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41.
Grigory I. Dolgikh Mstislav N. Dubrov Stanislav G. Dolgikh Sergei N. Kovalev Vladimir V. Ovcharenko Egor A. Savvin Vladimir A. Chupin Vyacheslav A. Shvets Sergei V. Yakovenko 《Acta Geophysica》2006,54(2):187-197
The paper considers possibilities of applying laser strainmeters for the study of earthquake physics. One of laser strainmeters
is described. A high efficiency of using the laser strainmeters for the study of earthquakes and their precursors is shown.
In records of the spaced laser strainmeters, anomalous deformations propagating from the east to the west with the speed comparable
with that of migration of earthquakes were found. 相似文献
42.
Extensive computer simulations aimed at testing a hypothesis that impact craters may explain the scaling behaviour of surface
spectra are presented. The simulations show that indeed crater effects alone may explain the spectral scaling of Mars’ topography
revealed from MOLA data. The range of the scaling exponents obtained for a wide range of simulation parameters does not exceed
the limits observed for Mars. The simulations suggest that the shape of large craters is the key factor leading to the two
scaling ranges in the surface spectra. Particular values of the scaling exponents may additionally depend on the depth-diameter
relationship and the crater size distribution. 相似文献
43.
Dynamical and kinematic properties of Bianchi-II cosmological models with rotation and expansion are investigated. Exact solutions of Einstein field equations are obtained which describe the evolution of a rotating Universe. Exact solutions of null, timelike and spacelike geodesics are constructed. Two new cosmological tests for rotating universes are discussed: cosmological lens effect and cosmological mirror effect. 相似文献
44.
Vladimir Garrido Ortega Gladys Lopes Vieira J.A. de Freitas Pacheco 《Astrophysics and Space Science》1998,262(3):271-295
On the basis of Jeans equations we study some dynamical properties of a sample of E galaxies considered as oblate and prolate spheroids. Although the results emphasize the anisotropy as the dominant dynamical factor both for oblate and prolate configurations, the sample contains some oblate galaxies apparently isotropic consistent with full rotational support. Comparisons of the mass-to-luminosity ratios obtained from our models with ratios derived from recent evolutionary synthesis models do not seem to leave room for nonluminous matter within the ranges (of the order of one de Vaucouleurs' radius) of the kinematical observations. Such comparisons suggest that a flatter than the classical Salpeter IMF would lead to better agreement with the dynamical results obtained within the framework of our models. 相似文献
45.
Vít Kárník Dana Procházková Zdeňka Schenková Julius Drimmel Dieter Mayer-Rosa Dragutin Cvijanovic Vladimir Kuk Andelka Miloševič Francesco Giorgetti Reviewer J. Janský 《Studia Geophysica et Geodaetica》1978,22(4):411-414
Summary Isoseismal maps of the three strongest Friuli aftershocks of September 1976 were compiled using the contributions from European countries within the shaken area. The characteristic features of the macroseismic fields are discussed. 相似文献
46.
Igor A. Dmitrenko Dorothea Bauch Sergey A. Kirillov Nikolay Koldunov Peter J. Minnett Vladimir V. Ivanov Jens A. Hölemann Leonid A. Timokhov 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(4):513-527
Inflow of Atlantic water (AW) from Fram Strait and the Barents Sea into the Arctic Ocean conditions the intermediate (100–1000 m) waters of the Arctic Ocean Eurasian margins. While over the Siberian margin the Fram Strait AW branch (FSBW) has exhibited continuous dramatic warming beginning in 2004, the tendency of the Barents Sea AW branch (BSBW) has remained poorly known. Here we document the contrary cooling tendency of the BSBW through the analysis of observational data collected from the icebreaker Kapitan Dranitsyn over the continental slope of the Eurasian Basin in 2005 and 2006. The CTD data from the R.V. Polarstern cruise in 1995 were used as a reference point for evaluating external atmospheric and sea-ice forcing and oxygen isotope analysis. Our data show that in 2006 the BSBW core was saltier (by ~0.037), cooler (by ~0.41 °C), denser (by ~0.04 kg/m3), deeper (by 150–200 m), and relatively better ventilated (by 7–8 μmol/kg of dissolved oxygen, or by 1.1–1.7% of saturation) compared with 2005. We hypothesize that the shift of the meridional wind from off-shore to on-shore direction during the BSBW translation through the Barents and northern Kara seas results in longer surface residence time for the BSBW sampled in 2006 compared with samples from 2005. The cooler, more saline, and better-ventilated BSBW sampled in 2006 may result from longer upstream translation through the Barents and northern Kara seas where the BSBW was modified by sea-ice formation and interaction with atmosphere. The data for stable oxygen isotopes from 1995 and 2006 reveals amplified brine modification of the BSBW core sampled downstream in 2006, which supports the assumption of an increased upstream residence time as indicated by wind patterns and dissolved oxygen values. 相似文献
47.
