Eurasian Physical Technical Journal

ENHANCING THE DURABILITY OF ROBOTIC ARM USING COMPOSITE MATERIALS AND ADDITIVE MANUFACTURING IN HARSH ENVIRONMENTAL CONDITIONS

R. Askaruly, T. Faizulla, M. Abylkanov, A.B. Syzdykov, K. Sakhanov (Author) — Tue, 30 Sep 2025 00:00:00 +0500

Despite the harsh environmental conditions, such as strong winds, radiation exposure and frequent forest fires, pose serious challenges for the reliable operation of robotic systems. Despite growing interest in robotics for disaster relief and hazardous operations, the durability of additively manufactured components under such stresses remains insufficiently explored. This study investigates the use of composite materials and additive manufacturing techniques to improve the performance of robotic manipulators in harsh conditions. A modular rover equipped with a robotic arm made entirely of composite elements was developed and tested. The research focused on evaluating the structural reliability of PETG plastic and carbon fiber in terms of thermal exposure, static load, and radiation resistance. The study also presented a gesture-controlled interface for remote control and produced a functional prototype. The results of the study provide new insights into material selection and design strategies for sustainable robotic systems, contributing to the development of sustainable robotics in harsh environmental conditions.

UNIVERSAL MODULAR ONBOARD CONTROL COMPLEX OBCARM G2 NANO FOR NANO-CLASS SPACECRAFT

Y. Sarsenbayev, K. Ostretsov, K. Baktybekov, A. Mussina, A. Yskak (Author) — Tue, 30 Sep 2025 00:00:00 +0500

Universal modular onboard control system OBCARM G2 NANO has been developed for 3U-12U nano-class spacecraft designed for communications, Earth remote sensing, or the Internet of Things. OBCARM G2 NANO consists of interface and processor modules on separate printed circuit boards. The Zynq Ultra scale+ SoC-based processor mod-ule provides ARM TMS470-based module telemetry control support and necessary peripherals, including 500 MB DDR4 RAM for the CPU, 125 MB RAM for the programmable logic gate array field-programmable gate array 125 MB QSPI Flash for flight software storing, and 128 GB eMMC Flash as ROM. Interface module contains onboard control system modules power lines, interfaces of the control system and payload data transmitter and receiver, as well as drivers that provide con-version and buffering of payload data. The OBCARM G2 NANO uses QNX RTOS for flight software, and a high-performance AXI bus for interaction between the processor system and field-programmable gate array. CAN bus is used to ensure spacecraft subsystems operation in a single network. The dimensions of the OBCARM G2 NANO mechanical equipment, including a set of temperature monitoring sensors and a thermal bridge for removing excess heat from hot spots, are 95 mm x 95 mm x 35 mm.

DEVELOPMENT AND OPTIMIZATION OF OPTICAL PAYLOAD FOR NANOSATELLITES WITH STRICT CONSTRAINTS

Tue, 30 Sep 2025 00:00:00 +0500

This article presents the design and optimization of a compact, high-performance optical payload for Earth observation nanosatellites. The payload is based on a Ritchey-Chrétien telescope with corrective lenses, providing a ground sample distance (GSD) of 6 meters per pixel from a 600 km orbit while meeting strict constraints on mass, dimensions, power consumption, and operational conditions in the space environment. The design process, conducted using Zemax 2024 software, focuses on achieving high image quality within the limitations typical for a 12U CubeSat. The results confirm the feasibility of the project, ensuring a modulation transfer function value exceeding 0.26 at the Nyquist frequency. Several key performance indicators were evaluated, including the system modulation transfer function. Once the required parameters were achieved, a lens corrector system was added and the field angles were optimized. BK7 and Fused Silica were selected as lens materials. The simulation results confirm that the developed optical payload meets the requirements for use in space conditions, including resistance to vibration loads during launch vehicle launch.

A Dynamical System Approach to Language Bias Evolution on Complex Networks

Y.Z. Baibolatov, Y.D. Nalibayev, Y.T. Kozhagulov (Author) — Tue, 30 Sep 2025 00:00:00 +0500

We propose a dynamical systems model to study language competition and bias evolution in structured agent populations. Each agent is characterized by a continuous bias variable representing their linguistic preference, evolving under the combined influence of peer interactions, native language retention, and external prestige forces. The model incorporates a nonlinear damping mechanism that confines the agent's bias within a fixed range between negative one and one, and allows for heterogeneous susceptibility and retention parameters. We analyze the model in its linear regime and perform a stability analysis of the fixed points under both symmetric and asymmetric network topologies. Simulations on fully connected and small-world networks reveal diverse dynamical scenarios, including language death, bilingual persistence, and spontaneous population bifurcation into opposing linguistic groups. The results provide insight into the interplay of social structure, identity, and external influence in shaping language dynamics.

