Optimization Of Technological Processes Research Articles

Development of a demulsifier and technological process study for the preparation of highly viscous heavy oils for refinement

One of the challenges in the petroleum industry is the production of highly viscous heavy oils, often accompanied by undesirable emulsion formation with very high aggregate stability. To prepare the crude oils for refinement, the oils must be destroyed. The destruction of aqueous emulsions containing highly viscous heavy oils is an intricate task owing to the comparatively small disparity in water and oil densities, as well as the high viscosity of the dispersive medium and its high content of mechanical impurities. The problem of the destruction of petroleum emulsions arises desperately during the desalination and dehydration of crude oils with a high content of emulsifiers (resins, asphalts, paraffin, etc.) The creation of a highly efficient demulsifier and the development of an optimal technological process for the preparation of highly emulsifying oils that are distinguished by the composition and quantity of emulsifiers of West Siberian oils, which are widely refined in Russia, are the ways to resolve this challenging and timely issue. This study focuses on the viscous heavy oil of the Verbliouje deposit in the Astrakhan region. It also explains the creation of an effective demulsifier for the destruction of petroleum emulsions characterized by a very high emulsifying power and the fundamental principles of the development of deep dehydration technology and desalination of such high-viscosity heavy oils.

Активизация пластовой микрофлоры для повышения нефтеотдачи

Constant optimization of technological processes of oil production is one of the integral parts of rational subsurface use. The study and implementation of new developments and technologies in the oil production process is primarily due to the economic effect. Methods of increasing oil recovery are of particular interest in the practical implementation of innovative technologies in the oil and gas industry. To date, a huge number of technologies have been developed and tested in field conditions aimed at preserving and increasing the volume of produced products, the classification of which is very diverse. The primary criteria for choosing a method or combination of methods of influencing a productive reservoir in order to increase oil recovery are the geological conditions of the productive horizon, as well as the composition and physico-chemical properties of reservoir fluids. Currently, of all the many methods of increasing oil recovery, the microbiological method is the least studied, as a result of which it is extremely rarely used in enterprises. The relevance of research on the effects of microorganisms on the reservoir rock is beyond doubt. The possibility of widespread application of oil recovery enhancement technology based on bacterial life processes is interesting both from the point of view of environmental safety and economic efficiency. One of the microbiological methods of increasing oil recovery is the activation of the existing reservoir microflora by feeding a nutrient medium into the reservoir. In the course of their vital activity, some types of bacteria are capable of destroying clay rocks, which entails changes in the filtration and capacitance properties of the reservoir rock and, as a result, the volume of products produced increases significantly. The advantage of this method is the absence of the need for forced “contamination” of the reservoir formation, since the necessary bacteria are already in it.

METALLOGRAPHIC ANALYSIS OF NON-METALLIC INCLUSIONS IN SEMI-KILLED STEEL (GRADE 25G2S) DEOXIDIZED WITH A COMPLEX ALLOY Fe-Si-Mn-Al

This study presents a metallographic analysis of non-metallic inclusions in steel samples obtained from six different heats of the oxygen converter shop at JSC «Qarmet» and under laboratory conditions at the Karaganda Industrial University. The investigation focused on semi-killed steel samples deoxidized using traditional technology under industrial conditions and with a complex alloy containing Fe-Si-Mn-Al under laboratory conditions, aiming to identify the types and assess the level of contamination by non-metallic inclusions. The results revealed the presence of various types of non-metallic inclusions, such as corundum, chromite spinel, chromium oxides, as well as titanium nitrides and carbonitrides. The degree of contamination by non-metallic inclusions ranged from 2 to 3 points. The analysis showed that the use of a complex Fe-Si-Mn-Al alloy instead of traditional deoxidizers can affect the quantitative and qualitative composition of non-metallic inclusions. It was established that the complex alloy promotes the formation of more stable inclusion phases, which can positively impact the mechanical properties of the steel. It was also found that different production technologies and the use of deoxidizers can significantly influence the quantity and types of non-metallic inclusions, requiring further study and optimization of technological processes. Therefore, the results of this study can be valuable for metallurgical enterprises in selecting optimal steel deoxidation methods and improving steel quality, as well as for further scientific research in the fields of metallurgy and materials science.

