Electromagnetic Field Parameters Research Articles

Determining triple half-twist of optical Möbius strips in electromagnetic fields with a non-planar structure.

Polarization ellipses in a nonparaxial field form twisted strips when traced along closed contours around a circular polarization singularity line. We found an analytical expression for the twist number of the strip when the contour is coplanar with the polarization ellipse in its center. Necessary and sufficient conditions for strips having one or three half-twists are found. A set of five parameters of electromagnetic field at the polarization singularity point is found which definitely determines the value of the twist number of the strip.

SPECIFICS OF THE COMBINED ELECTROMAGNETIC AND THERMAL PRE-TREATMENT OF THE COAL-WATER FUEL

An increase in fuel usage efficiency is the path to eliminate environmental impact, decrease greenhouse gas emissions, and prevent climate warming. Coal-water fuel (CWF) is seen as a replacement for coal and heavy oil in some applications but it has a number of disadvantages that must be addressed before it can be gasified or burned. Pretreatment (or activation) is one of the methods for improving the fuels. Since CWF is an electrically conductive substance, the electromagnetic field can be used for various types of influences: heating, stirring by rotation, etc. Numerical research was carried out to study the possibility of simultaneous heating and movement of CWF by a rotating electromagnetic field created in the stator of an asynchronous electric motor. The correlations between the required electromagnetic field parameters and tangential velocity profile were investigated. It was found that a change in the position of the maximum tangential velocity with increasing rotation speed can lead to a decrease in magnetic reluctance and, consequently, to a decrease in the active power required to rotate the CWF.

Assessing the parameters of electromagnetic fields and microclimate in the radionuclide department of the positron emission tomography centre

Currently, in the Russian Federation there is an increase in the number of positron emission tomography scans. As a result, the collective dose from radionuclide diagnostics in 2021 compared to 2020 increased by 62.0%, the average effective dose per one study in positron emission tomography (PET) centres of Moscow from 2015 to 2019. increased from 1.71 to 4.41 mSv. This leads to an increase in radiation doses not only for patients, but also for medical workers, and makes it urgent to develop modern effective measures to prevent the adverse effects of ionizing radiation.
 The aim of the study is to evaluate the parameters of electromagnetic fields and microclimate in the premises of the radionuclide department of the PET centre.
 During the study, in the main working areas of the radionuclide department, the following levels were assessed: the strength levels of electric and magnetic fields of industrial frequency, relative humidity, temperature and air speed using generally accepted measures in occupational hygiene.
 zThe main parameters of electromagnetic fields and microclimate (temperature, humidity, air speed) comply with hygienic standards in industrial workplaces. At the same time, in certain working areas of the radionuclide department, higher levels of electromagnetic fields were recorded, as well as a decrease in relative humidity and air velocity.
 Monitoring the parameters of electromagnetic fields and microclimate is important for improving the working conditions of medical workers in the radionuclide department of the PET centre, which helps maintain the functional state of workers at a high level, increases concentration and accuracy of movements, increases the speed of work manipulations, and reduces the time of contact with radionuclides when administered to patients and thereby reduce the dose load on health workers.
 Ethics. The study does not require the opinion of this committee.

