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31.
32.
Principles are outlined for the use of sub-satellite soil, air, water, and vegetation samples as an auxiliary source of information in remote sensing studies of vegetation stress caused by air pollution. More specifically, procedures for satellite-synchronous aerial overflights, vegetation transects, water quality measurements, and soil tests are described as a basis for delineating boundaries between areas of vegetation stress and unpolluted areas in an industrialized area in the central Urals. Translated from: Kosmicheskiy monitoring biosfery, Yu. A. Izrael', V. V. Bugrovskiy, and Yu. V. Novikov, eds. Leningrad: Gidrometeoizdat, 1985, pp. 93-99. 相似文献
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V. L. Khokhlova D. V. Vasilchenko V. V. Stepanov I. I. Romanyuk 《Astronomy Letters》2000,26(3):177-191
We present the results of our analysis of magnetic-field configuration and abundance anomalies on the surface of the rapidly rotating, chemically peculiar helium-strong variable B2 V star HD 37776 with unresolved Zeeman components of spectral lines. Simultaneous inversion of the observed Stokes I and V profiles, which realizes the method of Doppler-Zeeman mapping [1], has been applied for the first time. Spectroscopic observations were carried out with the Main stellar spectrograph of the 6-m Special Astrophysical Observatory telescope equipped with a Zeeman analyzer and a CCD array, which allowed spectra in right-and left-hand circularly polarized light to be taken simultaneously at a signal-to-noise ratio S/N≥200 [2]. The profile width of winged spectral lines (reaching 5 Å) is determined by Zeeman line splitting; however, the observed Zeeman components are blurred and unresolved because of the rapid stellar rotation. When solving the inverse problem, we sought for the magnetic-field configuration in the form of a combination of arbitrarily oriented dipole, quadrupole, and octupole placed at the stellar center. The observed Stokes I and V profiles for eight spectral lines of He, O II, Al III, Si III, and Fe III averaged over the visible stellar surface were used as input data. We constructed a model of the magnetic field from the condition of coincidence of magnetic maps obtained from different lines of different chemical elements and from the condition of a minimum profile residual. This model is a combination of centered coaxial dipole and quadrupole with the dominant quadrupole component at 30°<i<50°, β=40°, and a maximum surface field strength H s=60 kG. A comparison of our abundance maps with the field configuration shows that the He concentration is at a maximum in the regions of maximum radial field, while the maximum concentrations of O, Al, Si, and Fe coincide with the regions of maximum tangential field. 相似文献
36.
Tamara I. Zemskaya Tatiayna V. Pogodaeva Olga V. Shubenkova Svetlana M. Сhernitsina Olga P. Dagurova Savelii P. Buryukhaev Bair B. Namsaraev Oleg M. Khlystov Aleksandr V. Egorov Aleksei A. Krylov Gennadii V. Kalmychkov 《Geo-Marine Letters》2010,30(3-4):411-425
Detailed lithological, biogeochemical and molecular biological analyses of core sediments collected in 2002–2006 from the vicinity of the Malenky mud volcano, Lake Baikal, reveal considerable spatial variations in pore water chemical composition, with total concentrations of dissolved salts varying from 0.1 to 1.8‰. Values of methane δ13С in the sediments suggest a biogenic origin (δ13Сmin. ?61.3‰, δ13Сmax. ?72.9‰). Rates of sulphate reduction varied from 0.001 to 0.7 nmol cm?3 day?1, of autotrophic methanogenesis from 0.01 to 2.98 nmol CH4 cm?3 day?1, and of anaerobic oxidation of methane from 0 to 12.3 nmol cm?3 day?1. These results indicate that methanogenic processes dominate in gas hydrate-bearing sediments of Lake Baikal. Based on clone libraries of 16S rRNA genes amplified with Bacteria- and Archaea-specific primers, investigation of microbial diversity in gas hydrate-bearing sediments revealed bacterial 16S rRNA clones classified as Deltaproteobacteria, Gammaproteobacteria, Chloroflexi and OP11. Archaeal clone sequences are related to the Crenarchaeota and Euryarchaeota. Baikal sequences of Archaea form a distinct cluster occupying an intermediate position between the marine groups ANME-2 and ANME-3 of anaerobic methanotrophs. 相似文献
37.
G. Ya. Smolkov V. E. Stepanov V. M. Grigoryev V. G. Banin 《Astrophysics and Space Science》1986,118(1-2):21-30
The Sayan Solar Observatory, the Tunkinskaya Radiophysical Observatory, and the Baikal Astrophysical Observatory of SibIZMIR have been described. Some results of the investigations carried out over the past years have been expounded. Clarifying solar activity mechanisms and the nature of solar magnetic fields, active regions and flares as well as solar wind are their main problems. In the interest of these investigations the Institute has initiated and developed laboratory-scale simulation of plasma processes.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
38.
A new approach to the problem of the formation of galaxy spiral structures having a rotating bar-like nucleus is offered. The process of disk formation due to matter accretion onto the disk is considered in terms of the solution of the key problem on the motion of the matter element in the equatorial plane of the galaxy in the corotation resonance region. It is shown that in the vicinity of unstable libration points high-density regions are formed, which elongate with time following the separatrix shape and forming thereby spiral arms. 相似文献
39.
Philip H. Heckel ;Aleksandr S. Alekseev ;James E. Barrick ;Darwin R. Boardman ;Natalya V. Goreva ;Tatiana N. Isakova ;Tamara I. Nemyrovska ;Katsumi Ueno ;Elisa Villa ;David M. Work 《《幕》》2008,31(3):319-325
We propose that the level at which the conodont species Idiognathodus simulator (Ellison 1941) (sensu stricto) first appears be selected to mark the base of the Gzhelian Stage, because we believe that this is the optimal level by which this boundary can be correlated. This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothems across the Kasimovian-Gzhelian boundary interval among Midcontinent North America and the Moscow and Donets basins of eastern Europe, based on scale of the cyclothems along with several aspects of biostrati- graphy. Outside of these areas, I. simulator (sensu stricto) is known also from other parts of the U.S., and is reported from the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current ammonoid placement of the boundary (first appearance of Shumardites cuyleri), and it is also compatible with certain aspects of the distribution of Eurasian fusulinid faunas (e.g., lectotype ofRauserites rossicus). 相似文献
40.
I. O. Yaroshchuk A. P. Leont’ev A. V. Kosheleva A. A. Pivovarov A. N. Samchenko D. V. Stepanov A. N. Shvyryov 《Russian Meteorology and Hydrology》2016,41(9):629-634
Spatiotemporal variability of the internal gravity waves in the Sea of Japan shelf zone (in the Peter the Great Bay) is analyzed basing on the results of the experimental data processing. It is shown that, as for autumn water structure, the tidal internal waves moving towards the coast are transformed due to the non-linear effects and may reach significant amplitudes (of about 10 meters). Such waves are usually referred to as strongly non-linear. The main characteristics of such intense waves were estimated. An example of the disintegration of solitary temperature depression into the package of short-period intense internal waves is given. 相似文献