The article is devoted to the study of the resistance of structural materials of the BN-350 reactor to pitting corrosion in an aqueous medium containing chlorine ions in the presence of organic corrosion inhibitors. The results of accelerated testing of samples of austenitic steels 12Cr18Ni10Ti, 08Cr16Ni11Mo3Ti and Cr13Mo2NbVB (EP-450) ferrite-martensitic steel for pitting corrosion in a 10% aqueous solution of iron three-chloride hexahydrate without an inhibitor and in the presence of various concentrations of corrosion inhibitor are presented. The effect of heat treatment on the pitting resistance of structural steels is studied and the role of carbide precipitates of MC and M₂₃C₆ types in pitting defects formation is discussed.

This article analyzes the content of heavy metals in the snow cover of the industrial areas of the city of Pavlodar, which made it possible to identify the presence of the problem of environmental pollution. Data on the content of various elements in snow by hazard class were analyzed: in the first hazard class, Zn has the highest content, on average 187.5                mg/kg, the greatest variation in the content of elements is observed in Cd – the coefficient of variation is 118.5%, a high concentration coefficient for Pb and Zn; in the second class – Cr has the highest content, on average 259.1 mg/kg, the greatest variation is observed in Cu – the coefficient of variation is 92%, the concentration coefficient is high in Cr; in the third class – Ba has the highest content, on average 777.5 mg/kg, the coefficient of variation and concentration of Mn. Studies have shown that the content of heavy metals in the snow increases in the northeast direction from the industrial enterprises of the eastern industrial zone of Pavlodar. According to calculations, the content of all heavy metals of the first hazard class in the snow exceeds the maximum permissible concentration (MPC) of soils. The content of cadmium exceeds the maximum permissible concentration by more than 17 times. Heavy metals of the second hazard class are in the range of 0.4–3.2 times the MPC. Strontium exceeds MPC by 25 times. The analysis carried out is an important step in understanding the ecological situation in Pavlodar and can be useful for taking measures to protect the environment and improve the ecological situation in this area.

A team of authors conducted a study of the states and radiation damage of aluminum alloy SAV-1 before and after neutron irradiation with doses of 1016–1020 n/cm2. The measurements were carried out by volumetric methods (small-angle neutron scattering and neutron diffraction) in order to analyze the correlation of the structural state with the results of sample strength measurements obtained using a loading machine. The regularities depending on the fluence of fast neutrons of the strength parameters are revealed, and the regularities of the interdependence of the strength parameters are determined.

The paper presents the results of studying the effect of doping with magnesium oxide (MgO) of lithium-containing ceramics based on lithium metazirconate (Li₂ZrO₃) on the change in the thermophysical parameters of ceramics. The method of mechanochemical synthesis followed by high-temperature annealing at a temperature of 1300 °C, used to initiate the processes of phase transformations from structural ordering, was chosen as the main method for obtaining ceramics, as well as for performing MgO doping processes. In the course of the studies, it was found that an increase in the concentration of the MgO dopant above 0.10 mol leads to the formation of impurity inclusions in the structure of ceramics in the form of a tetragonal phase MgLi₂ZrO₄, the content of which increases with an increase in the concentration of the dopant. In the case of a dopant concentration of 0.25 mol, the phase composition of ceramics is an equiprobable distribution of two phases, monoclinic Li₂ZrO₃ and tetragonal MgLi₂ZrO₄. In the course of measuring thermophysical parameters, it was found that the formation of the MgLi₂ZrO₄ phase in the composition of ceramics leads to an increase in the thermal conductivity by 5–10%, and in the case of an equiprobable distribution of phases in two-phase MgLi₂ZrO₄– Li₂ZrO₃ ceramics, the increase in thermal conductivity is more than 25% in comparison with undoped ceramics. An increase in the efficiency of heat-conducting properties for two-phase ceramics is due to an increase in the rate of phonon heat transfer due to additional interfacial boundaries, as well as an increase in the degree of structural ordering and density of ceramics.

