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41.
O. N. Andreev S. A. Antonenko V. M. Gotlib G. V. Zakharkin V. M. Linkin A. N. Lipatov V. S. Makarov B. K. Khairulin L. I. Khlyustova 《Solar System Research》2010,44(5):438-443
The exploration of planet moons and minor bodies (Avduevskii et al., 1996) is a basic task for comprehending the nature of
the processes occurring in our Solar System. Knowing the current state of the moons, we can better describe their past and
look into the future. This knowledge is important, first of all, for understanding the origin of the Solar System. Interest
in the Martian moon Phobos has been displayed during recent decades. The interest is caused by some questions to which there
have been no answers up until now (Sagdeev et al., 1988; 1989). For example, there is a question regarding the origin of the
moon: whether it is an asteroid captured by Mars’ gravitational field or it is an accumulated body in the Martian orbit. In
connection with this, it is interesting to conduct studies aimed at answering this question. If Phobos appears to be an asteroid,
then investigations regarding the chemical and isotopic compositions of the moon as the primary matter of the Solar System
as well as its evolution are of great interest. 相似文献
42.
A. M. Asavin L. I. Anikeeva V. A. Kazakova S. I. Andreev D. A. Sapozhnikov I. A. Roshchina L. N. Kogarko 《Geochemistry International》2008,46(12):1179-1205
A collection of layered ferromanganese ores (27 samples) from the Atlantic and Pacific oceans was studied. Trace element and PGE contents were determined layer-by-layer (up to 10 microlayers) in 13 of these samples.The trace, rare earth, and platinum group element distributions, including their layer-to-layer variations, were compared in hydrogenic and hydrothermal crusts from different regions. It was found that the main PGE variations (by a factor of 10–50) are related to their layer-to-layer variations within a given ore field.The distributions of PGE and trace elements are strongly heterogeneous, which is related, first, to different contents of the elements in the layers of different age in ferromanganese crusts (FMC) and, second, to the observed regional heterogeneity and influence of hydrothermal fluids. Geochemical data indicate that CFC formation was mainly caused by the hydrochemical precipitation of material from seawater. This process was accompanied by diagenetic phenomena, water-rock interaction, and influence of volcanic and hydrothermal sources. 相似文献
43.
V. Andreev 《Boundary-Layer Meteorology》1973,3(3):273-283
The changes with timet of a temperature deviation δT(t,α) and of a vertical velocityW i(t,α) of an isolated dry thermal have been investigated theoretically. Solutions for the functionW i(t, α) have been derived for stable and unstable environmental stratifications. Comparing these solutions with the corresponding ones for the rise of an adiabatic thermal yield some interesting conclusions. Firstly, there is the evident relation between the rate of entrainment of environmental air (expressed by the parameter α=(1/M i) dM i/dz whereM i is the mass of the thermal) and the vertical velocity of the thermal: an increase in α decreases the velocity. Two similar thermals in stably stratified surroundings, one of them moving adiabatically (α=0) the other nonadiabatically (α>0), would rise for the same length of timet 2=π/N, whereN is a typical Brunt-Väisälä frequency, but with different velocities and to different heights: the ascent timet 2 depends only on environmental parameters. In an unstable stratification, the vertical non-adiabatic velocity of the thermal, instead of increasing without limit, tends towards a finite asymptotic velocity $$W_t (\infty ) = (\sqrt { - \mathcal{N}^2 } )/\alpha $$ the value of which depends upon both the stratification of the surroundings and upon the entrainment rate α. In a real atmosphere, where additional retarding forces exist, the motion will certainly be damped. 相似文献
44.
This paper analyzes demographic data (the time series of the number of births and deaths for over 50 years in the 20th and
21st centuries). The properties of the time series are revealed, and some of them are explained. A comparison of data for
men and women has resulted in the revelation that seasonal changes for women are more strongly evident than for men. The possible
causes for the differences between the time series of the number of deceased men and women are discussed. 相似文献
45.
