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The possibility of direct current measuring converters construction measuring converted direct current, realizing straightdirect current-to-frequency conversion of current into frequency of alternating current or voltage is considered. An oscillistor made of electronic germanium is used as an element realizing this conversion. The dependences of frequency on current obtained in the course of theoretical and experimental studies are given. The device of the current-frequency converter is shown and its characteristics are given.

A new method for measuring electric field strength is proposed. The method is based on the mean value measurement method, which uses a dual electroinduction spherical sensor. The use of the dual sensor for the method implementation allows to extend the functionality of the method by mean value. The method of measurement by the mean value assumes simultaneous measurement of two values of intensity E1 and E2 in one point of electric field with opposite sign errors. As the theory of construction of the new method has shown, it is possible to determine not only the measurement result as an average of two values of the strengths, but also to estimate the error of the measurement result and tentatively determine the distance to the field source. In order to determine the distance to the field source, a coefficient of the ratio of the two found strengths at each point of the field is introduced, by which the empirical dependence of the relative distance to the field source is found. The relative distance is the ratio between the radius of the spherical sensor and the distance to the field source. By determining the relative distance at each measuring point according to this relationship and substituting it into the known expression for the error, the error of the result at the measuring point is determined. The relative distance is also used to determine the distance to the field source. Thus, the new method of measurement allows to increase the accuracy of measurement of electric field strength, determined by the relative distance to the source of the field.

The purpose of this Erratum is to correct a misprint presented in the original article.

The electric field strength is one of the main factors influencing sensitive microprocessor equipment and personnel on power stations and substations, power lines. Determining its level is an important applied task for ensuring the safe operation of electrical installations. The aim is to develop calculation relationships for determining the electric field strength created by the busbar of high-voltage substations in the working areas of personnel. The solution of the problem was based on the use of the method of equivalent charges to determine the strength of the electric field created by the complex busbar of high-voltage substations. Methodology. The development was based on solving the problem of the potential of the electric field of a point charge located in a dielectric half-space for a cylindrical coordinate system. By representing the electrode in the form of a set of point charges and subsequent integration, an expression for calculating the potential is obtained, created by a busbar of arbitrary orientation of finite length in an analytical form. Using the principle of superposition of fields and the definition of the derivative, expressions were obtained for calculating the vertical component of the electric field strength at given heights. Results. Based on the obtained expressions, using Visual Basic, the simulation of the distribution of the electric field strength under a three-phase power line with a voltage of 150 kV was performed. Comparison with the known calculation results obtained on the basis of analytical expressions for infinitely long conductors showed that the obtained expressions have an error of no more than 7%. The scientific novelty lies in the fact that for the first time expressions were obtained for determining the electric field strength created by a system of electrodes of finite length, based on the analytical method for solving differential equations. Practical significance. The proposed technique is implemented as a test module of the LiGro specialized software package, which allows modeling complex busbar systems typical for power stations and substations and power lines. A test calculation was carried out for an operating substation of regional electric networks with a voltage class of 110 kV. By comparing the duration of the calculation of switchgears with a diagonal of about 500 m, it was found that the calculation time in the LiGro complex based on the analytical method is several tens of times less than the calculation based on the finite element method. In addition, a more powerful computer was used for the end element simulation.

Tasks related to the protection of biological and technical objects from the effects of electrical are relevant. One of these tasks is related to the development of electric field strength sensors with specified metrological characteristics. The aim of the study is to minimize the error of the known sensor and expand its spatial measurement range due to the rational choice of sensitive elements. The sensor proposed in the work has a negative error  from the field inhomogeneity modulo no more than 3 % in the spatial measurement range 0aR, where R is the radius of the disk base of the sensor. To ensure the required metrological characteristics of the sensor, rational dimensions of its sensitive elements are selected. In this case, the rational radius r of the sensing elements made in the shape of a circle must satisfy the condition r

The research carries out a spatial model of path tracking using the dynamic parameters of the object's position, as well as the path of motion of electric field source. The simulation results show high accuracy in estimating the dependence between the electric field components and position modifications. The results are in good agreement with the results of FEM analysis. The connection between the measurement error of the electric field component, horizontal angle, location angle, and tracking accuracy is also used to analyze the tracking performance. In addition, the method can be combined with spatiotemporal coordinates, in which case the configuration becomes appropriate to the current conditions while maintaining maximum efficiency of the estimation system as a whole and allows predicting changes in the position of the object as a field source.

