bluuebunny/crossref_metadata_2025 huggingface dataset:
A computational modelling of carbon layer formation on treeing branches
Authors: Buccella Giacomo , Villa Andrea , Ceresoli Davide , Schurch Roger , Barbieri Luca , Malgesini Roberto , Palladini Daniele
Published: December 2022

Polymeric insulation employed in electrical power industry undergo irreversible and unpredictable ageing due to partial discharges (PDs). In particular, the dielectric properties of polyethylene (PE) used in high voltage cables are often compromised by the formation of electrical trees. In this work we assume that the propagation of treeing channels involves the injection of carbonic material into the gas interacting with the surface of the defect. Experimental characterizations proved that, in certain conditions, disordered graphitic carbon can form in some areas of the electrical trees, thus increasing surface conductivity and inhibiting PDs. The chemical mechanism involved in this process is yet to be clarified. Here we propose a model for this process. By means of a series of molecular dynamics simulations, we show how the chemisorption of gaseous molecules on a PE surface can lead to a bidimensional carbonic structure. The characterization of the density of states of such systems suggests that the presence of pure carbon adsorbed on the polymer causes an increase in surface conductivity.
Monitoring MR-guided high intensity focused ultrasound therapy using transient supersonic shear wave MR-elastography
Authors: Ishak Ounay , Breton Elodie , Choquet Karine , Josset Anne , Cabras Paolo , Vappou Jonathan
Published: December 2022

Objective. The aim of the paper is to propose an all-in-one method based on magnetic resonance-supersonic shear wave imaging (MR-SSI) and proton resonance frequency shift (PRFS) to monitor high intensity focused ultrasound (HIFU) thermal ablations. Approach. Mechanical properties have been shown to be related to tissue damage induced by thermal ablations. Monitoring elasticity in addition to temperature changes may help in ensuring the efficacy and the accuracy of HIFU therapies. For this purpose, an MR-SSI method has been developed where the ultrasonic transducer is used for both mechanical wave generation and thermal ablation. Transient quasi-planar shear waves are generated using the acoustic radiation force, and their propagation is monitored in motion-sensitized phase MR images. Using a single-shot gradient-echo echo-planar-imaging sequence, MR images can be acquired at a sufficiently high temporal resolution to provide an update of PRFS thermometry and MR-SSI elastography maps in real time. Main results. The proposed method was first validated on a calibrated elasticity phantom, in which both the possibility to detect inclusions with different stiffness and repeatability were demonstrated. The standard deviation between the 8 performed measurements was 2% on the background of the phantom and 11%, at most, on the inclusions. A second experiment consisted in performing a HIFU heating in a gelatin phantom. The temperature increase was estimated to be 9 °C and the shear modulus was found to decrease from 2.9 to 1.8 kPa, reflecting the gel softening around the HIFU focus, whereas it remained steady in non-heated areas. Significance. The proposed MR-SSI technique allows monitoring HIFU ablations using thermometry and elastography simultaneously, without the need for an additional external mechanical exciter such as those used in MR elastography.
Toward sub-micron pixels for short-wave infrared imaging
Authors: Kang Chang-Mo , Rabinowitz Jacob , Bianconi Simone , Liu Lining , Ulmer Melville , Mohseni Hooman
Published: December 2022

The sensitivity of infrared (IR) imagers can be significantly improved by reducing the size of photodetectors down to the diffraction limit. Emerging low-dimensional material enable submicron photodetectors, which can be diffraction limited and lead to significant sensitivity improvement in the critical short-wave IR band. However, reaching this limit requires pixel sizes smaller than the metal bumps needed for hybridization to silicon readout chips. Such tiny fragile pixels are susceptible to damages due to the mechanical pressure applied during flip-chip bonding, degrading the number of functional camera pixels. Herein, we systematically characterize the influence of the detector size on the imager pixel yield. We then introduce strategies for improving the yield of sub-micron pixels from less than half of total pixels to more than 3/4 of them. While we used a top-down fabrication for our detectors, the developed method is also applicable to bottom-up fabrication methods to make highly sensitive IR cameras based on emerging low-dimensional material such as catalyst-assisted nanowires.
Ti supersaturated Si by microwave annealing processes
Authors: Olea J , González-Díaz G , Pastor D , García-Hemme E , Caudevilla D , Algaidy S , Pérez-Zenteno F , Duarte-Cano S , García-Hernansanz R , del Prado A , Andrés E San , Mártil I , Lee Yao-Jen , Hong Tzu-Chieh , Chao Tien-Sheng
Published: December 2022