The article presents the results of approbation of the complex method of three-dimensional characterization of radioactive contamination, which allows to build maps with the fields of radioactive contamination of areas and objects in real time. The proposed γ-spectrometric method is optimized for the conditions of necessity to carry out prompt primary assessment of radiation situation at NFC enterprises and consists in carrying out γ-spectrometric measurements using horizontal and angular collimating protection for the detector. Measurements in this case are a successive set of γ spectra in the control measuring points that form a network of radiation survey of the facility.

In this work, the optical characteristics of an aluminum-magnesium spinel irradiated with 220 MeV Xe ions, which simulate the effect of nuclear fuel fission fragments were studied. During the experiments, the transmission spectra were measured in the IR region (240–12500) cm⁻¹, the optical absorption spectra in the range (2–7) eV, the Raman spectra were measured by the ion penetration depth, from the surface to 30 µm. In the optical absorption spectrum (2–8) eV of irradiated spinel crystals, a wide complex band of radiation-induced absorption is observed with a peak in the region of 5.3 eV associated with electronic color centers of the F + and F type, and hole color centers are responsible for optical absorption at ~ (3–4) eV. In the near IR region, the crystal retains its transparency. In the Raman spectrum, in addition to the Raman modes characteristic of an ideal crystal, additional modes, A_1g* (720 cm⁻¹), and E_g* (385 cm⁻¹), appear mainly in the form of an asymmetric shoulder of the main Eg mode. As the depth increases, the A_1g*/Eg ratio increases, reaching a maximum value of 0.05 at 6 µm, and remains practically unchanged until the end of the Xe ion range of 14 µm, and with a further decrease to 0.045 at a depth of 30 µm. That is, when irradiated with 220 MeV Xe ions, cation mixing occurs along the ion path.

Modern territories of the Semipalatinsk Test Site (STS) are not sufficiently involved in economic activities due to environmental conditions and lack of appropriate infrastructure on them. However, sooner or later they can be used, for example, for development of available mineral and building resources on these territories. Since in these lands the geological environment contains many nuclear cavities that significantly affect the mechanical stability of the surface layers, special studies are required in order to assess the subsurface for their carrying capacity for various infrastructure and economic facilities.

This paper presents data on assessing the compliance of the Balapan site boundaries with regard to the development of environmentally significant post-explosive processes. The boundaries of the site, which contain only territories posing direct ecological threat to economic activity, are proposed.

In the work, a conjugate thermo-strength analysis was carried out for the ID-7 experimental device (ED) model. The calculation was carried out using bundles of Ansys Fluent and Static Structural programs in the Ansys Workbench environment using the Fluid-Structure-Interaction (FSI) method. The calculation of the thermal state of the ED was carried out taking into account the results of neutron-physical calculations, using the user function UDF (User Defined Function) of the Ansys Fluent program. According to the results of the non-stationary calculation, the temperature values are obtained, which vary in time and in the height of the ED. Based on the results of the thermophysical calculation, a strength calculation was carried out in the Static Structure program. Distributions of the magnitude of thermal expansion and mechanical expansion (von-Mises) in the elements of the ED are obtained.

An important technological solution for plastic pollution is the replacement of traditional biodegradable polymers, biodegradable polymer materials with physico-mechanical properties that cause environmental pollution. An urgent problem is the search for ways to reduce the self-decomposition of biopolymers and waste, as well as to reduce the cost of such materials, including the use for these purposes of substances that can be analogues of biodegradable polymers. The research work is aimed at obtaining a biodegradable biopolymer based on starch raw materials in the presence of various organic acids (citric acid, acetic acid, lactic acid) and plasticizers (glycerin, polyvinyl alcohol, nanomaterial). An effective material was selected from the products obtained from various acids and plasticizers. Measures to improve the technology of bioplastics production are considered. A durable and economical biopolymer capable of processing and biodegrading biological waste, including starch-containing garbage, has been obtained. The resulting products have successfully passed all physico-chemical tests and are ready for mass production. A scanning electron microscope and thermogravimetric analysis with IR spectroscopy were used to study the physicochemical parameters of the obtained biopolymers.

