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The authors analyze the bibliographic information on ecological developments in Donbass for 2000–2022. With the subject headings of the bibliographic index, they follow the trends in ecotechnologies, scientific research and implementation of environmental protection methods and optimization of industrial region’s environments. They emphasize the value of targeted scientific research as the key source of science popularization and public ecological monitoring. They review research, technological and socially important undertakings that in aggregate contribute to achieve all possible harmonization of human existence in the transformed natural ecosystems. The botanical ecological monitoring of natural environments in Donbass has been the only and unique large-scale continuing experiment of independent expertise of region’s natural ecosystems during the social and political conflict (2014–2022). The research project in Donbass is not only the intellectual property object but also the source of ecological education, in particular, owing to the bibliographic analysis and direct community outreach.

Supersonic jets of metal vapors with carrier gas are promising for producing nanostructured metal films at relatively low source temperatures and high deposition rates. However, the effects of the carrier gas on the jet composition and expansion dynamics, as well as on film properties, remain virtually unexplored. In this work, the free-jet expansion of a mixture of silver vapor with helium in a rarefied regime at an initial temperature of 1373 K is investigated through mass spectrometry and direct-simulation Monte Carlo methods. Introducing the carrier gas into the source is found to result in a transition from a collisionless to a collision-dominated expansion regime and dramatic changes in the Ag jet, which becomes denser, faster, and more forward-directed. The changes are shown to be favorable for the formation of small Ag clusters and film deposition. At a fairly high helium flow, silver Ag2 dimers are observed in the jet, both in the experiment and the simulations, with a mole fraction reaching 0.1%. The terminal velocities of silver atoms and dimers are nearly identical, indicating that the clusters are likely formed due to the condensation of silver vapor in the expanding jet. A high potential of supersonic Ag-He jets for the deposition of nanostructured silver films is demonstrated. The deposited jet Ag2 dimers appear to serve as nucleation centers and, thus, allow for controlling the size of the produced surface nanostructures.

The article describes the process of designing and creating a software environment that allows in automatic mode to create a realistic landscape. A review of existing approaches to landscape generation is carried out, which have a set of disadvantages taken into account when developing a software environment. A diagram of components and main classes is described. The developed subroutine that implements the polygon mesh generation algorithm provides an interface for creating and editing a mesh of hexagons on a plane, used for simplified work with biomes, as well as detailing the boundaries of polygons to give the landscape elements of randomness and, as a result, realism. The process uses the Diamond Square noise generation algorithm. The docking algorithm is designed to reduce the gaps between the heights of different biomes. The erosion algorithm uses particles generated on a height mapto carry soil particles in accordance with physical laws. The user interface of the application and the results of the algorithms are presented.

The article describes the stages of the process of creating a virtual reality simulator using the example of a standard operating procedure for replacing a check valve on a Christmas tree. A brief overview of the Christmas tree arrangement and an analysis of the stages of the check valve replacement are described. A short algorithm has been developed based on 11 out of 16 implemented stages. The choice of hardware platform and software is substantiated. Using the Christmas tree as an example, the processes of creating a three-dimensional model and unfolding textures in the three-dimensional editor 3ds Max, creating color maps, reflection and texture normals in the graphical editor Substance Painter are described. The process of creating a landscape in the Unity3D environment is described. Oculus Integration and VR TK assets were used in the development of the main scripts.

The effect of thermal annealing on the structure and properties of fluoropolymer coatings obtained by hot wire chemical vapor deposition is investigated. The structure of fluoropolymer coatings is analyzed by SEM, XPS, and IR spectroscopy. The wetting property is studied by measuring contact angles. The stability of coatings obtained was determined by their treating with an ultrasonic cleaner.

The release of rolling stock and its components for free circulation on the territory of the Customs Union shall be allowed only upon conformity confirmation with the requirements of Technical Regu lations ТР ТС 001/2011 and ТР ТС 002/2011. For conformity assessment of such critical safety related rolling stock component as axle-box bearings the supporting standard GOST 32769–2014 (or GOST 18572–2014) is used. For traditional and high-speed rolling stock the standard foresees changing of the single run duration in the course of full-scale bench tests of axle-box bearings for determination of certification parameter. The example of the test runs of a high-speed train showed that during the time of such single run (in accordance with the standard) the axle-box bearings fail to reach the maxi- mum values of the certification parameters, which can result in unreliable conformity assessment of the axle-box bearings with the safety requirements. With the purpose to increase the reliability of the assessment of the maximum temperature of the axle-box bearings for traditional and high-speed rolling stock and also to bring the conditions of the bench tests of axle-box bearings to the full-scale operating conditions as possible, we propose to consider in the supporting standard the possibility of upholding the duration of single runs while conducting bench tests unchanged, independent of the design speed of the rolling stock

