WorldWideScience

Sample records for energy electromagnetic field

  1. Algebraic structure of general electromagnetic fields and energy flow

    International Nuclear Information System (INIS)

    Hacyan, Shahen

    2011-01-01

    Highlights: → Algebraic structure of general electromagnetic fields in stationary spacetime. → Eigenvalues and eigenvectors of the electomagnetic field tensor. → Energy-momentum in terms of eigenvectors and Killing vector. → Explicit form of reference frame with vanishing Poynting vector. → Application of formalism to Bessel beams. - Abstract: The algebraic structures of a general electromagnetic field and its energy-momentum tensor in a stationary space-time are analyzed. The explicit form of the reference frame in which the energy of the field appears at rest is obtained in terms of the eigenvectors of the electromagnetic tensor and the existing Killing vector. The case of a stationary electromagnetic field is also studied and a comparison is made with the standard short-wave approximation. The results can be applied to the general case of a structured light beams, in flat or curved spaces. Bessel beams are worked out as example.

  2. Vacuum energy of the electromagnetic field in a rotating system

    International Nuclear Information System (INIS)

    Hacyan, S.; Sarmiento, A.

    1986-01-01

    The vacuum energy of the electromagnetic field is calculated for a uniformly rotating observer. The spectrum of vacuum fluctuations is composed of the zero-point energy with a modified density of states and a contribution due to the rotation which is not thermal. (orig.)

  3. New theory of radiative energy transfer in free electromagnetic fields

    International Nuclear Information System (INIS)

    Wolf, E.

    1976-01-01

    A new theory of radiative energy transfer in free, statistically stationary electromagnetic fields is presented. It provides a model for energy transport that is rigorous both within the framework of the stochastic theory of the classical field as well as within the framework of the theory of the quantized field. Unlike the usual phenomenological model of radiative energy transfer that centers around a single scalar quantity (the specific intensity of radiation), our theory brings into evidence the need for characterizing the energy transport by means of two (related) quantities: a scalar and a vector that may be identified, in a well-defined sense, with ''angular components'' of the average electromagnetic energy density and of the average Poynting vector, respectively. Both of them are defined in terms of invariants of certain new electromagnetic correlation tensors. In the special case when the field is statistically homogeneous, our model reduces to the usual one and our angular component of the average electromagnetic energy density, when multiplied by the vacuum speed of light, then acquires all the properties of the specific intensity of radiation. When the field is not statistically homogeneous our model approximates to the usual phenomenological one, provided that the angular correlations between plane wave modes of the field extend over a sufficiently small solid angle of directions about the direction of propagation of each mode. It is tentatively suggested that, when suitably normalized, our angular component of the average electromagnetic energy density may be interpreted as a quasi-probability (general quantum-mechancial phase-space distribution function, such as Wigner's) for the position and the momentum of a photon

  4. Energy conservation law for randomly fluctuating electromagnetic fields

    International Nuclear Information System (INIS)

    Gbur, G.; Wolf, E.; James, D.

    1999-01-01

    An energy conservation law is derived for electromagnetic fields generated by any random, statistically stationary, source distribution. It is shown to provide insight into the phenomenon of correlation-induced spectral changes. The results are illustrated by an example. copyright 1999 The American Physical Society

  5. Energy-momentum tensor of the electromagnetic field

    International Nuclear Information System (INIS)

    Horndeski, G.W.; Wainwright, J.

    1977-01-01

    In this paper we investigate the energy-momentum tensor of the most general second-order vector-tensor theory of gravitation and electromagnetism which has field equations which are (i) derivable from a variational principle, (ii) consistent with the notion of conservation of charge, and (iii) compatible with Maxwell's equations in a flat space. This energy-momentum tensor turns out to be quadratic in the first partial derivatives of the electromagnetic field tensor and depends upon the curvature tensor. The asymptotic behavior of this energy-momentum tensor is examined for solutions to Maxwell's equations in Minkowski space, and it is demonstrated that this energy-momentum tensor predicts regions of negative energy density in the vicinity of point sources

  6. Energy flow in a bound electromagnetic field: resolution of apparent paradoxes

    International Nuclear Information System (INIS)

    Kholmetskii, A L; Yarman, T

    2008-01-01

    In this paper, we present a resolution of apparent paradoxes formulated in (Kholmetskii A L 2006 Apparent paradoxes in classical electrodynamics: the energy-momentum conservation law for a bound electromagnetic field Eur. J. Phys. 27 825-38; Kholmetskii A L and Yarman T 2008 Apparent paradoxes in classical electrodynamics: a fluid medium in an electromagnetic field Eur. J. Phys. 29 1127) and dealing with the energy flux in a bound electromagnetic field

  7. Continuity equations for bound electromagnetic field and the electromagnetic energy-momentum tensor

    International Nuclear Information System (INIS)

    Kholmetskii, A L; Missevitch, O V; Yarman, T

    2011-01-01

    We analyze the application of the Poynting theorem to the bound (velocity-dependent) electromagnetic (EM) field and show that an often-used arbitrary elimination of the term of self-interaction in the product j·E (where j is the current density and E the electric field) represents, in general, an illegitimate operation, which leads to incorrect physical consequences. We propose correct ways of eliminating the terms of self-interaction from the Poynting theorem to transform it into the form that is convenient for problems with bound EM field, which yield the continuity equations for the proper EM energy density, the interaction part of EM energy density and the total EM energy density of bound fields, respectively. These equations indicate the incompleteness of the common EM energy-momentum tensor, and in our analysis, we find a missed term in its structure, which makes its trace non-vanished. Some implications of these results are discussed, in particular, in view of the notion of EM mass of charged particles.

  8. Continuity equations for bound electromagnetic field and the electromagnetic energy-momentum tensor

    Energy Technology Data Exchange (ETDEWEB)

    Kholmetskii, A L [Department of Physics, Belarusian State University, 4 Nezavisimosti Avenue, 220030 Minsk (Belarus); Missevitch, O V [Institute for Nuclear Problems, Belarusian State University, 11 Bobruiskaya Street, 220030 Minsk (Belarus); Yarman, T, E-mail: khol123@yahoo.com [Department of Engineering, Okan University, Akfirat, Istanbul, Turkey and Savronik, Eskisehir (Turkey)

    2011-05-01

    We analyze the application of the Poynting theorem to the bound (velocity-dependent) electromagnetic (EM) field and show that an often-used arbitrary elimination of the term of self-interaction in the product j{center_dot}E (where j is the current density and E the electric field) represents, in general, an illegitimate operation, which leads to incorrect physical consequences. We propose correct ways of eliminating the terms of self-interaction from the Poynting theorem to transform it into the form that is convenient for problems with bound EM field, which yield the continuity equations for the proper EM energy density, the interaction part of EM energy density and the total EM energy density of bound fields, respectively. These equations indicate the incompleteness of the common EM energy-momentum tensor, and in our analysis, we find a missed term in its structure, which makes its trace non-vanished. Some implications of these results are discussed, in particular, in view of the notion of EM mass of charged particles.

  9. Electromagnetic fields in biological systems

    National Research Council Canada - National Science Library

    Lin, James C

    2012-01-01

    "Focusing on exposure, induced fields, and absorbed energy, this volume covers the interaction of electromagnetic fields and waves with biological systems, spanning static fields to terahertz waves...

  10. Energy-momentum tensor of intermediate vector bosons in an external electromagnetic field

    International Nuclear Information System (INIS)

    Mostepanenko, V.M.; Sokolov, I.Yu.

    1988-01-01

    Expressions are obtained for the canonical and metric energy-momentum tensors of the vector field of intermediate bosons in an external electromagnetic field. It is shown that in the case of a gyromagnetic ratio not equal to unity the energy-momentum tensor cannot be symmetrized on its indices, and an additional term proportional to the anomalous magnetic moment appears in the conservation laws. A modification of the canonical formalism for scalar and vector fields in an external field is proposed in accordance with which the Hamiltonian density is equal to the 00 component of the energy-momentum tensor. An expression for the energy-momentum tensor of a closed system containing a gauge field of intermediate bosons and an electromagnetic field is obtained

  11. Research and Evaluation of the Energy Flux Density of the Mobile Phone Electromagnetic Field

    Directory of Open Access Journals (Sweden)

    Pranas Baltrėnas

    2012-12-01

    Full Text Available The article analyses variations in the energy flux density of the electromagnetic field of 10 mobile phones depending on distance. The studies have been conducted using three modes: sending a text message, receiving a text message and connecting a mobile phone to the Internet. When text messages are received or sent from a mobile phone, the values of the energy flux density of the mobile phone electromagnetic field exceed the safe allowable limit and make 10 μW / cm². A distance of 10, 20 and 30 cm from a mobile phone is effective protection against the energy flux density of the electromagnetic field when writing texts, receiving messages or connecting to the mobile Internet.Article in Lithuanian

  12. Energy flux due to electromagnetic fluctuations during guide field magnetic reconnection

    International Nuclear Information System (INIS)

    Kuwahata, Akihiro; Inomoto, Michiaki; Ono, Yasushi; Yanai, Ryoma

    2016-01-01

    Large electromagnetic fluctuations inside the current sheet and large reconnection electric fields are observed during fast magnetic reconnection in the presence of a guide field. The fluctuations transport 2.5% of the dissipated magnetic energy from the reconnection region. Although the energy gains of the ions and electrons are approximately 60% and 12%, respectively, of the dissipated magnetic energy after the fast reconnection, the energy of fluctuations is not comparable to their energy gains. The fluctuations do not directly contribute to the energy conversion but might cause the fast reconnection leading to the rapid release of magnetic energy. (author)

  13. Absorption of electromagnetic field energy by superfluid system of atoms with electric dipole moment

    International Nuclear Information System (INIS)

    Poluektov, Yu.M.

    2014-01-01

    The modified Gross-Pitaevskii equation which takes into account relaxation and interaction with alternating electromagnetic field is used to consider the absorption of electromagnetic field energy by a superfluid system on the assumption that the atoms has intrinsic dipole moment. It is shown that the absorption may be of a resonant behavior only if the dispersion curves of the electromagnetic wave and the excitations of the superfluid system intersect. It is remarkable that such a situation is possible if the superfluid system has a branch of excitations with the energy gap at low momenta. The experiments on absorption of microwaves in superfluid helium are interpreted as evidence of existence of such gap excitations. A possible modification of the excitation spectrum of superfluid helium in the presence of excitation branch with energy gap is dis-cussed qualitatively

  14. Some consequences of the law of local energy conservation in electromagnetic field

    International Nuclear Information System (INIS)

    Beshtoev, Kh.M.

    2001-01-01

    At electromagnetic interactions of particles there arise defects of masses, i.e. the energy is liberated since the particles of the different charges are attracted. It is shown that this change of the effective mass of a particle in the external electric field (of a nucleus) results in displacement of atomic levels of electrons. The expressions describing these velocity changes and displacement of energy levels of electrons in the atom are obtained

  15. On the zero point energy of the electromagnetic field in the presence of material media

    International Nuclear Information System (INIS)

    Ferreira, L.A.

    1980-12-01

    The Van der Waals force between two semi-infinite material media separated by a piece of a third material is calculated. In this calculation, a generalization of some works on this theme is made, considering the radiation field delay effect, and impose no kind of electric and magnetic permeability dependence on the field frequency. The zero point energy of electromagnetic field in the presence of rectangular cavities with perfectly conducting walls (epsilon →i infinite) and/or infinitely permeable walls (μ→ infinite), is also calculated. Two kinds of regularization are made. In view of the results obtained modifications in the Casimir's model for the electron are suggested [pt

  16. Gauge-invariant expectation values of the energy of a molecule in an electromagnetic field

    International Nuclear Information System (INIS)

    Mandal, Anirban; Hunt, Katharine L. C.

    2016-01-01

    In this paper, we show that the full Hamiltonian for a molecule in an electromagnetic field can be separated into a molecular Hamiltonian and a field Hamiltonian, both with gauge-invariant expectation values. The expectation value of the molecular Hamiltonian gives physically meaningful results for the energy of a molecule in a time-dependent applied field. In contrast, the usual partitioning of the full Hamiltonian into molecular and field terms introduces an arbitrary gauge-dependent potential into the molecular Hamiltonian and leaves a gauge-dependent form of the Hamiltonian for the field. With the usual partitioning of the Hamiltonian, this same problem of gauge dependence arises even in the absence of an applied field, as we show explicitly by considering a gauge transformation from zero applied field and zero external potentials to zero applied field, but non-zero external vector and scalar potentials. We resolve this problem and also remove the gauge dependence from the Hamiltonian for a molecule in a non-zero applied field and from the field Hamiltonian, by repartitioning the full Hamiltonian. It is possible to remove the gauge dependence because the interaction of the molecular charges with the gauge potential cancels identically with a gauge-dependent term in the usual form of the field Hamiltonian. We treat the electromagnetic field classically and treat the molecule quantum mechanically, but nonrelativistically. Our derivation starts from the Lagrangian for a set of charged particles and an electromagnetic field, with the particle coordinates, the vector potential, the scalar potential, and their time derivatives treated as the variables in the Lagrangian. We construct the full Hamiltonian using a Lagrange multiplier method originally suggested by Dirac, partition this Hamiltonian into a molecular term H m and a field term H f , and show that both H m and H f have gauge-independent expectation values. Any gauge may be chosen for the calculations; but

  17. Electromagnetic wave energy converter

    Science.gov (United States)

    Bailey, R. L. (Inventor)

    1973-01-01

    Electromagnetic wave energy is converted into electric power with an array of mutually insulated electromagnetic wave absorber elements each responsive to an electric field component of the wave as it impinges thereon. Each element includes a portion tapered in the direction of wave propagation to provide a relatively wideband response spectrum. Each element includes an output for deriving a voltage replica of the electric field variations intercepted by it. Adjacent elements are positioned relative to each other so that an electric field subsists between adjacent elements in response to the impinging wave. The electric field results in a voltage difference between adjacent elements that is fed to a rectifier to derive dc output power.

  18. Coherent hybrid electromagnetic field imaging

    Science.gov (United States)

    Cooke, Bradly J [Jemez Springs, NM; Guenther, David C [Los Alamos, NM

    2008-08-26

    An apparatus and corresponding method for coherent hybrid electromagnetic field imaging of a target, where an energy source is used to generate a propagating electromagnetic beam, an electromagnetic beam splitting means to split the beam into two or more coherently matched beams of about equal amplitude, and where the spatial and temporal self-coherence between each two or more coherently matched beams is preserved. Two or more differential modulation means are employed to modulate each two or more coherently matched beams with a time-varying polarization, frequency, phase, and amplitude signal. An electromagnetic beam combining means is used to coherently combine said two or more coherently matched beams into a coherent electromagnetic beam. One or more electromagnetic beam controlling means are used for collimating, guiding, or focusing the coherent electromagnetic beam. One or more apertures are used for transmitting and receiving the coherent electromagnetic beam to and from the target. A receiver is used that is capable of square-law detection of the coherent electromagnetic beam. A waveform generator is used that is capable of generation and control of time-varying polarization, frequency, phase, or amplitude modulation waveforms and sequences. A means of synchronizing time varying waveform is used between the energy source and the receiver. Finally, a means of displaying the images created by the interaction of the coherent electromagnetic beam with target is employed.

  19. Landau Quasi-energy Spectrum Destruction for an Electron in Both a Static Magnetic Field and a Resonant Electromagnetic Wave

    International Nuclear Information System (INIS)

    Skoblin, A.A.

    1994-01-01

    Free nonrelativistic electrons in both a static magnetic field and an electromagnetic wave are considered. A plane-polarized wave propagates along a magnetic field, its frequency is close to the electron rotation frequency in a magnetic field. Electron spin is taken into account. An electron quasi energy spectrum and steady states (quasi energy states) are constructed. 6 refs

  20. Covariant electromagnetic field lines

    Science.gov (United States)

    Hadad, Y.; Cohen, E.; Kaminer, I.; Elitzur, A. C.

    2017-08-01

    Faraday introduced electric field lines as a powerful tool for understanding the electric force, and these field lines are still used today in classrooms and textbooks teaching the basics of electromagnetism within the electrostatic limit. However, despite attempts at generalizing this concept beyond the electrostatic limit, such a fully relativistic field line theory still appears to be missing. In this work, we propose such a theory and define covariant electromagnetic field lines that naturally extend electric field lines to relativistic systems and general electromagnetic fields. We derive a closed-form formula for the field lines curvature in the vicinity of a charge, and show that it is related to the world line of the charge. This demonstrates how the kinematics of a charge can be derived from the geometry of the electromagnetic field lines. Such a theory may also provide new tools in modeling and analyzing electromagnetic phenomena, and may entail new insights regarding long-standing problems such as radiation-reaction and self-force. In particular, the electromagnetic field lines curvature has the attractive property of being non-singular everywhere, thus eliminating all self-field singularities without using renormalization techniques.

  1. Strain Energy Density in the Elastodynamics of the Spacetime Continuum and the Electromagnetic Field

    Directory of Open Access Journals (Sweden)

    Millette P. A.

    2013-04-01

    Full Text Available We investigate the strain energy density of the spacetime continuum in the Elasto- dynamics of the Spacetime Continuum by applying continuum m echanical results to strained spacetime. The strain energy density is a scalar. W e find that it is separated into two terms: the first one expresses the dilatation energy density (the “mass” longitu- dinal term while the second one expresses the distortion en ergy density (the “massless” transverse term. The quadratic structure of the energy rel ation of Special Relativity is found to be present in the theory. In addition, we find that the kinetic energy pc is car- ried by the distortion part of the deformation, while the dil atation part carries only the rest-mass energy. The strain energy density of the electrom agnetic energy-momentum stress tensor is calculated. The dilatation energy density (the rest-mass energy density of the photon is found to be 0 as expected. The transverse dis tortion energy density is found to include a longitudinal electromagnetic energy fl ux term, from the Poynting vector, that is massless as it is due to distortion, not dilatation, of the spacetime con- tinuum. However, because this energy flux is along the direct ion of propagation (i.e. longitudinal, it gives rise to the particle aspect of the el ectromagnetic field, the photon.

  2. The classical electromagnetic field

    CERN Document Server

    Eyges, Leonard

    2010-01-01

    This excellent text covers a year's course in advanced theoretical electromagnetism, first introducing theory, then its application. Topics include vectors D and H inside matter, conservation laws for energy, momentum, invariance, form invariance, covariance in special relativity, and more.

  3. Electromagnetic field effects on Υ-meson dissociation in PbPb collisions at LHC energies

    Energy Technology Data Exchange (ETDEWEB)

    Hoelck, J.; Wolschin, G. [Institut fuer Theoretische Physik der Universitaet Heidelberg (Germany)

    2017-12-15

    We investigate the effect of the electromagnetic field generated in relativistic heavy-ion collisions on the dissociation of Υ mesons. The electromagnetic field is calculated using a simple model which characterizes the emerging quark-gluon plasma (QGP) by its conductivity only. A numerical estimate of the field strength experienced by Υ mesons embedded in the expanding QGP and its consequences on the Υ dissociation is made. The electromagnetic field effects prove to be negligible compared to the established strong-interaction suppression mechanisms. (orig.)

  4. Healing of damaged metal by a pulsed high-energy electromagnetic field

    Science.gov (United States)

    Kukudzhanov, K. V.; Levitin, A. L.

    2018-04-01

    The processes of defect (intergranular micro-cracks) transformation are investigated for metal samples in a high-energy short-pulsed electromagnetic field. This investigation is based on a numerical coupled model of the impact of high-energy electromagnetic field on the pre-damaged thermal elastic-plastic material with defects. The model takes into account the melting and evaporation of the metal and the dependence of its physical and mechanical properties on the temperature. The system of equations is solved numerically by finite element method with an adaptive mesh using the arbitrary Euler–Lagrange method. The calculations show that the welding of the crack and the healing of micro-defects under treatment by short pulses of the current takes place. For the macroscopic description of the healing process, the healing and damage parameters of the material are introduced. The healing of micro-cracks improves the material healing parameter and reduces its damage. The micro-crack shapes practically do not affect the time-dependence of the healing and damage under the treatment by the current pulses. These changes are affected only by the value of the initial damage of the material and the initial length of the micro-crack. The time-dependence of the healing and the damage is practically the same for all different shapes of micro-defects, provided that the initial lengths of micro-cracks and the initial damages are the same for these different shapes of defects.

  5. Quantum energy teleportation with an electromagnetic field: discrete versus continuous variables

    International Nuclear Information System (INIS)

    Hotta, Masahiro

    2010-01-01

    It is well known that usual quantum teleportation protocols cannot transport energy. Recently, new protocols called quantum energy teleportation (QET) have been proposed, which transport energy by local operations and classical communication with the ground states of many-body quantum systems. In this paper, we compare two different QET protocols for transporting energy with the electromagnetic field. In the first protocol, a 1/2 spin (a qubit) is coupled with the quantum fluctuation in the vacuum state and measured in order to obtain one-bit information about the fluctuation for the teleportation. In the second protocol, a harmonic oscillator is coupled with the fluctuation and measured in order to obtain continuous-variable information about the fluctuation. In the spin protocol, the amount of teleported energy is suppressed by an exponential damping factor when the amount of input energy increases. This suppression factor becomes power damping in the case of the harmonic oscillator protocol. Therefore, it is concluded that obtaining more information about the quantum fluctuation leads to teleporting more energy. This result suggests a profound relationship between energy and quantum information.

  6. Energy Harvesting from the Stray Electromagnetic Field around the Electrical Power Cable for Smart Grid Applications.

    Science.gov (United States)

    Khan, Farid Ullah

    For wireless sensor node (WSN) applications, this paper presents the harvesting of energy from the stray electromagnetic field around an electrical power line. Inductive and capacitive types of electrodynamic energy harvesters are developed and reported. For the produced energy harvesters, solid core and split-core designs are adopted. The inductive energy harvester comprises a copper wound coil which is produced on a mild steel core. However, the capacitive prototypes comprise parallel, annular discs separated by Teflon spacers. Moreover, for the inductive energy harvesters' wound coil and core, the parametric analysis is also performed. A Teflon housing is incorporated to protect the energy harvester prototypes from the harsh environmental conditions. Among the inductive energy harvesters, prototype-5 has performed better than the other harvesters and produces a maximum rms voltage of 908 mV at the current level of 155 A in the power line. However, at the same current flow, the capacitive energy harvesters produce a maximum rms voltage of 180 mV. The alternating output of the prototype-5 is rectified, and a super capacitor (1 F, 5.5 V) and rechargeable battery (Nickel-Cadmium, 3.8 V) are charged with it. Moreover, with the utilization of a prototype-5, a self-powered wireless temperature sensing and monitoring system for an electrical transformer is also developed and successfully implemented.

  7. Forces in electromagnetic field and gravitational field

    OpenAIRE

    Weng, Zihua

    2008-01-01

    The force can be defined from the linear momentum in the gravitational field and electromagnetic field. But this definition can not cover the gradient of energy. In the paper, the force will be defined from the energy and torque in a new way, which involves the gravitational force, electromagnetic force, inertial force, gradient of energy, and some other new force terms etc. One of these new force terms can be used to explain why the solar wind varies velocity along the magnetic force line in...

  8. High energy pair production in arbitrary configuration of intense electromagnetic fields

    International Nuclear Information System (INIS)

    Ayasli, S.; Hacinliyan, A.

    1978-01-01

    The photon attenuation coefficient for pair production in intense electric and magnetic fields of arbitrary confiquration is derived. The results are applied to a cascade calculation of electromagnetic processes in pulsars. (author)

  9. The total energy-momentum tensor for electromagnetic fields in a dielectric

    Science.gov (United States)

    Crenshaw, Michael E.

    2017-08-01

    Radiation pressure is an observable consequence of optically induced forces on materials. On cosmic scales, radiation pressure is responsible for the bending of the tails of comets as they pass near the sun. At a much smaller scale, optically induced forces are being investigated as part of a toolkit for micromanipulation and nanofabrication technology [1]. A number of practical applications of the mechanical effects of light-matter interaction are discussed by Qiu, et al. [2]. The promise of the nascent nanophotonic technology for manufacturing small, low-power, high-sensitivity sensors and other devices has likely motivated the substantial current interest in optical manipulation of materials at the nanoscale, see, for example, Ref. [2] and the references therein. While substantial progress toward optical micromanipulation has been achieved, e.g. optical tweezers [1], in this report we limit our consideration to the particular issue of optically induced forces on a transparent dielectric material. As a matter of electromagnetic theory, these forces remain indeterminate and controversial. Due to the potential applications in nanotechnology, the century-old debate regarding these forces, and the associated momentums, has ramped up considerably in the physics community. The energy-momentum tensor is the centerpiece of conservation laws for the unimpeded, inviscid, incompressible flow of non-interacting particles in the continuum limit in an otherwise empty volume. The foundations of the energy-momentum tensor and the associated tensor conservation theory come to electrodynamics from classical continuum dynamics by applying the divergence theorem to a Taylor series expansion of a property density field of a continuous flow in an otherwise empty volume. The dust tensor is a particularly simple example of an energy-momentum tensor that deals with particles of matter in the continuum limit in terms of the mass density ρm, energy density ρmc 2 , and momentum density

  10. Pregnancy and electromagnetic fields

    International Nuclear Information System (INIS)

    Bisseriex, Ch.; Laurent, P.; Cabaret, Ph.; Bonnet, C.; Marteau, E.; Le Berre, G.; Tirlemont, S.; Castro, H.; Becker, A.; Demaret, Ph.; Donati, M.; Ganem, Y.; Moureaux, P.

    2011-07-01

    This document briefly indicates the status of knowledge regarding the effect of magnetic fields on biological tissues and pregnancy, outlines the lack of data on some frequencies and the weakness of studies on long term effects on child development. It evokes the issue of exposure assessment and that of identification of workstations exposed to electromagnetic fields

  11. Electromagnetic fields and their impacts

    Science.gov (United States)

    Prša, M. A.; Kasaš-Lažetić, K. K.

    2018-01-01

    The main goal of this paper is to briefly recall some different electromagnetic field definitions, some macroscopic sources of electromagnetic fields, electromagnetic fields classification regarding time dependences, and the ways of field determination in concrete cases. After that, all the mechanisms of interaction between electromagnetic field and substance, on atomic level, are described in details. Interaction between substance and electric field is investigated separately from the substance and magnetic field interaction. It is demonstrated that, in all cases of the unique electromagnetic field, total interaction can be treated as a superposition of two separated interactions. Finally, the main electromagnetic fields surrounding us is cited and discussed.

  12. Moving Manifolds in Electromagnetic Fields

    Directory of Open Access Journals (Sweden)

    David V. Svintradze

    2017-08-01

    Full Text Available We propose dynamic non-linear equations for moving surfaces in an electromagnetic field. The field is induced by a material body with a boundary of the surface. Correspondingly the potential energy, set by the field at the boundary can be written as an addition of four-potential times four-current to a contraction of the electromagnetic tensor. Proper application of the minimal action principle to the system Lagrangian yields dynamic non-linear equations for moving three dimensional manifolds in electromagnetic fields. The equations in different conditions simplify to Maxwell equations for massless three surfaces, to Euler equations for a dynamic fluid, to magneto-hydrodynamic equations and to the Poisson-Boltzmann equation.

  13. Prediction of the Electromagnetic Field Distribution in a Typical Aircraft Using the Statistical Energy Analysis

    Science.gov (United States)

    Kovalevsky, Louis; Langley, Robin S.; Caro, Stephane

    2016-05-01

    Due to the high cost of experimental EMI measurements significant attention has been focused on numerical simulation. Classical methods such as Method of Moment or Finite Difference Time Domain are not well suited for this type of problem, as they require a fine discretisation of space and failed to take into account uncertainties. In this paper, the authors show that the Statistical Energy Analysis is well suited for this type of application. The SEA is a statistical approach employed to solve high frequency problems of electromagnetically reverberant cavities at a reduced computational cost. The key aspects of this approach are (i) to consider an ensemble of system that share the same gross parameter, and (ii) to avoid solving Maxwell's equations inside the cavity, using the power balance principle. The output is an estimate of the field magnitude distribution in each cavity. The method is applied on a typical aircraft structure.