Methods of Multi-Criteria Optimization of Technological Processes in a Fuzzy Environment Based on the Simplex Method and the Theory of Fuzzy Sets

Many modern technological objects in practice are characterized by the uncertainty of the initial information necessary for their management. Recently, one of the pressing scientific and practical problems is the development of new optimization methods for controlling the operating modes of such objects in a fuzzy environment. In this regard, the objective of this study is to develop methods of multi-criteria optimization in a fuzzy environment by modifying the simplex method and various optimality principles based on fuzzy mathematics methods. The methodology of the proposed study is based on a hybrid approach, which consists of the integrated use and modification of simplex methods and optimization methods with various optimality principles for working in a fuzzy environment. The main results are as follows: a simplex method of multi-criteria optimization of immeasurable criteria (here, we are talking about the impossibility of physical measurements of criteria, the values of which are estimated by decision maker); a theorem on the convergence of the solution sequence obtained using the proposed method to the minimum value of the criteria; a heuristic method based on a modification for fuzziness and a combination of the maximin and Pareto optimality principles, which allows effectively solving multi-criteria optimization problems in a fuzzy environment. The heuristic method proposed will be used to solve a real production problem—optimization of the technological process of benzene production.

Viscosity of deep eutectic solvents: Predictive modeling with experimental validation

Viscosity, the measure of a fluid's resistance to deformation, is a critical parameter in many industries. Being able to accurately predict viscosity is essential for the successful design and optimization of technological processes. In this research, regression models were created to predict the viscosity of deep eutectic solvents (DESs). Machine learning models were trained using a data set of 3440 data points for two component DESs. Different algorithms, such as Multiple Linear Regression, Random Forest, CatBoost, and Transformer CNF, were employed alongside a variety of structural representations like fingerprints, σ-profiles, and molecular descriptors. The effectiveness of the models was assessed for interpolation tasks within the training data and extrapolation outside of it. The results indicate that a rigorous splitting of the dataset into subsets is necessary to accurately evaluate the performance of the models. Two new choline chloride-based DESs were prepared and their viscosities were measured to evaluate the predictive capabilities of the models. The CatBoost algorithm with CDK molecular descriptors was chosen as the recommended model. The average absolute relative deviations (AARD) of this model exhibited fluctuations during 5-fold cross-validation, ranging from 10.8 % when interpolating within the dataset to 88 % when extrapolating to new mixture components. The open access model was presented in this study (http://chem-predictor.isc-ras.ru/ionic/des/).

Methodology of sensory analysis in improving the technology of canned fruit beverages

The Ukrainian fruit juice market is competitive and consumers prefer products that have high organoleptic characteristics and retain the maximum amount of nutrients. The study analyses the current state of the fruit beverage market, in particular apple juice, in Ukraine, with a focus on organoleptic properties that influence consumer choice. The relevance of the study lies in the need to improve the technologies for the production of canned fruit juices, in particular apple juice, to ensure compliance with modern consumer requirements for product quality and safety. The fruit juice market in Ukraine is competitive and consumers prefer products with high organoleptic characteristics and retaining the maximum amount of nutrients. Given the change in consumer preferences and increased interest in healthy eating, there is a need for a comprehensive analysis of consumer expectations and sensory properties of products. The aim of the study was to identify the main factors influencing consumers' choice of apple juice, assess the quality of products of the five leading brands in the Ukrainian market (Nash Sik, Jaffa, Galicia, Rich and Biola), and develop recommendations for improving organoleptic characteristics to increase the competitiveness of products. Based on the developed questionnaire, a survey was conducted to determine consumer preferences and the formation of the juice market. The results of the survey revealed a high level of consumer interest in new types of varietal fruit juices, which underlines the importance of research in this area. The main results of the study showed that the juice of the Rich brand meets consumer expectations the best, particularly in terms of taste and aroma. Consumers noted the importance of naturalness of products and the absence of artificial additives, which emphasizes the need to improve production technologies to preserve the natural composition and taste. Recommendations have been developed to improve the quality of apple juice, including optimization of technological processes, increasing the content of nutrients in the final product and ensuring compliance with consumer expectations. The results obtained can be used to increase the competitiveness of products in the market and expand the range of fruit juices in line with current trends in healthy eating.