DESIGN ANALYSIS OF A WIEN-BRIDGE OSCILLATOR: FROM PROTOTYPE TO TEMPERATURE PERFORMANCE

Tue, 30 Sep 2025 00:00:00 +0500

A prototype Wien-bridge oscillator was designed and constructed using a single Op-Amp with a diode-bridge included in the degenerative-feedback path to provide amplitude stabilization of the output oscillations. A circuit simulator, PSpice version 10.0P was also used to simulate the circuit. The simulated results were compared with those measured with an oscilloscope for validation, and it had 90% accuracy. The relationships between the operating temperature and the settling time of the oscillator, as well as the resonant frequency, were investigated and derived. The resonant frequency of the constructed oscillator is adjustable between and The prototype circuit in this work that measures this range of frequencies was successfully analyzed, and the investigated effects of temperature variations on the output signals are presented in section 3. The results of the temperature response to the output bias voltage, source currents, and total power dissipation of the circuit are also presented. The overall results of the presented parameters show that the operating temperature of the oscillator (within a temperature limit) has an unpredictable effect on its output, which could adversely affect the performance of the oscillator where precision is of great importance.

ANNEALING-INDUCED MORPHOLOGICAL EVOLUTION OF IRON NANOCATALYSTS FOR CARBON NANOTUBE GROWTH

A.A. Ismatov, C. Romanitan, Kh.B. Ashurov, M.M. Adilov, A.A. Rahimov (Author) — Tue, 30 Sep 2025 00:00:00 +0500

The synthesis of iron nanocatalysts on silicon substrates via the Electron Beam Physical Vapor Deposition method has garnered significant attention due to its catalytic uses. The influence of annealing temperature (500°C, 550°C, and 600°C) on the structural and morphological characteristics of Fe nanocatalysts and their use in the growth of carbon nanotubes via Chemical Vapor Deposition is investigated in this study. Atomic Force Microscopy and Scanning Electron Microscopy measurements reveal that an increase in the annealing temperature reduces the average nanocluster size, and annealing at 600°C yields nanoclusters with an average size of approximately 30 nm; hence, they are more effective as catalysts. Raman spectroscopy proved that carbon nanotube growth was only observed on the 600°C-annealed substrate, and it exhibits a high I_D/I_G ratio (<1), indicating high crystallinity and low defect concentration. The absence of Radial Breathing Mode peaks represents additional evidence that the synthesized carbon nanotubes are multi-walled. These findings indicate that nanocluster size and distribution must be controlled with high accuracy using Electron Beam Physical Vapor Deposition and thermal treatment in order to maximize Fe nanocatalysts for carbon nanotubes growth.

OBTAINING MULTICOMPONENT CHROMIUM COATINGS USING FUNCTIONALLY ACTIVE MIXTURES

D.B. Sereda, I.V. Kruglyak, B.P. Sereda (Author) — Tue, 30 Sep 2025 00:00:00 +0500

The purpose of our research is to obtain wear-resistant chrome coatings on carbon steels under non-stationary temperature conditions using functionally active powder mixtures, which allows reducing the chemical-thermal treatment time from 6-8 hours to 1 hour. The scientific novelty of the work lies in the original use of thermodynamic analysis to determine the composition of the gas phase formed during chemical-thermal treatment with functionally active charges, which made it possible to optimize the concentration of ammonium compounds for boron-alloyed chrome surface and predict its physical and mechanical characteristics. The practical significance of the developed technology is to increase the wear resistance of chrome coatings on steels with a ferrite-pearlite structure, which ensures their effective use under dynamic and impact loads. The proposed method opens up new opportunities for the creation of highly effective protective coatings for industrial applications. Optical microscopy (Neophot-32) and scanning electron microscopy (REM-106i) were used to study the microstructure and phase composition of the coatings. Tribotechnical tests were carried out on friction installations SMT-1 and MT-5. The composition of the gas medium formed during the chemical heat treatment was determined by thermodynamic modeling, and the optimization of the component composition of the charge materials was carried out using the methods of mathematical planning of experiments with the optimization criterion in the form of wear resistance of the boron-alloyed chrome surface. As a result, it was found that the addition of boron-containing components and ammonium gas transport reagents to the powder charge composition contributes to the generation of gaseous compounds and condensed phases. The proposed functionally active mixtures ensure the formation of protective chromium layers up to 150 μm thick within 15-60 minutes.

