Разработка технологий получения топливных присадок из техногенных отходов производств капролактама

Currently the issues of alternative use of chemical wastes, which have significan

Electronic structure, magnetic and optical properties of intermetallic compounds R2Fe17 (R=Pr,Gd)

In this paper we report comprehensive experimental and theoretical investigation of magnetic and electronic properties of the intermetallic compounds Pr2Fe17 and Gd2Fe17. For the first time electronic structure of these two systems was probed by optical measurements in the spectral range of 0.22-15 micrometers. On top of that charge carriers parameters (plasma frequency and relaxation frequency) and optical conductivity s(w) were determined. Self-consistent spin-resolved bandstructure calculations within the conventional LSDA+U method were performed. Theoretical interpetation of the experimental s(w) dispersions indicates transitions between 3d and 4p states of Fe ions to be the biggest ones. Qualitatively the line shape of the theoretical optical conductivity coincides well with our experimental data. Calculated by LSDA+U method magnetic moments per formula unit are found to be in good agreement with observed experimental values of saturation magnetization.Comment: 16 pages, 5 figures, 1 tabl

Electric fields in plasmas under pulsed currents

Electric fields in a plasma that conducts a high-current pulse are measured as a function of time and space. The experiment is performed using a coaxial configuration, in which a current rising to 160 kA in 100 ns is conducted through a plasma that prefills the region between two coaxial electrodes. The electric field is determined using laser spectroscopy and line-shape analysis. Plasma doping allows for 3D spatially resolved measurements. The measured peak magnitude and propagation velocity of the electric field is found to match those of the Hall electric field, inferred from the magnetic-field front propagation measured previously.Comment: 13 pages, 13 figures, submitted to PR

Methodology for building the optimal test bench of software and hardware complexes of control systems

The paper considers the issue of creating unified approaches to building test stands for software and hardware control systems. A universal architecture of the test bench is proposed and the author's method of constructing optimal test stands, obtained as a result of research in the field of complex automation of the test process, is described. The algorithm of directed search for the best test stand configuration is considered by example and the results of the implementation of the proposed method are demonstrated. © Published under licence by IOP Publishing Ltd

System analysis and processing of parameters of the test bench

The paper deals with the analysis of complex technical objects - test stands of control systems. A method is proposed for evaluating the effectiveness of the test bench based on the parameters obtained using the "standard"and "automated"test stand model. The objective function for calculating the efficiency of test benches based on their parameters and determining the numerical efficiency coefficient of the testing position relative to the typical one is given. The composition of the software for implementing the proposed method is shown. © Published under licence by IOP Publishing Ltd

First-principles study of orthorhombic CdTiO3 perovskite

In this work we perform an ab-initio study of CdTiO3 perovskite in its orthorhombic phase using FLAPW method. Our calculations help to decide between the different cristallographic structures proposed for this perovskite from X-Ray measurements. We compute the electric field gradient tensor (EFG) at Cd site and obtain excellent agreement with available experimental information from a perturbed angular correlation (PAC) experiment. We study EFG under an isotropic change of volume and show that in this case the widely used "point charge model approximation" to determine EFG works quite well.Comment: 4 pages, 1 figure. Accepted in Physical Review

Observation of Néel-type skyrmions in acentric self-intercalated Cr_1+δTe₂

Transition-metal dichalcogenides intercalated with 3d-transition metals within the van der Waals (vdW) gaps have been the focus of intense investigations owing to their fascinating structural and magnetic properties. At certain concentrations the intercalated atoms form ordered superstructures that exhibit ferromagnetic or anti-ferromagnetic ordering. Here we show that the self-intercalated compound Cr1+δTe2 with δ ≈ 0.3 exhibits a new, so far unseen, three-dimensionally ordered (2×2×2) superstructure. Furthermore, high resolution X-ray diffraction reveals that there is an asymmetric occupation of the two inequivalent vdW gaps in the unit cell. The structure thus lacks inversion symmetry, which, thereby, allows for chiral non-collinear magnetic nanostructures. Indeed, Néel-type skyrmions are directly observed using Lorentz transmission electron microscopy. The skyrmions are stable within the accessible temperature range (100–200 K) as well as in zero magnetic field. The diameter of the Néel skyrmions increases with lamella thickness and varies with applied magnetic field, indicating the role of long-range dipole fields. Our studies show that self-intercalation in vdW materials is a novel route to the formation of synthetic non-collinear spin textures

