Scientific and Technical Journal of Namangan Institute of Engineering and Technology

STUDY ON DETERMINING THE BENDING AND TORSIONAL STIFFNESS OF PACKAGED WORKING BODIES

2026-01-27T17:05:37+05:00

The article reports on the study of bending and torsion of a package of alternating flat working and spacer disk elements, assembled by means of longitudinal compressive force. As a result, a phenomenological method for determining the bending and torsional stiffness of such structures is substantiated.

INFRARED SPECTROSCOPIC ANALYSIS OF THE PURIFICATION OF SUNFLOWER OIL FROM WAXY SUBSTANCES USING PERLITE AND VERMICULITE

2026-01-27T14:32:03+05:00

This article investigates the effectiveness of perlite as a filtering agent for the removal of waxy substances from sunflower oil during the winterization process. Sunflower oil tends to become cloudy at low temperatures due to the presence of wax esters, phosphatides, and other wax-like compounds, which negatively affect its appearance and commercial value. In the experimental procedure, the oil was cooled to 7–8 °C to initiate wax crystallization and then filtered through perlite. The filtration efficiency was evaluated using infrared (IR) spectroscopy, which allowed for the identification of functional groups associated with waxy substances. The study also examined the regeneration potential of perlite by subjecting the used filter material to thermal treatment and reusing it in repeated cycles. Physicochemical properties such as porosity and structural stability were also assessed. The IR spectra confirmed that regenerated perlite retained its filtering capabilities. Overall, the results show that perlite is an effective and reusable natural adsorbent for improving the clarity and quality of sunflower oil.

THEORETICAL FOUNDATIONS FOR ENSURING THE MECHANICAL STRENGTH OF PAPERS CONTAINING COLLAGEN HYDROLYSATES

2026-01-27T14:40:05+05:00

The study explores the influence of fibrous raw materials, refining processes, and adhesive substances on the development of strength properties in paper and cardboard products. Special attention is given to the role of fiber morphology, cellulose refining, and interfiber bonding in improving paper quality. The paper highlights that refining significantly alters the surface structure of fibers, leading to increased fibrillation and enhanced bonding potential, which directly affects the structural and mechanical properties of the paper web. In particular, the study emphasizes the contribution of collagen hydrolysate, an organic additive, in forming fibrillar structures within cellulose and modified polyacrylonitrile (MPAN) fibers, thereby strengthening interfiber adhesion. The findings underline the dual role of structural-mechanical and chemical factors in advancing the physical and mechanical properties of paper.

RESEARCH ON THE PRINTING AND TECHNICAL PROPERTIES OF KRAFT PAPER INCORPORATING "COTTON CELLULOSE-INDUSTRIAL WASTE-PACULATE"

2026-01-27T14:42:52+05:00

In this study, to conserve valuable cotton cellulose, the paper pulp was composed of light industrial cocooning waste from our Republic (specifically, the mat and fiber produced during cocooning at the Margulon "IPAKCHI" joint-stock company) and secondary paper waste (MS-3A). Binders and adhesives were used in the preparation process. The kraft paper samples were prepared in the test laboratory of the "Global Komsco Daewoo" joint venture.

STUDY OF INTERACTION OF COMPONENTS IN THE H3BO3–KNO3–H2O SYSTEM

2026-01-27T15:17:50+05:00

The interaction of boric acid with potassium nitrate, the main component of NPK fertilizers, was studied in 0.01 M dilute solutions using the isomolar sequence method. To determine the possible direction of the reaction in the H₃BO₃ – KNO₃ – H₂O system, changes in the properties of pH, density, refractive index, viscosity and crystallization temperature of mixtures of 0.01 M boric acid and potassium nitrate solutions in different ratios were determined. The inflection points of the “composition-pH”, “composition-density”, “composition-viscosity” and refractive index dependences were determined. Regardless of the initial concentration of boric acid, when a small amount of potassium nitrate was added, the composition of the solution changed.

ABOVEGROUND COMPONENTS OF SALVIA SARAWSCHANICA

2026-01-27T15:28:12+05:00

Using the GC-MS method, 36 compounds were identified in the essential oil obtained by hydrodistillation from the air-dried above-ground part of Salvia sarawschanica by Regel et Schmalh, which constituted 95.1% of the total oil. The main components of the EO are 1,8-cineole, camphene, camphor, aromadendrene and limonene, the content of which was 33.8, 12.3, 6.8, 5.2 and 4.9%, respectively. Four individual phenolic compounds were isolated from various fractions of the 80% alcoholic extract of the roots of S. sarawschanica, which, based on the study of the ¹H, ¹³C NMR, HSQC and HMBC spectra, were identified with acacetin, luteolin, cynaroside, luteolin-3'-O-β-D-glucuronide. Essential oil from the above-ground parts of the plant S. sarawschanica exhibits a noticeable antibacterial effect against the gram-positive strain of bacteria B. subtilis.

ZEOLITE‑BASED BIMETALLIC COMPOSITE CATALYSTS FOR PYROLYSIS AND GASIFICATION: CHEMICAL TECHNOLOGIES FOR DEEP BIOFUEL UPGRADING AND CONVERSION INTENSIFICATION

2026-01-27T15:35:57+05:00

The use of biofuels in electricity and heat supply helps conserve fossil fuel resources and offers a pathway to mitigate environmental problems. In this context, processing agricultural residues and employing them as biofuels can provide an effective answer to energy challenges not only in Uzbekistan but also in many other countries. From this standpoint, our research prioritizes the purification of biofuels using zeolites, the separation of high‑purity xylenes and other aromatic compounds, and the acceleration of reaction processes by preparing zeolite‑based bimetallic composite catalysts that further improve fuel quality. Zeolites are a class of crystalline materials with molecularly ordered microporous structures. In recent years, their use in converting biomass and wastes into fuels has advanced considerably. Zeolite catalysts play a key role in enabling the efficient conversion of energy carriers into chemicals and fuels; however, their specific functions in biomass utilization remain insufficiently defined. In this article, we present an in‑depth analysis of biomass pyrolysis and upgrading using zeolites, the selection of appropriate zeolite types, and the adsorption properties of ortho‑, meta‑, and para‑xylene on BaY zeolite. The results are compared on the basis of adsorption isotherms, differential heats, and entropy metrics.