  14. Clinical importance of electromagnetic fields

    International Nuclear Information System (INIS)

    Ruppe, I.

    1993-01-01

    The clinical importance of most of the electromagnetic fields is not highly. Mostly they only have thermal effects, produced by energy-absorption. About 1 C increase of whole-body-temperature is valid for tolerable limit. For measuring is used the SAR-Value (Specific Absorption Rate) in W/kg body mass. SAR = 0,8W/kg for the whole body is valid to be safety. For the evaluation of possible other effects of electromagnetic fields the scientific knowledges are till now not sufficient to allow a final statement. That could be impacts of electromagnetic fields to conduction or switch processes in the nerves or brains, in the framwork of cellular regulations, in the genetic reactions are occurig is little, but if is necessary to find it out in scinentific investigations. (orig.) [de

  15. Momentum-energy of the non-radiating electromagnetic field: open problems?

    International Nuclear Information System (INIS)

    Kholmetskii, Alexander L

    2006-01-01

    This paper inspects more closely the problem of the momentum and energy of a bound (non-radiative) electromagnetic (EM) field. It has been shown that for an isolating system of non-radiative non-relativistic mechanically free charged particles, a transformation of mechanical to EM momentum and vice versa occurs in accordance with the requirement P-vector G =const, where P-vector G = P-vector M + Σ i N q i A-vector i is the canonical momentum (N>1 is the number of particles, q is the charge, A-vector is the vector potential, P-vector M is the mechanical momentum of the system). Then dP-vector M /dt = -(d/dt)Σq i A-vector i represents the self-force, acting on this isolating system due to violation of Newton's third law in EM interaction. This equation is not applicable to an isolated charged particle, and the problems of its self-action and its own EM momentum have been examined. Analysing the systems of non-radiative particles, where the retardation is not negligible ('dynamical' systems in our definition) it has been found that the total momentum is the same at the initial and final stationary states of such systems, but it varies with time during the dynamical processes. It means a violation of continuous conservation of the total momentum, if the bound EM field spreads at the light velocity c. Finally, the compatibility of the energy conservation law and the Lentz rule for retarded non-radiative EM field has been examined. It has been shown that for dynamical systems the energy conservation law comes into a certain contradiction with the finite (light) spread velocity for the bound EM field

  16. Electromagnetic fields and waves

    CERN Document Server

    Iskander, Magdy F

    2013-01-01

    The latest edition of Electromagnetic Fields and Waves retains an authoritative, balanced approach, in-depth coverage, extensive analysis, and use of computational techniques to provide a complete understanding of electromagnetic—important to all electrical engineering students. An essential feature of this innovative text is the early introduction of Maxwell's equations, together with the quantifying experimental observations made by the pioneers who discovered electromagnetics. This approach directly links the mathematical relations in Maxwell's equations to real experiments and facilitates a fundamental understanding of wave propagation and use in modern practical applications, especially in today's wireless world. New and expanded topics include the conceptual relationship between Coulomb's law and Gauss's law for calculating electric fields, the relationship between Biot-Savart's and Ampere's laws and their use in calculating magnetic fields from current sources, the development of Faraday's law from e...

  17. Causal extraction of black hole rotational energy by various kinds of electromagnetic fields

    International Nuclear Information System (INIS)

    Koide, Shinji; Baba, Tamon

    2014-01-01

    Recent general relativistic magnetohydrodynamics (MHD) simulations have suggested that relativistic jets from active galactic nuclei (AGNs) have been powered by the rotational energy of central black holes. Some mechanisms for extraction of black hole rotational energy have been proposed, like the Penrose process, Blandford-Znajek mechanism, MHD Penrose process, and superradiance. The Blandford-Znajek mechanism is the most promising mechanism for the engines of the relativistic jets from AGNs. However, an intuitive interpretation of this mechanism with causality is not yet clarified, while the Penrose process has a clear interpretation for causal energy extraction from a black hole with negative energy. In this paper, we present a formula to build physical intuition so that in the Blandford-Znajek mechanism, as well as in other electromagnetic processes, negative electromagnetic energy plays an important role in causal extraction of the rotational energy of black holes.

  18. Proposed electromagnetic wave energy converter

    Science.gov (United States)

    Bailey, R. L.

    1973-01-01

    Device converts wave energy into electric power through array of insulated absorber elements responsive to field of impinging electromagnetic radiation. Device could also serve as solar energy converter that is potentially less expensive and fragile than solar cells, yet substantially more efficient.

  19. Comment on ''Vacuum stress-energy tensor of the electromagnetic field in rotating frames''

    International Nuclear Information System (INIS)

    Mane, S.R.

    1991-01-01

    Hacyan and Sarmiento have found that an observer accelerating in a circle will detect a nonzero energy flux (Poynting vector) caused by the vacuum electromagnetic fluctuations in that frame. I wish to suggest that the above flux is related to synchrotron radiation. I treat only the leading order of perturbation theory

  20. Low frequency electromagnetic field sensor

    International Nuclear Information System (INIS)

    Zhu Min; Zhou Yan; He Yicheng; Zheng Zhenxing; Liu Sunkun

    2000-01-01

    The measurement technique of low frequency electromagnetic field is reported. According to this principle, the authors have designed a sensor, which is used to measure the natural electromagnetic field, SLEMP and electromagnetic signals generated by some explosions. The frequency band of this sensor is from 0.08 Hz to 2 MHz

  1. Electromagnetic Fields in Reverberant Environments

    NARCIS (Netherlands)

    Vogt-Ardatjew, Robert Andrzej

    2017-01-01

    The phenomenon of resonating electromagnetic (EM) fields has been commonly and successfully exploited in reverberation chambers (RC) for the purpose of electromagnetic compatibility (EMC) testing, as well as modeling multipath environments. Although largely successful, the currently used statistical

  2. Electromagnetic fields and life

    CERN Document Server

    Presman, A S

    1970-01-01

    A broad region of the electromagnetic spectrum long assumed to have no influence on living systems under natural conditions has been critically re-examined over the past decade. This spectral region extends from the superhigh radio frequencies, through de­ creasing frequencies, to and including essentially static electric and magnetic fields. The author of this monograph, A. S. Presman, has reviewed not only the extensive Russian literatur!;"l, but also al­l most equally comprehensively the non-Russian literature, dealing with biological influences of these fields. Treated also is literature shedding some light on possible theoretical foundations for these phenomena. A substantial, rapidly increasing number of studies in many laboratories and countries has now clearly established bio­ logical influences which are independent of the theoretically predictable, simple thermal effects. Indeed many of the effects are produced by field strengths very close to those within the natural environment. The author has,...

  3. Electrons in a relativistic-intensity laser field: generation of zeptosecond electromagnetic pulses and energy spectrum of the accelerated electrons

    International Nuclear Information System (INIS)

    Andreev, A A; Galkin, A L; Kalashnikov, M P; Korobkin, V V; Romanovsky, Mikhail Yu; Shiryaev, O B

    2011-01-01

    We study the motion of an electron and emission of electromagnetic waves by an electron in the field of a relativistically intense laser pulse. The dynamics of the electron is described by the Newton equation with the Lorentz force in the right-hand side. It is shown that the electrons may be ejected from the interaction region with high energy. The energy spectrum of these electrons and the technique of using the spectrum to assess the maximal intensity in the focus are analysed. It is found that electromagnetic radiation of an electron moving in an intense laser field occurs within a small angle around the direction of the electron trajectory tangent. The tangent quickly changes its direction in space; therefore, electromagnetic radiation of the electron in the far-field zone in a certain direction in the vicinity of the tangent is a short pulse with a duration as short as zeptoseconds. The calculation of the temporary and spectral distribution of the radiation field is carried out. (superintense laser fields)

  4. Electromagnetic fields and cancer

    International Nuclear Information System (INIS)

    Singh, Neeta; Mathur, R.; Behari, J.

    1997-01-01

    Several studies in recent years have raised the possibility that exposure to electromagnetic fields (EMFs) may be hazardous to human health, in particular by promotion or initiation of cancer. Recent reports have indicated increased cancer risk from industrial and domestic exposure to environmental ELF fields and to RF fields that are amplitude modulated at ELF. EMF fields have been reported to affect biological systems in various ways, affecting changes in the morphology and or functional behavior of cells, which have been observed in a variety of tissues. Although the mechanism of interaction of EMFs with living cells are not known, it has been proposed that they have multiple effects and can affect cell signalling, including modification of plasma membrane permeability and ion transport. Our findings suggest that EMFs can affect post translational modification of proteins such as poly ADP-ribosylation by epigenetic mechanism and that the effect of EMFs are highly specific regarding both the cell type and the frequency and amplification of the applied field. (author)

  5. Electromagnetic Fields Exposure Limits

    Science.gov (United States)

    2018-01-01

    Mr. T.P. (Tjerk) KUIPERS Senior Adviser Health Physics Military Healthcare & Occupational Health Expertise Co-ordination Centre Support...Test of Biological Integrity in Dogs Exposed to an Electromagnetic Pulse Environment”, Health Physics 36:159-165, 1979. [11] Baum, S.J., Ekstrom, M.E...Electromagnetic Radiation”, Health Physics 30:161-166, 1976. [12] Baum, S., Skidmore, W. and Ekstrom, M., “Continuous Exposure of Rodents to 108 Pulses

  6. Electromagnetic field sources in radiofrequency

    International Nuclear Information System (INIS)

    Oliveira, C.; Sebastiao, D.; Ladeira, D.; Antunes, M.; Correia, L.M.

    2010-01-01

    In the scope of the monIT Project, several measurements were made of electromagnetic fields in Portugal. This paper presents an analysis of the sources operating in the radiofrequency range, resulting from 2429 measurements in 466 locations.

  7. Time dependence of the field energy densities surrounding sources: Application to scalar mesons near point sources and to electromagnetic fields near molecules

    International Nuclear Information System (INIS)

    Persico, F.; Power, E.A.

    1987-01-01

    The time dependence of the dressing-undressing process, i.e., the acquiring or losing by a source of a boson field intensity and hence of a field energy density in its neighborhood, is considered by examining some simple soluble models. First, the loss of the virtual field is followed in time when a point source is suddenly decoupled from a neutral scalar meson field. Second, an initially bare point source acquires a virtual meson cloud as the coupling is switched on. The third example is that of an initially bare molecule interacting with the vacuum of the electromagnetic field to acquire a virtual photon cloud. In all three cases the dressing-undressing is shown to take place within an expanding sphere of radius r = ct centered at the source. At each point in space the energy density tends, for large times, to that of the ground state of the total system. Differences in the time dependence of the dressing between the massive scalar field and the massless electromagnetic field are discussed. The results are also briefly discussed in the light of Feinberg's ideas on the nature of half-dressed states in quantum field theory

  8. Intermediate energy electromagnetic interactions

    International Nuclear Information System (INIS)

    Garcon, M.

    1994-11-01

    Polarization measurements in electromagnetic interactions are reviewed. Deep inelastic scattering of polarized electrons and muons an polarized targets, photoproduction of pseudoscalar mesons on protons, photonuclear reactions, and the electromagnetic structure of the deuteron are discussed. (K.A.)

  9. Intermediate energy electromagnetic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Garcon, M.

    1994-11-01

    Polarization measurements in electromagnetic interactions are reviewed. Deep inelastic scattering of polarized electrons and muons an polarized targets, photoproduction of pseudoscalar mesons on protons, photonuclear reactions, and the electromagnetic structure of the deuteron are discussed. (K.A.).

  10. Gauge invariant fractional electromagnetic fields

    International Nuclear Information System (INIS)

    Lazo, Matheus Jatkoske

    2011-01-01

    Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators. -- Highlights: → We propose a fractional Lagrangian formulation for fractional Maxwell's fields. → We obtain gauge invariant fractional electromagnetic fields. → Our generalized fractional Maxwell's field is spatially symmetrical. → We discuss the non-causality of the theory.

  11. Gauge invariant fractional electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Lazo, Matheus Jatkoske, E-mail: matheuslazo@furg.br [Instituto de Matematica, Estatistica e Fisica - FURG, Rio Grande, RS (Brazil)

    2011-09-26

    Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators. -- Highlights: → We propose a fractional Lagrangian formulation for fractional Maxwell's fields. → We obtain gauge invariant fractional electromagnetic fields. → Our generalized fractional Maxwell's field is spatially symmetrical. → We discuss the non-causality of the theory.

  12. Gauge invariant fractional electromagnetic fields

    Science.gov (United States)

    Lazo, Matheus Jatkoske

    2011-09-01

    Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators.

  13. Biological effects of electromagnetic fields

    International Nuclear Information System (INIS)

    David, E.

    1993-01-01

    In this generally intelligible article, the author describes at first the physical fundamentals of electromagnetic fields and their basic biological significance and effects for animals and human beings before dealing with the discussion regarding limiting values and dangers. The article treats possible connections with leukaemia as well as ith melatonine production more detailed. (vhe) [de

  14. Tracking Electromagnetic Energy With SQUIDs

    Science.gov (United States)

    2005-01-01

    A superconducting quantum interference device (SQUID) is a gadget used to measure extremely weak signals, specifically magnetic flux. It can detect subtle changes in energy, up to 100 billion times weaker than the electromagnetic energy required to move a compass needle. SQUIDs are used for a variety of testing procedures where extreme sensitivity is required and where the test instrument need not come into direct contact with the test subject. NASA uses SQUIDs for remote, noncontact sensing in a variety of venues, including monitoring the Earth s magnetic field and tracking brain activity of pilots. Scientists at NASA s Goddard Space Flight Center have been making extensive use of this technology, from astrophysical research, to tracking the navigational paths of bees in flight to determine if they are using internal compasses. These very sensitive measurement devices have a wide variety of uses within NASA and even more uses within the commercial realm.

  15. Electromagnetic radiation from positive-energy bound electrons in the Coulomb field of a nucleus at rest in a strong uniform magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Arsenyev, S. A.; Koryagin, S. A., E-mail: koryagin@appl.sci-nnov.ru [Russian Academy of Sciences, Institute of Applied Physics (Russian Federation)

    2012-06-15

    A classical analysis is presented of the electromagnetic radiation emitted by positive-energy electrons performing bound motion in the Coulomb field of a nucleus at rest in a strong uniform magnetic field. Bounded trajectories exist and span a wide range of velocity directions near the nucleus (compared to free trajectories with similar energies) when the electron Larmor radius is smaller than the distance at which the electron-nucleus Coulomb interaction energy is equal to the mechanical energy of an electron. The required conditions occur in magnetic white dwarf photospheres and have been achieved in experiments on production of antihydrogen. Under these conditions, the radiant power per unit volume emitted by positive-energy bound electrons is much higher than the analogous characteristic of bremsstrahlung (in particular, in thermal equilibrium) at frequencies that are below the electron cyclotron frequency but higher than the inverse transit time through the interaction region in a close collision in the absence of a magnetic field. The quantum energy discreteness of positive-energy bound states restricts the radiation from an ensemble of bound electrons (e.g., in thermal equilibrium) to nonoverlapping spectral lines, while continuum radiative transfer is dominated by linearly polarized bremsstrahlung.

  16. Electromagnetic Fields and Cancer

    Science.gov (United States)

    ... and magnetic fields (1 Hz to 100 kHz) . Health Physics 2010; 99(6):818-36. doi: 10.1097/ ... and health: review of current status of research. Health Physics 2013; 105(6):561-75. [PubMed Abstract] AGNIR. ...

  17. What Are Electromagnetic Fields?

    Science.gov (United States)

    ... field causes a compass needle to orient in a North-South direction and is used by birds and fish for navigation. Human-made sources of ... and form the basis of telecommunications as well as radio and television ... In microwaves ovens, we use them to quickly heat food. At ...

  18. Note on Inverse Bremsstrahlung in a Strong Electromagnetic Field

    Science.gov (United States)

    Bethe, H. A.

    1972-09-01

    The collisional energy loss of an electron undergoing forced oscillation in an electromagnetic field behaves quite differently in the low and high intensity limits. ... It is shown that in the case of an electromagnetic field v {sub o} >> v {sub t} the rate of transfer is much slower, and actually decreases with the strength of the field.

  19. Electromagnetic Fields and Public Health: Mobile Phones

    Science.gov (United States)

    ... waves through a network of fixed antennas called base stations. Radiofrequency waves are electromagnetic fields, and unlike ionizing radiation ... waves through a network of fixed antennas called base stations. Radiofrequency waves are electromagnetic fields, and unlike ionizing radiation ...

  20. A System for Electromagnetic Field Conversion

    DEFF Research Database (Denmark)

    2003-01-01

    A system is provided for conversion of a first electromagnetic field into a desired second electromagnetic field, for example for coupling modes between waveguides or into microstructured waveguides. The system comprises a complex spatial electromagnetic field converter that is positioned...... for reception of at least a part of the first electromagnetic field and that is adapted for conversion of the received field into the desired electromagnetic field, and wherein at least one of the first and second fields matches a mode of a microstructured waveguide. It is an important advantage of the present...

  1. Motion of charged particles in a knotted electromagnetic field

    International Nuclear Information System (INIS)

    Arrayas, M; Trueba, J L

    2010-01-01

    In this paper we consider the classical relativistic motion of charged particles in a knotted electromagnetic field. After reviewing how to construct electromagnetic knots from maps between the three-sphere and the two-sphere, we introduce a mean quadratic radius of the energy density distribution in order to study some properties of this field. We study the classical relativistic motion of electrons in the electromagnetic field of the Hopf map, and compute their trajectories. It is observed that these electrons initially at rest are strongly accelerated by the electromagnetic force, becoming ultrarelativistic in a period of time that depends on the knot energy and size.

  2. Motion of charged particles in a knotted electromagnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Arrayas, M; Trueba, J L, E-mail: joseluis.trueba@urjc.e [Area de Electromagnetismo, Universidad Rey Juan Carlos, Camino del Molino s/n, 28943 Fuenlabrada, Madrid (Spain)

    2010-06-11

    In this paper we consider the classical relativistic motion of charged particles in a knotted electromagnetic field. After reviewing how to construct electromagnetic knots from maps between the three-sphere and the two-sphere, we introduce a mean quadratic radius of the energy density distribution in order to study some properties of this field. We study the classical relativistic motion of electrons in the electromagnetic field of the Hopf map, and compute their trajectories. It is observed that these electrons initially at rest are strongly accelerated by the electromagnetic force, becoming ultrarelativistic in a period of time that depends on the knot energy and size.

  3. Global observations of electromagnetic and particle energy flux for an event during northern winter with southward interplanetary magnetic field

    Directory of Open Access Journals (Sweden)

    H. Korth

    2008-06-01

    Full Text Available The response of the polar ionosphere–thermosphere (I-T system to electromagnetic (EM energy input is fundamentally different to that from particle precipitation. To understand the I-T response to polar energy input one must know the intensities and spatial distributions of both EM and precipitation energy deposition. Moreover, since individual events typically display behavior different from statistical models, it is important to observe the global system state for specific events. We present an analysis of an event in Northern Hemisphere winter for sustained southward interplanetary magnetic field (IMF, 10 January 2002, 10:00–12:00 UT, for which excellent observations are available from the constellation of Iridium satellites, the SuperDARN radar network, and the Far-Ultraviolet (FUV instrument on the IMAGE satellite. Using data from these assets we determine the EM and particle precipitation energy fluxes to the Northern Hemisphere poleward of 60° MLAT and examine their spatial distributions and intensities. The accuracy of the global estimates are assessed quantitatively using comparisons with in-situ observations by DMSP along two orbit planes. While the location of EM power input evaluated from Iridium and SuperDARN data is in good agreement with DMSP, the magnitude estimated from DMSP observations is approximately four times larger. Corrected for this underestimate, the total EM power input to the Northern Hemisphere is 188 GW. Comparison of IMAGE FUV-derived distributions of the particle energy flux with DMSP plasma data indicates that the IMAGE FUV results similarly locate the precipitation accurately while underestimating the precipitation input somewhat. The total particle input is estimated to be 20 GW, nearly a factor of ten lower than the EM input. We therefore expect the thermosphere response to be determined primarily by the EM input even under winter conditions, and accurate assessment of the EM energy input is therefore key

  4. Perturbations in electromagnetic dark energy

    International Nuclear Information System (INIS)

    Jiménez, Jose Beltrán; Maroto, Antonio L.; Koivisto, Tomi S.; Mota, David F.

    2009-01-01

    It has been recently proposed that the presence of a temporal electromagnetic field on cosmological scales could explain the phase of accelerated expansion that the universe is currently undergoing. The field contributes as a cosmological constant and therefore, the homogeneous cosmology produced by such a model is exactly the same as that of ΛCDM. However, unlike a cosmological constant term, electromagnetic fields can acquire perturbations which in principle could affect CMB anisotropies and structure formation. In this work, we study the evolution of inhomogeneous scalar perturbations in this model. We show that provided the initial electromagnetic fluctuations generated during inflation are small, the model is perfectly compatible with both CMB and large scale structure observations at the same level of accuracy as ΛCDM

  5. Coherent polarization driven by external electromagnetic fields

    International Nuclear Information System (INIS)

    Apostol, M.; Ganciu, M.

    2010-01-01

    The coherent interaction of the electromagnetic radiation with an ensemble of polarizable, identical particles with two energy levels is investigated in the presence of external electromagnetic fields. The coupled non-linear equations of motion are solved in the stationary regime and in the limit of small coupling constants. It is shown that an external electromagnetic field may induce a macroscopic occupation of both the energy levels of the particles and the corresponding photon states, governed by a long-range order of the quantum phases of the internal motion (polarization) of the particles. A lasing effect is thereby obtained, controlled by the external field. Its main characteristics are estimated for typical atomic matter and atomic nuclei. For atomic matter the effect may be considerable (for usual external fields), while for atomic nuclei the effect is extremely small (practically insignificant), due to the great disparity in the coupling constants. In the absence of the external field, the solution, which is non-analytic in the coupling constant, corresponds to a second-order phase transition (super-radiance), which was previously investigated.

  6. Particle physics in intense electromagnetic fields

    International Nuclear Information System (INIS)

    Kurilin, A.V.

    1999-01-01

    The quantum field theory in the presence of classical background electromagnetic field is reviewed giving a pedagogical introduction to the Feynman-Furry method of describing non-perturbative interactions with very strong electromagnetic fields. A particular emphasis is given to the case of the plane-wave electromagnetic field for which the charged particles' wave functions and propagators are presented. Some general features of quantum processes proceeding in the intense electromagnetic background are argued. The possibilities of searching new physics through the investigations of quantum phenomena induced by a strong electromagnetic environment are also discussed

  7. Electromagnetic fields, environment and health

    CERN Document Server

    Perrin, Anne

    2013-01-01

    A good number of false ideas are circulating on the effects of non-ionizing radiations on our health, which can lead to an oversimplification of the issue, to potentially dangerous misconceptions or to misleading data analysis. Health effects may be exaggerated, or on the contrary underplayed. The authors of this work (doctors, engineers and researchers) have endeavored to supply validated and easily understandable scientific information on the electromagnetic fields and their biological and health effects. After a general review of the physics of the waves and a presentation of non-ionizing r

  8. Numerical analysis of electromagnetic fields

    CERN Document Server

    Zhou Pei Bai

    1993-01-01

    Numerical methods for solving boundary value problems have developed rapidly. Knowledge of these methods is important both for engineers and scientists. There are many books published that deal with various approximate methods such as the finite element method, the boundary element method and so on. However, there is no textbook that includes all of these methods. This book is intended to fill this gap. The book is designed to be suitable for graduate students in engineering science, for senior undergraduate students as well as for scientists and engineers who are interested in electromagnetic fields. Objective Numerical calculation is the combination of mathematical methods and field theory. A great number of mathematical concepts, principles and techniques are discussed and many computational techniques are considered in dealing with practical problems. The purpose of this book is to provide students with a solid background in numerical analysis of the field problems. The book emphasizes the basic theories ...

  9. Electromagnetic field effects in explosives

    Science.gov (United States)

    Tasker, Douglas

    2009-06-01

    Present and previous research on the effects of electromagnetic fields on the initiation and detonation of explosives and the electromagnetic properties of explosives are reviewed. Among the topics related to detonating explosives are: measurements of conductivity; enhancement of performance; and control of initiation and growth of reaction. Hayes...()^1 showed a strong correlation of peak electrical conductivity with carbon content of the detonation products. Ershov.......^2 linked detailed electrical conductivity measurements with reaction kinetics and this work was extended to enhance detonation performance electrically;...^3 for this, electrical power densities of the order of 100 TW/m^2 of explosive surface normal to the detonation front were required. However, small electrical powers are required to affect the initiation and growth of reaction.......^4,5 A continuation of this work will be reported. LA-UR 09-00873 .^1 B. Hayes, Procs. of 4th Symposium (International) on Detonation (1965), p. 595. ^2 A. Ershov, P. Zubkov, and L. Luk'yanchikov, Combustion, Explosion, and Shock Waves 10, 776-782 (1974). ^3 M. Cowperthwaite, Procs. 9th Detonation Symposium (1989), p. 388-395. ^4 M. A. Cook and T. Z. Gwyther, ``Influence of Electric Fields on Shock to Detonation Transition,'' (1965). ^5 D. Salisbury, R. Winter, and L. Biddle, Procs. of the APS Topical Conference on Shock Compression of Condensed Matter (2005) p. 1010-1013.

  10. Electromagnetic fields on a quantum scale. I.

    Science.gov (United States)

    Grimes, Dale M; Grimes, Craig A

    2002-10-01

    This is the first in a series of two articles, the second of which provides an exact electro-magnetic field description of photon emission, absorption, and radiation pattern. Photon energy exchanges are analyzed and shown to be the triggered, regenerative response of a non-local eigenstate electron. This first article presents a model-based, hidden variable analysis of quantum theory that provides the statistical nature of wave functions. The analysis uses the equations of classical electro-magnetism and conservation of energy while modeling an eigenstate electron as a nonlocal entity. Essential to the analysis are physical properties that were discovered and analyzed only after the historical interpretation of quantum mechanics was established: electron non-locality and the standing electro-magnetic energy that accompanies and encompasses an active, electrically small volume. The standing energy produces a driving radiation reaction force that, under certain circumstances, is many orders of magnitude larger than currently accepted values. These properties provide a sufficient basis for the Schrödinger equation as a descriptor of non-relativistic eigenstate electrons in or near equilibrium. The uncertainty principle follows, as does the exclusion principle. The analysis leads to atomic stability and causality in the sense that the status of physical phenomena at any instant specifies the status an instant later.

  11. Electromagnetic energy harvester for harvesting acoustic energy

    Indian Academy of Sciences (India)

    Farid U Khan

    Acoustics; energy harvesting; electromagnetic; Helmholtz resonator; sound pressure level; suspended coil. ... WSNs, which are supposed to operate for longer period of time. However ... several ambient energies such as wind, thermal, vibration, and solar are ..... textile plants in Northern India with specific reference to noise.

  12. Electromagnetic fields in stratified media

    CERN Document Server

    Li, Kai

    2009-01-01

    Dealing with an important branch of electromagnetic theory with many useful applications in subsurface communication, radar, and geophysical prospecting and diagnostics, this book introduces electromagnetic theory and wave propagation in complex media.

