bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a concept for the production of wheat snacks with the elimination of gluten by the biocatalysis
Authors: Sharikov A. Y. , Sokolova E. N. , Amelyakina M. V. , Yuraskina T. V. , Ivanov V. V. , Serba E. M.
Published: March 2021

The increase in the number of cases of allergic reactions and celiac disease is an important problem. The solution to this problem is the search and development of relevant and effective ways to eliminate gluten. Specific amino acid sequences glutamine and proline determine the resistance to protease hydrolysis of the structural domains of gluten fractions. The analysis of the literature data showed that an alternative to the gluten-free diet is the use of biotechnological methods for modifying ingredients containing gluten. Such methods include the use of leavens on the base of lactic acid bacteria or enzyme preparations containing peptidases specific to gluten biocatalysis. In addition, the pretreatment of raw materials by extrusion cooking contributes to an increase in the degree of gluten hydrolysis. The effect of the thermoplastic extrusion and various enzyme systems containing proteases, amylolytic, cellulolytic and hemicellulolytic enzymes on the changes in the molecular weights of wheat protein fractions was studied. It was found that extrusion as a factor of protein modification significantly affects the proteolysis of wheat proteins using enzyme systems of different substrate specificity. The most effective hydrolysis was shown by the use of a complex enzyme preparation Amyloprotoorizin. including The effect was also noted after bioconversion of non-extruded wheat. An algorithm for the technology of wheat snacks based on the processes of extrusion and biocatalysis of proteins with specific proteases for the elimination of gluten is devepoped. The practical implementation of the technology will make it possible to obtain ready-to-eat snacks, which will be investigated for the preservation or elimination of antigenic properties during clinical trials.
The study of patterns of inhibition native microflora of raw materials under the influence of ultraviolet radiation with different processing intensity
Authors: Kolokolova A. Y. , Iliukhina N. V.
Published: March 2021

Ultraviolet radiation has long proven itself as a technological process that allows you to reduce a significant amount or completely inhibit unwanted microorganisms, however, this technology is mainly used for disinfection of air and surfaces in industrial enterprises. The use of food processing with ultraviolet light is poorly developed, this is due to a number of limitations, one of which is the small depth of penetration of ultraviolet radiation. This circumstance introduces a number of restrictions and requires additional research for the active introduction of UV radiation in the food industry. The aim of the work: to study the dynamics of inhibition of native microflora of raw materials during UV treatment with various doses; to determine the degree of development of residual microflora during storage of UV-treated food products. Objects of research: model media containing native microflora of raw materials and fresh mushrooms. An improved UV treatment mode is proposed to reduce the surface injury of fresh mushrooms and ensure their microbiological stability of champignons during storage. The obtained results allowed us to establish the regularities of inhibition of native microflora on the surface of model media and fresh mushrooms depending on the distance to the UV radiation source, the time of irradiation, and the accumulated dose. It is noted that the dynamics of inhibition of native microflora on the surface of model media is not linear, and "Plateau" zones are marked. When developing a technology for processing fresh mushrooms, it is recommended to use a UV source with an accumulated radiation dose of 500 Dg/m2.
Analysis of experimental data on the kinetic characteristics of milk whey purification using ultrafiltration elements of BTU 05/2 type
Authors: Rodionov D. A. , Lazarev S. I. , Polyansky K. K. , Eckert E. V. , Polushkin D. L.
Published: March 2021

The paper presents the results of experimental data on the kinetic characteristics of ultrafiltration tubular elements, such as the output specific flow, retention coefficient, diffusion permeability coefficient, distribution coefficient. To study the purification of milk whey, we used tubular ultrafilters BTU 05/2 with membrane material fluoroplast (F), polyethersulfone (PESF), polysulfone (PS). For theoretical calculation of the retention coefficient, output specific flux, diffusion permeability coefficient, distribution coefficient, mathematical expressions were developed and empirical coefficients were obtained. The developed mathematical expression describes the experimental data with good reliability. The obtained experimental and calculated data can be used with high reliability in calculating mass-transfer fluxes of substances through a semi-permeable membrane, as well as in engineering methods for calculating and predicting efficiency, and using membrane processes for concentrating serum. The protein concentration in real milk whey was determined by formol titration. On the basis of the studies carried out, the dependence of the growth of the output specific flow on pressure was established, that the optimal pressure for concentrating milk whey on the ultrafiltration membranes we have chosen is 0.25 MPa. For three types of ultrafilters, the experimental value of the coefficient was within 99% for protein. For the theoretical calculation of the retention coefficient, a program in the MAXIMA language was developed and registered. Due to the method of applying the membrane to the reinforcing element, the membrane material polyethersulfone (PESF) and polysulfone (PS) have a substrate, due to which they sorb more substances on themselves, because of this, the diffusion permeability coefficient and the distribution coefficient are much higher than that of a filter element with membrane made of fluoroplastic (F), which does not have a substrate.
Production of high-protein biscuits for people with increased physical activity
Authors: Yegorova S. V. , Slavyanskiy A. A. , Postnikova T. A. , Ustinova L. V. , Rostegaev R. S.
Published: March 2021