USE OF BaNaY FAUJASITE ZEOLITE–BASED BIMETALLIC COMPOSITE CATALYSTS FOR DEEP BIOFUEL PURIFICATION AND SELECTIVE XYLENE SEPARATION

2026-01-27T15:40:26+05:00

The use of biofuels in electricity and heat supply is a key pathway for conserving fossil resources and lowering environmental burdens. In particular, converting agricultural residues into biofuels can enhance energy security in Uzbekistan and many other countries. This study prioritises deep purification of biofuels using zeolites, selective recovery of high‑purity xylenes and other aromatics, and acceleration of reaction rates via zeolite‑based bimetallic composite catalysts (Ni, Fe, and Ni–Fe systems) to improve overall fuel quality. Zeolites are crystalline sorbent–catalysts with molecularly ordered microporous frameworks whose importance in biomass upgrading (pyrolysis, gasification) has grown markedly; nevertheless, questions remain about their specific functions, selectivity limits, and stability in biomass‑derived vapours. Here, we set out the scientific basis for zeolite‑assisted pyrolysis and subsequent upgrading, and present a detailed assessment of the adsorption behaviour of ortho‑, meta‑, and para‑xylene on BaNaY (FAU) zeolite. The results are compared using adsorption isotherms, differential heats of adsorption, and entropy metrics, enabling a thermodynamic‑selectivity analysis that supports the use of FAU‑type sorptive polishing together with Ni/Fe and Ni–Fe catalytic functionalities in advanced biomass‑to‑fuel processes.

ON THE STUDY OF PHYSICOCHEMICAL PROPERTIES OF SOILS IN THE REGIONS OF THE REPUBLIC

2026-01-27T15:48:13+05:00

In the case of increasing anthropogenic load and changing climate factors, the study of the physical properties of soils in various regions of the Republic is becoming especially relevant. Particular emphasis is placed on the parameters of water-holding capacity, sorption ability, bulk density, and porosity, as these factors play a decisive role in the productivity of agroecosystems and the stability of land resources. In this study, a detailed analysis of serozem and saline soils was performed using desiccator-based water vapor sorption isotherm techniques, complemented by the application of structure-modifying additives of organic and polymeric nature. Various doses of additives (sulfonyl and carboxymethyl cellulose) were used in varying doses for 50 g of air-dry soil in the experimental part. An increase in specific surface area and porosity is achieved by adding it, but sulfonyl and its composite systems have a more noticeable impact on capillary moisture. The comparative analysis revealed that optimal dosages provide an increase in moisture capacity of up to 20-25% compared to control samples. Therefore, the obtained results contribute not only to a deeper understanding of the physical properties of soils but also provide practical guidance on the application of organic additives aimed at improving agronomic qualities and increasing the efficiency of reclamation measures under the conditions of the Republic.

OPTIMIZED CHEMICAL SYNTHESIS OF STABLE SILVER NANOPARTICLES USING VARIOUS REDUCING AND STABILIZING AGENTS

2026-01-27T15:55:38+05:00

This article discusses the influence of stabilizing agents on the stability and particle size of silver nanoparticles (AgNPs) during synthesis. AgNPs were synthesized via chemical reduction of silver nitrate (AgNO₃) using different reducing agents (sodium citrate, hydrazine, glucose) and stabilizers (gelatin, dextrin, and PVP). Syntheses were conducted under various temperature conditions (0°C, 20°C, 40°C), and the particle size of the resulting nanoparticles was measured using the MasterSizer-3000 laser diffraction method. The most stable AgNPs were obtained using sodium citrate as a reducing agent and 1% gelatin as a stabilizer at 20°C. Under these conditions, the synthesized particles exhibited small and uniform size and remained stable for up to 6 months without sedimentation. Increasing the temperature led to the formation of larger particles. Sodium citrate and gelatin represent an optimal combination for the controlled and stable synthesis of AgNPs. This approach offers promising applications in medicine, biotechnology, and environmental sciences.

INVESTIGАTIОN ОF THE АDSОRPTIОN PRОPERTIES ОF THE SОRBENT ОBTАINED IN THE PRОCESS ОF MОDIFICАTIОN ОF CLINОPTILОTHITE IN THE PURIFICАTIОN ОF NАTURАL GАS FRОM SULFUR CОMPОUNDS

2026-01-27T16:03:35+05:00

The study оf the pоssibility оf using mоdified clinоptilоlite аs аn аdsоrbent аnd the аdsоrptiоn prоperties оf zeоlite in the purificаtiоn оf nаturаl gаs supplied tо gаs prоcessing plаnts frоm sulfur cоmpоunds cоntаined in it is аn urgent tаsk. In the experimentаl study, the аdsоrbent frаctiоn wаs chоsen аs 0.5÷1.0 mm, density - 0.8 g/cm³, аdsоrbent lаyer height - 600 mm. Оptimаl cоnditiоns аre selected in such а wаy thаt the pressure in the experimentаl prоcess is 0.2-5.0 MPа, the аmоunt оf mercаptаns in the purified nаturаl gаs is 50÷400 mg/nm³, the temperаture is 20÷25°C, the gаs flоw rаte is 0.2÷0.25 m/s. The intensity аnd аccurаcy оf desоrptiоn оf sulfur cоmpоunds аdsоrbed оn clinоptilоlite аt 250°C, the sаme results were оbtаined оn NаX zeоlite аt 320°C. The cаtаlytic аctivity оf regenerаtiоn оf clinоptilоlite аt lоwer temperаtures thаn thаt оf NаX zeоlite, аlthоugh smаll, mаde it pоssible tо minimize the decоmpоsitiоn оf mercаptаns. Аdsоrptiоn оf 200 mg/nm³ оf mercаptаns in mоdified clinоptilоlite in less thаn 30 minutes, this figure wаs recоrded fоr 150 minutes in zeоlite NаX.

