We present the results of our studies of the aperiodic optical flux variability for SS Cyg, an accreting binary systemwith a white dwarf. The main set of observational data presented here was ...obtained with the ANDOR/iXon DU-888 photometer mounted on the RTT-150 telescope, which allowed a record (for CCD photometers) time resolution up to 8 ms to be achieved. The power spectra of the source’s flux variability have revealed that the aperiodic variability contains information about the inner boundary of the optically thick flow in the binary system. We show that the inner boundary of the optically thick accretion disk comes close to the white dwarf surface at the maximum of the source’s bolometric light curve, i.e., at the peak of the instantaneous accretion rate onto the white dwarf, while the optically thick accretion disk is truncated at distances 8.5 × 10
9
cm ∼10
R
WD
in the low state. We suggest that the location of the inner boundary of the accretion disk in the binary can be traced by studying the parameters of the power spectra for accreting white dwarfs. In particular, this allows the mass of the accreting object to be estimated.
Manganese-doped anatase with a nanosized morphology (as spherically shaped nanoparticles) has been synthesized under hydrothermal conditions. It has been shown that manganese is incorporated into the ...titanium dioxide structure to form substitutional solid solutions. At high dopant concentrations, part of the introduced manganese goes to the formation of α-MnO
2
. A significant increase in the optical activity in the visible range and a decrease in the bandgap width down to ~2.4 eV are observed for manganese-doped anatase because of the appearance of extrinsic (multivalent Mn ions) and intrinsic compensating (oxygen vacancies) defects. It has been found that manganese-doped samples are diluted magnetic semiconductors, and the magnetic characteristics increase with increasing manganese content. All manganese-containing samples demonstrate photocatalytic activity in the degradation reaction of indigo carmine when irradiated with visible light. The degree of dye degradation depends on the content of manganese in the samples and reaches >90%.
The distribution of the concentrations of CH
4
and CO
2
and other gases in the sediments of the Kara, Laptev and East Siberian seas was studied. A correlation was found between CH
4
and CO
2
in most ...sediment cores. The correlation coefficient R for the sediments of the Kara Sea ranges from 0.58 to 0.97 and does not depend on the gas distribution with depth. Methanogenesis in marine sediments is presumably associated with sulfate reduction, and hydrogenotrophic methanogenesis leads to an increase in CH
4
concentration against the background of high CO
2
concentration. The high concentration of dimethyl sulfide in the sediments indicates the simultaneous formation of CH
4
and CO
2
through methylotrophic methanogenesis with the participation of CH
3
SCH
3
. In the upper layers of the sediment, opposite trends in the CH
4
and CO
2
distribution can be observed. The fact that the correlation coefficients between CH
4
and CO
2
gases in the sediments of the Laptev Sea acquire both negative and positive values is probably related to the fact that gas formation processes in the upper layers of the sediment captured by short columns differ from those of deep layers.
The article deals with entrepreneurship as one of the main spheres of the national economy and an important component of its competitiveness. The role of domestic entrepreneurship in the structural ...reorganization of the economy is determined. It is determined in the irreversibility of Ukraine’s entry into the European economic system. The article analyzes the opinions of financial experts on the unpreparedness of Western banks and companies to lend to Ukrainian businesses in the context of the ongoing economic crisis and military operations. The article considers and suggests that small and medium-sized business owners use modern sources of financing for their business projects, such as franchising and crowdfunding. The author defines the essence and real content of domestic entrepreneurship and its compliance with modern civilization standards. Entrepreneurship is considered in terms of its participation in the formation of political and economic relations in the country, in the search for effective legal mechanisms to ensure the comprehensive development of small and medium-sized businesses. The author establishes the connection between entrepreneurship and the increase in the number of owners of resources and means of production. This gave impetus to the corresponding formation of the middle class in society, which is the key to political and economic stability in any democratic country. Social and societal processes and their impact on the formation of small and medium-sized businesses are outlined. The influence of business on these processes is considered from the point of view of business as a social phenomenon. Amendments and additions to some laws regulating the activities of small and medium-sized enterprises are reviewed. The main directions of development of entrepreneurship in Ukraine at the present stage are determined. It is determined that the development of domestic small and medium-sized businesses is in line with global trends in the formation of a flexible market economy and a combination of both different forms of ownership and different business models.
Applications of the plasma-electrolytic oxidation technique for the formation of magnetically active oxide coatings on aluminum and titanium are reviewed. Specimens of aluminum-, iron-, and ...tungsten-containing oxide layers on aluminum substrates with ferro- and ferrimagnetic properties are experimentally produced and studied, as well as specimens that can be remagnetized at certain external magnetic field intensities and specimens the magnetization of which is opposite to the external field. The existence of nano- and microscale crystallites, in which aluminum and metals from the electrolyte are accumulated, are found in pores of the coatings. The crystallites supposedly determine the magnetic properties of the specimens. A correlation between the Fe/Σ(W, Al) atomic ratio in crystallites and the magnetic properties of the systems studied is discovered.