Hypothesis of possible superconductivity of the iced matter of the rings of Saturn (based on the data of Voyager and Pioneer
space missions) allow us to explain many phenomena which have not been adequately understood earlier. Introducing into planetary
physics force of magnetic levitation of the superconducting iced particle of the rings, which interact with magnetosphere
of the planet, becomes to be possible to explain origin, evolution, and dynamics of the rings; to show how the consequent
precipitation of the rings’ matter upon the planet was concluded; how the rings began their rotation; how they were compressed
by the magnetic field into the thin disc, and how this disc was fractured into hundreds of thousands of separated rings; why
in the ring B do exist “spokes”; why magnetic field lines have distortion near by ring F; why there is a variable azimuth brightness of the ring A; why the rings reflected radio waves so efficiently; why exists strong electromagnetic radiation of the rings in the 20.4
kHz–40.2 MHz range and Saturnian kilometric radiation; why there is anomalous reflection of circularly polarized microwaves;
why there are spectral anomalies of the thermal radiation of the rings; why the matter of the various rings does not mix but
preserves its small-scale color differences; why there is an atmosphere of unknown origin nearby the rings of Saturn; why
there are waves of density and bending waves within Saturn’s rings; why planetary rings in the solar system appear only after
the Belt of Asteroids (and may be the Belt of Asteroids itself is a ring for the Sun); why our planet Earth has no rings of
its own. 相似文献
48.
The Earth's crust faults and lineaments group in clusters with predominant N-S and E-W (System I) and NW-SE and NE-SW (System II) directions. The earthquake epicenters of the Benioff seismofocal zones follow the same regularities. In other words, seismofocal zones (epicenters of earthquakes) constitute a part of the regular network of the Earth's crust and lithosphere faults and lineaments. Mathematical modeling of stress distribution in the lithosphere due to a change of the Earth's ellipsoid compression showed that the principal stresses σ1 and σ2 are oriented in N-S and E-W directions, while corresponding shear stresses τ are oriented in NE-SW and NW-SE directions. It is shown that the secular deceleration of the Earth's rotation can be a reasonable mechanism for the change of Earth's ellipsoid compression and, consequently, for the origin of the regular system of faults and lineaments described above. 相似文献
49.
Valentina G. Klochkova Eugene L. Chentsov Tonu Kipper Vladimir E. Panchuk Nonna S. Tavolganskaya Maxim V. Yushkin 《Astrophysics and Space Science》2011,335(1):83-89
We present a spectral atlas of 4 B and A stars containing spectra in a poorly studied spectral range of 305–452 nm. The atlas
is based on high resolution (R=60 000) spectra obtained with the 6 meter telescope (SAO, Russia) combined with the NES-spectrograph. The procedure of spectral
lines identification and compilation of the atlas is discussed in detail. Using the spectral data we thoroughly investigated
the velocity field in expanding atmospheres and envelopes of hot evolved stars β Ori, α Cyg and supergiant KS Per with the extreme hydrogen deficiency. The complete atlas and list of the identified spectral lines
will be available via the astronomical database SIMBAD. 相似文献
50.
A set of smoothed temperature gradient profiles around overshooting layers at the solar convective zone bottom is considered. In classical local theories of convection the one point defined according to the Schwarzschild criterion is enough to describe a convective boundary. To get a sophisticated picture of the overshooting we use four points to compute the transition overshooting functions. Analyzing the transition gradient profiles we found that the overshooting convective flux may be either positive or negative. A negative overshooting flux appears in nonlocal convective theories and causes a steep temperature gradient profile. But we propose an evenly smoothed gradient which corresponds to a convective flux positive everywhere. To outline the effect of the temperature gradient on the solar oscillations the squared Brunt–Väisälä frequency N 2 is calculated. In local convective theories the N 2 profile shows the discontinuity of the first derivative at the convective boundary, while all smoothed profiles eliminate the break. 相似文献