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81.
In the present work we study (i) the charged black hole in Einstein–Gauss–Bonnet (EGB) theory, known as the Einstein–Maxwell–Gauss–Bonnet
(EMGB) black hole and (ii) the black hole in EGB gravity with a Yang–Mills field. The thermodynamic geometry of these two
black hole solutions has been investigated, using the modified entropy in Gauss–Bonnet theory. 相似文献
82.
83.
84.
Farook Rahaman Mubasher Jamil Mehedi Kalam Kaushik Chakraborty Ashis Ghosh 《Astrophysics and Space Science》2010,325(1):137-147
We investigate the spacetime of anisotropic stars admitting conformal motion. The Einstein field equations are solved using
different ansatz of the surface tension. In this investigation, we study two cases in details with the anisotropy as: (1)
p
t
=n
p
r
, (2)
-p_r=(+c_2)p_{t}-p_{r}=\frac{1}{8\pi}(\frac{c_{1}}{r^{2}}+c_{2})
where, n, c
1 and c
2 are arbitrary constants. The solutions yield expressions of the physical quantities like pressure gradients and the mass. 相似文献
85.
Natural Hazards - Scaled energy, apparent stress, seismic moments, stress drops and corner frequencies are measured through the Levenberg–Marquardt nonlinear inversion modeling of S-wave... 相似文献
86.
In this work, we study universe bounded by apparent horizon as an irreversible thermodynamical system. Using the non equilibrium thermodynamical technique, the modified entropy variation on the apparent horizon has been evaluated in general. Two dark energy models are presented and results are analyzed. 相似文献
87.
Summary Elastic wave propagation problem has been studied in the composite medium — a gravitating liquid layer overlying an elastic half-space. Assuming moving normal pressure load on the free surface, an attempt has been made to study the order of disturbance on the earth's surface. In the discussion asymptotic values of the displacement, components have been considered for small values of the parameter. 相似文献
88.
Hilly or mountainous terrain occupies around 12% of the area of Bangladesh.Natural resources associated with Bangladesh’s hill are forest resources,biodiversity,minerals,and agricultural crops.Natural resources have been exploited in the recent four decades due to excessive clearing of hill forest cover,resulting in loss of species richness, impacts related to increased water flow variability, increased hill slope erosion and flooding intensity, and a gradual decrease in the extent of hill area in Bangladesh.This review explores the major causes and effects of depletion of natural resources by linking drivers,pressures and the related impacts.A review has been conducted to structure the effects on the hilly areas and describe the responses to minimize them in the associated DPSIR framework.Population growth has been identified as a major driver contributing to high deforestation rates.This may negatively effect agricultural productivity and increase the frequency of serious flooding.Slash and burn cultivation also impacts the regeneration of evergreen forests,which may accelerate soil erosion. Due to this and other factors,local people are facing a deficits of natural resources(food,fodder,fuel wood and water),which exacerbates the effects of poverty. Future research should try to facilitate decision making for sustainable utilization of natural resources management in the hilly areas of Bangladesh. Additional conservation measures should be developed to increase the resilience of ecosystems at national and regional levels. 相似文献
89.
Michael E. Lipschutz Swarajranjan Biswas Harry Y. McSween 《Geochimica et cosmochimica acta》1983,47(2):169-179
We report petrologic data and contents of Ag, Bi, Cd, Co, Cs, Ga. In, Rb, Se, Te, Tl and Zn-trace elements spanning the volatility/mobility range-in light and dark portions of H chondrite regolith breccias and L chondrite fragmental breccias. The chemical/petrologic characteristics of H chondrite regolith breccias differ from those of non-brecciated chondrites or fragmentai breccias. Petrologic characteristics and at least some trace element contents of H chondrite regolith breccias reflect primary processes; contents of the most volatile/mobile elements may reflect either primary or secondary processing, possibly within layered H chondrite parent object(s). Chemical/petrologic differences existed in different regions of the parents). Regolith formation and gardening and meteoroid compaction were not so severe as to alter compositions markedly. 相似文献
90.
J. Thiede K. Cehak Stephen G. Warren A. Zaporozec Karl W. Butzer H. Th. Verstappen Robert A. Creelman Jan Lundqvist Xavier de Planhol G. Kunkel Wolf Tietze P. G. Söhnge K. U. Sirinanda Owen J. Furuseth Catharine Nagashima T. Pioro Asit K. Biswas J. -P. Moreau Hildegard Binder Johnson 《GeoJournal》1980,4(1):91-96