  13. Electromagnetic fields in cased borehole

    International Nuclear Information System (INIS)

    Lee, Ki Ha; Kim, Hee Joon; Uchida, Toshihiro

    2001-01-01

    Borehole electromagnetic (EM) measurements, using fiberglass-cased boreholes, have proven useful in oil field reservoir characterization and process monitoring (Wilt et al., 1995). It has been presumed that these measurements would be impossible in steel-cased wells due to the very large EM attenuation and phase shifts. Recent laboratory and field studies have indicated that detection of EM signals through steel casing should be possible at low frequencies, and that these data provide a reasonable conductivity image at a useful scale. Thus, we see an increased application of this technique to mature oilfields, and an immediate extension to geothermal industry as well. Along with the field experiments numerical model studies have been carried out for analyzing the effect of steel casing to the EM fields. The model used to be an infinitely long uniform casing embedded in a homogeneous whole space. Nevertheless, the results indicated that the formation signal could be accurately recovered if the casing characteristics were independently known (Becker et al., 1998; Lee el al., 1998). Real steel-cased wells are much more complex than the simple laboratory models used in work to date. The purpose of this study is to develop efficient numerical methods for analyzing EM fields in realistic settings, and to evaluate the potential application of EM technologies to cross-borehole and single-hole environment for reservoir characterization and monitoring

  14. High range electromagnetic fields. Experimental investigations

    International Nuclear Information System (INIS)

    Comino, E.; Boccardo, D.; Quaglino, A.

    2001-01-01

    It has been often discussed on the health effects from the electromagnetic fields, and nowadays this theme is particularly controlled and studied by the research-workers. It needs to know what is the risk connected to the exposure to the electromagnetism during a short or a long quantity of time and what are the health pathologies caused by the continue exposure. On one hand the results from epidemiological research can not still define the effect of the dose, on the other hand the legislative frame is variously fragmented and based on cautious concepts. But in this work, under the collaboration of Energy Resources Laboratory in Lausanne and the Geo resources and Territory Department in Turin University, are presented the early results on the experiments got out on high frequency (950 MHZ) in order to give a contribution to the debate between the scientific community and the public opinion [it

  15. Biological effects of electromagnetic fields

    International Nuclear Information System (INIS)

    Gabriel, C.

    1996-01-01

    The effects of electromagnetic (em) fields on biological systems were first observed and exploited well over a century ago. Concern over the possible health hazards of human exposure to such fields developed much later. It is now well known that excessive exposure to em fields may have in undesirable biological consequences. Standards were introduced to determine what constitute an excessive exposure and how to avoid it. Current concern over the issue of hazards stems mainly from recent epidemiological studies of exposed populations and also from the results of laboratory experiments in which whole animals are exposed in vivo or tissue and cell cultures exposed in vitro to low levels of irradiation. The underlying fear is the possibility of a causal relationship between chronic exposure to low field levels and some forms of cancer. So far the evidence does not add up to a firm statement on the matter. At present it is not known how and at what level, if at all, can these exposure be harmful to human health. This state of affair does not provide a basis for incorporating the outcome of such research in exposure standards. This paper will give a brief overview of the research in this field and how it is evaluated for the purpose of producing scientifically based standards. The emphasis will be on the physical, biophysical and biological mechanisms implicated in the interaction between em fields and biological systems. Understanding such mechanisms leads not only to a more accurate evaluation of their health implications but also to their optimal utilization, under controlled conditions, in biomedical applications. (author)

  16. On quantization of the electromagnetic field in radiation gauge

    International Nuclear Information System (INIS)

    Burzynski, A.

    1982-01-01

    This paper contains a detailed description of quantization of the electromagnetic field (in radiation gauge) and quantization of some basic physical variables connected with radiation field as energy, momentum and spin. The dynamics of the free quantum radiation field and the field interacting with external classical sources is described. The canonical formalism is not used explicity. (author)

  17. Medical applications of electromagnetic fields

    Science.gov (United States)

    Lai, Henry C.; Singh, Narendra P.

    2010-04-01

    In this article, we describe two possible applications of low-intensity non-ionizing electromagnetic fields (EMF) for the treatment of malaria and cancer, respectively. In malaria treatment, a low-intensity extremely-low frequency magnetic field can be used to induce vibration of hemozoin, a super-paramagnetic polymer particle, inside malaria parasites. This disturbance could cause free radical and mechanical damages leading to the death of the parasite. This concept has been tested in vitro on malaria parasites and found to be effective. This may provide a low cost effective treatment for malaria infection in humans. The rationale for cancer treatment using low-intensity EMF is based on two concepts that have been well established in the literature: (1) low-intensity non-thermal EMF enhances cytotoxic free radicals via the iron-mediated Fenton reaction; and (2) cancer cells have higher amounts of free iron, thus are more susceptible to the cytotoxic effects of EMF. Since normal cells contain minimal amount of free iron, the effect would be selectively targeting cancer cells. Thus, no adverse side effect would be expected as in traditional chemotherapy and radiation therapy. This concept has also been tested on human cancer cell and normal cells in vitro and proved to be feasible.

  18. Medical applications of electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Henry C; Singh, Narendra P, E-mail: hlai@u.washington.ed [Department of Bioengineering, University of Washington, Seattle, WA 98195-5061 (United States)

    2010-04-15

    In this article, we describe two possible applications of low-intensity non-ionizing electromagnetic fields (EMF) for the treatment of malaria and cancer, respectively. In malaria treatment, a low-intensity extremely-low frequency magnetic field can be used to induce vibration of hemozoin, a super-paramagnetic polymer particle, inside malaria parasites. This disturbance could cause free radical and mechanical damages leading to the death of the parasite. This concept has been tested in vitro on malaria parasites and found to be effective. This may provide a low cost effective treatment for malaria infection in humans. The rationale for cancer treatment using low-intensity EMF is based on two concepts that have been well established in the literature: (1) low-intensity non-thermal EMF enhances cytotoxic free radicals via the iron-mediated Fenton reaction; and (2) cancer cells have higher amounts of free iron, thus are more susceptible to the cytotoxic effects of EMF. Since normal cells contain minimal amount of free iron, the effect would be selectively targeting cancer cells. Thus, no adverse side effect would be expected as in traditional chemotherapy and radiation therapy. This concept has also been tested on human cancer cell and normal cells in vitro and proved to be feasible.

  19. Medical applications of electromagnetic fields

    International Nuclear Information System (INIS)

    Lai, Henry C; Singh, Narendra P

    2010-01-01

    In this article, we describe two possible applications of low-intensity non-ionizing electromagnetic fields (EMF) for the treatment of malaria and cancer, respectively. In malaria treatment, a low-intensity extremely-low frequency magnetic field can be used to induce vibration of hemozoin, a super-paramagnetic polymer particle, inside malaria parasites. This disturbance could cause free radical and mechanical damages leading to the death of the parasite. This concept has been tested in vitro on malaria parasites and found to be effective. This may provide a low cost effective treatment for malaria infection in humans. The rationale for cancer treatment using low-intensity EMF is based on two concepts that have been well established in the literature: (1) low-intensity non-thermal EMF enhances cytotoxic free radicals via the iron-mediated Fenton reaction; and (2) cancer cells have higher amounts of free iron, thus are more susceptible to the cytotoxic effects of EMF. Since normal cells contain minimal amount of free iron, the effect would be selectively targeting cancer cells. Thus, no adverse side effect would be expected as in traditional chemotherapy and radiation therapy. This concept has also been tested on human cancer cell and normal cells in vitro and proved to be feasible.

  20. The effect of gravitational wave on electromagnetic field and the possibility about electromagnetic detection of gravitational wave

    International Nuclear Information System (INIS)

    Tao Fuzhen; He Zhiqiang

    1983-01-01

    If the effect of gravitational wave on electromagnetic fields is used, and the gravitational wave is detected through the changes in electromagnetic fields, one can expect that the difficulty about the weakness of the signal of mechanical receiver can be avoided. Because of the effect of gravitational wave, the electromagnetic field emits energy, therefore, the energy which is detected will be higher than that by the mechanical receiver. The authors consider the Maxwell equations on the curved spacetime. They give solutions when the detecting fields are a free electromagnetic wave, standing wave and a constant field. (Auth.)

  1. Self field electromagnetism and quantum phenomena

    Science.gov (United States)

    Schatten, Kenneth H.

    1994-07-01

    Quantum Electrodynamics (QED) has been extremely successful inits predictive capability for atomic phenomena. Thus the greatest hope for any alternative view is solely to mimic the predictive capability of quantum mechanics (QM), and perhaps its usefulness will lie in gaining a better understanding of microscopic phenomena. Many ?paradoxes? and problematic situations emerge in QED. To combat the QED problems, the field of Stochastics Electrodynamics (SE) emerged, wherein a random ?zero point radiation? is assumed to fill all of space in an attmept to explain quantum phenomena, without some of the paradoxical concerns. SE, however, has greater failings. One is that the electromagnetic field energy must be infinit eto work. We have examined a deterministic side branch of SE, ?self field? electrodynamics, which may overcome the probelms of SE. Self field electrodynamics (SFE) utilizes the chaotic nature of electromagnetic emissions, as charges lose energy near atomic dimensions, to try to understand and mimic quantum phenomena. These fields and charges can ?interact with themselves? in a non-linear fashion, and may thereby explain many quantum phenomena from a semi-classical viewpoint. Referred to as self fields, they have gone by other names in the literature: ?evanesccent radiation?, ?virtual photons?, and ?vacuum fluctuations?. Using self fields, we discuss the uncertainty principles, the Casimir effects, and the black-body radiation spectrum, diffraction and interference effects, Schrodinger's equation, Planck's constant, and the nature of the electron and how they might be understood in the present framework. No new theory could ever replace QED. The self field view (if correct) would, at best, only serve to provide some understanding of the processes by which strange quantum phenomena occur at the atomic level. We discuss possible areas where experiments might be employed to test SFE, and areas where future work may lie.

  2. Genetic effects of nonionizing electromagnetic fields

    International Nuclear Information System (INIS)

    Lai, Henry

    2001-01-01

    Due to the increased use of electricity and wireless communication devices, there is a concern on whether exposure to nonionizing electromagnetic fields (50/60 Hz fields and radiofrequency radiation) can lead to harmful health effects, particularly, genetic effects and cancer development. This presentation will review recent research on genetic effects of power line frequency and radiofrequency electromagnetic fields. Even though the mechanism of interaction is still unknown, there is increasing evidence that these electromagnetic fields at low intensities can cause genetic damage in cells. There is also evidence suggesting that the effects are caused by oxidative stress. (author)

  3. Interactions between electromagnetic fields and matter

    CERN Document Server

    Steiner, Karl-Heinz

    2013-01-01

    Interactions between Electromagnetic Fields and Matter deals with the principles and methods that can amplify electromagnetic fields from very low levels of signals. This book discusses how electromagnetic fields can be produced, amplified, modulated, or rectified from very low levels to enable these for application in communication systems. This text also describes the properties of matter and some phenomenological considerations to the reactions of matter when an action of external fields results in a polarization of the particle system and changes the bonding forces existing in the matter.

  4. Electromagnetic processes in strong crystalline fields

    CERN Multimedia

    2007-01-01

    We propose a number of new investigations on aspects of radiation from high energy electron and positron beams (10-300 GeV) in single crystals and amorphous targets. The common heading is radiation emission by electrons and positrons in strong electromagnetic fields, but as the setup is quite versatile, other related phenomena in radiation emission can be studied as well. The intent is to clarify the role of a number of important aspects of radiation in strong fields as e.g. observed in crystals. We propose to measure trident 'Klein-like' production in strong crystalline fields, 'crystalline undulator' radiation, 'sandwich' target phenomena, LPM suppression of pair production as well as axial and planar effects in contributions of spin to the radiation.

  5. Dielectric Sensors Based on Electromagnetic Energy Tunneling

    Science.gov (United States)

    Siddiqui, Omar; Kashanianfard, Mani; Ramahi, Omar

    2015-01-01

    We show that metallic wires embedded in narrow waveguide bends and channels demonstrate resonance behavior at specific frequencies. The electromagnetic energy at these resonances tunnels through the narrow waveguide channels with almost no propagation losses. Under the tunneling behavior, high-intensity electromagnetic fields are produced in the vicinity of the metallic wires. These intense field resonances can be exploited to build highly sensitive dielectric sensors. The sensor operation is explained with the help of full-wave simulations. A practical setup consisting of a 3D waveguide bend is presented to experimentally observe the tunneling phenomenon. The tunneling frequency is predicted by determining the input impedance minima through a variational formula based on the Green function of a probe-excited parallel plate waveguide. PMID:25835188

  6. Dielectric Sensors Based on Electromagnetic Energy Tunneling

    Directory of Open Access Journals (Sweden)

    Omar Siddiqui

    2015-03-01

    Full Text Available We show that metallic wires embedded in narrow waveguide bends and channels demonstrate resonance behavior at specific frequencies. The electromagnetic energy at these resonances tunnels through the narrow waveguide channels with almost no propagation losses. Under the tunneling behavior, high-intensity electromagnetic fields are produced in the vicinity of the metallic wires. These intense field resonances can be exploited to build highly sensitive dielectric sensors. The sensor operation is explained with the help of full-wave simulations. A practical setup consisting of a 3D waveguide bend is presented to experimentally observe the tunneling phenomenon. The tunneling frequency is predicted by determining the input impedance minima through a variational formula based on the Green function of a probe-excited parallel plate waveguide.

  7. Subwavelength resonant antennas enhancing electromagnetic energy harvesting

    Science.gov (United States)

    Oumbe Tekam, Gabin; Ginis, Vincent; Seetharamdoo, Divitha; Danckaert, Jan

    2016-04-01

    In this work, an electromagnetic energy harvester operating at microwave frequencies is designed based on a cut- wire metasurface. This metamaterial is known to contain a quasistatic electric dipole resonator leading to a strong resonant electric response when illuminated by electromagnetic fields.1 Starting from an equivalent electrical circuit, we analytically design the parameters of the system to tune the resonance frequency of the harvester at the desired frequency band. Subsequently, we compare these results with numerical simulations, which have been obtained using finite elements numerical simulations. Finally, we optimize the design by investigating the best arrangement for energy harvesting by coupling in parallel and in series many single layers of cut-wire metasurfaces. We also discuss the implementation of different geometries and sizes of the cut-wire metasurface for achieving different center frequencies and bandwidths.

  8. Electromagnetic-gravitational conversion cross sections in external electromagnetic fields

    International Nuclear Information System (INIS)

    Hoang Ngoc Long; Dang Van Soa; Tuan Tran, A.

    1994-09-01

    The classical processes: the conversion of photons into gravitons in the static electromagnetic fields are considered by using Feynman perturbation techniques. The differential cross sections are presented for the conversion in the electric field of the flat condenser and the magnetic field of the solenoid. A numerical evaluation shows that the cross sections may have the observable value in the present technical scenario. (author). 11 refs

  9. Nanomechanical electric and electromagnetic field sensor

    Science.gov (United States)

    Datskos, Panagiotis George; Lavrik, Nickolay

    2015-03-24

    The present invention provides a system for detecting and analyzing at least one of an electric field and an electromagnetic field. The system includes a micro/nanomechanical oscillator which oscillates in the presence of at least one of the electric field and the electromagnetic field. The micro/nanomechanical oscillator includes a dense array of cantilevers mounted to a substrate. A charge localized on a tip of each cantilever interacts with and oscillates in the presence of the electric and/or electromagnetic field. The system further includes a subsystem for recording the movement of the cantilever to extract information from the electric and/or electromagnetic field. The system further includes a means of adjusting a stiffness of the cantilever to heterodyne tune an operating frequency of the system over a frequency range.

  10. Biological effects of electromagnetic fields

    African Journals Online (AJOL)

    2012-02-28

    Feb 28, 2012 ... radiofrequency emitting sources are radars, mobile phones and their base stations, ... and industrial applications, could have effect on living organisms. ...... Hazards of Electromagnetic Pollution (Msc Thesis). Department of ...

  11. Thermodynamic properties of open noncritical string in external electromagnetic field

    International Nuclear Information System (INIS)

    Lichtzier, I.M.; Odintsov, S.D.; Bytsenko, A.A.

    1991-01-01

    We investigate the thermodynamics of open noncritical string (charged and neutral) in an external constant magnetic field. The free energy and Hagedorn temperature are calculated. It is shown that Hagedorn temperature is the same as in the absence of constant magnetic field. We present also the expressions for the free energy and Hagedorn temperature of the neutral open noncritical string in an external constant electromagnetic field. In this case Hagedorn temperature depends on the external electric field. (author)

  12. Electromagnetic Field Theory A Collection of Problems

    CERN Document Server

    Mrozynski, Gerd

    2013-01-01

    After a brief introduction into the theory of electromagnetic fields and the definition of the field quantities the book teaches the analytical solution methods of Maxwell’s equations by means of several characteristic examples. The focus is on static and stationary electric and magnetic fields, quasi stationary fields, and electromagnetic waves. For a deeper understanding, the many depicted field patterns are very helpful. The book offers a collection of problems and solutions which enable the reader to understand and to apply Maxwell’s theory for a broad class of problems including classical static problems right up to waveguide eigenvalue problems. Content Maxwell’s Equations - Electrostatic Fields - Stationary Current Distributions – Magnetic Field of Stationary Currents – Quasi Stationary Fields: Eddy Currents - Electromagnetic Waves Target Groups Advanced Graduate Students in Electrical Engineering, Physics, and related Courses Engineers and Physicists Authors Professor Dr.-Ing. Gerd Mrozynski...

  13. Electromagnetic fields: the new European directive

    International Nuclear Information System (INIS)

    Moureaux, Patrick

    2014-01-01

    A European directive is specifying the thresholds for exposure to electromagnetic fields. The risk assessment approach proposed should enable worker health to be taken better into account. An overview of the new provisions. (author)

  14. Electromagnetic field computation by network methods

    CERN Document Server

    Felsen, Leopold B; Russer, Peter

    2009-01-01

    This monograph proposes a systematic and rigorous treatment of electromagnetic field representations in complex structures. The book presents new strong models by combining important computational methods. This is the last book of the late Leopold Felsen.

  15. Open bosonic string in background electromagnetic field

    International Nuclear Information System (INIS)

    Nesterenko, V.V.

    1987-01-01

    The classical and quantum dynamics of an open string propagating in the D-dimensional space-time in the presence of a background electromagnetic field is investigated. An important point in this consideration is the use of the generalized light-like gauge. There are considered the strings of two types; the neutral strings with charges at their ends obeying the condition q 1 +q 2 =0 and the charged strings having a net charge q 1 +q 2 ≠ 0. The consistency of theory demands that the background electric field does not exceed its critical value. The distance between the mass levels of the neutral open string decreases (1-e 2 ) times in comparison with the free string, where e is the dimensionless strength of the electric field. The magnetic field does not affect this distance. It is shown that at a classical level the squared mass of the neutral open string has a tachyonic contribution due to the motion of the string as a whole in transverse directions. The tachyonic term disappears if one considers, instead of M 2 , the string energy in a special reference frame where the projection of the total canonical momentum of the string onto the electric field vanishes. The contributions due to zero point fluctuations to the energy spectrum of the neutral string and to the Virasoro operators in the theory of charged string are found

  16. Narrow field electromagnetic sensor system and method

    International Nuclear Information System (INIS)

    McEwan, T.E.

    1996-01-01

    A narrow field electromagnetic sensor system and method of sensing a characteristic of an object provide the capability to realize a characteristic of an object such as density, thickness, or presence, for any desired coordinate position on the object. One application is imaging. The sensor can also be used as an obstruction detector or an electronic trip wire with a narrow field without the disadvantages of impaired performance when exposed to dirt, snow, rain, or sunlight. The sensor employs a transmitter for transmitting a sequence of electromagnetic signals in response to a transmit timing signal, a receiver for sampling only the initial direct RF path of the electromagnetic signal while excluding all other electromagnetic signals in response to a receive timing signal, and a signal processor for processing the sampled direct RF path electromagnetic signal and providing an indication of the characteristic of an object. Usually, the electromagnetic signal is a short RF burst and the obstruction must provide a substantially complete eclipse of the direct RF path. By employing time-of-flight techniques, a timing circuit controls the receiver to sample only the initial direct RF path of the electromagnetic signal while not sampling indirect path electromagnetic signals. The sensor system also incorporates circuitry for ultra-wideband spread spectrum operation that reduces interference to and from other RF services while allowing co-location of multiple electronic sensors without the need for frequency assignments. 12 figs

  17. Wireless data transmission from inside electromagnetic fields.

    Science.gov (United States)

    Huertas, José Ignacio; Barraza, Roberto; Echeverry, Julian Mauricio

    2010-01-01

    This paper describes analytical and experimental work developed to evaluate the effects of the electromagnetic fields produced by high-voltage lines (400 kV) on wireless data transmission at the 900MHz band. In this work the source of the data transmission is located inside the electromagnetic field and the reception station is located at different distances from the power lines. Different atmospheric conditions are considered.

  18. Electromagnetic wave energy conversion research

    Science.gov (United States)

    Bailey, R. L.; Callahan, P. S.

    1975-01-01

    Known electromagnetic wave absorbing structures found in nature were first studied for clues of how one might later design large area man-made radiant-electric converters. This led to the study of the electro-optics of insect dielectric antennae. Insights were achieved into how these antennae probably operate in the infrared 7-14um range. EWEC theoretical models and relevant cases were concisely formulated and justified for metal and dielectric absorber materials. Finding the electromagnetic field solutions to these models is a problem not yet solved. A rough estimate of losses in metal, solid dielectric, and hollow dielectric waveguides indicates future radiant-electric EWEC research should aim toward dielectric materials for maximum conversion efficiency. It was also found that the absorber bandwidth is a theoretical limitation on radiant-electric conversion efficiency. Ideally, the absorbers' wavelength would be centered on the irradiating spectrum and have the same bandwith as the irradiating wave. The EWEC concept appears to have a valid scientific basis, but considerable more research is needed before it is thoroughly understood, especially for the complex randomly polarized, wide band, phase incoherent spectrum of the sun. Specific recommended research areas are identified.

  19. The response of nuclei to electromagnetic fields

    International Nuclear Information System (INIS)

    Bernstein, A.M.

    1987-01-01

    The purpose of these lectures is to give a general introduction to intermediate energy electromagnetic physics at the graduate student level. The aim is to convey physical insight, to attempt to explain the motivation for the measurements, what the results are, what has been understood, and what puzzles remain for the future. The author hopes to give a panorama and to convey the present sense of excitement in this very active and developing field. The topics which are treated include: elastic and quasi-elastic electron scattering, electro excitation of the Δ in nuclei, (γ,π) reactions and a brief introduction to hypernuclear production by the (γ,Κ/sup +/) reaction. Time doses not allow the coverage of many important topics such as coincidence reactions, polarization phenomena, and inelastic scattering to discrete nuclear states

  20. INVESTIGATION OF ELECTROMAGNETIC FIELDS IN RESIDENTIAL AREAS

    Directory of Open Access Journals (Sweden)

    Dušan MEDVEĎ

    2017-09-01

    Full Text Available This article is devoted to investigation of impact of electromagnetic fields around the electrical equipment used in a residential area and their impact on the human body. This paper was based on sets of measurements of magnetic induction B with magnetometer and on computational simulations in ANSYS for particular appliances often used in household. The results from measurements and simulations led to setting out the recommendations for practical action in the form of elimination of harmful electromagnetic radiation.

  1. Electromagnetic energy and food processing

    International Nuclear Information System (INIS)

    Mudgett, R.

    1988-01-01

    The use of electromagnetic energy in food processing is reviewed with respect to food safety, nutritional quality, and organoleptic quality. The effects of nonionizing radiation sources such as microwave and radio-frequency energy and ionizing radiation sources, e.g. radioactive cobalt-60 and caesium-137, on the inactivation of microbes and nutrients are compared with those of conventional heating processes both in terms of their kinetic behavior and their mechanisms of interaction with foods. The kinetics of microwave and conventional thermal inactivation are considered for a generalized nth-order model based on time and temperature conditions. However, thermal inactivation effects are often modeled by 1 st-order kinetics. Microbial and nutrient inactivation by ionizing sources are considered for a 1 st-order model based on radiation dose. Both thermal and radiation resistance concepts are reviewed and some typical values of radiation resistance are given for sensitive vegetative bacterial cells, yeasts, and molds and for resistant bacterial spores and viruses. Nonionizing microwave energy sources are increasingly used in home and industrial food processing and are well-accepted by the American public. But, despite recent Food and Drug Administration approval of low and intermediate ionizing radiation dose levels for grains and other plant products and the fact that irradiated foods are sold in more than 20 countries of the world, public fears in the U.S. about nuclear energy may limit the role of ionizing radiation in food processing and preservation and may also limit the use of nuclear fuels as an alternate source of electrical energy. (33 refs.)

  2. Nonlinear properties of gated graphene in a strong electromagnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Avetisyan, A. A., E-mail: artakav@ysu.am; Djotyan, A. P., E-mail: adjotyan@ysu.am [Yerevan State University, Department of Physics (Armenia); Moulopoulos, K., E-mail: cos@ucy.ac.cy [University of Cyprus, Department of Physics (Cyprus)

    2017-03-15

    We develop a microscopic theory of a strong electromagnetic field interaction with gated bilayer graphene. Quantum kinetic equations for density matrix are obtained using a tight binding approach within second quantized Hamiltonian in an intense laser field. We show that adiabatically changing the gate potentials with time may produce (at resonant photon energy) a full inversion of the electron population with high density between valence and conduction bands. In the linear regime, excitonic absorption of an electromagnetic radiation in a graphene monolayer with opened energy gap is also studied.

  3. Scalar, electromagnetic, and gravitational fields interaction: Particlelike solutions

    International Nuclear Information System (INIS)

    Bronnikov, K.A.; Melnikov, V.N.; Shikin, G.N.; Staniukovich, K.P.

    1979-01-01

    Particlelike static spherically symmetric solutions to massless scalar and electromagnetic field equations combined with gravitational field equations are considered. Two criteria for particlelike solutions are formulated: the strong one (solutions are required to be singularity free) and the weak one (singularities are admitted but the total energy and material field energy should be finite). Exact solutions for the following physical systems are considered with their own gravitational field: (i) linear scalar (minimally coupled or conformal) plus electromagnetic field; (ii) the same fields with a bare mass source in the form of charged incoherent matter distributions; (iii) nonlinear electromagnetic field with an abritrary dependence on the invariant F/sub alphabeta/F/sup alphabeta/; and (iv) directly interacting scalar and electromagnetic fields. Case (i) solutions are not particlelike (except those with horizons, in which static regions formally satisfy the weak criterion). For systems (ii), examples of nonsingular models are constructed, in particular, a model for a particle--antiparticle pair of a Wheeler-handle type, without scalar field and explict electric charges. Besides, a number of limitations upon nonsingular model parameters is indicated. Systems (iii) are proved to violate the strong criterion for any type of nonlinearity but can satisfy the weak criterion (e.g., the Born--Infeld nonlinearity). For systems (iv) some particlelike solutions by the weak criterion are constructed and a regularizing role of gravitation is demonstrated. Finally, an example of a field system satisfying the strong criterion is given

  4. Electromagnetic fields of Nanometer electromagnetic waves and X-ray. New frontiers of electromagnetic wave engineering

    International Nuclear Information System (INIS)

    2009-01-01

    The investigating committee aimed at research on electromagnetic fields in functional devices and X-ray fibers for efficient coherent X-ray generation and their material science, high-precision manufacturing, X-ray microscope, application to medical and information communication technologies, such as interaction between material and nanometer electromagnetic waves of radiated light and X-ray, interaction between microwaves and particle beams, theory and design of high-frequency waveguides for resonator and accelerator, from January 2003 to December 2005. In this report, we describe our research results, in particular, on the topics of synchrotron radiation and Cherenkov radiation, Kyushu synchrotron light source and its technology, nanometer electromagnetic fields in optical region, process of interaction between evanescent waves and near-field light, orthogonal relation of electromagnetic fields including evanescent waves in dispersive dielectrics, optical amplification using electron beam, nanometer electromagnetic fields in focusing waveguide lens device with curved facets, electromagnetic fields in nanometer photonic crystal waveguide consisting of atoms, X-ray scattering and absorption I bio-material for image diagnosis. (author)

  5. Electromagnetic fields in fractal continua

    Energy Technology Data Exchange (ETDEWEB)

    Balankin, Alexander S., E-mail: abalankin@ipn.mx [Grupo “Mecánica Fractal”, Instituto Politécnico Nacional, México D.F., 07738 Mexico (Mexico); Mena, Baltasar [Instituto de Ingeniería, Universidad Nacional Autónoma de México, México D.F. (Mexico); Patiño, Julián [Grupo “Mecánica Fractal”, Instituto Politécnico Nacional, México D.F., 07738 Mexico (Mexico); Morales, Daniel [Instituto Mexicano del Petróleo, México D.F., 07730 Mexico (Mexico)

    2013-04-01

    Fractal continuum electrodynamics is developed on the basis of a model of three-dimensional continuum Φ{sub D}{sup 3}⊂E{sup 3} with a fractal metric. The generalized forms of Maxwell equations are derived employing the local fractional vector calculus related to the Hausdorff derivative. The difference between the fractal continuum electrodynamics based on the fractal metric of continua with Euclidean topology and the electrodynamics in fractional space F{sup α} accounting the fractal topology of continuum with the Euclidean metric is outlined. Some electromagnetic phenomena in fractal media associated with their fractal time and space metrics are discussed.