Microwave annealing (MWA) processes were used for the first time to obtain Ti supersaturated Si. High Ti doses were ion implanted on Si substrates and subsequently MWA processed to recrystallize the amorphous layer. The resulting layers were monocrystalline with a high density of defects. Ti depth profiles indicate that diffusion is avoided once recrystallization is produced. Finally, the electronic transport properties measurements point to a decoupling effect between the Si:Ti layer and the substrate. The implanted layer present also a shallow donor and very high Hall mobility.
A comparative study of ZrS2-based thin film solar cells using the SCAPS solar cell capacitance simulator
Authors: Gupta Shubhra , Shishodia Gayatri , Shishodia P K
Published: December 2022

Transition metal chalcogenides have been studied for their potential applications in optoelectronic devices such as light emitting diodes, solar cells, photodetectors, field-effect transistors, etc. Their unique structural and versatile electronic and optical properties, non-toxic chemical nature and abundance are some of the features that have attracted tremendous attention from researchers. In this study, optimised junctions formed between zirconium sulphide (ZrS2) and copper zinc tin sulphide (CZTS), copper indium sulphide, copper indium selenide and cadmium telluride absorber layers have been explored and compared using SCAPS (a solar cell capacitance simulator program) for photovoltaic applications. The impact of operating temperature, illumination intensity, series and shunt resistances on cell performance has been discussed in detail. Comparative study concluded that the Al-ZnO/ZrS2/CZTS structure presents the best efficiency of 9.72% at room temperature. Other performance parameters obtained are short circuit current density J
sc = 25.16 mA cm−2, open circuit voltage V
oc = 0.61 and fill factor FF = 68.86%. The external quantum efficiency response was examined under the AM1.5 spectrum for different device models. The simulation results suggest that n-ZrS2 can be used as an excellent buffer layer to fabricate environmentally friendly non-toxic solar cells.
Enhanced performance of InAs-based interband cascade lasers emitting between 10–13 µm
Authors: Massengale Jeremy A , Shen Yixuan , Yang Rui Q , Hawkins Samuel D , Klem John F
Published: December 2022

Interband cascade lasers (ICLs) based on the type-II quantum well (QW) active region have attracted much attention for a range of practical applications in the mid-infrared due, in part, to their low power consumption. However, extending the operating wavelength of these ICLs into the long-wave infrared region presents several challenges including the reduced thermal conductivity of the optical cladding layers and the diminished wavefunction overlap in the type-II QW. One solution to alleviate the former concern is to use InAs-based ICLs. To solve the latter problem, InAs0.5P0.5 barriers are introduced in the active region, which lowers the electronic energy level and allows for the InAs well width to be reduced at longer emission wavelengths. Here the advancement of long wavelength ICLs, made from four new InAs-based ICL wafers grown by molecular beam epitaxy, is reported. These ICLs lased in the wavelength range from 10 to 13 µm and showed significantly improved performance compared with previous ICLs, including the first demonstration of broad-area devices operating in continuous wave mode beyond 12 µm. These ICLs exhibited substantially increased output powers with reduced threshold voltages (V
th) and current densities (J
th). They operated at temperatures up to 40 K higher than previous ICLs at similar wavelengths.
A single-particle framework for unitary lattice gauge theory in discrete time
Authors: Arnault Pablo , Cedzich Christopher
Published: December 2022

We construct a real-time lattice-gauge-theory (LGT)-type action for a spin-1/2 matter field of a single particle on a

(
1
+
1
)

-dimensional spacetime lattice. The framework is based on a discrete-time quantum walk, and is hence inherently unitary and strictly local, i.e. transition amplitudes exactly vanish outside of a lightcone on the lattice. We then provide a lattice Noether’s theorem for internal symmetries of this action. We further couple this action to an electromagnetic field by a minimal substitution on the lattice. Finally, we suggest a real-time LGT-type action for the electromagnetic field in arbitrary spacetime dimensions, and derive its classical equations of motion, which are lattice versions of Maxwell’s equations.
Effective role of vacuum annealing in improving structural, optical, and electrical properties of SiO2/Ag/ZnO multilayers deposited by RF sputtering for optoelectronic applications
Authors: Qasem Ammar , Hassan Abeer A , Al-nami Samar Y , Alrafai H A , Shaaban E R
Published: December 2022

Transparent conductive thin films require multilayer coatings involving metals and dielectrics with high refractive indices. Radiofrequency (RF) magnetron sputtering technique was used to accurately fabricate the SiO2/Ag/ZnO multilayers on the corning glass substrates at 298 K to be used in Concentrating Solar Power (CSP) reflectors, solar cell, and photovoltaic applications. This method optimizes coating processes in a uniform, homogeneous manner, resulting in improved optical and electrical properties, thermal endurance, and long-term stability. The technique was used to synthesize highly translucent and conductive multilayers. The structural, optical, and electrical properties as a function of temperature in the range from 25 °C to 450 °C were detailed. The crystallite size (D

cry
), lattice microstrain (ε), dislocation density (δ), and crystallites per unit surface area (N) were calculated. The values of (D

cry
) increased while the other parameters decreased with increasing temperature. The linear optical parameters were calculated. The optical results demonstrated that temperature had an impact on the studied multilayers’ optical properties. The dielectric constants, the loss factor, the AC electrical conductivity, the exponential factor, and the activation energy for the dominant conductivity mechanism were all calculated using the capacitance and conductance pathways.
Dynamic matrix theory for resonance response of plasmonic metamaterial lattice
Authors: Liu Wanguo , Liu Beiyun , Li Xinfei , Hu Hai
Published: December 2022

