Academic literature on the topic 'Massive electrically conductive armature'

At present, on the territory of the Russian Federation, there is no massive use of electrically conductive reinforced concrete structures in the electric power industry due to insufficient operating experience and a low rate of research on electrically conductive concretes. The article compares the main characteristics of existing electrically conductive concrete. The paper shows the disadvantages of traditional concrete and existing electrically conductive concrete. The electrically conductive concrete was selected, the most suitable for further research, testing and direct modernization of the composition based on the results obtained. The main disadvantages of existing electrically conductive concretes are the high cost and specificity of electrically conductive components and other additives, as a consequence of the amount of capital investment in mass and large-scale production, as well as the lack of operating experience as overhead supports.

Recently, conductive fabric has attracted massive attention among researchers due to their unique conductive properties with a wide range of possible applications. This study explores the fabrication of poly aniline (PANI) conductive fabric through an immersion technique of polyester fabric in PANI solution. Two types of acids (sulphuric acid (H2SO4) and p-toulene sulfonic acid (pTSA) have been employed as the doping agent to induce the conductivity in various weight percentages (0.3, 0.6 and 0.9 wt%) with immersion time of 5, 10 and 15 minutes. The fabricated conducting fabrics were then characterized by Fourier Transform Infrared Spectroscopy with attenuated total reflection (FTIR-ATR) and X-ray Diffraction (XRD) for analyses of chemical structure and phase identification respectively. Their morphologies were observed by Scanning Electron Microscope (SEM) which revealed the various fibrous structure. The finding is in line with the electrical conductivity properties of the fabrics observed using Four-point probe technique. Optimum conductivity of the conductive fabrics were found to be at 0.6 wt. % for both types of acid which are 1.30 x 10-2 S/cm (H2SO4) and 1.39 x10-3 S/cm (pTSA). Meanwhile, the varied immersion time showed no significant changes on this property, due to the short time laps. For FTIR results, the peaks confirmed the presence of PANI-EB together with the introduced acid within the PANI backbone. Collectively, H2SO4 is found to be a good candidate as doping agent, deduced from obtained conductivity values and structural properties.

Aim: The goal is to present a new asynchronous principle of operation of stepper motors, based on the use of counter-rotating (or traveling) magnetic fields. Method: A change in the degree of symmetry of one of these magnetic fields leads to the fact that the armature (rotor or secondary element) makes a precise discrete movement. Result: The force moving the armature of a stepper induction motor is created as a result of the interaction of eddy currents in the armature with a rotating or traveling magnetic field. Stepper induction motors can rotate the rotor at a certain angle and discretely move flat or cylindrical electrically conductive armatures, which can be smooth and non-magnetic. A separate group of motors for a discrete electric drive is made up of two-coordinate linear stepping asynchronous machines, which also operate using the same counter-running magnetic fields both in the longitudinal and transverse directions. Conclusion: The features of the design of such electric machines are presented, the values of the magnetic induction in different zones of a two-coordinate stepper motor are determined, the relations for calculating the steps of the armature in both the longitudinal and transverse directions are given.

This letter presents the results of the mathematical modeling of processes of electrically conducting fluid flow dynamics for complex heat transfer systems. The study was carried out based on detailed calculations on parallel high performance computational systems on the basis of the kinetically consistent magnetogasdynamic approach, adjusted for this class of problems. The kinetically consistent algorithm adapts well to the architecture of high performance computational systems with massive parallelism and makes it possible to conduct effective research of complex heat transfer systems with high resolution. The article presents the approach, method and algorithms as well as the results of the mathematical modeling.

The surface stress of a metallic solid-body immersed in an electrolyte can be modified by variation of an applied electrical potential. The stress at the surface is transferred to the underlying bulk material, where it leads to strain and, hence, electrochemical actuation. For massive bodies, which exhibit a small ratio of surface to volume atoms, this effect is sparsely pronounced and not usable. Nanoporous metals on the other hand exhibit a high intrinsic, externally accessible surface area and are therefore suitable as functional materials such as sensors or actuators. Another class of chemo-mechanical actuators are electrically conductive polymers, which swell or shrink through the potential-controlled incorporation or removal of anions. Fast ion exchange is possible with thin layers, yet the stiffness of supporting substrates limits their effect for actuation. The combination of both approaches via coating of the inner surface of nanoporous gold with polypyrrole results in a hybrid material with significantly improved electrochemical and actuatoric properties. This contribution focuses on the manufacturing of hybrid materials consisting of nanoporous gold and electrically conductive polymers, its chemo-mechanical properties as well as the underlying electro-chemo-mechanical coupling mechanisms.