The article describes the automation process of preparation references on educational and methodical documentation of educational program elaborated by Yugra State University teaching staff. Currently, all teachers fill in the reference manually in accordance with the working program of a discipline and a study plan. In such case there is a high probability of making mistakes, indicating unacceptable literature sources, insufficient number of publications and other shortcomings. The automation process of preparation references on educational and methodical documentation of educational program allows to fill in automatically more dynamic fields for a teacher. To automate the described process, it was decided to develop a web application. The authors provide an overview of analogues. The study of the automation system of IRBIS libraries and databases of the electronic catalog of Yugra State University library was carried out. The description of the technologies and languages used in the elaboration of the web application is given.

The hot wire chemical vapor deposition method was applied for fabrication of hydrophobic fluoropolymer coatings on the surface of tubular heaters. The effect of hydrophobic surfaces (with static co...

The method of hot-wire activated chemical vapor deposition (HW CVD) of fluoropolymer films has been adapted to obtain fluoropolymer coatings on rotating cylindrical surfaces of small radius (below 20 mm). The influence of the substrate rotation speed on the structure of thin fluoropolymer deposit was studied and revealed significant dependence of the coating morphology on the speed of cylindrical surface rotation, which is an additional parameter that can be used to control the structure of fluoropolymer coating during the HW CVD process.

The treatment of the hydrophobic properties of solid surfaces is considered as a passive method to reduce the drag in water flows (Rothstein, 2010) and to potentially affect the flow separation and vortex shedding (Sooraj et al., 2020). The manufacturing of surfaces with micro- and nano-scale roughness allows to extend the hydrophobicity towards superhydrophobicity with the contact angle close to 180°. In such conditions the solid surface is not wetted completely and the air-water interphase partially remains on the surface texture. This results in so-called flow slip effect. Therefore, a local phase transition during the flow cavitation or gas effervescence in near-wall low-pressure regions may additionally affect the slip effect for hydrophobic surfaces. The present work is focused on the comparison between cavitating and noncavitating flows around circular cylinders with lateral sectors with hydrophobic and non-hydrophobic coatings. The experiments are performed in a water tunnel, which consists of a water outgassing and cooling/heating section, honeycomb, contraction section, test section and diffuser. The water flow is driven by an electric pump, providing a bulk velocity up to 10 m/s in the transparent test section with 1 m length and 80×150 mm2 rectangular cross-section. The facility is equipped with an ultrasonic flowmeter, temperature and pressure sensors. Besides, the static pressure inside the water tunnel can be varied by using a special shaft section. The measurements are performed by using high-repetition and low-repetition PIV systems. The former is used for the analysis of large-scale flow dynamics in the wake region, whereas the latter one is used for high-resolution measurements in near-wall regions by using a long-distance microscope. The Reynolds number based on the bulk velocity of the flow, diameter of the cylinders (D = 26 mm) and kinematic viscosity of the water is varied up to 2×105..

