tech-2023_01(106)

№ 1 (106) январь, 2023 г. Analyzing the obtained results, it can be seen that which makes it possible to reduce the height parameters a change in the current strength from 2000 A to 3500 A of the roughness of hardened surfaces by 2-2.5 times. contributes to a decrease in the height parameters of roughness, and at a current strength of 4000 A, their As can be seen from the obtained data, an increase growth begins. Thus, for parts hardened at high currents, in the processing force from 25N to 100H leads to a it is necessary to introduce finishing methods of pro- decrease in the height parameters of roughness, and cessing. As such methods, diamond smoothing and with a further increase in effort, the height parameters vibropolishing with elastic diamond bars can be used, of roughness increase. References: 1. Machinery Quality: reference book: in 2 Vol. / A.G. Suslov, E.D. Brown, N.A. Vitkevich [et al.]. M.: Mechanical Engineering, 1995. Vol.1. pp. 256. 2. Machinery Quality: reference book: in 2 Vol. / A.G. Suslov, Yu.V. Gulyaev, A.M. Dalsky [et al.]. M.: Mechanical Engineering, 1995. Vol.2. pp. 430. 3. Pronikov A.S. Machinery Reliability. M.: Mechanical Engineering, 1978. pp. 592. 4. Suslov A.G. Surface Layer Quality in Machinery. M.: Mechanical Engineering, 2000. pp. 320. 5. Suslov A.G. Parameter Technological Support of Surface Layer State in Parts. M.: Mechanical Engineering, 1987, pp. 208. 6. Suslov A.G., Dalsky A.M. Scientific Fundamentals of Engineering Technique. M.: Mechanical Engineering, 2002. pp. 684. 7. Suslov A.G., Petreshin D.I., Fedonin O.N., Khandozhko V.A. Automation of quality parameter control of surface layer and machinery operation properties during cutting // Science Intensive Technologies in Mech. Eng. 2019. No.8 (98). pp. 28-36. 8. Technological Support and Operation Properties Increase in Parts and Their Units / A.G. Suslov, V.P. Fyodorov, O.A. Gorlenko [et al.]; under the general editorship of A.G. Suslov. M.: Mechanical Engineering, 2006. pp. 448. 9. Technologist's Reference Book / under the general editorship of A.G. Suslov. M.: Innovation Mechanical Engineer- ing, 2019. pp. 800. 42

№ 1 (106) январь, 2023 г. DOI - 10.32743/UniTech.2023.106.1.14922 RESTORATION OF THE EXTERNAL SURFACES OF MACHINE MECHANISMS BY ELECTROMECHANICAL TREATMENT Almossho Shohiyon Candidate of Technical Sciences, Associate Professor, Institute of Technology and Innovative Management in Kulyab, Republic of Tajikistan, Kulyab E-mail: [email protected] Ziyodullo Obidov Doctor of Chemical Sciences, Professor, Institute of Technology and Innovative Management in Kulyab, Republic of Tajikistan, Kulyab ВОССТАНОВЛЕНИЕ НАРУЖНЫХ ПОВЕРХНОСТЕЙ МЕХАНИЗМОВ МАШИН ЭЛЕКТРОМЕХАНИЧЕСКОЙ ОБРАБОТКОЙ Шохиён Алмосшо Набот канд техн. наук, доц., Институт технологии и инновационного менеджмента в городе Куляб, Республика Таджикистан, г. Куляб Обидов Зиёдулло Рахматович д-р хим. наук, профессор, Институт технологии и инновационного менеджмента в городе Куляб, Республика Таджикистан, г. Куляб ABSTRACT The article discusses the possibility of restoring the outer surfaces of machine mechanisms with electromechanical processing. АННОТАЦИЯ В статье рассматривается возможность восстановления наружных поверхностей механизмов машин электро- механической обработкой. Keywords: outside surface, machine mechanisms, restoration, electromechanical processing. Ключевые слова: наружная поверхность, механизмы машин, восстановление, электромеханическая обработка. ________________________________________________________________________________________________ The practice of launching a series of new engineer- As a working tool in carrying out these experiments, ing products shows that their quality is largely ensured tools were used - rollers made of bronze of the BRKh0.7 by their refinement after production and operational brand and a pseudo-alloy of tungsten carbide with copper. tests. This leads to significant losses of time and material resources from the initial design stage to the launch of The experiments were carried out using ethyl sili- new products in a series. Hence, the accumulated results cate (liquid glass), zapon varnish, and graphite lubricant. of theoretical and experimental studies [1-10] have The additional material (powder) was mixed with the shown that static fatigue strength, contact stiffness, binder in a ratio of 1:1 and applied in a uniform layer on tightness, wear resistance, corrosion resistance of ma- the surface to be restored. chine parts and their connections depend on the quality parameters of the surface layer formed during machin- After surfacing of 3 layers, the restored layer was ing, the physical and mechanical properties of the mate- strengthened by passing the tool in the same modes with rial parts, resulting dimensional accuracy and operating the supply of LC by irrigation into the treatment zone. conditions. The values of the levels of input factors are presented in Table. 1. __________________________ Библиографическое описание: Shohiyon A.N., Obidov Z.R. RESTORATION OF THE EXTERNAL SURFACES OF MACHINE MECHANISMS BY ELECTROMECHANICAL TREATMENT // Universum: технические науки : электрон. научн. журн. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14922

№ 1 (106) январь, 2023 г. Table 1. The values of the levels of input factors for the experiment 23 Factor Xi Factor level X1 Lower (-1) Upper (+1) X2 3000 4000 X3 300 500 0,6 1,0 The experiment was carried out on samples with cylindrical surfaces (with subsequent finishing by dia- three repetitions in each experiment. The experiment mond turning or grinding) by 0.1 - 0.3 mm. planning matrix and the average values of the output fac- tor Y (recovered size) are presented in table. 2. With this recovery method, the magnitude of the current strength has the main influence on the magnitude The results of the studies have shown that electro- of the restored size. This factor will affect the quality of mechanical surfacing of additional material (powder) the adhesion of powder particles to each other and to the applied by coating, bronze and pseudo-alloy rollers base material, as well as the magnitude of the porosity allows you to effectively restore the size of the outer of the coating. Table 2. Matrix of experiment on surfacing with a pseudo-alloy roller № Input factors Output factors, Y experience X1 X2 X3 123 +++ 0,40 0,46 0,49 1 - ++ 0,40 0,54 0,57 2 +-+ 0,50 0,50 0,48 3 - -+ 0,76 0,63 0,56 4 ++ - 0,38 0,43 0,51 5 -+- 0,46 0,49 0,51 6 +- - 0,44 0,44 0,46 7 --- 0,67 0,53 0,56 8 When additional material (powder) is applied to the Electromechanical surfacing of powders can be car- surface to be restored by coating, a coating with a very ried out by preliminary application of coatings and by high porosity is obtained, and sometimes even the de- applying powders with an electromagnet. To obtain a posited layer peels off. This is due to the presence of the more uniform layer, it is recommended to apply a thin so-called \"third body\" - graphite lubricant, which burns layer of the binder on the surface to be restored, and then out during surfacing due to high temperatures in the con- apply additional material by spilling it freely onto the tact zone of the tool and a layer of additional material. coated surface. As the main factors influencing the value of the restored size as a result of the literature analysis, To improve the quality of the restored layer (reduce the following were taken: 1) current (I) - X1 2) tool its porosity and better adhesion to the surface), it is pro- pressing force (P) – X2 3) workpiece rotation speed (V) - posed to get rid of the \"third body\" by applying powder X3 The values of the levels of input factors are presented by free spilling from the hopper. However, with this in table 3. method of applying additional material, there is a very large overrun. The experiment was carried out on samples with three repetitions in each experiment. The number of de- Therefore, to avoid this shortcoming, it is proposed posited layers is 1. After surfacing, the restored layer to use an electromagnetic field to hold the powder in the was hardened by passing a tool with the same modes surfacing zone. To conduct experiments with this and with watering with LC into the treatment zone. method of applying additional material, a special device The experiment planning matrix and the average values was developed and manufactured. of the output factor Y, mm (the value of the restored size), are presented in table 4. Table 3. The values of the levels of input factors for the experiment 23 Factor Xi Factor level X1 Lower (-1) Upper (+1) X2 3000 4000 X3 300 500 0,7 1,0 44

№ 1 (106) январь, 2023 г. Matrix of experiment on surfacing with an electromagnet Table 4. № Input factors Output factors, Y 3 experience X1 X2 X3 12 0,48 +++ 0,46 0,48 0,45 1 - ++ 0,41 0,45 0,51 2 +-+ 0,49 0,52 0,54 3 - -+ 0,54 0,50 0,54 4 ++ - 0,56 0,50 0,71 5 -+- 0,70 0,63 0,53 6 +- - 0,55 0,62 0,61 7 --- 0,61 0,67 8 After the restoration operation, the surfaces of the to the proposed technologies. The results of measurements parts are processed by finishing processing to obtain the of the friction coefficients during the wear of the samples required size. For surfaces restored by electromachining are shown in fig. 1. with additional metal, diamond turning, or semi-finish- ing and fine grinding, is recommended as a finishing Their analysis shows that approximately 2 hours af- treatment. The amount of allowance to be removed is ter the start of testing, the running-in process ends at the 0.1-0.3 mm. level of the microgeometry of the surface layer, i.e. the parameters of the equilibrium surface roughness are The deposited surfaces of the sample were subjected formed. As can be seen from the graphs, the coefficient to grinding and polishing with an endless belt. Experi- of friction with the sample restored by surfacing with mental studies of wear were subjected to initial samples EMT with an electromagnet is somewhat less than that heat-treated and non-heat-treated and restored according of the sample after volumetric hardening. Figure 1. Coefficient of sliding friction for various recovery methods This is due to the porosity of the deposited coating These pores on the working friction surface of the The processing of the results made it possible to de- sample act as oil pockets in which lubricant and wear termine the amount of wear of the samples during products are retained. Sample wear curves are shown the running-in period and the intensity of wear of the in fig. 2. samples during the period of normal wear (table 5). 45

№ 1 (106) январь, 2023 г. Figure 2. Graphs of wear versus time Table 5. Results of wear experiments Processing Wear value h during the running-in Wear intensity I (average values) Class wear method period (L=1269 m), µm during normal wear resistance Non-heat-treated samples 15,2 3,289*10-9 Samples restored by surfacing 1,8 1,07*10-9 III EMO with an electromagnet Samples after bulk hardening 3,4 1,775*10-9 In general, the results of the studies show that elec- results of comparative tests shows that the proposed res- tromechanical surfacing of additional material (powder) toration technologies make it possible to almost double using an electromagnetic field allows you to effectively the wear resistance of the restored part. restore the size of the outer cylindrical surfaces, fol- lowed by grinding by 0.2 - 0.4 mm. An analysis of the References: 1. Pronikov A.S. Machinery Reliability. M.: Mechanical Engineering, 1978. pp. 592. 2. Machinery Quality: reference book: in 2 Vol. / A.G. Suslov, E.D. Brown, N.A. Vitkevich [et al.]. M.: Mechanical Engineering, 1995. Vol.1. pp. 256. 3. Machinery Quality: reference book: in 2 Vol. / A.G. Suslov, Yu.V. Gulyaev, A.M. Dalsky [et al.]. M.: Mechanical Engineering, 1995. Vol.2. pp. 430. 4. Mechanical Engineering: encyclopedia. Vol. IV-3. Machinery Reliability / V.V. Klyuev, V.V. Bolotin, F.R. Sosnin [et al.]; under the general editorship of V.V. Klyuev. M.: Mechanical Engineering, 1998. pp. 592. 5. Suslov A.G. Surface Layer Quality in Machinery. M.: Mechanical Engineering, 2000. pp. 320. 6. Technological Support and Operation Properties Increase in Parts and Their Units / A.G. Suslov, V.P. Fyodorov, O.A. Gorlenko [et al.]; under the general editorship of A.G. Suslov. M.: Mechanical Engineering, 2006. pp. 448. 7. Suslov A.G. Parameter Technological Support of Surface Layer State in Parts. M.: Mechanical Engineering, 1987, pp. 208. 8. Technologist's Reference Book / under the general editorship of A.G. Suslov. M.: Innovation Mechanical Engineering, 2019. pp. 800. 9. Suslov A.G., Dalsky A.M. Scientific Fundamentals of Engineering Technique. M.: Mechanical Engineering, 2002. pp. 684. 10. Suslov A.G., Petreshin D.I., Fedonin O.N., Khandozhko V.A. Automation of quality parameter control of surface layer and machinery operation properties during cutting // Science Intensive Technologies in Mechanical Engineering. 2019. No.8 (98). pp. 28-36. 46

№ 1 (106) январь, 2023 г. PROCESSES AND MACHINES OF AGROENGINEERING SYSTEMS REQUIREMENTS FOR THE QUALITY OF RAW MATERIALS PROCESSED IN THE INDUSTRY Javsurbek Khazratkulov Assistant, Gulistan State University, Republic of Uzbekistan, Gulistan E-mail: [email protected] Abror Jankorazov Assistant, Gulistan State University, Republic of Uzbekistan, Gulistan E-mail: [email protected] Akhmad Nurmukhamedov Assistant, Gulistan State University, Republic of Uzbekistan, Gulistan E-mail: axmad [email protected] Shakir Issakov Assistant, Jizzakh Polytechnic Institute, Republic of Uzbekistan, Jizzakh E-mail: [email protected] ТРЕБОВАНИЯ К КАЧЕСТВУ ПЕРЕРАБАТЫВАЕМОГО В ПРОМЫШЛЕННОСТИ СЫРЬЯ Хазраткулов Джавсурбек Закиржон оглы ассистент, Гулистанский государственный университет, Республика Узбекистан, г. Гулистан Джанкоразов Аброр Мамраджаб оглы ассистент, Гулистанский государственный университет, Республика Узбекистан, г. Гулистан Нурмухамедов Ахмад Анварович ассистент, Гулистанский государственный университет, Республика Узбекистан, г. Гулистан Иссаков Шoкир Аллаберди оглы ассистент, Джизакский политехнический институт, Республика Узбекистан, г. Джизак __________________________ Библиографическое описание: REQUIREMENTS FOR THE QUALITY OF RAW MATERIALS PROCESSED IN THE INDUSTRY // Universum: технические науки : электрон. научн. журн. Khazratkulov J.Z. [и др.]. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14884