The self-potential (SP) method detects naturally occurring electric fields, which may be produced by electrically conductive mineral deposits, such as massive sulfides. Recently, there has been increasing interest in applying this method in a marine environment to explore for seafloor massive sulfide (SMS) deposits, which may contain economic resources of base and precious metals. Although SMS sites that are associated with active venting and are not buried under sediment cover are known to produce an SP signal, the effectiveness of the method at detecting inactive and sediment-covered deposits remained an outstanding question. We built an instrument capable of recording SP data in a marine setting. We carried out a test of the instrument at the Palinuro Seamount in the Tyrrhenian Sea. Palinuro is one of only a few known sites containing an SMS occurrence that is buried under sediment and not associated with active hydrothermal venting, although diffuse seepage of hydrothermal fluids is known to occur at the site. Elevated electric field strengths recorded in and near the site of previously drilled massive sulfide samples are on the order of [Formula: see text]. A second zone of high field strengths was detected to the north of the drilling area where gravity coring later confirmed the existence of massive sulfides. Our observations indicate that an SP signal can be observed at the site of SMS mineralization even when the mineralized zone is shallowly buried and active hydrothermal venting is not present. These observations could aid in the planning of future marine research expeditions that use the SP method in the exploration of seafloor massive sulfides.

Background: Helicobacter pylori, which infects at least half of the human population, is an etiopathogenetic factor in the development of chronic gastritis (CG), gastric and duodenal ulcer disease (UD), and is also considered a risk factor in the occurrence of some forms of stomach cancer. Various surface structures of H. pylori are important pathogenic factors. Methods: Reference (NCTC 11637, NCTC 11639) and freshly isolated H. pylori strains as well as samples of the gastric mucosa were examined using transmission (TEM) and scanning electron microscopy (SEM) by means of “JEM-100 В” (JEOL, Japan) and “Quanta 200 3D” (FEI Company, USA) systems, respectively. Samples for SEM fixed with formalin and not subjected to dehydration were sprayed with an electrically conductive layer of gold. Samples for TEM were prepared using negative contrast (NC) with ammonium molybdate and ultrathin sections (US) contrasted by Reynolds; fixation by Ito-Karnovsky was used in both cases. Accelerating voltage at TEM and SEM was 80 and 10 kV, respectively. Results: Three types of H. pylori surface structures were found: flagella, fimbria, and vesicles. Flagella were found both in the material of cultures maintained in vitro and in each native sample of the gastric mucosa. SEM images suggest the involvement of flagella in biofilm formation. On longitudinal sections of the flagellum, the outer electron-dense layer and the inner content in the form of a filament were visualized; on cross sections, the flagellum looked like an annular structure with a centrally located point accumulation of electron-dense matter. Paradoxically, the H. pylori forms with a defective cell wall also possessed flagella. Freely located flagellar sheaths without central filament were often found in vitro only. Fimbriae were found exclusively in negatively contrasted pure bacterial cultures material. In addition, vesicles detaching from the surface of bacterial cells were found both in the material of aging H. pylori pure cultures and in native samples of the gastric mucosa under CG and UD. A small part of the vesicles retains their connection with the cell wall, while detached vesicles are present in excess in the surrounding space. Massive detachment of vesicles leads to the formation of spheroplasts, devoid of an outer membrane. Conclusion: H. pylori has a representative set of surface structures that play an important role in the onset and development of the infectious process in the gastroduodenal area.

