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31.
32.
N. L. Ivanova 《Astrophysics》1994,37(2):135-137
Results are presented from a spectrophotometric study of SU Aurigae in the continuum and on spectral lines.Translated from Astrofizika, Vol. 37, No. 2, pp. 229–233, April–June, 1994. 相似文献
33.
Glukhov A. N. Kotov A. B. Priymenko V. V. Sal’nikova E. B. Ivanova A. A. Plotkina Yu. V. Fedoseenko A. M. 《Geotectonics》2022,56(2):178-190
Geotectonics - In our study we analyzed the composition of granitoid rocks within the Kongo magmatic zone of the Omolon median mass. The studied calc-alkaline granitoids cut through the Early... 相似文献
34.
M. V. Charykova V. G. Krivovichev N. M. Ivanova V. V. Semenova 《Geology of Ore Deposits》2015,57(8):691-698
The aim of this study is the synthesis of CuSeO3·2H2O (chalcomenite analog), ZnSeO3·2H2O, and ZnSeO3·H2O and the investigation of their solubility in water. CuSeO3·2H2O has been synthesized from solutions of Cu nitrate and Na selenite, while Zn selenites were synthesized from solutions of Zn nitrate and Na selenite. The samples obtained have been examined with X-ray diffraction and infrared and Raman spectroscopy. The solubility has been determined using the isothermal saturation method in ampoules at 25°C. The solubility has been calculated using the Geochemist’s Workbench (GMB 9.0) software package. Solubility products have been calculated for CuSeO3·2H2O (10–10.63), ZnSeO3·2H2O (10–8.35), and ZnSeO3·H2O (10–7.96). The database used comprises thermodynamic characteristics of 46 elements, 47 base particles, 48 redox pairs, 551 particles in solution, and 624 solid phases. The Eh–pH diagrams of the Zn–Se–H2O and Cu–Se–H2O systems were plotted for the average contents of these elements in underground water in oxidation zones of sulfide deposits. 相似文献
35.
Low phase angle effects in photometry of trans-neptunian objects: 20000 Varuna and 19308 (1996 TO66)
We present the results of photometric observations of trans-neptunian object 20000 Varuna, which were obtained during 7 nights in November 2004-February 2005. The analysis of new and available photometric observations of Varuna reveals a pronounced opposition surge at phase angles less than 0.1 deg with amplitude of 0.2 mag relatively to the extrapolation of the linear part of magnitude-phase dependence to zero phase angle. The opposition surge of Varuna is markedly different from that of dark asteroids while quite typical for moderate albedo Solar System bodies. We find an indication of variations of the scattering properties over Varuna's surface that could result in an increase of the lightcurve amplitude toward zero phase angle. It is shown that a similar phase effect can be responsible for lightcurve changes found for TNO 19308 (1996 TO66) in 1997-1999. 相似文献
36.
summary . The magnetic observatories at Vysokaya Dubrava and at Arti in Sverdlovsk region have operated in parallel since 1972 January. In spite of the rather small distance between them (160 km), it has been established that during that time, there have been differences in the geomagnetic field variations over a wide range of frequencies. The secular variation also differs appreciably. Over a period of four years the difference in the horizontal component between the observatories increased by 3 nT, the difference in the vertical component by 4 nT and the difference in the total intensity by 6 nT, while the difference in declination decreased by 0.6 min. Besides the normal geomagnetic secular variation, governed by processes in the Earth's core, secular-variation anomalies (SVA) linked with processes in the lithosphere may also take place. The intensity of the local SVAs reaches 10–2 nT/yr, whilst their size does not exceed 15 km. It is undesirable to locate an observatory in a region where an SVA exists since this will distort the normal secular-Variation pattern. It is therefore important to know to what extent observations at the observatory reflect the mean value of the secular variation for that area. For this purpose we would recommend performing a highly accurate survey, for example the total intensity in a network of radial lines in a region around the observatory of radius 50–100 km. Such investigations have been performed around the Arti observatory with an accuracy of the repeated measurements of ±0.3 nT in 1974 and ±0.2 nT in 1975. Ten local SVAs with intensities from 2–14 nT/yr were revealed around the observatory. The observatory of Arti is situated in a quiet region. 相似文献
37.
O.A. Troshichev V.A. Gizler I.A. Ivanova A.Yu. Merkuryeva 《Planetary and Space Science》1979,27(12):1451-1459
The distant effects of the field-aligned currents (FAC) observed by TRIAD are computed for conditions of low and moderate activity. The systems of total ionospheric currents (both Hall and Pedersen) generated by corresponding FAC are also examined and the contribution of the distant effects and the ionospheric currents into the total equivalent current system is estimated. The conclusions are as follows. In cases of low magnetic activity the magnetic effects produced by Pedersen currents are mainly cancelled by the FAC distant effect in accord with Fukushima's theorem. In cases of moderate activity when the zone of high ionospheric conductivity and the two-sheet FAC structure are present the FAC distant effect is too small to cancel the effect of Pedersen currents. For these conditions the system of total ionospheric currents shows the best correspondence with the experimental equivalent current system. Effects produced by the IMF azimuthal component are also analysed. 相似文献
38.
Abstract— Dengli is a highly weathered 243.5-g chondrite that was found in 1976 in the Karakoom desert, Turkmenia. The meteorite contains olivine, high-Ca and low-Ca twinned pyroxenes, plagioclase, merrillite, cryptocrystalline material, and opaque minerals: metallic Fe, Ni, troilite, chromite. Based on the texture and the compositions of olivine (Fa19.6, n = 52, C.V. = 19.3) and low-Ca pyroxene (Fs18.2, n = 27, C.V. = 17.0), Dengli is classified as an H3.8 breccia. 相似文献
39.
40.
A. V. Ivanova V. L. Afanasiev P. P. Korsun A. R. Baranskii M. V. Andreev V. A. Ponomarenko 《Solar System Research》2012,46(4):313-319
The results of the photometric observations of comet 29P/Schwassmann-Wachmann 1 are analyzed. The comet demonstrates substantial activity at heliocentric distances larger than 5 AU, i.e., outside the water ice sublimation zone. The CCD images of the comet were obtained in wideband R filters at the 6-meter telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) and at the 2-meter Zeiss-2000 telescope of the Peak Terskol Observatory. The processing of the images with special digital filters allowed the active structures (jets) to be distinguished in the dust coma of the comet. With the cross-correlation method, the rotation period of the cometary nucleus was determined as 12.1 ± 1.2 and 11.7 ± 1.5 days for the observations taken in December 2008, and February 2009, respectively. The probable causes of the difference in the estimates of the rotation period of the cometary nucleus obtained by different authors are discussed. 相似文献