Uptake of cholesterol esters being a part of the different fractions of blood plasma lipoproteins by rats organs and tissues

The paper deals with the functions of the main classes of blood plasma lipoproteins (LP) that are associated with the transport of cholesterol esters included in their composition. The aim of the study was to investigate the features of the uptake of cholesterol esters associated with plasma LP fractions (very low (VLDL), low (LDL), and high density LPs (HDL)) by rat organs and tissues, and to show the participation of various subfractions of HDL (HDL2 and HDL3) as specific cholesterol carriers in the main steroid-producing organs of rats.Material and methods. The in vivo studies with intravenous LP injection of 14C labeled cholesterol oleate (14C-OCh) associated with plasma LP fractions have been carried out.Results. Intravenous injection of a 14C-OCh) in the composition with VLDL led to the maximal mark uptake by the liver. Three times less uptake of labeled cholesterol was observed in the adrenal glands, testes and heart muscle. In other tissues radioactivity gradually decreased in the raw: spleen > lungs > kidneys > thyroid gland and adipose tissue. After the injection of 14C-OCh in the composition of LDL marked predominant uptake of the label by the adrenal glands, testes, and liver. A feature of the use of HDL as a carrier platform for 14C-OCh is the high accumulation of label in steroid-producing organs: the adrenal glands and testis. The dynamics of uptake of 14C-OCh in the composition of HDL by the adrenal glands and testes of rats in different time intervals after injection (30 min, 3, 6 and 12 h) was studied. Adrenal cells actively uptake 14C-OCh from HDL, as a result of which the radioactivity of the tissue increased rapidly and after 30 minutes almost reached its maximum. In contrast to the adrenal glands uptake of the testis was characterized by a gradual increase in radioactivity with a maximum of 6 hours and a rather sharp decrease to 12 hours from the beginning of the experiment. In vitro experiments showed the differences in the effect of HDL2 and HDL3 on the corticosterone production by the adrenal glands of rats.Conclusions. The paper presents the features of uptake of cholesterol esters by organs and tissues of rats depending on the used LP-transporter (VLDL, LDL, HDL). In addition, the results suggest that HDL3 subfraction may be the more preferred source of cholesterol for steroid synthesis in the adrenal cortex of rats compared to HDL2 subfraction

