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The angular anisotropy of cosmic radio emission at frequencies of 260, 512, 772, and 1028 kHz was studied on the WIND spacecraft when it moved to a distance of ~1.5×106 km from the Earth at the deepest phase of the last solar minimum. The modulation index of the temperature of the spacecraft dipole antenna rotating in the plane of the ecliptic was found to have an indistinct frequency dependence with a maximum of 17% near 500 kHz. This result modifies significantly the conclusions of the only similar experiment on the IMP-6 spacecraft carried out under less favorable observing conditions. Existing ideas about the causes of the radio-background anisotropy in the opacity region of the Galactic gas disk are briefly reviewed. 相似文献
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D. K. Kalmykov A. I. Ponimaskin A. F. Gimaltdinova M. Yu. Tokarev 《Moscow University Geology Bulletin》2010,65(5):306-315
Several petrophysical models were constructed in order to evaluate the potential efficiency of AVO analysis based on the example
of the Priobskoe Oilfield. Synthetic seismograms of different signal-to-noise ratios were calculated. AVO characteristics,
such as the intercept and gradient, were obtained based on the evidence from these seismograms. The conditions under which
AVO analysis could be used in further investigations were determined. 相似文献
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Water Resources - The Crimean Peninsula, with 84% of its territory composed of soluble rocks, is a region of wide occurrence and diverse manifestations of karst. Practically all groundwater of... 相似文献
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V. A. Luchinina I. V. Korovnikov N. V. Novozhilova D. A. Tokarev 《Stratigraphy and Geological Correlation》2013,21(2):131-149
The Early Cambrian history of the development of the Siberian Platform was marked by events of global significance. In the Early Cambrian the Siberian Platform was the centre of appearance of the first shelly fossils. For this reason, paleobiogeographical features of the distribution of fossils are of interest for scientists as a tool for paleogeographic and paleogeodynamic reconstructions. An analysis of changes in the Early Cambrian biota taxonomic diversity allowed us to reveal two major stages in its development: (1) Late Vendian (Tommotian and Atdabanian Stages): spreading of the Siberian biota worldwide; (2) Late Botomian-Toyonian Stages: an increase in the degree of endemism, extinction of archeocyaths, reduction in organogenic structures, deposition of black shales, and flourishing of trilobites. A permanent increase in the degree of biota endemism, which reached its maximum in the Botomian Stage, and the first appearance of migrants at the generic and species level at the same time, coincided with the first major transgressive phases. The study of the geographic distribution of diverse groups of the Early Cambrian fauna and calcareous algae of the Siberian basin allowed us to identify a number of biofacies of different age, whose boundaries do not coincide. The evolution and change in the taxonomic composition of the Siberian basin biota were affected by events of the first (Salair) phase of the Caledonian orogeny, manifested in the Altai-Sayan region much earlier than in other parts of the world and influencing the geological history of the Siberian Platform. These events resulted in the extinction and appearance of some specific groups of the Tommotian fauna in the Siberian Platform. 相似文献
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A.E. Kontorovich V.A. Kontorovich I.V. Korovnikov S.V. Saraev N.V. Sennikov Yu.F. Filippov A.I. Varlamov A.S. Efimov Yu.A. Filiptsov A.A. Postnikov A.A. Terleev G.A. Karlova K.E. Nagovitsin D.A. Tokarev T.P. Baturina I.A. Gubin B.B. Kochnev N.V. Novozhilova V.A. Luchinina 《Russian Geology and Geophysics》2012,53(10):972-981
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Water Resources - The δ2H and δ18O values of the atmospheric precipitations in the Khibins vary within the range –147 ≤ δ2H ≤ –37‰, –20 ≤... 相似文献
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Solar wind observations by means of bi-static decametric radar SURA-WIND allow studying a fine structure of solar wind plasma
irregularities with resolution up to 40 km. Spectral analysis and Hurst exponents method were applied to analyze the scintillation
of radio signal transmitted through turbulent layers of Ionosphere and Solar wind plasma.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Water Resources - External water exchange of bays of the lakes Onega (Kondopoga and Petrozavodsk bays) and Ladoga (Hiidenselkä Bay), considering the exchange with the lake water, was assessed... 相似文献
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The capabilities and restrictions of multi-channel acoustic profiling applied to engineering problems over shallow water basins are discussed. The relationships and graphs for determining the optimal parameters of observation systems, source parameters, and recording systems were obtained based on theoretical studies and model calculations of synthetic seismograms. The efficiency of multi-channel systems for suppressing the majority of noises and determining the velocity characteristics of the section is shown on the basis of examples of model calculations and field measurements. At the same time, the capabilities of a multi-channel system for suppressing multiple waves in shallow-water regions appear to be insufficient. 相似文献