In this work, the influence of process control agents on the morphology and structural-phase state of powder mixtures of the Ti-Al-Nb system was studied. To improve the technique for grinding powder mixtures of the Ti-Al-Nb system in a planetary ball mill, two types of powders were prepared with the addition of process control agents based on stearic acid and liquid toluene. The process of grinding the compositions with the addition of agents was carried out at 550 rpm/m for 30, 60, 120, 180 minutes.

During the studies, it was found that the evolution of particle morphologies using stearic acid and liquid toluene was similar. The effect of the agent as a process regulator of stearic acid on the evolution of powder morphology was greater than that of liquid toluene, since it inhibited the cold welding process of powders more effectively. During high-energy grinding using toluene for 120 and 180 minutes, undesirable carbide phases are formed.

This paper presents the results of the study of neutron-physical characteristics of an irradiation capsule designed for radiation coloring of topazes. The studies were performed in the core of the critical facility. Sandwich screen made of boron carbide powder and tantalum foil was used to cut off thermal neutrons inside the capsule. It is shown that using sandwich screen the thermal neutron flux is reduced by 8 times, and the fast neutron flux density is practically unchanged. The activation of the tantalum monitor is reduced by more than a factor of 2. The reactivity effect from loading the irradiation capsule with the screen into the core is minus 0.9% Δk/k.

Activated carbon is often used as a carrier, in the manufacture of catalysts and as a sorbent in medicine and pharmaceuticals, as well as in the purification of natural and waste water from various compounds and the concentration of metal ions in the metallurgical industry. A variety of applications for activated carbon causes different requirements for it. The sorption, structural and textural characteristics predetermine the main properties of activated carbon. Improvement of any characteristics of activated carbons, in order to create materials with the required performance properties, is carried out by surface modification with various agents. In this work, liquid-phase oxidation of commercial activated carbon of the brand “BAU-A” with hydrochloric acid was carried out to improve its surface structure and morphology. The IR spectroscopy established oxygen-containing hydroxyl and phenolic, as well as carboxylic, lactone and quinone groups after modification with hydrochloric acid. This in turn affected the morphology of the coal material, which became relatively organized and distinct. Pore volumes after modification with hydrochloric acid decreased to 4.264–5.778 µm, macrocell sizes correspond to 31.57–73.32 µm. XRD analysis has established a decrease in the intensity of areas 2θ – 29° and 43° after modification, indicating the removal of certain minerals with a specific crystal structure, such as Na, Ca and Mg.

In this article, the methods of colloidal chemistry show the ways of using accumulated sulfur in oil production and the possibility of structuring a mixture of sulfur with gypsum in the presence of surfactants and polymer complexes. Compositions consisting of anionic polyelectrolyte (NaKMC) and cationic (CTAB), cationic polyelectrolyte (PDMDAAH) and anionic sulfanol surfactant were prepared, their effect on the surface tension of water, ζ-potential and the effect of polymer and surfactant on sulfur were studied. It was found that with an increase in the relative concentration of the polymer-surfactant composition, the plastic strength of the suspension increases, and after a certain time the strength decreases. This is explained by the fact that when the polar part of the surfactant is added to the polar part of the polymer, the polymer becomes hydrophobic, is better adsorbed on sulfur particles, and the strength of the entire system increases. And when all the polar parts of the polymer are neutralized by the polar parts of the surfactant, the surfactant molecules begin to adsorb on the polymer with their hydrophobic part. As a result, the polymer begins to shrink and form a globule. In this case, the plastic strength of the system decreases.

One of the urgent problems of the agricultural industry in Kazakhstan is the low yield of oilseeds, depending on various factors. The primary factor is the vulnerability of sunflower seeds to different phytopathogens and pests. Diseases develop during almost the entire growing season, starting from the moment of seed germination. In order to avoid mass infection, a large number of fungicides are used, which requires additional financial costs and, on the other hand, worsens the ecological state of the environment, also contradicts the principles of organic farming. In this regard, much attention of researchers is attracted by the development of new technologies for pre-sowing treatment of agricultural seeds, which provide: improving the sowing qualities of seeds, stimulating the physiological and biochemical processes of growth also development of seedlings, reducing the consumption of seed material and increasing the resistance of seedlings to pathogenic microorganisms. Encapsulation or drageeing of seeds solves the problem of their morbidity and death under adverse soil-climatic also extreme conditions of cultivation. Of particular relevance are the tasks of insecticidal and fungicidal activity of encapsulation, the solution of which would increase crop yields by including in its composition the substances necessary for active plant growth (growth regulators, microelements, drugs against fungal diseases). The high cost of the constituent components of polymer shells is noted and, accordingly, the actual problem is to find methods to reduce their cost.

