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In this work, numerical simulations are used to study ambipolar organic field-effect phototransistors, in which
a spatially localized photoelectric effect can take place. This effect consists in the fact that there is a small
spatially localized photosensitive region in the transistor channel, the position of which can be controlled
by changing the gate voltage. The purpose of this work is to analyze the relationship between the form of
the field dependence of the bound electron-hole pairs (𝑒/ℎ pairs) dissociation probability and characteristics
of the studied ambipolar phototransistors such as normalized photocurrent, spatial resolution, and response
time. It is shown that the optimal form of the field dependence of 𝑒/ℎ pairs dissociation probability is
stepwise-like form, which can provide a high spatial resolution at high values of the normalized photocurrent
without degrading the response time of the phototransistor. This shape can be achieved when the organic
semiconductor has an extremely narrow distribution of 𝑒/ℎ pairs by size, described by the delta function.
Also, on the example of several distributions of various shapes, it is shown that a decrease in the width of
the distribution leads to an increase in the spatial resolution. Approaches to the selection and modification
of organic semiconductor materials that would provide the most pronounced spatially localized photoelectric
effect in ambipolar field-effect transistors are discussed.

The article is devoted to the analysis of a promising direction of historical research - the development of the military-industrial complex of the Kuibyshev region after the Great Patriotic War. The article provides a brief overview of the works analyzing the issues of the functioning of the region's military production during the war years, which became the prerequisites for creating a line of research on the post-war development of the region's military industry. The degree of study of the indicated problems in generalizing works devoted to both the history of the entire military-industrial complex of the USSR and the history of the Samara (Kuibyshev) region in the XX century is considered. The directions of special research, touching upon the development of certain branches of the military production of the Kuibyshev region after the Great Patriotic War, are determined. ; Статья посвящена анализу перспективного направления исторических исследований развитию военно-промышленного комплекса Куйбышевской области после Великой Отечественной войны. В статье приводится краткий обзор трудов, анализирующих вопросы функционирования военного производства региона в годы войны, которые стали основной для изучения послевоенного развития военной промышленности региона. Рассматривается степень изученности обозначенной проблематики в обобщающих трудах, посвященных как истории всего военно-промышленного комплекса СССР, так и истории Самарской (Куйбышевской) области в ХХ веке. Определяются направления специальных исследований, затрагивающих вопросы развития отдельных отраслей военного производства Куйбышевской области после Великой Отечественной войны.

Manganese (Mn)-and yttrium (Y)-substituted Sr-nanohexaferrites (MYSNHFs) of composition Sr1?xMnxFe12?xYxO19 (with 0.0 ? x ? 0.5) were prepared by citrate sol-gel autocombustion method. As-prepared MYSNHFs were characterized via diverse analytical techniques to determine the influence of Mn and Y cosubstitution on their microstructures and magnetic properties.57Fe Mössbauer spectra of the MYSNHFs were used to evaluate the variation in the line width, isomer shift, quadrupole splitting, and hyperfine magnetic field values. It was shown that the dopant ions could preferentially occupy the 12k, 4f2, and 2b sites. Furthermore, the observed shift in the blocking temperatures of the studied MYSNHFs towards lower values with rising Mn2+ and Y3+ contents was attributed to the overall particles size reduction. Meanwhile, the AC susceptibility of the proposed MYSNHFs revealed that the magnetic interactions were weakened with the increase in dopant contents which was ascribed to the replacement of both Sr2+ and Fe3+ ions by the Mn2+ and Y3+ dopants. © 2018 by the authors. Licensee MDPI, Basel, Switzerland. ; Information Resources Management College, IRMC; Ministry of Education and Science of the Russian Federation, Minobrnauka: 5.5523.2017/8.9 ; The authors are grateful to the Institute for Research & Medical Consultations (IRMC) of Imam Abdulrahman Bin Faisal University (IAU—Saudi Arabia) for the financial assistance to pursue this research through the Projects application number: (2018-IRMC-S-1); (2018-IRMC-S-2), and (2017-IRMC-S-3). This work was carried out with financial support in part from the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST «MISiS» implemented by a governmental degree dated 16th of March 2013, No. 211, among the leading world scientific and educational centers: grant No. ?02-2017-2-4 and additionally grants No. K4-2017-041 and No. K3-2018-026. The partial support by the Ministry of Education and Science of the Russian Federation with Government task SUSU 5.5523.2017/8.9 and the framework of the Increase Competitiveness Program of MISiS G02-2017-2-4 is appreciated. ; 2-s2.0-85059416183