ADSORPTION ISOTHERM OF HYDROGEN SULFIDE ON AN ACTIVATED ADSORBENT DERIVED FROM HYBRID PAULOWNIA TOMENTOSA WOOD

2026-01-27T16:19:47+05:00

This study presents the results of investigating the adsorption isotherms of hydrogen sulfide on a carbonaceous adsorbent derived from Paulownia tomentosa (woolly paulownia) wood using the steam–gas activation method. The thermodynamic and structural parameters of the sorbent were examined, which determine its high sorption capacity and chemical stability during interaction with H₂S. Steam–gas activation of Paulownia tomentosa charcoal was carried out at controlled temperatures (700–850 °C) using water vapor as the activating agent. The resulting adsorbent exhibited a well-developed microporous structure and a high specific surface area (up to 1100 m²/g). The adsorption isotherms of H₂S at 303 K were studied using microcalorimetry and static adsorption methods. It was found that the adsorption process is of a physico-chemical nature, indicating a predominantly monomolecular mechanism of interaction. Analysis of the linear portion of the adsorption isotherm showed that the number of active sites on the adsorbent surface is 0.54 mmol/g. This value reflects the high activity of the microporous structure and the presence of polar functional groups on the sorbent surface. Furthermore, the results indicate that the interaction between the adsorbate and the adsorbent occurs through the formation of a complex in a 3:1 ratio (3H₂S:C) at the active sites. Such an interaction pattern suggests a monomolecular adsorption mechanism of H₂S and confirms the high selectivity, stability, and efficiency of the carbonaceous adsorbent in gas purification processes. The obtained results demonstrate that steam-activated carbon derived from Paulownia tomentosa is a promising sorbent for hydrogen sulfide removal from gas streams, offering high capacity, stability, and environmental safety. This work opens opportunities for further optimization of activation conditions and surface modification to enhance the efficiency of natural and industrial gas purification.

OPTIMIZATION OF THE AQUEOUS SOLUBILITY OF MONOAMMONIUM PHOSPHATE, POTASSIUM NITRATE, AND MAGNESIUM NITRATE VIA THERMODYNAMIC ANALYSIS AND SELECTIVE CRYSTALLIZATION

2026-01-27T16:55:57+05:00

This study investigates the solubility behavior of monoammonium phosphate (NH₄H₂PO₄, MAP), potassium nitrate (KNO₃), and magnesium nitrate (Mg(NO₃)₂) in aqueous media within binary and ternary systems using a thermodynamic–phase analysis framework. The polythermal (S–T) approach was employed to parameterize the temperature–solubility relationship; the solubility gradient dS/dTand van ’t Hoff plots were used to obtain approximate values of the dissolution enthalpy ΔH_"sol" . Phase diagrams—interpreted via the Gibbs phase rule, Schreinemakers construction, tie lines, and the lever rule—were utilized to delineate crystallization fields. Based on these results, we propose integrated selective-crystallization regimes combining PID-controlled cooling, seeding, on-line refractometry/densimetry, and mother-liquor recirculation.

STUDY OF THE CHEMICAL AND MINERALOGICAL COMPOSITION OF THERMAL POWER PLANT WASTES

2026-01-27T17:01:16+05:00

The paper presents the results of a comparative study of ash–sludge wastes generated from the combustion of coal and natural gas at the Takhiatash Thermal Power Plant. Using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) methods, the morphological and chemical differences between the studied samples were determined. It was shown that coal-derived ash–sludge wastes are characterized by a porous, heterogeneous structure and a high content of silicon, aluminum, and calcium; whereas gas-derived wastes predominantly contain iron oxides and exhibit a denser and more homogeneous structure. The obtained results indicate the potential applicability of these technogenic materials as sorbents, catalysts, and additives in construction composites.

ENERGETICS OF WATER MOLECULE ADSORPTION ON MODIFIED BENTONITE SURFACES

2026-01-27T14:24:28+05:00

In this study, the energetics of adsorption of water molecules on modified (enriched and activated) Dehkanabad bentonite were studied in depth. Based on experimental data, adsorption isotherms and differential heats of adsorption (Qd) were determined, and molar differential entropy (ΔSd) values were calculated using the Gibbs–Helmholtz equation. The results of the study showed that water molecules adsorbed on the surface of modified bentonite in a stepwise manner, and the values of adsorption heat and entropy changed depending on the degree of surface filling. In the initial stages, high-energy adsorption centers were active and characterized by high heat (~71.7 kJ/mol), while in the later stages, the heat decreased and manifested itself in the form of plateaus. Entropy analysis revealed that the mobility and disorder of water molecules in the surface phase were sometimes higher than that of liquid water. Kinetic observations showed that the time to reach adsorption equilibrium depends on the degree of surface coverage and the redistribution of structural cations. The results of this work provide an important scientific basis for assessing the efficiency of modified bentonite-based sorbents in absorbing water vapor and determining the directions of their practical application.

THE STUDY TORSION FLUCTUATIONS PACKET WORKER ORGAN WITH PROVISION FOR INFLUENCES OF THE CORRELATION LONGITUDAL ACERBITY THEIR ELEMENT

2026-01-27T17:07:59+05:00

In article about torsion fluctuation worker of the organ, consisting of package compressed by sprained gross disc element, working as monolithic body, and influence upon its torsion of the fluctuation of the sidebar internal effort, formed by package and gross and is shown way of the analytical account of this influence.

ENERGY-INTEGRATED SMART TEXTILES: INTERNATIONAL TRENDS AND PROSPECTS FOR UZBEKISTAN’S RESEARCH ECOSYSTEM

2026-01-27T17:11:40+05:00

Smart textiles—also known as electronic textiles (e-textiles)—represent a rapidly growing field in which flexible fabrics are embedded with electronic components to provide advanced functionality such as real-time sensing, data processing, and wireless communication. This study presents a modular analysis of smart textile systems by exploring five core components: sensors, microcontrollers, actuators, communication interfaces, and energy storage units. Emphasis is placed on energy autonomy through the integration of gel polymer electrolyte (GPE)-based supercapacitors, thermoelectric generators (TEGs), and piezoelectric yarns. International case studies from institutions such as MIT, KAIST, and the Chinese Academy of Sciences are used to benchmark global progress. The interdisciplinary convergence of materials science, electronics, and textile engineering is highlighted as a key enabler of innovation. The paper concludes with practical recommendations aimed at advancing national research infrastructure and accelerating the commercialization of smart wearable systems.