This work is devoted to the selection of the optimal encapsulating composition from gelatin (G) and polyvinyl alcohol (PVA), in a combination of fungicides “Maxim” and “Kruizer” to obtain an encapsulating composition of sunflower seeds.

In this work, the synthesis of orthorhombic SnO₂ nanowires (NWs) was carried out by electrochemical deposition into prepared SiO₂/Si-p ion-track template. Track formations in the SiO₂/Si structure were created by irradiation on a DC-60 cyclotron with swift heavy Xe ions with an energy of 200 MeV (Ф = 10⁸ cm⁻²). A 4% aqueous solution of hydrofluoric acid (HF) was used to form nanoporous templates. Electrochemical deposition (ECD) of SnO₂ into the track template was carried out at room temperature, the voltage at the electrodes was 1.75 V. During the ECD process, an electrolyte with the following chemical composition was used: 6 g/l SnCl₂ (Sigma-Aldrich) – 25 ml H₂O – 2 ml HCl (“reagent grade”; 35%; ρ = 1.1740 g/cm³). The surface morphology of the samples, after the ECD process, was studied on a Zeiss Crossbeam 540 two-beam scanning microscope. The phase composition and crystallographic structure of nanoheterostructures (SnO₂-NP/SiO₂/Si) with nanopores filled with tin dioxide were studied using X-ray diffraction (XRD) on a multifunctional X-ray diffractometer Rigaku SmartLab. Photoluminescence was measured in the optical range of 320–600 nm using a CM2203 spectrofluorimeter (Solar). The electrical characteristics of the synthesized tin dioxide nanowires were studied using a VersaStat 3 potentiostat from Ametek.

As a result, a SnO₂-NWs/SiO₂/Si nanoheterostructure with orthorhombic crystal structure of SnO₂ nanowires was obtained. Photoluminescence excited by light with a wavelength of 240 nm has a low intensity, arising mainly due to defects such as oxygen vacancies and interstitial tin or tin with damaged bonds. Measurement of the current-voltage characteristic showed that the SnO₂-NP/SiO₂/Si nanoheterostructure obtained in this way contains arrays of p-n junctions.

The rapid development of nanotechnology and the intensive use of nanoscale materials in biological and medical applications is the driving factor in the development of new and improvement of existing methods and technologies for the synthesis of nanomaterials. Special attention from researchers is attracted to the green chemistry methods based on the use of highly efficient, inexpensive and non-toxic biological resources for the synthesis of metal nanoparticles and their oxides. Unlike traditional methods of synthesis, green chemistry approaches are not only environmentally friendly but also make it possible to obtain nanoparticles without trace impurities used in the synthesis of precursors and reducing agents. In this work, using endemic plant materials, biogenic composites were synthesized based on silver nanoparticles and vegetative organs of silver birch (inner bark and tinder fungus (birch chaga)) used as biogenic support for the immobilization of nanoparticles. The structure and composition of the samples were comprehensively characterized. The effect of nanoparticles' loading time on the catalytic activity of resulting composites was studied in the model reaction of decomposition of chromium (VI) ions under visible light. The kinetic parameters of the reaction have been studied.

Modeling of thermogravimetric experiments is an essential tool for understanding the physical and chemical processes that occur during research. This approach helps improve data quality and gain a better understanding of what is going on during thermogravimetric analysis.

This paper describes the procedure for modeling a TGA experiment on a Mettler Toledo TGA/DSC 3+ gravimeter, which, together with a mass spectrometer, a humidity generator, and an analytical balance, is part of the TiGRа analytical complex (NNC RK, Kurchatov, Kazakhstan). A description is given of the problem of modeling heat transfer processes in a gravimeter, the process of mass transfer of the reaction gas and reaction products in the gravimeter chamber, as well as the processes of chemical interaction of lithium ceramics with the reaction gas during TGA experiments. Helium with an admixture of oxygen and water vapor was considered as the purge gas.