The problem of a convectional instability in a horizontal dielectric fluid layer with electric field modulation under couple stress fluid is examined. The horizontal dielectric upper boundary fluid layer is cooled, and the lower boundary is subjected to an isothermal boundary condition. The regular perturbation method based on the small magnitude of modulation is used to compute the critical Rayleigh number and the corresponding wavenumber. The solidity of the system is the characterised by a correction Rayleigh number, which is computed as a function of thermal, electric, and couple stress parameters and the frequency of electric field modulation. Some of the known findings are retrieved as specific cases in this study. It is demonstrated that the onset of the convection may be advanced or delayed by the proper regulation of different regulation parameters. The outcomes of this study have potential implications for the control of electroconvection with a time-dependent electric field.

Background. Quantum dots (QDs) have unique optical properties that have found wide applications in optoelectronics, biology and medicine. The problem of controlling the spectral – luminescent properties of QDs initiated studies of the mechanisms of interaction of QDs with each other and with the surrounding matrix. Such interactions, under certain conditions, can significantly modify the radiative properties of QDs, which will affect the characteristics of laser structures and biosensors based on them. The purpose of this work is to study the effect of 2D dissipative tunneling in the QDs - surrounding matrix system, as well as the paired electrostatic interaction of QDs with (А+ + е) impurity complexes, on recombination radiation associated with the optical transition of an electron from the ground state of QDs to a quasi-stationary A+ state in the external electric field. Materials and methods. The interaction of an electron in the ground state of the QDs and a hole localized at the A+ center was considered in the framework of the adiabatic approximation. The dispersion equations determining the dependence of the binding energy of a hole in an impurity complex (А+ + е) in a spherically symmetric QDs on the magnitude of the external electric field and the parameters of dissipative tunneling are obtained within the framework of the zero radius potential model, in the approximation of the effective mass. The spectral intensity of recombination radiation (SIRI) in QDs with an impurity complex (А+ + е) in an external electric field is calculated in the dipole approximation. The effect of the electric field on the ground state of the electron in the QDs was taken into account in the second order of the perturbation theory. Numerical calculations and plotting of graphs were carried out for InSb-based semiconductor quantum dots using symbolic mathematics Mathcad 14 and Wolfram Mathematica 9. The probability of 2D dissipative tunneling was calculated with exponential accuracy for a model 2D oscillatory potential at a finite temperature, taking into account linear interaction with phonon modes of the environment at one time instanton quasi-classical approximation. Results. It is shown that the field dependence of the binding energy of the quasi-stationary A+ state has an oscillating character associated with quantum beats that occur during parallel 2D tunneling transfer. It is found that the SIRI curves have a characteristic fracture corresponding to the 2D bifurcation point that occurs when the tunneling modes in the interacting QDs pair change from synchronous to asynchronous. It is established that in the vicinity of the 2D bifurcation point there are irregular oscillations in SIRI associated with the modes of quantum beats when competing trajectories of tunnel transport appear. It is found that the parameters of dissipative tunneling: temperature, frequency of the phonon mode, the constant of interaction with the contact medium, the constant of interaction of QDs, have a significant effect on the amplitude of quantum beats and the position of the 2D bifurcation point in SIRI. Conclusions. Taking into account the interaction of QDs with the surrounding matrix leads to a significant modification of SIRI, which manifests itself in the form of bifurcation points and quantum beats depending on the parameters of dissipative tunneling. Taking into account the paired interaction of QDs with each other by means of hole pushing in (А+ + е) complexes leads to the suppression of recombination radiation with an increase in the constant interaction.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work is devoted to the study of the laws governing the deposition of particles of the dispersed phase of an electrically charged dusty medium moving in a channel onto an electrode plate. The aim of the study is to reveal the influence of the size of dispersed inclusions and the density of the material of particles on the process of settling of fractions of a polydisperse gas suspension on the surface of the electrode plate. When modeling the dynamics of a gas suspension, a mathematical model of the motion of a multi-speed and multi-temperature polydisperse two-phase medium was used, taking into account the interphase force interaction and interphase heat transfer. When describing the force interaction, the Stokes force was taken into account. The mathematical model of the dynamics of a two-phase medium was supplemented with boundary conditions. The system of equations was solved by the McCormack explicit finite-difference method having the second order of accuracy. To obtain a monotonic numerical solution, a grid function correction scheme was applied. For the potential of the electric field on the lateral surfaces, the values of the potential were determined; at the open ends of the channel for the potential of the electric field, uniform Neumann boundary conditions were assumed. The paper considered gas suspension, the dispersed phase of which contains three fractions. At the same size, the gas suspension fractions differed in the material density of the particles of the fractions. At the same density of the material of particles, the fractions of the solid phase of the gas suspension had different sizes of dispersed inclusions. As a result of numerical modeling, it was revealed how the density of the material of the dispersed phase and the size of the particles affect the process of precipitation of fractions of the dispersed phase of the two-component mixture. From calculations it follows that with the same particle size, particles with a higher density of the material are deposited more intensively, and with the same density of the particle material, particles with a large linear size are deposited more intensively.

