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1.
A comparative geochemical study of rare-metal granitoids with various fluorine-bearing minerals (fluorite, topaz, and cryolite)
was carried out. It was shown that these rocks correspond to both plumasitic and agpaitic geochemical types. The fluorite-,
topaz-, and cryolite-bearing granites of these geochemical types are distinctly different in geochemical parameters and the
character of magmatic evolution. These differences are related to the composition of initial magmas and their sources. Rare-metal
granitoids with fluorine-bearing minerals compose small massifs, stocks, and dike swarms. Their formation is independent of
the composition and age of the country rocks or geologic structures where they occur.
Original Russian Text ? V.S. Antipin, E.A. Savina, M.A. Mitichkin, 2006, published in Geokhimiya, 2006, No. 10, pp. 1040–1052. 相似文献
2.
Sergei V.Antipin Ignacio Becker AlexANDer A.Belinski Darya M.Kolesnikova Karim Pichara Nikolay N.Samus Kirill V.Sokolovsky Alla V.Zharova Alexandra M.Zubareva 《天文和天体物理学研究(英文版)》2018,(8)
Using 172 plates taken with the 40-cm astrograph of the Sternberg Astronomical Institute(Lomonosov Moscow University) in 1976–1994 and digitized with a resolution of 2400 dpi, we discovered and studied 275 new variable stars. We present the list of our new variables with all necessary information concerning their brightness variations. As in our earlier studies, the new discoveries show a rather large number of high-amplitude Delta Scuti variables, predicting that many stars of this type remain not detected in the whole sky. We also performed automated classification of the newly discovered variable stars based on the Random Forest algorithm. The results of the automated classification were compared to traditional classification and showed that automated classification was possible even with noisy photographic data. However, further improvement of automated techniques is needed, which is especially important when considering the very large numbers of new discoveries expected from all-sky surveys. 相似文献
3.
D. M. Kolesnikova L. A. Sat K. V. Sokolovsky S. V. Antipin A. A. Belinskii N. N. Samus’ 《Astronomy Reports》2010,54(11):1000-1018
In the course of a program to digitize the astronomical plates of the Sternberg Astronomical Institute’s plate stacks, we
are developing algorithms for searching for new variable stars and studying them using digitized photographic plates. We have
discovered and studied 480 new variable stars in a 10° × 10° field of view centered on 66 Ophiuchi. The digitized plate negatives
used are from the 40-cm astrograph, and are 30 × 30 cm in size. These stars include three new Cepheids of the Galaxy’s spherical
component, 157 eclipsing binaries, 11 high-amplitude δ Scuti stars (HADSs), 144 RR Lyrae stars, 110 irregular variables (109 LB and one white star), and 55 semi-regular red variables.
New important information has been obtained for 43 known variables, which we have classified and derived or improved their
light elements; an erroneous identification of the Mira V404 Oph has been corrected. We have also identified more than 50
suspect brightness variables; a program of CCD observations of these suspected variables has been initiated. Our discoveries
of new variable stars were performed in a star field with a large number of known variables, detected earlier photographically
or using CCD techniques. The discovery of hundreds of new variables in a well-studied region of sky demonstrates that archive
photographs possess a large information potential that has remained unrealized. 相似文献
4.
K. V. Sokolovsky S. V. Antipin A. M. Zubareva D. M. Kolesnikova A. A. Lebedev N. N. Samus’ L. A. Sat 《Astronomy Reports》2014,58(5):319-327
The new stage of work on digitizing the astronomical plates of the Sternberg Astronomical Institute’s collection and searching for new variable stars using the digitized photographic plates includes a considerable improvement of the automated search techniques for objects with variable brightnesses. In particular, the technique for taking into account the non-linear response of the photographic light detector has been improved. Applying the improved techniques to 182 digitized images of a 10° × 10° field centered at SA9, obtained from scanning photographic plates taken with the Sternberg Astronomical Institute 40-cm astrograph, has enabled the discover and study of 77 new variable stars (MDV 519–595). These include 3 Cepheids, 2 probable BY Draconis stars, 65 eclipsing binaries, 3RR Lyrae stars, 1 high-amplitude δ Scuti star (HADS), and 3 irregular variables. Special CCD observations have confirmed the presence of brightness variations in 7 of the 77 variables that were initially considered uncertain. 相似文献
5.
Antipin V. S. Kuzmin M. I. Odgerel D. Kousch L. V. Sheptyakova N. V. 《Doklady Earth Sciences》2019,487(2):917-921
Doklady Earth Sciences - The early Mesozoic Baga-Khentei pluton is a part of the Daurian–Khentei batholite that was formed under the impact of the Mongolian plume on the lower horizons of the... 相似文献
6.