People whose professional activity is associated with high energy consumption have a completely different lifestyle, unusual for the average person engaged in mental activity. They are directly related to one thing in common - high levels of physical activity. This leads to a large expenditure of the body's own energy and the breakdown of muscle tissue. To maintain the optimal state of a person during a period of intense activity, it is necessary to replenish energy costs in order to avoid the development of an extreme state, which is characterized by a severe state of the body, which develops under the influence of extreme emergency factors of the external and internal environments and is characterized by significant disorders of the body's vital functions. The article discusses issues related to rations for people with increased physical activity in extreme situations. Despite the fact that on the food market for people with increased physical activity there is a wide range of various snacks that are part of pocket and dry rations, one of the important tasks is to develop a modern food product that provides an increase in nutritional value. The existing rations are of insufficient nutritional value. The solution to this problem is possible through new technologies. The most promising are finely ground mixtures of various vegetables and fruits in combination with grain products. The creation of a new product in the form of a mixture for biscuits will expand the range of functional products and increase the profit of enterprises, since sales of such products in 2019 amounted to 274 billion rubles, which is 16 billion rubles more than in 2018. Biscuits from a multicomponent mixture with a high-grade protein in the composition will allow you to quickly restore the energy consumption of highly active people.
Applying lean manufacturing technologies to optimize ambulance operations amid the spread of COVID‑19
Authors:   Siberian State Medical University, Deev I. A. , Kobyakova O. S. ,   Federal Research Institute for Health Organization and Informatics of Ministry of Health of the Russian Federation, Babeshina M. A. ,   OGAUZ " Polyclinic No. 1», Baranovskaya S. V. ,   Siberian State Medical University, Boykov V. A. ,   Siberian State Medical University, Masunov V. N. ,   RSBHI «Medical sanitary station № 2», Milkevich M. N. ,   OGBUZ " Bureau of Medical Statistics», Rodionov N. V. ,   OGAUZ " Ambulance Station», Suvorova T. A. ,   Siberian State Medical University, Taranov A. A. ,   Department of Health of the Tomsk region, Shibalkov I. P. ,   Siberian State Medical University
Published: April 2021

The pandemic of new coronavirus infection COVID‑19 has become a serious challenge for the national health systems, including Russia, setting ambitious goals aimed at preventing the spread of infection and maintaining the availability of medical care in environment of increasing pressure. The aim of the study was to develop, based on the principles of lean production, a set of measures to increase the availability of emergency medical services for patients diagnosed with or suspected of a new coronavirus infection COVID‑19 in the Tomsk Region. Standard tools of lean manufacturing are applied to the work process of the admission department of the respiratory center in RSBHI «Medical sanitary station № 2». As a result of implementation of target state map, which provides for the optimization of process of transferring a patient diagnosed or suspected of a new coronavirus infection COVID‑19 to admission department, a positive dynamics of local (5.4 times increase in the proportion of calls completed within 15 minutes after the patient was delivered to the admission department) and system (an increase of 1.3 times in the proportion of calls with the time the ambulance team reaches the patient within 20 minutes) indicators of the ambulance service was achieved. The study confirms the effectiveness of lean manufacturing tools for optimizing the work of ambulance and allows us to recommend them for use in a pandemic and other risks of emergency.
Research of the efficiency of the one-step process for producing carbon steels on the territory of modern Belarus in the pre-industrial period. Foundry production and metallurgy
Authors: Andreev D. V.
Published: March 2021

The article describes experiments on the reconstruction of the technology of the one-step process of obtaining iron-carbon alloys in furnaces based on archaeological sources. It contains the description of furnace design, metallurgical process technology and raw materials preparation. The process of refining the iron bloom by forging is described. Scientifically grounded assumptions are made about possible technological methods of obtaining steels in the pre-industrial period on the territory of modern Belarus.
Investigation of the processes of dust processing gas cleaning of steelmaking industries
Authors: Rimoshevsky S. L. , Prokopchuk D. A. , Golub D. M.
Published: March 2021

The article deals with the issues of processing of dust from electric steelmaking production by the method of thermodynamic extraction of iron, zinc and lead in order to reduce the environmental impact and increase the resource base of the industry. The paper presents various methods of zinc extraction from dust and gas purification, thermodynamic calculation of the decomposition and reclaiming of zinc ferrite.
Interaction of laser radiation with the material during production powders and fibers
Authors: Chernichenko Y. D. , Vereschagin M. N. , Tselueva S. N. , Tseluev M. Yu.
Published: March 2021

The effect of laser radiation on a solid body leads to a change in the temperature field of the processed substance. The nature of heating, which is determined by the rate of change in temperature and temperature gradients, is different depending on the properties of the processed material and processing conditions.