BLOOD LIPOPROTEINS AS A PLATFORM FOR TRANSPORT OF HYDROPHILIC AND HYDROPHOBIC COMPOUNDS

The paper discusses the transport functions of the main classes of blood plasma lipoproteins (LP) that are not associated with the metabolism of lipids that make up their composition. The aim of the study was to study the ability of various plasma LP fractions (very low (VLDL), low (LDL) and high density (HDL)) to interact with certain hydrophilic and hydrophobic compounds and show the role of LP as transport forms of xenobiotics in the organs and tissues of the body. Material and methods. The studies were performed with tritium-labeled cytochalasin B, benzylpenicillin, benzanthracene, benzo(a)pyrene, ultracentrifugation of human plasma LP fractions, column chromatography; in vivo experiments with intravenous injection of LP complexes with tritium-labeled benzanthracene were conducted. Results. The ability of various classes of LP to form complexes with hydrophilic (cytochalasin B, benzylpenicillin) and hydrophobic (benzanthracene, benzo(a)pyrene) compounds is shown by the method of ultracentrifugation. More than 50 % of the radioactivity of hydrophilic compounds in human blood plasma was represented in the composition of the LDL and HDL fractions, and in the composition of the VLDL fractions it was minimal – 6.3 and 5.1 %, respectively. A significant part of cytochalasin and benzylpenicillin was also present in the protein infranatant – 43.6 and 40.9 %, respectively. The distribution in blood plasma for hydrophobic (benzanthracene, benzo(a)pyrene) compounds was different. More than 80 % of the radioactivity was represented in the composition of the LP fractions. The polar protein infranatant contained 16.1 % of the radioactivity of benzantracene and 13.6 % of benzo(a)pyrene. The features of the lipophilic xenobiotics uptake by organs and tissues were shown in vivo experiments with intravenous injection of complexes of LP with tritium-labeled benzanthracene to rats. The highest specific radioactivity was found in the liver and adrenal glands after the intravenous injection of 3H-benzanthracene in the composition of VLDL and LDL. Twice less uptake of the labeled drug was observed in the testis and kidneys. Radioactivity decreased in the series: lungs,adipose tissue, thymus, heart, and spleen. A feature of the use of HDL as a platform for 3H-enzanthracene is the intense accumulation of lipophilic xenobiotics in steroid-producing organs: the adrenal glands and testis. Conclusion. The results obtained allow us to consider the real possibility of using blood plasma PL as transport platforms for hydrophilic and hydrophobic compounds into the cells of organs and tissues

Обработка сигналов ЭКГ с помощью вейвлет-анализа: диагностические возможности

The problem of recognition and classification of biomedical signals is a complex problem related to the interdisciplinary field of computer science and medicine. Within the framework of the project implementation of the development of the new defibrillation equipment, it is necessary to solve the problems of analyzing biomedical signals of the electrocardiogram to obtain a diagnostic solution with the possibility of assigning a specific condition to the pathological condition of the patient. This article presents the analysis of electrocardiogram signals, considering the technical aspects of the analysis of multicomponent signals, and describes the diagnostic possibility of wavelet analysis of ECG signals. The paper considers the limited tools of analyzing the electrocardiogram signal, in particular, limitation of parametric data. Wavelet analysis may significantly expand the analysis of signals and transfer them into the time-frequency domain. Thus, the use of various basic functions of the wavelet transform leads to the determination of the additional diagnostically significant information formalized in the parameters extracted from the wavelet scalogram. Chupov A. A., Zhdanov A. E., Rakhmatullov F. K., Rakhmatullov R. F., Dolganov A. Yu. ECG Signals Processing by Using Wavelet Analysis: Diagnostic Capabilities. Ural Radio Engineering Journal. 2021;5(4):337–352. (In Russ.) DOI: 10.15826/urej.2021.5.4.001.Задача распознавания и классификации биомедицинских сигналов является комплексной задачей, относящейся к междисциплинарной области компьютерных наук и медицины. В рамках реализации проекта по разработке нового деффибрилляционного оборудования необходимо решить задачи анализа биомедицинских сигналов электрокардиограммы для получения диагностического решения с возможностью отнесения конкретного состояния к патологическому состоянию пациента. В настоящей статье представлен анализ сигналов электрокардиограммы, учитывающий технические аспекты анализа многокомпонентных сигналов, также описана диагностическая возможность вейвлет-анализа сигналов. Учитывая ограниченный инструментарий анализа сигнала электрокардиограммы с точки зрения набора параметрических данных, вейвлет-анализ позволяет значительно расширить анализ сигналов и перейти в частотно-временную область. Таким образом, использование различных базисных функций вейвлет-преобразования позволяет определить дополнительную диагностически значимую информацию, формализованную в параметрах, извлекаемых из вейвлет-скалограм. Чупов А. А., Жданов А. Е., Князев С. Т., Рахматуллов Ф. К., Рахматуллов Р. Ф., Долганов А. Ю. Обработка сигналов ЭКГ с помощью вейвлет-анализа: диагностические возможности. Ural Radio Engineering Journal. 2021;5(4):337–352. DOI: 10.15826/urej.2021.5.4.001.