EVALUATION OF THE APPLICATION EFFICIENCY OF MULTICOMPONENT CERAMICS AS PROTECTIVE SHIELDING AND THERMAL BARRIER MATERIALS

Tue, 30 Sep 2025 00:00:00 +0500

The paper presents the comparative analysis results of the shielding characteristics of multicomponent ceramics obtained by mixing TeO₂, CeO₂, WO₃, ZnO, Bi₂O₃ and ZrO₂ oxides in various molar ratios, enabling acquisition of ceramics with a variable phase composition. According to the results of X-ray phase analysis, the addition of ZrO₂ to the composition of composite ceramics leads to the formation of a monoclinic substitution phase ZrCeO₂. The contribution growth of the latter results in strength properties growth due to a change in the concentration of interphase boundaries in the composition of ceramics. During the tests conducted for resistance to thermal effects capable of leading to destabilization of the crystalline structure, it was established that an increase in the contribution of ZrO₂ in the composition of ceramics leads to an increase in resistance to thermally induced softening processes, and an increase in the stress resistance of ceramics during tests for thermal shock effects. During determination of the shielding characteristics of the studied ceramics, it was found that the formation of a stabilizing ZrCeO₂ phase in the composition of multicomponent ceramics leads to an elevation in the shielding efficiency, as well as the stability of the preservation of shielding characteristics as a result of long-term thermal effects and thermal shock tests. Moreover, the greatest increase in the efficiency of the measured parameters is observed in the case of assessment of thermal insulation characteristics. The increase in the latter is more than 2.5 times compared to non-stabilized ceramics, which do not contain inclusions in the form of the ZrCeO₂ phase.

THERMODYNAMIC AND ELECTROPHYSICAL PROPERTIES OF A NEW SEMICONDUCTOR BASED ON OXIDES OF RARE-EARTH AND TRANSITION METALS

Tue, 30 Sep 2025 00:00:00 +0500

The study focuses on the investigation of a new compound that combines the properties of manganites and zirconates, paving the way for the development of highly efficient functional materials. The compound was synthesized through the interaction of lanthanum oxide, zirconium oxide, manganese oxide, and sodium carbonate at temperatures ranging from 800 to 1200 °C and studied using X-ray analysis methods, including the determination of cubic lattice parameters. The analysis of the temperature dependence of heat capacity revealed second-order phase transitions, based on which equations describing its variations were derived. Thermodynamic characteristics such as entropy and enthalpy were calculated. Electrophysical measurements confirmed the semiconductor nature of the material within a specific temperature range and revealed high values of dielectric permittivity, surpassing those of reference materials.

SYNTHESIS OF SILVER NANOPARTICLES AND THEIR INFLUENCE ON THE FLUORESCENCE AND ABSORPTION OF ANTHRACENE

Zh.B. Yusupova (Author) — Tue, 30 Sep 2025 00:00:00 +0500

The synthesis process of island silver films was investigated, with a focus on the role of solution pH as a key parameter for successful film formation. It was determined that the optimal pH for effective synthesis is 8. The results of particle distribution analysis by Feret diameter, performed using the ImageJ software, are also presented. The distribution histogram confirmed that the chemically deposited film is of high quality. The developed synthesis method enables the fabrication of silver nanoparticle films with tailored properties. The influence of the synthesized silver films on the luminescent properties of anthracene was studied, highlighting their potential applications in photonics and sensor technologies.

SPECTROPHOTOMETRIC STUDIES OF ASTEROIDS II: TAXONOMIC TYPE

G.K. Aimanova, A.V. Serebryanskiy, M.P. Shcherbina, M.A. Krugov (Author) — Tue, 30 Sep 2025 00:00:00 +0500