The main physical parameters of the process of laser processing of solids are the specific power of the absorbed laser stream 104–109 W/cm2 and the interaction time of the metal with the beam – 10–5–10–8 s. When such radiation pulses interact with the surface, an instantaneous explosive melting of a part of the material occurs and the substance surrounding the surface is transferred to the plasma state. The subsequent expansion of the plasma is accompanied by the appearance of a shock wave with a peak pressure of 1–10 GPa, which acts on the material, and the metal is dispersed.

The mathematical problem of heating and melting a cylindrical plate with a laser light flux that normally affects its surface is solved. this problem is described by a system of thermal conductivity equations in three sections of the heated plate, which are characterized by the time factor of the laser radiation effect on the substance 1) 0 ≤ t ≤ tm; 2) t > tm; 3) tm < t ≤ th  (here tm, th is the time moment corresponding to the beginning of the formation of the liquid phase and the end of the melting of the plate, respectively).

The calculated dependences of changes in the surface temperature of metal alloys X18N10T, X15N60 during the action of a laser radiation pulse with a duration of τ=5 ms are presented. The presence of a phase transition associated with metal melting (an inflection in the curves) leads to a temporary decrease in the rate of temperature growth. The distribution of temperature fields causes a significant heterogeneity in the distribution of temperature over the thickness of materials, which reaches 2000 °C or more depending on the thickness of the metal and the conditions of exposure. The temperature curves of the surface heating repeat the shape of the pulse, and the temperature of the rest of the metal has a nonlinear tendency to increase with the output to the asymptote.

It is established that the process of explosive metal sputtering requires heating the volume of the material above the melting point at a thickness of 300–350 microns and an impact energy of 7–8 J. Reducing the level of energy impact to 5–6 J and increasing the thickness of the workpiece more than 500 microns does not provide the distribution of temperature fields required for the implementation of the spraying process.
Neutralization of solvent vapors of brand 646 by the adsorption-catalytic method
Authors: Panasyugin A. S. , Masherova N. P. , Tsyganov A. R. , Pavlovsky N. D.
Published: March 2021

The aim of the paper is investigation of neutralization of solvent vapors of the brand 646 by an adsorption-catalytic method. The adsorption-catalytic method includes the following stages: adsorption of the solvent components by adsorbent, thermal desorption and periodic flameless catalytic oxidation of organic substances to carbon dioxide and water. Synthetic zeolite of the NaX brand was used as a sorbent, catalyst was porous Al2O3/SiO2 ceramic foam material with an active catalytic phase. Solvent contains aceton, toluene, butylacetate, ethanol, ethyl cellosolve, n-butanol. It is shown that the value of the sorption volume of zeolite for each class of compounds depends on the certain factors: the length and structure of the carbon skeleton, the position of the hydroxyl group (for alcohols and esters), number of methyl groups in the molecules (for benzene derivatives). The conversion of the mixed solvent components was 65.4–90.1 %.
Equipment and technologies for the production and use of nanostructured materials
Authors: Vityaz P. A. , Nikalaichyk Yu. A. , Rovin S. L. , Svidunovich N. A. , Kuis D. V.
Published: March 2021

This article is a continuation of the series devoted to the creation and application of nanomaterials and nanotechnologies in modern industry in general and in metallurgy, materials science and foundry production in particular. The article deals with the choice of equipment and the development of effective methods for obtaining nanomaterials. Examples of the application of the developed equipment, technologies and materials obtained in the Republic of Belarus and abroad are given.
Analysis of the microstructure of wear resistant chrome cast irons after heat treatment
Authors: Jumaev A. A. , Baranovsky K. E. , Mansurov Yu. N.
Published: March 2021

At the Navoi Mining and Metallurgical Combine, which uses a large number of machine parts for mining operations, the issue of optimizing the compositions of wear-resistant chromium cast irons while maintaining their operational characteristics has arisen. The paper presents the results of studying the phase composition of the cast alloy, as well as the effect of heat treatment of cast iron with a high chromium content on its structure and properties. As heat treatment operations, quenching in various modes and low tempering were used. The study made it possible to systematize the known literature data on the heat treatment parameters of a group of wear-resistant chromium cast irons, as well as to optimize their heat treatment modes for parts operating in mining and processing industry.
The results of the tasks of the subprogram “Мetallurgy» obtained in 2016-2020 and prospects for the years 2021–2025
Authors: Vityaz P. A. , Tolstoy A. V.
Published: March 2021

The main results of the tasks of the subprogram “Metallurgy” obtained by the organizations of the National Academy of Sciences of Belarus, the Ministry of Education and the Ministry of Industry of the Republic of Belarus are presented. Their contribution to the solution of scientific and practical problems in the field of metallurgy is shown.

