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51.
Malakhova T. V. Kanapatskiy T. A. Sidorov I. G. Rusanov I. I. Malakhova L. V. Proskurnin V. Yu. Pimenov N. V. 《Oceanology》2018,58(6):909-917
Oceanology - A seasonal study of microbial methane oxidation (MO) and sulfate reduction (SR) processes in bottom sediments was carried out at five stations in the estuarian Sevastopol coastal area,... 相似文献
52.
Numerical simulation of atmospheric disturbances during the first hours after the Chelyabinsk and Tunguska space body impacts has been carried out. The results of detailed calculations, including the stages of destruction, evaporation and deceleration of the cosmic body, the generation of atmospheric disturbances and their propagation over distances of thousands of kilometers, have been compared with the results of spherical explosions with energy equal to the kinetic energy of meteoroids. It has been shown that in the case of the Chelyabinsk meteorite, an explosive analogy provides acceptable dimensions of the perturbed region and the perturbation amplitude. With a more powerful Tunguska fall, the resulting atmospheric flow is very different from the explosive one; an atmospheric plume emerges that releases matter from the meteoric trace to an altitude of the order of a thousand kilometers. 相似文献
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Oceanology - The bearded seal occurs in virtually all Arctic seas. During the spring (pupping and mating season), this species is characterized by high underwater acoustic activity; studies... 相似文献
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This paper summarizes the observations of microseismic emissions by these authors in several areas of the Russian part of the Fennoscandian Shield to assess the potential of microseismicity to determine the present-day activity of local features in the upper part of the geologic medium. We give amplitude–frequency characteristics and the space–time distribution of naturally occurring microseismic events that are hypothesized to be of endogenous origin. We discuss the relationships these characteristics have to the regional geodynamic setting, average dimensions, and petrographic composition of active rock blocks. 相似文献
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Sukhanova I. N. Flint M. V. Sakharova E. G. Fedorov A. V. Makkaveev P. N. Nedospasov A. A. 《Oceanology》2018,58(6):802-816
Oceanology - Based on the material obtained in the spring–summer season of 2016, the composition and quantitative distribution of phytoplankton in the Ob estuary and over the Kara Sea shelf... 相似文献
59.
This work demonstrates the possibility of magnetic-field topology investigations using microwave polarimetric observations. We study a solar flare of GOES M1.7 class that occurred on 11 February, 2014. This flare revealed a clear signature of spatial inversion of the radio-emission polarization sign. We show that the observed polarization pattern can be explained by nonthermal gyrosynchrotron emission from the twisted magnetic structure. Using observations of the Reuven Ramaty High Energy Solar Spectroscopic Imager, Nobeyama Radio Observatory, Radio Solar Telescope Network, and Solar Dynamics Observatory, we have determined the parameters of nonthermal electrons and thermal plasma and identified the magnetic structure where the flare energy release occurred. To reconstruct the coronal magnetic field, we use nonlinear force-free field (NLFFF) and potential magnetic-field approaches. Radio emission of nonthermal electrons is simulated by the GX Simulator code using the extrapolated magnetic field and the parameters of nonthermal electrons and thermal plasma inferred from the observations; the model radio maps and spectra are compared with observations. We have found that the potential-magnetic-field approach fails to explain the observed circular polarization pattern; on the other hand, the Stokes-\(V\) map is successfully explained by assuming nonthermal electrons to be distributed along the twisted magnetic structure determined by the NLFFF extrapolation approach. Thus, we show that the radio-polarization maps can be used for diagnosing the topology of the flare magnetic structures where nonthermal electrons are injected. 相似文献
60.