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141.
U, B, V photoelectric observations of the eclipsing binary system DX Aqr, secured in 1981, have been presented. Present results, when compared with earlier ones (cf. Srivastava and Sinha, 1985), suggest that the features of the system are changing. Some new features are reported.  相似文献   
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We have studied the relationships between the brightness, color, and emission-line profiles for the classical T Tauri star RW Aur, which displays an intense emission spectrum and signs of accretion and outflow. Spectral and photometric observations carried out from 1995 to 1999 have been analyzed in the framework of magnetospheric accretion concept, where the brightness of the star depends on the level of the non-photospheric continuum (veiling), which, in turn, depends on the accretion rate. We found that (1) the equivalent widths and profiles of broad emission lines vary independently of the brightness of the star, the brightness and color variations are due primarily to absorption in dust clouds formed by the disk wind; (2) at times when the accretion in the line of sight becomes stronger, all broad emission lines are weakened substantially due to the asymmetry of the magnetosphere and screening of the radiating region; (3) the periodic variations of the U-B and B-V color indices are due to the variable contribution of broad emission lines in the photometric bands; (4) the veiling of the photospheric spectrum is not correlated with either the brightness of the star or the intensity of the accretion components.  相似文献   
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Doklady Earth Sciences - Comparative characteristics of gold minerals from gabbro of the Uralian Platinum Belt based on the author’s (Kumba massif, Serebryanskii Kamen massif, and Volkovskoe...  相似文献   
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The authors, drawing upon the work of Hagerstrand and others in the field of spatial diffusion modeling, develop a model for predictive mapping of the spread of disease based on the Monte Carlo method. Analysis of this particular model showed high coefficients of correlation between mathematical probability estimates of times of origin for epidemics in particular territorial units and their densities of population and population potentials. Translated from: Izvestiya, Vsesoyuznogo Geograficheskogo Obshchestva, 1986, No. 1, pp. 67-74.  相似文献   
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Doklady Earth Sciences - A detailed structural study showed that the Mesoproterozoic Karadjilga granite–gneiss massif of the Kyrgyz North Tianshan represents a sheet intrusion, concordant to...  相似文献   
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The Mukun Group represents a thick (>750 m) complex of terrigenous features sediments in the lower part of the Riphean sedimentary cover of the Anabar region was formed on the spacious cratonic block. The complex is remarkable for its pure quartzarenitic composition. The facies analysis with emphasis on the genetic interpretation of various sedimentary structures revealed three facies associations in its sedimentary succession: alluvial, eolian-fluvial, and fluvial-sabkha. It is shown that sedimentary material was transported into the terminal basin by a braided system of permanent rivers. Relationships between the eolian and fluvial components in the single sedimentation system of the Mukun paleobasin is considered in line with the proposed model, according to which alternation of long periods with the eolian and fluvial sedimentation was controlled by tectonics.  相似文献   
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