  6. A class of non-null toroidal electromagnetic fields and its relation to the model of electromagnetic knots

    International Nuclear Information System (INIS)

    Arrayás, Manuel; Trueba, José L

    2015-01-01

    An electromagnetic knot is an electromagnetic field in vacuum in which the magnetic lines and the electric lines coincide with the level curves of a pair of complex scalar fields ϕ and θ (see equations (A.1), (A.2)). When electromagnetism is expressed in terms of electromagnetic knots, it includes mechanisms for the topological quantization of the electromagnetic helicity, the electric charge, the electromagnetic energy inside a cavity and the magnetic flux through a superconducting ring. In the case of electromagnetic helicity, its topological quantization depends on the linking number of the field lines, both electric and magnetic. Consequently, to find solutions of the electromagnetic knot equations with nontrivial topology of the field lines has important physical consequences. We study a new class of solutions of Maxwell's equations in vacuum Arrayás and Trueba (2011 arXiv:1106.1122) obtained from complex scalar fields that can be interpreted as maps S 3 →S 2 , in which the topology of the field lines is that of the whole torus-knot set. Thus this class of solutions is built as electromagnetic knots at initial time. We study some properties of those fields and consider if detection based on the energy and momentum observables is possible. (paper)

  7. Magnetic fields, special relativity and potential theory elementary electromagnetic theory

    CERN Document Server

    Chirgwin, B H; Kilmister, C W

    1972-01-01

    Magnetic Fields, Special Relativity and Potential Theory is an introduction to electromagnetism, special relativity, and potential theory, with emphasis on the magnetic field of steady currents (magnetostatics). Topics covered range from the origin of the magnetic field and the magnetostatic scalar potential to magnetization, electromagnetic induction and magnetic energy, and the displacement current and Maxwell's equations. This volume is comprised of five chapters and begins with an overview of magnetostatics, followed by a chapter on the methods of solving potential problems drawn from elec

  8. Quantum processes in an intense electromagnetic field

    International Nuclear Information System (INIS)

    Gitman, D.M.

    1976-01-01

    An approach is proposed to the consideration of processes in an external electromagnetic field which produces real pairs. Interaction with the field is taken into account precisely with the aid of solutions of the Dirac's equation. Processes of arbitrary order with respect to electron-photon interaction are considered

  9. Charged particles in external electromagnetic fields

    International Nuclear Information System (INIS)

    Giovannini, N.P.D.

    1976-01-01

    The present study contains a general theoretical group analysis of the problem of a charged massive particle moving in an (arbitrary) classical external electromagnetic field. This analysis is essentially based on the space-time symmetry properties of e.m. fields and e.m. field equations, as well as the fact that the considered equations of motion depend on the field via a potential

  10. Differential form representation of stochastic electromagnetic fields

    Directory of Open Access Journals (Sweden)

    M. Haider

    2017-09-01

    Full Text Available In this work, we revisit the theory of stochastic electromagnetic fields using exterior differential forms. We present a short overview as well as a brief introduction to the application of differential forms in electromagnetic theory. Within the framework of exterior calculus we derive equations for the second order moments, describing stochastic electromagnetic fields. Since the resulting objects are continuous quantities in space, a discretization scheme based on the Method of Moments (MoM is introduced for numerical treatment. The MoM is applied in such a way, that the notation of exterior calculus is maintained while we still arrive at the same set of algebraic equations as obtained for the case of formulating the theory using the traditional notation of vector calculus. We conclude with an analytic calculation of the radiated electric field of two Hertzian dipole, excited by uncorrelated random currents.

  11. Differential form representation of stochastic electromagnetic fields

    Science.gov (United States)

    Haider, Michael; Russer, Johannes A.

    2017-09-01

    In this work, we revisit the theory of stochastic electromagnetic fields using exterior differential forms. We present a short overview as well as a brief introduction to the application of differential forms in electromagnetic theory. Within the framework of exterior calculus we derive equations for the second order moments, describing stochastic electromagnetic fields. Since the resulting objects are continuous quantities in space, a discretization scheme based on the Method of Moments (MoM) is introduced for numerical treatment. The MoM is applied in such a way, that the notation of exterior calculus is maintained while we still arrive at the same set of algebraic equations as obtained for the case of formulating the theory using the traditional notation of vector calculus. We conclude with an analytic calculation of the radiated electric field of two Hertzian dipole, excited by uncorrelated random currents.

  12. Atom collisions in a strong electromagnetic field

    International Nuclear Information System (INIS)

    Smirnov, V.S.; Chaplik, A.V.

    1976-01-01

    It is shown that the long-range part of interatomic interaction is considerably altered in a strong electromagnetic field. Instead of the van der Waals law the potential asymptote can best be described by a dipole-dipole R -3 law. Impact broadening and the line shift in a strong nonresonant field are calculated. The possibility of bound states of two atoms being formed in a strong light field is discussed

  13. Reasearch and Evaluation of Electromagnetic Fields of Refrigerators

    Directory of Open Access Journals (Sweden)

    Pranas Baltrėnas

    2013-12-01

    Full Text Available The use of refrigerators causes the occurence of electromagnetic fields that are invisible and intangible, which therefore makes difficulties in protecting ourselves from them. A refrigerator is an irreplaceable item in domestic household and thus can be hardly ignored by a modern way of human life. In order to preserve the characteristics of products, the refrigerator must operate continuously (24 hrs a day, regardless of the time of the year. This results in a huge increase in electricity consumption, which leads to energy consumption related pollution of the environment emitting CO2 gas. On these grounds, it is necessary to assess electromagnetic fields created by the refrigerator. Studies on electromagnetic fields produced by refrigerators were conducted in domestic premises where people spent a significant part of the day. For comparison purposes, five different power refrigerators were chosen (1 – 0.20 kW; 2 – 0.25 kW; 3 – 0.30 kW; 4 – 0.35 kW; 5 – 0.40 kW. The obtained results, according to the parameters of their electromagnetic fields, were presented in graphs and charts and showed that the values of electric and magnetic intensity of refrigerators depended on the distance and the power of the refrigerator. The conducted research also disclosed that none of tested refrigerators exceeded the permissible limits of electromagnetic fields.Article in Lithuanian

  14. Anisotropic Bianchi II cosmological models with matter and electromagnetic fields

    International Nuclear Information System (INIS)

    Soares, D.

    1978-01-01

    A class of solutions of Einstein-Maxwell equations is presented, which corresponds to anisotropic Bianchi II spatially homogeneous cosmological models with perfect fluid and electromagnetic field. A particular model is examined and shown to be unstable for perturbations of the electromagnetic field strength parameter about a particular value. This value defines a limiar unstable case in which the ratio epsilon, of the fluid density to the e.m. energy density is monotonically increasing with a minimum finite value at the singularity. Beyond this limiar, the model has a matter dominated singularity, and a characteristic stage appears where epsilon has a minimum, at a finite time from the singularity. For large times, the models tend to an exact solution for zero electromagnetic field and fluid with p = (1/5)p. Some cosmological features of the models are calculated, as the effect of anisotropy on matter density and expansion time scale factors, as compared to the corresponding Friedmann model [pt

  15. Assisted of electromagnetic fields in glucose production from cassava stems

    Science.gov (United States)

    Lismeri, Lia; Haryati, Sri; Djoni Bustan, M.; Darni, Yuli

    2018-03-01

    Decrease in fossil fuel reserves that led to high price has become major problem in many countries around the world. To acquire the sustainability of energy reserves, the renewable energies obtained from plant biomass will therefore have to play an increasing role in fulfilling energy demand throughout the century. Renewable energy source must be explored by innovative techniques which is safe to the environment and low in energy consumptions. This research conducted to produce glucose from cassava stems assisted by electromagnetic field inductions process. The parameters used in this research were pretreatment solvent, concentration, temperature and electrical currents. The electromagnetic field inductions could be applied to increase glucose productivity with the maximum yield of glucose was 47.43%.

  16. Health protection guidelines for electromagnetic field exposures

    International Nuclear Information System (INIS)

    Taki, Masao

    1999-01-01

    In order to protect human health from excessive exposure to electromagnetic fields safety guidelines have been established by national and international organizations. The International Commission on Nonionization Radiation Protection is one of these organizations, whose guidelines are briefly regarded as typical. The activities on this issue in various countries are reviewed. Recent situations and the problems still unsolved are also discussed. (author)

  17. Simple economical stabilizer for electromagnet field

    International Nuclear Information System (INIS)

    Vas'kov, O.S.; Domanevskij, D.S.; Zinkevich, Yu.V.; Soroka, E.V.; Shavel', N.N.

    1988-01-01

    Field stabilizer within high-power electromagnet gap at direct current up to 75 A and up to 100 V voltage in the winding is described. 15 parallel-connected KT 945A transistors, operation mode of which allows to do without radiators and forced cooling are used as controlling element of pulsed stabilizer

  18. Electromagnetic signatures of far-field gravitational radiation in the 1 + 3 approach

    International Nuclear Information System (INIS)

    Chua, Alvin J K; Cañizares, Priscilla; Gair, Jonathan R

    2015-01-01

    Gravitational waves (GWs) from astrophysical sources can interact with background electromagnetic fields, giving rise to distinctive and potentially detectable electromagnetic signatures. In this paper, we study such interactions for far-field gravitational radiation using the 1 + 3 approach to relativity. Linearized equations for the electromagnetic field on perturbed Minkowski space are derived and solved analytically. The inverse Gertsenshteĭn conversion of GWs in a static electromagnetic field is rederived, and the resultant electromagnetic radiation is shown to be significant for highly magnetized pulsars in compact binary systems. We also obtain a variety of nonlinear interference effects for interacting gravitational and electromagnetic waves, although wave–wave resonances previously described in the literature are absent when the electric–magnetic self-interaction is taken into account. The fluctuation and amplification of electromagnetic energy flux as the GW strength increases towards the gravitational–electromagnetic frequency ratio is a possible signature of gravitational radiation from extended astrophysical sources. (paper)

  19. At the heart of the waves - Electromagnetic fields in question

    International Nuclear Information System (INIS)

    Ndagijimana, Fabien; Gaudaire, Francois

    2013-01-01

    This document briefly presents a book in which the author describes what an electromagnetic wave is, the use of electromagnetic waves, how an information is transmitted by means of an electromagnetic wave, what wave modulation is, what multiplexing is, what the characteristics of an antenna are, how waves propagate, how electromagnetic shielding works, what the CEM (electromagnetic compatibility) is, and how a cellular phone network works, in the framework of electromagnetic fields risk assessment

  20. Electromagnetic fields in an expanding universe

    International Nuclear Information System (INIS)

    Hogan, P.A.; Ellis, G.F.R.

    1989-01-01

    The asymptotic form of the electromagnetic field due to a bounded distribution of charge current in an open, expanding Friedmann--Lemaitre--Robertson--Walker universe is studied. The technique used is to first describe a mechanism for passing from a solution of Maxwell's vacuum field equations on Minkowskian space-time to a solution of Maxwell's field equations in a region free of charge current on the cosmological background. This is tested on the field of an accelerating point charge and then applied to the rigorous treatment of the asymptotic electromagnetic field of a bounded charge-current distribution in Minkowskian space-time given by Goldberg and Kerr [J. Math. Phys. 5, 172 (1964)]. A ''peeling expansion'' of the electromagnetic field in the expanding universe is obtained in inverse powers of a parameter that is proportional to the area distance along the generators of future null cones with vertices on the world line of a fundamental observer. The algebraic character of the two leading coefficients in the expansion is the same as that of the two leading coefficients in the Goldberg--Kerr expansion in Minkowskian space-time. In addition, bounds can be calculated, at any instant in the history of a fundamental observer, on all the coefficients in the peeling expansion, as a consequence of the evaluation of such bounds by Goldberg and Kerr in the case treated by them

  1. The electromagnetic bio-field: clinical experiments and interferences.

    Science.gov (United States)

    Burnei, G; Hodorogea, D; Georgescu, I; Gavriliu, Ş; Drăghici, I; Dan, D; Vlad, C; Drăghici, L

    2012-06-12

    One of the most important factors is the technical and scientifically rapid development that is continually modifying the world we live in and polluting it with electromagnetic radiations. A functional and structural influence of magnetic and electromagnetic field on living organisms is presented in the literature by many performed experiments. The notion of bio-field represents the electromagnetic field generated by the bio-structures, not only in their normal physiological activities but also in their pathological states. There is a tight interdependency between the bio-field and the bio-structure, which respects the primary notion of an electromagnetic field given by the Maxwell-Faraday laws, in which, the electromagnetic phenomena are simplified to the field variations. These variations can be expressed in a coherent differential equation system that bounds the field vectors to different space points at different time moments. The living organisms cannot contain electrostatic and magneto-static fields due to the intense activity of the bio-structures. The biochemical reactions that have high rhythms and speeds always impose the electrodynamics character of the biologic field that also corresponds to the stability of the protein molecule that can be explained only through a dynamic way. The existent energy is not considered an exciting agent, and it does not lead to any effects. The parameters of these elementary bio-fields cannot yet be fully known due to technical reasons. The biological structures are very complex ones and undergo continuous dynamical activity. That is why the calculus model should be related to the constant dynamics, nowadays being very difficult to express.

  2. Electromagnetic fields - introduction to relevant issues

    International Nuclear Information System (INIS)

    Brueggemeyer, H.; Csicsaky, M.

    1993-01-01

    This introductory paper surveys potential sources of electric magnetic, and electro-magnetic fields. Various cases are discussed to exemplify the total frequency range: nuclear magnetic resonance tomography, high-voltage transmission lines, transformer stations, effect lighting balls, military transmitters, transmitter towers of the Postal Services and other operators, mobile radiotelephone equipment, large broadcasting transmitters, radar radiation, high-frequency heat therapy. There is evidence suggesting that electric, magnetic and electro-magnetic fields may possibly represent a certain nuisance or health hazard even at field strength occuring in equipment used for every-day-life purposes, with an emphasis on their possible actions and effects in children and adolescents. The author discusses, in conclusion, the aerial equipment ordinance issued by Lower Saxony. (Uhe) [de

  3. Radiofrequency Electromagnetic Field Map of Timisoara

    Science.gov (United States)

    Stefu, N.; Solyom, I.; Arama, A.

    2015-12-01

    There are many electromagnetic field (EMF) sources nowadays acting simultaneously, especially in urban areas, making the theoretical estimation of electromagnetic power at ground level very difficult. This paper reports on EMF maps built with measurements collected in Timisoara, at various radiofrequencies. A grid of 15×15 squares was built (approximate resolution 400m x 400m) and measurements of the average and maximum values of the electric field E, magnetic field H and total power density S at 0.9, 1.8 and 2.4 GHz were collected in every node of the grid. Positions of the nodes in terms of latitude and longitude were also collected. Maps were built presenting the spatial distribution of the measured quantities over Timisoara. Potential influences of EMF on public health are discussed.

  4. Ionization in a quantized electromagnetic field

    International Nuclear Information System (INIS)

    Gonoskov, I. A.; Vugalter, G. A.; Mironov, V. A.

    2007-01-01

    An analytical expression for a matrix element of the transition from a bound state of an electron in an atom to continuum states is obtained by solving the problem of interaction of the electron with a quantized electromagnetic field. This expression is used to derive formulas for the photoelectron spectrum and the rate of ionization of the simplest model atomic system upon absorption of an arbitrary number of photons. The expressions derived are analyzed and compared with the corresponding relationships obtained via other approaches. It is demonstrated that there are differences as compared to the case of the classical field. In particular, the photoelectron spectrum exhibits dips due to the destructive interference of the transition amplitudes in the quantized electromagnetic field

  5. PROBABILISTIC APPROACH OF STABILIZED ELECTROMAGNETIC FIELD EFFECTS

    Directory of Open Access Journals (Sweden)

    FELEA. I.

    2017-09-01

    Full Text Available The effects of the omnipresence of the electromagnetic field are certain and recognized. Assessing as accurately as possible these effects, which characterize random phenomena require the use of statistical-probabilistic calculation. This paper aims at assessing the probability of exceeding the admissible values of the characteristic sizes of the electromagnetic field - magnetic induction and electric field strength. The first part justifies the need for concern and specifies how to approach it. The mathematical model of approach and treatment is presented in the second part of the paper and the results obtained with reference to 14 power stations are synthesized in the third part. In the last part, are formulated the conclusions of the evaluations.

  6. Calibration and uncertainty in electromagnetic fields measuring methods

    International Nuclear Information System (INIS)

    Anglesio, L.; Crotti, G.; Borsero, M.; Vizio, G.

    1999-01-01

    Calibration and reliability in electromagnetic field measuring methods are assured by calibration of measuring instruments. In this work are illustrated systems for generation of electromagnetic fields at low and high frequency, calibration standard and accuracy [it

  7. Topology optimization of nanoparticles for localized electromagnetic field enhancement

    DEFF Research Database (Denmark)

    Christiansen, Rasmus Ellebæk; Vester-Petersen, Joakim; Madsen, Søren Peder

    2017-01-01

    We consider the design of individual and periodic arrangements of metal or semiconductor nanoparticles for localized electromagnetic field enhancement utilizing a topology optimization based numerical framework as the design tool. We aim at maximizing a function of the electromagnetic field...

  8. Understanding possible electromagnetic counterparts to loud gravitational wave events: Binary black hole effects on electromagnetic fields

    International Nuclear Information System (INIS)

    Palenzuela, Carlos; Lehner, Luis; Yoshida, Shin

    2010-01-01

    In addition to producing loud gravitational waves, the dynamics of a binary black hole system could induce emission of electromagnetic radiation by affecting the behavior of plasmas and electromagnetic fields in their vicinity. We study how the electromagnetic fields are affected by a pair of orbiting black holes through the merger. In particular, we show how the binary's dynamics induce a variability in possible electromagnetically induced emissions as well as an enhancement of electromagnetic fields during the late-merge and merger epochs. These time dependent features will likely leave their imprint in processes generating detectable emissions and can be exploited in the detection of electromagnetic counterparts of gravitational waves.

  9. Electromagnetic field induced biological effects in humans.

    Science.gov (United States)

    Kaszuba-Zwoińska, Jolanta; Gremba, Jerzy; Gałdzińska-Calik, Barbara; Wójcik-Piotrowicz, Karolina; Thor, Piotr J

    2015-01-01

    Exposure to artificial radio frequency electromagnetic fields (EMFs) has increased significantly in recent decades. Therefore, there is a growing scientific and social interest in its influence on health, even upon exposure significantly below the applicable standards. The intensity of electromagnetic radiation in human environment is increasing and currently reaches astronomical levels that had never before experienced on our planet. The most influential process of EMF impact on living organisms, is its direct tissue penetration. The current established standards of exposure to EMFs in Poland and in the rest of the world are based on the thermal effect. It is well known that weak EMF could cause all sorts of dramatic non-thermal effects in body cells, tissues and organs. The observed symptoms are hardly to assign to other environmental factors occurring simultaneously in the human environment. Although, there are still ongoing discussions on non-thermal effects of EMF influence, on May 31, 2011--International Agency for Research on Cancer (IARC)--Agenda of World Health Organization (WHO) has classified radio electromagnetic fields, to a category 2B as potentially carcinogenic. Electromagnetic fields can be dangerous not only because of the risk of cancer, but also other health problems, including electromagnetic hypersensitivity (EHS). Electromagnetic hypersensitivity (EHS) is a phenomenon characterized by the appearance of symptoms after exposure of people to electromagnetic fields, generated by EHS is characterized as a syndrome with a broad spectrum of non-specific multiple organ symptoms including both acute and chronic inflammatory processes located mainly in the skin and nervous systems, as well as in respiratory, cardiovascular systems, and musculoskeletal system. WHO does not consider the EHS as a disease-- defined on the basis of medical diagnosis and symptoms associated with any known syndrome. The symptoms may be associated with a single source of EMF

  10. Effect of electromagnetic fields on the bacteria bioluminescent activity

    International Nuclear Information System (INIS)

    Berzhanskaya, L.Yu.; Berzhanskij, V.N.; Beloplotova, O.Yu.

    1995-01-01

    The effect of electromagnetic field with frequency from 36.2 to 55.9 GHz on bioluminescence activity of bacterium were investigated. Electromagnetic field results in decrease of bioluminescence, which depends from frequency. The electromagnetic field adaptation time is higher of intrinsic time parameters of bioluminescence system. The effect has nonthermal nature. It is suggested that electromagnetic field influence connects with structure rearrangements near cell emitter. 8 refs.; 3 figs

  11. Electromagnetic fields with vanishing scalar invariants

    Czech Academy of Sciences Publication Activity Database

    Ortaggio, Marcello; Pravda, Vojtěch

    2016-01-01

    Roč. 33, č. 11 (2016), s. 115010 ISSN 0264-9381 R&D Projects: GA ČR GA13-10042S Institutional support: RVO:67985840 Keywords : electromagnetic fields * n-dimensional spacetime * Einstein-Maxwell equations Subject RIV: BA - General Mathematics Impact factor: 3.119, year: 2016 http://dx.doi.org/10.1088/0264-9381/33/11/115010

  12. Magnetic nanoparticles with high specific absorption rate of electromagnetic energy at low field strength for hyperthermia therapy

    Science.gov (United States)

    Shubitidze, Fridon; Kekalo, Katsiaryna; Stigliano, Robert; Baker, Ian

    2015-03-01

    Magnetic nanoparticles (MNPs), referred to as the Dartmouth MNPs, which exhibit high specific absorption rate at low applied field strength have been developed for hyperthermia therapy applications. The MNPs consist of small (2-5 nm) single crystals of gamma-Fe2O3 with saccharide chains implanted in their crystalline structure, forming 20-40 nm flower-like aggregates with a hydrodynamic diameter of 110-120 nm. The MNPs form stable (>12 months) colloidal solutions in water and exhibit no hysteresis under an applied quasistatic magnetic field, and produce a significant amount of heat at field strengths as low as 100 Oe at 99-164 kHz. The MNP heating mechanisms under an alternating magnetic field (AMF) are discussed and analyzed quantitatively based on (a) the calculated multi-scale MNP interactions obtained using a three dimensional numerical model called the method of auxiliary sources, (b) measured MNP frequency spectra, and (c) quantified MNP friction losses based on magneto-viscous theory. The frequency responses and hysteresis curves of the Dartmouth MNPs are measured and compared to the modeled data. The specific absorption rate of the particles is measured at various AMF strengths and frequencies, and compared to commercially available MNPs. The comparisons demonstrate the superior heating properties of the Dartmouth MNPs at low field strengths (therapy to deeper tumors that were previously non-viable targets, potentially enabling the treatment of some of the most difficult cancers, such as pancreatic and rectal cancers, without damaging normal tissue.

  13. Adenosine Receptors as a Biological Pathway for the Anti-Inflammatory and Beneficial Effects of Low Frequency Low Energy Pulsed Electromagnetic Fields

    Directory of Open Access Journals (Sweden)

    Katia Varani

    2017-01-01

    Full Text Available Several studies explored the biological effects of low frequency low energy pulsed electromagnetic fields (PEMFs on human body reporting different functional changes. Much research activity has focused on the mechanisms of interaction between PEMFs and membrane receptors such as the involvement of adenosine receptors (ARs. In particular, PEMF exposure mediates a significant upregulation of A2A and A3ARs expressed in various cells or tissues involving a reduction in most of the proinflammatory cytokines. Of particular interest is the observation that PEMFs, acting as modulators of adenosine, are able to increase the functionality of the endogenous agonist. By reviewing the scientific literature on joint cells, a double role for PEMFs could be hypothesized in vitro by stimulating cell proliferation, colonization of the scaffold, and production of tissue matrix. Another effect could be obtained in vivo after surgical implantation of the construct by favoring the anabolic activities of the implanted cells and surrounding tissues and protecting the construct from the catabolic effects of the inflammatory status. Moreover, a protective involvement of PEMFs on hypoxia damage in neuron-like cells and an anti-inflammatory effect in microglial cells have suggested the hypothesis of a positive impact of this noninvasive biophysical stimulus.

  14. A forgotten argument by Gordon uniquely selects Abraham's tensor as the energy-momentum tensor for the electromagnetic field in homogeneous, isotropic matter

    International Nuclear Information System (INIS)

    Antoci, S.; Mihich, L.

    1997-01-01

    Given the present status of the problem of the electromagnetic energy tensor in matter, there is perhaps use in recalling a forgotten argument given in 1923 by W. Gordon. Let us consider a material medium which is homogeneous and isotropic when observed in its rest frame. For such a medium, Gordon's argument allows to reduce the above-mentioned problem to an analogous one, defined in a general relativistic vacuum. For the latter problem the form of the Lagrangian is known already, hence the determination of the energy tensor is a straightforward matter. One just performs the Hamiltonian derivative of the Lagrangian chosen in this way with respect to the true metric g ik . Abraham's tensor is thus selected as the electromagnetic energy tensor for a medium which is homogeneous and isotropic in its rest frame

  15. Influence of electromagnetic signal of antibiotics excited by low-frequency pulsed electromagnetic fields on growth of Escherichia coli.

    Science.gov (United States)

    Ke, Yin-Lung; Chang, Fu-Yu; Chen, Ming-Kun; Li, Shun-Lai; Jang, Ling-Sheng

    2013-01-01

    Energy medicine (EM) provides a new medical choice for patients, and its advantages are the noninvasive detection and nondrug treatment. An electromagnetic signal, a kind of EM, induced from antibiotic coupling with weak, extremely low-frequency pulsed electromagnetic fields (PEMFs) is utilized for investigating the growth speed of Escherichia coli (E. coli). PEMFs are produced by solenoidal coils for coupling the electromagnetic signal of antibiotics (penicillin). The growth retardation rate (GRR) of E. coli is used to investigate the efficacy of the electromagnetic signal of antibiotics. The E. coli is cultivated in the exposure of PEMFs coupling with the electromagnetic signal of antibiotics. The maximum GRR of PEMFs with and without the electromagnetic signal of antibiotics on the growth of E. coli cells in the logarithmic is 17.4 and 9.08%, respectively. The electromagnetic signal of antibiotics is successfully coupled by the electromagnetic signal coupling instrument to affect the growth of E. coli. In addition, the retardation effect on E. coli growth can be improved of by changing the carrier frequency of PEMFs coupling with the electromagnetic signal of antibiotics. GRR caused by the electromagnetic signal of antibiotics can be fixed by a different carrier frequency in a different phase of E. coli growth.

  16. Electromagnetic fields with vanishing quantum corrections

    Science.gov (United States)

    Ortaggio, Marcello; Pravda, Vojtěch

    2018-04-01

    We show that a large class of null electromagnetic fields are immune to any modifications of Maxwell's equations in the form of arbitrary powers and derivatives of the field strength. These are thus exact solutions to virtually any generalized classical electrodynamics containing both non-linear terms and higher derivatives, including, e.g., non-linear electrodynamics as well as QED- and string-motivated effective theories. This result holds not only in a flat or (anti-)de Sitter background, but also in a larger subset of Kundt spacetimes, which allow for the presence of aligned gravitational waves and pure radiation.

