1,223 research outputs found

    Preparation and characterization of Bi26–2xMn2xMo10O69-d and Bi26.4Mn0.6Mo10–2yMe2yO69-d(Me = V, Fe) solid solutions

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    Received: 06.06.2017; accepted: 23.06.2017; published: 14.07.2017.Single phase samples of bismuth molybdate, Bi26Mo10O69, doped with Mn on the bismuth sublattice and V, Fe on the molybdenum sublattice were found to crystallize in the triclinic Bi26Mo10O69 structure at low doping levels and in the monoclinic Bi26Mo10O69 structure - at higher dopant concentration. The assumption that all Mn ions have an oxidation state of +2 was confirmed by means of magnetic measurement results analysis using Curie-Weiss law. Conductivity was investigated using impedance spectroscopy. The conductivity of Bi26.4Mn0.6Mo9.6Fe0.4O69-d was 1.2*10-2 S*cm-1 at 973 K and 2.2*10-4 S*cm-1 at 623 K, and the conductivity of Bi26.4Mn0.6Mo9.2V0.8O69-d was 2.2*10-3 S*cm-1 at 973 K and 2.2*10-5 S*cm-1 at 623 K

    General Relativistic Effect of Gravitomagnetic Charge on Pulsar Magnetosphere and Particle Acceleration in a Polar Cap

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    We study magnetospheric structure surrounding rotating magnetized neutron star with nonvanishing NUT (Newman-Tamburino-Unti) parameter. For the simplicity of calculations Goldreich-Julian charge density is analyzed for the aligned neutron star with zero inclination between magnetic field, gravitomagnetic field and rotation axis. From the system of Maxwell equations in spacetime of slowly rotating NUT star, second-order differential equation for electrostatic potential is derived. Analytical solution of this equation indicates the general relativistic modification of an accelerating electric field and charge density along the open field lines by the gravitomagnetic charge. The implication of this effect to the magnetospheric energy loss problem is underlined. In the second part of the paper we derive the equations of motion of test particles in magnetosphere of slowly rotating NUT star. Then we analyze particle motion in the polar cap and show that NUT parameter can significantly change conditions for particle acceleration.Comment: 21 pages, 6 figures, accepted for publication in Ap

    CHANGES OF THE OPTICAL PROPERTIES OF TOP-GRADE FLOUR (SEMOLINA) FROM DURUM WHEAT DURING ITS RIPENING

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    Using the rapid method of digital image analysis by the developed scanning flour analyzer the optical properties of flour (semolina) obtained in laboratory and production conditions from durum wheat of three years of harvest (2017–2019), namely the «yellowness» indicator and the color characteristic in the blue part of the spectrum, were determined. The semolina color was also evaluated by the Konica Minolta CR-410 colorimeter. It is established that the «yellowness» indicator and the color characteristic in the blue part of the spectrum did not change within the first 5 to 6 days after grinding. The change of these indicators for all the samples is observed in the period from 6 to 20 days after grinding, there with the «yellowness» indicator decreased by 25 to 40 relative units, the color characteristic in the blue part of the spectrum increased on average by 133,75 relative units. Over the next three months, there was no change of color (by both indicators). In the course of experimental work the optical properties change depending upon carotenoids content of flour (semolina) during its ripening was shown. The correlation dependence between the «yellowness» indicator of flour (semolina) and its carotenoids content is characterized by a high approximation coefficient. The dependence of the color characteristic of flour in the blue part of the spectrum on the content of carotenoids is characterized by an approximation coefficient equal to 0.9358, and is described as a polynomial equation. It shows, that with a low carotenoid content, the considered indicator is higher by an average of 1100 relative units compared to the color of samples with a carotenoid content from 0.70 to 1.21 mcg/g. At that during storage the optical properties of flour variety with the lowest carotenoids content remained practically the same. During 78 days of storage, there was no significant change of color characteristics of the industrial flour samples, studied from the eleventh day after grinding — 5–8 times higher than the average repeatability of the measurement results.Using the rapid method of digital image analysis by the developed scanning flour analyzer the optical properties of flour (semolina) obtained in laboratory and production conditions from durum wheat of three years of harvest (2017–2019), namely the «yellowness» indicator and the color characteristic in the blue part of the spectrum, were determined. The semolina color was also evaluated by the Konica Minolta CR-410 colorimeter. It is established that the «yellowness» indicator and the color characteristic in the blue part of the spectrum did not change within the first 5 to 6 days after grinding. The change of these indicators for all the samples is observed in the period from 6 to 20 days after grinding, there with the «yellowness» indicator decreased by 25 to 40 relative units, the color characteristic in the blue part of the spectrum increased on average by 133,75 relative units. Over the next three months, there was no change of color (by both indicators). In the course of experimental work the optical properties change depending upon carotenoids content of flour (semolina) during its ripening was shown. The correlation dependence between the «yellowness» indicator of flour (semolina) and its carotenoids content is characterized by a high approximation coefficient. The dependence of the color characteristic of flour in the blue part of the spectrum on the content of carotenoids is characterized by an approximation coefficient equal to 0.9358, and is described as a polynomial equation. It shows, that with a low carotenoid content, the considered indicator is higher by an average of 1100 relative units compared to the color of samples with a carotenoid content from 0.70 to 1.21 mcg/g. At that during storage the optical properties of flour variety with the lowest carotenoids content remained practically the same. During 78 days of storage, there was no significant change of color characteristics of the industrial flour samples, studied from the eleventh day after grinding — 5–8 times higher than the average repeatability of the measurement results

