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21.
Alla BRYANSKAYA Alexey ROZANOV Tatyana MALUP Taisiya ALESHINA Elena LAZAREVA Oxana TARAN Tatyana GORYACHKOVSKAYA Vladimir IVANISENKO Sergey PELTEK 《《地质学报》英文版》2014,88(Z1):61-62
正Salt Lake is one of the lakes in the system,consisting of a huge amount of salt and bitter-salty lakes in Novosibirsk Oblast and Altai Krai.These lakes are unique and highly unstable systems where the parameters of geochemical 相似文献
22.
Diurnal and semiannual variations in geomagnetic activity are considered. We prove that there exists an inner magnetospheric source of magnetic activity, which depends on the angle φ between the planes of the magnetotail plasma sheet and the geomagnetic equator. It is shown that diurnal and semiannual variations in magnetic activity result from changes in the value of this angle. 相似文献
23.
Makarov V. I. Stoyanova M. N. Sivaraman K. R. 《Journal of Astrophysics and Astronomy》1982,3(4):379-382
Ring-like filaments have been detected on the spectroheliograms in the H-alpha line. Inside these filaments the magnetic field
flux has a predominant polarity. Some of the dark filaments are connected by filament channels which can be seen at the limb
either as (a) weak prominences or (b) dense low chromospheric features or (c) multi-channel system of matter flow between
two prominences or (d) common quiescent prominences. The filament and the filament channel together form a continuous closed
contour and outline the region of thef polarity particularly at the beginning of the solar cycle. The change in sign of the polar field of the Sun is associated
with the drift of the filament band to high latitudes. 相似文献
24.
Lockwood, Stamper, and Wild (1999) argued that the average strength of the magnetic field of the Sun has doubled in the last 100 years. They used an analysis of the geomagnetic index aa. We calculated the area of polar zones of the Sun, A
pz, occupied by unipolar magnetic field on H synoptic magnetic charts, following Makarov (1994), from 1878 to 2000. We found a gradual decrease of the annual minimum latitude of the high-latitude zone boundaries, 2m, of the global magnetic field of the Sun at the minimum of activity from 53° in 1878 down to 38° in 1996, yielding an average decrease of 1.2° per cycle. Consequently the area of polar zones A
pz of the Sun, occupied by unipolar magnetic field at the minimum activity, has risen by a factor of 2 during 1878–1996. This means that the behavior of the index aa and consequently the magnetic flux from the Sun may be explained by an increase of the area of polar caps with roughly the same value of the magnetic field in this period. The area of the unipolar magnetic field at the poles (A
pz) may be used as a new index of magnetic activity of the Sun. We compared A
pz with the aa, the Wolf number W and A* -index (Makarov and Tlatov, 2000). Correlations based on `11-year' averages are discussed. A temperature difference of about 1° between the Maunder Minimum and the present time was deduced. We have found that the highest latitude of the polar zone boundaries of the large-scale magnetic field during very low solar activity reaches about 60°, cf., the Maunder Minimum. It is supposed that the 2m-latitude coincides with the latitude where r=0, with (r,) being the angular frequency of the solar rotation. The causes of the waxing and waning of the Sun's activity in conditions like Maunder Minimum are discussed. 相似文献
25.
Astronomical Council, USSR Academy of Sciences; Urals State University. Translated from Astrofizika, Vol. 28, No. 2, pp. 405–417, March–April, 1988. 相似文献
26.
We perform the bifurcation analysis of the Kepler problem on
and
. An analog of the Delaunay variables is introduced. We investigate the motion of a point mass in the field of a Newtonian
center moving along a geodesic on
and
(the restricted two-body problem). For the case of a small curvature, the pericenter shift is computed using the perturbation
theory. We also present the results of numerical analysis based on an analogy with the motion of a rigid body. 相似文献
27.