A. M. Zubareva E. P. Pavlenko M. V. Andreev S. V. Antipin N. N. Samus’ A. V. Sergeev 《Astronomy Reports》2011,55(3):224-229
We have obtained data on various brightness states of the polar MT Dra over five years of observations, including the first
multicolor photometry for this close binary. We confirm the known orbital period, which has remained constant over 17 years,
which is unusual for cataclysmic binaries. Our observations in October 2006 demonstrated a transition of the polar to its
low brightness state within one day. 相似文献
7.
The photometric elements of the eclipsing binary NSV 18773 (HD 99898) have been determined for the first time by analyzing its V-and I-band light curves from the ASAS-2 and ASAS-3 catalogs. Based on these elements and using other published spectroscopic and photometric data, we constructed a consistent system of geometrical and physical parameters for the system that consists of two stars (M 1 = 20M ⊙, Sp1=B0V, R 1 = 5.0R ⊙ and M 2 = 14M ⊙, Sp2 = B1V, R 2 = 6.5R ⊙) in elliptical orbits (P = 5 . d 049, e = 0.365, a = 40.1R ⊙). The distance to the system is d = 3.3 kpc, the interstellar extinction is A V = 2 . m 0, and the age is t = 2.8 × 106 yr. NSV 18773 is a visual binary with components V A = 9 . m 9 and V B = 10 . m 3 separated by 0 . " 8. The third light (L 3 = 0.61) that we found by analyzing the light curves shows that the eclipsing binary is the system’s fainter component B. We confirmed the rapid apsidal motion of the star detected by Otero and Wils (2006) and refined its observed period: U obs = 150 ± 6 yr. Our photometric elements and physical parameters allowed the apsidal parameter $\bar k_2^{obs} = 0.0135(14)$ , which reflects the density distribution along the radii of the component stars, to be determined. Within the error limits, the derived parameter agrees with its theoretically expected value, $\bar k_2^{th} = 0.0119(8)$ , from current evolutionary models of stars of the corresponding masses and ages. 相似文献
8.
Antipin S. V. Zubareva A. M. Belinski A. A. Burlak M. A. Ikonnikova N. P. Sokolovsky K. V. 《Astronomy Letters》2020,46(10):677-690
Astronomy Letters - Results of the first multicolor photometric observations of the unusual dwarf nova V2466 Cygni during its 2003 and 2019 superoutbursts are presented. The total amplitude of the... 相似文献
9.
M. I. Kuzmin E. B. Karabanov A. A. Prokopenko V. F. Gelety V. S. Antipin D. F. Williams A. N. Gvozdkov 《International Journal of Earth Sciences》2000,89(2):183-192
With this paper we present a first attempt to combine the direct results on lithology, composition and age dating in the
boreholes BDP-93, BDP-96 and BDP-97 with geological and seismic data from the areas where those sections were drilled. The
sedimentary environments represented by the BDP boreholes are markedly different and possess characteristic lithological features.
The results of the deep drilling provide the essential means for testing numerous age models used in geological reconstructions
of the Lake Baikal rifting dynamics. Neither the basin-wide unconformity interpreted from seismic data, nor the interpreted
change from shallow-water to deep-water facies at the boundary of the seismic stratigraphic complexes were found in the BDP-96
boreholes on Academician Ridge. Also, lithology does not support the proposed reconstructions of intense lake level fluctuations
and transgressions during the Pliocene at Academician Ridge. The continuous deep-water hemipelagic sedimentation at Academician
Ridge has existed for the past 5 Ma. The beginning of an intense rifting phase of the Neobaikalian sub-stage and related drastic
changes in sedimentation processes were interpreted on seismic sections as the basin-wide unconformity B10. Different age
estimates for this boundary ranged from Late Pliocene (3.5 Ma) to Plio-Pleistocene boundary. As shown by BDP-96 borehole,
B10 is associated with a lithological change from diatomaceous ooze to dense silty clay and not with an erosional contact.
The new age for this boundary in BDP-96 is approximately 2.5 Ma. This new age constraint suggests that the upper sedimentary
strata of Northern Baikal (1.5–1.7 km thick) have formed during the past 2.5 Ma with average sedimentation rates of 60–70 cm/ka.
The BDP-93 boreholes at Buguldeika suggest that uplift in Primorsky Range took place prior to 1.07–1.31 Ma, a date which exceeds
the age of previous geological models.
Received: 12 March 1999 / Accepted: 10 February 2000 相似文献
10.