Objectives. To assess the value of using different treatment schemes in chronic migraine by comparing clinical results and the economic burdens of disease in real clinical practice. Materials and methods. The study included 66 patients attending the Academician Aleksandr Vein Headache and Autonomic Disorders Clinic: 60 women and six men aged 28–51 years with diagnoses of chronic migraine. The patients were divided into three groups: group 1 (n = 22) consisted of patients who received three months of oral prophylactic therapy with topiramate at doses of up to 100 mg/day; patients of group 2 (n = 20) received 12 sessions of acupuncture with three procedures per week; patients of group 3 (n = 24) received injections of botulinum toxin type A (Botox, BTA) at a dose of 155–195 U. The observation period was three months. Treatment efficacy was assessed using the following methods: clinical-neurological assessment, the Headache Impact Test HIT-6 questionnaire, and a subjective points questionnaire assessment for treatment satisfaction and tolerance. Results. BTA was the most effective of the three treatment methods studied in patients with chronic migraine. As compared with oral prophylactic therapy and acupuncture, BTA produced the fastest and strongest actions on the frequency of headache, promoting regression of chronic migraine and recovery of the episodic nature of headache (the numbers of headache days in group 1, 2, and 3 were 16.1 ± 0.1, 18.0 ± 0.02, and 13.9 ± 0.3, respectively, at one month). BTA also produced significantly faster and more effective recovery of quality of life and was better tolerated (good in 51%, 75%, and 85% in groups 1, 2, and 3, respectively; satisfactory in 35%, 25%, and 15% in groups 1, 2, and 3, respectively; poor in 14% in the oral prophylaxis group). Most patients in the BTA group achieved satisfactory treatment results more quickly. Despite the greater direct costs as compared with topiramate, the direct costs associated with the use of BTA (29931.51 and 32085.87 rubles, respectively, the predicted cost per non-headache day in the BTA group was the lowest, at 652.15 rubles (692.86 and 1017.60 rubles in the oral prophylaxis and acupuncture groups, respectively). Conclusions. The efficacy and cost data obtained here for the different methods of prophylaxis of chronic migraine may help specialists and patients select the most optimal therapeutic approaches.

The synthesis of thin silver films by the gas-jet deposition method is experimentally and theoretically studied. When the metal is deposited onto silicon substrates from a supersonic jet of silver vapor with a helium carrier gas, nanostructured films with a 3−30 nm size of nanostructures are obtained for a 1230−1380 K range of jet source temperatures. The data on Ag–He gas-jet dynamics when it is expanded into vacuum (velocity, temperature, concentration, flux of particles onto a substrate) depending on parameters at the source (vapor temperature, flow rate of a carrier gas) are obtained by the method of direct simulation Monte Carlo. The range of optimal helium flow rates, when the efficiency of a gas-jet source is maximal, is determined. It is established that the presence of a background gas in a deposition chamber at pressure higher than 1 Pa decreases the flow of particles onto a substrate, and a simple way of its evaluation is proposed. Conditions for formation of silver clusters in the jet are determined by using the simulation. It is shown that for experimental deposition regimes there are no clusters in the jet, and the observed silver nanostructures are formed on the substrate surface.

Flat surfaces with different patterns of hydrophobic spots were employed for experimental investigation of boiling heat transfer. In one case, hydrophobic spots were created on a smooth copper surface and on a surface coated with arrays of micrococoons from silicon oxide nanowires by vapor deposition of a fluoropolymer. In the second case, a hydrophobic coating was deposited on heater surfaces with cavity microstructures formed by laser ablation and chemisorption of fluorinated methoxysilane. Water under saturation conditions at atmospheric pressure was used as the working liquid. The temperature of the heating surface was varied from 100 to 125 °C, and the maximum value of the heat flux was 160 W/cm2. Boiling heat transfer on the test biphilic surfaces was significantly (up to 600%) higher than on non-biphilic surfaces. Surface texture, the shape of hydrophobic regions, and the method of their creation tested in this study did not show a significant effect on heat transfer. The boiling heat transfer rate was found to depend on the size of hydrophobic spots, the distance between them, and hence the number of spots. The highest heat transfer efficiency was detected for the surface with the largest number of hydrophobic spots. After long-term experiments (up to 3 years), the heat transfer coefficient on the obtained surfaces remained higher than on the smooth copper surface. Biphilic surfaces with arrays of cavities formed by laser ablation turned out to be the most stable during prolonged contact with boiling water.

In the current forensic work we have encountered a very interesting case of infanticide. The interest of this case lies both in the methods that were used to commit the crime, and in the medical error ^ that was committed when saving a dying child; in particular, this last circumstance prompts us to publish this case, the essence of which is as follows.

The article is devoted to the study of the prospects for the use of media technologies in the professional training of teaching staff. The methodological basis of the study was the main provisions of media education and education informatization. When analyzing the problem, such methods as analysis and synthesis were used, as well as systemic and structural-functional approaches. An analysis of the problem of the use of media technologies in the training of future educators showed that the problem of the use of media technologies is relevant both for society as a whole and for the education sector. However, the preparation of future educators for the use of media technologies in professional activities is not given due attention, the prospects for the use of media technologies in the future professional activities of educators have not been sufficiently studied. The study showed that the use of media technologies by an educator should be carried out both in educational activities, and in research and educational activities. Improving the media culture of students-future educators should be one of the important areas of their professional training. Media culture is an important component of the professionalism of a modern educator, which is reflected in the system of assessment. The information and educational space of a pedagogical university should be saturated with media content, which should be in demand during the entire learning process of students.