Grain Seed Treatment by a Low-Frequency Electromagnetic Field

The paper notes the potential for enhancing seed productivity through exposure to an electromagnetic field. It touches upon both theoretical and practical considerations for developing an experimental laboratory plant for pre-sowing seed treatment using a low-frequency electromagnetic field and aiming to achieve a magnetobiological effect. (Research purpose) The study aims to investigate the influence of low-frequency electromagnetic field on the composition and properties of grain seeds. (Materials and methods) Standard emitters, characterized by a magnetic induction variability of 3-75 millitesla and a radiation frequency of 1-100 Hertz, were employed to ensure the necessary treatment parameters for a batch of seeds. (Results and discussion) The study investigates the impact of magnetization on the germination process, germination energy, and the physical and chemical properties of seeds subjected to different parameters of a low-frequency electromagnetic field (ranging from 3 to 75 millitesla in magnetic induction and a radiation frequency of 10-16 Hertz).The quality of the effect was analyzed with respect to the installation parameters and seed mass, ranging from 10 to 500 grams, across various cereal crops. Subsequently, specific modes were identified, and a functional irradiation program was devised to ensure a highly effective impact on seeds, optimizing their germination, sprouting and development. (Conclusions) The impact of a low-frequency electromagnetic field on the composition and properties of grain has been studied. An experimental laboratory plant with sources of a low-frequency electromagnetic field has been developed and irradiation modes have been justified. The pre-sowing treatment of an industrial batch, the magnetobiological effect is contingent upon several factors, including the crop type and variety, activation of a biological complex in a cell that initiates the development of a seedling, seed quality and moisture content, the presence of microorganisms on the surface, pathogenic ones included, and the characteristics of irradiation sources and energy parameters. The parameters of the low-frequency electromagnetic field were determined as follows: magnetic induction ranging from 3 to 75 millitesla, a frequency 10-16 Hertz, and seed weight varying from 10 to 500 grams. These identified parameters will be applied in the development of an industrial unit designed for the preparation of seed material and enhancement of its sowing properties.

Variations in cosmic ray cutoff rigidities during the March 8–11, 2012 magnetic storm (CAWSES II period)

The geomagnetic cutoff rigidity of cosmic rays (CRs) is the main factor regulating the arrival of CR particles at a given point on Earth's surface or inside the magnetosphere. To study the relationship between cutoffs and near-Earth space parameters, we have selected the strongest magnetic storm that occurred on March 8–11, 2012 during the CAWSES-II interval, recommended by SCOSTEP for detailed studies of solar-terrestrial relations. We have found the geomagnetic cutoffs by two methods: 1) by trajectory calculations in the magnetic field of the perturbed magnetosphere according to the Ts01 model and 2) by the spectrographic global survey method according to the data from the world network of neutron monitors. The largest drop in the cutoffs (−1.1 GV) obtained by the latter method was observed during the recovery phase of the storm. Apparently, this is due to the influence of the supersubstorms that occurred at that time. The analysis has shown that the closest connection of variations in the cutoffs can be traced with the geomagnetic activity index Dst, which indicates the determining contribution of the ring current to the transport of CRs. In addition, we have found a significant connection with the electromagnetic field parameters (with the Bz component of the interplanetary magnetic field and the azimuthal component of the electric field Ey). The dynamic solar wind parameters practically do not control variations in CR geomagnetic cutoff rigidities.

Изменения жесткостей обрезания космических лучей во время бури 8–11 марта 2012 г в период CAWSES-II

The geomagnetic cutoff rigidity of cosmic rays (CRs) is the main factor regulating the arrival of CR particles at a given point on Earth's surface or inside the magnetosphere. To study the relationship between cutoffs and near-Earth space parameters, we have selected the strongest magnetic storm that occurred on March 8–11, 2012 during the CAWSES-II interval, recommended by SCOSTEP for detailed studies of solar-terrestrial relations. We have found the geomagnetic cutoffs by two methods: 1) by trajectory calculations in the magnetic field of the perturbed magnetosphere according to the Ts01 model and 2) by the spectrographic global survey method according to the data from the world network of neutron monitors. The largest drop in the cutoffs (−1.1 GV) obtained by the latter method was observed during the recovery phase of the storm. Apparently, this is due to the influence of the supersubstorms that occurred at that time. The analysis has shown that the closest connection of variations in the cutoffs can be traced with the geomagnetic activity index Dst, which indicates the determining contribution of the ring current to the transport of CRs. In addition, we have found a significant connection with the electromagnetic field parameters (with the Bz component of the interplanetary magnetic field and the azimuthal component of the electric field Ey). The dynamic solar wind parameters practically do not control variations in CR geomagnetic cutoff rigidities.

