1,223 research outputs found
Preparation and characterization of Bi26–2xMn2xMo10O69-d and Bi26.4Mn0.6Mo10–2yMe2yO69-d(Me = V, Fe) solid solutions
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
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
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
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
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
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
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
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
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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