The formation of a fluoropolymer coating by chemical deposition has been studied experimentally. It has been found that increasing the flow rate of the precursor gas leads to a decrease in the growth rate of the coating. Deposition conditions were analyzed, and the gas-dynamic parameters of the process were estimated. The estimates are consistent with experimental data.

The paper presents the results of the Hot-Wire Chemical Vapor Deposition of fluoropolymer films from C3F6O precursor gas, activated by NiCr wire catalyst mesh, at varying deposition process parameters. The temperature of activator wire is varied within the range of 580–900 °C, precursor gas pressure is changed within the range of 4–1333 Pa, and the temperature of the substrate is changed from 20 to 400 °C. The different surface structures of fluoropolymer coatings are obtained by changing the deposition parameters. The morphology and composition of the films and the growth rate were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy methods. We have measured contact angle, contact angle hysteresis, and surface free energy of the resulting fluoropolymer coatings. The surface structure of the coatings is shown to have a significant effect on the coating wettability. One of the main results is that the increasing of the activating mesh wire temperature leads to increasing of the contact angle and allows us to obtain superhydrophobic coatings. We have shown that the wettability properties can be regulated by deposition parameters. Experimentally determined optimal values of deposition parameters ensure uniform deposition of the film with superhydrophobic properties.

In this paper, the investigation of pool boiling heat transfer on biphilic micro/nanostructured surfaces is presented. An array of micrococoons from silicon oxide nanowires was synthesized on the surface of a copper heater using the gas-jet electron beam plasma chemical vapor deposition method. The biphilic properties of the surface were achieved by applying fluoropolymer spots by hot wire chemical vapor deposition. Technology of creating biphilic surfaces was developed and boiling curves were obtained for used samples. The advantages of using a biphilic surface to enhance heat transfer were demonstrated in comparison with a smooth surface and a micro-nanostructured surface without local hydrophobic fluoropolymer regions. This technology can be applied to enhance boiling heat transfer.

The present work investigates the application of the plasma of glow discharge to deposit the fluoropolymer coatings. Two series of experiments were carried out in which the influence of pressure and current strength on surface coatings morphology during its surface treatment with glow discharge plasma was investigated. The surface morphology is investigated by a scanning electron microscope (SEM), and the water contact angle (WCA) is measured. The fact that the choice of pressure significantly affects the morphology and properties of the deposited coating is established.

We demonstrate that sectoral coating by a hydrophobic fluoropolymer is an effective method for controlling flow separation and the turbulent wake behind a cylinder in high Reynolds number flows (Re = 2.2 × 105). Time-resolved particle image velocimetry measurements show that the shape of the wake and trajectory of large-scale vortex structures are inclined due to delayed flow separation on one side of the cylinder. Near-wall, high-resolution visualization reveals that this effect is related to micro-bubbles traveling along the coated surface. The properties of the coatings and bubble presence did not deteriorate, even after many hours of continuous facility operation.

We present the results of studying the structure of gold nanoparticles synthesized on the silicon surface by two techniques: pulsed laser ablation and magnetron sputtering. The surface morphology is examined by scanning electron microscopy. The structure of the obtained gold nanoparticles is analyzed by transmission electron microscopy and electron diffraction. It is shown that nanoparticle sizes and crystal structures can be controlled by their thermal annealing. Mechanisms occurring during annealing of thin gold films and also their effect on the formation of nanoparticles with different structures are investigated.

We examine the motions of an autonomous Hamiltonian system with two degrees of freedom in a neighborhood of an equilibrium point at a 1:1 resonance. It is assumed that the matrix of linearized equations of perturbed motion is reduced to diagonal form and the equilibrium is linearly stable. As an illustration, we consider the problem of the motion of a dynamically symmetric rigid body (satellite) relative to its center of mass in a central Newtonian gravitational field on a circular orbit in a neighborhood of cylindrical precession. The abovementioned resonance case takes place for parameter values corresponding to the spherical symmetry of the body, for which the angular velocity of proper rotation has the same value and direction as the angular velocity of orbital motion of the radius vector of the center of mass. For parameter values close to the resonance point, the problem of the existence, bifurcations and orbital stability of periodic rigid body motions arising from a corresponding relative equilibrium of the reduced system is solved and issues concerning the existence of conditionally periodic motions are discussed.