V. N. Soyfer V. A. Goryachev D. V. Andreev I. R. Barabanov A. P. Borisov Yu. N. Zhukov E. A. Yanovich 《Oceanology》2010,50(4):600-612
A methodology of experimental simulation of the state of spent nuclear fuel that is situated on the sea bottom as a result
of some catastrophes or dumping is developed. Data on long-term (more than 2000 days) experiments on the estimation of the
85Kr and 137Cs release rate from spent nuclear fuel (fragments of irradiated UO2 pellets) were first obtained; these estimates prove the correctness of the hypothesis put forward by us in the early 1990s
concerning an earlier 85Kr release (by one order of magnitude higher than that of 137Cs) as compared to other fission fragments in the case of the loss of integrity of a fuel containment as a result of corrosion
on the sea bottom. The method and technique of the onboard 85Kr and 137Cs sampling and extraction (as well as the sampling of tritium, a product of triple 235U fission) and their radiometric analysis at coastal laboratories are developed. Priority data on the 85Kr background in the bottom layers of the Barents and Kara Seas and the 137Cs and 3H in these seas (state of 2003) are presented. Models necessary for the estimation of the dilution of the fission products
of spent nuclear fuel and their transport on the bottom in accident and dumping regions are developed. An experimental method
for the examination of the state of spent nuclear fuel on the sea bottom (1 expedition each 2–3 years) by the 85Kr release into the environment (a leak tracer) is proposed; this release is an indicator of the destruction of a fuel containment
and the release of products of spent nuclear fuel in the case of 235UO2 corrosion in sea water. 相似文献
46.
Andreev Andrey G. Budyansky Maxim V. Khen Gennady V. Uleysky Michael Yu. 《Ocean Dynamics》2020,70(5):593-602
Ocean Dynamics - To study the water dynamics in the western Bering Sea, the time series of geostrophic velocities derived from satellite altimetry, Global total current (Copernicus Globcurrent)... 相似文献
47.
A previously developed model of the high-latitude ionosphere is used to calculate the distribution of the ionospheric parameters in the polar region. A specific method for specifying input parameters of the mathematical model, using the experimental data obtained by the method of satellite radio tomography, is used in this case. The spatial distributions of the ionospheric parameters characterized by a complex inhomogeneous structure in the high-latitude region, calculated with the help of the mathematical model, are used to simulate the HF propagation along the meridionally oriented radio paths extending from middle to high latitudes. The method for improving the HF communication between a midlatitude transmitter and a polar-cap receiver is proposed. 相似文献
48.
Andreev V. E. Efimov A. I. Samoznaev L. N. Chashei I. V. Bird M. K. 《Solar physics》1997,176(2):387-402
A statistical study of Faraday rotation fluctuations (FRF) has been performed using polarization angle data of S-band (f = 2.3 GHz) radio spacecraft signals. The measurements were recorded during the recurring superior conjunctions of the Helios probes, during which the solar proximate point of the radio ray path reached heliocentric distances between 3 and 34 R. The most commonly found temporal FRF spectra are power laws with an average spectral index 1.5 over the frequency range from 1 mHz < v < 10 mHz. The FRF variance decreases with heliocentric distance, the falloff exponent being 8 for R < 6 R and 3 for distances 8 < R < 6 R < 16 R. The results are interpreted under the assumption that the FRF are produced by Alfvén waves propagating in the coronal plasma. For the applicable range of heliocentric distances it is shown that Alfvén waves are in a regime of free propagation and probably transfer much of their energy to the kinetic energy of the solar wind. The spatial power spectrum of magnetic field fluctuations is inferred to be strongly anisotropic, the irregularities extending along the background magnetic field with axial ratios of the order of 10. 相似文献
49.
Andrey G. Andreev Maxim V. Budyansky Michael Yu. Uleysky Sergey V. Prants 《Ocean Dynamics》2018,68(11):1503-1514
Large canyons incise the shelf break of the eastern Bering Sea to be preferred sites of the cross-shelf exchange. The mesoscale eddy activity is particularly strong near the shelf-break canyons. To study the mesoscale dynamics in the Navarin Canyon area of the Bering Sea, the time series of velocities derived from AVISO satellite altimetry between 1993 and 2015, drifters, Argo buoys, and ship-borne data are analyzed. We demonstrate that the strength of anticyclonic eddies along the shelf edge in spring and summer is determined by the wind stress in March–April. The increased southward wind stress in the central Bering Sea forced a supply of low-temperature and low-salinity outer shelf water to the deep basin and formation of the anticyclonic mesoscale circulation seaward of the Navarin Canyon. Enhanced northwestward advection of the Bering Slope Current water leads to increase in an ice-free area in March and April and increased bottom-layer temperature at the outer shelf. The strong (weak) northwestward advection of the eastern Bering Sea waters, determined by eastern winds in spring, creates favorable (unfavorable) conditions for the pollock abundance in the western Navarin Canyon area in summer. 相似文献
50.