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The processes of obtaining freons by processing anode gases during the production of nuclear-grade zirconium have been studied. Anode processes in the production of zirconium by electrolysis of K2ZrF6 - KCl - KF, K2ZrF6 - KCl - KF - KI and ZrF4 - KCl - KF are considered. The disadvantages of using the traditional electrolyte K2ZrF6 - KCl - KF are revealed. It is shown that the introduction of potassium iodide in the amount of 0.03-0.5% iodine into the electrolyte reduces the discharge of chlorine at the anode and its concentration in the anode gas to 1%. It has been established that due to a decrease in the KCl discharge in the presence of iodine ions, this makes it possible, when operating the electrolyzer with a current load of 10 kA on the electrolyte K2ZrF6 - KCl - KF - KI, to increase its productivity by 6%, to reduce the consumption of KCl from 218.0 kg to 40.0 kg per day, while reducing the formation of ballast (KF) by 1.8 times stabilizes the electrolyte level and the electrolysis process. This contributes to an increase in current efficiency, while increasing to 65%, and reducing the consumption of electricity and salts: when KI is introduced, the consumption of a mixture of K2ZrF6 and KCl salts decreases by 1.7 times, and the specific consumption of NaOH alkali for gas purification from chlorine drops from 0, 7 t to 0.01 tons per 1 ton of Zr. The specific power consumption is reduced by 16 kWh/kg. It has been established that the replacement of K2ZrF6 with ZrF4 and a decrease in electrolyte fluoride by 3–5% contributes to an increase in electrical conductivity and current efficiency up to 78%, which makes it possible to reduce the specific power consumption to 40 kWh per 1 kg of powder. The processing of products of anodic reactions is shown to allow obtaining fluoro-chloro-derivative hydrocarbons, in particular, freons F-11 - F-14. It has been established that the freon yield when using electrolyte K2ZrF6 - KCl - KF is 1.00, K2ZrF6 - KCl - KF - KI - 0.78 and ZrF4 - KCl - KF - 1.50 kg/kg of zirconium powder. [ABSTRACT FROM AUTHOR]

Microwave irradiation (MWI) in the synthesis of materials has been an actively developing branch of science for the last three decades. Structures based on calcium phosphates (CaP) are one of the most well-known and widely used synthetic biomaterials in orthopedics and dentistry. The main topic of this review is the use of MWI in the formation of biomaterials based on calcium phosphate phases and their complexes with biopolymers (chitosan, alginate, silk fibroin). The physical bases of MW interaction with different materials are considered, including the influence of this irradiation on the structure, physicochemical and mechanical properties of biomaterials (crystallite size, porosity, strength, capability to absorb and release drugs). The main heating mechanisms during MWI are described, namely: the dipolar losses, and losses of conductivity. Important advantages of MWI treatment are reducing processing time, reducing electricity use, reducing waste and improving quality of the synthesized biomaterials. A list and comparison is made of articles describing the production of HA crystals with different morphology (nanowires, spherical, needleand rod-shaped) with all the initial conditions and their effect on the synthesized material. The latest developments in the field of biomaterials conducted based on the laboratory “Bionanocomposite” of Sumy State University are considered. The original synthesis method of CaP-biopolymer materials is described, as well as the advantages of the synthesized scaffolds over foreign developments. It is expected that this review of the interdisciplinary topic will contribute to the further study of other new applications of microwave technologies in the synthesis of the latest modern biomaterials created by scientists, biomedical engineers in other laboratories and institutions in Ukraine and around the world. [ABSTRACT FROM AUTHOR]

New and perspective method of extraction with usage of electromagnetic field is reviewed. The article provides advantages of using extraction in electromagnetic field over traditional methods of extractions. The main problem of traditional extraction technologies are retrieval incompleteness of targeted components and duration of the process. The article considers possibilities and perspectives of using oak wood extracts in different industries. The main scientific and technical contradiction of extraction was formulated. New hypothesis of extraction in electromagnetic field was proposed. The article provides methodology of experimental research, detailed description of devices which were used in the study and parameters of conducted experiments where water was used as extractant. Thermograms, changing of light transmission index and electricity consumption of all five series of experimental research are given in the article. Concentration comparison of dry matter in final extracts are given. The series of experimental research of extraction of oak wood using ethyl alcohol as extractant were also conducted, the parameters of research, thermograms, changing of light transmission index, electricity consumption and comparison of concentrations of dry matter are represented in the article. Article offers new innovative technology of highly extractive wines based on usage of microwave technologies and oak wood as an alternative to wines aging in oak barrels. Short organoleptic descriptions of obtained extracts and wines are given. The hypothesis about obtaining polyextracts by using polar extractants in electromagnetic field was proved. The mechanodiffusion effect was confirmed. It was confirmed that extraction of targeted components in MW extractors is 2,5…5 times higher than in traditional methods of extraction, energy consumption is 1,5…2 times lower than in traditional ones. It was defined that film and circulating extractors have advantages in obtaining high quality polyextracts from oak wood with higher rate of extraction of targeted components and have perspectives of industry application [ABSTRACT FROM AUTHOR]