Introduction. Periodic geodetic observations are used to control the position of building structures and soil massifs. Since tilt is considered to be one of the most dangerous types of building deformations, this paper considers existing methods for its determination. When a horizontal displacement (tilt) is detected, it is of particular importance to assess not so much its angle but its direction. This allows preventive measures to be timely enforced. Therefore, determination of the direction of horizontal displacements at small tilt angles presents a relevant research problem. In order to increase the sensitivity of the considered measuring device, it is proposed to use the action of electric field.Aim. Calculation of electrical voltages that ensure reliable operation of the device under consideration, depending on its geometric dimensions and characteristics of the materials used.Materials and methods. The device was made of conductive, semiconductive and dielectric materials. Calculations were based on an analysis of forces acting on a vertically suspended load in the presence of electric field. The conditions of equilibrium and instability of the position of the load arising due to strong positive feedback in electric field were considered.Results. Calculations were performed to support a reasonable choice of geometric and electrophysical characteristics of the developed device. A formula was obtained for the values of electrical voltages that could ensure troublefree operation of the device. The calculated values of operating voltages were found to be acceptable for practical application. The main structural elements of the device and one of the possible methods for registering information signals were proposed.Conclusion. Due to the instable position of the load in a sufficiently strong electric field, the developed device allows the direction of displacements to be measured even when their values tend to zero. This makes the developed device promising for practical application. However, it should be noted that, under such small displacements, the accuracy of the device depends on the manufacturing conditions and random factors.

The paper considers the degree of fractal structure impact on the electric field intensity inside thunderstorm clouds using the apparatus of fractional integrodifferentiation. We propose a mathematical model of intensity dynamics of a static electric field in the thunderstorm clouds, taking into account media with fractal dimension. The results obtained confirm the close connection of electrophysical processes in thunderclouds with the fractal medium itself.

Some methods for determining small angular deviations have been considered on the example of building objects. The design of an electrostatic cylindrical sensor was put forward, and the use of force action of an electric field was proposed in order to increase the sensitivity of the sensor. The main structural elements of the sensor are a plumb-line weighted at one end and a cylinder surrounding it. The conditions of equilibrium and instability of the position of the plumb arising due to positive feedback in the electric field were considered. An estimated calculation of the time of movement of the plumb until the moment of its touching the inside of the cylinder was made. The calculation result could be taken as a starting point for finding the desired angular deviation. The inaccuracy in the manufacture of the device and the random factors were noted to become influential at small deviations. The paper proposed some ways to solve these problems.

Background and Objectives: Here, non-thermal effects induced in the suspension of hollow alginate silver microcontainers after application of short electric field pulses (about 1 ms) of high intensity (about 1 kV/cm) were studied as a prospective tool for remote activation of microcontainers. Alterations in microcontaner’s shells were studied as a function of their composition. Magnetic nanoparticles immobilized within microcontainer’s shells were found to enhance effects that occurred after application of electric field pulses. Alterations found in microcontaner’s shells can be further employed for remote activation of microcontainers and release of encapsulated cargo. Results: The obtained results are the basis for further research of multifunctional microcontainers based on an organic alginate matrix and inorganic metal nanoparticles of silver and magnetite as drug carriers, the permeability, and structure of which can be switched using a non-thermal pulsed electrical action. Conclusion: The proposed microcontainers can be employed as carriers in new effective systems for encapsulation, targeted delivery, and controlled release of various substances in aqueous media responsive towards electric and magnetic fields which are promising in a wide range of biomedical tasks and other applications.

The relevance. Determination of the main electrical parameters of oil submersible cables is associated with the need to create accurate mathematical models of the systems control station – oil submersible cable – submersible motor, in which it is necessary to take into account wave processes in a long cable line arising in connection with the shape pulses generated by frequency converters included in the set of modern control stations. Electrical parameters such as linear capacities and inductances are not standardized in the technical literature and are not indicated in the technical specifications by cable manufacturers. However, it is obvious that the creation of control systems and identification of the SEM operation modes requires the solution of systems of differential equations, which include the specified characteristics as parameters. In addition, modern concepts of frequency control of electric motors, in particular submersible, indicate that during operation of frequency converters based on IGBT transistors, high-frequency overvoltages arise in the SEM supply signal, leading to the appearance of partial discharges in the stator windings of the motors. This fact will be aggravated by the development of deeper fields, with a longer cable length and, accordingly, a greater influence of wave processes on the shape of the signal supplied to the SEM. The main aim of the research consists in development of a method for determining the linear electrical parameters of the submersible cable of any designs and materials used. Methods: methods for solving differential equations, field problems, numerical finite element modeling, and a physical experiment. Results. A method was developed for determining the linear capacities and inductances of conductors and armor of an oil-submersible cable, based on solving differential equations for a «reference» model, numerical modeling of an identical design in COMSOL Multiphysics® Version 5.5a, comparison of the obtained values ​​with experimental data. It is indicated that the finite element modeling in COMSOL Multiphysics® Version 5.5a is correct and with sufficient accuracy (error less than 5 %) coincides with the results of solving the equations given in the reference literature. The linear values ​​of capacities and inductances have been determined for the most common designs of oil-submersible cables.