In this paper, a lattice dynamics method, named M-K matrix method, is proposed to investigate the near-field resonance response of a plasmonic metamaterial lattice under an oblique incident field with an arbitrary incident angle. By considering the electric, magnetic and field-dipole interactions, we construct a dissipative many-body Lagrange model for a reference lattice. A collective forced vibration equation, with the degree of freedom equals to the number of nanoparticles in a cell, is introduced to describe the lattice resonance under a polarized field. The resonance frequencies can be conveniently obtained from the poles of transfer function matrix. Based on this elegant matrix differential equation, one can calculate the amplitude-frequency and phase-frequency responses of plasmonic lattice, and analysis the normal modes from dispersion relations. The analytical results, which are from three examples: simple square lattice, binary chain and chessboard lattice, are perfectly matched with numerical simulations in a large frequency band, proving it to be an effective tool to calculate the dynamic response of plasmonic lattice.
Repetition-rate-tunable second harmonic generation in mode-locked optically pumped semiconductor disk laser
Authors: Zhuang Bihui , Hua Lingling , Tian Jinrong , Zhang Peng , Song Yanrong
Published: December 2022

We demonstrated a repetition-rate-tunable second harmonic mode-locked optically pumped semiconductor disk laser (OP-SDL), and the tuning range was from 1.168 GHz to 1.25 GHz. The entire tuning process was continuous, and OP-SDL was always in a mode-locked working state. To the best of our knowledge, this is the first work to obtain intracavity repetition rate tunable second harmonic laser in an OP-SDL. At same time, the repetition rate of fundamental wave can be continuously adjusted from 1.16 GHz to 1.66 GHz. The central wavelengths of the pulse trains were around 971 nm, and the highest repetition rate signal-to-noise ratio was more than 60 dB, indicating that the mode-locked pulses were stable.
On the issue of wearing mechanism of abrasive wheels during rails grinding
Authors: Rakhcheev V G , Maksimov I S , Galanskiy S A , Mustafin A G , Zolkin A L
Published: December 2022

Issues related to the study and theoretical description of the mechanism of wear of abrasive grains on a grinding tool used in the machining of railway rails are reviewed in the article. Abrasive wheels often do not cope with the task of removing surface defects that partially remain on the treated surface. In this case, the rail-grinding train is forced to make several passes (3 …4 passes). This leads to a decrease in the productivity of the rail grinding process. It is noted that it is possible to achieve an increase in the productivity of grinding the rails by controlling the pressing force of the wheels to the machined surface of the rail head. It is shown that the role of the destruction of the wheel grains in the grinding of the working profile, and, consequently, the profile of the rail head remains undisclosed. These unresolved issues of the mechanisms of abrasive wheels wearing during rails grinding require their own special studies. The process of formation of the individual grain wearing surface during grinding is described. It is noted that the mechanism of wearing of abrasive wheels is predictable. In this work, theoretical studies are carried out and the process of wearing of the abrasive grain is idealized, as well as mathematical simulation of the process of wearing of an individual particle is carried out on the basis of the analysis. The size of the areas of grain wearing and the intensity of its growth is the most important factor that characterizes the wearing of the tool caused by the destruction and loss of grains from the bond.
Design of an E-Learning Course on control systems modeling for students in applied physics
Authors: Tugashova L , Bazhenov R , Vikhtenko E , Borodin I , Alekseeva L
Published: December 2022

The research aims to prepare an e-learning course on ‘Identification and Mathematical Modeling of Control systems’ for students in Applied Physics. The software systems Matlab/Simulink, SciLab/Xcos are used for working mastering of the tutorial. The training is based on scaffolding principles, i.e. gradual complication of tasks. The e-learning course is designed in Moodle. It provides easy input and output (import and export) of the course content. The paper presents characteristic properties of the offered course development, which involves many constituent elements and resources of the platform: Page, Glossary, File, Chat, Forum, Presentation, Video lecture, Assignment, Comment, Test, Book, Interactive content, Hyperlink, and Database. The piloting was conducted at Almetyevsk State Oil Institute and Sholom-Aleichem Priamursky State University, Pacific National University, and Far Eastern State Transport University in 2020-2021. The designed online course is introduced in learning based on the distance learning system of Almetyevsk State Oil Institute Digital University. The student’s knowledge and skills assessment over the above-mentioned length of studies prove the effectiveness of the electronic learning resource applied for different kinds of learning. The electronic learning resource is turned out to be useful when changing to distance learning and in the blended learning model.
Strength test of the industrial building’s load-bearing structures
Authors: Sazonova S A , Nikolenko S D , Zyazina T V , Chernyshova E V , Kazbanova I M
Published: December 2022

