Кафедра "Природничі науки"

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/1703

Увага! Поповнення колекції кафедри "Природничі науки" від травня 2023 року тимчасово призупинено.

Офіційний сайт кафедри http://web.kpi.kharkov.ua/ken

Кафедра "Природничі науки" заснована в 1973 році.

Кафедра забезпечувала викладання дисциплін природничого циклу іноземним громадянам, які готуються продовжувати навчання у вищих навчальних закладах України.

Студенти отримують необхідний рівень знань з природничих дисциплін і мають можливість вступати в будь-які вузи України для подальшого навчання.

Кафедра входить до складу Навчально-наукового інституту міжнародної освіти Національного технічного університету "Харківський політехнічний інститут".

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Adopting of DC Magnetron Sputtering Method For Preparing Semiconductor Films
(Institute of Electrical and Electronics Engineers, 2017) Kirichenko, M. V.; Zaitsev, R. V.; Dobrozhan, A. I.; Khrypunov, G. S.; Kharchenko, M. M.
It has been carried out the experimental studies of the process of cadmium telluride magnetron sputtering with direct current, and the impact of a magnetron sputtering mode on CdTe films crystalline structure. In order to create thin-film solar cells based on cadmium sulfide and telluride CdTe films for the base layers of thin film solar cells was obtained on flexible polyimide substrates by magnetron sputtering with direct current for the first time. It has found that increasing the magnetron discharge current up to 80 mA leads to increase in coherent scattering regions what is due to an increase in the thickness of the cadmium telluride films of the hexagonal modification having a columnar structure.
Advanced capacitive converters based on Al/ITO/Polyimide/Al₂O₃ heterostructures
(Vasyl Stefanyk Precarpathian National University, 2015) Zaitseva, L. V.; Khrypunov, G. S.; Zaitsev, R. V.; Momotenko, O. V.
Amplitude-time characteristics of switching in thin films of cadmium telluride
(Сумський державний університет, 2018) Khrypunov, M. G.; Zaitsev, R. V.; Kudii, D. A.; Khrypunova, A. L.
The amplitudetime characteristics of switching in thin films of cadmium telluride were investigated when single impulses of 1 μs duration are applied. It has been experimentally established that with an increase in the thickness of the cadmium telluride layer from 3 μm to 8 μm, an increase in the operating threshold from 70 V to 105 V is observed. The maximum residual sample voltage varies from 12 V to 40 V, the minimum – from 5 V to 20 V. The switching time of the samples was no more than 2 nanoseconds; the interelectrode capacity of the samples was no more than 2 pF. All the test samples were operated without failure 20 times. The structural studies of cadmium telluride films by the method of X-ray diffractometry and scanning electron microscopy have made it possible to propose a mechanism for realizing the monostable switching of the columnar structure of cadmium telluride films oriented in the form of melted high-conductivity channels in grains oriented in the direction.
Calculation of operating parameters of high-voltage power take-off system for the photovoltaic facility
(ТОВ "Друкарня "Мадрид", 2016) Zaitsev, R. V.; Kyrychenko, M. V.; Kholod, A. V.; Zaitseva, L. V.; Prokopenko, D. S.; Khrypunov, G. S.
To ensure maximum production of electric power by photovoltaic vacilities, in addition to using highly efficient photovoltaic modules equipped with solar radiation concentrators must use a highly effective power take-off system. This paper is inscribed to solving the problem of a highly efficient and economic power take-off system development. Methodology. To solving the problem, we implemented three stages. On the first stage examines the dependence of electrical power from the intensity of the incident solar radiation. Based on this, the second stage is calculated the DC-DC converter resonant circuit and its working parameters, and developed circuit diagram of DC-DC converter. On the third stage, we carry out an analysis of power take-off system with step up DC-DC converter working. Results. In this paper, we carry out the analysis of working efficiency for photovoltaic facility power take-off system with step-up boost converter. The result of such analysis show that the efficiency of such system in a wide range of photovoltaic energy module illumination power is at 0.92, whereas the efficiency of classic power take-off systems does not exceed 0.70. Achieved results allow designing a circuit scheme of a controlled bridge resonant step-up converter with digital control. Proposed scheme will ensure reliable operation, fast and accurate location point of maximum power and conversion efficiency up to 0.96. Originality. Novelty of proposed power take-off system solution constitute in implementation of circuit with DC-DC converters, which as it shown by results of carrying out modeling is the most effective. Practical value. Practical implementation of proposed power take-off system design will allow reducing losses in connective wires and increasing the efficiency of such a system up to 92.5 % in wide range of photovoltaic energy modules illumination.
Capacitive transducers based ITO/polyimide/Al2O3 thin film structure