The article presents promising developments proposed for implementation in 2021–2025, aimed at optimizing existing foundries, improving the quality of products, reducing of production costs, and ensuring maximum utilization of foundry capacities.
Production of cast iron during the melting of mineral raw materials in coke cupolas
Authors: Rovin S. L. , Rovin L. E. , Jaranov V. A.
Published: March 2021

In the production of mineral raw materials in cupolas, as a by-product and harmful product, a significant amount of cast iron (up to 3 % of the raw material) is formed and, as a rule, thrown into the dumps. The article presents technical solutions that ensure the separation of mineral melt and cast iron. In addition, the article describes the results of optimizing the design of ladders used for draining liquid metal from the mineral wool cupola and transporting it. The resulting cast iron ingots can then be used as a charge in the smelting of branded cast alloys.
Method of physical simulation of macro processes of solidification of castings on transparent models and liquids.
Authors: Marukovich E. I. , Stetsenko V. Yu. , Stetsenko A. V.
Published: March 2021

The technique of physical modeling of macro processes of solidification of castings on transparent models and liquids has been developed. The model liquids may be water with different salt contents. Glass bottles can be used for transparent models. Thermal insulation of the top of the model is required. The developed technique allows to investigate the effect of dissolved gases on the microstructure of castings. It has been shown that gases dissolved in liquids have a direct effect on the solidification process and its kinetics. It has been shown that hot water containing less dissolved air than cold water solidifies in the freezer faster than cold water.
Ausferritic (bainitic) cast iron: Harmonization of international standard ISO 17804 in application to the conditions of Belarus
Authors: Pokrovskii A. I. , Khina B. B. , Tolkacheva O. A.
Published: March 2021

The experience of the Physico-technical Institute (PhTI) of the National Acdemy of Sciences of Belarus in the harmonization of international standard ISO 17804 (Founding – Ausferritic spheroidal graphite cast irons – Classification) and development of the Belorussian analogue STB ISO is described. The reasons for the choice of austempered ductile iron (ADI) as an object for standard harmonization are presented: it is the most promising cast iron in comparison with gray and classical ductile iron. The work procedure on harmonization is described: how to include the task into the State Plan on standardization, specificity of translation of the text, peculiarities of with state organizations responsible for approbation of standards such as Belorussian Institute for Standardization and Certification (BelGISS) and State Committee on Standards (Gosstandart), writing a summary of external reviews, working with critical comments from potential users. It is outlined that any foreign standard does not exists independently but is closely connected with at least 10 to 20 other standards. Thus, harmonization necessitates coordination with other standards and sometimes even with handbooks by adding annexes to the main text. The importance of a proper choice of the standard status is outlined: identical (ID) or modified (MOD). Developing an identical standard is prestigious but difficult because is requires harmonization of all the referenced standards, which is a very labor-consuming procedure. It is argued that the most suitable is ‘intermediate’ variant: adopting the authentic text of the international standard (in high-quality translation) but with annexes reflecting national specificity in this area. As a result, a harmonized standard is developed which, for the first time in Belarus, standardize the tensile strength of 800 MPa in combination with the elongation of 10 % and the tensile strength of 1400 MPa in combination with the elongation of 1 % for cast irons.

The annual demand for ADI in Belarus is estimated as about 10,000 ton. It is shown that in Belarus, where about 60 industrial enterprises have a foundry and almost every engineering plant has a heat-treatment shop, austempered ductile cast (ADI), which features a high strength, can successfully compete with rolled steel in certain applications.
Effect of micro alloying of steel with niobium on the mechanical properties of heat-strengthened rebar
Authors: Posti A. I.
Published: March 2021

One of the most effective micro-alloying elements in the production of class 500 fittings is vanadium. However, the production technology is multi-stage and expensive, so the use of ferrovanadium makes the production of vanadium-containing fittings for mass use unprofitable. In this regard, it is necessary to reduce the cost of finished products by replacing ferrovanadium with ferroniobium while preserving all the mechanical, physical and operational characteristics of the metal.

Objective: to determine the effect of the quantitative content of niobium in steel in the production of hot-rolled rebar S-500WC in coils at the mill 370/150 of OJSC “BSW – Management Company of the Holding “BMK” in accordance with the requirements of the Israeli standard SI 4466-3:2013 at various temperature and speed parameters of rolled products. The normalized mechanical properties of s-500WC reinforcing steel of all profiles (No. 8–16) in accordance with THE requirements of si 4466-3:2013 are: yield strength – 500–650 MPa, ductility – 1.15–1.35, elongation of – at least 11 % and total elongation at break of – at least 7.5 %.
Identification of reasons for non-compliance of mechanical properties in boron-containing steel parts
Authors: Sidorenko T. I. , Voznaya V. I. , Radionov A. V.
Published: March 2021