INTEGRATED GENETIC‑DIFFERENTIAL EVOLUTION APPROACH FOR SIMULTANEOUS PRESSURE‑DROP REDUCTION AND EFFICIENCY ENHANCEMENT IN MULTI‑CYCLONE DUST COLLECTORS

2026-01-27T17:22:02+05:00

This study shows how to “hit two targets with one math‑arrow,” trimming pressure drop (ΔP) down while cranking collection efficiency (η) up in industrial multi‑cyclone (MSC) dust collectors. A CFD‑based response‑surface “crystal ball” is hitched to a tag‑team optimizer—Genetic Algorithm leads, Differential Evolution finishes—then polished by an NSGA‑II Pareto “red‑carpet” filter. The quartet of tweakable dimensions (barrel diameter D, inlet width B, cone length L_c, vortex‑finder diameter D_v) forms the playground. The GA → DE relay squeezes the composite score from J = 1.00 to J = 0.17, slicing ΔP by 32 % and boosting η by 9 %. For a medium‑sized plant the makeover shaves roughly 14 MWh year⁻¹ of fan energy—about 11 t CO₂ that never see daylight—proving that a little mathematical wizardry can make cyclones spin greener and leaner.

TECHNOLOGICAL PRINCIPLES FOR CREATING A SUIT THAT ENSURES HIGH RELIABILITY AND SAFETY IN AQUATIC ENVIRONMENTS

2026-01-27T17:25:17+05:00

This article analyzes the technological foundations for creating a specialized suit that ensures high reliability and safety in aquatic environments. The study examines hydrodynamic conditions, the water resistance of materials, heat transfer, and compliance with ergonomic and biomechanical requirements. The rationale for applying functional zoning, a multilayer structure, and innovative sewing technologies in the suit’s construction is substantiated. Based on the research findings, scientific and practical recommendations have been developed for designing a high-performance and safe suit.

THEORETIC OBSERVATION OF THE COTTON MOVEMENT IN THE OPERATING CAMERA OF THE NEW SEPARATOR

2026-01-27T17:35:28+05:00

The Studies moving the pat product in its raw state in worker to camera of the separator to new design. In given article explored moving the pat-product in its raw state in worker to camera of the separator in new designs. Will Formed differential equation moving the pat and are received analytical decision, characterizing laws motion from time.

INVESTIGATION OF THE INTERACTION BETWEEN THE MOVING SEPARATOR SCREEN SURFACE AND THE COTTON MASS

2026-01-27T17:40:10+05:00

This article theoretically substantiates an improved design of a cotton separator device that separates cotton from the air stream. In the proposed modification, the mesh surface in the working chamber of the device has been structurally altered compared to existing analogues — its volume was optimized, and it was mounted as a moving surface. A mathematical model of the process was developed, and corresponding graphical results were obtained to analyze the dynamics of cotton-air separation.

CRITERIA, INDICATORS AND LAWS OF SMALL BUSINESS DEVELOPMENT

2026-01-27T17:52:33+05:00

The possibility of increasing the efficiency of entrepreneurial activity depends on the level of substantiation of strategic directions in the field of production of competitive products and the organization of their introduction to the market in accordance with the logic of economic actions in dynamic market conditions. The process of economic reform is aimed at developing market infrastructure, intensifying competition and the manifestation of its stimulating innovative properties, forming effective mechanisms for the structural restructuring of the national and regional economy, creating sustainable production and market communications, as well as promoting entrepreneurship.

CONCEPT OF ASSESSMENT OF THE ECONOMIC DEVELOPMENT POTENTIAL OF SMALL BUSINESS AND ITS EVALUATION

2026-01-27T17:55:26+05:00

Small businesses are a vital part of any economy, providing jobs, income, and goods and services to communities around the world. “According to the Small Business Administration (SBA), there are more than 31 million small businesses in the United States alone, employing nearly 60 million people. [1] However, despite their importance, many small businesses fail in their first few years of operation. Small businesses play a crucial role in the economy of any country. They are the backbone of the economy, contributing to job creation, economic growth, and social development. Small businesses create jobs and provide employment to millions of people around the world. “In most countries, small businesses account for a significant portion of total employment. According to the World Bank, small and medium-sized enterprises (SMEs) account for more than 90% of businesses worldwide and contribute to more than 50% of total employment.” [2]

ECONOMETRIC ANALYSIS OF THE ACTIVITIES OF MULTI-SECTORAL FARMS

2026-01-28T09:20:04+05:00

Projections indicate that the global demand for food products will rise by nearly 60 percent by 2050, presenting one of the most pressing challenges for agriculture and food systems. This surge in demand must be met under conditions of climate change, finite natural resources, and shifting consumption patterns driven by demographic growth, urbanization, and income dynamics. In developing countries, the responsibility for addressing this challenge disproportionately falls on small-scale producers, who account for the majority of food production. Their role is critical not only for ensuring food security at the national level but also for sustaining rural livelihoods and contributing to broader economic resilience. However, their potential is often constrained by limited access to technology, markets, finance, and infrastructure, which amplifies their vulnerability to environmental and economic shocks.