Experimental studies were carried out in the molding shop. Tests were carried out for brickwork materials of enclosing walls by the shock pulse method. The compressive strength grades of ceramic brick fences and cement-sand mortar were determined experimentally. When testing concrete, a non-destructive strength control method and the necessary devices were used. The concrete class was determined by compressive strength in reinforced concrete columns of the building, in reinforced concrete beams of the coating and in reinforced concrete slabs of the coating. According to the proposed methodology, verification calculations were carried out. The verification calculations showed sufficient bearing capacity of the columns and foundations of the workshop building and the coating beams for the full design load. A calibration calculation of the workshop frame was also performed, which showed sufficient strength of the entire load-bearing structures of an industrial building. The proposed methodology can be used for testing similar building materials and objects.
Statistical substantiation of the quality of training metrologists in the system of additional professional education
Authors: Simkin A Z , Mozhaeva T P , Proskurin A S , Tsareva G V
Published: December 2022

The paper discusses the basics to ensure the quality of educational parameters of training engineering specialists, including the field of metrology, within additional professional education. The parameters of the educational quality that determine the effectiveness of this activity are identified. The emphasis is placed on the educational process parameter that has a direct impact on the quality of training students within additional professional educational programs, that is educational technology used in educational activities. Scientific papers are analyzed in the field of identifying an effective educational technology that ensures the quality of training students among other equal conditions. The problems are studied that are related to the choice to implement an effective educational technology in additional professional educational program. The relevance of statistical substantiation to apply an educational technology in educational activities is proved. The procedure for substantiating the quality (effectiveness) of the educational technology based on the use of statistical methods is proposed. The expediency of using statistical tools to confirm the quality of educational technology used in educational activities is argued.
Development and improvement of technical means of protecting people from the effects of atmospheric electricity
Authors: Korolev D S , Vytovtov A V , Konchakov S A , Kargashilov D V , Odnolko A A
Published: December 2022

The article rises the current question about the need to develop a fire safety system of explosive objects (buildings, structures, buildings, industrial communications), as well as organizing assistance to local self-government bodies in the implementation of primary fire safety measures. The emphasis is placed on a fire prevention system, which includes a lightning protection system designed to protect the countryside and other objects of protection against atmospheric electricity discharges. Therefore, for proper design, control and maintenance of health, it is proposed to apply the original computer program. Which allows an express analysis of lightning protection parameters and make appropriate conclusions.
Icing waveguide strength problem
Authors: Brungardt M V , Kudryavtsev I V , Brungardt A V , Goncharova E A , Li O A
Published: December 2022

In this paper, we conduct research of the waveguide strength under icing. Icing is assumed to be uniform along the perimeter and length of the waveguide, so ice deposits is considered in the form of an equivalent increase in the density of the structure. As a result, the icing problem is reduced to the problem of gravitational bending of the waveguide. Waveguide has a thin-walled rectangular cross-section; therefore, a solution demand using the theory of plate. We model the waveguide in the form of 4 plates that made it possible to obtain an analytical solution to the problem according to the plate theory. Also, it makes possible to identify the features of the stress distribution both in length and in the height of cross-section of the waveguide and refine the results in comparison with the theory of beams. The results of analytical calculation according to the developed method is compared with the data obtained according to beam theory, which show good convergence with the data obtained according to beam theory, which showed good convergence.
Tribological properties of doped zirconium dioxide crystals under water lubrication
Authors: Alisin Valery
Published: December 2022

The issues of a ceramic plain bearing performance under friction in the water are discussed in this article. Bearing bushings made from nanostructured partially stabilized zirconium dioxide crystals doped with rare earth elements under friction on steel and ceramic shafts are investigated. The statement about the possibility of using zirconium ceramic materials in bearings of multistage submersible centrifugal pumps for oil production is substantiated. The efficiency of alloying crystals to improve crack resistance is analyzed. Particular attention is paid to the tribological properties of the bearing when using steel and ceramic shafts. The results of comparative tribological tests of samples of the studied materials, bench tests of full-scale bearing bushings carried out under water and dry friction are presented. Based on the study, it is proposed to make bushings from a zirconium dioxide crystal for working on a steel shaft. It has been established that this plain bearing can withstand the emergency mode of friction under water or dry friction for half an hour.
Influence of variants of grid bars and spiky cylinders on the cleaning effect of cotton on small waste
Authors: Rajabov Ozod , Shodiev Ziyodullo , Gapporova Mastura , Yokubov Mukriddin , Ziyodullaeva Khonzoda
Published: December 2022