Fasteners are widely used as machine parts, structures and mechanisms. Medium-carbon alloy steels and boron-containing alloy steels are used as materials in production. Boron-containing steels have a good combination of strength and plastic properties, as well as a high level of hardenability. This article describes the research work carried out in the laboratory, and considers the reasons for obtaining low values of physical and mechanical parameters of parts manufactured at competitive enterprises. The qualitative characteristics of the metal are determined. The results of chemical, physical-mechanical and metallographic tests, as well as the results of the chemical composition of non-metallic inclusions are presented. The reasons for the discrepancy of mechanical properties in boron-containing steels are considered. The dependence of the introduction of chemical elements into steel: nitrogen, titanium, aluminum is determined. The possibility of evaluating the content of “effective boron” at OJSC “BSW” – the Management Company of the Holding “BMC” is described. The mathematical model used at OJSC “Oskol electrometallurgical combine”, which allows to carry out a theoretical calculation of the value of “effective” boron, is described. Recommendations for improving the technological process of smelting boron-containing steels are given.
Determination of phosphorus mass fraction in steels of plasma atomic emission spectrometry
Authors: Makarov V. A. , Savosteenko T. K.
Published: March 2021

A method for measuring the mass fraction of phosphorus in steels by atomic emission spectrometry with the inductively coupled plasma (AES-ICP) has been developed. Possibilities of atomic emission spectrometers of iCAP series for determination of phosphorus in steels allowing to reduce considerably duration of the analysis and to increase its profitability in comparison with chemical methods of the analysis are investigated. A method of decomposition of steel for the complete transfer of phosphorus into solution is proposed. The possibility of software spectrometers “iTeva” in the analysis by the method of relative concentrations. Calibration of the spectrometer was carried out on aqueous solutions with a known concentration of phosphorus using the method of relative concentrations. For the preparation of calibration solutions, chemically pure salt was used. The analytical line free from spectral overlays is selected. A good correlation of the calibration graph is obtained. The correctness of the determination is confirmed by the analysis of standard samples and comparison with the results of the determination in accordance with the chemical method. The developed technique is used in determining the mass fraction of phosphorus in steels. Validation of the methodology was carried out. iCAP spectrometers can be used to determine the mass fraction of phosphorus in steels.
Particularities of metrological control of non-contact systems for measuring the geometric dimensions of metal products.
Authors: Daineko O. V. , Kalinovskaya L. F. , Besseemonov N. V.
Published: March 2021

OJSC “BSW–Management Company of the Holding “BMC”, non-contact systems for measuring the outer diameters of products are widely used for measuring geometric dimensions. Diameter measurement systems are used to obtain reliable, true and accurate measurements. The method that provides continuous and non – contact control of these systems is the light -and – dark method of measuring the diameter.

To ensure the reliability of the measurement results, the diameter measurement systems must undergo metrological control – calibration. Calibration is carried out according to the developed methodology, which specifies the order of work, requirements for standards, processing of measurement and evaluation results, and registration of calibration results. To assess the extended uncertainty, a mathematical model is created that takes into account all the corrections that affect the result of the assessment, each of which is subjected to a thorough analysis.

Calibration of diameter measurement systems allows to evaluate their real deviations in operating conditions, which allows to ensure the accuracy and reliability of measuring the geometric dimensions of metal products at all stages of its production.
The ways to increase the durability of cutting tools (sintered carbide knives) in the production of steel fiber
Authors: Novikov M. F. , Kozyreva Yu. I.
Published: March 2021

One of the ways to increase the strength and reliability of building structures is the use of steel – fibre reinforced concrete. Steel – fibre reinforced concrete has significant advantages over conventional concrete. A high degree of resistance to cracking contributes to an increase in such physical and mechanical parameters as compressive, tensile and bending strength, water resistance, frost resistance, resistance to water and chemical penetration. In steel – fibre reinforced concrete, steel – fibre is used as a reinforcing material, evenly distributed over the volume of concrete.

In the process of steel – fibre production, the fiber is cut with carbide knives. The article deals with the issues of increasing the wear resistance of carbide knives used for cutting steel – fibre, and suggests ways to increase the durability of cutting tools. The influence of the quality of tungsten-cobalt hard alloy on the wear resistance of knives is analyzed, and a knife attachment device is developed.
Design of Peltier Element Based on Semiconductors with Hopping Electron Transfer via Defects
Authors: Poklonski N. A. , Vyrko S. A. , Kovalev A. I. , Anikeev I. I. , Gorbachuk N. I.
Published: March 2021

The study of thermoelectric properties of crystalline semiconductors with structural defects is of practical interest in the development of radiation-resistant Peltier elements. In this case, the spectrum of energy levels of hydrogen-like impurities and intrinsic point defects in the band gap (energy gap) of crystal plays an important role.