(Національний технічний університет "Харківський політехнічний інститут", 2020) Zaitseva, Liliia; Vodoriz, Olga; Zaitsev, Roman
It has been developed and approbated prototypes of thin-film capacitor transducers based on Al/ITO/polyimide/Al2O3 heterosystem for capacitive acoustic control in metal objects in the modes of simultaneous acoustic signal reception and generation by capacitive transducers and in certain modes of acoustic signal generating or receiving that can realize objects monitoring with sensitivity at the level of piezoelectric transducers. The developed prototype of thin film capacitive transducer for monitoring pipelines by longwave capacitive method allows increasing the maximum distance between the capacitive transducers up to 10 meters. At a substrate temperature of 300 oC and a specific power of the magnetron of 0.31 W/cm2 on Upilex polyimide films were obtained layers of capacitive transducers with a thickness of 0.2-concentration of charge carriers was 8,3·1020 cm-3 and mobility - 44 cm2/(V·s). It has been engineered the thin film capacitive transducers which by using the polyamide film with 15 microns thickness of and alumina film with 1 micron thickness allow to increase the sensitivity of such method in 7-8 times, and the additional use of thin crystalline Al2O3 films deposited on a substrate of polyimide, allows to increase the value of the dielectric constant of the layer of the capacitive transduser from 3-4 relative units to 8.5-11.5 relative units. Experimental studies of the crystal structure of the developed transducers by X - ray diffractometry and research of their dielectric properties were carried out. The device was tested and the possibility of its use was shown along with the generally accepted methods of defectoscopy. It is shown that using the magnetron sputtering technology, which provides high adhesion to polyimide substrate layers, made possible produce the capacitive transducers for objects with various shape. Proposed and patented: capacitor method for receiving acoustic signals in non-destructive control and transducer of ultrasonic acoustic wave’s excitation and receiving.
Ceramics with adjustable dielectric properties based on the system SrO – TiO₂ – SiO₂
(2018) Lisachuk, Georgy; Kryvobok, Ruslan; Pitak, Yaroslav; Lapuzina, O.; Gusarova, Irina; Lisachuk, Lidiya; Grebenyuk, Andrey
This work presents the results of optimization of the compositions area of radio-absorbing ceramic. As a result of laboratory samples test, dependences "composition – property" was obtained, the choice of the most technologically advanced composition area and sintering temperature for manufacturing the radio-absorbing ceramic was substantiated. The optimal composition of the Sr- titanate ceramics is characterized by the following properties: water absorption (W = 1,3 %), dielectric permeability (ε = 115), density (ρ =4,35·10³ kg/m³).
DC magnetron sputtering method for obtaining nanoscale semiconductor films
(Інститут сцинтиляційних матеріалів Національної академії наук України, 2021) Sokol, Yevgen I.; Dobrozhan, Andrii; Meriuts, Andrey; Khrypunova, Alina
It has been carried out the experimental studies of the process of semiconductor direct current magnetron sputtering, and the impact of a magnetron sputtering mode on optical properties of solar cell functional layers. In order to create thin-film solar cells based on CdTe, thin films for the base layers of thin film solar cells was obtained on flexible polyimide and glass substrates by direct current magnetron sputtering. It has found that obtained by DC magnetron sputtering method ZnO and CdS nanoscale thin films and CdTe layers have optimal optical properties for obtaining thin film solar cells based on CdS/CdTe heterosystem.
Dependence of electrical conductivity on Bi₂Se₃ thin film thickness
(Institute for Single Crystals, 2017) Menshikova, S. I.; Rogacheva, E. I.; Sipatov, A. Yu.; Fedorov, A. G.
Effect of film thickness d on electrical conductivity σ of n-Bi₂Se₃ thin films (d = 25-420 nm) prepared by thermal evaporation in vacuum onto glass substrates was investigated. It was established that the electrical conductivity increases with increasing of the thin films thickness. The observed effect is explained as a manifestation of the classical size effect connected with diffuse scattering of electrons at the thin film interfaces. The experimental σ(d) dependence is satisfactorily described using the Fuchs-Sondheimer theory for the film thickness d > 60 nm. The specularity parameter and value of electrons mean free path are determined based of the experimental data.
Dependences of thermoelectric properties on the thickness of thin films of indium doped lead telluride
(Institute of Thermoelectricity, 2014) Menshikova, S. I.; Rogacheva, E. I.; Sipatov, A. Yu.; Matychenko, P. V.; Dobrotvorskaya, M. V.
