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Neeraj Pant 《Astrophysics and Space Science》1996,240(2):187-193
We present a new class of spherically symmetric exact solutions of the general relativistic field equations. These solutions describe perfect fluid balls with infinite central pressure and central density though their ratio is finite. A member of the class has been studied in detail from which we have constructed a model of causal fluid ball with constant sound speed. 相似文献
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Electromagnetic induction by the equatorial electrojet 总被引:1,自引:0,他引:1
R. G. Rastogi 《Geophysical Journal International》2004,158(1):16-31
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Bindhyachal Pandey Deo Brat Pathak Neeraj Mathur Anand K. Jaitly Alok K. Singh Prakash K. Singh 《Journal of the Geological Society of India》2018,92(4):427-434
In the present investigation, an attempt has been made to explore the possibility of hydrocarbon prospects in the carbonaceous shale deposits of Spiti and Chikkim formations exposed in the Spiti valley of the Tethys Himalaya. Twenty samples, collected from successive levels of these litho-units, have been subjected to maceral analysis, Rock-Eval Pyrolysis and six samples to Fourier Transform Infra-red Spectroscopy (FTIR) and nuclear magnetic resonance (NMR) analyses. The study reveals the presence of mainly kerogen-III type of organic matter but some of the shale samples have shown a good amount of total organic carbon (TOC) to the tune of 3.19% which is sufficient to produce hydrocarbon. The results indicate the presence of methane occurring as free and fixed hydrocarbon in the shale samples. Few levels are especially rich in hydrocarbon. They have shown encouraging results with potential for generating liquid as well as lighter hydrocarbon. The data is also supported by the FTIR and NMR studies. 相似文献
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Anticipating the scale invariance of rock fracturing processes, we applied Keilis-Borok’s algorithm M8, originally designed
for identifying times of increased probability (TIPS) of occurrence of strong earthquakes (M < 8.0), retrospectively to Koyna
earthquakes which occurred in the region after the impoundment of the Shivaji Sagar reservoir in 1962. The algorithm which
enables diagnosis of TIPS from the 7th year onwards after the commencement of the earliest available data set showed that
the 5.3 magnitude earthquake of 20 September 1980 indeed occurred within a time of increased probability. This result, apart
from its potential application to recognizing future TIPS in the region, points to selfsimilarity between the premonitory
patterns of natural and induced earthquakes and to scale-invariant nature of their processes. Further, a typical precursory
rise in seismicity followed by a relative quiescence was also found to precede all the three larger earthquakes of the sequence. 相似文献
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The paper presents the first results on the behaviour of solar quiet-day variations of the geomagnetic field components at Gulmarg. Combining the data from Russian stations in the same longitude belt, the annual average daily variations are calculated which show, in the horizontal component (H), a reversal of phase between Gulmarg and Tashkent. Studying the Sq-variations at Gulmarg separately for the three seasons, the daily variation of H duringd-months is predominantly diurnal in character with the maximum before noon. Duringe-months, and more so inj-months, daily variation of the H field is predominantly semidiurnal in character with minimum around 08–09 hr LT and maximum around 14 hr LT consistently during 1978, 1979 and 1980. These features of the Sq at Gulmarg are suggested to be due to the deformations of the current loops caused by the changing latitude of focus during the course of the day. 相似文献
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R. G. Rastogi 《Pure and Applied Geophysics》1958,40(1):145-156
Summary The mean monthly noon critical frequencies of theE andF1 layers of the ionosphere at a number of stations in different latitudes and their variation with sunspot number have been studied in this paper. It is found that while theE layer approximates to a chapman region, theF1 layer is markedly affected by other agenices, somewhat similar toF2. In high sunspot years,foF1 shows two maxima at middle latitudes with a minimum at the equator. 相似文献