Context. The analysis of stellar oscillations is one of the most reliable ways to probe stellar interiors. Recent space missions such as Kepler have provided us with an opportunity to study these ...oscillations with unprecedented detail. For many multi-periodic pulsators such as γ Doradus stars, this led to the detection of dozens to hundreds of oscillation frequencies that could not be found from ground-based observations. Aims. We aim to detect non-uniform period spacings in the Fourier spectra of a sample of γ Doradus stars observed by Kepler. Such detection is complicated by both the large number of significant frequencies in the space photometry and by overlapping non-equidistant rotationally split multiplets. Methods. Guided by theoretical properties of gravity-mode oscillation of γ Doradus stars, we developed a period-spacing detection method and applied it to Kepler observations of a few stars, after having tested the performance from simulations. Results. The application of the technique resulted in the clear detection of non-uniform period spacing series for three out of the five treated Kepler targets. Disadvantages of the technique are also discussed, and include the disability to distinguish between different values of the spherical degree and azimuthal order of the oscillation modes without additional theoretical modelling. Conclusions. Despite the shortcomings, the method is shown to allow solid detections of period spacings for γ Doradus stars, which will allow future asteroseismic analyses of these stars.
The endophenotype concept is considered as theoretical basis for the study of pathobiological mechanisms of schizophrenia and for the development of the complex of instrumental diagnostic methods. ...The contemporary state of the problem and the most significant results of the study of three neurophysiological schizophrenia endophenotypes are presented in the review: P50 auditory evoked potential suppression, prepulse inhibition of the startle reflex and antisaccade task. The current understanding of the underlying neurophysiological and neurochemical mechanisms is described for each measure. The results of the association studies of neurophysiological endophenotypes with the relevant to schizophrenia genes' polymorphisms are laid down. High degree of independence of the considered endophenotypes is demonstrated. Taking into account the data on relatively low specificity of each endophenotype to schizophrenia compared to other mental disturbances the authors pay special attention to the model of multivariate endophenotype as a scientific and diagnostic tool.
The article is devoted to the coverage of the eventful life path of A. Makarenko’s main ideological opponent – an active revolutionary, a well-known figure in national education, author of numerous ...pedagogical publications Valentina Diushen.The nature of V. Diushen's social origin and education, details of her revolutionary and educational-managerial activity, publishing activity are revealed, little-known biographical information about her family members is presented: the first husband – Borys Diushen, the second husband – Volodymyr Aussem, son – Ihor Diushen. The chronology of all known controversial moments of professional dialogue of V. Diushen and A. Makarenko is presented in detail. For the first time in the Makarenko literature, documentary evidence of A. Makarenko's reports on V. Duchen's affiliation with the Trotskyi opposition is presented.The set of found materials presents Valentina Diushen as a large-scale personality of a highly professional, active, able-bodied, and principled figure in the history of national education. However, it is the ambiguity, the contradiction of this figure that determines its opposed assessments by contemporaries.The conflict between Makarenko and Diushen must be viewed in two planes, the objective and the subjective. On the one hand, the tension of their professional relations as representatives of innovative pedagogy is evidence of the struggle that always accompanies the assertion of any new doctrine. On the other hand, both of these figures were extremely bright, original figures and, at the same time, extremely ambitious personalities. At the same time, the ambition and irresistibility of V. Diushen towards the self-confident but non-partisan head of the provincial institution were dictated by its administrative status, membership in the political elite, and metropolitan education and social background.So far, it is difficult to explain whether Diushen's opposition in any way influenced her pedagogical views, but it should be noted that A. Makarenko in his criticism of her makes a special emphasis on this circumstance.
The results are reported of the numerical experiment on evaluating a holographic method for mode selection in a shallow water area against a background of intense internal waves causing horizontal ...refraction of sound source waves. Selection of modes and reconstruction of their parameters are analyzed. The horizontal refraction effects do not lead to the identity loss of mode parameters: modes are selected, and their parameters are reconstructed. Reconstructed group velocities of the modes are very close to group velocities of the unperturbed waveguide modes.
In this paper, the results of studying peculiarities of longitudinal nonlinear oscillations of homogeneous gas (air) in closed tubes under shock-free wave conditions near the basic natural frequency ...are presented. At the resonance frequency, a continuous wave of gas pressure in time has the asymmetric form: time of compression is less than that of rarefaction. The resonance frequency being observed has in this case a lesser value than that calculated by the linear theory and coincides with the frequency determined by using the nonlinear theory (with regard to losses). Also shown is an adequate agreement between the theoretically obtained data on swing of gas pressure oscillations and the experimental results.
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