№ 1 (106) январь, 2023 г. ABSTRACT Food production and ensuring its safety is one of the important tasks. The requirements for processed raw materials are different from the requirements for vegetables for fresh consumption or preservation. This difference consists primar- ily of an indicator such as external attractiveness. Special attention is paid to the microbiological properties of raw mate- rials. Scientific and research work is being carried out on the requirements for the quality of raw materials and products processed from fruits and vegetables, which are the objects of the vital activity of microorganisms. АННОТАЦИЯ Производство пищевых продуктов и обеспечение их безопасности является одной из важных задач. Требования к переработанному сырью отличаются от требований к овощам для потребления в свежем виде или консервации. Это отличие состоит в первую очередь из такого показателя, как внешняя привлекательность. Особое внимание уделяется микробиологическим свойствам сырья. Ведется научно-исследовательская работа по требованиям к качеству сырья и продуктов переработки из фруктов и овощей, являющихся объектами жизнедеятельности микроорганизмов. Keywords: biological, value, microflora, pathogens, botulus, clostridium, mold, vegetative, aerobic, anaerobic, saprophytic, sterilization. Ключевые слова: биологическое, значение, микрофлора, возбудители, ботулизм, клостридии, плесени, вегетативные, аэробные, анаэробные, сапрофитные, стерилизация. ________________________________________________________________________________________________ Decree of the President of the Republic of Uzbeki- Since the pH value is about 7, bacteria often develop stan No. PF-4947 of February 7, 2017 \"On the Strategy on them. of Actions for Further Development of the Republic of Uzbekistan\", No. PQ-3682 of April 27, 2018 \"Innova- The most common pathogens capable of producing tive Ideas, This dissertation research serves to a certain enterotoxins are Clostridium perfringens, Proteus vul- extent the implementation of the tasks defined in the De- garis, Proteus mirabilis, Bacillus cereus. Enterotoxins cisions on measures to further improve the system of are also produced by pathogens belonging to Klebsiella, practical implementation of technologies and projects enterobacter, Citrobacter, Serratia, Pseudomonas, Aer- and other regulatory legal documents related to this omonas, edwardsiella, Vibrio species. Most enterotox- activity. ins of pathogenic microorganisms are thermolabile. The most dangerous poisoning is botulism. Requirements for raw materials also depend on the type of processing. Raw materials for the production of Botulism (lat. Botulus - sausage) is caused by poi- tomato products should contain a lot of dry matter and a soning with the toxins of botulism bacteria and is char- small amount of waste - seeds, peels, etc. However, in acterized by severe damage to the central and autonomic general, for canning, fruits should be strong and not de- nervous system (paresis and paralysis of tense and formed during heat treatment. The chemical and physi- smooth muscles, sometimes gastroenteritis in the initial cal properties of fruits and vegetables, which are the period) The causative agent of botulism Clostridium objects of vital activity of microorganisms, change. botulinum is widespread in nature, its permanent habitat As a result, the biological value decreases and the tech- is soil. Anaerobes produce spores that are extremely re- nological properties of the product intended for canning sistant to physical and chemical factors. In anaerobic deteriorate. conditions, that is. without the presence of oxygen (in large pieces of meat and fish products, in closed jars), Due to the development of the appropriate microflora, spores multiply and turn into vegetative (living) forms not only the quality of the product deteriorates, but there that produce toxins. are also cases where it can be dangerous for the health (sometimes life) of a person, causing illness or food Botulinum toxin is one of the strongest poisons poisoning. In this case, the risk is related to the fact known in nature, its lethal dose for humans is 0.3 μg. can that pathogenic microorganisms do not always cause be causative agents of botulism. At the same time, the visible damage to the product. disease can occur only with the use of those stored in anaerobic conditions without adequate heat treatment. Pathogenic microorganisms are characterized by the These can be canned goods, especially home-made, fact that they can be the cause of a certain disease - toxin smoked, dried meat and fish products, as well as other infection or toxins that cause human poisoning during products that have conditions for the development of food consumption - intoxication. Major pathogens in vegetative forms of microbes and the formation of toxins. canned food products (tomato products). There is a large number of soil microorganisms on Vegetables - root vegetables (carrots, celery, beets), the surface of tomatoes, including heat-resistant spores onions, garlic, spinach, lettuce, cabbage, tomatoes, and bacteria of the Bacillus and Clostridium families. pumpkins, melons, beans, peas, peppers, etc. - compared Pathogenic microorganisms can enter vegetables from to other plant products, they are low in proteins, carbo- the soil. Escherichia coli, which enters the soil with organic hydrates and fats, except for peas and beans, which are fertilizers and sewage, is often found. Vegetables can also rich in proteins and carbohydrates, but a lot of vitamins, contain worm eggs, which are the cause of outbreaks minerals and fibers. Vegetable spoilage is caused by the if poorly washed vegetables are eaten raw. same pathogens as fruit spoilage, but of vegetables. 48

№ 1 (106) январь, 2023 г. Bacteria and molds play a major role in spoilage of Gray rot - saprophytic fungus Phizopusnigricans vegetables. If the vegetables are damaged during fruit Her. The fruit softens at the site of the lesion, soft watery picking or transportation, the mold process is acceler- mildew covered with a gray flower is formed. The skin ated. Damage to the skin facilitates the penetration of bursts and a sour-smelling juice flows from the fruit. The microorganisms into the product and accelerates the disease spreads easily during transportation and storage, spoilage process. An increase in temperature, ventilation especially at high temperatures (28-32C °). As a preventive and high humidity have a positive effect on the develop- measure, it is necessary to avoid mechanical damage, ment of mold. Due to the mold, the pulp becomes soft maintain the optimal storage regime (ventilation, tem- and unsuitable for canning. The most common: Macro- perature, humidity, etc.). sporiasis is caused by Alternariasolani fungus. Tomato fruits develop depressed round spots, often near the fruit Aqueous (or wet, bacterial) rot is caused by rotting attached to the stalk or at the bruised area. In the future, bacteria. Depressed watery spots appear on the fruits, the spots will be covered with a black flower. The dis- then the pulp is destroyed, it turns into a liquid mass with ease often manifests itself in hot summer, with the pres- an unpleasant smell. The fruit looks like a water bag. ence of fruits with damaged skin, as well as during The disease spreads through wounds on the fruit skin at sudden changes in temperature, during transportation high temperatures. and storage of fruits during sweating. Mosaic and internal fruit necrosis is a viral disease Black rot, or diplodiosis, is caused by the fungi Dip- that manifests itself in the uneven color of tomato fruits lodia pernicious (Plow) Petz and Phoma pernicious during ripening and the formation of dead brown or Plow. The damage starts from the junction to the pedun- brown spots inside the fruit. Affected areas harden and cle; a slightly depressed watery area of light gray color differ sharply from healthy tissues. With a weak lesion, is formed, which gradually increases and turns black. In- internal necrosis can be determined only on cross-section. fection occurs in the field, as well as during transporta- tion and storage of fruits with mechanical damage. Stolbur is a microplasma disease, in which the fruits Preventive measures: avoid mechanical damage to the develop hard, tasteless, there are highly developed fi- skin, observe the hygienic rules of cooking, transportation brous vascular bundles in the form of white threads, and storage. which are clearly visible in the cut areas. The disease is not detected on the surface. Brown rot or late blight, as in potatoes, is caused by the fungus Phytophthora. The fruit tissue turns brown An important preparatory process for processing from the outside and inside, remains firm, and the fruit fruits and vegetables is washing, which removes micro- has an ugly shape. Infection occurs in the field, during organisms and dirt. Water must meet drinking water re- storage, the disease can be spread only by strong sweat- quirements, and sometimes special requirements. ing of the fruit. To prevent the disease, potassium ferti- Bleaching, sterilization, boiling, etc. of raw materials lizers are used, fungicides are sprayed on plants, fruits used for canning. These technological procedures can are harvested early, and breeding varieties resistant to have a positive or negative effect on the nutritional value late blight are developed. of the finished product. References: 1. Decree of the President of the Republic of Uzbekistan dated February 7, 2017 No. PF-4947 \"On the strategy of actions for the further development of the Republic of Uzbekistan\". 2. Dodaev Q.O. Technological calculations in food preservation. Study guide. Tashkent - \"Fan\" - 2003. - 144 pages. 3. Q.H. Majidov, F.B. Ashurov, K.K. Sattorov, N.N. Majidova, F.F. Ashurov, J.Sh. Sultonov Basics of food technology.\" TASIL PRINT \"publisher-2021. 4. Vasiev.M., Dodoev.Q., Isobaev.I., Sapoyeva.Z., Gulyamova.Z., \"Fundamentals of Food Technology\" textbook successor publishing house. Tashkent 2012 y-400b 5. Ismailov T.A., Fatkhullaev A., Rakhimdjonov M.A., Mukhitdinova M.U. Biochemistry of meat and milk. Textbook. Tashkent \"Cholpon\" publishing house, 2014. - 256 p. 6. Issakov Shokir Allaberdioglu Methods of optimization of the fruit drying process. \"Universe: technical science\" 6(99). Moscow 2022. 49

№ 1 (106) январь, 2023 г. TRANSPORT, MINING AND CONSTRUCTION ENGINEERING OPTIMIZATION BASED CONTROL STRATEGIES OF HYBRID ELECTRIC VEHICLES Umidjon Usmanov Master of technical sciences, lecturer in Mechanical and Aerospace Engineering department in Turin Polytechnic University in Tashkent, Republic of Uzbekistan, Tashkent E-mail: [email protected] Karimov Abdulkhay Master’s students in 70711401-Technological processes and automation of production at “Tashkent Institute of Irrigation and Agricultural Mechanization Engineers” National Research University Republic of Uzbekistan, Tashkent E-mail: [email protected] СТРАТЕГИИ УПРАВЛЕНИЯ ГИБРИДНЫМИ ЭЛЕКТРОМОБИЛЯМИ НА ОСНОВЕ ОПТИМИЗАЦИИ Усманов Умиджон Равшанович магистр технических наук, преподаватель кафедры “Технология машиностроения и авиакосмический инжиниринг” в Туринском политехническом университете в г. Ташкенте, Республика Узбекистан, г. Ташкент Каримов Абдулхай Абдусатторович магистрант по специальности 70711401- Автоматизация производства и технологических процессов национального исследовательского университета «Ташкентский институт инженеров ирригации и механизации сельского хозяйства» Республика Узбекистан, г. Ташкент ABSTRACT The increasing number of environmental concerns, raising as a result of greenhouse gas emissions in transportation sector made it almost essential to switch to alternative fuels or electrifying/hybridizing the propulsion system. Hybrid electric vehicle (HEV) is one possible solution to meet the requirements and limits of exhaust pollutant and greenhouse gas emissions. Control strategies or energy management strategy (EMS) ensures the optimal distribution of required power between different power sources of of hybrid vehicles. The proper design of EMS of hybrid vehicles ensures the minimization of both fuel consumption and engine emissions. In this article, various control strategies (EMS) based on optimization are discussed. Both on-line and global optimization strategies of HEV, their potential as well as advantages and disadvantages are provided and thoroughly described. АННОТАЦИЯ Растущее количество экологических проблем, возникающих в результате выбросов парниковых газов в транспортном секторе, сделало практически необходимым переход на альтернативные виды топлива или элек- трификацию/гибридизацию силовой установки. Гибридный электромобиль (ГЭМ) — это одно из возможных решений, позволяющее удовлетворить требования и ограничить выбросы загрязняющих выхлопных газов и пар- никовых газов. Стратегии управления или стратегии управления энергопотреблением (СУЭП) обеспечивают оп- тимальное распределение требуемой мощности между различными источниками питания гибридных транспортных средств. Надлежащая конструкция СУЭП гибридных автомобилей обеспечивает минимизацию как расхода топлива, так и выбросов двигателя. В данной статье обсуждаются различные стратегии управления (СУЭП), основанные на оптимизации. Представлены и подробно описаны как онлайновые, так и глобальные стратегии оптимизации ГАМ, их потенциал, а также преимущества и недостатки. __________________________ Библиографическое описание: Usmanov U., Karimov A. OPTIMIZATION BASED CONTROL STRATEGIES OF HYBRID ELECTRIC VEHICLES // Universum: технические науки : электрон. научн. журн. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14821

№ 1 (106) январь, 2023 г. Keywords: hybrid electric vehicles (HEV), optimization-based energy management strategies (EMS), fuel consumption minimization. Ключевые слова: гибридные автомобили (ГАМ), стратегии управления энергопотреблением (СУЭП), основанный на оптимизации, минимизация расхода топлива. ________________________________________________________________________________________________ 1. Introduction on a number of fundamental rules, including the optimi- zation of both ICE and battery systems. These rules force In order to ensure that the energy provided to the all energy sources to operate at optimum operating line drivetrain is adequate in accordance with the demand or (OOL), i.e., maximum efficiency working point; mini- load power, HEV is studied in terms of the many energy mize the dynamics of ICE as well as optimization of sources that must be correctly controlled. This is be- ON/OFF periods; battery operates in charge-sustaining cause, depending on the situation, electricity could be mode to prolong the battery life and to allow electric motor produced using each energy source, or a combination of (EM) to work efficiency; intensification of regenerative them. At other times, both the battery can be charged, braking based on driver’s action [2]. Overall, we can while internal combustion engine (ICE) can provide classify 5 operating modes of hybrid vehicles: charging power both for charging and propulsion and at other times, while driving, energy regeneration during braking, battery the energy is provided by both the battery and ICE [6]. charging, power starving and batter drive (Figure 1). The broad guidelines for EMS development are founded Figure 1. Operating modes of hybrid vehicles EMSs are divided into two major categories: rule- because the goal of building any EMS is to utilize based strategies and optimization-based strategies. it in practical applications or to serve as a benchmark Rule-based strategies can be further divided into deter- to assess the efficacy of other techniques [3]. ministic and fuzzy-logic rule-based strategies, while op- timization-based strategies are divided into Optimization based control strategies are based on instantaneous (real-time) optimization, global optimization the minimization of cost function by means of analytical and model predictive control (Figure 2). Additionally, or numerical operations [5]. The cost function takes all EMSs are categorized into two groups (offline and into account several parameters. These might be fuel online) based on the usage of real-time implementation consumption, efficiency and emission data. The solution of the problem is optimum either globally or locally 51

№ 1 (106) январь, 2023 г. (only for a given set of input variables). When the driv- by making an assumption that SOC variation in the future ing pattern is known a priori, which is not achievable in is compensated by ICE. practical application, the global optimum solution can be determined. As a result, it cannot be used in actual ������̇ ������������������ = ������̇ ������������������(������������������������, ������������������������) + ������������������������ ⋅ ������̇ ������������������ (1) controllers, although online optimization can be carried out via instantaneous cost function minimization [1]. Where ������̇ ������������������ is equivalent (total) fuel consumption Using instantaneous (real-time) optimization proce- rate; ������̇ ������������������-ICE fuel consumption rate, which depends on dures, the best solution is reached by minimizing the in- engine torque ������������������������ and speed ������������������������; ������������������������-penalty function stantaneous cost function and using the most recent due to battery SOC stabilization; ������̇ ������������������-equivalent bat- input data. The data for the whole driving conditions, tery fuel consumption. pattern, and time history of other factors is needed for global optimization strategies. Average efficiencies of power units, fuel consumption rate and mean power are required to calculate the equiv- 2. Equivalent consumption minimization strategy alent fuel consumption of batteries [12]. The equivalent fuel consumption is calculated using ECMS based on This technique was first proposed by Paganelli et al. the online measurements of the quantities on board and [4] and aims at minimization of cost function, which is the current system condition. In order to obtain an optimal equivalent fuel consumption. The idea is that electrical solution, no prior knowledge of driving behavior is nec- energy can be equivalently converted to fuel consumption. essary, and can be applied online. It reduces a global The total fuel consumption, which is the cost function is optimization problem into an instantaneous minimization the sum of direct consumption, which comes from ICE problem and provides the optimum solution at each time and equivalent battery fuel consumption. The calculation instant [13]. of equivalent fuel consumption of batteries is performed Figure 2. Classification of control strategies of HEV 3. Neural networks output data by learning from the previous experience. Neural networks are trained by constructing probability- A computer technology known as an artificial neu- weighted associations between the two that are then ral network (ANN) can replicate a biological brain and stored within the net's data structure while processing is intended to carry out a given task without actually samples that each have a known \"input\" and \"output\" [4]. knowing the physical model of a system. ANN creates 52