The article examines the use of grid bars and spiky cylinders in a small-grained cotton ginning machine. The results of the experimental tests were also compared with the results obtained in the existing structure, and the data are presented in the tables. When the recommended grid bars were installed on a hexagon (edge length 70.8 mm), the cleaning effect of the machine increased by 2.7%, and after cleaning, the amount of small waste in the raw cotton decreased to 0.07%.
Advanced tendencies and practically oriented approach to training specialists in applied physics
Authors: Alexandrov A A , Borisov A I
Published: December 2022

The existing system of training specialists in the field of applied physics in domestic universities doesn’t allow to fully meet the needs of employers. One of the main drawbacks of the educational process in higher education institution in training future engineers is insufficient use of practice-oriented educational technologies, well-organized internships and independent work of students, real design. It does not give students an opportunity to demonstrate the competences they have acquired while studying individual disciplines of the educational program. According to experts, one of the ways to improve the quality of specialists’ training, capable of eliminating this contradiction to a certain extent, is the introduction and wider spread of practice-oriented educational technologies in engineering universities. The objective of the applied physics course is to develop skills in applying the provisions of fundamental physics to competent scientific analysis of situations which an engineer has to deal with when creating new equipment and new technologies, as well as to develop students’ natural-science worldview and familiarize them with the history of physics development and its main discoveries. As a result of mastering the course of applied physics the student should learn the basic physical phenomena and basic laws of physics; limits of their applicability, application of laws in the most important practical applications; become familiar with the basic physical quantities, know their definition, meaning, methods and units of their measurement; imagine fundamental physical experiments and their role in the development of science; know the purpose and operating principles of the most important physical instruments.
Study of a method for controlling the structural integrity of monolithic polycarbonate under cyclic loads
Authors: Bobina E A , Danilaev M P , Kuklin V A
Published: December 2022

The study of a method for controlling the structural integrity of monolithic polycarbonate under cyclic loads is presented in the article. In particular, the influence of external cyclic loads on crack formation in polycarbonate was determined. The carried out experimental studies have shown the structural changes in polycarbonate (the appearance of microdefects) can be detected by a decrease in the level of the piezoelectric voltage amplitude U compared to the initial level by ∼25% for more than 104 load cycles.
Modeling the properties of multilayer heat-reflecting screens taking into account the uncertainty of structural parameters
Authors: Storozhev V I , Bolnokin V E , Mutin D I , Sorokin S A , Minh Hai Duong
Published: December 2022

The article is devoted to the study of parametric properties of multilayer heat-reflecting screens. Special attention is paid to the parameters of shielding and heat flow absorption. The study, its numerical and analytical techniques ensure that the fuzzy input situation is taken into account. The fuzziness is generated by the variance of both the values of geometric parameters and the actual values of structural elements. The proposed analytical and numerical research techniques are applicable in a wide range of productions of thermal protective products – for the energy industry, radio electronics, aerospace instrumentation, production of building structural elements. The theory of fuzzy sets is actively applied in terms of the heuristic principle of expansion. It is the basis for regular versions of the presented models. The underlying calculations are based on fuzzy numbers that represent exogenous parameters.
Preacetylation of wood filler in composite materials production
Authors: Safin R R , Prokopiev A A , Salimgaraeva R V
Published: December 2022

The increasing swelling pressure of wood filler, occurring during the use of a composite material, leads to the formation of internal microcracks, therefore, reducing the hygroscopicity of the wood filler is an urgent task. This paper considers the wood filler preacetylation technology in wood-polymer composite materials production. Wood particles were acetylated by soaking them in acetic anhydride, followed by heating in a vacuum drying cabinet at 120°C for 40, 180, and 360 minutes. Polylactide in various binder-modified wood filler ratios was used as a polymer matrix in wood-polymer composite samples. The resulting samples were examined for moisture and water absorption. It was found that with a maximum treatment time of 360 minutes moisture and water absorption of samples with 40% wood filler content did not exceed those of a composite with 20% unmodified wood filler content, which proves the effectiveness of acetylation. The results of the research conducted allow expanding the scope of use of additive manufacturing products.
Formation of silicated layer of austenitic pipe steel with different pipe sizes
Authors: Rubtsov A V , Shermatov D N , Khabibullin A I , Yu Strokina U , Batyrgareev T D
Published: December 2022