GLOBAL DIGITALIZATION: PATHS AND PROBLEMS

2026-01-28T09:22:34+05:00

During the twentieth century, one of the most striking global shifts was the integration of the Internet into virtually every dimension of human activity. The acceleration of economic and entrepreneurial practices under the pressure of fast-evolving online technologies has reshaped traditional patterns and given rise to what is now recognized as the digital economy. Within this framework, innovative digital tools serve as key drivers for unlocking new potentials: enhancing efficiency of business processes, reducing operational expenditures, creating alternative channels for capital mobilization, and expanding opportunities for the advancement of entrepreneurial initiatives. Enhancing the performance of the digital economy through the application of advanced science and technology, stimulating consumer demand for goods and services, and ensuring the delivery of high-quality products by integrating modern equipment and technologies into production processes have become the central priorities of the global economic agenda. At present, the contribution of the digital economy to the gross domestic product differs markedly across countries: it constitutes 5.5% in developed economies and 4.9% in developing ones. More specific figures demonstrate considerable variation — 12.4% in the United Kingdom, 8% in South Korea, 6.9% in China, 5.6% in India, 2.8% in Russia, and 3.9% in Kazakhstan [1].

PROSPECTS FOR DEVELOPMENT AND IMPROVEMENT OF THE MECHANISM OF FUNCTIONING OF THE STOCK MARKET

2026-01-28T09:26:50+05:00

The article analyzes modern trends in the development of the stock market of the Republic of Uzbekistan. The main problems hindering its development are considered. Solutions to some of the existing problems are presented, and priority areas for further development and improvement of the mechanism of functioning of the stock market are determined.

DIRECTIONS FOR EFFECTIVE USE OF RESOURCES IN IMPROVING THE QUALITY OF SERVICES IN THE HIGHER EDUCATION SYSTEM

2026-06-30T13:33:16+05:00

Improving the quality of services in the higher education system is ensured by the correct allocation of resources,
their strategic management and the use of performance-oriented approaches. This article provides a detailed analysis of the
theoretical foundations, practical problems and effective directions of these processes.

STUDY OF THE DYNAMICS OF THE DRIVE MECHANISM OF MOVING NEEDLES

2026-01-22T18:45:35+05:00

This article examines design issues and calculations that take into account the dynamic nature of loads acting on machines. As is well known, all bodies with mass and elasticity are capable of oscillatory motion. Unwanted vibrations in a mechanism can reduce the strength of the connection between parts, disrupt the machine's technological process, or ultimately lead to failure of the mechanism or machine. The goal of vibration analysis is to determine the parameters of an oscillatory system that will ensure optimal operating conditions.

UO‘K 621.314.2 DETERMINATION OF ENERGY LOSS IN THE MAGNETIC CORE OF OIL POWER TRANSFORMERS UNDER LONG-TERM OPERATION CONDITIONS

2025-07-08T12:14:28+05:00

Maqolada yog 'kuch transformatorlarining magnit yadrolarida uzoq muddatli ishlash natijasida energiya yo'qotishlari tahlil qilinadi. Tadqiqotda yuksiz rejimdagi magnit yo'qotishlar - histerezis va girdab oqimlari tufayli yo'qotishlar alohida ahamiyatga ega. Ushbu ish mavjud standartlarga asoslangan hisoblash metodologiyasini tavsiflaydi, vaqtga bog'liq energiya yo'qotishlarini hisoblash uchun o'lchovga asoslangan yondashuvlar va formulalarni taqdim etadi. Bundan tashqari, magnit induksiyaga qarab regressiya tenglamalari asosida magnit yadro materiallarining o'ziga xos yo'qotishlarini aniqlash mumkin edi. Taklif etilayotgan yondashuv ishlaydigan transformatorlarning texnik holatini baholash, kapital ta'mirlash zarurligini aniqlash va yangi transformatorni tanlashda muhim ahamiyatga ega.

The STUDY OF THE NATURE AND PROSPECTS OF PRACTICAL APPLICATION OF THE MAGNETOCALORIC EFFECT IN ENERGY-EFFICIENT COOLING SYSTEMS

2025-08-21T12:45:12+05:00

This article presents the results of the analysis of the magnetocaloric effect (MCE), its physical nature, and the prospects for its application in magnetic cooling systems. Special attention is paid to the thermodynamic relationships describing the change in temperature of magnetic materials during adiabatic magnetization and demagnetization. Materials with giant MKE, including rare-earth magnetics and their alloys, were considered, with an assessment of their suitability for use in household and industrial magnetic refrigeration units. It has been shown that the efficiency of MKE depends on magnetic entropy, heat capacity, and the properties of the working medium. Modern approaches to calculating and experimentally determining MKE are presented, as well as models of magnetic refrigeration machines based on cyclic magnetization and demagnetization of working bodies.

UDK 677.051 RESEARCH ON THE OPTIMIZATION OF THE SAW GIN’S ROLL BOX

2025-09-06T13:10:23+05:00

Abstract: The improvement of saw gin machines, particularly their roll boxes, plays a crucial role in increasing the efficiency of cotton processing in the textile industry. The density of the seed roll inside the roll box directly affects productivity, energy consumption, and the degree of fiber damage. Numerous studies indicate that when density exceeds the optimal range of 325-550 kg/m³, the fiber quality deteriorates and machine productivity decreases. Therefore, modern engineering solutions, such as the introduction of accelerators, modified saw cylinders, and lifting mechanisms, have been proposed to regulate density and stabilize the ginning process. This paper presents a comprehensive analysis of structural modifications, operational parameters, and mechanisms applied in modern saw gin machines. Various types of accelerators – disk, blade, and elastic systems – are evaluated in terms of their contribution to fiber quality improvement and energy efficiency. Additionally, the role of automation, including pneumatic lifting devices and sensor-based control systems, is discussed as a means to optimize machine performance. The results demonstrate that the application of innovative accelerators, optimized saw parameters, and pneumatic mechanisms contributes to reducing fiber damage, stabilizing throughput, and increasing overall productivity. The research findings are expected to provide a theoretical and practical foundation for the development of advanced gin machine designs suitable for Uzbekistan’s cotton industry.