The purpose of this work is to analyze the features of the single-electron band model of semiconductors with hopping electron migration both via atoms of hydrogen-like impurities and via their own point triplecharged intrinsic defects in the c- and v-bands, as well as to search for the possibility of their use in the Peltier element in the temperature range, when the transitions of electrons and holes from impurity atoms and/or intrinsic defects to the c- and v-bands can be neglected.

For Peltier elements with electron hopping migration we propose: (i) an h-diode containing |d1)and |d2)-regions with hydrogen-like donors of two types in the charge states (0) and (+1) and compensating them hydrogen-like acceptors in the charge state (−1); (ii) a homogeneous semiconductor containing intrinsic t-defects in the charge states (−1, 0, +1), as well as ions of donors and acceptors to control the distribution of t-defects over the charge states. The band diagrams of the proposed Peltier elements in equilibrium and upon excitation of a stationary hopping electric current are analyzed.

A model of the h-diode containing hydrogen-like donors of two types |d1) and |d2) with hopping migration of electrons between them for 50 % compensation by acceptors is considered. It is shown that in the case of the reverse (forward) electrical bias of the diode, the cooling (heating) of the region of the electric double layer between |d1)and |d2)-regions is possible.

A Peltier element based on a semiconductor with point t-defects is considered. It is assumed that the temperature and the concentration of ions of hydrogen-like acceptors and donors are to assure all t-defects to be in the charge state (0). It is shown that in such an element it is possible to cool down the metal-semiconductor contact under a negative electric potential and to heat up the opposite contact under a positive potential.
Femtosecond System with Pulse Pumping of Seed Laser and Amplifier by Using a Single Power Unit
Authors: Tikhomirov S. A.
Published: March 2021

For several decades development of methods for generating ultrashort pulses has been an  independent urgent scientific and technical problem. There is a constant improvement both in the methods of such pulses receiving and in methods of their use. The aim of this work was to investigate the possibility of realizing the coordinated  operation  of  two  fundamentally  different  types  of  pump  lasers for the femtosecond oscillator and amplifier based on one single-lamp laser head and to create on this basis a compact high-power femtosecond system with pulsed pumping and one power unit.

The practical implementation of two types of pulsed lasers (nano- and picosecond ones operating, respectively, in Q-switch and modelock regime) on a single laser head with two active elements and one pump lamp is carried out. The required synchronization in time the pump pulse femtosecond amplifier formation and quasi-stationary region of generated pulses in the output radiation of a femtosecond Ti:sapphire is obtained.

On this basis a compact, pulse pumped monoblock laser system has been developed that can generate femtosecond pulses with a duration of 50–150 fs with an energy up to 1 mJ and a high enough pulse repetition rate (up to 1 kHz which is determined by the type of laser head and pump unit used). In the developed laser system a compact scheme of a stretcher-compressor with a single common diffraction grating is used.

Laser systems of this type characterized by a relatively low cost due to the use of a single power supply unit for simultaneous pumping  of  the  amplifier  and  oscillator,  as  well  as  lower  requirements for the quality of optical elements and usage conditions due to the pulse mode of operation, are quite practical and  can  be  used  both  in  scientific research  in  the  field  of  ultra-high-speed kinetic spectroscopy and nonlinear optics, as well as in numerous technical applications, particular in the precision processing of materials, as optical  simulators  of  the  action  of  heavy  charged  particles  in  testing the radiation resistance of integrated circuits and electronic modules.
Optimization of the Emitting Coil of a Hardware-Software Complex for Study of Low-Frequency Electromagnetic Radiation’s Shielding Effectiveness
Authors: Kanafyev O. D. , Trukhanov A. V. , Zubar T. I. , Chizhik S. A. , Grabchikov S. S.
Published: March 2021

Optimization of the radiation coil of the hardware-software complex for studying the effectiveness of shielding of low-frequency electromagnetic radiation will make it possible to assess the effectiveness of shielding coatings at a higher level. This fact will make it possible to develop coatings with improved characteristics. The purpose of this work was to determine the optimal characteristics of the emitting coil which will ensure its stable operation and magnetic field strength in the frequency range up to 100 kHz.

The parameters of the manufactured samples, such as inductance (L), active (R) and total resistance (Z), were obtained using an MNIPI E7-20 emittance meter. In practice, the coils with the optimal parameters calculated theoretically were connected to a current source and amplifier. To detect electromagnetic radiation, a multilayer inductor connected to a UTB-TREND 722-050-5 oscilloscope was used as a signal receiver.

The results of measurements showed that the resistance of multilayer coils is approximately 1000 times higher than that of single-layer coils. Also, for multilayer coils, an avalanche-like increase in total resistance is observed starting from a frequency of 10 kHz, while for single-layer coils there is a uniform increase in total resistance over the entire frequency range up to 100 kHz.

