Water resources of the Northern Economic Region of Russia: The state and use     

N. N. Filatov  A. V. Litvinenko  M. S. Bogdanov 《Water Resources》2016,43(5):779-790

The issues of water availability and water resources use in the Northern Economic Region are considered for the region as a whole and for the RF constituent entities it embraces.  相似文献   

Geochemistry of organic matter in bottom sediments of the Ashadze hydrothermal field   总被引：3，自引：0，他引：3  

I. P. Morgunova  V. N. Ivanov  I. V. Litvinenko  V. I. Petrova  T. V. Stepanova  G. A. Cherkashev 《Oceanology》2012,52(3):345-353

Comparative studies of the composition and distribution of the dispersed organic matter (DOM) were performed for the bottom sediments from active areas of the Ashadze hydrothermal field (the Mid-Atlantic Ridge, 13° N) and for background sediments from the area treated (sampled during the cruises of R/V Professor Logachev in 2003 and 2007). The content of hydrocarbons (HCs) in the hydrothermal samples is about 20 times as high as the background values. The HCs composition includes both low-transformed (isoprenoids, hopenes, ββ-hopanes, and ααα27R-steranes) and geologically mature chemofossils (C₁₆-C₃₅ n-alkanes, geohopanes, moretanes, and polyaromatic hydrocarbons). The polyaromatic hydrocarbons (PAHs) are mainly represented by phenanthrene and its alkyl homologues, i.e., by possible products of the diagenetic transformation of biogenic precursors. The results obtained point to the mixed genesis of the hydrothermal DOM, which is caused first by the diversity of the biota composition in the considered region, as well as by the specificity of the processes of the DOM’s maturing under the extreme environmental conditions.  相似文献   

The role of volcanic ash in formation of soil and vegetative cover in the present-day explosive volcanism area     

L. V. Zakharikhina  Yu. S. Litvinenko 《Journal of Volcanology and Seismology》2008,2(1):16-29

By the example of an area near the active Karymskii Volcano (on the eastern coast of Kamchatka) it is shown that under conditions of regular supply of pyroclastic material on the diurnal surface, organic soil matter transforms very slowly and mobile trace elements of newly fallen volcanic ashes are the major plant nutrition source. Geochemical specialization of the studied area is characterized by lower concentrations of most trace elements relative to their clarkes for soils and by an excess of trace element contents over the clarkes for living matter in plants. Newly fallen ashes are enriched in mobile trace elements, which in dissolved form pass into adjacent media due to hypergene geochemical processes.  相似文献   

Heavy Ion Abundances in Impulsive Solar Flares: Influence of Pre-Acceleration in a Current Sheet     

Yuri E. Litvinenko 《Solar physics》2002,205(2):341-349

Competition between stochastic energy gains and collisional energy losses is known to lead to preferential acceleration of heavy ions in flare loops. Ion acceleration in a reconnecting current sheet is shown to mitigate the influence of collisional energy losses on stochastic particle acceleration in impulsive solar flares. This effect decreases the sensitivity of the resulting abundance ratios on initial ion charge states. The resulting abundances are determined by the fact that the energy loss rate falls off rapidly with increasing energy. As an example, the expected Fe/O enhancement ratios are computed and shown to be comparable with those observed with ACE SEPICA in several impulsive flares in 1998. One consequence of the model is that the preferential acceleration of heavy ions can occur only when the plasma gas pressure is large enough, m _e/m _p, which may explain the observed correlation between the heavy ion enrichment and selective ³He acceleration in impulsive flares.  相似文献   

Internal structure of simple S-bursts of Jovian decameter-wavelength emission     

G. V. Litvinenko  V. V. Vinogradov  H. O. Rucker  V. E. Shaposhnikov 《Astronomy Reports》2007,51(5):394-400

The fine internal structure of fundamental Jovian decameter-wavelength millisecond outbursts (S-bursts) is studied. Broadband data obtained with the Waveform Receiver (WFR) on the UTR-2 decameter radio telescope have been analyzed using wavelet transforms. The millisecond S-bursts have a complex internal pulse microstructure, whose parameters are presented. Our results offer new prospects for understanding Jovian decameter-wavelength emission.  相似文献   

Mechanism of thermonuclear burning propagation in a helium layer on a neutron star surface: A simplified adiabatic model     

V. A. Simonenko  D. A. Gryaznykh  I. A. Litvinenko  V. A. Lykov  A. N. Shushlebin 《Astronomy Letters》2012,38(4):231-237

Some thermonuclear X-ray bursters exhibit a high-frequency (about 300 Hz or more) brightness modulation at the rising phase of some bursts. These oscillations are explained by inhomogeneous heating of the surface layer on a rapidly rotating neutron star due to the finite propagation speed of thermonuclear burning. We suggest and substantiate a mechanism of this propagation that is consistent with experimental data. Initially, thermonuclear ignition occurs in a small region of the neutron star surface layer. The burning products rapidly rise and spread in the upper atmospheric layers due to turbulent convection. The accumulation of additional matter leads to matter compression and ignition at the bottom of the layer. This determines the propagation of the burning front. To substantiate this mechanism, we use the simplifying assumptions about a helium composition of the neutron star atmosphere and its initial adiabatic structure with a density of 1.75 × 10⁸ g cm⁻³ at the bottom. 2D numerical simulations have been performed using a modified particle method in the adiabatic approximation.  相似文献