Optimization of technological processes in the manufacturability of varistors based on recycled ZnO product, with emphasis on environmental sustainability

The main objective described in this paper is the optimization of technological parameters in the production of varistors based on recycled zinc oxide (ZnO). The content of this paper builds on our previous research aimed at proving that hydrometallurgically recovered ZnO material, from electric arc furnace dust, is suitable for applications in these semiconductors, an issue which has received very little attention at present. The focus of this research also corresponds to and supports the visions and strategies of environmental sustainability and the circular economy. Samples of ZnO varistors manufactured for this purpose were analyzed by scanning electron microscopy and then the electrical parameters were measured and calculated. Based on the results of the microstructural analysis and electrical properties, prerequisites for the optimal adjustment of technological parameters such as sintering temperature and sintering time were derived, which will be the starting point for further research.

Investigation of the influence of milk protein genotype on the process of fermentation of milk curds by mesophilic lactic acid streptococci

The relevance of this study lies in the fact that the majority of commercial milk processed into fermented dairy products is a mixture of β-casein genotypes. The increasing use of A2 milk in the dairy industry necessitates the development of scientifically grounded technologies for the production of fermented products, as casein genotype modifications can affect the course of technological processes and require adjustments to production parameters. The study aimed to determine the impact of genetic modification of the β-casein protein in cow’s milk on the fermentation process of milk mixtures during the production of fermented dairy products. Research methods included chemical, physical, organoleptic, and microbiological methods (determination of the quality indicators of raw milk and fermented milk curds), and technological methods (determination of acid formation activity and viscosity). The initial characteristics of raw milk were investigated according to genotype, revealing no direct correlation. Changes in the physicochemical, microbiological, and organoleptic properties of fermented milk curds during biotechnological processing and storage were examined. Optimal technological process regimes were selected, and technological methods were chosen to minimise the influence of secondary factors on the experiment. A mixed culture preparation of mesophilic lactic acid lactococci, including L. Lactis ssp., was chosen as a starter culture. It was established that all 13 milk samples were suitable for biotechnological processing using mixed cultures of mesophilic lactic acid bacteria. As a result, it was concluded that the production of fermented dairy products from raw milk with the presented β-casein genetic modifications, A1A1, A1A2, and A2A2 – using L. lactis ssp. cultures – is possible using the classical technology and does not require adjustment of the technological conditions. The obtained results can be used in the dairy industry when developing technologies for fermented dairy products from A2 raw milk

Analytical study on improving the efficiency and environmental friendliness of solid organic fuels

The purpose of this study was to analyse methods of increasing the efficiency and environmental friendliness of the use of solid organic fuels (SOF) in electricity generation. This study employed a comprehensive approach to the analysis and optimisation of technological processes, operational systems, and environmental aspects of the use of SOF. The study found that the use of modern technologies, such as gasification and pyrolysis, considerably increases the efficiency of converting SOF into electricity. Optimisation of boiler and turbine designs and automation of fuel supply systems helps to reduce energy losses and improve overall system efficiency. It was found that the use of new materials for boilers increases their resistance to corrosion and erosion, which extends the service life of the equipment. The study also showed that the introduction of gas cleaning and secondary combustion systems significantly reduces emissions of harmful substances, which improves environmental performance. An analysis of ash utilisation opportunities showed that its use as a fertiliser or construction material is a promising area. The study proved that an integrated approach to the use of SOF can substantially increase their efficiency and environmental friendliness. The findings of the study suggest that the use of innovative methods of combustion process control allows achieving more stable and efficient power generation. It was proved that the introduction of automated monitoring and control systems reduces operating costs and increases the reliability of equipment. The study also found that the use of advanced analytical tools to predict equipment wear and tear allows for prompt preventive maintenance, which further increases the efficiency and duration of uninterrupted operation of energy systems