Modeling of the Temperature Regimes in a Layered Bimetallic Plate under Short-Term Induction Heating

A mathematical model for determining the temperature field of a bimetallic plate with plane-parallel boundaries during short-term induction heating by a non-stationary electromagnetic field is proposed. Initial boundary value problems for determining the parameters of a non-stationary electromagnetic field and temperature are formulated. The temperature and the component of the magnetic field intensity vector that is tangential to the plate base were selected as defining functions. We used an approximation of the defining functions in each layer of the plate with quadratic polynomials by the thickness coordinate and Laplace transform of the integral over time. General solutions to the formulated problems under uniform non-stationary electromagnetic action were obtained. Based on them, the temperature during short-term induction heating by a non-stationary electromagnetic field was numerically analyzed depending on its amplitude-frequency parameters and duration.

Fabrication of Electromagnetic Damper

Abstract: This research study investigates the development of an electromagnetic suspension system for application in highspeed transportation. Using magnetic fields, the technology is intended to elevate and stabilize a vehicle. The construction process and materials utilized to create the suspension system are described in the publication. Testing and evaluating the system's performance, such as its capacity to retain stability and levitation under varying speeds and loads, are part of the research. The research also investigates the effects of changing electromagnetic field parameters on system performance. The study's findings indicate that electromagnetic suspension systems are a promising technology for high-speed transportation, with applications in maglev trains and other comparable vehicles

Phagocytosis of latex beads by a human monocytic Mono Mac 6 cell line and effects of low-frequency electromagnetic field interaction.

Some studies have shown that electromagnetic fields (EMFs) may impact immune response cells and their functions. The first stage of the defense from pathogens is innate immunity encompassing phagocytosis and phagocytosis-related intracellular effects. Our work aimed to determine the influence of a low-frequency electromagnetic field (7 Hz, 30 mTrms) on the phagocytosis process of latex beads (LBs), the production of reactive oxygen species (ROS), and viability changes in a human monocytic Mono Mac 6 (MM6) cell line as an experimental model of the phagocytosing cells in in vitro cell culture conditions. For these purposes, cells were firstly activated with infectious agents such as lipopolysaccharide (LPS), Staphylococcal enterotoxin B (SEB), or the proliferatory agent phytohaemagglutinin (PHA), and then a phagocytosis test was performed. Cell viability and range of phagocytosis of latex beads by MM6 cells were measured by flow cytometry, and the level of ROS was evaluated with the use of a cytochrome C reduction test. The obtained results revealed that applied EMF exposure mainly increased the necrosis parameter of cell death when they were pre-stimulated with SEB as an infectious factor and subsequently phagocytosed LBs (P=0.001). Prestimulation with other agents like LPS or PHA preceding phagocytosis resulted in no statistically significant changes in cell death parameters. The level of ROS depended on the used stimulatory agent, phagocytosis, and/or EMF exposure. The obtained effects for EMF exposure indicated only a slight decrease in the ROS level for cells phagocytosing latex beads and being treated with SEB or PHA, while the opposite effect was observed for LPS pre-stimulated cells (data not statistically significant). The results concerning the viability of phagocytosing cells, the effectiveness of the phagocytosis process, and the level of radical forms might result from applied EMF parameters like signal waveform, frequency, flux density, and especially single EMF exposure.

Forming an elliptical directional diagram of the sectoral horn antenna for flow irradiation of sugar beet seeds by electromagnetic field

The object of research is the process that forms an elliptical directional diagram of the H-sector horn antenna for flow irradiation of seeds with the electromagnetic field. The emitter of electromagnetic energy is presented as one of the main elements of installations for irradiating seeds with an electromagnetic field before sowing. This parameter was investigated by taking into account the values of the biotropic parameters of the low-energy electromagnetic field under the conditions of flow processing. This paper reports a study into the parameters of the H-sector horn emitter for irradiation of sugar beet seeds with a low-energy electromagnetic field at a frequency of 73...75 GHz in continuous flow. Thus, one should use the H-sectoral horn emitter with the following parameters: aperture width aa=20 mm; horn length RH=35 mm; b=1.8 mm. It is determined that in order to irradiate sugar beet seeds on the conveyor plane with a power flow density of P=100 μW/cm2, it is necessary to place two horns 1200 mm above the conveyor at a distance of 2540 mm from each other. It was checked that the treatment of sugar beet seeds with electromagnetic radiation in a continuous flow with a capacity of 300 kg/h is possible with a power of up to 2 W supplied to two horn antennas; the speed of the conveyor is 15 cm/s. The parameters of the sectoral horn for an elliptical directional diagram were studied by dividing the main task into internal and external. According to the results of the research, it is possible to build a base of geometric presets for adjusting installations for different types of seeds, the desired performance, the structural features of installations, as well as existing emitters