In the article we examine the question on solvability, uniqueness, and some qualitative properties of solutions to inverse problems of recovering point sources (the right-hand sides of a special form) in a one-dimensional parabolic equation. The values of a solution at some collection of points are taken as the overdetermination conditions. Examples are exposed that show that the uniqueness fails without additional conditions on the mutual disposition of sources and measurement points.

The physiological stress modeled by circulatory hypoxia activates LPO processes in various tissues. In posthypoxic period, the infrared low-intensity laser irradiation significantly decreased the chemiluminescence parameters in blood plasma, normalized the retinal levels of diene and triene conjugates, and decreased MDA in the rat brain attesting to the correcting effect of this irradiation during various types of physiological stresses.

To evaluate the rationale for different approaches to preventive chronic migraine (CM) treatment by comparing clinical outcomes and financial burden of the disease in the real-world practice.Sixty-six patients with CM were enrolled at the Alexander Vein Headache Clinic (60 women and 6 men, aged 28-51). All patients were divided into 3 groups: group 1 (n=22) received oral preventative treatment with topiramate, up to 100 mg daily, for three months; group 2 (n=20) received 12 acupuncture sessions (3 sessions a week); group 3 (n=24) received 155-195 units of botulinum toxin type A (botox, BTA). The follow-up period in all groups was 3 months. Efficacy was evaluated by clinical examination, the Headache Impact Test (HIT-6) and questionnaires to assess subjective patient satisfaction and treatment tolerability.BTA demonstrated the highest efficacy in this study. Compared to the oral preventative treatment and acupuncture, BTA reduced the frequency of headache faster and more significantly facilitating CM transformation into episodic migraine (headache frequency was 16.1±0.1; 18.0±0.02; and 13.9±0.3 in groups 1, 2 and 3, respectively, after one month of treatment). BTA also improved the quality of life faster and more significantly and was better tolerated (good - 51%, 75% and 85% in groups 1, 2 and 3, respectively; satisfactory - 35%, 25% and 15% in groups 1, 2 and 3, respectively; bad 14% in the oral prevention group). In the BTA group, the majority of patients demonstrated earlier treatment satisfaction. Despite higher (compared to topiramate) direct costs in the BTA group (RUB 29 931.51 and RUB 32 085.87, respectively), the predicted cost of a headache-free day was the smallest and totaled RUB 652.15 (compared to RUB 692.86 and RUB 1017.60 in the topiramate and acupuncture groups, respectively).The data on the efficacy and costs of different CM prevention strategies would facilitate optimal treatment choice for neurologists and patients.Цель исследования. Оценка целесообразности применения различных схем лечения хронической мигрени путем сопоставления клинических результатов и экономического бремени заболевания в реальной клинической практике. Материал и методы. В исследование были включены 66 пациентов Клиники головной боли и вегетативных расстройств им. академика Александра Вейна: 60 женщин и 6 мужчин в возрасте от 28 лет до 51 года с диагнозом хронической мигрени. Пациенты были разделены на три группы: в 1-й группе (n=22) пациенты принимали трехмесячную пероральную профилактическую терапию топираматом в дозе до 100 мг в сутки; пациентам 2-й группы (n=20) проводили 12 сеансов иглорефлексотерапии по 3 процедуры в неделю; пациенты 3-й группы (n=24) получали инъекцию ботулинического токсина типа А (Ботокс, БТА) в дозе 155-195 ЕД. Период наблюдения за пациентами составил 3 мес. Для оценки эффективности лечения использовали следующие методы: клинико-неврологический, анкета 'Индекс влияния ГБ' (HIT-6), а также анкеты субъективной балльной оценки удовлетворенности терапией и ее переносимости. Результаты. БТА оказался самым эффективным из трех изученных методов лечения пациентов с хронической мигренью. По сравнению с пероральной профилактической терапией и иглорефлексотерапией БТА быстрее и сильнее воздействует на частоту головной боли, способствуя регрессу хронической мигрени и восстановлению эпизодического характера головной боли (через 1 мес число дней головной боли в 1-й, 2-й и 3-й группах составила 16,1±0,1; 18,0±0,02; 13,9±0,3 соответственно). БТА также значимо быстрее и эффективнее восстанавливал качество жизни и лучше переносился (хорошо - 51, 75 и 85% в 1-й, 2-й и 3-й группах соответственно; удовлетворительно - 35, 25 и 15% в 1-й, 2-й и 3-й группах соответственно; плохо - 14% в группе пероральной профилактической терапии). У подавляющего числа больных в группе БТА быстрее достигнута удовлетворенность результатами лечения. Несмотря на большие по сравнению с топираматом прямые затраты, связанные с применением БТА (29 931,51 и 32 085,87 руб. соответственно), прогностическая стоимость дня без головной боли в группе БТА оказалась минимальной и составила 652,15 рублей (692,86 и 1017,60 руб. в группах пероральной профилактической терапии и иглорефлексотерапии соответственно). Заключение. Полученные данные об эффективности и стоимости различных методов профилактики хронической мигрени могут облегчить специалистам и пациентам выбор наиболее оптимального терапевтического подхода.