  17. Beta decay and other processes in strong electromagnetic fields

    International Nuclear Information System (INIS)

    Akhmedov, E. Kh.

    2011-01-01

    We consider effects of the fields of strong electromagnetic waves on various characteristics of quantum processes. After a qualitative discussion of the effects of external fields on the energy spectra and angular distributions of the final-state particles as well as on the total probabilities of the processes (such as decay rates and total cross sections), we present a simple method of calculating the total probabilities of processes with production of nonrelativistic charged particles. Using nuclear β decay as an example, we study the weak- and strong-field limits, as well as the field-induced β decay of nuclei stable in the absence of the external fields, both in the tunneling and multiphoton regimes. We also consider the possibility of accelerating forbidden nuclear β decays by lifting the forbiddeness due to the interaction of the parent or daughter nuclei with the field of a strong electromagnetic wave. It is shown that for currently attainable electromagnetic fields all effects on total β-decay rates are unobservably small.

  18. Electromagnetic or other directed energy pulse launcher

    Science.gov (United States)

    Ziolkowski, Richard W.

    1990-01-01

    The physical realization of new solutions of wave propagation equations, such as Maxwell's equations and the scaler wave equation, produces localized pulses of wave energy such as electromagnetic or acoustic energy which propagate over long distances without divergence. The pulses are produced by driving each element of an array of radiating sources with a particular drive function so that the resultant localized packet of energy closely approximates the exact solutions and behaves the same.

  19. Electron scattering in the presence of an intense electromagnetic field

    International Nuclear Information System (INIS)

    Mohan, M.; Chand, P.

    1977-03-01

    The general theory of electron scattering in the presence of an external electromagnetic field, provided by an intense laser beam, accompanied by absorption of n photons, each with energy hω, is discussed. The calculation leads to many summations over intermediate states. A general method for exactly evaluating several sums is described in detail. Numerical results show that the cross-section varies with intensity in a power law fashion

  20. Electromagnetic fields, pacemakers and defibrillators; Champs electromagnetiques, cardiostimulateurs et defibrillateurs

    Energy Technology Data Exchange (ETDEWEB)

    Guiguet, J.C. [Agence Nationale des Frequences (ANFR), 94 - Maisons Alfort (France); Dodinot, B.; Sadoul, N.; Blangy, H. [Centre Hospitalier Universitaire Nancy-Brabois, Clinique Cardiologique, 54 - Vandoeuvre Brabois (France); Nadi, M.; Hedjiedj, A.; Schmitt, P. [Universite Henri Poincare-Nancy, Lab. d' Instrumentation Electronique de Nancy, Faculte des Sciences, 54 - Vandoeuvre les Nancy (France); Joly, L.; Dodinot, B.; Aliot, E. [Centre Hospitalier Universitaire Nancy-Brabois, Service de Cardiologie, 54 - Vandoeuvre-les-Nancy (France); Silny, J. [Aachen University (Germany); Franck, R.; Himbert, C.; Hidden-Lucet, F.; Petitot, J.C.; Fontaine, G. [Hopital Pitie-Salpetriere, Institut de Cardiologie, Service de Rythmologie, 75 - Paris (France); Souques, M.; Lambrozo, J. [Electricite de France (EDF-Gaz de France), Service des Etudes Medicales, 75 - Paris (France); Magne, I.; Bailly, J.M. [Electricite de France (EDF-Gaz de France), Div. Recherche Developpement, 77 - Moret sur Loing (France); Trigano, J.A. [Centre Hospitalier Universitaire, Hopital Nord, 13 - Marseille (France); Burais, N. [CEGELY, Ecole Centrale de Lyon, 69 - Ecully (France); Gaspard, J.Y. [Magtech, 69 - Ecully (France); Andrivet, Ph. [Societe Medtronic France, 92 - Boulogne-Billancourt (France)

    2004-07-01

    Presentation of electromagnetic sources constituted by various radio transmitters contributing to different radio communication services in the environment. Results of a measures campaign to assess the electromagnetic field in the close neighbourhood of various stations. Analysis by frequency domains. (author)

  1. Influence of extremely low frequency, low energy electromagnetic fields and combined mechanical stimulation on chondrocytes in 3-D constructs for cartilage tissue engineering.

    Science.gov (United States)

    Hilz, Florian M; Ahrens, Philipp; Grad, Sibylle; Stoddart, Martin J; Dahmani, Chiheb; Wilken, Frauke L; Sauerschnig, Martin; Niemeyer, Philipp; Zwingmann, Jörn; Burgkart, Rainer; von Eisenhart-Rothe, Rüdiger; Südkamp, Norbert P; Weyh, Thomas; Imhoff, Andreas B; Alini, Mauro; Salzmann, Gian M

    2014-02-01

    Articular cartilage, once damaged, has very low regenerative potential. Various experimental approaches have been conducted to enhance chondrogenesis and cartilage maturation. Among those, non-invasive electromagnetic fields have shown their beneficial influence for cartilage regeneration and are widely used for the treatment of non-unions, fractures, avascular necrosis and osteoarthritis. One very well accepted way to promote cartilage maturation is physical stimulation through bioreactors. The aim of this study was the investigation of combined mechanical and electromagnetic stress affecting cartilage cells in vitro. Primary articular chondrocytes from bovine fetlock joints were seeded into three-dimensional (3-D) polyurethane scaffolds and distributed into seven stimulated experimental groups. They either underwent mechanical or electromagnetic stimulation (sinusoidal electromagnetic field of 1 mT, 2 mT, or 3 mT; 60 Hz) or both within a joint-specific bioreactor and a coil system. The scaffold-cell constructs were analyzed for glycosaminoglycan (GAG) and DNA content, histology, and gene expression of collagen-1, collagen-2, aggrecan, cartilage oligomeric matrix protein (COMP), Sox9, proteoglycan-4 (PRG-4), and matrix metalloproteinases (MMP-3 and -13). There were statistically significant differences in GAG/DNA content between the stimulated versus the control group with highest levels in the combined stimulation group. Gene expression was significantly higher for combined stimulation groups versus static control for collagen 2/collagen 1 ratio and lower for MMP-13. Amongst other genes, a more chondrogenic phenotype was noticed in expression patterns for the stimulated groups. To conclude, there is an effect of electromagnetic and mechanical stimulation on chondrocytes seeded in a 3-D scaffold, resulting in improved extracellular matrix production. © 2013 Wiley Periodicals, Inc.

  2. Low frequency electromagnetic fields and health problems

    International Nuclear Information System (INIS)

    Zahedi, A.; Cosic, I.

    1996-01-01

    Full text: Electromagnetic fields developed around the electric circuits are considered as magnetic pollution and these fields are produced wherever electric appliances or machinery are used at home as well as at workplace. Electric fields and magnetic fields around the home are produced by anything with electric current flowing through it including: the street power lines, the home wiring system, electric ovens, refrigerators, washing machines, electric clothes dryers, vacuum cleaners, television sets, video cassette recorders, toasters, light bulbs, clock radios, electric blankets, mobile phones, etc. In the workplace they would be produced by: nearby power lines, factory machinery, computers/video display units, lights, photocopiers, electrical cabling etc. As one can see, human life is strongly dependent on using-electric appliance. A large number of studies have been undertaken to find out the correlation between electromagnetic fields and health problems. The following significant results have been reported [Lerner E.J., IEEE Spectrum, 57-67, May 1984]: (a) Induction of chromosomal defects in mice spermatogenetic cells following microwave radiation in the Ghz range; (b) Changes in the calcium balance of living cats' brains exposed to microwaves modulated at extremely low frequencies; (c) Alternation of nerve and bone cells exposed to extremely low frequency fields; (d) Decreased activity of the immune cells of mice exposed to modulated microwaves; (e) Apparent increase in deformed foetuses among miniature swine exposed to intense power-line frequency fields. The mostly investigated effect is the effect of electromagnetic irradiation in particular one produced by power lines, and cancer. More than 100 epidemiological studies have been reported but no conclusive result was achieved. A number of studies with laboratory animals were also inconclusive. However, some of these experiments have shown improvements in immune system and tumour suppression when

  3. Designing localized electromagnetic fields in a source-free space

    International Nuclear Information System (INIS)

    Borzdov, George N.

    2002-01-01

    An approach to characterizing and designing localized electromagnetic fields, based on the use of differentiable manifolds, differentiable mappings, and the group of rotation, is presented. By way of illustration, novel families of exact time-harmonic solutions to Maxwell's equations in the source-free space - localized fields defined by the rotation group - are obtained. The proposed approach provides a broad spectrum of tools to design localized fields, i.e., to build-in symmetry properties of oscillating electric and magnetic fields, to govern the distributions of their energy densities (both size and form of localization domains), and to set the structure of time-average energy fluxes. It is shown that localized fields can be combined as constructive elements to obtain a complex field structure with desirable properties, such as one-, two-, or three-dimensional field gratings. The proposed approach can be used in designing localized electromagnetic fields to govern motion and state of charged and neutral particles. As an example, motion of relativistic electrons in one-dimensional and three-dimensional field gratings is treated

  4. Child leukaemia and low frequency electromagnetic fields

    International Nuclear Information System (INIS)

    Clavel, J.

    2009-01-01

    The author discusses the possible causes of child leukaemia: exposure to natural ionizing radiation (notably radon), to pesticides, and to hydrocarbons emitted by road traffic. Some studies suggested that an inadequate reaction of the immune system to an ordinary infection could result in leukaemia. Other factors are suspected, notably extremely low frequency electromagnetic fields, the influence of which is then discussed by the author. She evokes and discusses results of different investigations on this topic which have been published since the end of the 1970's. It appears that a distance less than 50 meters from high voltage lines or the vicinity of transformation stations may double the risk of child leukaemia

  5. The Biological Effects of Weak Electromagnetic Fields

    International Nuclear Information System (INIS)

    Algattawi, A.; Elshyrih, H.

    2010-01-01

    Many studies investigated that weak electromagnetic fields remove calcium ions bound to the membranes of living cells, making them more likely to tear,. There is an enzyme that destroys DNA this enzyme leaking through the membranes of lysosomes explains the fragmentation of DNA. This case was seen in cells exposed to mobile phone signals. When this occurs in the germ line it reduces fertility and predicts genetic damage in future generations. Although leakage of calcium ions into the cytosol (the main part of the cell) accelerates the growth, but it also promotes the growth of tumors. Leakage of calcium ions into neurons (brain cells) makes nerve impulses accounting for pain and other neurological symptoms in electro sensitive. It also reduces the signal to noise ratio of the brain making it less likely to respond. This may be partially responsible for the increased accident rate of drivers using mobile phones. More details for the molecular mechanisms to explain characteristics of electromagnetic exposure are needed, e.g. I) why weak fields are more effective than strong ones, II) why some frequencies such as 16 Hz are especially potent and III) why pulsed fields do more damage

  6. Electromagnetic fields of rotating magnetized NUT stars

    International Nuclear Information System (INIS)

    Ahmedov, B.J.; Khugaev, A.V.; Ahmedov, B.J.

    2004-01-01

    Full text: Analytic general relativistic expressions for the electromagnetic fields external to a slowly-rotating magnetized NUT star with nonvanishing gravitomagnetic charge have been presented. Solutions for the electric and magnetic fields have been found after separating the Maxwell equations in the external background spacetime of a slowly rotating NUT star into angular and radial parts in the lowest order approximation. The star is considered isolated and in vacuum, with different models for stellar magnetic field: i) monopolar magnetic field and II) dipolar magnetic field aligned with the axis of rotation. We have shown that the general relativistic corrections due to the dragging of reference frames and gravitomagnetic charge are not present in the form of the magnetic fields but emerge only in the form of the electric fields. In particular, we have shown that the frame-dragging and gravitomagnetic charge provide an additional induced electric field which is analogous to the one introduced by the rotation of the star in the flat spacetime limit

  7. Electromagnetic Field Redistribution in Metal Nanoparticle on Graphene.

    Science.gov (United States)

    Li, Keke; Liu, Anping; Wei, Dapeng; Yu, Keke; Sun, Xiaonan; Yan, Sheng; Huang, Yingzhou

    2018-04-25

    Benefiting from the induced image charge on metal film, the light energy is confined on a film surface under metal nanoparticle dimer, which is called electromagnetic field redistribution. In this work, electromagnetic field distribution of metal nanoparticle monomer or dimer on graphene is investigated through finite-difference time-domain method. The results point out that the electromagnetic field (EM) redistribution occurs in this nanoparticle/graphene hybrid system at infrared region where light energy could also be confined on a monolayer graphene surface. Surface charge distribution was analyzed using finite element analysis, and surface-enhanced Raman spectrum (SERS) was utilized to verify this phenomenon. Furthermore, the data about dielectric nanoparticle on monolayer graphene demonstrate this EM redistribution is attributed to strong coupling between light-excited surface charge on monolayer graphene and graphene plasmon-induced image charge on dielectric nanoparticle surface. Our work extends the knowledge of monolayer graphene plasmon, which has a wide range of applications in monolayer graphene-related film.

  8. On absorption of low frequency electromagnetic fields

    International Nuclear Information System (INIS)

    Brunner, S.; Vaclavik, J.

    1993-03-01

    The drift kinetic equation (DKE) is used to establish a formula for power absorption of small amplitude, low frequency electromagnetic (EM) fields in a hot toroidal axisymmetric plasma. The stationary plasma is first considered. Electrons and ions are described by local Maxwellian distributions, alpha particles by a local slowing-down distribution. The fluctuating part of the distribution function for each species is then evaluated from the linearized DKE in terms of the EM fields using a perturbation method. The parameter b p =B p /B o , where B p is the poloidal component of the magnetostatic field B o , and the parameter v d /λω, where v d is the magnetic curvature drift, λ the wavelength perpendicular to B o and ω the frequency of the EM fields, are considered to be small. By integrating the resulting distribution function over velocity space, an explicit formula for the power absorbed by each species is obtained. To obtain an expression suitable for direct implementation in an ideal-MHD code, the electric field component parallel to the magnetostatic field is evaluated using the quasi-neutrality equation. (author) 4 refs

  9. Evaluation of uncertainty in the measurement of environmental electromagnetic fields

    International Nuclear Information System (INIS)

    Vulevic, B.; Osmokrovic, P.

    2010-01-01

    With regard to Non-ionising radiation protection, the relationship between human exposure to electromagnetic fields and health is controversial. Electromagnetic fields have become omnipresent in the daily environment. This paper assesses the problem of how to compare a measurement result with a limit fixed by the standard for human exposure to electric, magnetic and electromagnetic fields (0 Hz-300 GHz). The purpose of the paper is an appropriate representation of the basic information about evaluation of measurement uncertainty. (authors)

  10. The classical theory of fields electromagnetism

    CERN Document Server

    Helrich, Carl S

    2012-01-01

    The study of classical electromagnetic fields is an adventure. The theory is complete mathematically and we are able to present it as an example of classical Newtonian experimental and mathematical philosophy. There is a set of foundational experiments, on which most of the theory is constructed. And then there is the bold theoretical proposal of a field-field interaction from James Clerk Maxwell. This textbook presents the theory of classical fields as a mathematical structure based solidly on laboratory experiments. Here the student is introduced to the beauty of classical field theory as a gem of theoretical physics. To keep the discussion fluid, the history is placed in a beginning chapter and some of the mathematical proofs in the appendices. Chapters on Green’s Functions and Laplace’s Equation and a discussion of Faraday’s Experiment further deepen the understanding. The chapter on Einstein’s relativity is an integral necessity to the text. Finally, chapters on particle motion and waves in a dis...

  11. Electromagnetic fields in small systems from a multiphase transport model

    Science.gov (United States)

    Zhao, Xin-Li; Ma, Yu-Gang; Ma, Guo-Liang

    2018-02-01

    We calculate the electromagnetic fields generated in small systems by using a multiphase transport (AMPT) model. Compared to A +A collisions, we find that the absolute electric and magnetic fields are not small in p +Au and d +Au collisions at energies available at the BNL Relativistic Heavy Ion Collider and in p +Pb collisions at energies available at the CERN Large Hadron Collider. We study the centrality dependencies and the spatial distributions of electromagnetic fields. We further investigate the azimuthal fluctuations of the magnetic field and its correlation with the fluctuating geometry using event-by-event simulations. We find that the azimuthal correlation 〈" close="〉cos(ϕα+ϕβ-2 ΨRP)〉">cos2 (ΨB-Ψ2) between the magnetic field direction and the second-harmonic participant plane is almost zero in small systems with high multiplicities, but not in those with low multiplicities. This indicates that the charge azimuthal correlation is not a valid probe to study the chiral magnetic effect (CME) in small systems with high multiplicities. However, we suggest searching for possible CME effects in small systems with low multiplicities.

  12. Nonstationary random acoustic and electromagnetic fields as wave diffusion processes

    International Nuclear Information System (INIS)

    Arnaut, L R

    2007-01-01

    We investigate the effects of relatively rapid variations of the boundaries of an overmoded cavity on the stochastic properties of its interior acoustic or electromagnetic field. For quasi-static variations, this field can be represented as an ideal incoherent and statistically homogeneous isotropic random scalar or vector field, respectively. A physical model is constructed showing that the field dynamics can be characterized as a generalized diffusion process. The Langevin-It o-hat and Fokker-Planck equations are derived and their associated statistics and distributions for the complex analytic field, its magnitude and energy density are computed. The energy diffusion parameter is found to be proportional to the square of the ratio of the standard deviation of the source field to the characteristic time constant of the dynamic process, but is independent of the initial energy density, to first order. The energy drift vanishes in the asymptotic limit. The time-energy probability distribution is in general not separable, as a result of nonstationarity. A general solution of the Fokker-Planck equation is obtained in integral form, together with explicit closed-form solutions for several asymptotic cases. The findings extend known results on statistics and distributions of quasi-stationary ideal random fields (pure diffusions), which are retrieved as special cases

  13. Electromagnetic field and mechanical stress analysis code

    International Nuclear Information System (INIS)

    1978-01-01

    Analysis TEXMAGST is a two stage linear finite element code for the analysis of static magnetic fields in three dimensional structures and associated mechanical stresses produced by the anti J x anti B forces within these structures. The electromagnetic problem is solved in terms of magnetic vector potential A for a given current density anti J as curl 1/μ curl anti A = anti J considering the magnetic permeability as constant. The Coulombian gauge (div anti A = o) was chosen and was implemented through the use of Lagrange multipliers. The second stage of the problem - the calculation of mechanical stresses in the same three dimensional structure is solved by using the same code with few modifications - through a restart card. Body forces anti J x anti B within each element are calculated from the solution of the first stage run and represent the input to the second stage run which will give the solution for the stress problem

  14. Visualizing electromagnetic fields in metals by MRI

    Directory of Open Access Journals (Sweden)

    Chandrika Sefcikova Chandrashekar

    2017-02-01

    Full Text Available Based upon Maxwell’s equations, it has long been established that oscillating electromagnetic (EM fields incident upon a metal surface, decay exponentially inside the conductor, leading to a virtual absence of EM fields at sufficient depths. Magnetic resonance imaging (MRI utilizes radiofrequency (r.f. EM fields to produce images. Here we present a visualization of a virtual EM vacuum inside a bulk metal strip by MRI, amongst several findings. At its simplest, an MRI image is an intensity map of density variations across voxels (pixels of identical size (=Δx Δy Δz. By contrast in bulk metal MRI, we uncover that despite uniform density, intensity variations arise from differing effective elemental volumes (voxels from different parts of the bulk metal. Further, we furnish chemical shift imaging (CSI results that discriminate different faces (surfaces of a metal block according to their distinct nuclear magnetic resonance (NMR chemical shifts, which holds much promise for monitoring surface chemical reactions noninvasively. Bulk metals are ubiquitous, and MRI is a premier noninvasive diagnostic tool. Combining the two, the emerging field of bulk metal MRI can be expected to grow in importance. The findings here may impact further development of bulk metal MRI and CSI.

  15. The electromagnetic field equations for moving media

    International Nuclear Information System (INIS)

    Ivezić, T

    2017-01-01

    In this paper a formulation of the field equation for moving media is developed by the generalization of an axiomatic geometric formulation of the electromagnetism in vacuum (Ivezić T 2005 Found. Phys. Lett. 18 401). First, the field equations with bivectors F ( x ) and ℳ ( x ) are presented and then these equations are written with the 4D vectors E ( x ), B ( x ), P ( x ) and M ( x ). The latter contain both the 4D velocity vector u of a moving medium and the 4D velocity vector v of the observers who measure E and B fields. They do not appear in previous literature. All these equations are also written in the standard basis and compared with Maxwell’s equations with 3D vectors. In this approach the Ampère-Maxwell law and Gauss’s law are inseparably connected in one law and the same happens with Faraday’s law and the law that expresses the absence of magnetic charge. It is shown that Maxwell’s equations with 3D vectors and the field equations with 4D geometric quantities are not equivalent in 4D spacetime (paper)

  16. Relations between focusing power of space-charge lenses and external electromagnetic fields

    International Nuclear Information System (INIS)

    Yu Qingchang; Qiu Hong; Huang Jiachang

    1991-01-01

    Under different external electromagnetic fields, the electron densities of the electron cloud in a self-sustaning spece-charge lens are measured with the radio-frequency method and the energy distributions of the ions produced in ionization are measured with the stopping field method. From them the relations between the focusing power of space-charge lenses and the external electromagnetic fields are determined. The available region of the Lebedev-Morozov formula is discussed

  17. Electromagnetic and gravitational scattering at Planckian energies

    International Nuclear Information System (INIS)

    Das, S.; Majumdar, P.

    1994-11-01

    The scattering of pointlike particles at very large center of mass energies and fixed low momentum transfers, occurring due to both their electromagnetic and gravitational interactions is re-examined in the particular case when one of the particles carries magnetic charge. At Planckian center-of-mass energies, when gravitational dominance is normally expected, the presence of magnetic charge is shown to produce dramatic modifications to the scattering cross section as well as to the holomorphic structure of the scattering amplitude. (author). 20 refs

  18. Effects of Electromagnetic Fields on Fish and Invertebrates Task 2.1.3: Effects on Aquatic Organisms Fiscal Year 2012 Progress Report Environmental Effects of Marine and Hydrokinetic Energy

    Energy Technology Data Exchange (ETDEWEB)

    Woodruff, Dana L.; Cullinan, Valerie I.; Copping, Andrea E.; Marshall, Kathryn E.

    2013-05-20

    Energy generated by the world’s oceans and rivers offers the potential to make substantial contributions to the domestic and global renewable energy supply. However, the marine and hydrokinetic (MHK) energy industry faces challenges related to siting, permitting, construction, and operation of pilotand commercial-scale facilities. One of the challenges is to understand the potential effects to marine organisms from electromagnetic fields, which are produced as a by-product of transmitting power from offshore to onshore locations through underwater transmission cables. This report documents the progress of the third year of research (fiscal year 2012) to investigate environmental issues associated with marine and hydrokinetic energy (MHK) generation. This work was conducted by Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy’s (DOE’s) Office of Energy Efficiency and Renewable Energy (EERE) Wind and Water Technologies Office. The report addresses the effects of electromagnetic fields (EMFs) on selected marine species where significant knowledge gaps exist. The species studied this fiscal year included one fish and two crustacean species: the Atlantic halibut (Hippoglossus hippoglossus), Dungeness crab (Metacarcinus magister), and American lobster (Homarus americanus).

  19. Utilizing scalar electromagnetics to tap vacuum energy

    International Nuclear Information System (INIS)

    Sweet, F.; Bearden, T.E.

    1991-01-01

    Based on E.T. Whittaker's previously unnoticed 1903-1904 papers which established a hidden bidirectional EM wave structure in a standing forcefield free scalar potential, a method of directly engineering the ambient potential of the vacuum has been developed and realized experimentally. Adding Whittaker's engineerable hidden variable theory to classical electromagnetic, quantum mechanics, and general relativity produces supersets of each discipline. These supersets are joined by the common Whittaker subset, producing a unified field theory that is engineerable and tested. By treating the nucleus of the atom as a pumped phase conjugate mirror, several working model energy units have been produced which excite and organize the local vacuum, increase the local virtual photon flux between local vacuum and nucleus, establish coherent self-oscillations between the local excited vacuum and the affected nuclei, utilized the self-oscillating standing wave for self-pumping of the nuclei/mirrors, introduce a very tiny signal wave to the mirrors, and output into an external load circuit a powerful, amplified, time-reversed phase conjugate replica wave at 60 Hertz frequency and nominal 120 volt sine wave power. Several models have been built, ranging from 6 watts early on to one of 5 kilowatts. Both closed battery-less systems with damped positive feedback and open loop systems with battery-powered input have been successfully built. Open loop power gains of from 5 x 10 4 to 1.5 x 10 6 have been achieved. Antigravity experiments have also been successfully conducted where the weight of the unit was reduced by 90% in controlled experiments, with a signal wave input of 175 microwatts and an output of 1 kilowatt. The basic theory of the device is briefly explained and experimental results presented

  20. Geometrization of the electromagnetic field and dark matter

    International Nuclear Information System (INIS)

    Pestov, I.B.

    2005-01-01

    A general concept of potential field is introduced. The potential field that one puts in correspondence with dark matter, has fundamental geometrical interpretation (parallel transport) and has intrinsically inherent local symmetry. The equations of dark matter field are derived that are invariant with respect to the local transformations. It is shown how to reduce these equations to the Maxwell equations. Thus, the dark matter field may be considered as generalized electromagnetic field and a simple solution of the old problem is given to connect electromagnetic field with geometrical properties of the physical manifold itself. It is shown that gauge fixing renders generalized electromagnetic field effectively massive while the Maxwell electromagnetic field remains massless. To learn more about interactions between matter and dark matter on the microscopical level (and to recognize the fundamental role of internal symmetry) the general covariant Dirac equation is derived in the Minkowski space-time which describes the interactions of spinor field with dark matter field

  1. The Universal C*-Algebra of the Electromagnetic Field

    Science.gov (United States)

    Buchholz, Detlev; Ciolli, Fabio; Ruzzi, Giuseppe; Vasselli, Ezio

    2016-02-01

    A universal C*-algebra of the electromagnetic field is constructed. It is represented in any quantum field theory which incorporates electromagnetism and expresses basic features of the field such as Maxwell's equations, Poincaré covariance and Einstein causality. Moreover, topological properties of the field resulting from Maxwell's equations are encoded in the algebra, leading to commutation relations with values in its center. The representation theory of the algebra is discussed with focus on vacuum representations, fixing the dynamics of the field.

  2. Electromagnetic field, excited by monodirected X-radiation pulse

    International Nuclear Information System (INIS)

    Zhemerov, A.V.; Metelkin, E.V.

    1994-01-01

    Parameters of electromagnetic field, generated in the atmosphere by monodirected pulse source of X radiation located at the altitude of approximately several kilometers have been estimated by the method of delayed potentials. The source radiation is directed towards the Earth surface. The conclusion was made that restricted areas of approximately 1 km with considerable pulse electromagnetic fields can be created on the Earth surface

  3. Hydrodynamic view of electrodynamics: energy rays and electromagnetic effective stress

    International Nuclear Information System (INIS)

    Chou, Chia-Chun; Wyatt, Robert E

    2011-01-01

    Energy rays ('photon trajectories') based upon the hydrodynamic formulation of electrodynamics are presented for time-dependent electromagnetic wave propagation. We derive Cauchy's equation of motion for the electromagnetic effective force governing the dynamics of energy rays. The effective force generated by the electromagnetic effective stress provides a surface force acting on the energy fluid element. For the head-on collision of two electromagnetic Gaussian pulses, the electromagnetic effective force, analogous to the role played by the quantum force in Bohmian mechanics, guides these non-crossing energy rays. For an electromagnetic pulse traveling from free space to a dielectric medium, the energy rays guided by the electromagnetic effective stress display reflection and refraction at the interface.