Analysis of spectral observations of a number of Main Belt asteroids, the Apollo family asteroid (NEO) 30825 (1990 TG1), and the rare asteroid 1951 Lick was used to determine their taxonomic types. The observations were carried out in 2023-2024 at the Assy-Turgen Observatory on the AZT-20 telescope equipped with a spectrograph using a volume-phase holographic dispersive element with 360 lines per millimeter in low-resolution mode (R=600). We use the “template” method proposed in (Savelova A.A. et al., 2022) and the visual albedo values. An analysis was carried out for S-type asteroids (107) Arachne and (482) Petrina and the Apollo family asteroid (NEO) 30825 (1990 TG1), which have minerals formed under high-temperature conditions, as well as asteroid (97) Klotho, belonging to the M class, which includes asteroids with an increased metal content. Class A asteroids are characterized by high albedo and a marked increase in reflectance at longer wavelengths. These features indicate the presence of high-temperature olivine or mixtures of olivine with metals, mainly iron and nickel. The presented results show that asteroids (366) Vincentina and (1951) Lick belong to this class. The analysis showed that the normalized reflectance spectrum of (47) Aglaja corresponds to asteroids of spectral class B, the main components of the surface of which are probably anhydrous silicates, hydrated clay minerals, organic polymers, magnetite, and sulfides. According to the authors' results, the normalized reflectance spectrum of asteroid (718) Erida corresponds to the spectral corridor for the T-class template with an albedo ranging from 0.04 to 0.042.

A NOVEL DESIGN OF AN ENERGY ANALYZER FOR CHARGED PARTICLES BASED ON A NON-UNIFORM ELECTROSTATIC FIELD

Zh.T. Kambarova, A.O. Saulebekov, S.S. Kassymov (Author) — Tue, 30 Sep 2025 00:00:00 +0500

A new design for an energy analyzer based on an axial symmetric non-uniform field has been proposed. Using the superposition method of a cylindrical field and second-type axially dodecapole, the electron-optical scheme for the energy analyzer has been developed. Numerical modeling of the electron-optical scheme of the device was performed, and its analytical characteristics were obtained. It is shown that the proposed design combines high resolution and effective luminosity. The results confirm the feasibility of using the developed device for studying charged particle beams in outer space.

NUMERICAL ANALYSIS AND CHAOS CONTROL: A STUDY OF LORENTZ SYSTEMS WITH VISUAL BASIC FOR APPLICATION IMPLEMENTATION

T. Shugayeva, A. Amantaeva, I. Spivak-Lavrov (Author) — Tue, 30 Sep 2025 00:00:00 +0500

The study focuses on the numerical analysis and chaos control of Lorenz systems, leveraging Visual Basic for Application in Microsoft Excel for modeling and visualization. Chaotic systems, including the Lorenz attractor, represent a fundamental concept in nonlinear dynamics and chaos theory, characterized by sensitivity to initial conditions, nonlinearity, and fractal dimensionality. These properties make such systems valuable for analyzing complex processes in physics, biology, engineering, and economics. The research extends traditional exploration of the Lorenz attractor by introducing numerical methods such as the four-point Adams method with adaptive step selection. Classical parameter sets and non-classical modifications are examined. Additionally, a modified Lorenz system incorporating a supplementary term is analyzed, demonstrating distinct dynamic behaviors and trajectories. This work highlights the applicability of the developed Visual Basic for Application-based tools for solving nonlinear differential equations and visualizing complex attractors. The integration of Adams and Krylov methods enhances computational efficiency and precision. The outcomes align with previous studies and suggest that the software can address a wide range of applied mathematical and engineering challenges, including chaos management in dynamic systems. The findings underline the potential of the Lorenz attractor as a testbed for chaos control methods and numerical analysis techniques, with broader implications for scientific and practical applications across various disciplines.

A STUDY OF HEAT TRANSFER GENERALIZATION FOR A COOLING SYSTEM WITH MINERAL MEDIA COATINGS

A.A. Genbach, D.Yu. Bondartsev (Author) — Tue, 30 Sep 2025 00:00:00 +0500

Studies of heat transfer in cooling systems with natural material coatings have been carried out. The phenomenon of flame spin detonation was observed at an oxidizer excess ratio below unity, with the spraying process being intensified up to sixfold. The coatings demonstrated high reliability compared to other accelerated systems. The maximum specific heat fluxes on the coating range from 2 to 20×10⁶ W/m², with oscillation frequencies reaching 200 Hz. The overheating range of the coating was (20–75) K. The granulometric composition of the materials was obtained, and the hydrodynamic operating modes of the burners were selected. A model was developed for the interaction of a supersonic detonation gas jet of the thermal tool acting normally to the coating. The experimentally determined heat transfer coefficients were found to be 5–6 times higher than those predicted by laminar theory, and several times lower than those predicted by turbulent heat transfer laws. The particle flight time, powder diameter, as well as the ultimate compressive and tensile stresses of the coating were determined. The main practical application of the research is thermal protection through cooling with natural coatings (quartzites, granites, teschenites, marbles, tuffs) for highly forced and high-intensity structures in the fields of energy, metallurgy, and mechanical engineering. The primary industrial implementation of the research is the use of a thermal tool for spraying, processing of rocks, drilling, and cutting of reinforced concrete structures during modernization and reconstruction of enterprises.