№ 1 (106) январь, 2023 г. One must choose from a list of approved models and ������̇(������) = −������������(������(������), ������(������), ������(������), ������) (3) related methodologies for ANN training. The network's processed output and the desired output are then frequently Where ������������ is differential of the Hamiltonian function. compared using an example as a starting point. The The adjoint function is a Lagrange multiplier that in- network then adjusts its weighted associations utilizing forms the optimization problem of the state equation a learning technique and this error value. The neural net- constraint. Hamiltonian function is minimized by z(t), work will produce output that is increasingly comparable corresponding optimal state u(t) and adjoint λ(t) according to the goal output as modifications are made over time [14]. to the Pontryagin’s minimum principle. These modifications can be made a sufficient number of times before the training can be stopped under certain 6. Linear programming conditions. There are three or more interconnected lay- ers in an ANN. Neurons in the input layer make up the When the requirements are expressed as linear rela- first layer. These neurons transmit information to hidden tionships in a mathematical model, linear programming layers, which then transmit the final output information (LP) is a special case of mathematical optimization that to the final output layer [15]. looks for the optimal solution. Relationships based on linear equality and inequality express the limitations, 4. Particle swarm optimization and linear relationships are used to characterize the objec- tive function. Linear programming problems are a major A computer heuristic technique known as particle class of optimization problems because they require swarm optimization (PSO) iteratively improves the pre- the location of the feasible region and optimization of dicted solution to optimize the objective function. The the solution to have the highest or lowest value of the movement of particles (also known as the population or function [4]. Different approaches, such as the graphical candidate solution) inside the search space is controlled method, the simplex method, or the use of additional by mathematical relationships over their position and tools, can be used to tackle LP problems. Some assump- velocity [5]. In PSO, particles use both their own best- tions must be taken into account while using this tech- known positions and the positions of the entire swarm to nique: expression of constraints in quantitative terms; move through a search space. The improved placements, presence of linear relationships between the constraints once determined, will control the motion of the swarm and objective function; optimization of linear (objective) particles. These approaches should cause the swarm to function [4]. The components of this technique are objec- navigate toward the best solution. Repeating the proce- tive function, constraints, decision variables, data. The for- dure, however, does not guarantee a positive result. PSO mulation of LP method is is a metaheuristic approach since it has a broad search space for potential solutions and makes few to no as- ������(������1, ������2) = ������1������1 + ������2������2 (4) sumptions about the problem it is trying to solve. PSO does not, however, guarantee the best result [2]. More par- The constraints are ticular, PSO does not use the gradient of the improved problem, which means that, in contrast to conventional ������ ⋅ ������ ≤ ������ (5) optimization approaches, PSO does not need that the im- proved problem be differentiable [1]. In reality, improving fuel economy is a convex nonlin- ear optimization problem that is ultimately approximated 5. Pontryagin’s minimum principle by linear programming. Linear programming is mainly used in series HEVs to increase fuel efficiency. A global It is a generalization of Euler-Lagrange equations, optimal solution is the outcome of the LP optimization that takes into account constraints on the control input. method. It provides a control for a dynamical system to be takes from one state to another when the constraints for a state 7. Dynamic programming or input control are present. It claims that in order to solve the two-point boundary value problem known as Dynamic programming (DP) is an optimization the \"Hamiltonian system,\" which is a two-point optimum technique that transforms a complex problem into a control problem, both the optimal state trajectory and series of simpler ones. A broad framework for studying any optimal control are required [2]. a wide variety of problem types is provided by dynamic programming. This framework allows for the use of a Control Hamiltonian function H can be constructed range of optimization strategies to address specific issues by appending the state equation to the integrand L using with a more general formulation [12]. It has the benefit the Lagrange multipliers, λ(t) follows [2]: of being applicable to problems with constraints and without constraints as well as linear and nonlinear systems. ������(������(������), ������(������), ������(������), ������) It should be emphasized that the overall problem depends = ������(������(������), ������(������), ������) on the optimal solution to its subproblems. The appropriate + ������������(������)������(������(������), ������(������), ������) (2) division of optimization problems into several levels, each of which is solved one level at a time is a crucial Where ������(������) is the optimal control, and ������(������) is the component of DP [11]. corresponding optimal state. Then, there exists a continu- ous function λ, called adjoint function, which is the solution However, the main disadvantage of this technique of the adjoint equation. is the \"curse of dimensionality\", which increases the 53

№ 1 (106) январь, 2023 г. computational difficulty and restricts the use of the method Heuristic search algorithms are used to optimise to complex systems. The DP algorithm cannot be used the search issues in the case of genetic algorithms (GA). in real time because it requires prior knowledge of the The underlying idea of GA is derived from Darvin's driving cycle. Its outputs, however, can be utilized to theory of evolution. As a beginning point, a preliminary design and fine-tune real controllers. set of answers from a certain population should be offered. The replies from one population are used depending on 8. Pseudo-spectral method their capacity to produce new populations. Since the best solutions have a higher likelihood of developing than Combining theoretical and computational approaches, the worst ones, the process is kept going until the desired pseudo-spectral optimization technology addresses opti- state is achieved. mization issues. Pseudospectral optimal control is a term that covers a variety of ideas [5]. Among these are the 10. Model predictive control Ross-Fahroo pseudospectral method, the Gauss pseudo- spectral method, the Legendre pseudospectral method, Model predictive control (MPC) uses a model to the flat pseudospectral method, the Bellman pseudo- predict the future outputs based on previous and current spectral approach, and many others [6]. To address an values. The models, that are used in MPC describe the optimal control problem, it is necessary to approximate behaviour of complex and simple dynamic systems. the integration in the cost function, the differential equation MPC models forecast the change in the modeled sys- of the control system, and the state-control constraints [3]. tem’s dependent variables that will result from changes The best approximation technique should be effective in the independent variables [6]. Future changes in the for all three approximate objectives. It's possible that a dependent variables are calculated using MPC using the method, such as an efficient ODE solver, that works well current plant data, the present dynamic state of the pro- for one of them may not work well for the other two. cess, the MPC models, and the process variable targets The best option for satisfying these requirements is to and limits. These adjustments are calculated to respect employ PS methods because they are efficient at approx- limitations on both the independent and dependent varia- imating all three mathematical objects [15]. A group bles and keep the dependent variables around their de- of properly selected quadrature nodes are utilized in a sired values. When a subsequent modification is pseudospectral approach to approximate the continuous required, the MPC normally repeats the calculation after functions. The quadrature nodes are determined by the sending out the first change for each independent varia- related orthogonal polynomial basis used for the approx- ble to be applied [3]. Several strategies can be utilized imation. In PS optimal control, Legendre and Chebyshev when linear models are insufficiently accurate to capture polynomials are widely used. the true process nonlinearities. To lessen nonlinearity, the process variables may occasionally be changed prior 9. Stochastic control strategy to and/or following the linear MPC model. Nonlinear MPC, which employs a nonlinear model directly in the The stochastic approach provides a framework for control application, may control the process. The main modelling optimization problems that include uncertainty. advantage of MPC is that it enables timeslot optimization This approach is used to formulate an infinite-horizon while taking future timeslots into consideration. This is stochastic dynamic optimization problem. A stochastic accomplished by repeatedly optimizing a finite time Markov process is used to model the driver's power horizon while only using the current time slot for imple- request. The Markov driver model generates the proba- mentation. bility distribution for the anticipated future power re- quests and predicts what they will be. This prediction 11. Conclusion does not depend on the decisions made in the past [5]. The best control strategy is then chosen using stochastic According to earlier research, EMS is a crucial com- dynamic programming. The derived control law, which ponent of a hybrid vehicle. The EMS is the controller takes the form of a stationary full-state feedback, is directly that decides which energy source will supply the required implementable. It is found that the derived SDP control amount of power for the particular mode of operation. strategy outperforms a suboptimal rule-based control Since most EMS types ignore battery deterioration, approach learned from deterministic DP findings. The EMS optimization for a HEV is essential and required. stochastic technique optimizes the control strategy over This article has analyzed and addressed earlier investi- a family of diverse driving cycles as opposed to deter- gations into the improvement of HEV EMS. Despite the ministic optimization over a single DC [1]. Stochastic fact that numerous research on EMS optimization have control strategy is further divided into stochastic dynamic been presented, the most of them are restricted to simu- programming and genetic algorithms. lation and do not include real-time applications or ex- perimental setup validation. As a result, an experimental Random variables are used to represent the optimiza- setup or real-time application must be used to validate tion problem in stochastic dynamic programming (SDP). the optimization of the EMS simulation. State or decision functions are formulated in terms of probability functions in SDP. This demands a lot of computational work. 54

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№ 1 (106) январь, 2023 г. TECHNOLOGY OF MATERIALS AND PRODUCTS OF THE TEXTILE AND LIGHT INDUSTRY DOI - 10.32743/UniTech.2023.106.1.14928 SCIENTIFIC AND METHODOLOGICAL BASES FOR DESIGNING SPECIAL SHOE FOR HIGH TEMPERATURES Temur Pulatov Assistant Tashkent Institute of Textile and Light Industry Republic of Uzbekistan, Tashkent E-mail: [email protected] Dilnoza Pazilova PhD, assistant professor Tashkent Institute of Textile and Light Industry Republic of Uzbekistan, Tashkent E-mail: [email protected] Nodir Mirzaev DSc professor Tashkent Institute of Textile and Light Industry Republic of Uzbekistan, Tashkent E-mail: [email protected] Shaxobiddin Kodirov Assistant Jizzakh Polytechnic Institute Republic of Uzbekistan, Jizzakh E-mail: [email protected] НАУЧНО-МЕТОДОЛОГИЧЕСКИЕ ОСНОВЫ ПРОЕКТИРОВАНИЯ СПЕЦОБУВИ ДЛЯ ПОВЫШЕННЫХ ТЕМПЕРАТУР Пулатов Темур Анвар угли ассистент, Ташкентский институт текстильной и легкой промышленности Республика Узбекистан, г. Ташкент Пазилова Дилноза Зиёвутдиновна PhD, доцент, Ташкентский институт текстильной и легкой промышленности Республика Узбекистан, г. Ташкент Мирзаев Нодир Баходирович DSc профессор, Ташкентский институт текстильной и легкой промышленности Республика Узбекистан, г. Ташкент Кодиров Шахобиддин Урол угли ассистент, Джизакский политехнический институт Республика Узбекистан, г. Джизак __________________________ Библиографическое описание: SCIENTIFIC AND METHODOLOGICAL BASES FOR DESIGNING SPECIAL SHOE FOR HIGH TEMPERATURES // Universum: технические науки : электрон. научн. журн. Pulatov T. [и др.]. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14928

№ 1 (106) январь, 2023 г. ABSTRACT The article studies the influence of harmful factors on a person during firefighting, the requirements for indicators of the purpose of personal protective equipment for the firefighter's legs and the application of a scientific and methodological approach to the design of special-purpose footwear for firefighters. АННОТАЦИЯ В статье изучены влияния вредных факторов на человека при пожаротушении, требования, предъявляемые к показателям назначения средства индивидуальной защиты ног пожарного, и применение научно-методологический подход к проектированию обуви специального назначения для пожарных. Keywords: shoes, lining, thermal insulation, material, leather, waterproof, density, fabric, factor. Ключевые слова: обувь, подкладка, термоизоляцион, материал, кожа, водонепроницаемость, плотность, ткань, фактор. ________________________________________________________________________________________________ The sustainable pace of economic development of The process of burning combustible substances and our Republic largely depends on the state of working materials in a fire is a fast-flowing chemical oxidation conditions in the workplace. Especially priority in this reaction and physical phenomena, without which com- direction has recently become the issue of providing bustion is impossible, accompanied by the release of workers with overalls, special footwear and other means heat and the glow of hot combustion products with the of individual and collective protection. formation of a laminar or turbulent diffusion flame. Combustion leads to the release of heat products, an in- The share of research on the creation of multicompo- crease in the surface temperature and an increase in the nent and functional materials through purposeful changes rate of oxidation in the zone of its chemical reaction. Un- and regulation of the microstructure is increasing in the der the influence of heat released in the combustion world. The creation of a waste-free, resource-saving, zone, heating, destruction, evaporation and ignition of environmentally friendly innovative technology of the following sections of combustible substances and multilayer materials based on natural and synthetic fi- materials occur. This process is accompanied by gas and brous raw materials is of particular importance. Such heat transfer, which are called general phenomena char- compositions are widely used in the production of 50% acteristic of any fire, regardless of its size and location. of modern footwear, fur products, 60% of leather goods, General phenomena can lead to the manifestation of par- in particular, in the production of thermal insulation ticular ones: explosions, deformation and collapse of lining materials for shoes [1]. technological apparatus and installations, building struc- tures, boiling up or ejection of oil products from tanks, A fire is an open thermodynamic system that ex- etc. (picture 1). changes substances and energy with the environment. The main phenomena accompanying a fire are the processes of combustion, gas and heat exchange, which change in time and space. Figure 1. Mass and heat transfer on fire: a - heat transfer in a fire; b - zones on fire: 1 - combustion zone; 2 - zone of thermal influence; 3 - smoke zone Often, the combustion temperature of some materials loss of consciousness, and even death (Table 1). Therefore, in a fire reaches 1000° C. Practice shows that at a tem- when choosing the degree of protection of a firefighter perature equal to 80-100°C in dry air and at 50-60°C to eliminate the combustion process, it is necessary to take into account the harmful environmental factors in humid air, a person without special thermal protection that constitute a potential hazard to human health [1]. can stay only a few minutes. A higher temperature or prolonged stay in this zone leads to burns, heat stroke, 57

№ 1 (106) январь, 2023 г. Table 1. Conditions for a person to stay in a fire depending on the heat flux density № Heat flux density, Permissible time Required protection The degree of thermal exposure kW/m2 of stay of people, min of people to human skin 1 3,0 Not limited No protection No pain sensations 2 4,2 Not limited In combat clothes and hel- Unbearable pain after 20 seconds 3 7,0 5 mets with protective glass 4 8,5 5 5 10,5 5 Same Unbearable sensations that occur 6 14,0 5 instantly 7 85,0 1 In combat clothes soaked with water and in helmets Burns after 20 s with protective glass The same, but under the protection of sprayed water Instant burns curtains In heat-reflecting suits pro- tected by water jets and Same curtains The same, but with per- Same sonal protective equipment The safe time for people to stay in the heat-affected The presence of personnel in the danger zone is initially zone is determined by the length of combat work, which limited to 10-15 minutes, and the period for restoring the excludes dangerous overheating of the human body. thermal state of the body to the initial level is at least 1 hour. Figure 2. Scheme of the influence of harmful factors on a person during fire fighting 58