In Ukrainian

Blood loss is one of the main causes of death, especially in war and natural disasters. At the beginning of the full-scale Russian-Ukrainian war we established the laboratory and later the industrial production of a powdered topical hemostatic composition based on nanosilica which is intended for providing first pre-medical aid. The composition contains nanosized silica A-300 and sodium alginate as two active ingredients in a mass ratio of 4:1. The aim of the work was to develop the optimal technological process for the production of a hemostatic composition and carry out physico-chemical and medical-biological studies of semi-finished products and the final product. Bulk density measurements, optical microscopy, IR spectroscopy method and microbiological research were used to study the initial materials, intermediate products as well as the final product. The effectiveness of the hemostatic effect of the composition was checked on the model of parenchymal bleeding from the liver of a rat, using the time to stop bleeding (min) as a criterion. As a result of the research, a two-stage method of manufacturing the composition is proposed: at the first stage, certain parts of the initial materials are treated in a ball mill, obtaining the semi-finished product "A-300/sodium alginate"; at the second stage, this semi-finished product is mixed with nanosilica and sodium alginate, obtaining the final product. It is shown that the bulk density serves as a useful technological parameter to control of which helps to produce a structurally homogeneous final product. In the IR spectra of the semi-finished product and the finished product, only the absorption bands of silica and sodium alginate are observed, that is, foreign substances are not formed during technological process. The microbiological purity of the composition meets the pharmacopoeial requirements for drugs of this category. An experimental study of the topical hemostatic effect of the composition revealed its significant advantage compared to the inorganic hemostatic substance kaolin, which acts according to a similar adsorption mechanism.

Design of a decision support system to form optimal technological processes for parts machining based on artificial intelligence methods

The object of this study is the process of designing a decision support system for automating the formation of technological processes (TPs) for machining parts of high-precision equipment for the aviation industry. The task of improving the efficiency of the optimization of the process of mechanical processing of parts through the use of a decision support system (DSS) and artificial intelligence methods, which, unlike known analytical approaches, allow describing processes and phenomena that do not have strict formalization, has been solved. DSS consists of three subsystems. The first is an information subsystem for the automated formation of the structure in the technological process of machining parts of high-precision equipment. The second is an information subsystem for optimizing parameters of TP operations by cutting, taking into account the accumulation of tool wear. The third is a subsystem of control and adjustment of operating parameters. In the process of conducting research, an approach was devised for designing optimal technological processes to machine parts of high-precision equipment. The task of designing the structure of technological processes was solved using production rules. The task of determining the optimal parameters of turning and milling operations was solved in a multi-criteria statement. The following objective functions were used: cost of the operation, specific energy consumption for the operation, and productivity of the operation. At the same time, the wear of the tool accumulated over time was taken into account. The solution was obtained by searching for the Pareto-optimal solution using genetic algorithms and artificial neural networks. As a result of the work of DSS, an optimal technological process for machining parts of high-precision equipment for the aviation industry was formed, which made it possible to reduce the production time of one part by 5 % and reduce the total cost of production of the part by 14 %

Crop rotation as a biological factor of weed control in spring barley crop in the Sonkovsky district of the Tver region