Purpose. The aim of the work is to improve the work of hair styling devices, which is aimed at increasing the efficiency of hair styling under the action of sufficiently high temperatures with the least damage to it. To achieve this goal, the following tasks were solved: the relationship between the physical properties of hair and temperature regimes of curling was analyzed; experimentally investigated the distribution of curling temperature during heating and cooling; the distribution of the temperature of the curling iron when heated with dry hair and with moist hair was experimentally studied. Methodology. The methods of mathematical modeling, methods of mathematical physics, methods of experimental researches with processing of results of experiment by means of a modern software product and computer equipment are used in the work. Findings. Analytical and experimental studies have shown the need for a uniform temperature field on the surface of the work surface to achieve the desired result. The necessity of temperature regulation in devices for work with hair is proven. Originality. The possibility of using the installation for experimental evaluation of temperature control in devices for working with hair is substantiated, which will significantly increase the time of continuous operation of the device and reduce electricity consumption. Practical value. A stand for research and analysis of different temperature regimes of electrical appliances has been developed. The thermostat circuit for temperature control in devices for work with hair is applied. It has been proven that you need to choose the temperature in relation to the condition and type of hair, so as not to cause great harm. Due to its small size, economic and technical indicators, this stand is easy to use when studying the temperature conditions in devices for working with hair in the work space, which contributes to more modern and demonstrative training. It is proposed to use the two-position law of temperature regulation for the surfaces of the working bodies. [ABSTRACT FROM AUTHOR]

Purpose. The aim of the work is the development of mathematical models and the study on their basis of the characteristics of electrical consumption in higher educational institutions (using the example of hostels of the Kiev National University of Technology and Design). Method. Multiple regression analysis and intelligence analysis in combination with computer software implementations of the corresponding statistical procedures were used. Results. On the basis of real statistical data, regression models of power consumption in buildings of higher educational institute (hostels) were obtained, which was a logical continuation of the studies covered in [1]. The obtained results made it possible, by means of modeling, to carry out a predictive assessment of power consumption levels and to check their authenticity, comparing them with real data of the university’s energy management service for previous years. Scientific novelty. Methods of power management using regression models in buildings of higher educational institutions received further development. Based on an extended set of factors influencing the process of electricity consumption, the dependencies obtained for the first time were studied, which can be used to develop scenarios of energy management of higher educational institute in specific periods of the educational process, taking into account the season and energy efficiency class of buildings. Practical significance. The simulation results can be used to develop guidelines for the implementation of a set of energy-saving measures in higher education institutions, taking into account the existing engineering infrastructure and improving the efficiency of power management. [ABSTRACT FROM AUTHOR]

Purpose. The deduction of settlement ratios and the development of a method for calculating the energy saving effect from the use of a shunt active filter in a three-phase four-wire power supply system and its testing on the example of monitoring the parameters of electricity consumption of the hostel number 7 KNUTD. Methodology. Based on the symbolic method of calculating three-phase circles, the formulas for calculating the electrical resistances of phase and neutral wires of a three-phase four-wire system based on measurements of stresses of reference loads carried out by AEEAS KNUTD are grounded. The energy saving effect of using a shunt active filter in a three-phase four-wire system of power supply is established taking into account its own losses, which are determined on the basis of monitoring of parameters of electric energy consumption and calculated values of resistance of wires. Findings.The work substantiates the methodology for calculating the energy saving effect from the use of a parallel active filter in the three-phase four-wire power supply system, taking into account its own losses, and on the example of monitoring the parameters of electricity consumption of the hostel number 7 KNUTD demonstrated the possibility of reducing by 10-20% energy losses in the transmission line with the use of modern shunt active filters. Originality.The new analytical dependences of the operating voltages of the reference loads on the electrical resistances of phase and neutral wires of the three-phase four-wire power supply system used to calculate the values of the indicated resistances based on the results of phase voltage measurements are established. Practical value. A new method of calculating the energy saving effect from the use of a shunt active filter in a three-phase four-wire power supply system is formulated, which makes it possible to assess the expediency of using shunt active power filters and formulate requirements for their parameters in order to obtain the desired effect for a particular object of power consumption. [ABSTRACT FROM AUTHOR]

Purpose. Explore the possibilities of management programs usage to control electricity demand in Ukraine. To develop an optimization mathematical model of the power consumption regime based on key indicators of the consumption schedule estimation and equipment flexibility factors. Methodology. Proved that as a result of demand side management programs for electricity are benefit of only for consumers and energy companies, but also for a whole society. Classification of demand management programs for electricity according to spheres of action presented. The article deals with the method for electricity consumption daily schedule optimization while implementing electricity demand management programs. Findings. The effects of demand management programs implementation and reducing consumption schedule unevenness problems based on optimization task with the schedule coefficient and the cost of electric energy reduction have been analyzed. The conducted variants research of demand side management programs influence on possibilities of electric energy consumption schedule modification confirmed the possibilities of increasing power systems functioning efficiency. Originality. Optimized energy consumption graphs are obtained based on key indicators for a group of the same type consumers, considering consumer interests, which enables to assess the effect demand side management programs implementation. Consumers peculiarities are considered by coefficient of their demand flexibility kг. Practical value. The mechanism for the DSM innovation programs for optimizing power consumption regimes introduction possibility evaluation has been obtained. Established that domestic electric energy consumers have a significant potential for peak consumption reduction by usage of demand side management programs aimed at costs reduction for consumers and increasing the electrical consumption schedule filling ratio for energy companies. [ABSTRACT FROM AUTHOR]

Purpose. Mathematical and computer models development that allow counting the electricity quantity and other operating parameters of electric drives with DC motors used in home appliances. Methodology. We used known mathematical modeling methods, transient analysis in electromechanical systems and numerical solutions of nonlinear and differential equations. Findings. The dependencies between the drive operating modes, physical and mechanical properties of processed products and power consumption are obtained. The computer model developed on these relationships basis the Simulink software environment. Originality. The mathematical and computer models that allow determining the electrical power and other operating parameters of the drive by the known physical and mechanical properties of the medium, that creates a load on the working parts of the equipment, and specified operation mode, are obtained. Practical value. The calculation results using the proposed models allow us to make an informed choice of electric motors for the given conditions and the equipment operation modes. [ABSTRACT FROM AUTHOR]