№ 1 (106) январь, 2023 г. When performing combat operations to extinguish temperature (heat resistance, reflective properties, etc.). fires and eliminate the consequences of accidents, In addition, from an economic point of view, the material a firefighter experiences the maximum possible impact must withstand the specified service life and have a low of harmful factors. Standard GOST 12.0.003-74 “Haz- cost. ardous and harmful production factors. Classification” the following groups of relevant factors are established, The choice of materials for the manufacture of foot- which are presented in Figure 2 [2-3]. wear for special purposes is significantly limited by the relevant regulatory and technical documentation. Ac- Proper assessment of the risk to which a firefighter cording to GOST 53265-2009 \"Personal protective is exposed during the performance of basic duties requires equipment for firefighter's feet\", the requirements the use of special-purpose footwear with an appropriate presented in Table 2 are regulated for special footwear level of thermal insulation properties. for firefighters. The materials used for footwear must meet both The requirements for the indications for the ap- the generally recognized requirements for footwear pointment of personal protective equipment for the legs (technological, hygienic, aesthetic), and special, due of a firefighter SIZNP must correspond to the values to the specific operating conditions in the field of high \\u200b\\u200bgiven in table 2. Table 2. Requirements for the indicators of the purpose of personal protective equipment for the legs of a firefighter Name of indicator Meaning indicator Method tests 1 Toe resistance to ambient temperature 200°C, s, not less than 300 By 7.2 2 Toe resistance to heat flow 5.0 kW/m2, s, not less than 300 By 7.3 3 Resistance of a package of sole materials to a puncture between 1200 According to GOST reefs, N, not less than 20 12.4.177 4 Internal safe clearance in the fore part at impact energy (200 ± 5) J, According to GOST mm, not less than 12.4.151, GOST 12.4.162 5 Flexibility 29 According to GOST 9718 - for leather SIZNP, N, no more 29 According to GOST - for rubber SIZNP, N/cm, no more 12.4.162 6 SIZNP height, mm, not less than: 225 By [1] - for leather PPE 225 According to GOST - for rubber SIZNP 12.4.072 7 Mass of a half-pair of SIZNP, kg, no more 1,6 By 7.4 8 Mass of a half-pair of supplementary insulation, kg, not more than 0,2 By 7.4 9 Reef depth, mm, not less than: 1,5 By 7.5 - soles and heels for leather SIZNP 4,0 By 7.5 - soles for rubber SIZNP 9,0 By 7.5 - heels for rubber SIZNP 10 Waterproof: 60 By 7.6 - for leather SIZNP, min, not less than Waterproof According to GOST 12.4.072 - for rubber SIZNP When selecting criteria that determine the require- • all fittings and parts used (buckles for adjusting ments for the design of special-purpose footwear that the width of the shaft, nails, etc.) must be made of anti- protects against high temperatures, special attention corrosion materials or have an anti-corrosion coating; should be paid to the type of footwear that provides pro- tection from the highest possible level of harmful fac- • special footwear should not interfere with dressing tors. According to [4], the following requirements for on alarm for the standard time of all types of combat the design of shoes for this purpose are regulated: clothing; • safety shoes should be made from 245 to 307 sizes; • the depth of the reef of the sole and heel must • an internal safe gap in the toe of safety shoes with be at least 1 mm. an impact energy of (200 + 5) J must be at least 20 mm; • the mass of a half-pair of safety shoes size 270 At the same time, the priority factor that has a neg- should not exceed 1600 g; ative impact on the human body under conditions of • the height of safety shoes should be no more than high thermal load is extreme temperature (> 200°C), 345 mm; which causes increased sweating from the surface of the • the design of leather safety shoes should ensure foot. In this case, special footwear as a means of personal ease of dressing and fixation on the lower leg; protection is designed to prevent the effects of heat from • the color of safety shoes must be black; the outside, on the one hand, and provide an optimal microclimate inside the shoe, on the other. 59

№ 1 (106) январь, 2023 г. Table 3. Requirements for the physical and mechanical properties of leather personal protective equipment for firefighter's legs Name of indicator Meaning indicator Test method 1 Sole fastening strength, N/cm, not less than: 150 According to GOST 9134 - in the gel part 250 According to GOST 9134 - at the toe 70 According to GOST 9292 - with glue method 900 According to GOST 9136 2 Heel fastening strength, N, not less than 200 According to GOST 9290 240 According to GOST 9290 3 Fastening strength of blank seams, N/cm, not less than: - with two lines Minus 40 According to GOST 7912 - more than two lines 4 Temperature limit of brittleness of the sole, °С, not higher The properties of rubber SIZNP should correspond Rubber PPE should have impact protection in the to the values given in table 3. rear of the foot, shin and ankle (see Table 4, indicator 8). Table 4. Properties of firefighter's rubber leg protection Name of indicator Meaning indicator Test method 1 Temperature limit of brittleness of rubber, °С, not higher Minus 40 According to GOST 7912 2 Load at rupture of rubber, N, not less than 130 According to GOST 270 3 Change in the volume of a rubber sample after exposure to a mixture 100 According to GOST 9.030 of isooctane and toluene in a ratio of 7:3 for (70 ± 2) h, %, not more According to GOST 9.030 2,0 4 Chemical resistance of rubber at a temperature of (23 ± 2) ° C 0,7 to exposure for (24 ± 1) h of 40% hydrochloric acid solution or 40% sulfuric acid solution, or 35% sodium hydroxide solution: - sample mass increase, %, no more - coefficient of load change at rupture of specimens, not less than 5 Coefficient of change in load at break after aging of rubber 0,7 According to GOST 9.024 in air at a temperature of (100 ± 3) °C for (24 ± 1) h, not less than 6 Oxygen index of rubber, %, not less than 26 According to GOST 12.1.044 7 Resistance of rubber SIZNP to open flame, s, not less than 30 By 7.7 8 Impact energy absorption, %, not less than 60 According to GOST 12.4.162 The range of domestic and foreign manufacturers of footwear for this purpose is shown in Figure 3. Figure 3. Model range of footwear assortment for firefighters 60

№ 1 (106) январь, 2023 г. A significant disadvantage of these products in an Shoes are made by direct casting of raw rubber com- environment with extremely high temperatures can be pounds. Top model of traditional design, i.e. with adjust- considered the lack of the possibility of timely drying. able lace-up berets. On each beret there are 8 blocks and 3 hooks. Rigid fixation of the shin with shoes will reduce In order to eliminate this drawback, a shoe model injuries to the feet of firefighters when performing com- was developed that, due to the design, can provide quick bat operations to extinguish fires and facilitate move- drying in natural or artificial conditions. ment on inclined and wet surfaces (Fig. 4). The proposed boots are made with high berets 345 mm high in accordance with [4]. аб Figure 4. Boots for firefighters Upper material - chrome leather 2.0 - 2.2 mm thick smaller than a drop of water, so they do not allow mois- with water-repellent impregnation. Lining - membrane ture to enter the boot, and at the same time, 700 times more fabric \"СROSSTECH\" [5]. than a vapor molecule, due to which evaporation is re- moved from the boot, which allows the foot to \"breathe\" In boots made of fire-resistant chloroprene rubber and stay dry. The presence of membrane fabric in shoes produced by CJSC Faraday Companies (Russia), a metal provides good air circulation and microclimate inside anti-puncture insole, a protective metal toe cap and a fire the boot. Membrane fabrics are not thermal insulators. and oil and petrol resistant chloroprene sole are used to increase the protective properties of footwear. Lining In addition, the Deaf valve model prevents water, package of materials from laminated GORE-TEX mem- small stones and sand from entering the inside of the brane fabric and insulation. Boots are designed for use boot. In the middle part of the figured valve, a leather at ambient temperatures from minus 400C to plus 400C. detail is sewn - an amplifier that protects the leg from The mass of a pair of boots 270 (42) size is not more mechanical influences. than 3200 g. Boots are equipped with special stockings made of natural or artificial fur, cloth or baize, designed The figured elongated soft cuff provides a comfort- to protect against convective heat and adverse climatic able fit to the lower leg and improves the appearance of influences. the boot. The figured cuff serves for protection of a shin from injuries and convenience at operation. The main distinguishing characteristics of modern special footwear for firefighters: the presence in the In the manufacture of footwear for protection against footwear of an impact-resistant metal toe cap that pro- the cold, they tend to use designs with fewer seams to tects the toe of the foot from impacts with a force of 200 J; preserve the heat-shielding properties of the product [7]. hard backs, giving shape stability to the heel of the shoe; metal insole protects the foot from cuts and punctures; Thus, the creation of high-quality thermal footwear heat-resistant sole withstands temperatures from - 40 to is based on a set of requirements for various characteristics + 250 0С; side loops for easy and quick donning; as a that regulate the degree of compliance with the conditions lining, a membrane breathable material was used, which of the type of activity (tactical-technical, ergonomic, allows the skin of the foot to \"breathe\" and eliminates hygienic and aesthetic requirements). Achieving the the \"greenhouse\" effect in summer; removable insoles required level of the above indicators in most cases is of a porous structure, evenly distributing the load on the ensured through the use of appropriate raw materials, foot, which contributes to less fatigue of the legs [6]. fittings, etc. The main properties of the material are water Taking into account the fact that primarily protec- resistance and wear resistance. It owes these properties tive properties are applied to heat-insulating shoes, the to the membrane, which is a very thin fluoroplastic film. considered model should be checked for compliance It has such a structure that its pores are 20,000 times with the quality indicators declared by NBP158-97. A preliminary analysis of the determination of the heat-shielding efficiency of safety shoes can be carried out on a mathematical model of heat transfer in the toe part 61

№ 1 (106) январь, 2023 г. of the shoe, which allows you to conduct a numerical area - the toe of the shoe - is shown in Figure 5 (expla- experiment with various combinations of model param- nations for the positions of the figure 5 are presented eters. Thus, it becomes possible to reduce numerous in table 5). costly physical tests. The geometric model of the study Figure 5. Geometric model of the toe of the firefighter's safety shoes: a - longitudinal section of the shoe; b - a fragment of the longitudinal section of safety shoes in the toe part Table 5. Thermophysical properties of materials of the system \"human foot - safety shoes - environment\" № Layer name Layer Density, Heat capacity, Thermal thickness, m kg/m2 kJ/(kg °С) conductivity, 1 Integumentary tissues of the foot 2 Cotton the cloth 1 1093 3600 (W/m °С) 3 Air 1 2000 1380 0,389 4 Pigskin lining 20 1,205 1000 5 Nitroiskozha-T 1 892 1557 0,05 6 Heat-resistant yuft 1 800 1500 2 910 1550 0,034 0,069 0,082 0,073 The processes of heat transfer in shoes are described T0 = Твнут, Тн = Твнеш by the equation of non-stationary heat conduction [5], which in the case under consideration has the form In a spherical coordinate system, equation (1) takes the following form ρc ∂T = div(λ·gradT) (1) ∂T 1 ∂ (λr2· ∂T) ∂t ∂t r2 ∂r ρc = ∂t (2) We accept that the temperature inside the toe of the shoe is a function of radius r and time t, that is, T = T (r, t); the temperature at the point 0 - T0 is known (the temper- Applying the finite difference method, we obtain for ature of the human body, equal to 30 °C). the i-th grid node: To obtain a unique solution to this equation, it is ������������ ������������ ������������������+1 − ������������������ = necessary to supplement it with initial conditions Т(r,0) ∆������ and conditions on the boundary 62

№ 1 (106) январь, 2023 г. ������������+������ (������������+∆������������)������·(������������������+∆������������−������������������)−������������(������������+∆������������)������·(������������������−∆������������������������−������) ������������������ = ������(������������, ������������); ������������������ = ������������������������������������������������������ (������������); ���������2��� ·∆������ ������0������ = ������������������������������������������������; ������������0 = ������������������������������������ (������������) (3) Total calculation time tcommon = 360 sek. At step where i = 1,2,...,n — 1; j = 0,1,2,...,m; ∆t - time step ∆t =30 sek, m =12. t (∆t = tj+1 - tj); ∆r - step by coordinate r (∆r = ri+1 — ri); λi, ρi и ci - values of thermal conductivity, density and Let us solve equation (3) with respect to ������������������+1 heat capacity of a layer of material enclosed between nodes (i-1) and i. ������������������+1 = ������������������ + ∆������ [λ������+1 (������������ + ∆������)2 ·(���������������+��� 1 − ������������������ ) − λ������ (������������ − ∆������)2 ∙ (������������������ − ���������������−��� 1)] (4) ���������������������������������2��� ∆������2 2 2 где i = 1,2,...,n -1; j = 0,1,2,...,m. The system of relations (4) makes it possible to find The calculation made using a mathematical model made it possible to obtain graphs of the dependence the temperature at all nodes of the grid at the moment of of heat transfer processes on time, shown in Figure 6. time t1 = ∆t, t2 = 2∆t, tj = j∆t, up to tcom= 360 с. Figure 6. Dependence of the temperature distribution on the surface of the layers of the system \"human foot - special footwear - environment\" on the time of exposure to high thermal load: integumentary tissues of the foot; sek, internal details of the top of the shoe; В-В - frame parts of the upper of the shoe, outer parts of the shoe upper Analyzing the data of the presented graphs, one case, the effect of heat flow in this case was not taken should keep in mind the following provision of NPB into account. 158-97, that the arithmetic mean of the temperature on In order to confirm the results obtained from the re- the inner surface of the composition of the layers of spe- sults of mathematical modeling, a series of experiments cial footwear should not exceed 50°C for at least 5 was carried out to obtain numerical values of the tem- minutes. The most informative in this case is the heat perature of the shoe space. The temperature-sensitive transfer graph of the internal parts of the upper of the sensor was fixed on the internal parts in the toe before shoe. The permissible temperature limit is reached after placing the safety shoes in a heating cabinet with a con- 50 sec. from the moment of exposure to only an external stantly maintained temperature of 200°C. Fixing the results temperature of 200 ° C, which does not meet the require- of the measuring device every 10 seconds. made it possible ments of regulatory and technical documentation. In this to confirm the numerical indicators of mathematical calculations (Fig. 7). 63

№ 1 (106) январь, 2023 г. Figure 7. Graph of the dependence of the temperature on the inner surface of the composition of the layers of special footwear on the external temperature Thus, the application of a scientific and methodo- However, the developed design of the model provides logical approach to the design of special-purpose foot- an improvement in hygienic properties by improving the wear for firefighters made it possible to reveal that the quality of care for the model without losing priority choice of a package of materials is the dominant factor. protective indicators. References 1. Ўзбекистон Республикаси Президентининг “Чарм-пойабзал ва мўйначилик соҳаларини ривожлантириш ва экспорт салоҳиятини оширишни янада рағбатлантириш чора-тадбирлари тўғрисида”ги ПҚ-3693-сон қарори. Тошкент ш., 2018 йил 3 май. 2. ГОСТ 28507-90 Обувь специальная кожаная для защиты от механических воздействий. Общие технические условия. 3. ГОСТ 12.0.003-74 «Опасные и вредные производственные факторы. Классификация». 4. Шарапа Т.П., Автореферат диссертации \"Разработка и исследование новых конструкций и технологии спецобуви для защиты от повышенных температур\". 5. Maksudova U.M., Rafikov A.S., Mirzaev N.B., Theoretical foundations of obtaining lining composite materials/ International Jornal of Advanced Research in Science, Engineering and Technology/ vol. 5, Issue 10, October 2018. P. 6994-6996. 6. U.M. Maksudova, N.B. Mirzaev, D.Z. Pazilova, Sh.Sh. Sheraliev, Analysis of innovative technologies in the manufacture of composite lining materials/ International Jornal of Advanced Research in Science, Engineering and Technology/ vol. 5, Issue 10, October 2018. P. 7013-7015. 7. Rafikov A., Alimkhanova, S. Mirzaev, N. Multilayer nonwoven lining materials made of wool and cotton for clothing and footwear Journal of Industrial Textiles this link is disabled, 2022, 51(4), pp. 6173S–6194S 8. Спиридонов А.А. Планирование эксперимента при исследовании технологических процессов / – Москва. “Машиностроение”. 1981. С. 184. 64