Testing of electronic devices is an integral part of the technological process of any manufacturer of such equipment. In this case, an electronic device is understood as an energy-intensive unit such as a mobile phone, data center or spacecraft. One of the key stages of testing is to identify the effect of electric fields on various electronic components of the device. This stage often requires making a mock-up of some part of an unfinished device in order to fix interference with special equipment. This requires time, financial and human resource costs. In order to reduce these costs in the modern world, the use of mathematical modeling tools for testing noise immunity and electromagnetic compatibility is becoming popular. In this paper, it is proposed to use an algorithm for visualizing electric fields in three-dimensional space and time. The algorithm is easily embedded into applications as a component of a mathematical modeling system. The work considered three ways of visualizing the electric field strength: starting from a simple setting of points in space, on the basis of which the electric field will be built, around the source of electric field radiation, to the use of algorithms that make it possible to arrange points equidistantly based on a given number of points in space for the formation of an electric field. The performance and visual implications of these methods were analyzed. The proposed methodology will be useful to the developer community as an embedded solution for point visualization of the electric field in any project in any algorithmic language with the ability to animate in time.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Acoustic and atmospheric gravity waves (AAGW) are generated by many natural and anthropogenic sources. The AAGW propagation at ionospheric heights is accompanied by the generation of disturbances in the magnetic and electric fields. The plasma presence plays a crucial role. The mechanisms for generating electrical and magnetic disturbances in the near-Earth atmosphere by the AAGW have been studied much worse. Therefore, the validation of the capability to generate electromagnetic disturbances in the near-Earth atmosphere by the AAGW is an urgent problem. The purpose of this paper is to describe the mechanism for generating disturbances in the electric and magnetic fields in the near-Earth atmosphere under the action of AAGW and to estimate the amplitudes of these disturbances for various AAGW sources. Design/methodology/approach: The impact of a series of highenergy sources often results in the generation of synchronous disturbances in the acoustic and geoelectric (atmospheric) fields, when an approximate proportionality between the pressure amplitude and the amplitude of the disturbances in the atmospheric electric field is observed to occur. Based on the observational data and making use of the Maxwell equations, the theoretical estimates of the disturbances in the electric and magnetic fields have been obtained. Findings: Simplified expressions have been obtained for estimating the amplitudes of the electric and magnetic fields under the action of the AAGW generated by natural and manmade sources. The amplitudes of the electric and magnetic fields generated by the AAGW of natural and manmade origin, which travel in the near-Earth atmosphere, have been calculated. The amplitudes of the AAGW generated electric and magnetic fields are shown to be large enough to be detected with the existing electrometers and fluxmeter magnetometers. The magnitudes of the amplitudes of the electric and magnetic fields generated in the near-Earth atmosphere under the action of AAGW are large enough to trigger coupling between the subsystems in the Earth–atmosphere–ionosphere–magnetosphere system. Conclusions: The estimates and not numerous observations are in good agreement.

The authors consider the aspects of the electric field distribution in an anisotropic medium and establish how its longitudinal and transverse components depend on the geometric factors. A rectangular plate of dimensions a×b×c is studied, its selected crystallographic axes located in the plane of the side face (a×b), while one of the axes is oriented at a certain angle α to the edge a. It is shown that applying a certain potential difference to the upper and lower faces electrically polarizes the volume of the plate and causes the appearance of the longitudinal and transverse components of the internal electric field. The authors investigate the possibility of transforming the magnitude of the electric field and methods for its optimization. The transformation coefficient of such a device is determined by the anisotropy of the dielectric permeability of the plate material and its shape coefficient k = a/b. The paper considers one of the design options for an anisotropic dielectric transformer and proposes its equivalent electrical circuit. Structural elements based on anisotropic dielectric transformers may be widely used both in power supplies of various electronic devices and for coordination of radar transceiver systems with antenna arrays of centimeter, millimeter and submillimeter wavelength ranges. The possibility of simultaneous transformation of constant and alternating electric fields allows them to be used in devices of simultaneous comparison, enabling to determine the current values of voltage, as well as the power of electromagnetic radiation in a wide range of wavelengths. The vortex nature of the electric field in the plate’s volume caused by the coefficient anisotropy of the dielectric permeability also creates the preconditions for the emergence of new principles for generating high-power electromagnetic radiation in a wide spectral range. The generation frequency of such devices is determined by the geometric dimensions of the anisotropic plate. The use of the described transformation effect will significantly expand the possibilities of practical application of the considered electrostatic phenomena, which will lead to the emergence of a new generation of devices for microwave technology, electronics and electric power.