The surface modification is one of the most promising and discussed methods to improve the boiling performance. To date there are a lot of techniques to modify a heating surface, but the search for the optimal, simple and reliable one is still an actual problem. Recently, the surface texturing using laser ablation was applied in a number of studies, which showed its great potential for heat transfer enhancement and critical heat fluxes increase during pool boiling on the metal surfaces. In this paper, we modified a silicon surface by laser texturing and analyzed its effect on the heat transfer and bubble dynamics during water pool boiling using high-speed thermography and video recording. The experiments showed that the usage of laser-textured surface results in the heat transfer enhancement up to 49.5% compared to the reference rough silicon sample and up to 234% compared to the polished sample. Moreover, the modified surface is characterized with lower onset of nucleate boiling and lower bubble nucleation temperature. Dataset on the major characteristics of bubbles dynamics during boiling on the untreated and laser-textured surfaces was obtained using the high-speed video recording. Its analysis showed that the laser treatment leads to the significant increase in the nucleation site density and nucleation frequency, while the bubble departure diameter value dramatically decreases compared to the reference surface. On the basis of experimental data the relationship between nucleation frequency and departure diameter was found and analyzed both for untreated surface and for laser-textured one.

The membranes were synthesized by deposition of fluoropolymer coatings on metal meshes using the Hot Wire Chemical Vapor Deposition (HW CVD). The obtained membranes were used for the separation of an oil-water emulsion in a simple filtration facility. The main process parameters influencing the separation efficiency were determined and the optimal separation mode was selected. It was shown that the highest efficiency on the obtained membranes is achieved by separating emulsions containing water less 10%.

The hot wire chemical vapor deposition method has been adapted to deposit fluoropolymer coatings on small-radius rotating surfaces. The influence of the rotational frequency of a cylindrical sample during the deposition process on the formation of a layer of fluoropolymer coating was studied. It was found that the rotational frequency of the cylindrical sample significantly changed the morphology of the resulting coating. It was shown that with an increase in the sample’s rotational frequency from 1 to 100 rpm, the deposition rate decreased and the coating structure degraded. To establish the reasons for this effect, a numerical study of the flow around a rotating cylindrical sample was carried out for a range of low gas velocities and densities in the reactor. The simulations are based on solving the Navier–Stokes equation with no slip and velocity slip boundary conditions for a rotating surface. It was found that the main reason for the decrease in the deposition rate was associated with the effect of the formation of a closed circulation flow region above the sample’s surface during rotation. The dependence of the characteristic size of this region on the rotational frequency of the cylinder sample was close to linear. The effects of surface boundary conditions were also analyzed.

Degradation-resistant two-dimensional metal–fluoropolymer composites consisting of gold nanoparticles coated with a thin fluoropolymer film were deposited on a substrate by hot wire chemical vapour deposition (HWCVD) and ion sputtering. The morphology and optical properties of the obtained coatings were determined. The thickness of the thin fluoropolymer film was found to influence the position of the surface plasmon resonance peak. Numerical calculations of the optical properties of the deposited materials were performed using Mie theory and the finite-difference time-domain (FDTD) method. The calculation results are consistent with the experimental data. The study shows that the position of the resonance peak can be controlled by changing the surface concentration of particles and the thickness of the fluoropolymer coating. The protective coating was found to prevent the plasmonic properties of the nanoparticles from changing for several months.