DETERMINATION OF THE ENERGY RELEASE DISTRIBUTION AND TEMPERATURE IN THE IRT-4M NUCLEAR FUEL WHEN CHANGING THE CONFIGURATION OF THE CONTROL AND PROTECTION SYSTEM CHANNELS IN THE WWR-SM REACTOR

Tue, 30 Sep 2025 00:00:00 +0500

The objective of this work is to determine the temperature distribution in the IRT-4M type fuel assembly with fuel 19.75% enriched in ²³⁵U in the core of the WWR-SM reactor for the case of a square tube with rounded edges and a round hole in the center and the case of a round tube. In the case of installing a round tube inside the fuel assembly instead of a square tube with rounded edges and a round hole in the center, the volume of water in this space increases. On the one hand, this leads to improved heat removal, since the volume of cooling water increases, and on the other hand, an increase in the volume of water leads to an increase in thermal neutrons on this side of the fuel element, and this, in turn, leads to an increase in energy release. To determine these changes, we performed neutron-physical and thermal-hydraulic calculations for a channel with a square tube with rounded edges and a round hole in the center and for a round tube. It has been determined that replacing a square tube with rounded edges and a round hole in the center with a round tube as a guide for installing a compensating control rod will not affect the nuclear safety of the WWR-SM reactor operation.

OPTICAL SPECTROSCOPIC DIAGNOSIS OF ELECTRON TEMPERATURE AND DENSITY FOR ZN-AL ALLOY PLASMA: EFFECT OF LASER ENERGY ON PLASMA PARAMETERS

Mohammed H. Jawad, M.R Abdulameer (Author) — Tue, 30 Sep 2025 00:00:00 +0500

In this study, the properties of plasma produced from zinc and aluminum alloy were investigated using laser spectroscopy techniques. The alloy was locally manufactured and consisted of 20 to 80 percent zinc and aluminum, respectively. Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) laser with a fundamental wavelength of 1064 nm was used with a variable laser energy from 500 to 900 mJ In order to study the behavior of plasma and determine its general properties such as electron density and temperature. Boltzmann plot method was employed to ascertain the temperature of the electrons, in addition to using Stark expansion method to calculate the electron density. Based on these two basic parameters, the rest of the additional plasma parameters were calculated and determined. The results obtained from this study showed that there is a clear effect of laser energy on the plasma parameters, as the temperature and electron density increased significantly with the increase in laser energy, as these parameters gradually increased with the increase of laser energy. The maximum value of the electron temperature was 0.918 eV at 900 MJ, while the electron temperature was 0.537 eV at 500 mJ. On the other hand, the results showed an increase in both the Debye number and plasma frequency at high laser energies, while the Debye length showed a clear decrease at high power. The main purpose of this study is to contribute to a deeper understanding of the properties of plasma and how laser power affects these properties, which opens the way for many applications, including engraving and marking on metals and many industrial and technological applications.

SUBSTITUTIОN ОF THERMАL-TECHNICАL АND GEОMETRIC PАRАMETERS ОF А SMАLL-SCАLE BIОGАS PLАNT

Tue, 30 Sep 2025 00:00:00 +0500

This article is devoted to the issues of justification of thermal-technical and geometric parameters for small-scale biogas devices. The growing demand for sustainable and renewable energy resources has increased the importance of biogas technologies, particularly at the small-scale level for rural and agricultural applications. However, the efficiency and stability of biogas production largely depend on the thermal-technical conditions of the digester and the optimization of its geometric parameters. The purpose of this study is to analyze the effect of substituting thermal-technical and geometric parameters on the performance of a small-scale biogas plant. The research object is a laboratory-scale biogas digester with adjustable design features. Methodologically, the work is based on mathematical modeling, computational analysis, and experimental validation of heat transfer and mass balance processes inside the digester. From the results of the resulting study, it can be seen that the methods of determining the optimal geometric dimensions (diameter and length) of the bioreactor structure and reducing heat losses have been analyzed. Mathematical modeling methods have been used to calculate the optimal reactor diameter for various thermal insulation thicknesses and biomass dosing, and the optimal diameter for a 30 m³ bioreactor is 2800 mm, while the length is 4900 mm, the proportion of biomass in the reactor volume is expressed by the central sector angle.