The article describes a mathematical model of self-oscillation in the form of a boundary value problem for a nonlinear system of partial differential equations, with a numerical solution. The numerical results were compared to the experimental data to confirm the adequacy of the model. The model uses the classical system of differential equations of material balance, Nernst-Planck and Poisson equations without simplifications or fitting parameters. The aim of the article was to study the parameters of concentration self-oscillation in a layer of the dispersed phase particles of magnetic fluid at the interface with an electrode in an electric field. For this purpose, we developed a mathematical model, the consistency of which was confirmed by the corresponding physical mechanism. As a result of numerical experiments, we found the critical value of the potential jump after which self-oscillation began. We also determined the oscillation growth period and other characteristics of the process. We developed software called AutoWave01 with an intuitive user interface and advanced functionality for the study of self-oscillation in a thin layer of magnetic colloid.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. Intensification of competition and the desire to reduce the cost of high-voltage electric machines due to a significant increase in the electrical and thermal loads of the electrical insulation system complicate the operation of anti-corona coatings on the insulation surface of the stator winding and increase the intensity of discharge processes, which significantly reduce the life of the insulation in case of failure of the coatings. Purpose. The analysis of the efficiency of alignment of the electric field along the insulation surface of the stator winding of high-voltage electric machines with semiconductor anti-corona coatings. Methodology. A method for calculating the electric potential distribution along the surface of the winding insulation during the use of semiconductive coatings providing alignment decrease the electric field and eliminating the appearance of moving discharges. The reliability of the calculations is confirmed by experimental studies of the potential distribution over the surface of the anti-corona semiconducting non-linear coating along the frontal part of the samples of the rod of the hydrogenerator for a linear voltage of 20 kV. Practical value. The proposed methodology for calculating the distribution of the electric field over the surface of the insulation and the anti-corona semiconductive coating can be applied to justify the length of the coating in the frontal part of high-voltage electrical machines depending on the electrophysical characteristics of the coating, electrical insulation, and thickness. The results of an experimental verification of the stability of the nonlinear properties of coatings during prolonged electrical and thermal aging of specially made coating samples are presented.

Desorption of cesium atoms in an electric field from the carbonized rhenium field emitter was investigated by the field desorption microscopy. The effect of the concentration of cesium atoms on the voltage and on the distribution of emission centers on the surface of the emitter is studied. It is shown that rhenium carburization can lead to a surface modification with the formation of carbon nanostructures.

Purpose. The complex approach to calculating thunderstorm overvoltage on substation equipment is considered when lightning strikes in a lightning rod. Methodology. The conditions of safe passage of lightning current through a lightning arrester are formulated. Results. It is shown that the calculation of the permissible length of air insulating gaps in the substation is based on the breakdown of the air tension, which is assumed to be 500 kV/m. This leads to an error in calculating the length of the air gap and, as a consequence, the probability of its breakdown, the value of which is used to calculate the indicator of the lightning resistance of the substation. A technique is proposed for calculating the permissible voltage on the transformer case when a lightning strike strikes the lightning receptacle of the transformer portal. On the basis of the nonlinear pulsed electric strength of the ground, the specified minimum permissible ground distance between the grounding rod of the lightning rod and the nearest point of the protected device is obtained. Originality. Refined calculation of the length of the minimum breakdown gap in the air and in the ground. Practical value. The proposed approach makes it possible to calculate thunderstorm overvoltage on substation equipment.