Dependences of thermoelectric properties (the Seebeck coefficient S, the electric conductivity σ, the Hall coefficient RH, the carrier mobilityμ and the thermoelectric power P = S²·σ) on the thickness d (d = 10 – 255 nm) of thin films prepared by vacuum evaporation of indiumdoped PbTe crystals and subsequent condensation on (111) BaF₂ substrates were obtained. With decreasing thickness of films to d ≈ 40 nm, there is n- to p-type inversion of conduction which is related to a change in thermodynamic equilibrium conditions and partial reevaporation of lead and/or indium atoms. Extremes were found on the thickness dependences of properties at d₁ ≈ 20 nm which is indicative of hole gas quantization. In the range of thicknesses with n-type conduction there is a smooth change in thermoelectric properties with thickness which testifies to manifestation of classical size effect and is sufficiently well described in the framework of the Fuchs-Sondheimer theory.
Education as a key strategy of postmodern philosophy: overcoming the trauma of non‐freedom
(Харківський національний університет імені В. Н. Каразіна, 2021) Tytar, Olena Volodmyrivna; Havryliuk, Yurii Romanovych
The formation of personality attracted the attention of both classics of philosophical thought, in particular the works of C. Pierce, Z. Freud, and representatives of modern philosophical discourse (Z. Bauman, P. Ricceur, J. Hararri, K. Wilber). Recent research states that the main obstacle to formation of the individual and society is cultural trauma that arises as a result of the development of totalitarian colonial societies in the twentieth century. The concept of cultural trauma is analyzed in the studies of J. Alexander, С. Сaruth , A. Neаl. The aim is to explore the individual in modern and postmodern paradigm, the application of concepts of development, education, self‐development and self‐education of the individual in postmodern discourse, to consider education and self‐development as key strategies of postmodern philosophy in overcoming totalitarian cultural trauma. Scientific novelty. It is stated that education, development and self‐development of the individual become main strategies of information age and postmodern culture, which contributes to overcoming the totalitarian colonial traumatic experience. The personality in modern and postmodern paradigm (concepts, attitude to the personality, processes of education, social institutions, self‐education) is investigated. It should be noted that self‐development of the individual will acquire a global scale: whether it is measured by the coefficient of happiness or economic efficiency of a society, there are scientific debates, one thing is certain ‐ at the same time education, self‐education and upbringing become the deal of not individual countries, but humanity on the whole. Conclusions. 1. In the modern paradigm, the individual implicitly contains the antithesis of mental and physical origin, immutability, and hence eternity, and development as a certain adaptation of man to external circumstances of socio‐cultural life. 2. Postmodernism replaces this contradiction with the controversy or dialectic of personality as unchanging, perfect and at the same time constantly growing under the influence of both external and internal factors, the application of the concepts of self‐development and self‐education philosophical paradigm, as modern and colonial discourse seeks to do. 3. Based on the presented argumentation, the conclusion is made about education and self‐development as key strategies of postmodern philosophy in overcoming totalitarian cultural trauma of imprisonment.
Education. Science. Success
(Fort, 2021) Lapuzina, O. M.; Lisachuk, L. M.; Kudiy, D. A.
The educational guide is intended to prepare international citizens for study at universities and is designed to help them in choosing a future specialty. The manual includes: brief information that allows students to get a general idea of the structure of our university, areas of study and specialties, opportunities for scientific activity, as well as discoveries, start-ups and inventions of scientists of NTU "KhPI". The manual is intended for students and teachers of all forms of pre-university training.
The family of learner’s bilingual mathematical dictionaries
(Харківський національний університет будівництва та архітектури, 2018) Lapuzina, O.; Romanov, Yu.; Snegurova, T. A.
The foreign students training in computer science and computer ethics with the help of case-study method
(Ministerul Educatiei Cercetǎrii Universitatea “1 Decembrie 1918”, Alba Iulia, 2006) Lapuzina, O.
Generative teaching academic courses
(НТУ "ХПИ", 2016) Sladkih, I. A.; Wafic Zorkot
Guidelines to solving tasks on the topic "Mechanics" in the Physics course
(2021) Zaitseva, L. V.; Dobrozhan, A. I.; Riazanova-Khytrovska, N. V.
Methodical instructions to solving tasks on the topic "Mechanics" in the Physics course are intended for foreign students of International Education Faculty NTU "KhPI ".
High-voltage DC converter for solar power station
(Institute of advanced engineering and science, 2020) Qawaqzeh, M.; Zaitsev, R. V.; Miroshnyk, O.; Kirichenko, M. V.; Danylchenko, D.; Zaitseva, L. V.