Study on Processing Grinding Sludge Conglomerates in Devices with a Rotating Electromagnetic Field

Introduction. The key stages of sludge processing technology are the destruction of conglomerates into metal and non-metal components, as well as the grinding of component particles to obtain secondary raw materials of the required granulometric composition. The use of a rotating electromagnetic field for processing grinding sludge makes it possibleto exclude the application of various means of destruction and grinding, avoiding contact interaction of agglomerates and the walls of the working chamber. Thus, the material consumption of technical means is reduced, and the efficiency of the destruction process is increased. The study aimed at establishing the features and basic patterns of sludge waste processing in devices with a rotating electromagnetic field. Materials and Methods. For the research, grinding sludge was used, which was a collection of conglomerates of arbitrary shape, consisting of 80-85 % of metal chips. An induction method was applied based on establishing the connection of the EMF induced in an induction sensor and the magnetic induction of a rotating electromagnetic field. The influence of induction on the nature of interaction between sludge particles in a rotating electromagnetic field was evaluated by changing the relative EMF signal induced in an inductive sensor. Results. As a result of experimental studies conducted using the induction method, it has been found that the dynamic characteristics of sludge waste conglomerates depend on the induction of a rotating field to a certain value. With an increase in the size of sludge conglomerates, with the same size of ferromagnetic particles entering it, the magnitude of the magnetic field induction required for their destruction decreased. With a decrease in the particle size of conglomerates, the field induction required for the destruction of conglomerate bonds increased. An increase in the number of particles in the conglomerate reduced the value of induction. The degree of destruction of the conglomerate and the grinding of its ferromagnetic particles depended on the duration of the rotating electromagnetic field induction. Discussion and Conclusions. The proposed induction method makes it possible to investigate the influence of electromagnetic field parameters on the change in the state of the magnetic vibrating layer, as well as to evaluate the kinematic characteristics of ferromagnetic medium particles in the magnetic vibrating layer.

Diagnostic method for the selection of regimes of electromagnetic effect on the particulate ferromagnetic material

The recycling of obsolete permanent magnets, the processing and reusing of the obtained powder for a new magnets production has both economic and environmental benefits. The processing of recycled magnetic slur to the particle size distribution required for the magnets production has a problem specific for fine magnetic powders – particle aggregation limiting the milling efficiency. One way of solving this problem is milling the magnetic material with the formation of the magneto fluidized bed. In the present work we study the behavior of the recycled from old electromotor stators strontium hexaferrite powders with average particle sizes 56.8 µm and 7.5 µm in the magneto fluidized bed formed by mutually perpendicular constant and alternating gradient magnetic fields. The desired state of the fluidized bed for milling is the one with the maximal particle motion intensity that prevents particle aggregation. The intensification of particle motion could be done by the increase of the alternating magnetic field gradient, but this also increases energy consumption of the process. In the present paper we propose using the inductive method for estimating rheological state of the strontium hexaferrite powder in the magneto fluidized bed. Such estimation allows finding the optimal parameters of electromagnetic fields forming the fluidized bed for the efficient powder milling process.

FDTD Simulations of Shell Scattering in Au@SiO2 Core-Shell Nanorods with SERS Activity for Sensory Purposes.