621.383 RESEARCH OF MECHANICAL PART OF SOLAR PHOTOVOLTAIC POWER STATION

2025-09-09T10:32:19+05:00

In dusty atmospheric conditions, various dust particles settle on their surface, which, depending on their thickness, damage the tempered glass, reduce the service life of the panels, and also prevent photovoltaic elements from receiving more sunlight, as a result, their temperature increases, the output power, short-circuit current and, therefore, the efficiency factor decrease by up to 50%. Therefore, in order to increase the efficiency and maintain the operability of solar panels, it is considered important to examine the solar panels of solar photovoltaic stations for dustiness This article considers a photovoltaic station, which was built first on the territory of Uzbekistan. This station, with a capacity of 130 kW, was launched in test mode so that test modern four type of solar in the natural and climate conditions of Uzbekistan, train personnel in the field of solar energy, improve skills in the operation of photovoltaic station, as well as to identify practical conclusions on the basis of which in the future to choose the most effective solutions It was determined that with a contaminated optical area, as well as the absence of cooling and orientation mechanisms, short circuit current of a 250 W solar panel deviates on average from the rated value by almost 27 %, and after cleaning the deviation is 12,85 %, which means that it is possible to increase short circuit current by an average of 10-15 % by regularly cleaning the surface, thereby increasing the generation of the solar power stations itself.

CALCULATION OF ABSORPTION COEFFICIENT OF ORGANIC DYE N719 FOR DYE-SENSITIVE SOLAR CELL (DSSC)

2025-09-09T12:49:05+05:00

Abstract: The paper presents a review of literature articles devoted to the study of the effect of dye on the operation of solar cells based on titanium oxide. The absorption coefficient of the organic dye based on rhytinium N719 for dye-sensitive solar cells (DSSC) was calculated, and the light path on TiO₂ was calculated based on the Bouguer–Lambert–Beer equation, taking into account the porous structure of the anode layer. It is shown that the effective layer thickness in the porous structure exceeds the physical thickness by 5–10 times, which ensures a high absorption rate of photons in the visible range.

661.152.5 Research on the separation of zinc from metallurgy waste with a mixture of ammonia and ammonium salts

2025-09-11T14:02:19+05:00

To involve the dust of the "Bekabad" metallurgical combine in the production of complex NPK fertilizers, studies were conducted on several factors such as the duration of processes, the ratio of solid and liquid substances S:L, and temperature in the extraction of zinc from the dust with molar ratios of ammonia and ammonium salts. In this study, an ammonia-ammonium chloride mixture was selected as the most suitable liquidant to achieve high zinc leaching efficiency.

677.21.021 QUALITY INDICATORS OF COTTON FIBER ANALYZED

2025-09-18T16:01:25+05:00

Maqolada To‘raqo‘rg‘on paxta tozalash korxonasida ishlab chiqarilayotgan Andijon 36 paxta navining arrali jindan oldingi paxta tolasi va arrali jindan keyin ajratib olingan tolada o‘tkazilgan laboratoriya taxlil natijalari HVI 900 tizimi hulosalari keltirilgan.

CIRCULАR ЕCОNОMY РRАCTICЕS IN THЕ TЕXTILЕ INDUSTRY: CURRЕNT STАTUS, INDICАTОRS, АND DЕVЕLОРMЕNT ОРРОRTUNITIЕS

2026-01-22T17:13:20+05:00

Thе tеxtilе sеctоr rаnks аmоng thе lаrgеst industriеs wоrldwidе, with its mаrkеt vаluе рrоjеctеd tо rеаch USD 2.25 trilliоn by 2025. Rising еnvirоnmеntаl аwаrеnеss hаs sрurrеd incrеаsеd еffоrts tо аdорt sustаinаblе аnd circulаr рrоductiоn аррrоаchеs. This rеsеаrch еxрlоrеs circulаr еcоnоmy (CЕ) strаtеgiеs within thе tеxtilе аnd арраrеl industry, еmрhаsizing rеsоurcе орtimizаtiоn, rеcycling, rеnеwаblе fibеr usаgе, аnd digitаl innоvаtiоns. Findings rеvеаl thаt thе tyре оf tеchnоlоgy еmрlоyеd, thе scаlе оf ореrаtiоns, аnd thе dеgrее оf suррly chаin intеgrаtiоn significаntly аffеct CЕ imрlеmеntаtiоn аnd thе sеctоr’s sustаinаbility оutcоmеs. Аdditiоnаlly, thе study highlights kеy chаllеngеs, succеss fаctоrs, аnd реrfоrmаncе mеtrics, оffеring guidаncе fоr futurе rеsеаrch аnd роlicy initiаtivеs. Thеsе insights аrе раrticulаrly usеful fоr schоlаrs, industry lеаdеrs, аnd роlicymаkеrs sееking tо аdvаncе CЕ рrаcticеs in tеxtilеs.

FORECASTING THE TEMPERATURE GRADIENT OF COTTON REVOLT

2026-01-22T17:27:19+05:00

In the context of today’s rapidly developing global economy, which is strongly driven by technological production, the issue of ensuring sustainability and safety in agricultural industries has become particularly relevant. Among the most strategically important industries in the Republic of Uzbekistan, cotton production stands out due to its scale and significant contribution to the national economy. However, one of the most serious challenges in this sector is the risk of spontaneous heating and ignition of cotton storage modules, which can result in substantial economic losses, deterioration of fiber quality, and even large-scale fire hazards. This paper explores scientific and engineering approaches aimed at preventing the ignition of cotton storage formations through accurate forecasting and structural modifications.

OPTOELECTRONIC THREE-WAVE MOISTURE METER OF RAW COTTON

2026-01-22T17:34:27+05:00

The article provides information on the development of a tricolor LED emitter of the middle infrared region of the spectrum, consisting of a measuring LED chip for fibers with a wavelength of 1.8 microns, a measuring LED chip for water with a wavelength of 1.94 microns and a reference LED chip with a wavelength of 2.2 microns, as well as an optoelectronic three-wave moisture meter raw cotton developed on the basis of this tricolor LED emitter.

To improve the accuracy of measuring the moisture content of raw cotton, an optoelectronic three-wave moisture meter has been developed, the presence of three radiation channels allows not only simultaneously monitoring the optical absorption of water and the physicochemical properties of cotton fibers. The moisture meter consists of an exponential voltage shaper, three emitting diodes (emitting at reference, measuring wavelengths and at a wavelength lying in the absorption band of uninformative parameters), a controlled object, a photodetector and a photoelectric signal processing unit.