    Quantum Interference Effects in Slowly Rotating NUT Space-time

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    General relativistic quantum interference effects in the slowly rotating NUT space-time as the Sagnac effect and the phase shift effect of interfering particle in neutron interferometer are considered. It was found that in the case of the Sagnac effect the influence of NUT parameter is becoming important due to the fact that the angular velocity of the locally non rotating observer must be larger than one in the Kerr space-time. In the case of neutron interferometry it is found that due to the presence of NUT-parameter an additional term in the phase shift of interfering particle emerges. This term can be, in principle, detected by sensitive interferometer and derived results can be further used in experiments to detect the gravitomagnetic charge. Finally, as an example, we apply the obtained results to the calculation of the UCN (ultra-cold neutrons) energy level modification in the slowly rotating NUT space-time.Comment: 11 pages, 1 figure, accepted for publication in Int. J. Mod. Phys. D; added reference

    Political Activity of Russians: Current Trends and Resources of Media Influence

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    Authors assume that in the post-Soviet time, political consciousness among the Russians has significantly changed. Causes of this not only include general depoliticization in the society, but also a modified nature of the media influence. The research purpose is to search for reasons that cause booms and falls in the interest of the Russians in politics. The methodological framework of the research included the Verba-Pye model of engagement in politics, Lipset's conclusions about citizens' engagement in political affairs; assumptions from the LipsetRokkan model of political preferences of citizens; Scott's concept of imitation of political activism, and Bryant's conclusions about specifics of media influence on public opinion. The empirical basis of the research includes data from sociological and marketing research made by Russian centers for the study of public opinion. As a result of the research, its authors have established that country residents do not mostly show high political engagement and civil activis

    Behaviour of the Blazar CTA 102 during two giant outbursts

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    Blazar CTA 102 underwent exceptional optical and high-energy outbursts in 2012 and 2016-2017. We analyze its behaviour during these events, focusing on polarimetry as a tool that allows us to trace changes in the physical conditions and geometric configuration of the emission source close to the central black hole. We also use Fermi gamma-ray data in conjunction with optical photometry in an effort to localize the origin of the outbursts.AST-1615796 - Boston Universit

    Structure and electrical conductivity of cobalt-doped Bi 26Mo10O69

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    The existence boundaries, structures, and transport parameters of Bi 1 - x Co x [Bi12O14]Mo 5O20 ± δ and Bi[Bi12O 14]Mo5 - y Co y O20 ± δ solid solutions, which have a unique columnar structure, were studied. Electrical conductivity in these solid solutions was studied by impedance spectroscopy. © 2013 Pleiades Publishing, Ltd

    The role of educational technologies in the individualization of educational students’ activities

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    The basis of the modern student's training is the idea of individualization of his educational activities since the modern educational paradigm has designated the personality of the student and his needs as the most important link in this system. Higher educational institutions in search of effective ways of formation of competence of the future specialist using individualization of its activity use possibilities of innovative educational technologies. The purpose of the article: to consider the experience of implementation of educational technologies in the individualization of educational activities of students. The article presents an overview of the essence and importance of educational technologies used in the modern educational process, the features of their implementation and their role in the individualization of student activity. We considered the experience of implementation of educational technologies in the individualization of educational activities of students. Innovative technologies have a powerful potential in shaping the competence of future specialists. Individualization of training takes place in comfortable conditions for the teacher and the student. The teacher has the opportunity to constantly monitor the level of knowledge of the student and make timely adjustments, directing it in the right direction. When students perform tasks, the teacher carried out periodic consultations, where he covered for students the questions that appeared to them. The teacher conducted small surveys and tests, with the help of which the test of assimilation of the material was determined. The study presented in the article allowed to determine the impact of individualization of education on the level of student performance. Based on the data obtained in the course of our research, we can conclude that educational technologies provide ample opportunities for individualization of the learning process and contribute to the formation of professional competence of a specialist

    Recent outburst of the young star V1180 Cas

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    We report on the ongoing outburst of the young variable V1180 Cas, which is known to display characteristics in common with EXor eruptive variables. We present results that support the scenario of an accretion-driven nature of the brightness variations of the object and provide the first evidence of jet structures around the source. We monitored the recent flux variations of the target in the Rc, J, H, and K bands. New optical and near-IR spectra taken during the current high state of V1180 Cas are presented, in conjunction with H2 narrow-band imaging of the source. Observed near-IR colour variations are analogous to those observed in EXors and consistent with excess emission originating from an accretion event. The spectra show numerous emission lines, which indicates accretion, ejection of matter, and an active disc. Using optical and near-IR emission features we derive a mass accretion rate of ~3 E-8 Msun/yr, which is an order of magnitude lower than previous estimates. In addition, a mass loss rate of ~4 E-9 and ~4 E-10 Msun/yr are estimated from atomic forbidden lines and H2, respectively. Our H2 imaging reveals two bright knots of emission around the source and the nearby optically invisible star V1180 Cas B, clearly indicative of mass-loss phenomena. Higher resolution observations of the detected jet will help to clarify whether V1180 Cas is the driving source and to determine the relation between the observed knots.Comment: Accepted as Letter in A&A; 4 pages, 3 figure
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