The article describes the results of Finite-Difference Time-Domain (FDTD) mathematical modeling of electromagnetic field parameters near the surfaces of core-shell gold-based nanorods in the Au@SiO2 system. Three excitation linewidths (λ = 532, 632.8, and 785 nm) were used for theoretical experiments. Electric field parameters for Au nanorods, Au@SiO2 nanorods, and hollow SiO2 shells have been calculated and evaluated. The correlations between electric field calculated parameters with nanorod morphology and shell size parameters have been clarified. The optical properties of nanoobjects have been simulated and discussed. The highest maximum calculated value of the electric field tension was E = 7.34 V/m. The enhancement coefficient was |E/E0|4 = 3.15 × 107 and was obtained on a rod with a SiO2 shell with dimensional parameters of height 70 nm, rod width 20 nm, and shell thickness 20 nm. As a result, a flexible simulation algorithm has been developed for the simulation of electric field parameters in each component of the Au@SiO2 system. The developed simulation algorithm will be applicable in the future for any other calculations of optical parameters in any similar component of the core-shell system.

Nanotherapy based on magneto-mechanochemical modulation of tumor redox state.

Magnetic nanoparticles (MNs) are typically used as contrast agents for magnetic resonance imaging or as drug carriers with a remotely controlled delivery to the tumor. However, they can also potentiate the action of anticancer drugs under the influence of applied constant magnetic (CMFs) and electromagnetic fields (EMFs). This review demonstrates the role of magneto-mechanochemical effects produced by MNs alone and loaded with anticancer agents (MNCs) in response to CMFs and EMFs for modulation of tumor redox state. The combined treatment is suggested to act by two mechanisms: spin-dependent electron transport propagates free radical chain reactions, while magnetomechanical interactions cause conformational changes in drug molecules loaded onto MNs and generate reactive oxygen species (ROS). By adjusting the parameters of CMFs and EMFs during the magneto-mechanochemical synthesis and subsequent treatment, it is possible to modulate ROS production and switch redox signaling involved in ERK1/2 and NF-κB pathways from initiation of tumor growth to inhibition. Observations of tumor volume in different animal models and treatment combinations reported a 6%-70% reduction as compared with conventional drugs. Despite these results, there is a general lack of research in magnetic nanotheranostics that link redox changes across multiple levels of organization in the tumor-bearing host. Further multidisciplinary studies with more focus on the relationship between the electron transport processes in biomolecules and their effects on the tumor-host interaction should accelerate the clinical translation of magnetic nanotheranostics. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Methodological approaches to measuring and evaluating the effects of electromagnetic fields generated by smartphones

Introduction. Among the population, smartphones are the most common mobile radio frequency receiving and transmitting devices with a complex operating system, a microprocessor, a large amount of memory, etc. It is an urgent task to measure and evaluate the smartphone electromagnetic fields (EMF) exposing to a person. The purpose of the study. Comparative analysis of domestic and foreign methodological approaches to measuring and evaluating electromagnetic fields of the radio frequency range (RF) created by smartphones. Materials and methods. Analysis of foreign and domestic regulatory and methodological documents, scientific publications on the measurement and evaluation of the effects of EMF of mobile phones. Conducting pilot instrumental measurements during the operation of smartphones in the real mode of using the subscriber terminal. Results. There are presented results of the study of electromagnetic radiation (EMR) of smartphones. The study of methodological approaches to measuring and evaluating the smartphone EMF in foreign and domestic regulatory and methodological documents, publications on the issue under consideration in scientific peer-reviewed journals. There have been performed pilot instrumental measurements of energy flux density (EFD) levels of EMF when different smartphone models are working indoors in dial mode. Limitations. The measurement of EMF levels by the broadband measuring instrument PZ-42 limited the possibilities of a detailed assessment of EMF. Conclusion. A detailed study of the EMF parameters created by smartphones in a wide range of frequencies and under various operating modes (data reception/transmission using the Internet, Wi-Fi connections, operation in router mode, etc.) is required. It is necessary to develop and manufacture domestic selective devices - EMF meters of the radio frequency range, including in the near zone radiation.

