366 research outputs found
On the possible injection of charged particles into the zone of trapped radiation during the main phase of a magnetic storm
Possible injection of charged particles into zone of trapped radiation during main phase of magnetic stor
The geologic mapping of Venus using C-1 format: Sheets 75N254, 60N263
The results of geologic mapping of Venus, produced on the base of Magellan images, are presented. We submit two C-1 format geologic maps with the appropriate legend. The mapping territory was taken from Venera 15 and 16 missions and geologic maps were composed. Magellan images allow us to divide some types of the plains units to determine the lava flow direction and to map with better accuracy
Different types of small volcanos on Venus
One of the studies of volcanic activity on Venus is the comparison of that with the analogous volcanic activity on Earth. The preliminary report of such a comparison and description of a small cluster of small venusian volcanos is represented in detail in this paper
On effect of precession-induced flows in the liquid core for early Earth's history
International audienceSecondary and tertiary flow patterns seen in experiments simulating flow in the Earth's liquid core induced by luni-solar precession of the solid mantle (Vanyo et al., 1995) hint at the development of non-axisymmetric columnar periodic structures. A simple interpretation of the structure formation is presented in a hydrodynamic approach. It is suggested that if similar flow patterns can occur in the Earth's liquid core enclosed into precessing and rotating mantle then kinematic of the flows may be regarded as a possible geodynamo mechanism for early Earth's history (before the solid core formation)
The osteotomy of the knee deformation after gonarthrosis (arthrosis of the knee)
The role of osteotomy of the tibia bone is to remove the bone syndrome and remove they
deformity which was rubbing directly against each other and scratching cartilage
A model of mid-latitude E-region plasma convergence inside a planetary wave cyclonic vortex
International audienceRecently, Shalimov et al. (1999) proposed a new mechanism for large-scale accumulation of long-lived metallic ions in the mid-latitude ionosphere driven by planetary waves in the lower thermosphere. In this mechanism, the combined action of frictional and horizontal magnetic field forces at E-region altitudes causes the plasma to converge and accumulate in large areas of positive neutral wind vorticity within a propagating planetary wave. The present paper provides a theoretical formulation for this mechanism by modelling both horizontal and vertical plasma transport effects within a planetary wave vortex, of cyclonic neutral wind. Non-steady-state numerical solutions of the ion continuity equation show that the proposed accumulation process can enhance the ionization significantly inside the planetary wave vortex but its efficiency depends strongly on altitude, whereas on the other hand, it can be complicated by vertical plasma motions. The latter, which are driven by the same planetary wave wind field under the action of the vertical Lorentz force and meridional wind forcing along the magnetic field lines, can lead to either plasma compressions or depletions, depending on the prevailing wind direction. We conclude that, for shorter times, vertical plasma transport may act constructively to the horizontal gathering process to produce considerable E-region plasma accumulation over large sectors of a planetary wave vortex of cyclonic winds
Energy efficiency by thermal spraying
Machines used by the basic industries of Russia (metallurgy, oil-gas processing and power engineering) are characterized by high metal consumption, which in turn lead to high energy consumption. Their service lives increase and their worn parts are restored by means of low-cost materials for restoration. The processes of Thermal Spraying (TS) are more effective than alternative methods in restoration and increase in service life. Such methods include electroplating, chemical and thermal processing. The results of research and experience have proven this. At the same time, the load on the environment is reduced in comparison with the alternatives by decreasing emissions. Based on OEM publications and our own experience, we analysed the efficiency of TS processes. Plasma spraying was excluded from consideration since it has no real alternative for refractory oxide coatings which are mainly used for gas turbines and jet engines. By the criteria of the coating's quality, performance and cost arc of spraying, flame spraying, HVOF/HVAF, cold spraying and detonation spraying were compared. Commonly used materials for TS, such as metals and carbides in metal bond (cermet), were examined as sprayed materials. This paper shows that a combination of activated arc spraying and HVAF for producing wear and corrosion-resistant coating is a rational variant with respect to a wide variety of parts for the aforementioned industries. Examples of resource-saving in metallurgy, oil-gas processing and power engineering are shown based on our own TS experience in material, equipment and technology development. © 2014 WIT Press.International Journal of Safety and Security Engineering;International Journal of Sustainable Development and Planning;WIT Transactions on Ecology and the Environmen
MnSi nanoparticles embedded in Si: Superparamagnetism with a collective behavior
The doping of Mn in Si is attracting research attentions due to the
possibility to fabricate Si-based diluted magnetic semiconductors. However, the
low solubility of Mn in Si favors the precipitation of Mn ions even at
non-equilibrium growth conditions. MnSi nanoparticles are the common
precipitates, which show exotic magnetic properties in comparison with the
MnSi bulk phase. In this paper we present the static and dynamic
magnetic properties of MnSi nanoparticles. Using the Preisach model, we
derive the magnetic parameters, such as the magnetization of individual
particles, the distribution of coercive fields and the inter-particle
interaction field. Time-dependent magnetization measurements reveal a
spin-glass behavior of the system.Comment: 11 pages, 6 figures, submitted to PR
Dispersive changes in magnetic background noise polarization at 0.1 to 6Hz during sunset and sunrise at L=1.3
Polarization properties of the magnetic background noise (MBN) and the spectral resonance structure (SRS) of the ionospheric Alfv&#233;n resonator (IAR) below the first Schumann resonance but above 0.1&nbsp;Hz are measured by a sensitive pulsation magnetometer at the island of Crete (<i>L</i>=1.3) and analyzed using the existing SRS theory by Belyaev et al.&nbsp;(1989b). The focus of the paper is on the systematic changes in the MBN and SRS properties associated with the transition from a sunlit to a dark ionosphere (sunset) and vice versa (sunrise). We are able to pinpoint in observations an E-region and F-region terminator effect and to simulate it by means of a simple ionosphere model, implying the formalism given by Belyaev et al.&nbsp;(1989b). The E-region terminator effect is associated with an apparent control for the SRS presence or absence with no clear frequency dispersion in polarization properties, whereas the F-region terminator effect exhibits strong frequency dispersion, especially in the low frequency range. This yields a change in the ellipticity of MBN, starting as early as 2 to 3h ahead of the "zero-line" of the terminator. In a 24h presentation of the ellipticity versus frequency and time, the sunrise/sunset effect produces a sharp, dispersive boundary between night and day (day and night). Only inside this boundary, during the night hours, is SRS observed, at times accompanied by a large quasi-periodic long period modulation in the azimuthal angle of the major axis of the polarization ellipse. Attention is also paid to peculiarities in the low frequency range (~0.1Hz), where especially large changes in the polarization properties occur in association with the passage of the terminator. The F-region effect is very distinct and well reproduced by our simple model. Changes in the azimuth associated with the E-region terminator effect are of the order of 20&deg
Vladislav N. Boronenkov — scientist, educator, intellectual
Are given the basic landmarks of the biography of professor, doctor of technical sciences V. N. Boronenkov.Приведены основные вехи биографии профессора, доктора технических наук В. Н. Бороненкова
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