Tubular furnaces of hazardous production facilities are unique technical devices, and serve for open fire heating of various process media to relatively high temperatures. Some of the furnaces, such as pyrolysis furnaces, hydrogen conversions are also reactors that serve to decompose the hydrocarbon feedstock into separate components. The most important element of the structure is a tubular coil. The effect of high temperatures and working media on the coil metal inevitably leads to metal degradation by forming various defects, changing the structure and mechanical properties for the worse. One of the most unfavorable moments is considered saturation of the surface layers of the metal with carbon or another - carburization of the metal. When the metal is carburized, its embrittlement occurs and the probability of brittle destruction increases. All this can lead to frequent shutdown of furnaces for repairs and significant costs. One way to contain the active diffusion of carbon into the metal may be to silicate the surface of the coil elements using different silicating mixtures, since silicon can effectively delay carbon incorporation. In this work, studies are carried out on the peculiarities of the formation of a silicated layer in fragments of pipes with dimensions of 160x6 mm, 32x2 mm, 57x4 mm made of steel 08Kh18N10T depending on the holding time in the silicating mixture.
Prevention of local corrosion of aluminum alloy pontoons in steel tanks
Authors: Yu Pechenkina M , Nasibullina O A
Published: December 2022

Over the years of existence of the oil and gas industry, increasing the efficiency of equipment at production facilities places increasing demands on operational reliability and durability. The use of aluminum alloys is due to a large range of its features and properties, one of which is the combination of high strength in combination with low density, sufficient corrosion resistance, good moulding ability by casting, pressure and cutting, the possibility of using aluminum parts in all kinds of structures by welding, soldering and other methods. It is important to bear in mind that aluminium alloys do not require regular corrosion coating during operation. It is all about the finest and extremely strong oxide film (0.00001 mm), which forms a reliable adhesion to the metal.
Features of siliconizing of pipe steel X12CrNi25-20 with various term of operation in the conditions of the reactionary furnace
Authors: Rubtsov A V , Shermatov D N , Seitzhaparov B S , Yu Strokina U , Konkova D L
Published: December 2022

Most refinery and petrochemical reaction furnaces are operated under harsh conditions characterized by high pressures, temperature, and aggressiveness of the process environment. The high temperature and features of the heated raw material contribute to the formation and deposition of coke on the surface of the furnace pipes, which through adhesion and diffusion phenomena has a negative effect and reduces the operational reliability of the entire furnace, causing such a negative phenomenon as carburization of the metal. Carburization contributes to a significant limitation of the ductility of the metal and increases brittleness, which leads to the formation of various unacceptable defects, in particular the formation of brittle cracks. The occurrence of defects of this type inevitably leads to the depressurization of the coil and, as a result, to the occurrence of emergency situations and emergency shutdown for repair. The problem of carburizing a metal can help solve the silicization of its surface layers, since silicon can serve as an effective protection for active saturation of the metal with carbon. In this regard, a relevant topic is the study of the features of the formation of a modified silicon-based surface layer in the coil tubes of a reaction furnace of steel X12CrNi25-20 with a different operating life in order to increase the reliability and reliability of the furnace during operation.
Electrical properties and Raman spectra in HoxMn1-xS solid solution
Authors: Sitnikov M N , Kharkov A M , Abdelbaki H , Cheremnykh N A , Runov R V , Mashkov P P
Published: December 2022

The conductivity of the HoxMn1-xS (0 < x ≤ 0.3) solid solution in the range of temperatures 80 K – 1000 K were measured. Step like temperature dependence and extremum conductivity at high temperature were found. The temperature dependence of Raman spectra in the frequency interval 100 cm−1 – 900 cm−1 in the 300K – 900K range temperature has been investigated in the of HoxMn1-xS solid solutions. Several oscillation modes have been detected. The intensity and frequency shift of temperature fluctuations are determined. A new Raman mode appearing at high temperature T > 660 K was established. The correlation between temperature dependencies of conductivity and frequencies and intensities of Raman modes were established. Raman spectra were explained in terms of impurities octahedral modes.
Investigation of stepped InP(001)<110> surface by the method of low energy ion scattering
Authors: Karimov M K , Kutliev U O , Otabaev M U , Khajieva I A
Published: December 2022

5 keV - energy Ne+ ions are scattered from stepped InP(001)<110> surfaces in grazing incidence. The study of a stepped surface using the ion scattering method is of great interest, since ions are scattered at large angles. For the stepped surface calculated the simple trajectories channeled ions using binary collision approximation method. Calculated energy and angle of ions, which exits from this surface channel. It indicates that at the energy distribution observe intensively peaks, which corresponded to the ions leaved surface channels formed, stepped atoms.
Transformation of the structure and adsorption properties of bentonite during physical and chemical treatment
Authors: Buntin Artem , Agliullin Vadim
Published: December 2022