Spring barley is widely used for fodder and food purposes. Modern farming systems involve the use of short crop rotations, which leads to a deterioration in the phytosanitary condition of the fields, so improving the structure of the fields is a priority. The potential of the crop will not be fully exploited if local resources are used irrationally. Weed components, in turn, inhibit crop growth and reduce the amount of product obtained. Successful weed control is based on a systematic approach involving agrotechnical, biological and chemical measures. The pursuit of yield without the optimization of technological processes leads to low profitability of agricultural production, so a properly selected predecessor is the key to profit for agricultural producers. The aim of the study is to regulate barley weeds in the Tver region using biological methods. Crop rotation is the cheapest method without material costs. Predecessors have a different effect on the species and quantitative composition of weeds. The maximum clogging in the sum of weed vegetation, including biological groups, was found for the oat predecessor (62 pcs/m2 of juvenile weeds and 53 pcs/m2 of perennial weeds). The best predecessor for spring barley in the experiment is corn for silage, after which the number of Erysimum cheiranthoides decreased to 3 pcs/m2, which caused an increase in the yield of the studied crop from 4.5 to 7.4 t/ha.

Numerical Investigation on Flowability of Pulverized Biomass Using the Swelling Bed Model

Numerical investigations on the flowability of pulverized biomass are crucial for agriculture, aiding in optimizing biomass use, crop residue management, soil health improvement, and environmental impact mitigation. Rising interest in biomass and conversion processes necessitates deeper property understanding and technological process optimization. Moisture content is a key parameter influencing biomass quality. In this paper, computer simulations of shear tests depending on the moisture content using the discrete element method were carried out and compared with experimental results. An experimental study and modeling for Jenike’s direct shearing apparatus was carried out. A swelling bed model was proposed to account for the effect of moisture. The swelling bed model assumed an increase in biomass grain vorticity proportional to the moisture content. The model was solved using the discrete element method (DEM). The model considers the effect of moisture on the values of Young’s and Kirchoff’s moduli for biomass grains. The model assumed that moisture is not present in surface form, the total amount of moisture is absorbed into the interior of the material grains, and the volume of a single grain increases linearly with an increase in the volume of the absorbed moisture. The tested materials were pulverized sunflower husks, apple pomace, distiller’s dried grains with solubles (DDGS), meat and bone meal (MBM), and sawdust. Samples with moisture contents of 0%, 10%, 20%, and 30% were tested. The best agreement of the model with the experimental data was observed for the most absorbent materials in which moisture was not present in surface form, such as apple pomace, DDGS, and sawdust. Research data are important for the proper design of biomass storage, transportation equipment, and utilization as feedstock for bioenergy production or soil enrichment.

ELEMENTS OF TECHNOLOGY OF ELECTRON BEAM WELDING OF ALUMINUM ALLOYS FOR INSTALLATION AND REPAIR AND RESTORATION WORK ON THE SURFACE OF THE MOON

The exploration of the Moon cannot be carried out without the creationof long-term lunar bases (LB), as well as other objects that ensure the livelihoods and work of expeditions. These can be assembly and assembly operations during the creation of space complexes or repair and maintenance work related to ensuring the duration of operation of existing systems. Experiments on automatic welding in space, which were carried out on the “Vulkan” equipment, as well as welding with the manual electron beam tool «URI» in outer space, showed that electron beam welding (EBW) is the optimal technological process for performing welding work in space conditions. In this process, the effective efficiency is 85—90 %, which is the maximum compared to other welding methods. EBW in the conditions of terrestrial gravity allows us to ensure the mechanical and chemical properties of welded joints, as well as their density almost at the level of the base metal of the structure, which is impossible with other welding methods. Thus, the strength coefficient of the weld metal of welded joints from aluminum alloys obtained by EBW is 0.85...0.93, and with arc and plasma-arc methods, it is 0.7…0.8. At the same time, obtaining such properties of welded joints in space conditions is difficult. Of course, reduced gravity, low temperatures, and ultra-high vacuum, which are the natural environment on the lunar surface, contribute to the formation of internal leaks in the form of pores in welds (PW). This is primarily manifested in the welding of aluminum alloys, which are used as the main material in spacecraft structures.To obtain high-quality welded joints and exclude such defects as pores, cracks, and non-fusion of edges in the weld roots to be welded, a system of equipment for periodic deflection of the electron beam with a programmable heating intensity along a given trajectory was developed and manufactured. As a result of technological work carried out using a complex of equipment with a discrete deviation of the electron b eam, welded joints (WJ) were obtained from alloys AMg6, A1570, and 1201 with a thickness of 2 to 8 mm. The obtained PW was subject to visual inspection and X-ray control to determine external and internal defects in the WJ. Also, mechanical tests for the strength of resistance by tearing were carried out, the chemical composition was determined, and metallographic studies of PW obtained by the proposed method were performed. The results of the tests and studies showed the high quality of PP from aluminum alloys obtained by EBW using a discrete deflection of an electron beam with a programmable heating intensity along a given trajectory. The purpose of this work was to analyze the methods of degassing the molten metal of the weld pool, as well as the development and testing of the elements of the technological process of the EBW of aluminum alloys using the created equipment, which, when performing installation and repair and restoration work on the surface of the moon, will allow us to obtain high-quality WJ that meets the requirements for space designs.