The relevance of the research is caused by discrepancies in design of cathodic protection of pipelines. Electric current, flowing from anodic protection to the ground, spreads there and then enters the protected pipeline polarizing its cathode. Certain assumptions are taken to describe the patterns of change imposed by the potential and strength of the polarizing current along the length of the pipeline at a cathodic protection. There are significant differences between design and actual parameters of protection in settlements of cathodic protection of pipelines. The main aim of the research is to propose an algorithm for solving a boundary value problem for the potential of the electric field of cathodic protection of an underground pipeline by a vertical depth anode based on the method of fictitious sources. Objects: gas and oil pipelines, for which protection against electrochemical corrosion is a necessary condition for ensuring an optimum period of their operation. Methods. Based on the method of fictitious sources the authors have proposed the algorithm for solving the boundary-value problem for capacity of the electric field of cathodic protection of underground pipeline vertical deep anode. Application of the method is justified by the principle of electrostatic analogy for spatial task of electric field distribution. Results. To apply the established relation to this problem in half, the method of mirror reflections is used additionally in the algorithm that allows transferring the task from half to space. The C++ computing code is developed for numerical calculations of electric fields in the systems of cathodic protection of pipelines via deep anodes subject to the restrictions on the electric potential of the protected structure and the density of current, flowing from the anode. The computer model allows conducting a set of numerical experiments for selection of geometric and electrochemical parameters of designed deep anode, to improve the reliability of cathodic protection for underground structures and increase the duration of their service life. The paper introduces the graphs illustrating the features of current density distributions along the depth of anode and the protective capacity of the pipeline, with changes in the external environment for a certain period of operation. It was shown that at decrease in insulation resistance the increase in cathodic station current is required for maintaining the necessary protective pipeline capacity. Current density at the «anode–ground» boundary increases that leads in its turn to more intensive anode dissolution. The paper introduces the examples of numerical results obtained based on real data conditions. The analysis of the results confirms the effectiveness, stability and versatility of the algorithm developed.

It is known that in wet steam turbines the wet steam flow is electrified when passing through the turbine flow path. In this, the mutual electrification of the condensed moisture flow and flow path surfaces occurs. Until now, experts in the field of steam turbine operation have been aware of the problem of electrical phenomena in flow paths in terms of electroerosion phenomena associated with the accumulation of electric charges on the rotors. Similar phenomena in the working fluid flow are less known. As a result of the research conducted at IPMash NAS of Ukraine, it has been established that the electrification of the wet steam flow leads to the formation of a volume charge in the flow path, which can have a significant value (up to 10–3 C/m3) and exert a significant effect on the working processes in the turbine and condenser. The volume charge of the steam flow in the flow path also generates electric fields with constant and variable components. As a result, parts and assemblies of the flow path may be under the action of an electric field. In particular, turbine blades may be in the electric field of the volume charge of the working fluid. As is known, the impact of an electric field can reduce the strength of the metal surface layer. Therefore, an experimental study of the effect of electric fields, similar to those occurring in the turbine flow path, on the strength properties of blade steel is an important task. The article presents the results of the experimental determination of the microhardness of the 15H11MF blade steel surface layer exposed to a constant or variable electric field. It is shown that its effect significantly reduces the microhardness of the blade steel surface layer. Since the strength of the surface layers of the working blades is one of the most important characteristics of their erosion resistance, the effect of the electric field of the steam flow volume charge can be one of the negative factors that reduce the erosion resistance of turbine blade surfaces. Based on the obtained results, it can be concluded that it is necessary to further improve the system for neutralizing the accumulation of electric charges in the flow path, which currently mainly performs the function of turbine rotor grounding.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A brief review of articles developing the quantum tunneling with dissipation theory, as well as its applications to various problems in condensed matter physics, in particular, quantum mesoscopy of nanostructures, has been presented. A generalization of the instanton method to the case of impurity quasistationary states in quantum molecules described in the model of a double-well oscillatory potential has been also considered. The flexibility of the instanton method is demonstrated, which allows, in combination with the physics of low-dimensional systems, to obtain the solution of problems on the optical and transport properties of quantum molecules with impurity quasistationary states in an analytical form, as well as to take into account the effect of external fields. Part I of the article is presented in № 1 for 2017.

Field desorption microscopy was used to study the surface of the rhenium field emitter after its carbonization. Field electron and field desorption images of the surface after carbonation at adsorption of sodium atoms are obtained. On the basis on the analysis of modifications of the field electron and field desorption images of the surface at different values of the electric field we concluded that formation on the surface of the carbonized rhenium of bulk graphite nanostructures affects the emission processes.

The diffusion of cesium over the rhenium surface and the rhenium surface coated with carbon was studied by methods of the field electron and desorption microscopy. The method of continuous field desorption was used, in which surface diffusion ensures the flow of the adsorbate to the desorption site. It was found that the carbon-coated surface undergoes intensive diffusion of cesium, while there is no diffusion on the rhenium surface.

Examination of the degree of non-uniformity of the electromagnetic field assumes the estimate necessary for determining the type of the field and further standard classification, for the purpose of establishing dependencies and determining the applicability of existing and developed sensors in research of parameters of electromagnetic fields. The task of the study is to provide a methodology for determining field non-uniformity, since this problem has not been solved in the prior art. Classification and quantitative evaluation of degree of non-uniformity will allow to detect informative parameters necessary in designing new sensors of electromagnetic fields.