Calculations carried out using the developed model show that at a purge gas supply rate of 100 ml/s, the temperature gradient across the samples will be 2–2.5 ℃, and the gas velocity in the pebble bed will not exceed 0.5 mm/s. It has been established that the concentrations of CO₂ carried away by the helium flow above the backfill and in the exit zone (in the sampling zone of the mass analyzer) at different temperatures can differ up to 22 times. Thus, using the developed model, it is possible to calculate the concentrations of CO₂, CO, and H₂ at any point of the thermogravimeter furnace directly above the test sample, inside and/or outside the pebble bed, in the area of the reaction mixture inlet and in the sampling area of the mass analyzer, etc. Also, if necessary, it is possible to determine the coefficients for recalculating concentrations in different sections of the pebble bed relative to the measured value. Using this model, it is possible to determine the parameters of chemical reactions – the initial concentration of carbon in the pebble bed, the activation energy of the reactions, and the concentration of O₂ and H₂O impurities in the purge helium, achieving the coincidence of the calculated and recorded curves using a mass analyzer. The developed model has a practical potential for further expansion of its analytical capabilities by refining the list of chemical reactions.

The production of the radiopharmaceutical “Sodium pertechnetate ^99mTc, solution for injection” from the transported ^99mTc generator is a complex multi-stage process that includes the collection and disposal of radioactive waste generated at various technological stages of production, as well as after the return of the generator used in clinics. Currently, natural molybdenum oxide is used for the development of the parent isotope ⁹⁹Mo at the WWR-K reactor, but as the need for ^99mTc generators in Kazakhstan increases, the question arises about the use of expensive molybdenum oxide enriched with the isotope ⁹⁸Mo, therefore, the task of regenerating irradiated molybdenum arises. The paper presents experimental data on the choice of an optimal leaching system for the isolation of molybdenum-98 from spent ⁹⁹Mo/^99mTc generators.

The effectiveness of field observation data processing based on differential phase parameter using the results of spectral measurements of induced polarization using VPF-8k instrument to minimize the inductive noise effects on electric prospecting data using the method of dipole sounding is shown.

The study of the relationship between the effect of phase composition variation on the dielectric characteristics of ferroelectric ceramics is one of the most important fundamental questions, the answer to which will allow us to determine the potential of using ferroelectrics in microelectronic applications and the creation of alternative energy sources (solid oxide fuel cells). The purpose of this study is to explore the effect of the Y₂O₃ dopant on the phase formation processes and the properties of the synthesized ferroelectric ceramics of calcium titanate, as well as to establish the connection between the influence of the formation of impurity phases on the change in the dielectric properties of ceramics. According to the data of X-ray phase analysis, it was found that the addition of Y₂O₃ with a concentration above 0.15 M leads to the formation of an orthorhombic CaY₂O₄ phase in the ceramic structure, the weight contribution of which increases with the dopant concentration growth. An analysis of the dependence of the specific electrical conductivity (σ_DC) with varying dopant concentration showed that the maximum value of σ_DC is achieved at dopant concentrations of 0.05 M, which leads to structural ordering due to the effect of adding yttrium oxide acting as a stabilizer, as well as the formation of impurity donor conductivity in the structure. An analysis of the dependence of the specific electrical conductivity (σ_DC) from dopant concentration was carried out. It has been established that the maximum value of σ_DC is achieved at a dopant concentration of 0.05 M. This is explained by structural ordering due to the addition of a stabilizer –  yttrium oxide, as well as the formation of impurity donor conductivity in the synthesized sample. At the same time, the established dependences of the change in dielectric characteristics are in good agreement with the change in the phase composition, and an increase in the concentration of charge carriers due to the introduction of a donor impurity in the form of Y³⁺ leads to the appearance of volume-charge polarization in ceramics.

