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471.
D. V. Likhodeev Z. I. Dudarov R. A. Zhostkov D. A. Presnov S. M. Dolov K. B. Danilov 《Journal of Volcanology and Seismology》2017,11(6):413-418
This paper presents results from a study of the deep structure of the Elbrus edifice and adjacent areas using geophysical techniques. We confirmed the existence of a shallow magma chamber, derived a more accurate location of the chamber in the host rocks and its characteristic dimensions, and compared new results with known studies. More accurate estimates have been obtained for the temperature at the top of the magma chamber and new evidence is adduced concerning the deep structure of the fluid magmatic systems in the Elbrus volcanic area. 相似文献
472.
D. Vandev K. Danov P. Mateev P. Petrov M. Kartalev N. Trendafilov Z. K. Smith M. Dryer 《Astrophysics and Space Science》1986,120(2):211-221
A study is presented of an algorithm, based on the statistical analysis of interplanetary magnetic field data, for the real-time detection of discontinuities in the solar wind. The analysis is based on the application of a sliding or searching algorithm together with a minimum variance treatment. A demonstration is given for a Pioneer data set from 29 August, 1966. This particular data set was chosen because it has been extensively studied (in terms of the fast forward MHD shock wave) by previous groups who utilized the three-dimensional Rankine-Hugoniot shock equations after identifying the shock on a subjective basis. Our procedure differs in that it is perfectly objective because of its searching technique. For this particular data set we identify the original shock with excellent agreement with the earlier studies of its normal vector, as well as an additional shock and tangential discontinuity, neither of which had been identified previously. 相似文献
473.
The Ginzburg-Landau equations are derived for the magnetic and gluomagnetic gauge fields in the color superconducting core
of a neutron star containing a CFL-condensate of diquarks. The interaction of the diquark CFL-condensate with the magnetic
and gluomagnetic gauge fields is taken into account. The behavior of the magnetic field in a neutron star is studied by solving
the Ginzburg-Landau equations taking correct account of the boundary conditions, including the gluon confinement conditions.
The magnetic field distribution in the quark and hadronic phases of a neutron star is found. It is shown that a magnetic field
generated in the hadronic phase by the entrainment effect penetrates into the quark core in the form of quark vortex filaments
because of the presence of screening Meissner currents.
__________
Translated from Astrofizika, Vol. 50, No. 1, pp. 87–98 (February 2007). 相似文献
474.
475.
Long-term changes in ray populations in the North Sea 总被引:2,自引:3,他引:2
476.
大陆岩石圈有效弹性厚度的计算及其地质意义 总被引:6,自引:1,他引:6
大陆范围内 T e值有很大的范围,不同构造单元有不同的 T e值.T e值的大小与岩石圈的热结构(热年龄)、壳幔耦合等因素有关.同时 T e值和地壳厚度、地表有关矿产的分布、岩石圈地幔的物质组成等也有一定关系. 相似文献
477.
N. K. Choudhary C. S. Agarwal D. K. Sharma 《Journal of the Indian Society of Remote Sensing》1988,16(1):29-39
The Fatehpur Sikri area infringing the western UP, Rajasthan border was investigated for its water supply crisis in respect of poor quality and quantity as well. The study has indicated presence of two parallel quartz reefs running in NE-SW direction. Geohydrological and photogeological studies have revealed the possibility of subsurface extension of quartz reefs. However, this weathered area along reefs is promising water bearing zone. Paleo channels are also marked during studies and the area found suitable for ground water exploitation. A map showing various categories is also presented. 相似文献
478.
A one-dimensional, time-dependent numerical cloud model is used to analyze the factors in the dynamic and thermodynamic equations which lead to a steady-state or nonsteady-state solution for the cloud vertical motion, buoyancy, precipitation, and cloud water fields. ‘Bulk water’ microphysical techniques are used for the cloud, rain, and hail variables. An atmospheric sounding from a severe storm situation is used as initial and environmental conditions, yielding model updrafts of 40 m sec?1 maximum and more than 10 m sec?1 over the entire cloud region. ‘Early conversion’ of the cloud water to rain leads to loading of lower portions of the updraft by rain, the formation of appreciable amounts of hail by freezing of the supercooled rain, and subsequent loading of the middle and upper portions of the updraft so that the updraft erodes throughout the cloud depth and the cloud dissipates, yielding a vigorous rain shower. A delay in the conversion of the cloud water to rain results in a steady-state solution, no rain or hail falling through the updraft. A two-dimensional cloud simulation of this same case shows rain and hail in the upper cloud regions recycled in the two-dimensional flow into the updraft near cloud base and a breakdown of the updraft with resultant rainout (negligible hail reaching the ground). The breakdown of the updraft has profound effects on the temperature field within the cloud, causing the lapse rate to deviate from the steady-state condition and approach the initial environmental conditions. The results emphasize the fact that the local change in temperature (and other dependent variables as well) is not independent of the vertical velocity, in general. This has implications for the interpretation of measurements made within clouds. 相似文献
479.
The new model of the cometary head proposed in papers I and II is developed and applied to comet Burnham. It takes into account the likely existence of a halo of large icy particles surrounding the nucleus. These particles are steadily stripped from the nucleus by evaporating gases. Their terminal velocity and their rate of evaporation set the size of the halo. The existence of the icy halo influences in two ways the photometric characteristics of the coma. This paper establishes the photometric shape of the continuum as reflected by the icy grains, and compares it to the observed continuum of comet Burnham. Paper IV will compare the predictions of the model with the photometric profile of the molecular emission bands of C2, in the same comet. 相似文献
480.
John H. Jones 《Geochimica et cosmochimica acta》1982,46(10):1793-1804
Two very different sets of ratios have been reported for early solar system materials. One group of samples yields high (0.015–0.016) ratios (Podosek, 1970a, 1972; Drozd et al., 1977) and calculations based on another group of analyses yield low ratios (~0.004) (Marti et al., 1977). Recently measured partition coefficients for Pu and Sm are used to evaluate the data of Marti et al. and ratios from other sources are also considered. A low ratio (~0.005) is favored, and some implications of this low ratio to galactic nucleosynthesis and meteorite age dating are briefly discussed. 相似文献