№ 1 (106) январь, 2023 г. FOOD TECHNOLOGY ANALYSIS OF RESEARCH ON PRODUCTION OF OPTIMAL AND ENRICHED FATTY ACID OILS Khudoyar Aralov Associate professor, Jizzakh Polytechnic Institute, Republic of Uzbekistan, Jizzakh E-mail: [email protected] Shokir Issakov Assistant, Jizzakh Polytechnic Institute, Republic of Uzbekistan, Jizzakh E-mail: [email protected] Azizbek Kilichov Assistant, Jizzakh Polytechnic Institute, Republic of Uzbekistan, Jizzakh E-mail: [email protected] АНАЛИЗ ИССЛЕДОВАНИЙ ПО ПРОИЗВОДСТВУ ОПТИМАЛЬНЫХ И ОБОГАЩЕННЫХ ЖИРНОКИСЛОТНЫХ МАСЕЛ Аралов Худояр Мусакулович доц., Джизакский политехнический институт, Республика Узбекистан, г. Джизак Иссаков Шoкир Аллабердиоглы ассистент, Джизакский политехнический институт, Республика Узбекистан, г. Джизак Киличов Азизбек Абдуганиоглы ассистент, Джизакский политехнический институт, Республика Узбекистан, г. Джизак ABSTRACT Today, as a result of research carried out by local and foreign researchers, lipids are not only effective energy reserves with high satiety, but also metabolically active substances depending on the balance of complex physiological active substances in the fatty acid content of edible oil. АННОТАЦИЯ На сегодняшний день в результате исследований, проведенных отечественными и зарубежными исследова- телями, липиды являются не только эффективными энергетическими резервами с высокой сытостью, но и мета- болически активными веществами, зависящими от баланса сложных физиологически активных веществ в жирнокислотном составе пищевого масла. Keywords: triglyceride, oleic acid, palmitic acid, myristin, arachin, lignocerin, coupling. Ключевые слова: триглицерид, олеиновая кислота, пальмитиновая кислота, миристин, арахин, лигноцерин, сочетание. ________________________________________________________________________________________________ __________________________ Библиографическое описание: Aralov K.M., Issakov S.A., Kilichov A.A. ANALYSIS OF RESEARCH ON PRODUCTION OF OPTIMAL AND ENRICHED FATTY ACID OILS // Universum: технические науки : электрон. научн. журн. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14902

№ 1 (106) январь, 2023 г. The President of the Republic of Uzbekistan, According to nutritionists, the optimal daily require- Sh. Mirziyoev, in his Address to the members of the ment for linoleic acid is 6-10 g, and the minimum re- «Oliy Majlis» Senate and the Legislative Chamber on the quirement is 2-6 g, and the total amount in the diet results of 2019, stated that the requirements for quality should not be less than 4% [47]. in the production of products will increase, and set a number of tasks for improving the health of the popula- According to scientists, the optimal composition of tion and raising the standard of living. . oils designed to nourish a young and healthy body should contain 50% oleic acid, 20% cis-linoleic acid and In the Action Strategy for the further development 30% saturated fatty acids. In this case, the ratio of me- of the Republic of Uzbekistan, the tasks of \"Development dium and high molecular fatty acids should be 1:1 [83]. of agriculture, use of local raw material resources and The disadvantage of the composition is that ω3 fatty acids creation of technologies for their processing\" are defined. are not taken into account in the diet. According to data, the configuration of oleic acid is not important [83]. Industrially produced vegetable oils are a complex However, according to other data [84, 85, 86], excessive mixture of triglycerides, compounds and non-fatty sub- consumption of trans isomers of unsaturated fatty acids stances. has a negative effect on the body. The presence of plant tissue particles, moisture and The composition of fatty acids is greatly influenced other non-oily substances in the composition reduces the by the storage conditions of raw materials. Triglycerides quality and nutritional value of vegetable oils. of sunflower oil can undergo deep changes as a result of technological effects. Freshly harvested raw materials Although there are a small amount of auxiliary sub- do not contain 3p-2 saturated fatty acids. As a result of stances in the composition of vegetable oils, some of them hydrothermal treatment, triglycerides of palmitic and improve the physiological properties of the oil (phospho- stearic acid with 5p-2 structure were formed as a result lipids, tocopherols, carotenoids), while others worsen their of partial hydrolysis of triglycerides. At the same time, quality (free fatty acids, oxidation derivatives). the ratio of oleic and linoleic acids also changes. The re- fining process also affects the composition and posi- A number of requirements are imposed on refined tional structure of fatty acids [87, 88, 89]. oils, depending on their direction of use. Oils intended for consumption and dietary purposes are refined in a During the processing of freshly harvested raw full cycle. In this, their phospholipids, free fatty acids, materials, there are fewer changes compared to stored color and odor substances are removed. In this case, raw materials [90, 91]. During the processing of stored maximum preservation of triglycerides from the effects raw materials, the oxidation and hydrolytic processes of moisture, atmospheric oxygen, and chemical reagents that lead to the breakdown of the triglyceride composition is achieved. take place violently and destroy the physiological prop- erties of the oil [87, 92, 93, 94]. During the processing However, neither refined nor unrefined oils individ- of sunflower seeds stored for 4 months, the positional ually have optimal fatty acid content. Therefore, it is arrangement of triglycerides changes dramatically: necessary to mix them (coupage) to obtain vegetable oils 30% of palmitic acid and 50% of stearic acid change of the specified composition. to 5p-2 state. The concentration of linoleic acid in the 5p-2 state is lower than recommended for vegetable oils Research shows that it is possible to obtain enriched [87, 95, 96, 97]. oils with the desired biological value by creating two- and multi-component mixtures of natural oils. Thus, it is advisable to process raw materials that have not been stored for a long time in order to obtain Today, as a result of research carried out by domes- vegetable oils with high biological value that are stable tic and foreign researchers, lipids are not only effective to oxidation. Also, strict technological regimes should not energy reserves with high satiety, but also metabolically be used during the processing of raw materials. The fatty active substances depending on the balance of complex acid composition of vegetable oils obtained in mild re- physiological active substances in the fatty acid content gimes is presented in the table [98, 99, 100, 101]. of edible oil [82, 83]. Fattyacids Sunflower Values Typeofoil Oillessrapeseed Table 1. 0,1. -0,2 Olive 0...1 Myristin 5...8 Sunflowerwitholein 0-2,4 1...5 Flax Palmitin 1,9...7,0 - 9,8...20 0,5...2 - Stearin 0,2...0,5 do 2,9 0...1 TracesofArachin 0,4... 0,6 3...5 do 0,6 4...7 Begen 0...0,4 3...5 izlari 0,5...1,5 2...5 Lignocerin o...o,2 0...0,3 - - izlari Tracesofpalmitolein 10...13 0...1,0 1,0...2,2 Olein 0...0,5 0...0,4 54...81 izlari - Gadolein - 0...0,2 0,3 50...65 izlari Eruk 74...76 70...92 - 1...3 Linol 0...0,3 0...0,2 3,3...22 0...5 - Linolene 15...30 12...34 - 0,3... 0,8 6...13 2...20 - - - 14...20 35...65 66

№ 1 (106) январь, 2023 г. It should be noted that certain vegetable oils do not in the diet is only 7%, which is not enough for this need meet the optimal composition according to the content [83]. Thus, in nature there are no oils with the optimal of saturated and unsaturated fatty acids. structure necessary for the human body. In order to obtain the optimal composition of vegetable oils, it is advisable In experiments, mixtures containing sunflower or olive to process two or more oils by coupling in order to establish oil have been found to have a high biological value [102]. the correct ratio of ω3 and ω6 fatty acids. Although olive oil has a very good composition, it is not advisable to use only this oil in the diet. Despite the fact that there is a lot of information about this in the existing literature, there are a lot of con- According to nutritionists, the ratio of animal fats tent-contradictory opinions in them. Therefore, conducting and vegetable oils in the diet should be 2:1. But, in such research in this field is urgent. conditions, considering that vegetable oils contain only about 20% polyunsaturated fatty acids, the share of PNJK References: 1. Torakulov Y.X. Biochemistry. Tashkent: \"Uzbekiston\". -1996, -323 p. 2. Berezov T.T., Korovkin B.F. Biological chemistry. - M.: \"Medicine\", 1990. - P. 277. 3. \"Manual on research methods, technical control and accounting of production in oil and fat industry\". Under ob. ed. RzekhinaV.P. -L.: VNIIZH., t-I, book 1. - S. 32-98. 4. Kholdorov Bakhodir Baratovich, Ermatov Otabek Saidovich, son of Issakov Shokir Allaberdi, son of Sadullaev Jasur Mansur. Drying products with infrared rays. \"Universe: technical science\" 5(98). Moscow 2022. 5. Issakov Shokir Allaberdioglu Methods of optimization of the fruit drying process. \"Universe: technical science\" 6(99). Moscow 2022. 6. Issakov Shokir Allaberdi son, Kilichov Azizbek Abdugani son Method of accelerating drying process by initially working in impulse-pausemode \"Universum: technical science\" 11(104). Moscow 2022. 67

№ 1 (106) январь, 2023 г. VEGETABLE OIL OXIDATION PROCESS AND TECHNOLOGIES FOR ITS PREVENTION Furkat Chimpayizov Assistant, Jizzakh Polytechnic Institute, Republic of Uzbekistan, Jizzakh E-mail: [email protected] ПРОЦЕСС ОКИСЛЕНИЯ РАСТИТЕЛЬНЫХ МАСЕЛ И ТЕХНОЛОГИИ ЕГО ПРЕДОТВРАЩЕНИЯ Чимпайизов Фуркат Нахалович ассистент, Джизакский политехнический институт, Республика Узбекистан, г. Джизак ABSTRACT Under the influence of oxygen in the air, various oxidation derivatives appear on vegetable oils. Most of them dra- matically change the organoleptic and technological properties of oil. Oils that have begun to oxidize lose their stability during further storage and cause problems in processing. АННОТАЦИЯ Под действием кислорода воздуха на растительных маслах появляются различные производные окисления. Большинство из них резко меняют органолептические и технологические свойства масла. Масла, начавшие окис- ляться, теряют стабильность при дальнейшем хранении и вызывают проблемы при переработке. Keywords: oxidation, peretherification, radical, ketones, triglycerides, refining and deodorization. Ключевые слова: окисление, переэтерификация, радикал, кетоны, триглицериды, очистка и дезодорация. ________________________________________________________________________________________________ The President of the Republic of Uzbekistan, The main reason for our attention to this issue in the Sh. Mirziyoev, in his Address to the members of the analysis is that any impact on vegetable oils causes their «OliyMajlis» Senate and the Legislative Chamber on the physico-chemical changes. In particular, it is desirable that results of 2019, stated that the requirements for quality the improper conduct of the processes of pre-esterification in the production of products will increase, and set a and coupling not only prevents their deterioration during number of tasks for improving the health of the popula- further storage processes, but also increases their stability. tion and raising the standard of living. . Oxidized oils have a toxic effect on the body. Earlier, In the Action Strategy for the further development vitamins and other necessary substances were damaged of the Republic of Uzbekistan, the tasks of \"Development in this process, but today their direct toxic properties of agriculture, use of local raw material resources and are being identified. creation of technologies for their processing\" are defined. Modern views on the mechanism of oxidation are Industrially produced vegetable oils are a complex based on Bach-Engler's peroxide theory and Semenov's mixture of triglycerides, compounds and non-fatty sub- chain radical process theory. According to the theory of stances. peroxides, unstable peroxides are formed during the in- itial oxidation of oils. The subsequent splitting of the The presence of plant tissue particles, moisture and peroxide leads to deep changes and the emergence of other non-oily substances in the composition reduces stable derivatives. the quality and nutritional value of vegetable oils. Radical chain processes are understood as the repe- Today, as a result of research carried out by local tition of one or a number of reactions of radicals that and foreign researchers, lipids are not only effective en- preserve one or a number of active centers. The number ergy reserves with high satiety, but also metabolically of repeated radical reactions determines the chain length. active substances depending on the balance of complex physiological active substances in the fatty acid content The formation of two radicals from the transformation of edible oil. of one radical in the chain process is considered a branched radical-chain process. An example of such processes is Oxidation derivatives of different levels appear on the oxidation of organic substances under the influence vegetable oils under the influence of oxygen in the air. of oxygen. The appearance of branches is the result Most of them dramatically change the organoleptic and of radical decomposition of hydroperoxide. technological properties of oil. Oils that have begun to oxidize lose their stability during further storage and cause problems in processing. __________________________ Библиографическое описание: Chimpayizov F.N. VEGETABLE OIL OXIDATION PROCESS AND TECHNOLOGIES FOR ITS PREVENTION // Universum: технические науки : электрон. научн. журн. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14891

№ 1 (106) январь, 2023 г. In the formation of free radicals, oxygen molecules, • presence and amount of oxidation catalysts which are active biradicals at room temperature, are con- in the oil; sidered, and they take protons (primarily hydrogen at- oms in the alpha position of double bonds) from the fatty • presence and amount of oxidation inhibitors in acids themselves. the oil; Also, as factors causing the formation of radicals: • rays, radiation and other irradiating effects • metal ions with variable valency that exchange on the oil. electrons in the oxidation-reduction process; • various organometallic compounds; It is known that the rate of oxidation of a mixture of • temperature effect; fatty acids depends on the molar fraction of each com- • light and others can serve. ponent and its activity in the chain reaction. Also, the Free fatty acids help dissolve metals in oil and ac- selective effect of fatty acid residues in the mixture of celerate oxidation processes. triglycerides is important. For example, sunflower oil, In the initial process of oxidation, oxidation is slow. which is rich in palmitic and oleic fatty acids, is more As the number of radicals increases, the process accel- resistant to oxidation than oil rich in linoleic acid. erates according to the chain reaction. As a result, stable carboxylic groups (aldehydes, ketones) are formed that Natural antioxidants contained in oils are able to ef- have the ability to decompose oxygen-retaining radi- fectively maintain the oxidation process. Natural antiox- cals. idants include tocopherols, sesamol, gossypol, In the process of deepening of oxidation, under the phospholipids, polyphenols and a number of other sub- influence of oxidation derivatives, the mechanism of ox- stances. idation changes fundamentally. Under the influence of chains in the oxidation process, a number of reactions Among the antioxidants, tocopherols (vitamin E) begin to take place in parallel. These derivatives can not are of great importance. Tocopherols actively protect oils only accelerate the oxidation process, but also slow it from oxidation, but they themselves are oxidized, losing down. their vitamin properties. Tocopherols are quite resistant It is difficult to explain the process of oxidation of to high temperatures in the presence of oxygen, but they fats and oils with some kind of stoichiometric equation. are resistant to the effects of ultraviolet rays and some Because, depending on the composition of the oil, oxi- oxidants. dation and chain reactions take place differently. Regardless of how the process proceeds, 90% of the In the technological processes of extracting vegetable hydroperoxides formed have double bonds in the trans oils, the processes aimed at transferring natural inhibitors configuration. into the oil composition are important in preventing the Polyunsaturated linoleic and linolenic acids are very oxidation of oils. During the process of heat, pressure sensitive to oxygen. During their oxidation, linoleate and other effects during oil separation, it is necessary and lenolenates are formed, and the hydroperikis formed to try to preserve not only the oxidation of the oil, but also during their subsequent transformations are unstable and the natural preservation of tocopherols, carotenoids and easily transform into various oxygen-retaining derivatives. other necessary substances included in its composition. The presence of double bonds indicates a tendency to the formation of low molecular volatile substances The results of the latest research show that when oils on the one hand, and to the formation of polymers on the are marketed as natural as possible, despite the fact that other hand. the appearance of the product is slightly lower, the use- Taking into account the above-mentioned conditions, ful substances in it are preserved more. For example, af- the following conditions should be identified in the oxida- ter primary purification of sunflower oil, it is very useful tion of triglycerides: to release it without refining and deodorization. • acyl structure of fatty acids included in triglycer- ides; Refined oils are inferior to unrefined oils in their in- • oil storage temperature; dicators, especially in terms of oxidation stability. Cold- pressed oils have higher quality indicators than hot- pressed oils. However, unrefined oils differ in their in- stability to hydrolytic decomposition. In the process of storing oils, it was found that the stability to oxidation increases by 1.5-2.0 times when they are poured into brown or green packaging compared to transparent containers. References: 1. Address of the President of the Republic of Uzbekistan Sh.M. Mirziyoev aimed at setting the results of 2019 and priority tasks for 2020. https://www.gazeta.uz/uz/murojaatnoma 2. http://strategy.regulation.gov.uz/uz/document 3. Annex to the Decision No. 43 dated March 31, 2020 of the Economic Commission of the Economic Commission for the Eurasian Economic Union. http://www.eurasiancommission.org/ru/nae/news. 4. KholdorovBakhodirBaratovich, IrmatovOtabekSaidovich, son of IssakovShakirAllaberdi, son of SadullaevBrave Mansour. Drying products with infrared rays. \"Universum: technical science\" 5(98). Moscow 2022. 5. IssakovShokirAllaberdioglu Methods of optimization of the fruit drying process. \"Universe: technical science\" 6(99). Moscow 2022. 6. IssakovShokirAllaberdi son, KilichovAzizbekAbdugani son Method of accelerating drying process by initially work- ing in impulse-pausemode\"Universum: technical science\"11(104). Moscow 2022. 69