  4. Interacting massless scalar and source-free electromagnetic fields

    International Nuclear Information System (INIS)

    Ayyangar, B.R.N.; Mohanty, G.

    1985-01-01

    The relativistic field equations for interacting massless attractive scalar and source-free electromagnetic fields in a cylindrically symmetric spacetime of one degree of freedom with reflection symmetry have been reduced to a first order implicit differential equation depending on time which enables one to generate a class of solution to the field equations. The nature of the scalar and electromagnetic fields is discussed. It is shown that the geometry of the spacetime admits of an irrotational stiff fluid distribution without prejudice to the interacting electromagnetic fields. 10 refs. (author)

  5. Exposure to power frequency electromagnetic fields

    International Nuclear Information System (INIS)

    Skotte, J.

    1993-01-01

    The purpose was to asses personal exposure to power frequency electromagnetic fields in Denmark. Exposure to electrical and magnetic 50 Hz fields were measured with personal dosimeters in periods of 24 hours covering both occupational and residential environments. The study included both highly exposed and 'normal' exposed jobs. Measurements were carried out with dosimeters, which sample electrical and magnetic fields every 5 sec. Participants also wore the dosimeter during transportation. The dynamic range of the dosimeters was 0.01-200 μT and 0.6-10000 V/m. The highest average exposure in homes near high power lines was 2.24 μT. In most homes without nearby high power lines the average exposure was below 0.05 μT. Average values of '24-hour-dose' (μT times hours) for the generator facility, transmission line and substation workers were approximately the same as for the people living near high power lines (5 μT x hours). Electric field measurements with personal dosimeters involve several factors of uncertainty, as the body, posture, position of dosimeter etc. influence the results. The highest exposed groups were transmission line workers (GM: 44 V/m) and substation workers (GM: 23 V/m) but there were large variations (GSD: 4.7-4.8). In the work time the exposure level was the same for office workers and workers in the industry groups (GM: 12-13 V/m). In homes near high power lines (GM: 23 V/m) there was a non-significant tendency to higher exposure compared to homes without nearby high power lines. (AB) (11 refs.)

  6. Nonlinear metamaterials for electromagnetic energy harvesting (Conference Presentation)

    Science.gov (United States)

    Oumbe Tekam, Gabin Thibaut; Ginis, Vincent; Seetharamdoo, Divitha; Danckaert, Jan

    2016-09-01

    Surrounded by electromagnetic radiation coming from wireless power transfer to consumer devices such as mobile phones, computers and television, our society is facing the scientific and technological challenge to recover energy that is otherwise lost to the environment. Energy harvesting is an emerging field of research focused on this largely unsolved problem, especially in the microwave regime. Metamaterials provide a very promising platform to meet this purpose. These artificial materials are made from subwavelength building blocks, and can be designed by resonate at particular frequencies, depending on their shape, geometry, size, and orientation. In this work, we show that an efficient electromagnetic energy harvester can be design by inserting a nonlinear element directly within the metamaterial unit cell, leading to the conversion of RF input power to DC charge accumulation. The electromagnetic energy harvester operating at microwave frequencies is built from a cut-wire metasurface, which operates as a quasistatic electric dipole resonator. Using the equivalent electrical circuit, we design the parameters to tune the resonance frequency of the harvester at the desired frequency, and we compare these results with numerical simulations. Finally, we discuss the efficiency of our metamaterial energy harvesters. This work potentially offers a variety of applications, for example in the telecommunications industry to charge phones, in robotics to power microrobots, and also in medicine to advance pacemakers or health monitoring sensors.

  7. Electromagnetic energy harvester for harvesting acoustic energy

    Indian Academy of Sciences (India)

    Farid U Khan

    SPLs) both in ... several ambient energies such as wind, thermal, vibration, and solar are available and have been successfully trans- ..... mentsTM data acquisition (DAQ) card and NI LabVIEW software is used to acquire the signals from the ...

  8. Electromagnetic field in higher-dimensional black-hole spacetimes

    International Nuclear Information System (INIS)

    Krtous, Pavel

    2007-01-01

    A special test electromagnetic field in the spacetime of the higher-dimensional generally rotating NUT-(anti-)de Sitter black hole is found. It is adjusted to the hidden symmetries of the background represented by the principal Killing-Yano tensor. Such an electromagnetic field generalizes the field of charged black hole in four dimensions. In higher dimensions, however, the gravitational backreaction of such a field cannot be consistently solved

  9. New foundations for applied electromagnetics the spatial structure of fields

    CERN Document Server

    Mikki, Said

    2016-01-01

    This comprehensive new resource focuses on applied electromagnetics and takes readers beyond the conventional theory with the use of contemporary mathematics to improve the practical use of electromagnetics in emerging areas of field communications, wireless power transfer, metamaterials, MIMO and direction-of-arrival systems. The book explores the existing and novel theories and principles of electromagnetics in order to help engineers analyze and design devices for todays applications in wireless power transfers, NFC, and metamaterials.

  10. Exposure of Nurses to Electromagnetic Fields

    International Nuclear Information System (INIS)

    Zmyslony, M.; Mamrot, P.; Politanski, P.

    2004-01-01

    Devices that produce electromagnetic fields (EMF) within the range of 0-300 GHz are widely used in surgical and diagnostic procedures. As a result a large number of physicians and other groups of medical personnel may be exposed to EMF. Even if patients' exposure, sometimes quite high, is inevitable or even recommended, medical personnel should be substantially protected against EMF exposure. Evaluation of nurses' exposure to EMF was based on an analysis of EMF magnitudes in the surrounding of magnetic resonance imaging (MRI) and electrosurgical units. These two kinds of apparatus are the strongest EMF sources in health service facilities. The measurements were performed according to the norms and hygiene regulations binding in Poland. Measurements performed by the Nofer Institute of Medicine in Lodz, and data collected by the Central Database on EMF Sources were used in the analysis. The Central Database is run by the Nofer Institute of Medicine at the behest of the Chief Sanitary Inspector. The study showed that nurses' exposure to EMF emitted by MRI and electrosurgical units complies with Polish norms and hygiene regulations and can be classified as negligible or allowable. It was found that work of nurses in exposure to EMF emitted by MRI and electrosurgical units can be regarded as safe, which means that their health should not be endangered by the performed job. (author)

  11. Electromagnetic multipole fields of neutron stars

    International Nuclear Information System (INIS)

    Roberts, W.J.

    1979-01-01

    There is now indisputable evidence that some pulsars possess space velocities so high that internal asymmetries in the dynamics of their formation are strongly implied. We develop in this paper a complete formalism for the calculation of the only such mechanism that has yet been subjected to quantitative analysis: electromagnetic recoil radiation. To make the general problem tractable without doing violence to the physics, we have made the following simplifying assumptions: (1) the magnetic induction B in athin shell enclosing the surface can be satisfactorily approximated by a sum of vacuum multipole fields; (2) the star is spherical, and all parts are in good electrical contact; (3) vertical-bar Ω X r vertical-barvery-much-less-thanc everywhere within the star; and (4) the star is surrounded by a vacuum. Our qualitative conclusions hold even if these assumptions are violated, but corrections to our quantitative results required by a relaxation of our assumptions are not easily computed.Given this simple electrodynamic model of a neutron star, we solve the following problems: (1) What electric multipoles are induced by each magnetic multipole. (2) What is the general formula for the recoil produced by the projection on the rotational axis of a net linear momentum flux produced by the rotation of any two magnetic multipoles. (3) What is the set of centered multipoles that represents the field of an arbitrary off-centered multipole. We use these general results go perform a detailed analysis of the linear momentum radiated by an off-centered dipole. We find a force larger by a factor 6 than that obtained for the special case treated in the best previous calculation. In spite of this considerable increase in the computed strengrh of the effect, we still believe it to be too weak to produce the large space velocities observed for pulsars. For the mechanism to be effective, the pulsar must be born rotating near the breakup velocity

  12. Approximate theory the electromagnetic energy of solenoid in special relativity

    International Nuclear Information System (INIS)

    Prastyaningrum, I; Kartikaningsih, S.

    2017-01-01

    Solenoid is a device that is often used in electronic devices. A solenoid is electrified will cause a magnetic field. In our analysis, we just focus on the electromagnetic energy for solenoid form. We purpose to analyze by the theoretical approach in special relativity. Our approach is begun on the Biot Savart law and Lorentz force. Special theory relativity can be derived from the Biot Savart law, and for the energy can be derived from Lorentz for, by first determining the momentum equation. We choose the solenoid form with the goal of the future can be used to improve the efficiency of the electrical motor. (paper)

  13. [Dynamics of biomacromolecules in coherent electromagnetic radiation field].

    Science.gov (United States)

    Leshcheniuk, N S; Apanasevich, E E; Tereshenkov, V I

    2014-01-01

    It is shown that induced oscillations and periodic displacements of the equilibrium positions occur in biomacromolecules in the absence of electromagnetic radiation absorption, due to modulation of interaction potential between atoms and groups of atoms forming the non-valence bonds in macromolecules by the external electromagnetic field. Such "hyperoscillation" state causes inevitably the changes in biochemical properties of macromolecules and conformational transformation times.

  14. Overview on the standardization in the field of electromagnetic compatibility

    Science.gov (United States)

    Goldberg, Georges

    1989-04-01

    Standardization in the domain of electromagnetic compatibility (EMC) is discussed, with specific reference to the standards of the International Electrotechnical Commission, the Comite International Special des Perturbations Radioelectriques, and the Comite Europeen de Normalisation Electrotechnique. EMC fields considered include radiocommunications, telecommunications, biological effects, and data transmission. Standards are presented for such electromagnetic disturbances as low-frequency, high-frequency, conduction, and radiation phenomena.

  15. Spin and intrinsic angular momentum; application to the electromagnetic field

    International Nuclear Information System (INIS)

    Paillere, P.

    1993-05-01

    Within the framework of the field theory governed by a Lagrangian, function of the tensor quantities and their covariant first derivatives, and starting with the third order intrinsic angular momentum tensor obtained from a variational principle, the intrinsic angular momentum vector of the electromagnetic field in vacuum is determined. This expression leads to spin matrices for the electromagnetic field, with unity as eigenvalue, thus allowing to bridge the gap between continuous physics and quantum physics. 6 refs

  16. Schwinger mechanism in electromagnetic field in de Sitter spacetime

    Directory of Open Access Journals (Sweden)

    Bavarsad Ehsan

    2018-01-01

    Full Text Available We investigate Schwinger scalar pair production in a constant electromagnetic field in de Sitter (dS spacetime. We obtain the pair production rate, which agrees with the Hawking radiation in the limit of zero electric field in dS. The result describes how a cosmic magnetic field affects the pair production rate. In addition, using a numerical method we study the effect of the magnetic field on the induced current. We find that in the strong electromagnetic field the current has a linear response to the electric and magnetic fields, while in the infrared regime, is inversely proportional to the electric field and leads to infrared hyperconductivity.

  17. Energy harvesting devices for harvesting energy from terahertz electromagnetic radiation

    Science.gov (United States)

    Novack, Steven D.; Kotter, Dale K.; Pinhero, Patrick J.

    2012-10-09

    Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.

  18. A Unified Field Theory of Gravity, Electromagnetism, and the Yang-Mills Gauge Field

    Directory of Open Access Journals (Sweden)

    Suhendro I.

    2008-01-01

    Full Text Available In this work, we attempt at constructing a comprehensive four-dimensional unified field theory of gravity, electromagnetism, and the non-Abelian Yang-Mills gauge field in which the gravitational, electromagnetic, and material spin fields are unified as intrinsic geometric objects of the space-time manifold S4 via the connection, with the general- ized non-Abelian Yang-Mills gauge field appearing in particular as a sub-field of the geometrized electromagnetic interaction.

  19. Particle acceleration through the resonance of high magnetic field and high frequency electromagnetic wave

    International Nuclear Information System (INIS)

    Hong, Liu; He, X.T.; Chen, S.G.; Zhang, W.Y.; He, X.T.; Hong, Liu

    2004-01-01

    We propose a new particle acceleration mechanism. Electrons can be accelerated to relativistic energy within a few electromagnetic wave cycles through the mechanism which is named electromagnetic and magnetic field resonance acceleration (EMRA). We find that the electron acceleration depends not only on the electromagnetic wave intensity, but also on the ratio between electron Larmor frequency and electromagnetic wave frequency. As the ratio approaches to unity, a clear resonance peak is observed, corresponding to the EMRA. Near the resonance regime, the strong magnetic fields still affect the electron acceleration dramatically. We derive an approximate analytical solution of the relativistic electron energy in adiabatic limit, which provides a full understanding of this phenomenon. In typical parameters of pulsar magnetospheres, the mechanism allows particles to increase their energies through the resonance of high magnetic field and high frequency electromagnetic wave in each electromagnetic wave period. The energy spectra of the accelerated particles exhibit the synchrotron radiation behavior. These can help to understand the remaining emission of high energy electron from radio pulsar within supernova remnant. The other potential application of our theory in fast ignition scheme of inertial confinement fusion is also discussed. (authors)

  20. A Unified Field Theory of Gravity, Electromagnetism, and theA Unified Field Theory of Gravity, Electromagnetism, and the Yang-Mills Gauge Field

    Directory of Open Access Journals (Sweden)

    Suhendro I.

    2008-01-01

    Full Text Available In this work, we attempt at constructing a comprehensive four-dimensional unified field theory of gravity, electromagnetism, and the non-Abelian Yang-Mills gauge field in which the gravitational, electromagnetic, and material spin fields are unified as intrinsic geometric objects of the space-time manifold $S_4$ via the connection, with the generalized non-Abelian Yang-Mills gauge field appearing in particular as a sub-field of the geometrized electromagnetic interaction.

  1. Strong and Electromagnetic Interactions at SPS Energies

    CERN Document Server

    Ribicki, Andrzej

    2009-01-01

    Particle production in peripheral Pb+Pb collisions has been measured at a beam energy of 158 GeV per nucleon, corresponding to psNN 17.3 GeV. The measurements provide full double differential coverage in a wide range of longitudinal and transverse momenta, including the central (“mid-rapidity”) area and extending far into the projectile fragmentation region. The resulting analysis shows the heavy ion reaction as a mixture of different processes. In particular, surprising phenomena, like the presence of large and strongly varying structures in the shape of the double differential cross section d2s /dxFd pT , are induced by the final state electromagnetic interaction between produced particles and the charged spectator system. This effect is largest at low transverse momenta, where it results in a deep valley in the xF -dependence of the produced p+/p− ratio. The basic characteristics of the electromagnetic phenomenon described above agree with the results of a theoretical analysis, performed by means of ...

  2. MINERAL HORIZONS, ELECTROMAGNETIC FIELDS AND CIRCULAR SHAPES IN THE GRASS

    Directory of Open Access Journals (Sweden)

    Valentino Straser

    2009-12-01

    Full Text Available The occasional appearance of circular shapes in meadows and farmland located on slopes usually affected by gravitational phenomena, offered an occasion for verifying the possible relation between the position of the circles in the grass, the gravitational movement of the slope affecting its mineral horizons and the variations of electric and static magnetic fields close to the circular shapes and in the surrounding area. The stress caused by the “creeping” movement in the uderlying ground turned out to be in direct relation with the variation in the electric and magnetic fields caused by piezoelectric and piezomagnetic minerals such as quartz. The onset of the electromagnetic process involves the conversion of electric energy on the surface into an area of spherical shape which is linked with a different growth of herbaceous species compared to the surrounding vegetation.

  3. Simple formula for photoprocesses in ultrashort electromagnetic field

    International Nuclear Information System (INIS)

    Astapenko, V.A.

    2010-01-01

    Within the framework of the perturbation theory, a simple formula for the probability of a photoprocess for the whole time of action of an ultrashort electromagnetic pulse has been derived, when the concept of spectral intensity of radiation and probability per unit time is inapplicable. In the obtained formula the total probability is expressed in terms of the cross-section of a photoprocess in a monochromatic field and the Fourier transform of electric field strength. The advanced approach is applied for the analysis of photoabsorption of an atom and a metal nanosphere under the action of a subcycle laser pulse with a changeable value of the carrier-envelope phase. The expressions for probability and energy of photoabsorption in the limit of a zero pulse duration have been obtained.

  4. Electromagnetic field limits set by the V-Curve.

    Energy Technology Data Exchange (ETDEWEB)

    Warne, Larry Kevin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jorgenson, Roy Eberhardt [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hudson, Howard Gerald [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-07-01

    When emitters of electromagnetic energy are operated in the vicinity of sensitive components, the electric field at the component location must be kept below a certain level in order to prevent the component from being damaged, or in the case of electro-explosive devices, initiating. The V-Curve is a convenient way to set the electric field limit because it requires minimal information about the problem configuration. In this report we will discuss the basis for the V-Curve. We also consider deviations from the original V-Curve resulting from inductive versus capacitive antennas, increases in directivity gain for long antennas, decreases in input impedance when operating in a bounded region, and mismatches dictated by transmission line losses. In addition, we consider mitigating effects resulting from limited antenna sizes.

  5. Geometrization of the Electromagnetic Field and Dark Matter

    CERN Document Server

    Pestov, I B

    2005-01-01

    A general concept of potential field is introduced. The potential field that one puts in correspondence with dark matter, has fundamental geometrical interpretation (parallel transport) and has intrinsically inherent local symmetry. The equations of dark matter field are derived that are invariant with respect to the local transformations. It is shown how to reduce these equations to the Maxwell equations. Thus, the dark matter field may be considered as generalized lectromagnetic field and a simple solution of the old problem is given to connect electromagnetic field with geometrical properties of the physical manifold itself. It is shown that gauge fixing renders generalized electromagnetic field effectively massive while the Maxwell electromagnetic field remains massless. To learn more about interactions between matter and dark matter on the microscopical level (and to recognize the fundamental role of internal symmetry) the general covariant Dirac equation is derived in the Minkowski space--time which des...

  6. Impact of electromagnetic field on the pathogenicity of selected ...

    African Journals Online (AJOL)

    Rhipicephalus decoloratus) to variable intensities of electromagnetic field for different periods of time was examined on their pathogenicity on tick. Some bacterial isolates from the macerate of tick cadavers were used in the infection of healthy engorged ...

  7. Effect of Mobile Phone Radiofrequency Electromagnetic Fields on ...

    African Journals Online (AJOL)

    olayemitoyin

    Summary: Since cell phones emit radiofrequency electromagnetic fields (EMFs), this study tested the hypothesis that cell phones placed ... mobile phones on autonomic modulation of the heart. ..... Electrocardiogram and Its Technology. J. Am.

  8. Influence of storm electromagnetic field on the aircraft crew

    Directory of Open Access Journals (Sweden)

    Э. Г. Азнакаев

    2000-12-01

    Full Text Available Considered is the biophysical influence of alternative electromagnetic fields, caused by electrical discharges in atmosphere. Analyzed are conditions which may provoke inadequate actions and errors of the crew in airplane flight control

  9. The power and beauty of electromagnetic fields

    CERN Document Server

    Morgenthaler, Frederic R

    2011-01-01

    Unique, multi-level textbook is adaptable to introductory, intermediate, and advanced levels This revolutionary textbook takes a unique approach to electromagnetic theory, comparing both conventional and modern theories. It explores both the Maxwell-Poynting representation as well as the Alternate representation, which the author demonstrates is generally simpler and more suitable for analyzing modern electromagnetic environments. Throughout the text, students and researchers have the opportunity to examine both of these theories and discover how each one can be applied to solve problems.

  10. The Electromagnetic Field of Elementary Time-Dependent Toroidal Sources

    International Nuclear Information System (INIS)

    Afanas'ev, G.N.; Stepanovskij, Yu.P.

    1994-01-01

    The radiation field of toroidal-like time-dependent current configurations is investigated. Time-dependent charge-current sources are found outside which the electromagnetic strengths disappear but the potentials survive. This can be used to carry out time-dependent Aharonov-Bohm-like experiments and the information transfer. Using the Neumann-Helmholtz parametrization of the current density we present the time-dependent electromagnetic field in a form convenient for applications. 17 refs

  11. Rydberg atoms ionization by microwave field and electromagnetic pulses

    International Nuclear Information System (INIS)

    Kaulakys, B.; Vilutis, G.

    1995-01-01

    A simple theory of the Rydberg atoms ionization by electromagnetic pulses and microwave field is presented. The analysis is based on the scale transformation which reduces the number of parameters and reveals the functional dependencies of the processes. It is shown that the observed ionization of Rydberg atoms by subpicosecond electromagnetic pulses scale classically. The threshold electric field required to ionise a Rydberg state may be simply evaluated in the photonic basis approach for the quantum dynamics or from the multiphoton ionization theory

  12. Experimental research on electromagnetic radiation in inductive energy storage accelerator

    International Nuclear Information System (INIS)

    Zhong Jianzhong; Liu Lie; Li Limin; Wen Jianchun

    2008-01-01

    There exists strong electromagnetic radiation in inductive energy storage accelerators. In can destroy a measuring device at a distance. By repeated experiments, we found that it is a wide-spectrum electromagnetic wave with a main frequency of 75 MHz. The effector such as coaxial transmission line is effected strongly in short distance. The current in the coaxial transmission line can be measured in Rogowski coils. The strength of field in it is about 500 V/m and the peak current is 217 mA. The radiation source may be LC oscillating or electric exploding opening switch. Through the experimental research, we think it probably may be caused by the LC oscillating in the circuit when the switches conduct. And its strength is correlated to current change ratio. The change rate in secondary circuit is stronger than in primary circuit. So the radiation generated in secondary circuit is stronger than in primary circuit. It may be a reference for further research in inductive energy storage accelerators and shielding electromagnetic disturbing. (authors)

  13. Electromagnetic-implosion generation of pulsed high energy density plasma

    International Nuclear Information System (INIS)

    Baker, W.L.; Broderick, N.F.; Degnan, J.H.; Hussey, T.W.; Kiuttu, G.F.; Kloc, D.A.; Reinovsky, R.E.

    1983-01-01

    This chapter reports on the experimental and theoretical investigation of the generation of pulsed high-energy-density plasmas by electromagnetic implosion of cylindrical foils (i.e., imploding liners or hollow Z-pinches) at the Air Force Weapons Laboratory. Presents a comparison of experimental data with one-dimensional MHD and two-dimensional calculations. Points out that the study is distinct from other imploding liner efforts in that the approach is to produce a hot, dense plasma from the imploded liner itself, rather than to compress a magnetic-field-performed plasma mixture. The goal is to produce an intense laboratory pulsed X-ray source

  14. Numerical Analysis of Electromagnetic Fields in Multiscale Model

    International Nuclear Information System (INIS)

    Ma Ji; Fang Guang-You; Ji Yi-Cai

    2015-01-01

    Modeling technique for electromagnetic fields excited by antennas is an important topic in computational electromagnetics, which is concerned with the numerical solution of Maxwell's equations. In this paper, a novel hybrid technique that combines method of moments (MoM) with finite-difference time-domain (FDTD) method is presented to handle the problem. This approach employed Huygen's principle to realize the hybridization of the two classical numerical algorithms. For wideband electromagnetic data, the interpolation scheme is used in the MoM based on the dyadic Green's function. On the other hand, with the help of equivalence principle, the scattered electric and magnetic fields on the Huygen's surface calculated by MoM are taken as the sources for FDTD. Therefore, the electromagnetic fields in the environment can be obtained by employing finite-difference time-domain method. Finally, numerical results show the validity of the proposed technique by analyzing two canonical samples. (paper)

  15. Electromagnetic Vibration Energy Harvesting for Railway Applications

    Directory of Open Access Journals (Sweden)

    Bradai S.

    2018-01-01

    Full Text Available Safe localization of trains via GPS and wireless sensors is essential for railway traffic supervision. Especially for freight trains and because normally no power source is available on the wagons, special solutions for energy supply have to be developed based on energy harvesting techniques. Since vibration is available in this case, it provides an interesting source of energy. Nevertheless, in order to have an efficient design of the harvesting system, the existing vibration needs to be investigated. In this paper, we focus on the characterization of vibration parameters in railway application. We propose an electromagnetic vibration converter especially developed to this application. Vibration profiles from a train traveling between two German cities were measured using a data acquisition system installed on the train’s wagon. Results show that the measured profiles present multiple frequency signals in the range of 10 to 50 Hz and an acceleration of up to 2 g. A prototype for a vibration converter is designed taking into account the real vibration parameters, robustness and integrability requirements. It is based on a moving coil attached to a mechanical spring. For the experimental emulation of the train vibrations, a shaker is used as an external artificial vibration source controlled by a laser sensor in feedback. A maximum voltage of 1.7 V peak to peak which corresponds to a maximum of 10 mW output power where the applied excitation frequency is close to the resonant frequency of the converter which corresponds to 27 Hz.

  16. Pair production of arbitrary spin particles by electromagnetic fields

    International Nuclear Information System (INIS)

    Kruglov, S.I.

    2006-01-01

    The exact solutions of the wave equation for arbitrary spin particles in the field of the soliton-like electric impulse were obtained. The differential probability of pair production of particles by electromagnetic fields has been evaluated on the basis of the exact solutions. As a particular case, the particle pair production in the constant and uniform electric field were studied

  17. Study of Electromagnetic Fields on Cellular Systems Study of Electromagnetic Fields on Cellular Systems

    Directory of Open Access Journals (Sweden)

    Sergio Solorio-Meza

    2012-02-01

    Full Text Available Durante las últimas décadas, el interés por explicar el efecto de la radiación no ionizante, como es el caso de los campos electromagnéticos (CEM sobre sistemas celulares ha aumentado considerablemente. En este artículo se describe la interacción que existe entre los CEM y sistemas biológicos. Se discute el efecto de la estimulación electromagnética a diferentes frecuencias e intensidades en cultivos celulares. Resultados preliminares al estimular células de neuroblastomas SK-NSH con campos electromagnéticos de extra baja frecuencia (CEM-EBF, CEM que van del rango de 3 a 30 Hz, indican que se induce un estrés celularque se refleja en variaciones en la expresión de proteínas respecto al grupo de células no estimuladas. En particular, la expresión de las proteínas muestra que los CEM-EBF producen cambios en las proteínas presentes en condiciones normales o basales en las células, es decir, aparecen nuevas proteínas o existe un aumento en la cantidad de ellas.In the last decades the interest to study the effect of non-ionizing radiation, such as the electromagnetic fields (EMF on cellular systems has increased. In this article the interaction between EMF and biological systems is described. An analysis of the effect of the electromagnetic stimulation at different frequencies and intensities on cell cultures is performed. Preliminary results show that the stimulation with extremely low frequency electromagnetic fields (ELF-EMF, EMF from 3 to 30 Hz, on the cellular line of neuroblastomaSK-NSH induces cellular stress. This is reflected by a variation in the proteins expression in comparison with the group of cells no stimulated. In particular, the proteins expression shows that the ELF-EMF produce changes in the current proteins in normal or basal conditionsin the cells, that is, new proteins appear or there is evidence of an increasing in theamount of them.

  18. [The influence of electromagnetic fields on flora and fauna].

    Science.gov (United States)

    Rochalska, Małgorzata

    2009-01-01

    This paper presents the influence of natural and artificial electromagnetic fields (EMF) on fauna and flora. The mechanisms of Earth's magnetic field detection and the use of this skill by migratory animals to faultlessly reach the destination of their travel are discussed, as well as the positive effects of electric and magnetic fields on plants relative to their physiology, yielding and health. EMF influence on social insects and animal organisms, including possible DNA damages and DNA repair systems, is presented. The influence of high frequency electromagnetic fields on birds nesting is also discussed.

  19. Quantizing the electromagnetic field near two-sided semitransparent mirrors

    Science.gov (United States)

    Furtak-Wells, Nicholas; Clark, Lewis A.; Purdy, Robert; Beige, Almut

    2018-04-01

    This paper models light scattering through flat surfaces with finite transmission, reflection, and absorption rates, with wave packets approaching the mirror from both sides. While using the same notion of photons as in free space, our model also accounts for the presence of mirror images and the possible exchange of energy between the electromagnetic field and the mirror surface. To test our model, we derive the spontaneous decay rate and the level shift of an atom in front of a semitransparent mirror as a function of its transmission and reflection rates. When considering limiting cases and using standard approximations, our approach reproduces well-known results but it also paves the way for the modeling of more complex scenarios.