In the article the circuit design solution of DC-DC regulated resonant converter has been proposed for using with hybrid photovoltaic modules which has cooling equipment and solar concentrators in order to maximize electric power generating by such module. By using computer simulation based on multiple iterations algorithm we significantly increase the accuracy of determining the resonance circuit optimal parameters for build up DC–DC converters to work in a wide range of electric powers. Based on optimal values of the resonance LLC scheme parameters, achived by numerical calculation it can be show high values of electrical energy transformation efficiency for photovoltaic energy station equipped with high efficiency hybrid photovoltaic modules. Implementation of microprocessor-based control into design of DC–DC back-boost converters create a new possibility to build control algorithms for increase reliability and conversion efficiency, rapid and precision stabilization of maximum power point, implementation network monitoring of photovoltaic modules, converters itself and the whole photovoltaic station parameters.
Hybrid photoenergy installation development
(2018) Zaitsev, R. V.; Kirichenko, M. V.; Krypunov, G. S.; Zaitseva, L. V.
The current problem is the autonomous supply thermal energy and hot water for civilian and military consumers. The most commonly used for this purpose are installations based on solar thermal collectors, which at the same time require an external power source up to 100 W for electronic control components and a circulating pump, which does not allow them to be fully considered as autonomous. One of the ways to solve this problem is to combine in one installation solar panels and heat collectors. It has been proposed the constructive technological solution of the hybrid photoenergy system with flexible solar cells based on cadmium telluride, which allows getting the total efficiency of such a system up to 73% for the transformation of solar energy into heat and electric energy.
Hybrid solar generating module development for high-efficiency solar energy station
(Сумський державний університет, 2018) Zaitsev, R. V.; Kirichenko, M. V.; Khrypunov, G. S.; Prokopenko, D. S.; Zaitseva, L. V.
Experimentally established, the influence of the working temperature and solar radiation power on the efficiency of industrial production silicon solar cells. Based on the experimental results designed the concept of a hybrid solar generating module equipped with a mirror concentrator of solar radiation and solar cells cooling system for using in high-performance solar energy station. Concentrator of solar radiation provides in 1.5-time increase of electrical power generating by such module, and water-cooling system can reduce the equilibrium temperature of the module up to 10 degrees and twice reduce efficiency losses from solar cells overheating. The proposed concept will reduce the number of modules needed to build solar energy station.
Improving the ecological safety of potato chips production by devising a method for wastewater treatment and recycling
(PC Technology Center, 2021) Hetta, Oksana S.; Shestopalov, Oleksii; Duhanets, Viktor; Shubravska, Olena; Rudkovskyi, Oleksandr; Paraniak, Nаdiia; Riazanova-Khytrovska, N. V.; Maksimenko, Olena
The study deals with determining the effectiveness of mechanical and physical and chemical methods for the treatment of wastewater of potato chips enterprises. It was established that the wastewater that is formed at different stages of production differ in composition. Wastewater after washing and peeling potatoes is contaminated mainly with suspended soil substances of about 500 mg/l, which are not settled, and also has soluble organic substances with a value of COD of about 1,000 mg/l. It was found that the use of coagulation-flocculation treatment makes it possible to get clear water suitable for reuse for washing potatoes. Coagulant – aluminum sulfate in the amount of 250 mg/l turned out to be effective to destroy the stability of the dispersed system. To intensify the sedimentation of coagulated flakes of suspended particles, non-ionogenic flocculant, which is recommended to be dosed after the introduction of coagulant in the amount of 2.5 ml/l, was selected. Analysis of clarified water indicates a decrease in the concentration of suspended particles up to 26 mg/l and a decrease in COD and BOD5 to values of 262 mg/l and 176 mg/l, respectively. The completed studies made it possible to propose a circuit of treatment of wastewater after washing potatoes, which consists of pre-filtering, reagent treatment, water clarification, and sediment dehydration. This circuit makes it possible to intensively clean the water to the standards of its discharge into the sewage network. However, additional disinfection of water with oxidizers, for example, ozone, was proposed for the reuse of clarified water to wash vegetables at an enterprise itself. The use of the proposed circuit of intensive water treatment will allow increasing the environmental safety of the production of potato chips by preventing environmental contamination through reducing the volume of tap water consumption.
Influence of complex activators of sintering on creating radiotransparent ceramics in SrO–Al₂O₃–SiO₂
(Технологічний центр, 2017) Lisachuk, G.; Kryvobok, R.; Zakharov, A.; Tsovma, V.; Lapuzina, O.
Досліджено вплив комплексних інтенсифікаторів спікання з числа фторидів лужних металів, а також поєднання оксидів стануму та літію на спікання стронцієвої кераміки. Показано позитивний вплив добавки SnO₂–Li₂CO₃ на низькотемпературну активацію процесу синтезу стронцієвого анортиту і отримання щільноспеченого керамічного матеріалу. Встановлено, що за своїми діелектричними властивостями отриманий керамічний матеріал може бути віднесений до радіопрозорих матеріалів.