In the present paper, the analysis of structures of modern photoelectric solar energy converters is carried out. The solution of ecological problems at increasing energy consumption and limitations of traditional earthly resources makes the tasks of using alternative and renewable energy sources actual. The sun is a practically unlimited energy source for earthly applications. Development of effective structures and designs of photoelectric converters provides the access to this source. Currently, their practical application is limited due to the high cost of solar batteries. The paper generalizes the known results of solving the problems of creating photoelectric converters. The design and operation principles of photoelectric converters are shown, single- and 3-stage elements are considered. Conditions for efficient operation of photoelectric converters are determined. Particular attention is paid to materials for creating elements of photoelectric converters. The paper considers the peculiarities of materials in which potential barriers are formed and pairs of electrons and holes are generated. In addition, the paper deals with the materials that are used for forming the constructions of photoelectric converters, namely, the materials of plates, contacts etc. These materials must provide a considerable barrier height in a semiconductor junction. The generated electrons and holes are effectively collected at contact electrodes. The considered conditions of efficient operation of photoelectric converters determine their practical importance. It is shown that the further increase of efficiency of photoelectric converters requires the development of technologies, improvement of structures, and application of physical principles that are not used yet, as well as new combinations of those that are already being used.

The article presents the results of a long-term research performed by national and international scientists in field of intensification of the process of sucrose extraction from sugar beet cossettes. The data characterizing the efficiency of electrical treatment on the structure of sugar beet tissue and changes in its physical properties are presented. The quality indicators of diffusion and purified juices obtained by classical and experimental technologies are given. The prospects of introduction of technologies for the processing of sugar beet cossettes by electric and electromagnetic fields in the sugar beet industry are estimated.

The spectral parameters ultrafine particles Zn2SiO4-Mn, precipitated on the substrate in a magnetic or electric field have been investigated. For getting fine particles industrial phosphor K-60 (Zn2SiO4-Mn) was used. Luminescence spectra were obtained on a sample when exposed to ultraviolet light or a beam of charged oxygen ions. When excited by ultraviolet spectral characteristics have difference for samples with different dimensions of the crystals. As for the industrial design luminescence spectrum had a band with λmaх = 521 nm, and for the ultrafine crystals willemite spectral band had λmax = 550 nm. Analysis ionoluminescence spectra showed that the reduction of crystal size Zn2SiO4-Mn not affect the spectral characteristics of the excitation beam with low energy oxygen ions. The luminescence spectrum when exposed to low-energy ions (1-3 KeV) has a band with λmax = 521 nm and a half-width Δλ = 41 nm. When measuring the width of the forbidden zone has been established bandgap dependence on the size of the phosphor crystals. The width of the band gap increases with decreasing crystal size to nanoscale sizes. A significant effect was obtained when deposited on a substrate in the nanoscale crystal magnetic or electric field. As for the industrial design the bandgap was 4.16 eV, and for the besieged in the magnetic and electric field of 4.27, 4.29 eV, respectively.

Statistical estimates of the effect in the electric field of the surface layer of the atmosphere parameters, such as time of the beginning, time of a maximum, its intensity and duration, were obtained. It was shown experimentally that the diurnal variation maximum of atmospheric electric field intensity is associated with air temperature height distribution. Power spectra of time variations of electric field intensity in the near ground atmosphere and of the horizontal component of geomagnetic field were under study. It was shown that there are oscillations with the periods of T _ 2, 0–2,5 hours in the power spectra of these parameters during a day. A possible mechanism of generation of these oscillations was proposed. It is associated with vortex motion of convective cells arising during the sunrise in the atmosphere exchange layer.

The relevance of the research is related to searching the efficient ways of deposition of fine aerosols to clean production rooms from dust and smoke. Development of methods of ensuring purity of air environment in production rooms are especially relevant in connection with the development of nanotechnologies as well as engineering chemistries, related to possible emissions of harmful and dangerous dust. The main aim of the research is searching for optimum ways of deposition of fine aerosols comparing electrostatic and ultrasonic deposition of particles. Objects of the research are fine aerosols and ways of their deposition. Methods: mathematical modeling, optical methods of measurement of distribution function of particles by the sizes and concentration of aerosol particles using the laser measuring system LID2M and the Malvern Spraytec analyzer. Results. The authors have carried out the theoretical analysis of sedimentation rates of particles of fine aerosols (diameter of particles ~1-20 µm) in the presence of acoustic, electric field taking into account a drift in electric field, ultrasonic coagulation, and acoustic flows («sound wind»). The key mechanisms of particles deposition depending on their size are defined that allows proposing the optimum ways of deposition of fine aerosols in each range of particle sizes. The mathematical model of acoustic coagulation is based on an integral form of the equation of Smolukhovsky. The paper introduces the results of the experimental study of the model aerosol (NaCl) particles deposition with the reference diameter of particles about 6 µm by means of ultrasound and electrodeposition device. It is defined that application of these ways of deposition is essential (and it is approximately identical) and it accelerates considerably sedimentation of the model aerosol that corresponds to theoretical results. On the other hand, theoretical calculations predict that application of electrostatic way of deposition will be more effective in comparison with the ultrasonic one for aerosols with rather larger particles.