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Научный журнал UNIVERSUM: ТЕХНИЧЕСКИЕ НАУКИ № 1(106) Январь 2023 Часть 4 Свидетельство о регистрации СМИ: ЭЛ № ФС 77 – 54434 от 17.06.2013 Издательство «МЦНО» 123098, г. Москва, улица Маршала Василевского, дом 5, корпус 1, к. 74 E-mail: [email protected] www.7universum.com Отпечатано в полном соответствии с качеством предоставленного оригинал-макета в типографии «Allprint» 630004, г. Новосибирск, Вокзальная магистраль, 3 16+

UNIVERSUM: ТЕХНИЧЕСКИЕ НАУКИ Научный журнал Издается ежемесячно с декабря 2013 года Является печатной версией сетевого журнала Universum: технические науки Выпуск: 1(106) Январь 2023 Часть 5 Москва 2023

УДК 62/64+66/69 ББК 3 U55 Главный редактор: Ахметов Сайранбек Махсутович, д-р техн. наук; Заместитель главного редактора: Ахмеднабиев Расул Магомедович, канд. техн. наук; Члены редакционной коллегии: Горбачевский Евгений Викторович, канд. техн. наук; Демин Анатолий Владимирович, д-р техн. наук; Звездина Марина Юрьевна, д-р. физ.-мат. наук; Ким Алексей Юрьевич, д-р техн. наук; Козьминых Владислав Олегович, д-р хим. наук; Ларионов Максим Викторович, д-р биол. наук; Манасян Сергей Керопович, д-р техн. наук; Мажидов Кахрамон Халимович, д-р наук, проф; Мартышкин Алексей Иванович, канд.техн. наук; Мерганов Аваз Мирсултанович, канд.техн. наук; Пайзуллаханов Мухаммад-Султанхан Саидвалиханович, д-р техн. наук; Радкевич Мария Викторовна, д-р техн наук; Серегин Андрей Алексеевич, канд. техн. наук; Старченко Ирина Борисовна, д-р техн. наук; Усманов Хайрулла Сайдуллаевич, д-р техн. наук; Юденков Алексей Витальевич, д-р физ.-мат. наук; Tengiz Magradze, PhD in Power Engineering and Electrical Engineering. U55 Universum: технические науки: научный журнал. – № 1(106). Часть 5., М., Изд. «МЦНО», 2023. – 24 с. – Электрон. версия печ. публ. – http://7universum.com/ru/tech/archive/category/1106 ISSN : 2311-5122 DOI: 10.32743/UniTech.2023.106.1 Учредитель и издатель: ООО «МЦНО» ББК 3 © ООО «МЦНО», 2023 г.

Содержание 4 4 Papers in english 4 Chemical engineering 8 STUDY OF TEMPERATURE DEPENDENCE OF THE DEFORMATION PROPERTIES OF THERMOREACTIVE POLYURETHANE USING THERMOMECHANICAL METHOD 14 Asliddin Shodiyev Bakhodir Mukhiddinov 14 Sharifjon Kiyomov Durdona Ibodullayeva 19 RESISTANCE COEFFICIENTS OF THE APPARATUS WITH CONE MESH WET CLEANING 19 OF DUST GASES Ikromali Karimov Bobirmirzo Qo‘chqarov Electronics METASTABILITY AND CROSSING CLOCK DOMAINS IN AN FPGA Peter Safir Electrical engineering INVESTIGATION OF THE ELECTROPHYSICAL PROPERTIES OF COTTON FIBERS OF THE GRADE \"KAMOLOT-79\" ALLOYED WITH IODINE Abdugafur Mamadalimov Nilufar Khakimova Shokhzod Norbekov Mirjalol Norboyev

№ 1 (106) январь, 2023 г. PAPERS IN ENGLISH CHEMICAL ENGINEERING DOI - 10.32743/UniTech.2023.106.1.14917 STUDY OF TEMPERATURE DEPENDENCE OF THE DEFORMATION PROPERTIES OF THERMOREACTIVE POLYURETHANE USING THERMOMECHANICAL METHOD Asliddin Shodiyev Doctoral student of the Department of Chemical Technology Navoi State University of Mining and Technology, Republic of Uzbekistan, Navoi E-mail: [email protected] Bakhodir Mukhiddinov Professor of the Department of Chemical Technology, Doctor of Chemical Sciences, Navoi State University of Mining and Technology, Republic of Uzbekistan, Navoi Sharifjon Kiyomov Senior researcher 111116, LLC Tashkent Scientific Research Institute of Chemical Technology, Republic of Uzbekistan, Tashkent Durdona Ibodullayeva Master of the Department of Chemical Technology Navoi State University of Mining and Technology, Republic of Uzbekistan, Navoi ИССЛЕДОВАНИЕ ТЕМПЕРАТУРНОЙ ЗАВИСИМОСТИ ДЕФОРМАЦИОННЫХ СВОЙСТВ ТЕРМОРЕАКТИВНОГО ПОЛИУРЕТАНА ТЕРМОМЕХАНИЧЕСКИМ МЕТОДОМ Шодиев Аслиддин Фахриддин угли докторант кафедры “Химическая технология” Навоийского государственного горно-технологического университета, Республика Узбекистан, г. Навои Мухиддинов Баходир Фахриддинович д-р хим. наук, проф. кафедры “Химическая технология”, Навоийского государственного горно-технологического университета, Республика Узбекистан, г. Навои Киёмов Шарифжон Нозимович ст. научн.сотр., ООО «Ташкентского научно-исследовательского института химической технологии», Республика Узбекистан, г. Ташкент Дурдона Ибодуллаева Ихтиёр кизи магистр кафедры химической технологии Навоийский государственный горно-технологический университет, Республика Узбекистан, г. Навои __________________________ Библиографическое описание: STUDY OF TEMPERATURE DEPENDENCE OF THE DEFORMATION PROPERTIES OF THERMOREACTIVE POLYURETHANE USING THERMOMECHANICAL METHOD // Universum: технические науки: электрон. научн. журн. Shodiyev A.F. [и др.]. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14917

№ 1 (106) январь, 2023 г. АННОТАЦИЯ В этой статье образец полиуретана, был получен поликонденсацией 4,4-метилендифенилдиизоцианата и полиэфирполиола. Температурная зависимость деформационных свойств приготовленного образца полиуретана изучалась термомеханическим методом. ABSTRACT In this article, a polyurethane sample was obtained by polycondensation of 4,4-methylene diphenyl diisocyanate and a polyester polyol. The temperature dependence of the deformation properties of the prepared polyurethane sample was studied by the thermomechanical method. Ключевые слова: поликонденсация, деформация, температура стеклования, температура размягчения, аморфное состояние, температура перехода на высокоэластического состояния, статическое напряжение. Keywords: polycondensation, deformation, glass transition temperature, softening temperature, amorphous state, transition temperature to a highly elastic state, static stress. Introduction. Today, polymeric materials are widely polyolpolyisocyanates, polycarbonate polymers, used in all areas of the country's real economy. One of these epoxyurethane-based polymers, and other thermosetting main areas is the mining and metallurgical industry, polymers [3,4]. These 4,4-methylenediphenyl- which uses various pumps operating in aggressive diisocyanate-containing thermosetting polyurethanes environments. Polyurethane materials are used to increase also have a three-component network macromolecular the wear resistance of continuously operating pump structure, high temperature, chemical attack, deformation parts [1]. These coating parts wear out after a certain resistance and resistance to aggressive environments period of time due to wear and are replaced with new compared to thermoplastic polymer materials. In addition, polyurethane coatings. At the Navoi Mining and it is convenient to obtain various components from Metallurgical Combine (NMMC), 80-100 tons of liquid thermosetting polyurethanes [5, 6]. polyurethane material is accumulated as waste annually. The processing of these resulting wastes, as well as the Research object. Based on the collected data from study of the physical and mechanical properties of the the literature review, the stated goal of this study is to processed polyurethane material, are relevant [2]. In the study the thermomechanical properties of polyurethane production of parts with high properties, it is desirable based on 4,4-methylenediphenyl diisocyanate and to use thermosetting polymers. The main factor in the polyester polyol. production of a polymeric material of complex composition is a plasticizer, which forms the basis of the Table 1 lists the production parameters for the ther- polymer. At present, plasticizers are used to produce moset polyurethane material. Polyurethane with this polymers and polymer composites with high composition is used for lining internal walls of pumps physicochemical properties. These include, for example, pumping acid solutions, for a panel of sieves, as well as vibration damping bricks [7]. Table 1. Synthesis of polyurethane material Name of source material Weight part, g Temperature of the Crystallization Crystallization time, degassing process, o C temperature, o C hour 4,4-methylenediphenyl one hundred 90 diisocyanate Adipine acidifying ethylene gly- 50 75 110 24 col ether 1,4 -butenediol 4.8 25 Based on the values given in Table 1, a polyurethane Results and discussion. The transition interval sample was prepared and the thermomechanical properties of a polyurethane sample from one state to another under of this sample were studied [8 , 9]. the influence of various temperatures was determined by the thermomechanical method. The studies were carried Methods and materials out with the help of experiments, special devices, tools, as a result of which a graph of the temperature depend- Amorphous polymers, in addition to the state of ence of the deformation was built. glass transition and fluidity, also have a state of high elasticity, not found in other polymers. The state of high elasticity, fluidity, and the glassy state of the polymers were determined according to GOST 270-75 and GOST 32618.2-2014 on an RMI-60 testing machine [10]. 5

№ 1 (106) январь, 2023 г. Where: T S - softening temperature; T G is the glass transition temperature; T IHE - transition to a highly elastic state; T SIS is the beginning of strain inversion; T ERW - end of reverse warp Figure 1. Thermomechanical curve of a polyurethane sample From Fig. 1, the thermomechanical curve shows that elastic state in the temperature range of 135-160°C. Dis- at a temperature of 73 °C , the deformation of the urethane- tance between T IHE and T SIS thermomechanical curve is forming aliphatic groups occurs at a low temperature, called the upper elastic limit. The next section of the and the glass transition begins at a temperature of 116°C. thermomechanical curve is the interval between the points An increase in temperature leads to the transition of the T SIS and T ERW , in which the curve deviates from the upper polymer sample to a state of increased elasticity, which elastic limit, i.e., an inversion of the sample deformation occurred at a temperature of 135°C. Between T IHE and is observed. The inversion value of the strain is 25 µm. T SIS there is an increase in temperature from 135°C to 160°C, and it is found that with an increase in temperature The strain inversion of the sample occurred in the tem- perature range 135–160°C. Based on the above data, the there is a permanent deformation of the sample. This following table 2 was created. means that the diisocyanate polyurethane is in a highly Table 2. Thermomechanical parameters of the polyurethane sample Options 4,4-methylenediphenyl diisocyanate polymer Softening temperature, ° С 73 Temperature of transition to a highly elastic state, ° С 135 Temperature interval of the plateau of highly elastic , ° С Deformation inversion start temperature, ° C 135-160 End temperature of strain inversion, ° С 160 180 Based on the thermomechanical analysis data, the Conclusion graph curve showed that the polymer goes into a softened state, starting from 72 °C. The presence of a As a result of the research, it was found that at tem- high elastic plateau on the thermomechanical curve peratures below the melting temperature of a thermoset- indicates that the new polymer has a densely reticulated ting polyurethane sample, polyurethane is solid, its supramolecular structure, i.e., the polymer has a deformation is small, and at higher temperatures, the de- thermosetting character. formation increases sharply. It has been found that the viscosity of the polymer in the liquefied state decreases with increasing temperature. 6

№ 1 (106) январь, 2023 г. References: 1. A.F. Shodiev, doctoral candidate; B.F. Mukhiddinov, prof.; Kh.M. Vapoev, prof.; B.E. Yusupov, Deputy ch. engineer; F.J. Olikulov, assistant. (NMZ NMMC, Navoi, Uzbekistan) polyurethane waste recycling device Belarusian State Technological University January 31 February 12, 2022 p.167-169 2. Jalilov A.T., Kiyomov Sh. N. Urethane-epoxy thermosetting polymer systems as an antifriction material // Bulatov readings. - 2020. - V. 5. - S. 76-78. 3. BECKER-WEIMANN, Klaus, Walter HEHEN, Michiel FARLANDER. \"METHOD FOR PRODUCING REACTIVE POLYURETHANE COMPOSITIONS.\" (2010). 4. Nesterov S.V., I.N. Bakirova, and Ya. D. Samuilov. \"Thermal and thermo-oxidative degradation of polyurethanes: mechanisms of percolation, factors of influence and main methods for improving thermal stability. A review based on the materials of domestic and foreign publications.\" Bulletin of Kazan Technological University (2011): 10-23. 5. Bakirova I.N. Thermomechanical analysis of polyurethanes based on secondary raw materials // High-molecular compounds. Series B. - 1998. - T. 40. - No. 10. - S. 1666-1670. 6. Asliddin S., Bakhodir M., Sharifjon K. EFFECT OF CHANGE OF POLYETHROPOLIOL AMOUNT ON THE PHYSICAL-MECHANICAL PROPERTIES OF THERMOREACTIVE POLYURETHANE //Universum: technical sciences. – 2022. – no. 10-7 (103). - S. 22-26. 7. Kyomov Sh.N. et al. STUDY OF THE THERMOMECHANICAL PROPERTIES OF EPOXYURETHANE POLYMER // Editor-in-Chief: Akhmetov Sairanbek Makhsutovich, Doctor of Engineering. sciences; Deputy Editor- in-Chief: Akhmednabiev Rasul Magomedovich, Ph.D. tech. sciences; Members of the editorial board. - 2022. - S. 50. 8. Kyomov Sh.N., Jalilov A.T. ADHESION OF EPOXYURETHANE POLYMER ON METAL // Universum: technical sciences. – 2020. – no. 9-2(78). 9. AFShodiyev, BFMuxiddinov, Sh.N.Qiyomov No.-119-120 b. 10. Maik V.Z., Kulak M.I. Wear resistance of the polymer material of stamps for hot stamping // Proceedings of BSTU. Series 4: Print and media technologies. -2013. – no. 8 (164). - S. 19-22. 7

