified genes alkB1 and alkB2 that encode alkane hydroxylases, and cat12o and cat23o coding for catechol dioxygenase, in degrading diesel oil in the presence of heavy metals is far greater than that of the strains reported in the literature. Heavy metal tolerance coupled with rapid degradation of hydrocarbons, even at high concentrations, suggests that P. putida TPHK-1 has a great potential in remediating soils contaminated with mixtures of hydrocarbons and heavy metals. 相似文献
38.
39.
S. B. Mishra C. Nagaraj V. Venkateswarlu G. R. Adhikari 《Geotechnical and Geological Engineering》2008,26(4):367-374
With an objective to understand the behaviour of pore water pressure around large underground openings, piezometers were installed
in the rock around the desanding chambers, surge shaft, its drainage galleries, and the transformer cavern of a large hydro-electric
project. The monitored data indicated that the pore water pressure was insignificant in the rock surrounding the desanding
chambers prior to lining. On completion of the concrete lining of the chambers, the maximum pore water pressure was about
50 kPa as the flow of water was restricted. When one of the desanding chambers was charged with water, the piezometers around
it indicated an excessive increase in the pore water pressure due to seepage of water from the chamber. Thus the piezometer
readings were useful in taking appropriate remedial measures. In the surge shaft, higher values of pore water pressure were
recorded on the hill side of the shaft as compared to the valley side. In one of the drainage galleries, the pore water pressure
gradually increased to 450 kPa, which was released by drilling relief holes in the area. In the other drainage gallery, no
significant change in the pore water was recorded. In the transformer cavern, the recorded pore water pressures were within
20 kPa. 相似文献
40.
An exact Bianchi type-I cosmological model in the presence of zero-mass scalar fields is obtained when the source of the gravitational field is a perfect fluid with pressure equal to energy density. Some properties of the model are discussed. 相似文献