Electrical energy generation is essential for the survival of the modern society. Fossil fuels are limited and create pollution. Also the conventional power generation systems using fossil fuel have lesser efficiency due to higher amount of losses in different sections of the plants. The Magnetohydrodynamic (MHD) is found as a nonconventional energy generation system which has the capability to enhance the thermal power plant efficiency significantly. The MHD is a direct energy conversion system that describes the interactions of a magnetic field and an electrically conductive fluid to produce electrical power. The system is simple and it avoids the difficulty of choosing a rotating turbine or engine and massive number of complex calculations. The high temperature tolerable materials can be used in the system due to the exponential development of material science. In MHD system, energy of plasma or ionized gas is directly converted into electric power. The conversion process of the system is based on the principle of Faraday’s Laws of electromagnetic induction and fluid dynamics. The MHD generator uses hot conductive ionized gas or plasma as the moving conductor whereas in the mechanical dynamo, in contrast, uses the motion of mechanical devices to accomplish this. Seeding materials such as potassium carbonate, potassium sulphates are used to enhance the conductivity of the ionized gas. The focus of the present study is to investigate alternative methods through which an MHD power generator can be coupled to the existing gas turbine and steam plants. In doing so, the thermal cycle efficiency of these conventional plants can be improved. A case study is also presented to calculate the power output and efficiency in a simple way.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.09.01 "Електричні машини й апарати" (14 – Електрична інженерія) – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2020 р. Дисертаційна робота присвячена удосконаленню лінійних імпульсних електромеханічних перетворювачів силового та швидкісного призначення за рахунок використання декількох якорів, що взаємодіють з обмоткою індуктора. В дисертаційній роботі проведено аналіз конструкцій та сфер використання лінійних імпульсних електромеханічних перетворювачів індукційного, електромагнітного та електродинамічного типів в якості ударно-силових та прискорювальних пристроїв. Реалізовано в програмному середовищі COMSOL Multiphysics математичну модель лінійного імпульсного електромеханічного перетворювача мультиякірної конфігурації, яка враховує взаємопов’язані електричні, магнітні, механічні і теплові процеси, нелінійні магнітні та теплофізичні залежності. Розроблено класифікацію електромеханічних перетворювачів, які включають феромагнітний, котушковий та суцільний електропровідний якоря. Встановлено особливості протікання електромагнітних процесів та визначені електричні, магнітні та силові показники електромеханічних мультиякірних конфігурацій. Запропоновано комплексний критерій оцінювання ефективності, за допомогою якого проведено порівняльний аналіз перетворювачів мультиякірних конфігурацій з перетворювачами, що мають один якір. Встановлено вплив форми струму збудження на ефективність перетворювачів мультиякірних конфігурацій. Проведено експериментальні дослідження електромеханічних перетворювачів силового та швидкісного призначення з одночасним вимірюванням електричних, магнітних механічних та теплових параметрів. На базі електромеханічних перетворювачів мультиякірних конфігурацій розроблено оригінальні конструкції та випробувано моделі електромагнітної катапульти для БПЛА, магнітно-імпульсного пресу для керамічних порошкових матеріалів, електромеханічного пристрою для скидання ожеледних і снігових відкладень з проводу лінії електропередачі та пристрою для знищення інформації на твердотільному цифровому SSD накопичувачі.
The dissertation for the degree of Candidate of Technical Sciences in the specialty 05.09.01 “Electric machines and apparatus” (14 - Electrical Engineering) - National Technical University “Kharkov Polytechnic Institute”, Kharkov, 2020. The dissertation is devoted to the improvement of linear pulsed electromechanical converters due to multi-dia configurations. In the dissertation work the analysis of designs and spheres of use of linear pulse electromechanical converters of induction, electromagnetic and electrodynamic type as shock-power and accelerating devices is carried out. Developed and implemented in the COMSOL Multiphysics software environment, a mathematical model of linear pulse electromechanical converters multi-core configuration, which takes into account the interconnected electrical, magnetic, mechanical and thermal processes, nonlinear magnetic and thermophysical dependences. The classification of electromechanical converters which includes ferromagnetic, coil and massive electrically conductive anchors is developed. The peculiarities of the course of electromagnetic processes are established and the electrical, magnetic and power indicators of electromechanical converters of multi-core configurations are determined. A complex criterion for evaluating the efficiency is proposed, by means of which a comparative analysis of electromechanical converters of multicore configurations with electromechanical converters having one anchor is carried out. The influence of the form of excitation current on the efficiency of electromechanical converters of multicore configurations is established. The method is developed and experimental researches of electromechanical converters of power and speed appointment with simultaneous measurement of electric, mechanical and thermal parameters are carried out. On the basis of electromechanical converters multi-core configurations, original designs of electromagnetic catapult models for UAVs, magnetic-pulse press for ceramic powder materials and electromechanical device for discharge of ice and snow deposits from the power line wire were developed and tested.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.09.01 "Електричні машини й апарати" (14 – Електрична інженерія) – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2020 р. Дисертаційна робота присвячена удосконаленню лінійних імпульсних електромеханічних перетворювачів за рахунок мультиякірних конфігурацій. Для досягнення цієї мети були поставлені задачі: – провести аналіз конструкцій та сфер використання лінійних імпульсних електромеханічних перетворювачів індукційного, електродинамічного і електромагнітного типів в якості ударно-силових та прискорювальних пристроїв; – реалізувати в програмному середовищі COMSOL Multiphysics математичну модель лінійного імпульсного електромеханічного перетворювача мультиякірної конфігурації, яка враховує взаємопов’язані електричні, магнітні, механічні і теплові процеси та нелінійні магнітні і теплофізичні залежності; – провести аналіз електромеханічних характеристик лінійних імпульсних електромеханічних перетворювачів мультиякірних конфігурацій та за допомогою комплексного критерію оцінити їх ефективність; – встановити вплив форми струму збудження на ефективність лінійних імпульсних електромеханічних перетворювачів мультиякірних конфігурацій; – провести експериментальні дослідження лінійних імпульсних електромеханічних перетворювачів, запропонувати та випробувати моделі електромагнітної катапульти для безпілотного літального апарату, магнітно-імпульсного пресу для керамічних порошкових матеріалів, електромеханічного пристрою для скидання ожеледних та снігових відкладень з проводу лінії електропередачі та пристрою для знищення інформації на SSD накопичувачі. Об’єкт дослідження – електромеханічні процеси та показники лінійних імпульсних електромеханічних перетворювачів мультиякірних конфігурацій. Предмет дослідження – лінійні імпульсні електромеханічні перетворювачі мультиякірних конфігурацій силового