The paper presents results of research on the correlation of the performance of single-layer and multilayer inductors depending on their parameters in the frequency range from  20 Hz  to  100 kHz. Values of the voltage required to provide the magnetic field strength of 1, 5, 20 Oe at 25 Hz and 100 kHz have been calculated. After analyzing the data obtained, the optimal parameters of the inductor were found which ensure stable performance in the frequency range up to 100 kHz.
Development of Executive Equipment Design for Implementing the Process of Generating of Drops of Microand Nanoscale Range
Authors: Kuznetsov M. A. , Ilyaschenko D. P. , Kryukov A. V. , Solodsky S. A. , Lavrova E. V. , Verkhoturova E. V.
Published: March 2021

Modeling of velocities and temperatures processes distribution in the plasma-forming channel determining the design features and optimal parameters of the plasma torch nozzle is one of promising directions in development of plasma technologies. The aim of this work was to simulate the processes of velocities and temperature distribution in the plasma-forming channel and to determine the design features and optimal geometric parameters of the plasmatron nozzle  which  ensures  the  formation  of  necessary  direction  of  plasma  flows for generation of surface waves on the surface of a liquid metal droplet under the influence of the investigated instabilities.

One of the main tasks is to consider the process of plasma jet formation and the flow of electric arc plasma. For obtaining small-sized particles one of the main parameters is the plasma flow  velocity.  It  is necessary that the plasma outflow velocity be close to supersonic. An increase of  the  supersonic  speed  is possible due to design of the plasmatron nozzle especially the design feature and dimensions of the gas channel in which the plasma is formed. Also the modeling took into account dimensions of the plasma torch nozzle, i. e. the device should provide a supersonic plasma flow with the smallest possible geometric dimensions.

As a result models of velocities and temperatures distribution in the plasma-forming channel at the minimum and maximum diameters of the channel were obtained. The design features and optimal geometric parameters of the plasmatron have been determined: the inlet diameter is 3 mm, the outlet diameter is 2 mm.

The design of the executive equipment has been developed and designed which implements the investigated process of generating droplets of the micro- and nanoscale range. A plasmatron nozzle was manufactured which forms the necessary directions of plasma flows for the formation of surface waves on the metal droplet surface under the influence of instabilities. An algorithm has been developed for controlling of executive equipment that implements the process of generating drops of micro- and nanoscale range.
Algorithm for Control of Unmanned Aerial Vehicles in the Process of Visual Tracking of Objects with a Variable Movement’s Trajectory
Authors: Adnastarontsau A. A. , Adnastarontsava D. A. , Fiodortsev R. V. , Katser D. V. , Liavonau A. Y. , Romanov D. V. , Tcherniakovski D. N. , Mikhailau A. О.
Published: March 2021

The purpose of the research was to create an algorithm for determining and correcting the output parameters of the navigation module and the flight-navigation complex of unmanned aerial vehicles which provides control of an aviation gyro-stabilized platform with a multispectral optoelectronic system during flight and tracking various objects of observation.

Principles of control of an aviation technical vision system located on an unmanned aerial vehicle on a two-degree gyro-stabilized platform with the possibility of full turn around two perpendicular axes along the course and pitch are considered. Stability of tracking of observation objects at a distance of up to 10000 m is ensured by the use of a multispectral optoelectronic system including a rangefinder, thermal imaging and two visual channels.

Analysis of the object of observation and the method of its support are carried out. An algorithm is proposed for integrating a Global Navigation Satellite System and a strapdown inertial navigation system based on the extended Kalman filter which includes two stages of calculations, extrapolation (prediction) and correction. Specialized software in theFreeRTOSv9.0 environment has been developed to obtain a navigation solution: latitude, longitude and altitude of the unmanned aerial vehicle in theWGS-84 coordinate system, as well as the pitch, heading and roll angles; north, east and vertical components of velocities in the navigation coordinate system; longitudinal, vertical and transverse components of free accelerations and angular velocities in the associated coordinate system based on data from the receiving and measuring module of the Global Navigation Satellite System and data from the 6-axis MEMS sensorSTIM300.
Evaluation of Nonuniformity of Elastic Properties of Sheets Made from Closed-Сell Polyolefin Foams by Acoustic Method
Authors: Bogdan O. P. , Zlobin D. V. , Murav'eva O. V. , Molin S. M. , Platunov A. V.
Published: March 2021

The widespread use of polyolefin foams in strategically important industries is due to their high thermal, sound and vibration insulation properties. The aim of the work was to evaluate the non-uniformity of elastic properties over the area of sheets of polyolefin foams of various types using the acoustic non-contact shadow amplitude method of testing and confirmation by the structural analysis method.

