The paper presents the results of research on morphology, elemental composition, microhardness, corrosion properties of the surface layer of TiNi alloy subjected to ion-plasma (vacuum-arc method) deposition of TiN coating and ultrasonic treatment (UT) with different number of passes (n). The SEM method showed that ultrasonic treatment provides a significant reduction in the amount of the droplet phase on the TiN coating surface. The surface discontinuity of TiN coating at local points was observed with an increase in the number of passes during ultrasonic treatment. The effect of combined processing methods on the microhardness of TiNi sample was studied. It was shown that the synergistic effect can be observed for two hardening methods. The combined strengthening method increased the microhardness of TiNi alloy (1.6 GPa in the as-received state): due to the deposition of a TiN coating – up to 10.9 GPa, due to subsequently ultrasonic treatment – up to 14.5–18.4 GPa depending on the number of passes. For UT + TiN scheme, it was shown that the open circuit potential E_corr was about –250 mV which is practically independent of the number of passes and determined by the potential value of TiN coating. For TiN + UT scheme, it was found that with an increase in the number of passes, the value of E_corr shifts towards more negative values approaching the open circuit potential value of the TiNi sample in the as-received state (–350 mV). The analysis of Scanning Vibrating Electrode Technique (SVET) results showed high electrochemical compatibility of substrate (TiNi) and coating (TiN) materials in a chloride environment with minimal current density fluctuations for the samples subjected to UT + TiN and TiN + UT (n = 1). The proposed method for TiNi alloy treatment according to TiN + UT scheme (n = 1) promotes an improvement of surface morphology and corrosion resistance.

A brief review and critical evaluation of the literature related to the mechanism of carbothermic reduction of silicon oxide is presented. To resolve the contradictions in the literature data about the number of chemical reactions and key intermediate substances during the Acheson process, thermodynamic modeling of products of carbothermic reduction of silicon (IV) oxide at 1 bar total pressure was carried out. It was determined that CO₂ and Si were absent among the intermediates at temperatures close to the silicon carbide formation temperature (from 1520 to ~2500 °С). Out of several dozen possible reactions, the two dominant reactions that result in the formation of silicon carbide in the Acheson process were identified. The effect of reagents temperature from 1000 to 3000 °С, bulk and local deviation from stoichiometry of the initial mixture on the composition of the reaction products was discovered. Obtained new data explains some empirical observations and greatly simplifies the physicochemical modeling of the Acheson process.

The paper considers the problem of the impact of low-frequency electromagnetic fields (EMF) generated by electric vehicles (EV) and household appliances on humans in modern society. The data on the effect of EMF on human health and regulatory documents establishing requirements for electromagnetic safety are presented. The method of electromagnetic shielding and materials for the implementation of this method are considered as a promising method for solving the problem. The levels of electromagnetic radiation from a number of EV and household electrical appliances have been experimentally measured. The efficiency of electromagnetic shielding of materials based on single-layer coatings of Ni₈₀Fe₂₀ alloys, multilayer film structures Ni₈₀Fe₂₀/Cu and amorphous metal alloys AMAG172 has been estimated using a computational method. It is shown that electromagnetic screens based on these materials significantly reduce the levels of exposure to EMF of EV and household electrical appliances on humans, which allows us to approach the hygienic standards recommended by doctors and meet the requirements of regulatory documents on remote control.

The article is devoted to the development of algorithms for calculating the target angle in the coordinate system of an onboard radar and modeling their operation. To construct an algorithm for calculating the target angle, a fixed terrestrial coordinate system and a moving coordinate system of an onboard radar are used. Expressions are presented for recalculating the Cartesian coordinates of an object from the earth coordinate system to the on-board radar coordinate system. The concept of azimuth and elevation planes is introduced for the coordinate system of an onboard radar. Algorithms for calculating target angles in the azimuthal and elevation planes are presented. It is shown that the algorithm for calculating the target angle in the elevation plane has a different form depending on the sign of the target elevation angle. In addition, the type of the mentioned algorithm depends on whether the target is approaching or moving away from the onboard radar. The resulting algorithms for calculating the target angle use information about the coordinates of the target speed in the coordinate system of the onboard radar. Since the coordinates of the velocity vector in the onboard radar cannot be measured, they are estimated from two contacts with the target during the review period. Modeling of the developed algorithms has been carried out.