  20. Electromagnetic field theory. Solely theories with plasma in focus

    International Nuclear Information System (INIS)

    Stenstrom, L.

    1979-01-01

    The Institute of Electromagnetic Field Theory at Chalmers Technical University is concerned with purely theoretical work on plasma physics for nuclear fusion. The team concerned is looking at nonlinear effects in the plasma energy exchange mechanism. Both inertia restricted and magnetically enclosed plasma are considered. Analytic and computer methods are used upon the model equations of the plasma. The Institute has associations with Euratom and with work in Maryland and in Grenoble. Work on particle paths is of interst. It also is associated with the construction at Sundsvik of an accelerator to give zero keV negative ions. A problem is to find staff of a sufficiently high quality for such complex work. The difficulties are not economic, but mainly that the desired practical results appear to be so far into the future. (G.P.)

  1. Probing intergalactic magnetic fields with simulations of electromagnetic cascades

    Energy Technology Data Exchange (ETDEWEB)

    Alves Batista, Rafael [Oxford Univ. (United Kingdom). Dept. of Physics and Astrophysics; Saveliev, Andrey [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Russian Academy of Sciences, Moscow (Russian Federation). Keldysh Inst. of Applied Mathematics; Sigl, Guenter [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Vachaspati, Tanmay [Arizona State Univ., Tempe, AZ (United States). Dept. of Physics

    2016-12-15

    We determine the effect of intergalactic magnetic fields on the distribution of high energy gamma rays by performing three-dimensional Monte Carlo simulations of the development of gamma-ray-induced electromagnetic cascades in the magnetized intergalactic medium. We employ the so-called ''Large Sphere Observer'' method to efficiently simulate blazar gamma ray halos. We study magnetic fields with a Batchelor spectrum and with maximal left- and right-handed helicities. We also consider the case of sources whose jets are tilted with respect to the line of sight. We verify the formation of extended gamma ray halos around the source direction, and observe spiral-like patterns if the magnetic field is helical. We apply the Q-statistics to the simulated halos to extract their spiral nature and also propose an alternative method, the S-statistics. Both methods provide a quantative way to infer the helicity of the intervening magnetic fields from the morphology of individual blazar halos for magnetic field strengths B>or similar 10{sup -15} G and magnetic coherence lengths L{sub c}>or similar 100 Mpc. We show that the S-statistics has a better performance than the Q-statistics when assessing magnetic helicity from the simulated halos.

  2. Probing intergalactic magnetic fields with simulations of electromagnetic cascades

    International Nuclear Information System (INIS)

    Alves Batista, Rafael; Saveliev, Andrey; Russian Academy of Sciences, Moscow; Sigl, Guenter; Vachaspati, Tanmay

    2016-12-01

    We determine the effect of intergalactic magnetic fields on the distribution of high energy gamma rays by performing three-dimensional Monte Carlo simulations of the development of gamma-ray-induced electromagnetic cascades in the magnetized intergalactic medium. We employ the so-called ''Large Sphere Observer'' method to efficiently simulate blazar gamma ray halos. We study magnetic fields with a Batchelor spectrum and with maximal left- and right-handed helicities. We also consider the case of sources whose jets are tilted with respect to the line of sight. We verify the formation of extended gamma ray halos around the source direction, and observe spiral-like patterns if the magnetic field is helical. We apply the Q-statistics to the simulated halos to extract their spiral nature and also propose an alternative method, the S-statistics. Both methods provide a quantative way to infer the helicity of the intervening magnetic fields from the morphology of individual blazar halos for magnetic field strengths B>or similar 10"-"1"5 G and magnetic coherence lengths L_c>or similar 100 Mpc. We show that the S-statistics has a better performance than the Q-statistics when assessing magnetic helicity from the simulated halos.

  3. Electromagnetic waves in optical fibres in a magnetic field

    International Nuclear Information System (INIS)

    Gorelik, V S; Burdanova, M G

    2016-01-01

    A new method is reported of recording the secondary radiation of luminescent substances based on the use of capillary fibres of great length. Theoretical analysis of the dispersion curves of electromagnetic radiation in capillary fibres doped with erbium ions Er 3+ has been established. The Lorentz model is used for describing the dispersion properties of electromagnetic waves in a homogeneous medium doped with rare-earth ions. The dispersion dependencies of polariton and axion–polariton waves in erbium nitrate hydrate are determined on the basis of the model of the interaction between electromagnetic waves and the resonance electronic states of erbium ions in the absence and presence of a magnetic field. (paper)

  4. Biological effects from electromagnetic fields: Research progress and exposure measurements

    International Nuclear Information System (INIS)

    Mauro, F.; Lovisolo, G.A.; Raganella, L.

    1992-01-01

    Although it is commonly accepted that exposure to high levels of electromagnetic, micro- and radiofrequency waves produces harmful effects to the health of man, the formulation of exposure limits is still an open process and dependent upon the evolving level of knowledge in this field. This paper surveys the current level of knowledge gained through 'in vitro' and 'in vivo' radiological and epidemiological studies on different types of electromagnetic radiation derived effects - chromosomal, mutagenic, carcinogenic. It then reviews efforts by international organizations, e. g., the International Radiation Protection Association, to establish exposure limits for radiofrequency electromagnetic fields. Brief notes are given on the electromagnetic radiation monitoring campaign being performed by public health authorities in the Lazio Region of Italy

  5. Poynting Theorem, Relativistic Transformation of Total Energy-Momentum and Electromagnetic Energy-Momentum Tensor

    Science.gov (United States)

    Kholmetskii, Alexander; Missevitch, Oleg; Yarman, Tolga

    2016-02-01

    We address to the Poynting theorem for the bound (velocity-dependent) electromagnetic field, and demonstrate that the standard expressions for the electromagnetic energy flux and related field momentum, in general, come into the contradiction with the relativistic transformation of four-vector of total energy-momentum. We show that this inconsistency stems from the incorrect application of Poynting theorem to a system of discrete point-like charges, when the terms of self-interaction in the product {\\varvec{j}} \\cdot {\\varvec{E}} (where the current density {\\varvec{j}} and bound electric field {\\varvec{E}} are generated by the same source charge) are exogenously omitted. Implementing a transformation of the Poynting theorem to the form, where the terms of self-interaction are eliminated via Maxwell equations and vector calculus in a mathematically rigorous way (Kholmetskii et al., Phys Scr 83:055406, 2011), we obtained a novel expression for field momentum, which is fully compatible with the Lorentz transformation for total energy-momentum. The results obtained are discussed along with the novel expression for the electromagnetic energy-momentum tensor.

  6. Electromagnetic projectile acceleration utilizing distributed energy sources

    International Nuclear Information System (INIS)

    Parker, J.V.

    1982-01-01

    Circuit equations are derived for an electromagnetic projectile accelerator (railgun) powered by a large number of capacitive discharge circuits distributed along its length. The circuit equations are put into dimensionless form and the parameters governing the solutions derived. After specializing the equations to constant spacing between circuits, the case of lossless rails and negligible drag is analyzed to show that the electrical to kinetic energy transfer efficiency is equal to sigma/2, where sigma = 2mS/Lq 2 0 and m is the projectile mass, S the distance between discharge circuit, Lthe rail inductance per unit length, and q 0 the charge on the first stage capacitor. For sigma = 2 complete transfer of electrical to kinetic energy is predicted while for sigma>2 the projective-discharge circuit system is unstable. Numerical solutions are presented for both lossless rails and for finite rail resistance. When rail resistance is included, >70% transfer is calculated for accelerators of arbitrary length. The problem of projectile startup is considered and a simple modification of the first two stages is described which provides proper startup. Finally, the results of the numerical solutions are applied to a practical railgun design. A research railgun designed for repeated operation at 50 km/sec is described. It would have an overall length of 77 m, an electrical efficiency of 81%, a stored energy per stage of 105 kJ, and a charge transfer of <50 C per stage. A railgun of this design appears to be practicable with current pulsed power technology

  7. Suppression and control of leakage field in electromagnetic helical microwiggler

    Energy Technology Data Exchange (ETDEWEB)

    Ohigashi, N. [Kansai Univ., Osaka (Japan); Tsunawaki, Y. [Osaka Sangyo Univ. (Japan); Imasaki, K. [Institute for Laser Technology, Osaka (Japan)] [and others

    1995-12-31

    Shortening the period of electromagnetic wiggler introduces both the radical increase of the leakage field and the decrease of the field in the gap region. The leakage field is severer problem in planar electromagnetic wiggler than in helical wiggler. Hence, in order to develop a short period electromagnetic wiggler, we have adopted {open_quotes}three poles per period{close_quotes} type electromagnetic helical microwiggler. In this work, we inserted the permanent magnet (PM) blocks with specific magnetized directions in the space between magnetic poles, for suppressing the leakage field flowing out from a pole face to the neighboring pole face. These PM-blocks must have higher intrinsic coersive force than saturation field of pole material. The gap field due to each pole is adjustable by controlling the leakage fields, that is, controlling the position of each iron screw set in each retainer fixing the PM-blocks. At present time, a test wiggler with period 7.8mm, periodical number 10 and gap length 4.6mm has been manufactured. Because the ratio of PM-block aperture to gap length is important parameter to suppress the leakage field, the parameter has been surveyed experimentally for PM-blocks with several dimensions of aperture. The field strength of 3-5kG (K=0.2-0.4) would be expected in the wiggler.

  8. Electromagnetic Lead Screw for Potential Wave Energy Application

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Wu, Weimin

    2014-01-01

    This paper presents a new type electromagnetic lead screw (EMLS) intended for wave energy application. Similar to the mechanical lead screw, this electromagnetic version can transfer slow linear motion to high-rotational motion, offering gearing effects. Compared with the existing pure magnetic...

  9. Multipole interactions of charged particles with the electromagnetic field

    International Nuclear Information System (INIS)

    Burzynski, A.

    1982-01-01

    The full multipole expansion for the lagrangian and hamiltonian of a system of point charges interacting with the electromagnetic field is studied in detail. Both classical and quantum theory are described for external and dynamical fields separately. One improvement with respect to the known Fiutak's paper is made. (author)

  10. The U(1) Higgs model in an external electromagnetic field

    International Nuclear Information System (INIS)

    Damgaard, P.H.; Heller, U.M.

    1988-01-01

    An external electromagnetic field is coupled to the lattice-regularized U(1) Higgs model. We study the phase diagram of this model by both analytical and numerical techniques for different values of the external field strength tensor. The results are compared with expectations based on the analogy with superconducting systems, as described by the phenomenological Ginzburg-Landau theory. (orig.)

  11. Electromagnetic processes in strong crystalline fields

    CERN Document Server

    Uggerhoj, U I; Esberg, J; Knudsen, H; Lund, M; Møller, S P; Sørensen, A H; Thomsen, A H; Uggerhøj, U I; Geissel, H; Scheidenberger, C; Weick, H; Winfield, J; Sona, P; Connell S; Ballestrero, S; Ketel, T; Dizdar, A; Mangiarotti, A

    2009-01-01

    As an addendum to the NA63 proposal cite{Ande05}, we propose to measure 1) the Landau-Pomeranchuk-Migdal (LPM) effect in low-$Z$ targets, 2) Magnetic suppression of incoherent bremsstrahlung resulting from exposure to an external field during the emission event, and 3) the bremsstrahlung emission from relativistic ($gamma=170$), fully stripped Pb nuclei penetrating various amorphous targets. Concerning the LPM effect, both the 'traditional' Migdal approach and the modern treatment by Baier and Katkov display inaccuracies, i.e. a possible lack of applicability in low-$Z$ targets. Moreover, the LPM effect has been shown to have a significant impact on giant air showers for energies in the EeV range - evidently processes in a low-$Z$ material. A measurement of magnetic suppression is demanding in terms of necessary accuracy (an expected $lesssim$15% effect), but would prove the existence of a basic interplay between coherent and incoherent processes, also believed to be significant in beamstrahlung emission. For...

  12. Biological effects of electromagnetic fields and recently updated safety guidelines for strong static magnetic fields

    International Nuclear Information System (INIS)

    Yamaguchi-Sekino, Sachiko; Sekino, Masaki; Ueno, Shoogo

    2011-01-01

    Humans are exposed daily to artificial and naturally occurring magnetic fields that originate from many different sources. We review recent studies that examine the biological effects of and medical applications involving electromagnetic fields, review the properties of static and pulsed electromagnetic fields that affect biological systems, describe the use of a pulsed electromagnetic field in combination with an anticancer agent as an example of a medical application that incorporates an electromagnetic field, and discuss the recently updated safety guidelines for static electromagnetic fields. The most notable modifications to the 2009 International Commission on Non-Ionizing Radiation Protection guidelines are the increased exposure limits, especially for those who work with or near electromagnetic fields (occupational exposure limits). The recommended increases in exposure were determined using recent scientific evidence obtained from animal and human studies. Several studies since the 1994 publication of the guidelines have examined the effects on humans after exposure to high static electromagnetic fields (up to 9.4 tesla), but additional research is needed to ascertain further the safety of strong electromagnetic fields. (author)

  13. Current Understanding of the Health Effects of Electromagnetic Fields.

    Science.gov (United States)

    Miah, Tayaba; Kamat, Deepak

    2017-04-01

    There has been an exponential increase in the use of electronic devices over the past few decades. This has led to increased exposure to electromagnetic fields (EMF). Electric fields result from differences in voltage, whereas magnetic fields result from the flow of electric current. Higher-frequency waves of EMF have more energy than lower-frequency waves, and thus generally tend to be more harmful. An EMF activates cellular stress response and also causes breaks in DNA strands. There are many methodological barriers to effectively measuring the associations of EMF and childhood cancers. The consensus from multiple studies is that there is no causal role of extremely low-frequency EMFs in childhood cancers, including brain cancer. A recent study showed a link between EMF radiation and the development of malignant tumors in rats. In light of that study, the American Academy of Pediatrics set out new recommendations to decrease the adverse effects of cellphone exposure on children. [Pediatr Ann. 2017;46(4):e172-e174.]. Copyright 2017, SLACK Incorporated.

  14. Modeling microwave electromagnetic field absorption in muscle tissues

    Science.gov (United States)

    Felbacq, D.; Clerjon, S.; Damez, J. L.; Zolla, F.

    2002-07-01

    Absorption of electromagnetic energy in human tissues is an important issue with respect to the safety of low-level exposure. Simulation is a way to a better understanding of electromagnetic dosimetry. This letter presents a comparison between results obtained from a numerical simulation and experimental data of absorbed energy by a muscle. Simulation was done using a bidimensional double-scale homogenization scheme leading to the effective permittivity tensor. Experimental measurements were performed at 10 GHz on bovine muscle, 30 hours after slaughter, thanks to the open-ended rectangular waveguide method. Results show a good agreement between measurements and simulated data.

  15. Electromagnetic Vibration Energy Harvesting Devices Architectures, Design, Modeling and Optimization

    CERN Document Server

    Spreemann, Dirk

    2012-01-01

    Electromagnetic vibration transducers are seen as an effective way of harvesting ambient energy for the supply of sensor monitoring systems. Different electromagnetic coupling architectures have been employed but no comprehensive comparison with respect to their output performance has been carried out up to now. Electromagnetic Vibration Energy Harvesting Devices introduces an optimization approach which is applied to determine optimal dimensions of the components (magnet, coil and back iron). Eight different commonly applied coupling architectures are investigated. The results show that correct dimensions are of great significance for maximizing the efficiency of the energy conversion. A comparison yields the architectures with the best output performance capability which should be preferably employed in applications. A prototype development is used to demonstrate how the optimization calculations can be integrated into the design–flow. Electromagnetic Vibration Energy Harvesting Devices targets the design...

  16. A broadband electromagnetic energy harvester with a coupled bistable structure

    OpenAIRE

    Zhu, Dibin; Beeby, Steve

    2013-01-01

    This paper investigates a broadband electromagnetic energy harvester with a coupled bistable structure. Both analytical model and experimental results showed that the coupled bistable structure requires lower excitation force to trigger bistable operation than conventional bistable structures. A compact electromagnetic vibration energy harvester with a coupled bistable structure was implemented and tested. It was excited under white noise vibrations. Experimental results showed that the coupl...

  17. Particle Production in Strong Electromagnetic Fields in Relativistic Heavy-Ion Collisions

    Directory of Open Access Journals (Sweden)

    Kirill Tuchin

    2013-01-01

    Full Text Available I review the origin and properties of electromagnetic fields produced in heavy-ion collisions. The field strength immediately after a collision is proportional to the collision energy and reaches ~mπ2 at RHIC and ~10mπ2 at LHC. I demonstrate by explicit analytical calculation that after dropping by about one-two orders of magnitude during the first fm/c of plasma expansion, it freezes out and lasts for as long as quark-gluon plasma lives as a consequence of finite electrical conductivity of the plasma. Magnetic field breaks spherical symmetry in the direction perpendicular to the reaction plane, and therefore all kinetic coefficients are anisotropic. I examine viscosity of QGP and show that magnetic field induces azimuthal anisotropy on plasma flow even in spherically symmetric geometry. Very strong electromagnetic field has an important impact on particle production. I discuss the problem of energy loss and polarization of fast fermions due to synchrotron radiation, consider photon decay induced by magnetic field, elucidate J/ψ dissociation via Lorentz ionization mechanism, and examine electromagnetic radiation by plasma. I conclude that all processes in QGP are affected by strong electromagnetic field and call for experimental investigation.

  18. Multiphoton ionization of the hydrogen atom by a circularly polarized electromagnetic field

    International Nuclear Information System (INIS)

    Prepelitsa, O.B.

    1999-01-01

    This paper examines the multiphoton ionization of the ground state of the hydrogen atom in the field of a circularly polarized intense electromagnetic wave. To describe the states of photoelectrons, quasiclassical wave functions are introduced that partially allow for the effect of an intense electromagnetic wave and that of the Coulomb potential. Expressions are derived for the angular and energy distributions of photoelectrons with energies much lower than the ionization potential of an unperturbed atom. It is found that, due to allowance for the Coulomb potential in the wave function of the final electron states, the transition probability near the ionization threshold tends to a finite value. In addition, the well-known selection rules for multiphoton transitions in a circularly polarized electromagnetic field are derived in a natural way. Finally, the results are compared with those obtained in the Keldysh-Faisal-Reiss approximation

  19. Method for imaging with low frequency electromagnetic fields

    Science.gov (United States)

    Lee, Ki H.; Xie, Gan Q.

    1994-01-01

    A method for imaging with low frequency electromagnetic fields, and for interpreting the electromagnetic data using ray tomography, in order to determine the earth conductivity with high accuracy and resolution. The imaging method includes the steps of placing one or more transmitters, at various positions in a plurality of transmitter holes, and placing a plurality of receivers in a plurality of receiver holes. The transmitters generate electromagnetic signals which diffuse through a medium, such as earth, toward the receivers. The measured diffusion field data H is then transformed into wavefield data U. The traveltimes corresponding to the wavefield data U, are then obtained, by charting the wavefield data U, using a different regularization parameter .alpha. for each transform. The desired property of the medium, such as conductivity, is then derived from the velocity, which in turn is constructed from the wavefield data U using ray tomography.

  20. Calculation of magnetic field and electromagnetic forces in MHD superconducting magnets

    International Nuclear Information System (INIS)

    Martinelli, G.; Morini, A.; Moisio, M.F.

    1992-01-01

    The realization of a superconducting prototype magnet for MHD energy conversion is under development in Italy. Electromechanical industries and University research groups are involved in the project. The paper deals with analytical methods developed at the Department of Electrical Engineering of Padova University for calculating magnetic field and electromagnetic forces in MHD superconducting magnets and utilized in the preliminary design of the prototype

  1. Occupational exposure to electromagnetic fields in the Polish Armed Forces.

    Science.gov (United States)

    Sobiech, Jaromir; Kieliszek, Jarosław; Puta, Robert; Bartczak, Dagmara; Stankiewicz, Wanda

    2017-06-19

    Standard devices used by military personnel that may pose electromagnetic hazard include: radars, missile systems, radio navigation systems and radio transceivers. The aim of this study has been to evaluate the exposure of military personnel to electromagnetic fields. Occupational exposure to electromagnetic fields was analyzed in the work environment of personnel of 204 devices divided into 5 groups (surface-to-air missile system radars, aircraft and helicopters, communication devices, surveillance and height finder radars, airport radars and radio navigation systems). Measurements were carried out at indicators, device terminals, radio panels, above vehicle seats, in vehicle hatches, by cabinets containing high power vacuum tubes and other transmitter components, by transmission lines, connectors, etc. Portable radios emit the electric field strength between 20-80 V/m close to a human head. The manpack radio operator's exposure is 60-120 V/m. Inside vehicles with high frequency/very high frequency (HF/VHF) band radios, the electric field strength is between 7-30 V/m and inside the radar cabin it ranges between 9-20 V/m. Most of the personnel on ships are not exposed to the electromagnetic field from their own radar systems but rather by accidental exposure from the radar systems of other ships. Operators of surface-to-air missile systems are exposed to the electric field strength between 7-15 V/m and the personnel of non-directional radio beacons - 100-150 V/m. In 57% of military devices Polish soldiers work in the occupational protection zones. In 35% of cases, soldiers work in intermediate and hazardous zones and in 22% - only in the intermediate zone. In 43% of devices, military personnel are not exposed to electromagnetic field. Int J Occup Med Environ Health 2017;30(4):565-577. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  2. Occupational exposure to electromagnetic fields in the Polish Armed Forces

    Directory of Open Access Journals (Sweden)

    Jarosław Kieliszek

    2017-08-01

    Full Text Available Objectives: Standard devices used by military personnel that may pose electromagnetic hazard include: radars, missile systems, radio navigation systems and radio transceivers. The aim of this study has been to evaluate the exposure of military personnel to electromagnetic fields. Material and Methods: Occupational exposure to electromagnetic fields was analyzed in the work environment of personnel of 204 devices divided into 5 groups (surface-to-air missile system radars, aircraft and helicopters, communication devices, surveillance and height finder radars, airport radars and radio navigation systems. Measurements were carried out at indicators, device terminals, radio panels, above vehicle seats, in vehicle hatches, by cabinets containing high power vacuum tubes and other transmitter components, by transmission lines, connectors, etc. Results: Portable radios emit the electric field strength between 20–80 V/m close to a human head. The manpack radio operator’s exposure is 60–120 V/m. Inside vehicles with high frequency/very high frequency (HF/VHF band radios, the electric field strength is between 7–30 V/m and inside the radar cabin it ranges between 9–20 V/m. Most of the personnel on ships are not exposed to the electromagnetic field from their own radar systems but rather by accidental exposure from the radar systems of other ships. Operators of surface-to-air missile systems are exposed to the electric field strength between 7–15 V/m and the personnel of non-directional radio beacons – 100–150 V/m. Conclusions: In 57% of military devices Polish soldiers work in the occupational protection zones. In 35% of cases, soldiers work in intermediate and hazardous zones and in 22% – only in the intermediate zone. In 43% of devices, military personnel are not exposed to electromagnetic field. Int J Occup Med Environ Health 2017;30(4:565–577

  3. Uniqueness of time-independent electromagnetic fields

    DEFF Research Database (Denmark)

    Karlsson, Per W.

    1974-01-01

    As a comment on a recent paper by Steele, a more general uniqueness theorem for time-independent fields is mentioned. ©1974 American Institute of Physics......As a comment on a recent paper by Steele, a more general uniqueness theorem for time-independent fields is mentioned. ©1974 American Institute of Physics...

  4. Energy and thermodynamic considerations involving electromagnetic zero-point radiation

    International Nuclear Information System (INIS)

    Cole, Daniel C.

    1999-01-01

    There has been recent speculation and controversy regarding whether electromagnetic zero-point radiation might be the next candidate in the progression of plentiful energy sources, ranging, for example, from hydrodynamic, chemical, and nuclear energy sources. Certainly, however, extracting energy from the vacuum seems counter intuitive to most people. Here, these ideas are clarified, drawing on simple and common examples. Known properties of electromagnetic zero-point energy are qualitatively discussed. An outlook on the success of utilizing this energy source is then discussed

  5. Vacuum in the presence of electromagnetic fields and rotating boundaries

    International Nuclear Information System (INIS)

    Manogue, C.A.

    1984-01-01

    Two investigations of the properties of the vacuum are made. The first is a reconsideration of the classic Klein paradox, particle creation due to the presence of very strong external electromagnetic potentials. Expectation values of the current, momentum, and number operators, each of which is a measure of particle creation, are calculated for both massive spin zero and massive spin one half fields. The relationship between super-radiance and pair creation is explained. A review of past work by other authors is included and common conceptual errors are pointed out. The second investigation concerns the rotation of the vacuum caused by the rotation of boundaries. Just as the presence of boundaries can create a change in the vacuum expectation value of the energy density (the Casimir effect), the rotation of such boundaries can create changes in the vacuum expectation value of the momentum density. Calculations of the Casimir effect are made for a massless scalar field confined to an infinitely long square box. The change in the vacuum expectation value of the momentum density is calculated if this same box is rotating around its long central axis. In contrast, it is shown that for an infinitely long circular cylinder there is no change in the momentum density

  6. Electromagnetic fields and Green functions in elliptical vacuum chambers

    CERN Document Server

    AUTHOR|(CDS)2084216; Biancacci, Nicolo; Migliorati, Mauro; Palumbo, Luigi; Vaccaro, Vittorio; CERN. Geneva. ATS Department

    2017-01-01

    In this paper, we discuss the electromagnetic interaction between a point charge travelling inside a waveguide of elliptical cross section, and the waveguide itself. By using a convenient expansion of the Mathieu functions, useful in particular for treating a variety of problems in applied mathematics and physics with elliptic geometry, we first obtain the longitudinal electromagnetic field of a point charge (Green function) in free space in terms of elliptical coordinates. This expression allows, then, to calculate the scattered field due to the boundary conditions in our geometry. By summing the contribution of the direct or primary field and the indirect field scattered by the boundary, after a careful choice of some expansion expressions, we derive a novel formula of the longitudinal electric field, in any transverse position of the elliptical cross section, generated by the charge moving along the longitudinal axis of the waveguide. The obtained expression is represented in a closed form, it can be diffe...

  7. A physically motivated quantization of the electromagnetic field

    International Nuclear Information System (INIS)

    Bennett, Robert; Barlow, Thomas M; Beige, Almut

    2016-01-01

    The notion that the electromagnetic field is quantized is usually inferred from observations such as the photoelectric effect and the black-body spectrum. However accounts of the quantization of this field are usually mathematically motivated and begin by introducing a vector potential, followed by the imposition of a gauge that allows the manipulation of the solutions of Maxwell’s equations into a form that is amenable for the machinery of canonical quantization. By contrast, here we quantize the electromagnetic field in a less mathematically and more physically motivated way. Starting from a direct description of what one sees in experiments, we show that the usual expressions of the electric and magnetic field observables follow from Heisenberg’s equation of motion. In our treatment, there is no need to invoke the vector potential in a specific gauge and we avoid the commonly used notion of a fictitious cavity that applies boundary conditions to the field. (paper)

  8. Electromagnetic field for an open magnetosphere

    International Nuclear Information System (INIS)

    Heikkila, W.J.

    1984-01-01

    The boundary-layer-dominated models of the earth EM field developed by Heikkila (1975, 1978, 1982, and 1983) and Heikkila et al. (1979) to account for deficiencies in the electric-field descriptions of quasi-steady-state magnetic-field-reconnection models (such as that of Cowley, 1980) are characterized, reviewing the arguments and indicating the most important implications. The mechanisms of boundary-layer formation and field direction reversal are explained and illustrated with diagrams, and it is inferred that boundary-layer phenomena rather than magnetic reconnection may be the cause of large-scale magnetospheric circulation, convection, plasma-sheet formation and sunward convection, and auroras, the boundary layer acting basically as a viscous process mediating solar-wind/magnetosphere interactions. 23 references

  9. The electromagnetic field for an open magnetosphere

    Science.gov (United States)

    Heikkila, W. J.