№ 1 (106) январь, 2023 г. DOI - 10.32743/UniTech.2023.106.1.14903 RESISTANCE COEFFICIENTS OF THE APPARATUS WITH CONE MESH WET CLEANING OF DUST GASES Ikromali Karimov Doctor of Technical Sciences (DSc), Associate Professor, Fergana Polytechnic Institute, Republic of Uzbekistan, Fergana Bobirmirzo Qo‘chqarov Assistant, Fergana Polytechnic Institute, Republic of Uzbekistan, Fergana E-mail: [email protected] КОЭФФИЦИЕНТЫ СОПРОТИВЛЕНИЯ АППАРАТА С КОНУСНОЙ СЕТКОЙ ВЛАЖНОЙ ОЧИСТКИ ОТ ПЫЛЕВЫХ ГАЗОВ Каримов Икромали Тожиматович д-р техн. наук, доц., Ферганский политехнический институт, Республика Узбекистан, г. Фергана Кочкаров Бобирмирзо Улугбекович помощник, Ферганский политехнический институт Республика Узбекистан, г. Фергана ABSTRACT The article presents the results of an experimental study conducted on a pilot plant with a mesh cone for wet dust cleaning. In the studies carried out, the local resistances of the devices and the resistance coefficients of the selected three different-sized grids were determined in the absence of splashing of the device with water, at variable gas flow rates. Based on the research results, the values of correction factors for calculating the resistance coefficient of the selected grids were determined. As a result, it was possible to calculate the total pressure loss depending on the total resistance coefficient in the contact devices of the apparatus. АННОТАЦИЯ В статье представлены результаты экспериментального исследования, проведенного на опытной установке с сетчатой конусом мокрого пылеочистки. В проведенных исследованиях определены местные сопротивления ап- паратов и коэффициенты сопротивления выбранных трех разно размерных сеток в условиях отсутствия забрыз- гивания устройства водой, при переменных значениях расхода газа. По результатам исследований определены значения поправочных коэффициентов для расчета коэффициента сопротивления выбранных сеток. В результате создано возможности рассчитать суммарные потери давления в зависимости от коэффициента полного сопро- тивления в контактных устройствах аппарата. Keywords: dusty gas, gas velocity, flow rate, wet method, liquid, cone mesh, resistance coefficient, correction factor. Ключевые слова: запыленный газ, скорость газа, расход, мокрый способ, жидкость, конусная сетка, коэффициент сопротивления, поправочный коэффициент. ________________________________________________________________________________________________ Introduction this case, the contact of dust particles occurs on the sur- face of a liquid film or liquid droplets. In the implemen- The cheapest and most convenient way to clean dust tation of this process, the flow of gas and liquid can and toxic gases in gas is the wet cleaning process. The move perpendicularly or oppositely [1,7]. essence of wet cleaning of dusty gases is to combine fine dispersed dust particles by wetting the dust particles. In If we analyze these devices from the point of view of constructive structure and efficiency, the indicator of __________________________ Библиографическое описание: Karimov I.T., Qo‘chqarov B.U. RESISTANCE COEFFICIENTS OF THE APPARATUS WITH CONE MESH WET CLEANING OF DUST GASES // Universum: технические науки : электрон. научн. журн. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14903

№ 1 (106) январь, 2023 г. cleaning various industrial dusts is 97-99%. But the Research object complexity of the structural structure of these devices, the energy spent on them, and the high hydrodynamic As an object of research, the experimental device of and aerodynamic resistance in the device can be pointed the cone meeting device created at the department of out as a general drawback [1,3,4,7]. In order to eliminate “Technological machines and equipment” of Fergana the aforementioned shortcomings and to increase the Polytechnic Institute (Fig. 2) and the formula for calcu- contact surface between the dusty gases and the liquid lating the total resistance coefficient lost in the device supplied to the device, a new design of the dusty gas [3,4], which was created as a result of theoretical re- cleaning device was recommended [3,4]. Below is a di- search, were used. agram of the device (Fig. 1). 1- lower conical sludge bath, 2- upper conical cleaning chamber, 3- conical screen, 3a-screen support, 4-water sprinkling nozzle, 5-water distribution pipe, 6- powder gas inlet pipe, 7- cleaned gas discharge pipe, 8- water tank, 9- water drum, 10-water pipe, 11-water rotameter, 12- sludge discharge pipe, 13- sludge drum, 14- sludge, 15-dust air driving fan, 16- dust air bag, 17 - rotameter, 18- dust gas transfer pipe Figure 1. Schematic of the device with a cone а) б) Figure 2. Overview of the cone-shaped apparatus 9

№ 1 (106) январь, 2023 г. Technical indicators of the device with a cone 1. Volume of dust hopper V=0.000836 m3 7. Water sprinklers 2. Vacuum pipe 7.1 Number of sprinklers, n=12 2.1. Diameter dc = 100 mm 2.2. Length Ls = 250 mm 7.2. Hole diameter, dsh=1 mm. 3. Dust air intake pipe 8. Liquid rotameter PC-3 3.1. Diameter Dk = 100 mm 3.2. Length Lk = 150 mm 9. Water pump: GVSm 370 4. Purified air exhaust pipe 9.1. Power: N=0.37 kW/h 4.1. Diameter Dch = 200 mm 4.2. Length Lch = 200 mm 9.2. The number of rotations n1=2900 0 r/min. 5. Device dust cleaning chamber 10. Fan: Model: DF-7 5.1. Height Ht= 900 mm 10.1. Power: N= 550w 5.2. Large base radius Rt =350 mm 5.3. Small base radius rt =100 mm 10.2. The number of rotations n2=2800 r/min. 5.4. Volume V=0.157785 m3 11. Overall dimensions of the device 6. one with mesh 11.1. Height Н = 2600 mm 11.2. Width В=1160 mm 6.1. Height Hk= 700 mm 6.2. Large base radius Rk =350 mm 12. Water tank 6.3 Small base radius rk =45 mm 6.4. Grid dimensions. а=1,1mm; 12.1. Length L=0,6 mm а=1,3mm; а=1,6mm. 12.2. Width В=0,3 mm 6.5. Mesh cone volume V=0,1027748 м3 12.3. Height H=0,4 мм 12.4. Volume V=0,072 m3 6.6. The side surface of the netted cone, Sside = 0.9178 m2 13. Sludge bath 6.7. Cone maker with mesh, l=740mm 13.1. Length L=0,6 mm 13.2. Width В=0,3 mm 13.3. Height H=0,4 mm 13.4. Volume V=0,072 m3 The obtained results To calculate the total pressure lost in the apparatus, on the A-A section is determined as follows depending it is necessary to determine the local resistance of the on the total surface of the grid through which dusty apparatus and the coefficients of resistance of metal air passes and the diameter of the wire of the grid and the dimensions of the square holes of the grid [3,4] m2; grids with different hole sizes, which are installed on the с = k  (R + r)  lс   (3) metal drum, which is the main working body of the ap- a  paratus. Therefore, GOST 3826-82, 12X18N10T stain- where ∆k is the correction coefficient, determined less steel mats made of square holes of 3 different sizes through experiments, R- is the radius of the base of the were selected in experimental studies (Fig. 2, b). Grid conical grid, m; r-radius of the cut part of the conical dimensions 1. Square hole size a=1.1 mm, wire thick- ness δ=0,16mm; 2. Square hole size a=1.3 mm, wire mesh, m; lc - the average value of the length of the circle thickness δ=0,18 mm; 3. Square hole size a=1.6 mm, wire of the base of the mesh and the length of the circle of the thickness δ=0,2 mm; cut part, m; δ -grid wire diameter, m; a- mesh square The theoretical total resistance coefficient of the de- hole dimensions, m. ξch - when dusty air is discharged from the device vice is equal to the following [3]. through a pipe, the coefficient of internal friction is de- gen = к + b +  f (1) fined as follows [5,6,7]. where ξк is the coefficient of internal friction when transferring dusty air to the device through a pipe, defined f = 2  l (4) as follows [5,6,7]. d к =  1 2l1  (2) where λ2 is the coefficient of friction in the pipe for  D + d1  releasing the purified air from the device; l- is the length   of the pipe through which the purified air moves, m; d-pipe diameter, m; where λ1 is the coefficient of friction with the pipe wall introducing dust gas into the device, l- is the length If we add the values of formulas 2, 3, 4 -to the of the pipe through which dust gas is moving, m; D-section above-mentioned formula 1, it will look like this. cone base diameter, m; d-is the diameter of the truncated  gen =  1 2l1  + k  (R + r) lс    + 2  l  D + d1  a  d part of the cone.   ξс - is the resistance coefficient of the drum mesh (5) and is determined as follows. From Fig. 1 and 2, the total resistance coefficient of the truncated conical grid 10

№ 1 (106) январь, 2023 г. Through this equation, the total resistance coeffi- A view of the resulting regression equation: 1. y = 20,388x - 0,9395 R² = 0,9881 cients of the apparatus are determined. 2. y = 20,388x - 0,3395 R² = 0,9881 At the initial stage of the experiments, a damper Figure 3. Graph of variation of resistance coefficient ξgen and ξс depending on Σδ/Σa (moving barrier) was installed on the gas suction part of (in the case of no liquid spraying) the fan that transmits the dust gas to the apparatus. The Based on experimental studies, research was con- damper was changed in the range of 30÷900 (with 150 ducted to determine the values of the correction coeffi- cient Δк depending on the resistance coefficient of the steps) and the gas velocities coming out of the fan and recommended grids. Relative resistance coefficients of selected grids were determined. Below is the calculation the corresponding gas consumption were determined. method. According to it, when Shiber is opened to 300, 1- calculation of a truncated conical grid. Wire Qg=170m3/h, when opened to 450, Qg=340m3/h, when thickness- = 0,16mm ,Hole size k =1,(1) . opened to 600, Qg=510m3/h, when opened to 750, Qg=680m3/h, when opened to 900, Qg=850m3/h. In the First of all, we take a square shape with sides of 10 sm by 10 sm as a sample. next course of experiments, a fan was installed in the apparatus body, and the above-determined gas con- sumption was given as Q=170÷850 m3/h (with a step of 170 m3/h), and the gas consumption was determined by the gas velocities coming out of the apparatus. In this case, Shiber was Qg=107m3/h when opened to 300, Qg=220m3/h when opened to 450, Qg=318m3/h when opened to 600, Qg =438m3/h when opened to 750, Qg =512m3/h when opened to 900. The local resistance coefficient of the device was determined from the differ- ence in gas consumption. Anemometer VA06-TROTEC brand electronic device was used to determine these differences at all stages of experiments. The average local resistance coefficient of the device was x=0.6. At the next stage of the experiments, cones with a square hole size a=1,1; 1,3; 1,6 mm were installed in the appa- ratus body in a row (Fig. 2b) Q=170÷850 m3/hour (with a step of 170 m3/hour) was supplied to each gas drum installed in the apparatus. Experimental studies were carried out separately for each cone grid. In the experiments, the gas density was chosen at ρg=1,29 kg/m3 (for air). According to the re- sults, the resistance coefficient ξс =2,6 when the mesh square hole size is a=1,1mm, the thickness of the mesh wire is δ=0,16mm; ξс = 2.5 when the hole size is a=1,3mm, the mesh wire thickness is δ=0,18mm; hole size a=1,6mm, mesh wire thickness δ =0,2mm ξс=2,2. These determined resistance coefficients are the overall resistance coefficient of the apparatus, plus the local resistance coefficients of the apparatus. If we sub- tract the local resistances from these values, the grid re- sistance coefficients are derived. The local resistance coefficient is determined as follows. м = (к +  f ) (6) с = gen − (к +  f ) (7) a=1,1mm, when the mesh wire thickness is δ=0,16 mm; Figure 4. Graphic image ξс=ξgen- ξм=2,6-0,6=2 S10 = Ssim + Ssolid 8) a=1,3mm, when the mesh wire thickness is sim δ=0,18mm; ξс= ξgen- ξм=2,5-0,6=1,9 Sside = 0, 95м2 ; S10 = 10000мм2 = Ssim + Ssolid ; a=1,6mm, when the mesh wire thickness is δ=0,2 mm sim ξс= ξgen- ξм=2,2-0,6=1,6 a1 = 0,1690 =14, 4мм ; The obtained experimental results were processed a2 = 0,1690 =14,4мм. on the basis of a computer program and a graph of de- pendence was built (Fig. 4). 11

№ 1 (106) январь, 2023 г. S10 = (a1 + a2 ) 100мм = Here н - is the relative resistance coefficient of sim the grid, Ssim.gen - we determine the total surface cov- = (14, 4 +14, 4) 100мм = 2880мм2 ered by the wire in the mesh wrapped around the side S10 = Sside = 950000 мм 2 = 95 . Sc 10000 мм 2 surface of the truncated cone by the ratio of Sbox.gen - There are 95 check boxes in total where: the total free cells in the mesh wrapped around the side surface of the truncated cone by the ratio of the surface Sside - the side surface of the truncated cone sur- (non-wired part): rounded by mesh, Ssim.gen 273600 Sbox.gen 676400 S10 -10 cm. a surface covered with wires at a distance н = = = 0, 40449 sim of 10 cm, a surface covered with wires at a distance of 10 cm S10 -10 cm and a surface covered with empty We determine the correction coefficient K . sim cells, K =  n a1 - the total thickness of the wires on one side of (11) the isolated mesh sample, a2 - the total thickness of the wires on the other side of the isolated mesh sample, To do this, we divide the experimental resistance coefficient ξ by the relative resistance coefficient ξn. Ssim - the surface covered by the wire in the isolated K =  = 2 = 5 sample, Sbox - the sum of the areas of the empty cells n 0, 4 in the isolated sample. To find the total area covered by wire in the net, we multiply 95 pieces by S10 -(that is, the size of the surface The correction factors for subsequent grid sizes sim were also determined in the same way. The size of the of 10 cm by 10 cm): square hole of the mesh is a=1,3mm. The thickness of Ssim.gen = S 10  S10 (9) the mesh wire is δ =0,18 mm. when ΔК =5,1. The size sim of the square hole of the mesh is a=1,6mm. When the Ssim.gen = S 10  S10 = 2880 95 = 273600 мм 2 . thickness of the mesh wire is δ=0.2 mm, the correction sim factor is equal to ΔК =5. For selected grid sizes, it is rec- To find the surface occupied by the total empty ommended to take the correction factor in the range ΔК=(5-5.1). cells, we subtract the total surface covered by Ssim.gen To simplify calculations, the coefficient of local re- wire from the Sside surfaces: sistance in the inlet and outlet pipe of dusty air to the That is: device was ξм=0.6. In that case, formula 5, which calcu- lates the total resistance of the device, will look like this. Sbox.gen = Sside − Ssim.gen = .  gen = 0, 6 + k  (R + r)  lс   (12) a  = 950000мм2 − 273600мм2 = 676000мм2 So: Sbox.gen = 676000мм2 ; Ssim.gen = 273600мм2 ; Summary Sside = 950000мм2 . As a result of experimental studies, the local re- Here: Sbox.gen - Cut is the surface occupied by the sistances of the arrarat and the resistance coefficients of the selected three different sizes of grids were deter- total number of empty cells in the mesh wrapped around mined in the condition that the device was not sprinkled the side surface of the cone (wireless part). with water, at step variable values of gas consumption. According to the results of the study, the values of the Ssim.gen - The total surface covered with a wire mesh correction coefficients for calculating the resistance co- efficient of the selected grids were determined. As a re- wrapped around the side surface of a truncated cone. sult, it is possible to calculate the total lost pressure depending on the total resistance coefficient in the con- Sside - the side surface of a truncated cone surrounded tact devices of the apparatus. by mesh. We find the coefficient of relative resistance of the set:  Ssim.gen 10) =н Sbox.gen 12