We report a list of groups consisting of dwarf galaxies only. The sample contains 126 objects, mainly combined in pairs. The
most populated group contains six dwarf galaxies. The majority of systems considered reside in the low-density regions and
evolve unaffected by massive galaxies. The characteristic sizes and velocity dispersions of groups are 30 kpc and 11 km/s,
respectively. They resemble the associations of dwarf galaxies, but are more compact. On the whole, groups and associations
form a continuous sequence. Alike the associations, our groups possess high mass-to-luminosity ratios, what is indicative
of a large amount of dark matter present in these systems. 相似文献
28.
I. D. Karachentsev V. E. Karachentseva O. V. Melnyk A. A. Elyiv D. I. Makarov 《Astrophysical Bulletin》2012,67(4):353-361
This paper is the first of a series considering the properties of distribution of nearby galaxies in the low density regions. Among 7596 galaxies with radial velocities V LG < 3500 km/s, absolute magnitudes M K < ?18?4, and Galactic latitudes |b| > 15° there are 3168 field galaxies (i.e. 42%) that do not belong to pairs, groups or clusters in the Local universe. Applying to this sample the percolation method with a radius of r 0 = 2.8Mpc, we found 226 diffuse agglomerates with n ?? 4 number of members. The structures of eight most populated objects among them (n ?? 25) are discussed. These non-virialized agglomerates are characterized by amedian dispersion of radial velocities of about 170 km/s, the linear size of around 6 Mpc, integral K-band luminosity of 3 × 1011 L ??, and a formal virial-mass-to-luminosity ratio of about 700M ??/L ??. The mean density contrast for the considered agglomerates is only $\left\langle {\Delta n/\bar n} \right\rangle $ ?? 5, and their crossing time is about 30?C40 Gyr. 相似文献
29.
This contribution deals with the properties of small-scale magnetic elements at the polar caps of the Sun. Spectro-polarimetric observations, obtained with high spatial resolution with the Gregory Coudé Telescope at the Observatorio del Teide on Tenerife, were analysed. We find, though with limited data sets, that polar faculae differ in two aspects from faculae of the network in non-active regions near the equator (equatorial faculae): (1) Polar faculae appear to have the same magnetic polarity as the general polar magnetic field. Presumably, the latter is rooted in the small-scale faculae. The equatorial faculae show both magnetic polarities. (2) Polar faculae, with a size of 3.5 ± 1.3, are larger than equatorial faculae with 2.1 ± 0.4. Yet as for equatorial faculae, polar faculae possess kilogauss magnetic fields. 相似文献
30.
O. I. Bazhenova A. A. Cherkashina D. V. Kobylkin S. A. Makarov K. E. Vershinin 《Geography and Natural Resources》2017,38(2):154-164
A conjugate analysis of the processes of morphogenesis and sedimentation within small fluvial basins of Dauria revealed a rhythmic character of change of the Holocene processes which are combined into cycles of a different hierarchical level. It is shown that each cycle begins with an extreme phase of intense fluvial drift and delivery of matter from the system. The fluvial horizons comprise the lower part of deposits of the Holocene macrocycle in the Vesnyanka pad’ (a valley without a permanent watercourse). A disastrous fluvial drift was recorded repeatedly for the period 7–8.5 cal. ka and at the transition time from the Atlantic to Subboreal time. A normal zonal phase of integration of matter within the basins is exhibited by buried humus horizons of soils which give clear evidence of 1800-year cycles. A regional development in Dauria is recorded for the soils with the age of about 8, 6.4 and 4.6 as well as 1.2–1.4 cal. ka. The upper part of the deposits of each cycle is characterized by aeolian horizons of extreme arid phases. The profiles of proluvial trails are indicative of 130-year cycles. Based on results from studying buried soils, data of pollen analysis and radiocarbon dating of the deposits, we determined an enhancement in climate aridization for the last 10 ka and, in general, a decreased of the sedimentation and morphogenesis rate. 相似文献