The paper presents the results of studies of the effect of electromagnetic, ultrasonic and acid treatments on the structure and the adsorption index of alkaline-earth bentonite modified with nanoparticles of silicon oxide and aluminum. Studies have shown that electromagnetic, ultrasonic and acid treatments contribute to an increase in the adsorption capacity of bentonite modified with nanoparticles of silicon oxide by 5, 10, and 25%, respectively. Modification of bentonite with stabilized nanodispersed hydrosols of amorphous silicon oxide (6-10.5 nm) and crystalline boehmite (3.5-4 nm) of 0.1-0.5 wt. % with subsequent ultrasonic and microwave treatments allows to increase its adsorption index for methylene blue and the cation exchange capacity up to 40%. And during the combining with preliminary activation in suspension with sodium carbonate it allows to increase up to 80%. The increase in the adsorption properties of bentonite is due to a double increase in the homogeneity of the structure, dispersion and specific surface area of aluminosilicate particles and transformations of the phase composition. As a result, through the use of advances in the field of nanotechnology, a combining of physical and chemical effects, the technology of modifying natural aluminosilicates based on bentonite has been improved, which makes it possible to significantly increase the adsorption characteristics of materials based on it.
Ceramic materials for friction units operating under vacuum
Authors: Alisin Valery
Published: December 2022

The issues of zirconium dioxide nanostructured crystals application in friction units operating under vacuum are discussed in this article. The effect of alloying crystals with rare-earth elements on crack resistance has been investigated. The optimal amount of alloying elements to achieve the highest crack resistance has been determined. Experiments were carried out on a tribometer of reciprocating motion to determine the antifriction properties of the crystal. The influence of the time of triblogical tests on the change in the coefficient during the sliding of crystals over an alpha titanium alloy is analyzed. The optimal crystal composition for vacuum operation is proposed. Vacuum tests of a bearing consisting of a crystal bush and an alphonated titanium shaft confirmed the functionality of the friction couple. A recommendation is proposed for the application of the studied friction couples in friction units of spacecraft intended for long-term operation in open space.
Ozone treatment of wood filler in polymer building materials
Authors: Safin Ruslan , Mukhametzyanov Shamil , Salimgaraeva Regina
Published: December 2022

This paper deals with wood filler ozone treatment aimed at increasing the adhesion of binders to wood. It describes the processes of thermal and ozone treatment and presents sketches of experimental units. It provides the curves of the results of the study to determine water absorption and strength, proving the feasibility of using this pretreatment method. The proposed two-stage treatment of wood filler is relevant in the production of wood-polymer composites.
Study of osseointegration properties of multilayer coatings with a biodegradable film of flavonoid nanoaggregates
Authors: Krasnikov Alexandr , Krasnikova Ekaterina , Morozova Daria , Spirkina Natalia
Published: December 2022

Characteristics of new implant coating of materials obtained by the method of induction heat treatment and modified by flavonoids nanoaggregates are studied and the prospects for their use in dental animal implantology are presented. It has been established that for a non-toxic biofunctional coating forming on a surface of implantation materials, it is had to apply the following concentrations of substances: propolis - 1.25 mg / 1 ml, polymer - no more than 0.0001%. Research has shown that experimental implants coatings do not inhibit erythropoiesis and leucogenesis. In addition, absence of sharp dispersion in calcium, phosphorus, creatinine and urea level, recovery of primary AST, ALT activity and the minimum values of C-reactive protein in experimental group animals in early term indicate implants have not any toxic effect.
Mathematical model for determining the optimal composition of mortars for restoration of historical monuments
Authors: Tojiev Inomjon , Hamidova Mohigul
Published: December 2022

The work covers the compression strength, tensile bending and adhesion of a modified mortar developed by the authors based on local gypsum for the restoration of the Ismail Samani mausoleum and the Kalyan minaret. It has been shown that the strength of the mortar is sufficient and meets the requirements of existing building codes. The recommended compositions of the modified restoration solutions based on gypsum and their strength indicators have been identified. Compositions of modified restoration solutions that contribute to an increase in their water resistance and durability have been studied. In addition, a graphical analysis of the degree of strength of mixtures has been given and mathematical models have been developed. The optimal compositions of mixtures have been determined using mathematical modeling. Based on the results obtained, conclusions have been drawn.
Hydrogen production and green chemistry
Authors: Sidorenko Alexander , Kutkina Nina , Nazarova Nadezhda , Brykin Veniamin
Published: December 2022

This paper presents a study on the production of hydrogen and “green chemistry”. The introduction introduces the terminology and historical data, followed by the defining principles that describe hydrogen production methods using natural gas, coal, water and biomass as feedstock. Some basics of “green chemistry” are also given. The next section provides an analysis of all hydrogen production methods, the results of the analysis are recorded in a table that allows you to identify the most environmentally friendly solutions. In the conclusion it is stated that the results of the study indicated in the table make it possible to assess the compliance of each of the 13 methods for producing hydrogen with the principles of “green chemistry”, and the assessment and comments do not take into account the economic component of technologies, the main emphasis is on environmental protection.
Application of nanocomposite materials in plasmon surface resonance spectroscopy
Authors: Yatsyshen V V
Published: December 2022