The article analyzes results of an online survey (N = 2021) of young people (aged from 14 to 35 years) living in the Saratov region. The author summarizes answers related to the respondents' value orientation. It is concluded that the value identification and orientation of young people are influenced by the safe conditions of functioning of regional society, as well as global political events. In the view of young people, the values of patriotism and collectivism fade into the background, material well-being comes first, this contributes to the outflow of young people from the province to more prosperous cities and regions, which creates a lack of population reproduction potential in the region. In turn, this creates demographic problems and the replacement of the indigenous population by migrants who are not culturally adapted to local conditions. The polar worldview of young people is also revealed in relation to the special military operation, where positive and negative opinions are almost equal. In the structure of regional security, regional threats are clarified, to which the author refers destructive political activity of young people, uncertainty about the future, outflow of young people from the region, uncontrolled migration to the region of citizens of other states, corruption of local officials, and low socio-qualitative potential of the region.

This article examines the features of the political identity of provincial youth based on socio-economic differentiation. It is noted that the youth environment is not homogeneous in its socio-economic status and such differentiation in the context of a Special Military Operation, an unstable political situation, and social tension presupposes a different political identity. In turn, this leads to destructive activity of young people in relation to government officials, as well as to intergroup conflicts. This assumption formed the basis of the author's analysis in considering the possible dependence of the ideological identification of young people on their place in the social structure of society. The scientific tasks to be solved by the analysis are the understanding and conceptualization of the political and ideological orientations of modern youth in the context of socio-economic differentiation. The working hypothesis was that the least financially protected groups of young people are the most radical in relation to the authorities. Therefore, the author conditionally distinguishes two groups of young people. The first group of young people are those who have a low standard of living, suffer from a lack of social elevators and social injustice, do not have the opportunity to get a good education and are ready to change their position in society during protest actions. The second group of young people is the generation that grew up as "qualified consumers", who saw risks in reducing their consumption levels and are therefore ready for protest actions in order to defend their rights as consumers. However , the study of this problem revealed that modern youth are quite apolitical, this was shown by answers to the question about choosing an ideology whose values are closest to the respondent, as well as a rather low percentage of radically minded youth, regardless of financial situation, which does not significantly affect the political process. At the same time, in conditions of political instability and elite conflict, these groups of youth can become a destructive resource for political actors in the conflict.

The article reveals the problems of legislation in the sphere of functioning of national and cultural autonomies that affect politics both on regional and federal levels. The author notes the need to reform the legal framework for the functioning of national and cultural autonomies in the context of the national security Strategy of Russia.

The Mn3Sb metastable compound is formed at high pressure and temperature and it decomposes upon heating above 420 K into Mn2Sb and Mn. It has a cubic crystalline structure describing the Pm-3m (№ 221) space group with a lattice parameter of a = 0.400 nm. In the present work, according to the results of neutron diffraction investigations and taking into account magnetometry data, it is shown that Mn3Sb is an antiferromagnet, and a model of the magnetic structure with a triangular configuration of equal magnetic moments in magnitude is proposed. The magnetic moments of manganese atoms, constituting the basis of a unit magnetic cell, lie in the (111) plane and form an equilateral triangle. According to neutron diffraction data, the magnetic moments of manganese atoms were determined at different temperatures.

The correlation between the synthesis modes, chemical composition, crystal structure, surface microstructure, and also the mechanical properties of thin nanostructured Ni – Fe films has been studied. Thin Ni–Fe films on the Si with Au sublayer were obtained using electrolyte deposition with different current modes: direct current and three pulsed modes with pulse duration of 1 s, 10–3 and 10–5 s. It is shown that a decrease in the pulse duration to 10–5 s leads to an increase in the film elastic modulus and the hardness due to the small grain size and a large number of grain boundaries with increased resistance to plastic deformation. The effect of heat treatment at 100, 200, 300, and 400 °C on the surface microstructure and micromechanical properties of the films was investigated. An increase in grain size from 6 to 200 nm was found after heat treatment at 400 °C which, in combination with interfusion processes of the half-layer material, led to a significant decrease in hardness and elastic modulus. Ni–Fe films with improved mechanical properties can be used as coatings for microelectronic body for their electromagnetic protection.