Experimental Verification of Calculation Formulas for Hydraulic Characteristics of Ash Suspension Removal

Abstract The article presents a comprehensive analysis of the hydraulic characteristics of ash suspensions, in particular the removal of ash from the Dnieper Hydroelectric Station. The importance of this research is justified by the relevance of understanding hydrodynamic processes in suspensions, which is crucial for the efficiency of mineral resource processing. The study focuses on the investigation of the physico-chemical properties of suspensions, which is fundamental for the development and optimization of technological processes. The main goal of the article is to determine the discrepancies between theoretical calculations and experimental data in the context of the hydraulic characteristics of ash suspensions. Focusing on this issue, the research aims to make an important contribution to the accuracy of prediction and calculation of the behavior of suspensions, which has important practical applications. The research methodology includes a series of experiments to measure various hydraulic parameters of the suspension, including suspension density, solid phase weight content, and porosity. The experiments are based on a detailed analysis of ash samples collected from the Dnieper Hydroelectric Station. It is established that theoretical formulas for determining hydraulic characteristics are well confirmed experimentally. The difference is due to the accuracy of measuring the density of the solid phase and errors in measuring weight and volume; it is sufficiently small and does not have a fundamental character.

DEVELOPMENT OF RECOMMENDATIONS FOR OPTIMIZATION OF TECHNOLOGICAL PROCESSES OF PROCESSING AND USE OF HEAT AND MASS EXCHANGE EQUIPMENT FOR DRYING LEGUMES

The article is devoted to the development of recommendations for the optimization of technological processes of processing and the use of heat and mass exchange equipment for drying legumes. Legumes are an important source of protein and other nutrients in the food and feed industry, and their drying plays a key role in preserving and increasing shelf life. The article includes analysis of technological processes, selection of optimal heat and mass exchange equipment, control of temperature and humidity, reduction of losses of useful substances and implementation of a quality monitoring and control system. Optimizing these processes will help increase production efficiency and improve the quality of dried leguminous herbs, contributing to the development of the industry and meeting the demand for valuable products. In this context, our article is devoted to the development of recommendations for the optimization of technological processes of processing and the use of heat and mass exchange equipment for drying legumes. By combining scientific analysis, practical experience and innovative approaches, we set ourselves the task of developing integrated recommendations that will contribute to increasing the efficiency of the drying process, reducing the loss of useful substances and improving the quality of dried legumes. An important aspect of our article is not only the theoretical base and scientific research, but also a practical approach to solving this problem. We hope that the developed recommendations will find practical application in the agro-industrial sector, contributing to the conservation of resources, increasing the quality and competitiveness of products and contributing to the sustainable development of this important industry.