TECHNIQUES AND DEVICES FOR MITIGATING ENVIRONMENTAL POLLUTION IN COTTON PROCESSING INDUSTRIES

2026-01-22T18:15:15+05:00

This article analyzes the issue of atmospheric pollution caused by particulate matter (PM2.5, PM10) in cotton processing enterprises. The efficiency of conventional dust collection devices—cyclones, cartridge filters, and HEPA filters—is scientifically compared, and their limitations in ensuring environmental safety are identified. Furthermore, the theoretical and practical integration of IoT (Internet of Things)-based smart sensors and GIS (Geographic Information Systems) platforms into industrial monitoring is substantiated. The study develops a block-diagram approach for real-time data acquisition, network-based transmission, and spatial visualization to determine pollution dynamics. Based on the analysis of local and international practices, it has been demonstrated that smart-filter systems can reduce atmospheric pollution by up to 90%. The findings provide a solid foundation for formulating scientifically grounded recommendations on the implementation of digital technologies in the field of industrial ecology.

EFFECT OF THE FORCES ON THE SEPARATION OF FIBER FLOW FROM THE SAW IN AN IMPROVED LOWER FIBER REMOVAL DEVICE

2026-01-22T18:32:15+05:00

In the article is presented an analysis of a fiber bottom stripping device in the cotton gin industry that allows increased airflow rate, consumes less air and improves the efficiency of stripping fibers from saw teeth of the saw cylinder. The effects of forces in isolating the fiber stream from the saw have been studied.

EXPERIMENTAL DETERMINATION OF THE LOAD ON THE MULTIFACETED COLUMNS ON THE ELASTIC SUPPORTS OF THE COTTON GINNER

2026-01-22T18:40:18+05:00

Based on the experiments conducted with a change in the number of grate faces in the cotton dragging zone, it has a sinusoidal (triangular) shape relative to the cotton along the grate faces, with a different angle of location, which leads to the release of impurities of various masses and different depths of presence in the cotton. The force of the impact load has the greatest impact on the amount of released impurities, provided that the natural quality of the fiber is preserved; the distance of the grate from the rotating drum should ensure the free passage of the fly. When a cotton piece hits and interacts with the grate, it is important that the behavior of the specks results in a chaotic arrangement.

TRANSITION FUNCTION OF SECOND-ORDER ELEMENT

2026-01-27T17:47:47+05:00

This work analyzes the denominator of the transfer function of second-order elements widely used in modern automatic control systems - the characteristic equation. The transfer function is calculated and derived, and it is proposed to use the expression of this derived transfer function as a mathematical model for the convenience of identification of second-order inertial elements based on experimental transition characteristics.

DEVELOPMENT OF TECHNOLOGY FOR PRODUCING LEATHER FROM AFRICAN CATFISH SKINS

2026-01-22T18:51:56+05:00

The article develops and substantiates a technological system for processing African catfish skin and producing leather from it. It is emphasized that taking into account the individual characteristics of fish skin during processing creates the prerequisites for obtaining high-quality products. It is established that processing fish skin has socio-economic advantages: it is a renewable resource, facilitates waste utilization, and enables the production of a new range of leather materials. There are two most important new features in this article: one of this is a personalised degreasing protocol for the high lipid content (22.8±2.1%) and second one is better chrome tanning settings that make collagen more stable. The key point of the process is to work at low temperatures and keep the pH level just right so that enzymes do not break down the skin. Although, the leather taken from this process has a grain pattern and mechanical properties that make it good for high-end uses.

THEORETICAL STUDY OF THE QUALITY INDICATORS OF NEWLY STRUCTURED KNITTED FABRICS BASED ON A MATHEMATICAL MODEL

2026-01-22T18:55:57+05:00

Mathematical modeling of the physical-mechanical properties and technological indicators of knitted fabrics, along with their theoretical study through practical experiments, creates opportunities to improve the quality indicators of the resulting knitted products and to make preliminary forecasts during the production process. In turn, this leads to an increase in the parameters of achieving economic efficiency through scientific research.

THEORY OF TORSIONAL VIBRATIONS OF GROOVED CYLINDERS

2026-01-22T19:02:06+05:00

The article addresses one of the most pressing challenges in the modern textile industry - the need to increase the speed of spinning equipment while simultaneously enhancing yarn quality. The key element determining yarn quality is the spinning machine’s drafting device, particularly its corrugated cylinders. Existing studies indicate that the primary causes of yarn unevenness and breakage lie in imperfections of the drafting device, which are associated with geometric errors in the manufacturing of corrugated cylinders, their dynamic characteristics, and torsional vibrations during operation. The problem of joining corrugated cylinders is especially critical, as traditional connection methods lead to deformation and failure in the transition zone. An analysis of scientific and technical literature reveals the absence of a comprehensive approach to solving this issue. Current theoretical studies examine only isolated aspects of drafting device operation without accounting for their interactions. This results in an incomplete understanding of the processes occurring within the corrugated cylinder system and, consequently, hinders the optimization of their performance.

IMPACT OF CALCIUM CHLORIDE ON THE CHEESE YIELD DURING SWISS CHEESE MANUFACTURING PROCESS

2026-01-23T09:42:56+05:00

This study is focus on the impact of calcium chloride on the cheese yield and sensory properties during Swiss cheese manufacturing process. Therefore, a research plan was developed to change the amount of calcium chloride and tested for the yield in grams and sensory analysis using Friedman 5 point scale test. It was revealed that the calcium chloride addition is having a positive correlation and the optimum level of adding calcium chloride in cheese was 0.02% and while having decreasing rate of yield when it was increase beyond 0.02%. also, sensory properties of the cheese revealed that the 0.02% of calcium chloride was having good sensory and organoleptic properties and there was a taste issue observed when the calcium chloride increased beyond 0.02%. Therefore, it can be concluded that the calcium chloride is having a strong linkage between casein protein and it induces the reaction rate while increase the yield of the cheese and the sensory qualities of Swiss cheese manufacturing process.