The results of a study of the influence of the length and number of heat pipes included in the radiator construction on the efficiency of removing excess thermal energy from modern processors are presented. Research was carried out for radiator constructions consisting of a heat sink, a heat pipe and a finned radiator installed on the processor and located in an open environment (air movement occurs without mixing, which is typical for free convection) or in a closed environment (air flows circulate in a closed loop, which is typical for natural convection in a limited space). Numerical modeling was carried out using the Flow Simulation module of the SolidWorks software package. It has been shown that the value of the temperature difference formed at the ends of heat pipes (hereinafter referred to as HP) significantly depends on the natural movement of air flows in an open or closed environment. It has been established that with an increase in the length of the HP from 100 mm to 500 mm, the temperature difference increases both in the case of air flow in an open environment and in a closed environment, in particular, the temperature difference increase at the ends of one HP with a diameter of 6 mm at power 50 W processor will be 29.54 °C (open environment) and 47.14 °C (closed environment); for three HPs – 9.13 °С (open environment) and 16.28 °С (closed environment); for five HPs – 5.24 °С (open environment) and 10.11 °С (closed environment). It has been established that an increase in the number of HPs with a diameter of 6 mm and a length of 500 mm from 1 pc. up to 5 pcs. leads to a decrease in temperature difference, in particular, with a processor power of 50 W, the temperature difference will be 36.17 °C (one HP in an open environment) and 55.59 °C (one HP in a closed environment); 11.04 °С (three HPs in an open environment) and 19.06 °С (three HPs in a closed environment); as well as 6.3 °С (five HPs in an open environment) and 11.56 °С (five HPs in a closed environment). The results obtained can be used to modernize the cooling systems of various technical devices based on processors, as well as to design new high-performance equipment taking into account the use of heat pipes.

The results of a computational analysis of possible modes of combustion of a hydrogen-air mixture in containment during the evolution of a severe beyond design basis accident (BDBA) with the COCOSYS code are presented. The containment of the NPP with a VVER-1200/V-491 reactor was selected as the object of study. BDBA with loss of coolant occurs due to a break of the injection pipeline of the pressurizer system (LOCA DN179) and the simultaneous failure of all active channels of the emergency core cooling system (ECCS). The calculated parameters of the thermodynamic state (pressure and temperature) of the gas mixture are given, and the values of the concentration distribution of hydrogen inside the containment are presented. After calculating the hydrogen distribution and mixing in all compartments of the containment, an evaluation was made of the flammability of the mixture and the potential for self-ignition in the containment by using a three-component Shapiro-Moffette diagram. It was concluded that in BDBA (LOCA DN179 with failure of active ECCS) detonation of the hydrogen-containing mixture is excluded, and deflagration is possible only in the emergency compartment of steam generators with a pipeline break. Thus, the hydrogen risk mitigation has been achieved in accordance with the standards established by the Belarusian regulator, provided that the localization safety systems are operational in the event of hydrogen deflagration. And the efficiency of the hydrogen removal system from the containment using catalytic recombination is considered sufficient for the considered BDBA.

In order to clarify the scheme of radioactive waste management, the accumulation of undesirable beta-emitting radionuclides (PH) in the production of radiopharmaceuticals based on ¹⁸F using the IBA CYCLONE 18/9 HC cyclotron was investigated. It is shown that the dominant impurity PH is tritium, which is formed by the reaction of ¹⁸O(p, t) ¹⁶O when water is irradiated with [¹⁸O]H₂O protons. The main proportion of ³H (about 95%) remains in the regenerated water. 1.6 % of the accumulated tritium activity is carried away from the synthesis zone with gases and water vapor. Tritium-containing waste (regenerated water in vials) can be considered as waste of a very low level of activity during disposal. With an increase in the operating time of the target over 2500 µA · h, the processes of corrosion /erosion of target materials increase, which leads to a sharp increase in the concentration of undesirable radionuclides in regenerated water, sorption purification cartridges and the finished dosage form. The concentration of tritium does not increase significantly. In the β-spectra of regenerated water [¹⁸O]H₂O and the finished radiopharmaceutical [¹⁸F]NaF, in addition to the maximum due to tritium, a number of maxima appear in both the low- and high-energy parts of the spectrum. Other undesirable β-emitters accumulate in water as a result of leaching of the activated target wall. The possibility of using measurements of tritium activity in water [¹⁸O]H₂O as an indicator of its re-enrichment has been demonstrated. The necessity of controlling the content of impurity beta-emitting PH in intermediate products, production waste and final radiopharmaceutical is shown.