Atmospheric dust is a mixture of minute particles of various salts and minerals; it also contains the remains of plants and animals, spores of pathogenic microbes, etc. The winds carry the dust over long distances, and its presence in the atmosphere is one of the factors that significantly affect the planet's climate. Currently, for space monitoring of aeolian processes and their consequences only multispectral optical systems are used (TOMS, METEOSAT, MODIS, etc.); they cannot identify the areas which are the sources of raising dust in the atmosphere regardless of clouds, brightness and transparency of the atmosphere. This problem can be solved by the space remote sensing radar systems. The article presents the first results of processing the method of radar identification of desert areas in which under the influence of aeolian processes the process of raising dust from the surface to the atmosphere takes place. The testing was performed using the data of radar remote sensing of Mauritania deserts of SAR Envisat-1. The peculiarities of manifestation of focused backscattering of radio waves in radar images at different speeds of surface wind, surface radar radiation and wind directions were analyzed. It is concluded that applying the radar remote sensing to identify areas raising dust in the atmosphere is effective. The results of the study allow to create new methods of remote monitoring of processes in desert areas, affecting the climate of vast regions of the Earth.

In the article are considered the study of fundamental changes in the parameters of fluorescence (TRo/RC, ETo/RC, DIo/RC, ABS/RC, Fv/Fm и PIabs) of the photosynthetic apparatus of trees (birch, fir) in conditions of electric lighting’s fields and of electric fields like in nature but making by technology. The content of article focuses on the monitoring of stress in the different environmentsand uses analysis by JIP-test, the light curves and non-photochemical quenching, etc. The content of this article will demonstrate the possibility of the technique and will hopefully encourage the development of new uses that are not reported in other articles.

A survey of mathematical models employed in modern electrohydrodynamics of weakly conducting fluids is given. The models are described in the order of increasing complexity. Some results obtained in the framework of each model are presented. The models considered include: the model of a unipolarly charged medium consisting of a continuous carrier fluid and an admixture of charged particles of the same sign; a more sophisticated two-ion model containing two charged admixtures of opposite signs; and the model with three different kinds of ions. In the framework of the aforementioned models, it is possible to adequately interpret almost all experimental data related to electrohydrodynamic flows that can be found in the literature. Further elaboration of the model may be needed to simulate particular electrochemical processes without introducing averaged (“effective”) macroscopic parameters. Four basic phenomena of fluid electrization (generation of an uncompensated electric space charge in the fluid) are described and analyzed.

The paper studies the evolution of values for the characteristic electric field and magnetic field generated by power line voltages and currents voltage 110 kV their value based snapshots. These evolutions we examined in changing the value of the angle of the voltage vector and current vector within 0o...180o. The conductors are placed horizontally and triangle tops with different lengths of the sides. The electric field distribution was calculated with finite volume method. Since the electric field distributions were determined parameter values of LEA110 kV. The values of the line parameters, which were determined by the finite volume method, difference from the values calculated by the traditional method. In this context finite volume method presents attractive enough to determine the parameters of power lines and spatial distribution of the electric field in three-phase lines.

This paper describes a device for studying the spatial distribution of ions formed at high-speed collision of solids. A variant of the construction and structural scheme of the device, which increases the accuracy of the information about the physical parameters of a rigid body strikes. The device provides the ability to study the distribution of ions formed in space at different angles of the collision solids. Consider the motion of ions in the electrode system at different angles to the electric field inhibitory.

The paper examines an approach to finite volume method which is used to calculate the electric field in three-dimensional environment. It is formulated the problem Dirichlet with building of the computational grid on base of space partition, which is known as Delaunay triangulation with the use of Voronoi cells. It is proposed numerical algorithm for calculating the potential, electric field strength and capacitance in the 3-d sphere with cubic cavity. There are presented results of calculations of distribution in the potential space, electric field strength, and capacitance of the 3-d sphere with cubic cavity.

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Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper examines a new approach to finite volume method which is used to calculate the electric field of spatially inhomogeneous three-dimensional environment. The Dirichlet problem is formulated and the computational grid is constructed on the base of space partition, which is known as Delaunay triangulation with the use of Voronoi cells. To calculate the potential and the electric field strength in the vicinity of the electric line support the numerical algorithm is proposed. We have developed the algorithm and the corresponding software using Matlab application. There are presented some numerical results of calculations of the distribution of potential and of the electric field strength.