ANALYSIS OF THE INFLUENCE OF THE WHITENING PROCESS DURING PREPARATION FOR FLOURING ON THE QUALITY OF BAKERY FLOUR MADE FROM A MIXTURE OF WHEAT AND RYE GRAINS

2026-01-23T09:47:44+05:00

The article experimentally studies the effect of different methods of dry processing of the surface of local wheat and rye grains when preparing them for grinding into fine flour and their aging process during storage. The purpose of the study is to experimentally study the effect of different methods of dry processing of the surface of wheat and rye grains when preparing them for grinding into fine flour on the quality of bread products and their aging process. Materials and methods of research, sample bread was prepared from flours milled from a mixture of wheat and rye grains selected for the study in accordance with GOST 27669-88, their technological quality indicators were analyzed , and the results were processed using the full-factorial experimental method. The quality indicators of the bread sample prepared from the flour sample ground by dry processing on the proposed equipment showed the superiority of the specific volume of the bread, kernel porosity, ΔН index, bread volume and organoleptic assessment of bread quality over the samples ground on the current equipment used in production enterprises. It was proved that dry processing of the surface of this grain in preparing it for grinding into fine flour is of great technological importance in increasing the technological quality indicators of bakery products.

DEVELOPMENT OF TECHNOLOGY FOR COMPLEX PROCESSING OF GARLIC ONIONS

2026-01-23T12:58:53+05:00

This article presents the results of a study aimed at determining the expected economic efficiency in the production of various biologically active oddes and food additives by complex processing of garlic onions for storage from seasonal periods in unknown periods. During the study, innovative technological parameters of high-efficiency combined (sublimation and convective) drying of garlic onions for complex processing were developed.

DEVELOPMENT OF COMPLEX PROCESSING TECHNOLOGY FOR THE SECONDARY MASS OF WATERMELONS AND ZUCCHINI

2026-01-23T13:33:13+05:00

The main stages of the convective drying process, the effectiveness of the method and the possibilities of energy savings of pumpkin polyz products are analyzed. Opinions have also been expressed on the application of the technology in production conditions, its advantages and disadvantages. Detailed information will be given about the role and importance of this technology in the long-term preservation and quality preservation of zucchini. The article is aimed at contributing to the development of the agrarian industry and looking for ways to improve energy efficiency.

EVALUATION OF ORGANOLEPTIC PROPERTIES OF SOFT DRINKS PREPARED FROM PLANT MATERIALS

2026-01-23T16:32:04+05:00

The article discusses the indicators affecting the quality of soft drinks, namely appearance, transparency, color, aroma, taste, and the amount of sediment on the quality of the product. Methods for determining the organoleptic indicators of drinks according to GOST 28188-89 and GOST ISO 6658-2016, as well as their color indicators, are presented.

RESULTS OF DETERMINATION OF BITUMEN MOVEMENT MODES AT DIFFERENT TEMPERATURES

2026-01-24T14:00:14+05:00

The article presents the results of determining the modes of bitumen movement at various temperatures, the results of reducing the viscosity of construction bitumen grade BNSHK-1 depending on the process temperature, and the results of determining the main parameters of the hydrodynamics of the mixing process (the angular velocity of the mixer is 31.4 rad/s).

RESULTS OF IMPROVING THE CONSTRUCTION OF THE PLATE HEAT EXCHANGE

2026-01-24T14:03:27+05:00

The article examines modern methods of intensifying heat exchange in plate heat exchangers by changing the geometry of channels. The effectiveness of corrugated, chevron, and zigzag structures in reducing flow resistance and increasing the heat transfer coefficient has been substantiated. The peculiarities of the influence of the slope angle of the plate relief on the turbulence of the flow and the formation of stagnant zones are analyzed. Recommendations for choosing geometry are given, taking into account operating conditions in the gas processing industry.

COMPOSITIONAL ANALYSIS OF RAW MATERIALS IN SORBENT PRODUCTION

2026-01-26T21:21:54+05:00

This article presents the results of obtaining an adsorbent based on carbon-containing soot waste through chemical activation using hydrochloric acid and sodium hydroxide. As a result, improvements were achieved in the compositional purity of the material and its sorption properties. Data are presented on the elemental and oxide composition of the waste after chemical activation, which enables a reduction in reagent consumption and the removal of harmful compounds prior to subsequent activation stages. The analytical characteristics of the resulting sorption-active adsorbent are substantiated.

THERMAL TREATMENT OF VARIOUS SAMPLES OF LOW-MOLECULAR-WEIGHT POLYETHYLENE – A BY-PRODUCT OF POLYETHYLENE PRODUCTION

2026-01-27T13:46:34+05:00

A comparative thermal analysis was conducted on three industrial samples of low-molecular-weight polyethylene (LMWPE)—a by-product of polyethylene production—with the aim of determining optimal conditions for carbonization and subsequent activation. The study employed TGA/DSC methods (Ar, 10 °C/min) and laboratory-scale carbonization in a flow-through argon reactor, with gas sampling at specific temperature “windows” followed by GC analysis (TCD + FID). The results indicate that melting occurs in the range of approximately 30–150 °C with less than 1% mass loss; thermal degradation begins at 300–400 °C, with major decomposition occurring between 420–520 °C. The residual mass at 1000 °C was approximately 33% (LMWPE-1), 38% (LMWPE-2), and 53% (LMWPE-3), indicating differences in molecular architecture and suggesting LMWPE-3 as the preferred precursor in terms of carbon yield. Gas evolution trends showed a transition from C₃–C₁₇ olefins/paraffins (300–520 °C) to dominant H₂ and CH₄ evolution at higher temperatures, accompanied by increased aromaticity of the solid residue. It is recommended to limit the upper carbonization temperature to ~500 °C to avoid melting and coalescence, and to employ the 750–820 °C range as the optimal “window” for high-temperature treatment relevant to subsequent alkaline activation.