The article presents the developed installation and a new method of non-contact acoustic testing of sheets made of closed-cell polyolefin foams based on recording the amplitude of the pulse that passed through the sheet and allowing to assess to the unevenness of its elastic properties during scanning. Studies of uneven elastic properties were carried out on sheets of closed-cell polyolefin foams of the ISOLON 500 and ISOLON 300 brands which differ in material and manufacturing technology (technique of cross-linking, method and multiplicity of foaming).

It is shown that the absolute amplitude of the signal and its spread relative to the average value is affected by the structure of the foam polyolefin material and its heterogeneity over the area of the studied sheet determined by the production technology which is confirmed visually using microscopy.

Studies have shown the effect on the indications unevenness of the method of obtaining and the apparent density of the material. It is shown that the most uneven elastic properties and structure belong to sheets of polyolefin foam obtained by chemical cross-linking technology (the unevenness of Δ was 6.5 %). Among the physically cross-linked sheets of polyolefin foam the most uniform in structure and elastic properties are samples made of ethylene vinyl acetate with Δ = 3.8 %, as well as sheets with a high foaming rate (Δ = 3.9 %). The unevenness of structure of the studied sheets of polyolefin foams was confirmed by optical microscopy of sections in two mutually perpendicular directions.
Development and Testing of a Methodology for Assessing of the Correlation Velocity Measurements’ Accuracy for the Hydrodynamic Investigations of the Turbulent Coolant Flow in Nuclear Reactor Elements
Authors: Konovalov I. A. , Chesnokov A. A. , Barinov A. A. , Dmitriev S. M. , Khrobostov A. E. , Legchanov M. A. , Borodin S. S. , Makarov M. A.
Published: March 2021

The correlation method of the coolant flow measuring is widely used in research practice including for studying of turbulent coolant flows in scale models of elements of nuclear power plants. The aim of this work was to develop a technique for assessing the effect of noise recorded by a measuring system on the flow rate readings obtained using the correlation method.

A technique to assess the effect of noise as well as the relative position and acquisition period of sensors is presented. An insignificant concentration of a salt solution (NaCl or Na2SO4 ) is used as a passive impurity which creates a conductivity gradient of the medium recorded by a conductometric system. Turbulent pulsations at the interface between two concurrent isokinetic flows in a channel with a square cross section are used as the signal source for the correlational algorithm.

Paper presents the values of  the  turbulence′s  transport  time  between  spatial  conductometers, the results of estimating the spectral power density and band of the recorded signal and also the signalto-noise ratios of the measuring system obtained on their basis which are subsequently used to estimate the confidence interval of the transport time.

As a result of measurements the relationship between the confidence  interval  value  and  the signal length were obtained. The measurements which were carried out at different relative positions of conductometers make it  possible  to  make  a  conclusion  about  an  increase  in  the  spectral  width of the signal and, as a consequence, a decrease in the length of the confidence interval with increasing of distance between sensors.

The presented work is an approbation of this approach for its application as part of an experimental model of a nuclear reactor in order to determine per-channel flow rates in the channels of the core simulator using mesh conductometric sensors taking into account the effect of noise.
Experimental Installation for Determination of Attenuation Coefficient of Permanent Magnetic Field by Protective Materials
Authors: Fedosyuk V. M.
Published: March 2021

The permanent magnetic field in addition to electromagnetic radiation has a significant effect on performance of devices. This is particularly true for highly sensitive precision measuring equipment, such as, for example, magnetometers or photomultiplier tubes. In this regard a new high-performance materials for protection against permanent fields and electromagnetic radiation need to be developed. The purpose of this paper is a development of a hardware and software complex for high-precision determination of permanent magnetic field attenuation coefficient and certification of protective materials.

This paper describes an experimental installation for determining the attenuation coefficient of a permanent magnetic field using materials and coatings on standard package for electronic equipment. The installation ensures a uniform magnetic field flow in the measurement volume. The advantage of the measuring device is the ability to measure magnetic field in three coordinates due to the use of three pairs of Helmholtz coils and a three-dimensional Hall sensor. The software will enable to control of the magnetic field in all three directions, simulating the real operating conditions of devices that require protection from such influences. In addition, a movable positioning system makes it possible to compensate for the Earth's magnetic field, which increases the accuracy of estimating the attenuation coefficient by protective materials in weak magnetic field.

An alternative use of the capabilities of the installation is to test the performance of the devices in a permanent magnetic field and evaluate the electromagnetic compatibility. Experimental results of the work includes determination of the magnetic field attenuation coefficient using standard photomultiplier tube package made of electrolytically deposited permalloy and the sheet of annealed permalloy. Thus, the effect of annealing and closed magnetic circuit on the degree of weakening of the magnetic field is shown. It has been demonstrated that annealing which causes a significant increase in the magnetic permeability promotes an effective attenuation of weak magnetic fields (up to 1 mT). In magnetic fields with an induction of 1 mT or more, effective attenuation is provided by a closed magnetic circuit.