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31.
Results of magnetic observations in Yuzhno-Sakhalinsk during a strong earthquake and a local swarm of earthquakes, as well as magnetic signals recorded during propagation of seismic waves, are considered. The possibility of the identification of these signals in magnetograms is discussed. The results of this study are shown to be significant for the development of a prompt method for warning of the arrival of seismic waves.  相似文献   
32.
Nanocrystals were detected and identified in rocks by the method of Raman spectroscopy. The experiments showed that the Raman scattering spectra of fine-lamellar arkosic sandstone exhibit bands corresponding to lattice vibrations of anatase, α-quartz, and plagioclase. In all spectra of the rock, the bands are displaced towards high frequencies as compared with their position in spectra of single crystals and widen on the same side. These results show that, in all of the studied places of the sample, the particles of anatase, quartz, and plagioclase have nanometer sizes, namely, of the order of 10 nm in anatase and quartz and about 20 nm in plagioclase. Moreover, in different places of the sample, not only the shape and position of the bands under study but also their intensity vary, the latter being directly proportional to the concentration of nanocrystals.  相似文献   
33.
A method was developed to obtain from a signal station the spatial and temporal distribution ofV p /V s ratios before earthquakes of magnitude>6. It was shown thatV p /V s values strongly depend upon the relative positions of the stations, the future large earthquake and the foci of the smaller earthquakes used forV p /V s determination. The appearance of a zone of anomalousV p /V s values with linear dimensions of the order of 100 km was noted at least 4 years before a deep earthquake of magnitude 7. Similar size anomalous zones were detected one year before some magnitude 6 earthquakes. V p /V s values decreased by a small but distinct amount during this time. Additionally, local short term minima inV p /V s ratios were observed some months before the major event. The epicenters of the large earthquakes were located within the 100 km size zone where the gradients of theV p /V s field were largest.  相似文献   
34.
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   
35.
Leningrad State University. Translated from Astrofizika, Vol. 32, No. 2, pp. 277–289, March–April, 1990.  相似文献   
36.
According to observations in the Crimea and in Zvenigorod the continuum in the night airglow from 8000 to 11,000 Å has values of about 1–2 RA? and does not rise markedly with the increase in the wavelength.  相似文献   
37.
We presented a phenomenological mode that attributes the precession of perihelion of planets to the relativistic correction. This modifies Newton’s equation by adding an inversely cube term with distance. The total energy of the new system is found to be the same as the Newtonian one. Moreover, we have deduced the deflection of light formula from Rutherford scattering. The relativistic term can be accounted for quantum correction of the gravitational potential and/or self energy of objects.  相似文献   
38.
The search of roAp stars at Mt. Dushak-Erekdag Observatory was started in 1992 using the 0.8 m Odessa telescope equipped with a two-star high-speed photometer. We have observed more than a dozen stars so far and discovered HD 99563 as roAp star while BD+8087 is suspected to have rapid oscillations. Negative results of our observations for the search of rapid oscillations in four stars in NGC 752 are also discussed.  相似文献   
39.
Ladeyschikov  D. A.  Sobolev  A. M. 《Astronomy Reports》2022,66(11):1082-1097
Astronomy Reports - The paper deals with the issues of cross-identification of sources from various astronomical catalogs. One of the main problems under consideration is how to cross-identify a...  相似文献   
40.
Sytov  A. Yu.  Sobolev  A. V. 《Astronomy Reports》2022,66(11):936-952
Astronomy Reports - The paper describes three methods for constructing synthetic Doppler tomograms. These methods are applied to the results of MHD simulation of the V808 Aur polar, and the...  相似文献   
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