Inorganic-based nanoelements such as nanoparticles (nanodots), nanopillars and nanowires, which have at least one dimension of 100 nm or less, have been extensively developed for biomedical applications. Furthermore, their properties can be varied by controlling such parameters as element shape, size, surface functionalization, and mutual interactions. In this study, Ni-alumina nanocomposite material was synthesized by the dc-Ni electrodeposition into a porous anodic alumina template (PAAT). The structural, morphological, and corrosion properties were studied using x-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and electrochemical techniques (linear sweep voltammetry). Template technology was used to obtain Ni nanopillars (NiNPs) in the PAAT nanocomposite. Low corrosion current densities (order of 0.5 μA/cm2) were indicators of this nanocomposite adequate corrosion resistance in artificial physiological solution (0.9% NaCl). A porous anodic alumina template is barely exposed to corrosion and performs protective functions in the composite. The results may be useful for the development of new nanocomposite materials technologies for a variety of biomedical applications including catalysis and nanoelectrodes for sensing and fuel cells. They are also applicable for various therapeutic purposes including targeting, diagnosis, magnetic hyperthermia, and drug delivery. Therefore, it is an ambitious task to research the corrosion resistance of these magnetic nanostructures in simulated body fluid. © 2020 by the authors. Licensee MDPI, Basel, Switzerland. ; Government Council on Grants, Russian Federation ; Belarusian Republican Foundation for Fundamental Research, BRFFR: Ф18Д-007 ; 20163522 ; Funding: The work was performed with support of State Scientific and Technical Program "Nanotech" (ГБЦ No 20163522), Belarusian Republican Foundation for Fundamental Research (Grant No. Ф18Д-007), Act 211 of Government of Russian Federation (contract No. 02.A03.21.0011). Additionally, the work was partially supported by the Grant of World Federation of Scientists (Geneva, Switzerland).

Bi nanocrystalline films were formed from perchlorate electrolyte (PE) on Cu substrate via electrochemical deposition with different duration and current densities. The microstructural, morphological properties, and elemental composition were studied using scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray microanalysis (EDX). The optimal range of current densities for Bi electrodeposition in PE using polarization measurements was demonstrated. For the first time, it was shown and explained why, with a deposition duration of 1 s, co-deposition of Pb and Bi occurs. The correlation between synthesis conditions and chemical composition and microstructure for Bi films was discussed. The analysis of the microstructure evolution revealed the changing mechanism of the films' growth from pillar-like (for Pb-rich phase) to layered granular form (for Bi) with deposition duration rising. This abnormal behavior is explained by the appearance of a strong Bi growth texture and coalescence effects. The investigations of porosity showed that Bi films have a closely-packed microstructure. The main stages and the growth mechanism of Bi films in the galvanostatic regime in PE with a deposition duration of 1–30 s are proposed. © 2020 by the authors. Licensee MDPI, Basel, Switzerland. ; Government Council on Grants, Russian Federation ; 2.34 ; Funding: The work was performed with support of State Scientific and Technical Program "Nanotech" (task No. 2.34), Branch Scientific and Technical Program "Nanotechnology and Nanomaterials" (task No. 1), Act 211 of Government of Russian Federation (contract No. 02.A03.21.0011). Additionally, the work was partially supported by the Grant of World Federation of Scientists (Geneva, Switzerland).

Herein, we investigated the correlation between the chemical composition, microstructure, and microwave properties of composites based on lightly Tb/Tm-doped Sr-hexaferrites (SrTb0.01Tm0.01Fe11.98O19) and spinel ferrites (AFe2O4, A = Co, Ni, Zn, Cu, or Mn), which were fabricated by a one-pot citrate sol-gel method. Powder XRD patterns of products confirmed the presence of pure hexaferrite and spinel phases. Microstructural analysis was performed based on SEM images. The average grain size for each phase in the prepared composites was calculated. Comprehensive investigations of dielectric properties (real (ε′) and imaginary parts (ε′′) of permittivity, dielectric loss tangent (tan(δ)), and AC conductivity) were performed in the 1-3 × 106Hz frequency range at 20-120 °C. Frequency dependency of microwave properties were investigated using the coaxial method in frequency range of 2-18 GHz. The non-linear behavior of the main microwave properties with a change in composition may be due to the influence of the soft magnetic phase. It was found that Mn- and Ni-spinel ferrites achieved the strongest electromagnetic absorption. This may be due to differences in the structures of the electron shell and the radii of the A-site ions in the spinel phase. It was discovered that the ionic polarization transformed into the dipole polarization. © The Royal Society of Chemistry 2020. ; 2020-164-IRMC ; 2018-IRMC-S-2 ; Ministry of Science and Higher Education of the Russian Federation ; The authors highly acknowledged the nancial supports provided by the Institute for Research and Medical Consultations (Project application No. 2018-IRMC-S-2) and by the Deanship for Scientic Research (Project application No. 2020-164-IRMC) of Imam Abdulrahman Bin Faisal University (Saudi Arabia). M. S. acknowledges the Ministry of Science and Higher Education of the Russian Federation State assignment 2020– 2022 No. FSMR-2020-0018 (Proposal mnemonic code 0719-2020-0018). The work was partially supported by Act 211 Government of the Russian Federation, contract No. 02.A03.21.0011.