Determination and Analysis of Joule’s Heat and Temperature in an Electrically Conductive Plate Element Subject to Short-Term Induction Heating by a Non-Stationary Electromagnetic Field

We propose a mathematical model that allows us to determine the temperature field of a parallel-sided electrically conductive plate element subject to uniform non-stationary electromagnetic action. We formulate initial-boundary value problems to determine the parameters of the non-stationary electromagnetic field (NEMF) and the temperature. We develop a methodology to solve these initial-boundary value problems using the approximation of determining functions by cubic polynomials over thickness of the plate element. General solutions for the related Cauchy problems at uniform non-stationary electromagnetic action are obtained. Based on these solutions, the temporal variation of Joule’s heat and temperature in the plate element, subject to short-term induction heating by an NEMF in the mode of impulse modulating signal (MIMS), is analyzed. Temperature dependencies on the different values of electromagnetic field stress and on the different time duration were obtained. The choice of the carrier frequency of electromagnetic field oscillations is explained for the frequencies mostly used in industrial devices for inductive heating.

Features of high-density transient electromagnetic sounding data inversion under oil and gas prospecting in the Nepa-Botuoba anteclise area

The data of near-field transient electromagnetic sounding, which are widely used for the purposes of oil and gas exploration within the Nepa-Botuoba anteclise, are typically interpreted in terms of quasi-horizontally-layered models of media. The purpose of this study is to develop an approach to the inversion of transient electromagnetic sounding curves obtained via high-density 3D observation networks. The study was based on mathematical modeling, whose results allowed to estimate the lateral spatial parameters of a non-stationary electromagnetic field as well as to understand the differences between the results of one-dimensional inversion of the transient electromagnetic sounding data and the true parameters of the target horizon. As a result, the characteristic of the electromagnetic field described by an exponential function and used in the lateral-constraint inversion of high-density electromagnetic sounding was obtained. The proposed approach was tested on the practical data within the site under investigation located on the slope of the Nepa-Botuobа anteclise. It is shown that the use of spatial discrepancy under TEM sounding data inversion makes it possible to obtain geoelectric models characterized by lateral consistency of section geoelectric parameters. The application of the spatial stacking-based approach in the inversion process allows to increase the solution stability of the inverse problem of the near-field TEM sounding data.

On the interaction between Λ-type five-level atom and one-mode squeezed coherent field

This article investigates the effect of the detuning interaction parameters of a single-mode electromagnetic field with a five-level Λ-type. The differential system is solved in the presence of detuning parameter under the initial conditions when the atom and field are prepared in an excited and squeezed state, respectively. The non-classical properties of the field initially in the squeezed coherent states based on the evolution of the second-order correlation function. The study of entanglement between parts of a quantum system is done through the von Neumann entropy. We analyze the effect of the squeeze and detuning parameters on the dynamics of some field aspects and non-local correlation. The results obtained from this study show that the detuning parameter has an essential impact on the field properties.

Accounting for wire saggingоn span of 220 kV OHL whendetermining current, induced in ground wire by phase current magnetic fields

Overhead ground-wire cable (GW) is more prone to ice formation compared to 220 kV overhead lines. Ice-melting methods for GW using special power source have certain engineering constraints and required is connection of overhead line. Preventive heating of GW to above-zero temperature is an equivalent method to ice-melting. Preventive heating shall be provided by induction from electromagnetic field (EMF) of 220 kV overhead lines while in service. Induction methods of 220 kV OHL GW heating have been summarized and briefly described. Mathematical models of GW inductive heating do not consider the influence of wire and GW saggingon EMF parameters and equivalent circuit ground wire-earth. Therefore, sufficient mathematical model is required to use induction method of GW heating at 220 kV OHL segment. We propose induction heating for GW of double-circuit 220 kV OHL inclosed circuit ground wire-additional conductor top reventice formation. Mathematical model have been developed to calculate current, induced in circuit ground wire-additional conductor by magnetic fields of 220 kV OHL current while in service. Influence of wire and GW saggingon EMF parameters and equivalent circuit ground wire-additional conductor has been estimated. Due to mathematical model we could estimate induced current to prevent ice formation on GW of double-circuit 220 kV OHL while in service. Closed circuit ground wire-additional conductor is recommended for practical use, with capacitor loop included into circuit, its capacitance to be determined based on voltage resonance conditions.

Comparison of Circular and Linear Orthogonal Polarization Bases in Electromagnetic Field Parameters Measurement

Comparison of Circular and Linear Orthogonal Polarization Bases in Electromagnetic Field Parameters Measurement