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721.
722.
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724.
The history of the discovery of hot gas in galaxies is briefly reviewed, and the main properties of this gas described, emphasizing the need to refine these properties, in particular, the mass of the gas. It is proposed to do this via observations of the Sunyaev-Zel’dovich (SZ) effect due to hot gas in the coronas of elliptical galaxies. The absolute and relative perturbations of the spectrum of the cosmic microwave background (CMB) radiation due to scattering of the CMB photons by electrons with a Maxwellian energy distribution are calculated. The possibility of observing the SZ effect is demonstrated using three elliptical galaxies as examples. The kinematic SZ effect arising due to the peculiar motions and rotations of the galaxies is also accessible to observations. Together with X-ray data, such observations would enable refinement of the properties of gas in galaxies, and also yield additional information about the rotation of galaxies, possible accretion flows in the galactic gas, and hot galactic winds. 相似文献
725.
I. V. Pekov N. V. Chukanov N. N. Kononkova N. V. Zubkova M. Kh. Rabadanov D. Yu. Pushcharovsky 《Geology of Ore Deposits》2008,50(8):749-754
Elpasolite, K2NaAlF6, has been found for the first time in a pegmatite related to peralkaline foid syenite at Mt. Koashva, Khibiny alkaline pluton, Kola Peninsula, Russia, as pale pink octahedral crystals up to 2 mm in size within cavities in the natrolite core of pegmatite in association with amicite, sodalite, aegirine, pectolite, catapleiite, sitinakite, lemmleinite-K, and vinogradovite. The chemical composition determined with an electron microprobe is as follows, wt %: 31.53 K; 9.22 Na; 11.20 Al; 47.21 F; total is 99.16. The empirical formula is K1.96Na0.98Al1.01F6.05. The infrared spectrum is given. The crystal structure has been refined to R = 0.030, space group Fm $ \bar 3 Elpasolite, K2NaAlF6, has been found for the first time in a pegmatite related to peralkaline foid syenite at Mt. Koashva, Khibiny alkaline pluton,
Kola Peninsula, Russia, as pale pink octahedral crystals up to 2 mm in size within cavities in the natrolite core of pegmatite
in association with amicite, sodalite, aegirine, pectolite, catapleiite, sitinakite, lemmleinite-K, and vinogradovite. The
chemical composition determined with an electron microprobe is as follows, wt %: 31.53 K; 9.22 Na; 11.20 Al; 47.21 F; total
is 99.16. The empirical formula is K1.96Na0.98Al1.01F6.05. The infrared spectrum is given. The crystal structure has been refined to R = 0.030, space group Fm
m, a = 8.092 ?. The result of a special X-ray powder diffraction study confirmed the suggestion made by Morss (1974) that reflections
violating space group Fm
m in some published X-ray powder patterns of natural elpasolite are Kβ-lines.
Original Russian Text ? I.V. Pekov, N.V. Chukanov, N.N. Kononkova, N.V. Zubkova, M.Kh. Rabadanov, D.Yu. Pushcharovsky, 2007,
published in Zapiski Rossiiskogo Mineralogicheskogo Obshchestva, 2007, No. 6, pp. 76–84. 相似文献
726.
V.B. Vasilenko A.V. Tolstov V.A. Minin L.G. Kuznetsova N.V. Surkov 《Russian Geology and Geophysics》2008,49(12):894-907
The intensity of postmagmatic processes in the Botuobinskaya pipe kimberlites was estimated from the calculated content of normative secondary quartz (Q). Several simple algorithms are proposed to calculate the Q content from chemical analyses of kimberlites. Ten groups of altered kimberlites have been recognized from the Q contents. The contents of MgO, some trace elements, and LREE in the groups, the contents of Cr and Ca of crimson garnets, the diamond contents of kimberlites, and the average weight of diamonds decrease as the Q content increases. It is shown that the negative SiO2–MgO correlation is the most effective indicator of the postmagmatic alteration of kimberlites. As the degree of their secondary alteration increases, the kimberlites transform into an assemblage of quartz and clay minerals enriched in some trace elements and almost completely lacking REE and diamonds. 相似文献
727.
B.P. Chernyago A.I. Nepomnyashchikh G.I. Kalinovskii 《Russian Geology and Geophysics》2008,49(12):971-977
Relations between indoor and soil gas radon were experimentally studied in villages of the Baikal region. On the basis of the obtained data, the soil-to-indoor radon ratio was calculated, which can be used for prediction of radon pollution in buildings of the same kind. 相似文献
728.
V.B. Bazarova L.M. Mokhova M.A. Klimin L.A. Orlova K.Yu. Bazarov 《Russian Geology and Geophysics》2008,49(12):978-985
Climatic changes in southeastern Transbaikalia in the Middle and Late Holocene and their influence on alluvial sedimentation environments are reconstructed from the results of study of the Ilya floodplain sediments (Alkhanai National Park). At the beginning of the Subboreal period, the regional climate became more arid, which led to a significant increase in steppe species communities in the landscapes. Intense climate aridization also took place at the beginning and at the end of the Subatlantic period of the Holocene. The alluvial-sedimentation rate increased during the weakening of aridization and decreased during cooling and the intensification of aridization. The obtained regional data are compared with data on the adjacent areas and the global climatic changes in the Northern Hemisphere. 相似文献
729.
The methods of celestial mechanics can be used to construct a mathematical model for the perturbed rotational motions of the deformable Earth that can adequately describe the astrometric measurements of the International Earth Rotation Service (IERS). This model describes the gravitational and tidal influences of the Sun and Moon. Fine resonant interactions of long-period zonal tides (annual, semiannual, monthly, and biweekly) with the diurnal and semidiurnal tides are revealed. These interactions can be reliably confirmed via a spectral analysis of the IERS data. Numerical modeling of tidal irregularities of the Earth’s axial rotation was carried out, focusing on the analysis and forecasting of variations of the day length occurring within short time intervals of a year or shorter (intrayear variations). 相似文献
730.
We developed light requirements for eelgrass in the Pacific Northwest, USA, to evaluate the effects of short- and long-term
reductions in irradiance reaching eelgrass, especially related to turbidity and overwater structures. Photosynthesis-irradiance
experiments and depth distribution field studies indicated that eelgrass productivity was maximum at a photosynthetic photon
flux density (PPFD) of about 350–550 μmol quanta m−2 s−1. Winter plants had approximately threefold greater net apparent primary productivity rate at the same irradiance as summer
plants. Growth studies using artificial shading as well as field monitoring of light and eelgrass growth indicated that long-term
survival required at least 3 mol quanta m−2 day−1 on average during spring and summer (i.e., May-September), and that growth was saturated above about 7 mol quanta m−2 day−1. We conclude that non-light-limited growth of eelgrass in the Pacific Northwest requires an average of at least 7 mol quanta
m−2 day−1 during spring and summer and that long-term survival requires a minimum average of 3 mol quanta m−2 day−1. 相似文献