Nuclear activity of NGC 5548 from UBVRI observations during 1990–2000     

V. T. Doroshenko  V. M. Lyuty  N. G. Bochkarev  N. I. Merkulova  S. G. Sergeev  V. V. Vlasyuk  V. P. Mikhailov  O. I. Spiridonova  O. V. Ezhkova  K. N. Grankin  S. Yu. Mel’nikov 《Astronomy Letters》2001,27(11):691-702

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Isotopic Composition of Oxygen and Carbon and Formation Temperature of Accessory Minerals from Evaporitic Sediments in the Pripyat Trough     

Makhnach  A. A.  Kuleshov  V. N.  Pokrovskii  B. G.  Gulis  L. F.  Mikhailov  N. D.  Kolosov  I. L. 《Lithology and Mineral Resources》2002,37(6):536-545

The isotopic composition of oxygen and carbon was studied in accessory carbonates and quartz separated from salts in Upper Devonian halogenous formations of the Pripyat Trough (Belorus). It is established that isotopic characteristics vary in a wide range. Values of ¹⁸O vary in the following range (SMOW): from 18.2 to 29.2 in calcites, from 15.7 to 32.5 in dolomites, and from 17.4 to 27.2 in quartz. Values of ¹³C range from –13.4 to 1.4 in calcites and from –11.1 to 1.7 in dolomites (PDB). Results obtained indicate highly variable isotope-geochemical conditions of sedimentation and early diagenesis during the formation of evaporitic sediments. Accessory minerals were repeatedly formed in a wide temperature range and probably at various stages of the lithogenesis.  相似文献   

Hydrological Regime and Morphodynamics of the Yangtze River Mouth Area   总被引：1，自引：0，他引：1  

Mikhailov  V. N.  Korotaev  V. N.  Mikhailova  M. V.  Congxian  Li  Shuguang  Liu 《Water Resources》2001,28(4):351-363

The features of the hydrological regime, modern morphological structure, fluviomorphological processes, and the history of formation of the Yangtze River mouth area are discussed. The influence of the huge river water and sediment runoff and tides on the hydrological and morphological processes in the Yangtze River mouth is shown. The possible impact of construction of the large waterworks Three Gorges on the hydrological and morphological processes in the Yangtze River mouth is roughly evaluated.  相似文献   

Nickel ores in the Urals     

B. M. Mikhailov 《Lithology and Mineral Resources》2000,35(4):351-364

Based on the analysis of long-term openpit observations of nickel oxide-silicate ores and literature data, characteristic features of the nickel mineralization and raw mineral base for the nickel industry in the Urals are given. The present-day critical situation in this field is outlined and means of the prospecting for high-grade nickel ore deposits in the Urals are proposed. The development of such deposits should be feasible under conditions of the modern market economy.  相似文献   

Hydrological processes in the mouth area of the Hong Ha (Red River)     

M. V. Isupova  V. N. Mikhailov 《Water Resources》2011,38(5):557-570

The main features of hydrological processes taking place in the mouth area of the Hong Ha River in Vietnam are considered. The geographic and hydrological conditions in the Hong Ha River basin and in its receiving water body—the Gulf of Tonkin, South China Sea—are briefly characterized. The main features of the mouth area of the Hong Ha River as a specific geographic object are identified. The hydrological regime of the delta and the nearshore zone of the Hong Ha River are described in detail. Water balance of the delta, runoff water levels and delta inundation, water and sediment runoff distributions over delta branches, and the effect of tides, typhoons, and storm surges on delta regime are considered. Present-day problems of the use and protection of natural resources at the Hong Ha River mouth are briefly discussed.  相似文献   

The hydrological regime and the morphological structure of the Godavari River delta (India)     

V. N. Mikhailov 《Water Resources》2011,38(6):720-734

The major hydrological and geographic characteristics of the Godavari River and the coastal zone of the Bay of Bengal that have their effect on the hydrological regime and the morphological structure of the river delta are considered. The hydrographic, climatic, and environmental conditions in the Godavari delta are described. The specific features of hydrological processes in the delta are considered, including river and bay water mixing and the impact of tropic storms and hurricanes on the delta. The main features of morphological processes in the delta are revealed, including cyclic changes in the delta in Holocene and the dynamics of the channel network and delta coastline in the past 150 years. It is shown that the processes of erosion and retreat of the delta coastline became more active in the late XX century.  相似文献   

Mapping the sun with the RTF-32 radio telescopes     

I. A. Ipatova  A. G. Mikhailov  V. V. Mardyshkin  M. A. Kharinov 《Solar System Research》2006,40(2):169-173

The possibilities of using the RTF-32 radio telescopes of the interferometric QUASAR network for solar observations are investigated. A technique of solar radio mapping with the RTF-32 telescopes is presented. The software developed at the Institute of Applied Astronomy, Russian Academy of Sciences, for reducing such observations is described. The maps of the Sun at 1.35 cm, derived from observations at the Zelenchukskaya observatory November 4–14, 2004, are presented.  相似文献   

Dependence of the Spin of Supermassive Black Holes on the Eddington Factor for Accretion Disks in Active Galactic Nuclei     

M. Yu. Piotrovich  S. D. Buliga  Yu. N. Gnedin  A. G. Mikhailov  T. M. Natsvlishvili 《Astrophysics》2016,59(4):439-448

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Efficiency of Ionospheric Model Correction by Vertical-Incidence Sounding Data from an Ionosonde during Low Sunspot Activity     

Kotonaeva  N. G.  Kolomin  M. V.  Mikhailov  V. V.  Tsybulya  K. G.  Philippov  M. Yu. 《Geomagnetism and Aeronomy》2021,61(1):92-99

Geomagnetism and Aeronomy - Numerical values of the criteria for the efficiency of the determination of the critical frequency of the F2 layer of ionosphere over European Russia are calculated with...  相似文献   

Regularities in the manifestation of earthquake precursors in the ionosphere and near-surface atmospheric electric fields in Kamchatka     

L. P. Korsunova  V. V. Khegai  Yu. M. Mikhailov  S. E. Smirnov 《Geomagnetism and Aeronomy》2013,53(2):227-233

The data of hourly measurements of ionospheric parameters in Petropavlovsk-Kamchatsk are analyzed for the period 1998–2002. In the vertical component of near-surface atmospheric quasistatic electric field Ez, earthquake precursors in the form of anomalous negative bays have been found earlier. In some cases, anomalously high sporadic layer Es, interpreted as an ionospheric precursor of an earthquake, was observed simultaneously with anomalous negative bays in Ez. All these cases were correlated with earthquakes of different magnitudes which occurred with a significant time delay (more than five days) after the precursor appearance. Based on the whole data set (including those for simultaneously measured Es and Ez), empirical dependences linking the prediction time of a precursor, earthquake magnitudes, and the distance from the observation point to the epicenter, are presented. It is shown that these dependences are close to those obtained earlier for long-term earthquake precursors in near-surface geophysical fields of the same seismoactive region. Estimates of the prediction time for earthquake precursors on the boundaries of preparation zones are presented.  相似文献