та швидкісного призначення. Методи дослідження. При розв’язанні поставлених задач використовувалось математичне моделювання електромагнітних, механічних та теплофізичних процесів в лінійних імпульсних електромеханічних перетворювачах імпульсної дії для проведення аналізу електромеханічних характеристик та встановлення впливу форми струму збудження на ефективність перетворювачів. Експериментальні дослідження лінійних імпульсних електромеханічних перетворювачів мультиякірної конфігурації проводились на експериментальних стендах, що дозволило випробувати моделі пристроїв. В роботі отримані такі наукові результати: – отримала подальший розвиток класифікація лінійних імпульсних електромеханічних перетворювачів мультиякірних конфігурацій, які включають феромагнітний, котушковий та суцільний електропровідний якоря; – удосконалено математичну модель лінійного імпульсного електромеханічного перетворювача за рахунок включення феромагнітного, котушкового та суцільного електропровідного якорів, які взаємодіють з рухомим якорем. Математична модель, яка реалізована в програмному середовищі COMSOL Multiphysics, містить взаємопов’язані електричні, магнітні, механічні та теплові процеси і враховує магнітні та теплофізичні нелінійні залежності; – вперше встановлено особливості протікання електромагнітних процесів та визначено електричні, магнітні та силові показники лінійних імпульсних електромеханічних перетворювачів мультиякірних конфігурацій силового призначення. Показано що практично всі перетворювачі мультиякірних конфігурацій забезпечують збільшення амплітуди та величини імпульсу електродинамічних зусиль у порівнянні з перетворювачем, що має один суцільний електропровідний якір; – вперше встановлено вплив геометричних параметрів рухомого і нерухомого електропровідних якорів, які взаємодіють з рухомим індуктором, що дозволило підвищити швидкісні показники лінійного імпульсного електромеханічного перетворювача; – вперше встановлено, що при збуджені коливально-загасаючою, аперіодичною та аперіодичною з підживленням формами струму в перетворювачах мультиякірних конфігурацій величина імпульсу електродинамічних зусиль збільшується у порівнянні з перетворювачем, що має один суцільний електропровідний якір. Дисертаційна робота виконана в НТУ "ХПІ" і є частиною науково-дослідних робіт кафедри загальної електротехніки. Робота виконувалися за держбюджетними темами "Розробка засобів підвищення ефективності лінійних ударних електромеханічних прискорювачів та силових пристроїв" (ДР № 0115U000522) і "Удосконалення технічних систем та пристроїв за рахунок імпульсних електромеханічних перетворювачів та електрофізичних технологій" (ДР № 0117U004881), госпдоговірної теми № 15812 "Розробка та дослідження високошвидкісного електродинамічного приводу" і ініціативної теми "Сучасні проблеми та перспективи розвитку електротехнічних пристроїв та систем" (ДР № 0119U002551), де автор був співвиконавцем.
Dissertation for Candidate of Science Degree in Specialty 05.09.01 "Electrical Machines and Apparatuses" (14 – Electrical Engineering) – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2020. The dissertation work is devoted to the improvement of linear pulse electromechanical converters due to multi - core configurations. To achieve this goal, the following tasks were set: – to analyze the structures and areas of use of linear pulse electromechanical converters of induction, electrodynamics and electromagnetic types as shockpower and accelerating devices; – to implement in the COMSOL Multiphysics software environment a mathematical model of a linear pulse electromechanical converter of multi-core configuration, which takes into account the interconnected electrical, magnetic, mechanical and thermal processes and nonlinear magnetic and thermophysical dependences; – to analyze the electromechanical characteristics of linear pulse electromechanical converters of multicore configurations and to evaluate their efficiency with the help of a complex criterion; – to establish the influence of the shape of the excitation current on the efficiency of linear pulse electromechanical transducers of multicore configurations; – to conduct experimental studies of linear pulse electromechanical transducers, to propose and test models of electromagnetic catapult for unmanned aerial vehicle, magnetic pulse press for ceramic powder materials, electromechanical device for discharging ice and snow deposits from the transmission line wire and transmission line. Object of research – electromechanical processes and indicators of linear pulse electromechanical converters of multicore configurations. Subject of research – linear pulse electromechanical converters of multicore configurations of power and speed purpose. Research methods. Mathematical modeling of electromagnetic, mechanical and thermophysical processes in linear pulse electromechanical converters of pulse action was used to solve the tasks to analyze the electromechanical characteristics and establish the influence of the shape of the excitation current on the efficiency of the converters. Experimental studies of linear pulse electromechanical transducers of multicore configuration were performed on experimental stands, which allowed to test device models. The following scientific results are obtained in the work: – the classification of linear pulse electromechanical converters of multicore configurations, which include ferromagnetic, coil and continuous conductive armature, was further developed; – the mathematical model of the linear pulse electromechanical converter due to inclusion of the ferromagnetic, coil and continuous electrically conductive anchors which interact with a mobile anchor is improved. The mathematical model, which is implemented in the COMSOL Multiphysics software environment, contains interconnected electrical, magnetic, mechanical and thermal processes and takes into account magnetic and thermophysical nonlinear dependencies; – for the first time the peculiarities of the course of electromagnetic processes are established and the electrical, magnetic and power indicators of linear pulse electromechanical converters of multi-core configurations of power purpose are determined. It is shown that almost all converters of multi-arc configurations provide an increase in the amplitude and magnitude of the pulse of electrodynamics forces in comparison with the converter, which has one continuous conductive armature; – for the first time the influence of geometrical parameters of movable and fixed electrically conductive armatures that interact with the movable inductor was established, which allowed to increase the speed indicators of the linear pulse electromechanical converter; – for the first time it is established that when excited by oscillatingattenuating, aperiodic and aperiodic with feeding forms of current in converters of multicore configurations the magnitude of the electrodynamics force pulse increases in comparison with the converter having one continuous electrically conductive armature. The dissertation work was performed at the National Technical University "Kharkiv Polytechnic Institute" and is part of the research work of the Department of General Electrical Engineering. The work was carried out on the basis of financing by state budget topics: "Development of means of increasing the efficiency of linear shock electromechanical accelerators and power devices" (DR №0115U000522), "Improvement of technical systems and devices by means of impulse electromechanical converters. (DR № 0117U004881), the contractual theme "Development and research of high-speed electrodynamics actuator" (at the expense of LLC "TETRA, Ltd", Kharkiv), and the initiative theme "Modern problems and prospects for the development of electrotechnical devices and systems" (DR №0119U002551) where the author was a co-author.