№ 1 (106) январь, 2023 г. References: 1. Вальдберг А.Ю., Николайкина Н.Е. Процессы и аппараты защиты окружающей среды. – М. : Дрофа, 2008. – 239 с. 2. I.T. Karimov, B.U. Kochkarov. Wet method dust gas cleaning device // The american journal of enjineering and tehnology, 2021.№03.-PP. 20-26. 3. Ikromali T.Karimov, Bobirmirzo U. Kochkarov “WET METHOD DUST GAS CLEANING DEVICE” Proceeding VIII International Conference “Industrial Technologies and Engineering” ICITE - 2021, Volume II. M. Auezov South Kazakhstan University, Shymkent, Kazakhstan November 10-11,2021. 4. Каримов И.Т., Қучқаров Б.У. “Чангли газларни ҳўл усулда тозаловчи янги аппарат” Фарғона политехника институти илмий – техника журнали Scientific-technical journal (STJ FerPI, ФарПИ ИТЖ, НТЖ ФерПИ, 2021, T. 24, спец. № 1. 5. Латипов К.Ш. Гидравлика, гидромашиналар ва гидроюритмалар. – Тошкент: Ўқитувчи, 1992. –405 б. 6. Мадаминова Г. И., Тожиев Р.Ж., Каримов И.Т. Барабанное устройство для мокрой очистки запыленного газа и воздуха // Universum: технические науки. – 2021. – №. 5-4 (86). – С. 45-49. 7. Сугак Е.В. Очистка газовых выбросов в аппаратах с интенсивными гидродинамическими режимами Е.В. Сугак., Н.А. Войнов, Н.А. Николаев – Казань: Риц и «Школа», 1999 - 224 с. 13

№ 1 (106) январь, 2023 г. ELECTRONICS DOI - 10.32743/UniTech.2023.106.1.14893 METASTABILITY AND CROSSING CLOCK DOMAINS IN AN FPGA Peter Safir Bachelor of Science, The Azrieli College of Engineering in Jerusalem (JCE) Israel, Jerusalem E-mail: [email protected] МЕТАСТАБИЛЬНОСТЬ И ПЕРЕСЕЧЕНИЕ ТАКТОВОГО ДОМЕНА ПРИ ИСПОЛЬЗОВАНИИ ПЛИС Сафир Петр Павлович Бакалавр наук, Академический инженерный колледж Азриэли, Израиль, Иерусалим ABSTRACT What is metastability? What is meant by the crossing clock domain? This paper looks at the basic notion of metastability and the reasons for its 'appearance'. This includes analyzing data, discovering metastable states, and uncovering the nature of their nature. This paper also looks at basic techniques for crossing clock domains. What is setup time and hold time and why it is important they are correctly followed. The FIFO concept is the best option for crossing different clock domains and avoiding metastable states. We will also examine the Mean Time Between Failures (MTBF) formula. АННОТАЦИЯ Что такое метастабильность? Как правильно пересечь тактовый домен? В этой статье рассматривается поня- тие метастабильности и причины ее появления, а также как избежать этого состояния. Рассматриваются основные техники пересечения тактового домена, понятия \"setup time\" и \"hold time\". FIFO как лучший вариант для пересечения тактового домена. Мы также рассмотрим формулу среднего времени наработки на отказ (MTBF). Keywords: FPGA, crossing clock domain, metastability, flip flop, FIFO, MTBF. setup time, hold time. Ключевые слова: FPGA, ПЛИС, метастабильность, регистр, MTBF, межрегистровая передача. ________________________________________________________________________________________________ Introduction see where in the project there is time and frequency slack, and if it is unnecessary to increase the frequency If you are writing FPGA-based projects with fre- of the clock domain. Different clock domains and their quencies less than 20MHz, you have probably not expe- crossing within one FPGA is common problem, but rienced any of the following problems described below. many inexperienced digital circuit engineers do not In any professional FPGA-based project after synthesis know how to resolve this properly or in which cases to of the project, you will need to create a set of ‘time- use a specific algorithm. limit’[1] files. Without these files, when the FPGA is running, you will not know for sure where in the project D - flip flop and metastable state the data processing is interrupted. After synthesizing[2] our project, we get a file with physical connections of When the clock signal changes from \"0\" to \"1\" on our elements inside the FPGA and a time analyzer em- the input, the D flip flop stores the current data value on bedded in our developer program is used to calculate the input D, and sends it to the output Q. With any other how much time it takes to transfer signals inside of the value of the edge of the clock signal, the value on Q re- FPGA. On the basis of this analysis, the developer can mains unchanged. An asynchronous reset signal can also be present on the triggers to reset the output D. __________________________ Библиографическое описание: Safir P. METASTABILITY AND CROSSING CLOCK DOMAINS IN AN FPGA // Universum: технические науки: электрон. научн. журн. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14893

№ 1 (106) январь, 2023 г. Figure 1. D - flip flop and truth table For the correct operation of the d flip flop, there are • Ts - setup time. The d-flip flop input signal D, two time intervals related to the data reception on the D must remain stable for a minimum setup time before channel. This time is needed to stabilize the output the rising edge of the clock signal. signal. • Th - hold time. The minimum hold time after the rising edge of the clock signal. Figure 2. Setup time and hold time \"The time window\" of these two parameters in the comes to the input D, close to the rising edge of the clock vicinity of the rising clock signal is the time during signal and retains the old value or forms a new value, which the signal D must be stable. If the d flip flop is but we do not know what it is. In in the worst case we stabilized within this \"time window\", it is guaranteed to will get an oscillating output signal between high and capture the incoming data to input D and transmit it to low level, which means there is a delay in switching the output Q without failure. An important point to note is output to a stable state. This state is called the metastable the time window Ts and Th are clearly defined by the state at the output Q. After a certain time d flip flop will FPGA manufacturers and is not decided by the engineer go into one of the stable states of 0 or 1, but when, and and is created by time analysis utilities. The main pur- which one, is impossible to predict. The metastability of pose of timing analysis is to calculate the timing slack for one d flip flop, can unsynchronized other parts of the a pair of registers between which data is exchanged. project, because usually one d flip flop sends an output signal to several d flip flops simultaneously thus the sys- • Setup slack - time margin from the moment tem cannot extricate out of such a state independently of stabilization and to the beginning of setup time. without causing a general failure in the process. Given that such a situation may occur regularly, it is possible • Hold slack - time margin at the end of the hold to estimate the probability of such an event. The time and before the loss of stabilization. following formula (1.1) explains time between failures: • For asynchronous reset there is also \"a time win- ������������ (1.1) dow\" and it is known as recovery time and removal time. The signal Q on the d flip flop output comes with a cer- ������ ������ tain time delay. If the Ts or Th \"time window\" is vio- ������������������������ = ������������������С������0 lated, the Q signal on the d flip flop output can go into an undefined state. Sometimes when \"the time window \" is violated on the output Q we receive a signal which 15

№ 1 (106) январь, 2023 г. • Rt - time interval of protection against metasta- The most common causes of metastability. bility, ideally tends to 0 for one D flip flop, is equal to • Violation of \"the time windows\" Ts and Th for the period of the clock signal minus the delay for setting signal stabilization. and propagation for the second D flip flop, plus the pe- • Asynchronous reset in d flip flop must be syn- riod for each subsequent D flip flop. chronized to the clock signal of the d flip flop itself where the reset occurs. • τ is a technological parameter measured in pico- • Transmit asynchronous signals at a different fre- seconds. quency relative to the clock frequency of the receiving d flip flops. • ������0 - \"The time window\" of entry into metastability, • Wrong synchronous signal from other external measured in picoseconds. devices. It is necessary to set the time characteristics of the incoming signals. • ������с - Clock signal d flip flop. • ������������ - frequency of data change from 0 to ������с. Figure 3. Clock domain crossing When there is only one operating frequency for the A solution to the problem of metastability and syn- whole project, it makes the job a lot easier, but in com- chronization Single-bit signal plex projects there are a lot of clock domains. Data from sensors uses its frequencies, SDRAM, reads and writes To reduce metastability in the simplest case for a work on its frequencies, while data coming from external single-bit signal, we add two d flip flops at the frequency devices, works on other frequencies. All of these different of the receiving first trigger. If the first trigger enters a frequencies feed into the FPGA, and all of it must be metastable state, then with high probability, it will pass synchronized to avoid metastability problems. to the moment of fixation in the second trigger, and after the third trigger will the signal become stable, 0 or 1. Figure 4. Single-bit signal stabilization circuit Clock domain crossing second domain goes in. The first register of the second clock domain works as a synchronization register Clock domain crossing, the single-digit signal to minimize the number of metastable failures, and to give extra time to bring the signal to a stable state, To transfer a single-bit signal from one clock do- so that it may safely be transferred to the new clock do- main to another clock domain, we use the circuit below, main. pic 1.5. The clock of the first domain goes in the first register, and in the second two registers the clock of the 16

№ 1 (106) январь, 2023 г. Figure 5. Single-bit signal. Clock domain crossing circuit Clock domain crossing, data stream. memory by using the ip catalog built into any FPGA de- (multi-bit signal) sign editor. We write data into the FIFO at the first clock domain and read it out at another frequency, in another To transfer a large amount of data from one clock clock domain. The only limitation is that we cannot domain to another, requires using a dual port memory[] write and read data on the same address at the same time. which allows you to read and write data from different Also, do not read data from an empty FIFO, or write data ports at different frequencies. You can build such a onto a full FIFO. It can cause a system failure. Figure 6. 2 port FIFO Conclusion and synchronization. This adds a certain time delays to the project, but this must be taken into account. All external In general, the fewer the clock signals in the project, signals including the reset signal are asynchronous the fewer the problems. The higher the frequency of the to our FPGA project and must be synchronized. One FPGA, the less chance of a metastable failure because asynchronous signal is synchronized to the project clock \"the time window\" Ts and Th are less than slow FPGAs. once. All internal clock signals, such as PLL[4] or DSP[5] When transferring from one clock domain to another, module signals, are synchronous to the timing analyzer, it is necessary to use synchronization registers, or even and do not require re-synchronization. better, FIFO. This will avoid problems with metastability References: 1. Steve Kilts. Advanced FPGA Design: Architecture, Implementation, and Optimization. 1st Edition. Wiley-IEEE Press 2007. P.89 - 110. 2. Roger Woods, John McAllister, Gaye Lightbody, Ying Yi. FPGA-based Implementation of Signal Processing Systems. 2nd Edition. Wiley 2017. P. 120 – 145. 3. Doug Amos, Austin Lesea, Ren Richter. FPGA-Based Prototyping Methodology Manual: Best Practices in Design-For- Prototyping. Synopsys Press 2011. P.87 – 110. 4. Jim Ledin. Architecting High-Performance Embedded Systems: Design and build high-performance real-time digital systems based on FPGAs and custom circuits. Packt Publishing 2021. P.56 – 101. 5. Uwe Meyer-Baese. Embedded Microprocessor System Design using FPGAs 1st ed. Kindle Edition. Springer 2012. P. 135-150. 17

№ 1 (106) январь, 2023 г. 6. Clive Maxfield. The Design Warrior's Guide to FPGAs: Devices, Tools and Flows (Edn Series for Design Engineers). Newnes 2004. P. 89 – 95. 7. Philip Simpson. FPGA Design: Best Practices for Team-based Design. Springer 2010. P. 120 – 156. 8. Juan José Rodriguez Andina, Eduardo de la Torre Arnanz, Maria Dolores Valdés Peña. FPGAs: Fundamentals, Ad- vanced Features, and Applications in Industrial Electronics. CRC Press 2017. P. 35 – 87. 9. Wayne Wolf. FPGA-Based System Design (Prentice Hall Modern Semiconductor Design Series). Prentice Hall 2004. P. 120 – 143. 10. Seetharaman Ramachandran. Digital VLSI Systems Design: A Design Manual for Implementation of Projects on FPGAs and ASICs Using Verilog. Springer 2007. P. 102 – 136. 11. Ian Grout. Digital Systems Design with FPGAs and CPLDs. Newnes 2008. P. 23 – 87. 18

№ 1 (106) январь, 2023 г. ELECTRICAL ENGINEERING DOI - 10.32743/UniTech.2023.106.1.14934 INVESTIGATION OF THE ELECTROPHYSICAL PROPERTIES OF COTTON FIBERS OF THE GRADE \"KAMOLOT-79\" ALLOYED WITH IODINE Abdugafur Mamadalimov Doctor of Physics and Mathematics Sciences, Academic, National University of Uzbekistan Named After Mirzo Ulugbek, Uzbekistan, Tashkent E-mail: [email protected] Nilufar Khakimova Candidate of Physics and Mathematics Sciences, PhD, National University of Uzbekistan Named After Mirzo Ulugbek, Uzbekistan, Tashkent E-mail: [email protected] Shokhzod Norbekov PhD student, National University of Uzbekistan Named After Mirzo Ulugbek, Uzbekistan, Tashkent E-mail: [email protected] Mirjalol Norboyev Undergraduate, National University of Uzbekistan Named After Mirzo Ulugbek, Uzbekistan, Tashkent E-mail: [email protected] ИССЛЕДОВАНИЕ ЭЛЕКТРОФИЗИЧЕСКИХ СВОЙСТВ ХЛОПКОВЫХ ВОЛОКОН СОРТА \"КОМОЛОТ-79\" ЛЕГИРОВАННЫХ ЙОДОМ Абдугафур Мамалимов Тешабаевич док физ-мат наук, академик Национального университета Узбекистана имени Мирзо Улугбека, Республика Узбекистан, город Ташкент E-mail: [email protected] Хакимова Нилуфар Каримкуловна канд. физ.- мат. наук, PhD Национального университета Узбекистана имени Мирзо Улугбека, Республика Узбекистан, г. Ташкент Норбеков Шохзод Мамарасулович aспирант, Национального университета Узбекистана имени Мирзо Улугбека, Республика Узбекистан, г. Ташкент Норбоев Миржалол Бахромович магистрант Национального университета Узбекистана имени Мирзо Улугбека, Республика Узбекистан, г. Ташкент __________________________ Библиографическое описание: INVESTIGATION OF THE ELECTROPHYSICAL PROPERTIES OF COTTON FIBERS OF THE GRADE \"KAMOLOT-79\" ALLOYED WITH IODINE // Universum: технические науки : электрон. научн. журн. Mamadalimov A. [и др.]. 2023. 1(106). URL: https://7universum.com/ru/tech/archive/item/14934