The paper shows that nanocomposite materials based on a dielectric matrix with metal nanoparticles uniformly distributed in it can serve as a reference material in surface plasmon resonance spectroscopy. At certain concentrations of nanoparticles, such a nanocomposite, in contrast to the nanoparticles themselves, acquires the properties of a resonant material in which the real part of the complex permittivity takes negative values and, thus, the nanocomposite becomes surface-active. Surface plasmon polaritons can be excited at its boundary. For this reason, such a nanocomposite can be used as a reference material, similarly to the silver layer used, in the analysis of the optical properties of samples by surface plasmon resonance spectroscopy. The case of circular polarization of light incident on the structure under study is considered. The analysis of ellipsometric parameters of reflected light is carried out. The high sensitivity of the method is shown. In the range of incidence angles of 35° - 55°, the most pronounced angular dependence of the ellipsometry parameters is observed. Taking into account the analysis carried out, it is possible to suggest using these patterns in SPR spectroscopy to analyze materials in a structure containing a layer of the material under study and nanocomposites as reference elements, against which a sharp extremes of reflected light appears.
MapReduce and Apache spark: technology analysis, advantages and disadvantages
Authors: Urazmatov T Q , Sh Kuzibayev X
Published: December 2022

Nowadays, it is absolutely illogical and impossible to process big data using traditional software methods and hardware. because too much data available does not allow this. However, there are some effective ways to perform such operations. This article discusses the main problems and solutions for processing big data. Today, there are a number of technologies and algorithms that process and analyze big data. This article mainly discusses, analyzes, and summarizes the advantages and disadvantages of the MapReduce architecture and Apache spark technology, and the results are presented in tabular form.
About the method of assessing the quality of big technical systems based on the rules of subtraction of matrices of values of indicators
Authors: Bilyatdinov K Z , Krivchun E A
Published: December 2022

The article presents a basic formula and a universal table for development of structure functional models of big technical systems. The method takes into account priorities of performed functions and substructures of big technical systems, also, maximum and minimum values of basic indices of technical systems. In order to compare “ideal” and real models it is recommended to use a corresponding subtraction of matrixes of quality indices. For this purpose, matrixes of indices are sorted into two groups: the one, where the minimum value of an index is considered the best, and another, where the maximum value is considered the best. The results of matrixes subtraction make a basis for the rules of models comparison. The article demonstrates a specifically designed table for processing of the results of matrixes subtraction and calculation formulas of standardized weighting coefficients of importance for each index and a complex quality index of maintenance of the assessed systems. It also contains rules of making ratings of systems’ quality. The main positive effect from the application of the proposed method is a considerable decrease of time and resources needed for the quality assessment of systems and a possibility of software realization of a rational processing of information in the process of management of big technical systems’ maintenance.
The role of measurement and the significance of metrology in industrial production
Authors: Andreev D V
Published: December 2022

The authors of the paper consider the role of measurements and the importance of metrology in industrial production. The article deals with the issues of modern development of metrological support, in order to reliably assess the quality of products. The authors draw attention to the fact that measurements are the most important tool with which people can cognize the phenomena and objects of the entire surrounding world.
Modification of the Berlekamp-Massey algorithm for explicable knowledge extraction by SIEM-agents
Authors: Fomicheva Svetlana , Bezzateev Sergey
Published: December 2022

The article discusses the problems of applying self-explanatory machine learning models in Security Information Event Management systems. We prove the possibility of using information processing methods in finite fields for extracting knowledge from security event repositories by mobile agents. Based on the isomorphism of fuzzy production and fuzzy relational knowledge bases, a constructive method for identifying patterns based on the modified Berlekamp-Massey algorithm is proposed. This allows security agents, while solving their typical cryptanalysis tasks, to use the existing built-in tools to extract knowledge and detect previously unknown anomalies. Experimental characteristics of the application of the proposed algorithm are given.
A methodology of coupled modeling of vacuum blocks of industrial installations
Authors: Osipov Eduard , Telyakov Eduard , Ponikarov Sergey , Bugembe Daniel , Ponikarov Artem
Published: December 2022

The article presents the methodology of coupled modeling of the main blocks of a chemical-technological system operating under vacuum. The system analysis of vacuum blocks is carried out and the basic rules of technological calculation are formed, in which the evacuated technological object and the vacuum overhead system are considered as a single system with inter-dependent elements. The presented methodology was applied when calculating the vacuum block of the primary oil refining process of a mini-refinery working on fuel oil, as a result of which an integrative characteristic of the block was compiled, which takes into account the mutual influence of the vacuum system and the technological object on the residual pressure at the top of the vacuum column. The adequacy of the developed model was ascertained by comparing with industrial research data. In line with the proposed methodology, numerical experiments were carried out accordingly in which the temperature of the service liquid being fed into the pump was changed. The results of the calculations showed that, achieving the given project Pressure under the current block component setup (P= 40 mm Hg) was not possible as a reason of the increased resistance in the shell side of the condenser.