Today, 3D printing is taking its constantly growing part in a lot of different manufacturing industries, educational institutions and a lot of entrepreneurship and home businesses. Besides prototyping and proof of concept, utilization of 3D printing is undoubtedly spreading its roots in manufacturing of production and spare parts but also in aiding research and teaching processes. 3D printing has reinforced the self-employed segment of market called makers but also has influenced forming a significant number of educational online video channels. A lot of crowdfunded web sites promote affordable desktop 3D printers and 3D modellers and designers who design models exclusively for 3D printing, taking its specificity into account. Also, a community of designers, through 3D printing hubs where their work can be purchased, are thriving. There is also a massive trend in developing new materials for 3D printing such as electrically conductive composites, fire-resistant materials and materials with high strength or resilience. In the graphic industry, there is some progress regarding the utilization of 3D printing in the form of tactile maps and picture books, manufacturing customizable packaging, embossing tools, making parts for colour measuring equipment and printing of textiles. However, there is undoubtedly undiscovered usage intended for improvements in this branch of industry. The first part of this research aims to present existing researches and projects regarding the usage of 3D printing in creative and interdisciplinary industries such as graphic industry. The second part of this paper focuses on different initiatives in aiding educational process worldwide, and some of the methodology of implementing 3D printing in education. In the final part of this research, the potential of 3D printing for educational purposes of graphic engineering and design students is discussed. Methodology for getting theoretical and practical knowledge is proposed through a designed catalogue of 3D printing parameters. The purpose of this catalogue is to introduce undergraduate students with one of the most used and affordable 3D printing technique known as Fused Deposition Modelling (FDM) and to provide them with basic knowledge of 3D printing parameters which further on can be expanded and supplemented.