Detonation spraying is one of the most promising variants of thermal spraying for the deposition of wear-resistant coatings. This study aims to investigate the tribological properties of coatings deposited by the detonation method using WC-12%Co and Al₂O₃ as examples. These are two common coating materials widely used in wear resistant applications. A computerized detonation spraying system CCDS2000 (Computer-Controlled Detonation Spraying) was used for coating deposition. The roughness parameter of the WC-Co coating has a value of Ra = 3.95 μm and that of the Al2O3 coating has a value of Ra = 2.53 μm. To investigate the detonation coatings, the coating materials were characterized and microhardness measurements were carried out. Microhardness for stainless steel 12Х18Н10Т (AISI 321, 321H) – 392.32 Hv; for WC-12Co coating – 1332.3 Hv and Al₂O₃ – 805.50 Hv. By results of researches the greatest resistance to all kinds of wear has coatings WC-12%Co. Al₂O₃ coatings can also be recommended for operation under sliding wear conditions.

The characteristics of the effective dose field and the dose rate of the ionizing radiation formed in the room of the IGR reactor during its operation at a constant power of 100 MW for 40 seconds have been estimated.

The value of the effective dose and its power in the experimental device has been determined in order to assess the level of the potential radiation load on the small-sized neutron detectors (fission chambers), which are supposed to be used to measure the local values of the fast neutron flux density during the irradiation of the device in the IGR reactor.

To carry out the calculations, the models of the IGR reactor with an upper ceiling, concrete biological protection and two options for loading the central experimental channel of the reactor have been developed. Photon transfer modeling has been performed using the MCNP5 code and the libraries of ENDF/B-5,6 constants, while the characteristics of fission products, 235U decay processes and the processes of formation of gamma-quantum fields were described using the IAEA and JAEA nuclear data libraries.

The validation of the proposed method for calculating the effective dose has been performed based on the results of the direct measurements of the effective dose in the reactor room. The validation results confirm the correctness of the proposed calculation models and techniques, and, accordingly, the admissibility of their application for assessing the radiation situation in the IGR reactor room.

The obtained results will be used in the selection of the locations of secondary equipment for measuring the parameters of the experimental devices.

In the modern world, one of the most important requirements for the production of structural steel parts in machine building is improved hardness and wear resistance. Electrolyte-plasma chemical-thermal treatment is one of the best solutions for this problem, as the surface of steel is modified while the core of the part remains in a ductile state for resistance to impact loading, and this method is resource-saving due to the saving of energy and material consumption. In the present work the questions of technological possibilities of the method of electrolyte-plasma chemical heat treatment of steels are considered. The research results of other authors have been studied, and the analysis of the influence of technological parameters on the change of structural-phase state and improvement of microhardness at electrolyteplasma chemical heat treatment has been given. Electrolyte-plasma carburizing of 20X steel was carried out at the electrolyte-plasma chemical heat treatment unit. A solution of 10% soda ash (Na₂CO₃), 20% urea (CH₄N₂O) in 70% distilled water was used as an electrolyte. It was found that the cross section of steel after electrolyte-plasma carburizing has a zonal structure, so the modified layer with a thickness of ⁓50 μm consists of α-Fe, α'-Fe, Fe₃C. After electrolyte plasma treatment of 20X steel, the microhardness increased ⁓3.5 times compared to the initial state.

NNC RK Bulletin. 2021; 1(85):40–47

Page 46, in the section “Conclusion” instead of: 
«Работа выполнена в рамках реализации НТП КТМ по теме «Разработка и экспериментальное обоснование инновационных технологий для создания термоядерного реактора»

should read:
«Данные исследования финансировались Министерством энергетики Республики Казахстан в рамках научно-технической программы «Научно-техническое обеспечение экспериментальных исследований на казахстанском материаловедческом токамаке КТМ» (ИРН – BR09158585).»

The original article can be found at https://doi.org/10.52676/1729-7885-2021-1-40-47.

NNC RK Bulletin. 2021; 4(88):10–15

Page 14, at the end of the text prior to the section «REFERENCES»

should be added: 
«This research was funded by the Ministry of Energy of the Republic of Kazakhstan (BR09158585).»

The original article can be found at https://doi.org/10.52676/1729-7885-2021-4-10-15.