THERMODYNAMICS OF STEPWISE DISSOCIATION OF GLYCYL-D-PHENYLALANINE IN AQUEOUS SOLUTION

Recently, more and more drugs that are derivatives of oligopeptides have been introduced to the pharmaceutical market. The structural elements of these compounds are amino acids and dipeptides. When stabilizing functional groups are introduced into the peptide structure, as well as through the use of special delivery systems, oligopeptide derivatives can be used as innovative medicines. The calorimetric method was used to determine the heat of interaction of glycyl-D-phenylalanine with solutions of nitric acid and potassium hydroxide at 298.15K and the values of the ionic strength of the solution 0.5, 0.75 and 1.0 in the presence of KNO3. Measurements were carried out on a calorimeter with an isothermal shell and automatic recording of the temperature-time curve. The unit was equipped with a reaction vessel with a volume of 60 cm3. Calibration was performed by current at T = (293.15–308.15) ± 0.01 K and P = 100.5± 0.7 kPa. A thermistor KMT-14 was used as a temperature sensor. The temperature of the calorimetric cell was controlled in a thermostat equipped with a PID controller with an accuracy of 0.002 K. The temperature sensor of the thermostat was a platinum resistance thermometer. The calorimeter was calibrated by current. The volume of the calorimetric liquid is 42.83 ml. The enthalpy of stepwise dissociation of glycyl-D-phenylalanine at zero ionic strength was found by an equation with one individual parameter. Standard thermodynamic characteristics (ΔrH°, ΔrG°, ΔrS°) of acid-base interaction reactions in aqueous solutions of glycyl-D-phenylalanine are calculated. The effect of the background electrolyte concentration on the dissociation heats of glycyl-D-phenylalanine is considered. Knowledge of the thermochemical characteristics of dipeptides is necessary for understanding and subsequent modeling of the process of protein biosynthesis occurring in biological systems. Data on the thermodynamic characteristics of dipeptide solutions are needed in various fields where these compounds are used: pharmacology, medicine, food and cosmetic industries, for the development, justification and optimization of technological processes involving these compounds and their complexes with metals.

Development of automatic control system of drum boiler on the basis of fuzzy controller with pid-controller adaptation

The aim of the study is to reduce energy losses in a drum steam boiler by introducing an automatic control system realized on the basis of fuzzy adaptation of proportional-integral-derivative (PID) controller coefficients using fuzzy term-multiplications. Control algorithms of the main technological parameters of the boiler unit (air quantity, fuel quantity, steam pressure, feed water flow rate), reducing energy costs due to the maintenance of the ratio of fuel and air pressure in accordance with the mode map of the boiler unit (optimal technological process of combustion and steam formation in a steam boiler) are developed. The structural scheme of the object control is offered, in which, besides regulation of values of technological parameters, full compensation of mutual influence of all regulation circuits is made.

On the Development and Adaptation of a Predictive Model of Full-Factor Optimization of The Basic Probiotic Fermented Dairy Product Technological Process

The purpose of building a predictive model for optimization of technological processes probiotic fermented dairy product.

Technological process optimization and measurement of image quality of the electrically bifocal metalens.

This Letter describes the design procedure and process optimization of the electrically bifocal metalens. In our design, horizontal and vertical polarization is manipulated by applying a suitable voltage to a twisted nematic liquid crystal (TN-LC) cell. Each nanostructure is designed to be a rectangular prism, making different polarizations of light experience various phase delays, thus causing bi-focus. We selected lithographical methods to fabricate our metalens because of the minimum physical size, which can be as small as 50 nm, and the maximum aspect ratio, which is as high as 15. Furthermore, to increase the tolerance and make the sidewall vertical and smooth, we coated different characteristics of photoresist sensitivity to the upper and lower layers. After the development, the mushroom-type photoresist makes Ni easier to strip while in the lift-off process, thus increasing the quality of the whole metalens. Our experiment shows that the focal lengths and focusing efficiencies corresponding to the two polarizations are similar to the simulation results. The proposed electrically modulated bifocal metalens can be utilized in different applications and combined with other optical components.