One possible circuit of a power transformer with vector control is considered. Initial statements of the electromagnetic analysis of transformers are given. An algorithm for determining the voltage and current time dependences, as well as characteristics ones, is described. The dependences between the power transformer characteristics with vector control and the control parameters are shown by the example of the transformer with a nominal power of 16 MV A and nominal supply voltage of 110 kV. The conclusion is drawn that minimum power losses are present at a certain combination of control parameters. The time dependences of current and voltage power keys involved in the transformer of active converters, which result from the mathematical simulation in MATLAB and Simulink, are presented. The effectiveness of the proposed model is evaluated.

This paper describes the method of obtaining composite coatings consisting of silver nanoparticles covered by a fluoropolymer film. The morphology and optical properties of resulting coatings are given within. The presence of a surface plasmon resonance (SPR) minimum of silver nanoparticles deposited on glass and fused silica surfaces has been revealed. The paper describes a shift towards the infrared (IR) region when the average size of deposited silver nanoparticles is changed. However, coating the nanoparticles in a fluoropolymer film does not significantly shift their resonance.

Data on the optical properties of a nanocomposite material constituted by gold nanoparticles covered with a thin film of amorphous hydrogenated silicon suboxide have been obtained for the first time. The thin film was deposited by gas-jet electron-beam plasma chemical-vapor deposition. As gold particles situated on the surface of quartz glass are covered with a thin a-SiO x : H film, their plasmonic resonance peak is shifted to longer wavelengths. The calculations made in the study demonstrated a good agreement with the experiment.

The mass thickness of thin metal films is an important parameter determining the film structure, however a robust routine method for its determination is still missing. In this work, we have developed a simple optical method for determining the mass thickness of gold films with arbitrary morphology on transparent substrates in the range 1–20 nm. The method is based on film spectrophotometry in the far-UV range when the light attenuation is due to interaction with core electrons and thus the influence of the film morphology is negligible. The calibration was performed at a wavelength of 200 nm for gold films of known thickness and a good agreement with the Beer–Lambert law was obtained. The feasibility of the method was demonstrated with gold films of various morphologies produced on quartz substrates by pulsed laser deposition.

The evolution of the morphology and composition of the single-crystal silicon surface irradiated by infrared and visible nanosecond laser pulses is investigated as a function of processing parameters (laser fluence, irradiation spot size, the number of pulses, background gas pressure and composition). Two types of periodic surface microstructures are obtained with IR (1064 nm) laser pulses in a narrow fluence range of 3–6 J/cm2. At a relatively low number of laser pulses applied, a grid of cleavage cracks is produced within the irradiation spot along the crystal orientation. With further Si irradiation, periodic microhillocks are formed in the nodes of the crack grid. Silicon surface with such microhillocks exhibits superhydrophilic properties which are retained during prolonged storage in air. The cracks are produced in any environment (including vacuum) but the microhillocks are observed only in the presence of oxygen. No periodic structures were observed with visible (532 nm) laser pulses. Mechanisms of nanosecond laser-induced periodic microstructure formation on silicon are discussed.

The paper presents the results of an experimental study of the effect of hydrophobic fluoropolymer coating on the multiscale characteristics of heat transfer at water boiling. New experimental data on dynamics of vapor bubble growth and detachment, evolution of contact line, nucleation site density, heat transfer coefficient were obtained using high-speed imaging techniques, including infrared thermography and video recording from the bottom side of transparent ITO heater. It was shown, that the using of hydrophobic fluoropolymer coating leads to heat transfer enhancement, to decrease of the superheat temperature at the onset of boiling, to increase of the active nucleation site density and to significant change in the dynamics of growth and departure of vapor bubbles and the evolution of the triple contact line.

Immune aggression to transplanted allogeneic bone marrow, i.e. the graft-versus-host disease (GVHD), could be decreased by the suppression of effector and/or activation of T- regulatory cells (Treg). This task could be solved by co-transplantaiton of allogeneic bone marrow and mesenchymal stromal cells (MSCs). This study demonstrated the elevated immune modulating activity of MSCs by their culturing in vitro on Al₂0₃ oxide nanocoatings. Introduction of the cells to the animals with GVHD resulted in an increased content of Treg in the spleen of bone marrow recipients, reduced severity of the pathology, and higher survival of animals. Thefindings could be the basis for developing the new approaches to optimize the GVHD treatment methods involving the oxide nanocoating cultured MSCs.