    1984-01-01

    The boundary-layer-dominated models of the earth EM field developed by Heikkila (1975, 1978, 1982, and 1983) and Heikkila et al. (1979) to account for deficiencies in the electric-field descriptions of quasi-steady-state magnetic-field-reconnection models (such as that of Cowley, 1980) are characterized, reviewing the arguments and indicating the most important implications. The mechanisms of boundary-layer formation and field direction reversal are explained and illustrated with diagrams, and it is inferred that boundary-layer phenomena rather than magnetic reconnection may be the cause of large-scale magnetospheric circulation, convection, plasma-sheet formation and sunward convection, and auroras, the boundary layer acting basically as a viscous process mediating solar-wind/magnetosphere interactions.

  10. Effects of extremely low frequency electromagnetic fields on growth ...

    African Journals Online (AJOL)

    Electromagnetic fields are an important environmental factor that can influence the growth and development of plants. Exposure to EMFs was performed by a locally designed EMF generator. Our investigations were focused on plants grown from wet pretreated seeds with 3 and 10 mT for a 4 h exposure time and compared ...

  11. Effect of Electromagnetic Fields on Transfer Processes in Heterogeneous Systems

    Czech Academy of Sciences Publication Activity Database

    Levdansky, V.V.; Kim, H. Y.; Kim, H. C.; Smolík, Jiří; Moravec, Pavel

    2001-01-01

    Roč. 44, č. 5 (2001), s. 1065-1071 ISSN 0017-9310 Institutional research plan: CEZ:AV0Z4072921 Keywords : electromagnetic field * transfer processes * heterogeneous system Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.240, year: 2001

  12. Electromagnetic fields of ionospheric point dipoles in the earthionosphere waveguide

    International Nuclear Information System (INIS)

    Rybachek, S.T.

    1985-01-01

    This paper addresses the problem of excitation of the spherical earth-anisotropic ionosphere waveguide by ionospheric dipole sources. The solution obtained is based on a generalized reciprocity theorem which provides a relationship to the problem of finding electromagnetic fields in the ionosphere created by sources located in the waveguide. Some results of the calculations are presented

  13. Generation of a Desired Three-Dimensional Electromagnetic Field

    DEFF Research Database (Denmark)

    2005-01-01

    The present invention relates to a method and a system for synthesizing a prescribed three-dimensional electromagnetic field based on generalized phase contrast imaging. Such a method and apparatus may be utilized in advanced optical micro and nano-manipulation, such as by provision of a multiple...

  14. The concept of free electromagnetic field in quantum domain

    OpenAIRE

    SHUMOVSKY, Alexander; MÜSTECAPLIOĞLU, Özgür

    1999-01-01

    By virtue of the consideration of polarization and phase properties of dipole radiation in the quantum domain, it is shown that the concept of free electromagnetic field should be considered as a quite risky approximation in the description of quantum fluctuations of some physical observables.

  15. Effect of Mobile Phone Radiofrequency Electromagnetic Fields on ...

    African Journals Online (AJOL)

    Summary: Since cell phones emit radiofrequency electromagnetic fields (EMFs), this study tested the hypothesis that cell phones placed near the heart may interfere with the electrical rhythm of the heart or affect the blood pressure. Following informed consent, eighteen randomly selected apparently healthy male volunteers ...

  16. Interaction of strong electromagnetic fields with atoms

    International Nuclear Information System (INIS)

    Brandi, H.S.; Davidovich, L.; Zagury, N.

    1982-06-01

    Several non-linear processes involvoing the interaction of atoms with strong laser fields are discussed, with particular emphasis on the ionization problem. Non-perturbative methods which have been proposed to tackle this problem are analysed, and shown to correspond to an expansion in the intra-atomic potential. The relation between tunneling and multiphoton absorption as ionization mechanisms, and the generalization of Einstein's photoelectric equation to the strong-field case are discussed. (Author) [pt

  17. Electromagnetic fields from mobile phone base station - variability analysis.

    Science.gov (United States)

    Bienkowski, Pawel; Zubrzak, Bartlomiej

    2015-09-01

    The article describes the character of electromagnetic field (EMF) in mobile phone base station (BS) surroundings and its variability in time with an emphasis on the measurement difficulties related to its pulse and multi-frequency nature. Work also presents long-term monitoring measurements performed recently in different locations in Poland - small city with dispersed building development and in major polish city - dense urban area. Authors tried to determine the trends in changing of EMF spectrum analyzing daily changes of measured EMF levels in those locations. Research was performed using selective electromagnetic meters and also EMF meter with spectrum analysis.

  18. Electromagnetically induced transparency with quantized fields in optocavity mechanics

    International Nuclear Information System (INIS)

    Huang Sumei; Agarwal, G. S.

    2011-01-01

    We report electromagnetically induced transparency (EIT) using quantized fields in optomechanical systems. The weak probe field is a narrowband squeezed field. We present a homodyne detection of EIT in the output quantum field. We find that the EIT dip exists even though the photon number in the squeezed vacuum is at the single-photon level. The EIT with quantized fields can be seen even at temperatures on the order of 100 mK, thus paving the way for using optomechanical systems as memory elements.

  19. Design of a high field uniformity electromagnet for Penning trap

    International Nuclear Information System (INIS)

    Itteera, Janvin; Singh, Kumud; Teotia, Vikas; Ukarde, Priti; Malhotra, Sanjay; Taly, Y.K.; Joshi, Manoj; Rao, Pushpa

    2013-01-01

    An ion trap (Penning trap) facility is being developed at BARC for spectroscopy studies. This requires the design of an iron core electromagnet capable of generating high magnetic fields (∼1.7T) at the centre of an 88 mm long air gap. This electromagnet provides the requisite dipole magnetic field which when superimposed on the electrostatic quadrupoles ensures a stable trapping of ions. To conduct high precision spectroscopy studies, we need to ensure a high degree of magnetic field uniformity ( 3 volume (Trap zone). Various pole shoe profiles were studied and modelled, FEM simulation of the same were conducted to compute the magnetic field intensity and field uniformity. Owing to the large air gap and requirement of high field intensity in the GFR, the exciting coils need to handle high current densities, which require water cooled systems. Double Pan-Cake coil design is selected for powering the magnet. Electrical, thermal and hydraulic designs of the coils are completed and a prototype double pancake coil was fabricated and tested for verifying the electrical and thermal parameter. The spatial field homogeneity is achieved by shimming the pole tip. Temporal stability of magnet requires a highly stable power supply for exciting the coils and its stability class is derived from FEM simulations. This paper discusses the electromagnetic design and development of the penning trap magnet being developed at BARC. (author)

  20. Electromagnetic field scattering by a triangular aperture.

    Science.gov (United States)

    Harrison, R E; Hyman, E

    1979-03-15

    The multiple Laplace transform has been applied to analysis and computation of scattering by a double triangular aperture. Results are obtained which match far-field intensity distributions observed in experiments. Arbitrary polarization components, as well as in-phase and quadrature-phase components, may be determined, in the transform domain, as a continuous function of distance from near to far-field for any orientation, aperture, and transformable waveform. Numerical results are obtained by application of numerical multiple inversions of the fully transformed solution.

  1. A broadband electromagnetic energy harvester with a coupled bistable structure

    International Nuclear Information System (INIS)

    Zhu, D; Beeby, S P

    2013-01-01

    This paper investigates a broadband electromagnetic energy harvester with a coupled bistable structure. Both analytical model and experimental results showed that the coupled bistable structure requires lower excitation force to trigger bistable operation than conventional bistable structures. A compact electromagnetic vibration energy harvester with a coupled bistable structure was implemented and tested. It was excited under white noise vibrations. Experimental results showed that the coupled bistable energy harvester can achieve bistable operation with lower excitation amplitude and generate more output power than both conventional bistable and linear energy harvesters under white noise excitation

  2. Design of Electric Field Sensors for Measurement of Electromagnetic Pulse

    Directory of Open Access Journals (Sweden)

    Hui ZHANG

    2014-01-01

    Full Text Available In this paper, a D-dot electric field sensor and a fiber-optic transmission electric field sensor are developed for measurement of electromagnetic pulse. The D-dot sensor is a differential model sensor without source and has a simple structure. The fiber-optic transmission sensor is in the type of small dipole antenna, which uses its outside shielding layer as a pair of antennas. Design of the sensor circuit and the test system are introduced in this paper. A calibration system for these pulsed field sensors is established and the test results verified the ability of the developed sensors for measurement of the standard electromagnetic pulse field (the half peak width is 25 ns and the rising time is 2.5 ns.

  3. CEBAF at higher energies and the kaon electromagnetic form factor

    Energy Technology Data Exchange (ETDEWEB)

    Baker, O.K.

    1994-04-01

    The electromagnetic production of strangeness, the physics of exciting systems having strangeness degrees of freedom (production of hadrons with one or more strange constituent quarks) using electromagnetic probes (real or virtual photons), is one of the frontier areas of research which will be investigated at the Continuous Electron Beam Accelerator Facility (CEBAF) when it becomes operational. CEBAF is expected to have an important impact upon this field of research using its specialized set of detection instruments and high quality electron beam. This paper focusses upon one aspect of the associated production of strangeness - the determination of the kaon electromagnetic form factor at high squared momentum transfers.

  4. Electromagnetic Drop Scale Scattering Modelling for Dynamic Statistical Rain Fields

    OpenAIRE

    Hipp, Susanne

    2015-01-01

    This work simulates the scattering of electromagnetic waves by a rain field. The calculations are performed for the individual drops and accumulate to a time signal dependent on the dynamic properties of the rain field. The simulations are based on the analytical Mie scattering model for spherical rain drops and the simulation software considers the rain characteristics drop size (including their distribution in rain), motion, and frequency and temperature dependent permittivity. The performe...

  5. Effects of RF low levels electromagnetic fields on Paramecium primaurelia

    International Nuclear Information System (INIS)

    Tofani, S.; Testa, B.; Agnesod, G.; Tartagbino, L.; Bonazzola, G.C.

    1988-01-01

    In the last years many studies have been performed to examine biological effects of prolonged exposure at electric field low levels. This great interest is linked to a specific interaction possibility, also related to the exposure length, between electromagnetic fields and biological systems without remarkable enhancement of organism's temperature. Hence the need to investigate in vitro the possible cellular regulation mechanisms involved in these interactions, varying physical exposure parameters

  6. Classical electromagnetic field theory in the presence of magnetic sources

    OpenAIRE

    Chen, Wen-Jun; Li, Kang; Naón, Carlos

    2001-01-01

    Using two new well defined 4-dimensional potential vectors, we formulate the classical Maxwell's field theory in a form which has manifest Lorentz covariance and SO(2) duality symmetry in the presence of magnetic sources. We set up a consistent Lagrangian for the theory. Then from the action principle we get both Maxwell's equation and the equation of motion of a dyon moving in the electro-magnetic field.

  7. Observation of asymmetric electromagnetic field profiles in chiral metamaterials

    Science.gov (United States)

    Hisamoto, Nobuyuki; Ueda, Tetsuya; Sawada, Kei; Tomita, Satoshi

    2018-02-01

    We experimentally observe asymmetric electromagnetic field profiles along two-dimensional chiral metamaterials. The asymmetric field profiles depending on the chirality and the operation frequency have been reproduced well by the numerical simulation. Around a chiral meta-atom, distribution of a Poynting vector is found to be shifted asymmetrically. These results are explained in terms of an analogy with the side-jump mechanism in the electronic anomalous Hall systems.

  8. Occupational exposure to electromagnetic fields and chronic diseases

    OpenAIRE

    Håkansson, Niclas

    2003-01-01

    This thesis consider two exposures from the electromagnetic spectrum extremely low-frequency magnetic fields (ELF MF) and ultraviolet (UV) radiation. ELF MF are the lowest and UV radiation ranges among the highest frequencies of non-ionizing radiation. The exposure prevalence of these fields is high in the general population. Most people are exposed daily to either or both types and potential health effects are of great concern. The aim of the thesis was to study occupationa...

  9. On Huygens' principle for Dirac operators associated to electromagnetic fields

    Directory of Open Access Journals (Sweden)

    CHALUB FABIO A.C.C.

    2001-01-01

    Full Text Available We study the behavior of massless Dirac particles, i.e., solutions of the Dirac equation with m = 0 in the presence of an electromagnetic field. Our main result (Theorem 1 is that for purely real or imaginary fields any Huygens type (in Hadamard's sense Dirac operators is equivalent to the free Dirac operator, equivalence given by changes of variables and multiplication (right and left by nonzero functions.

  10. Setting research strategy on electromagnetic-field pollution of Ecuador

    International Nuclear Information System (INIS)

    Becerra, C.A.

    1989-01-01

    General population and occupational groups are being exposed to electromagnetic field (EMF) nonionizing radiation that come from all electric or electronic equipment that work either with extremely low frequency (ELF) or radiofrequency (RF) fields. This preoccupation has generated research and regulation plans in some countries int he world, in order to set a clear configuration of bioeffects and other environmental implications derived from exposures to ELF/RF EMF

  11. Relativistic kinematics of the electromagnetic fields of a guided mode

    International Nuclear Information System (INIS)

    Rivlin, Lev A

    2000-01-01

    It is shown that during the observation of a wave in a waveguide from a comoving reference system travelling at a velocity equal to the group velocity of the wave, the wave propagation is halted and the electromagnetic energy contained in the waveguide proves to be stationary. The nonzero rest mass of the photons in the waveguide is equivalent to this rest energy and is identical with the rest mass measured in dynamic experiments. (laser applications and other topics in quantum electronics)

  12. Transient field behavior in an electromagnetic pulse from neutral-beam reflection

    International Nuclear Information System (INIS)

    Strobel, G.L.

    1990-01-01

    A neutral beam of electrons and positrons catches up to an electromagnetic pulse moving in a medium with refractive index n. The neutral beam is reflected and deposits some of its energy in a current region in the tail of the pulse. The location, size, and shape of the transient-induced electric fields in the current region are modeled using current densities from uniform averaged fields. The electric field in the current region is predicted to rise linearly with time, with a doubling time determined by the beam parameters and the initial local electromagnetic field. A coordinate frame comoving with the pulse is used to determine the extent of and conditions within the current region. In this comoving frame the Lorentz-transformed electric field is zero, but there is an enhanced Lorentz-transformed magnetic field. The extent of the current region is found from the radius of the semicircular charged-particle orbits in the comoving frame

  13. Occupational exposure to electromagnetic fields in physiotherapy departments

    International Nuclear Information System (INIS)

    Macca, I.; Scapellato, M. L.; Carrieri, M.; Di Bisceglie, A. P.; Saia, B.; Bartolucci, G. B.

    2008-01-01

    To assess occupational exposure to electromagnetic fields, 11 microwave (MW), 4 short-wave diathermy and 15 magneto therapy devices were analysed in eight physiotherapy departments. Measurements taken at consoles and environmental mapping showed values above European Directive 2004/40/EC and ACGIH exposure limits at ∼50 cm from MW applicators (2.45 GHz) and above the Directive magnetic field limit near the diathermy unit (27.12 MHz). Levels in front of MW therapy applicators decreased rapidly with distance and reduction in power; this may not always occur in work environments where nearby metal structures (chairs, couches, etc.) may reflect or perturb electromagnetic fields. Large differences in stray field intensities were found for various MW applicators. Measurements of power density strength around MW electrodes confirmed radiation fields between 30 deg. and 150 deg., with a peak at 90 deg., in front of the cylindrical applicator and maximum values between 30 deg. and 150 deg. over the whole range of 180 deg. for the rectangular parabolic applicator. Our results reveal that although most areas show substantially low levels of occupational exposure to electromagnetic fields in physiotherapy units, certain cases of over-occupational exposure limits do exist. (authors)

  14. Particles in spherical electromagnetic radiation fields

    International Nuclear Information System (INIS)

    Mitter, H.; Thaller, B.

    1984-03-01

    If the time-dependence of a Hamiltonian can be compensated by an appropriate symmetry transformation, the corresponding quantum mechanical problem can be reduced to an effectively stationary one. With this result we investigate the behavior of nonrelativistic particles in a spherical radiation field produced by a rotating source. Then the symmetry transformation corresponds to a rotation. We calculate the transition probabilities in Born approximation. The extension to problems involving an additional Coulomb potential is briefly discussed. (Author)

  15. DATA ACQUISITION AND ANALYSIS OF LOW FREQUENCY ELECTROMAGNETIC FIELD

    Directory of Open Access Journals (Sweden)

    PETRICA POPOV

    2016-06-01

    Full Text Available In recent years more and more studies have shown that, the low frequency field strength (particularly magnetic, 50 / 60Hz are a major risk factor; according to some specialists - even more important as the radiation field. As a result, the personnel serving equipment and facilities such as: electric generators, synchronous, the motors, the inverters or power transformers is subjected continually to intense fields, in their vicinity, with possible harmful effects in the long term by affecting metabolism cell, espectively, the biological mechanisms.Therefore, finding new methods and tools for measurement and analysis of low frequency electromagnetic fields may lead to improved standards for exposure limits of the human body.

  16. Radiation corrections to quantum processes in an intense electromagnetic field

    International Nuclear Information System (INIS)

    Narozhny, N.B.

    1979-01-01

    A derivation of an asymptotic expression for the mass correction of order α to the electron propagator in an intense electromagnetic field is presented. It is used for the calculation of radiation corrections to the electron and photon elastic scattering amplitudes in the α 3 approximation. All proper diagrams contributing to the amplitudes and containing the above-mentioned correction to the propagator were considered, but not those which include vertex corrections. It is shown that the expansion parameter of the perturbation theory of quantum electrodynamics in intense fields grows not more slowly than αchi/sup 1/3/ at least for the electron amplitude, where chi = [(eF/sub μν/p/sub ν/) 2 ] 12 /m 3 , p is a momentum of the electron, and F is the electromagnetic field tensor

  17. Electromagnetic fields mediate efficient cell reprogramming into a pluripotent state.

    Science.gov (United States)

    Baek, Soonbong; Quan, Xiaoyuan; Kim, Soochan; Lengner, Christopher; Park, Jung-Keug; Kim, Jongpil

    2014-10-28

    Life on Earth is constantly exposed to natural electromagnetic fields (EMFs), and it is generally accepted that EMFs may exert a variety of effects on biological systems. Particularly, extremely low-frequency electromagnetic fields (EL-EMFs) affect biological processes such as cell development and differentiation; however, the fundamental mechanisms by which EMFs influence these processes remain unclear. Here we show that EMF exposure induces epigenetic changes that promote efficient somatic cell reprogramming to pluripotency. These epigenetic changes resulted from EMF-induced activation of the histone lysine methyltransferase Mll2. Remarkably, an EMF-free system that eliminates Earth's naturally occurring magnetic field abrogates these epigenetic changes, resulting in a failure to undergo reprogramming. Therefore, our results reveal that EMF directly regulates dynamic epigenetic changes through Mll2, providing an efficient tool for epigenetic reprogramming including the acquisition of pluripotency.

  18. Resonant Electromagnetic Interaction in Low Energy Nuclear Reactions

    Science.gov (United States)

    Chubb, Scott

    2008-03-01

    Basic ideas about how resonant electromagnetic interaction (EMI) can take place in finite solids are reviewed. These ideas not only provide a basis for conventional, electron energy band theory (which explains charge and heat transport in solids), but they also explain how through finite size effects, it is possible to create many of the kinds of effects envisioned by Giuliano Preparata. The underlying formalism predicts that the orientation of the external fields in the SPAWAR protocolootnotetextKrivit, Steven B., New Energy Times, 2007, issue 21, item 10. http://newenergytimes.com/news/2007/NET21.htm^,ootnotetextSzpak, S.; Mosier-Boss, P.A.; Gordon, F.E. Further evidence of nuclear reactions in the Pd lattice: emission of charged particles. Naturwissenschaften 94,511(2007)..has direct bearing on the emission of high-energy particles. Resonant EMI also implies that nano-scale solids, of a particular size, provide an optimal environment for initiating Low Energy Nuclear Reactions (LENR) in the PdD system.

  19. Proton moire fringes for diagnosing electromagnetic fields in opaque materials and plasmas

    International Nuclear Information System (INIS)

    Mackinnon, A.J.; Patel, P.K.; Price, D.W.; Hicks, D.; Romagnani, L.; Borghesi, M.

    2003-01-01

    High contrast proton moire fringes have been obtained in a laser-produced proton beam. Moire fringes with modulation of 20%-30% were observed in protons with energies in the range of 4-7 MeV. Monte Carlo simulations with simple test fields showed that shifts in the moire fringes can be used to give quantitative information on the strength of transient electromagnetic fields inside plasmas and materials that are opaque to conventional probing methods

  20. Instrumentation for electromagnetic field generation in biological measurements

    International Nuclear Information System (INIS)

    Malaric, K.; Malaric, R.; Tkalec, M.; Lenicek, I.; Sala, A.

    2005-01-01

    Electromagnetic fields (EMFs) are part of everyday life in modern world. Extremely low-frequency EMFs (50 Hz) are produced by most electric home appliance, electric power transmission and distribution lines. For the last ten years mobile phones have been widely used all around the world. They operate on the EMF frequencies from 400 MHz to 1900 MHz. The effects of EMFs on living organisms have been the subject of debate and research for the last thirty years. The instrumentation for generation of EMFs have been designed at the Faculty of Electrical Engineering and Computing, Zagreb, and can be used for controlled exposure to different EMFs. To study the effect of extremely low-frequency EMF, duckweed (Lemna minor) - the model plant in biological measurement, test setup was made for magnetic field in Helmholtz coil and for electric field between two parallel circle electrodes. For the effect of mobile phones frequencies, test setup with exposition to the electromagnetic field was done with Gigahertz Transversal Electromagnetic Mode (GTEM) cell. The research confirmed that instrumentation used in these experiments is suitable for evaluation of biological effects of EMFs. The effect of different field strengths, exposure times and modulation can be tested with these instrumentation.(author)

  1. An integrated model for interaction of electromagnetic fields with biological systems

    International Nuclear Information System (INIS)

    Apollonio, F.; Liberti, M.; Cavagnaro, M.; D'Inzeo, G.; Tarricone, L.

    1999-01-01

    In this work is described a methodology for evaluation of interaction of high frequency electromagnetic field. Biological systems via connection of many macroscopic models. In particular the analysis of neuronal membrane exposed to electromagnetic fields [it

  2. TNB high tension overhead cables: is their electromagnetic field hazard real?

    International Nuclear Information System (INIS)

    Roha Tukimin; Mohd Yusof Mohd Ali; Mohamad Amirul Nizam

    2005-01-01

    Extremely low frequency electromagnetic fields (ELF, EMF) fall under the category of non-ionising radiation. We live in an electromagnetic environment generated by both natural (earths magnetic field, sunlight) and man-made. One of the man-made sources which produces significant electromagnetic fields (EMF) is the electric power supply system. In modern time, electricity has become an essential part of our lives. Electric power supply system, which includes generation, transmission and distribution of the electricity, produces extremely low frequency electromagnetic fields (ELF EMF) that travel along the overhead cables at 50 cycles per second (50 Hz).They are a form of energy that travels in space as electromagnetic waves. In spite of the fact that ELF EMF are very weak electromagnetic emission, they are believed to be hazardous to human health because of their ability to induce current and to initiate energy deposition in the body, which may eventually lead to increase in body temperature, behavioral changes and perhaps cancer in the long term. Due to their potential of causing such health hazard, several companies have approached and requested MINT to carry out surveys and safety assessments of their land properties, which are located close to the transmission lines. This paper highlights some of the works that had been carried out by MINT based on the requests received. They were performed based on international standard IEEE procedures protocols using properly calibrated portable ELF instruments. The results confirmed that ELF EMF did present at the survey sites but were very much lower than the permissible exposure limit recommended for members of public (1000 m Gauss / 5000 V/m). They were found to vary against measurements locations, which were strongly influenced by vertical and horizontal distances from the cables and by the presence of other objects like building and trees. (Author)

  3. Analysis of electromagnetic field of direct action solenoid valve with current changing

    International Nuclear Information System (INIS)

    Liu Qianfeng; Bo Hanliang; Qin Benke

    2009-01-01

    Control rod hydraulic drive mechanism(CRHDM) is a newly invented patent of Institute of Nuclear and New Energy Technology of Tsinghua University. The direct action solenoid valve is the key part of this technology, so the performance of the solenoid valve directly affects the function of the CRHDM. With the current and the air gap changing,the electromagnetic field of the direct action solenoid valve was analyzed using the ANSYS software,which was validated by the experiment. The result shows that the electromagnetic force of the solenoid valve increases with the current increasing or the gap between the two armatures decreasing. Further more, the working current was confirmed. (authors)

  4. Electromagnetic energy applied to and gained from lunar materials

    International Nuclear Information System (INIS)

    Meek, T.T.; Vaniman, D.T.; Blake, R.D.; Cocks, F.H.

    1986-01-01

    Electromagnetic energy may be useful in microwave frequencies for in-situ melting or sintering of lunar regolith. Simple configurations of magnetron or gyrotron tubes might be constructed for unique melting geometries. For energy production, lunar ilmenite has potential applications in photovoltaic devices. 11 refs., 11 figs

  5. Electromagnetic energy flow lines as possible paths of photons

    Energy Technology Data Exchange (ETDEWEB)

    Davidovic, M [Faculty of Civil Engineering, University of Belgrade, Bulevar Kralja Aleksandra 73, 11000 Belgrade (Serbia); Sanz, A S; Miret-Artes, S [Instituto de Fisica Fundamental, Consejo Superior de Investigaciones CientIficas, Serrano 123, 28006 Madrid (Spain); Arsenovic, D; Bozic, M [Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade (Serbia)], E-mail: milena@grf.bg.ac.yu, E-mail: asanz@imaff.cfmac.csic.es, E-mail: arsenovic@phy.bg.ac.yu, E-mail: bozic@phy.bg.ac.yu, E-mail: s.miret@imaff.cfmac.csic.es

    2009-07-15

    Motivated by recent experiments where interference patterns behind a grating are obtained by accumulating single photon events, we provide here an electromagnetic energy flow-line description to explain the emergence of such patterns. We find and discuss an analogy between the equation describing these energy flow lines and the equation of Bohmian trajectories used to describe the motion of massive particles.

  6. High energy electromagnetic particle transportation on the GPU

    Energy Technology Data Exchange (ETDEWEB)

    Canal, P. [Fermilab; Elvira, D. [Fermilab; Jun, S. Y. [Fermilab; Kowalkowski, J. [Fermilab; Paterno, M. [Fermilab; Apostolakis, J. [CERN

    2014-01-01

    We present massively parallel high energy electromagnetic particle transportation through a finely segmented detector on a Graphics Processing Unit (GPU). Simulating events of energetic particle decay in a general-purpose high energy physics (HEP) detector requires intensive computing resources, due to the complexity of the geometry as well as physics processes applied to particles copiously produced by primary collisions and secondary interactions. The recent advent of hardware architectures of many-core or accelerated processors provides the variety of concurrent programming models applicable not only for the high performance parallel computing, but also for the conventional computing intensive application such as the HEP detector simulation. The components of our prototype are a transportation process under a non-uniform magnetic field, geometry navigation with a set of solid shapes and materials, electromagnetic physics processes for electrons and photons, and an interface to a framework that dispatches bundles of tracks in a highly vectorized manner optimizing for spatial locality and throughput. Core algorithms and methods are excerpted from the Geant4 toolkit, and are modified and optimized for the GPU application. Program kernels written in C/C++ are designed to be compatible with CUDA and OpenCL and with the aim to be generic enough for easy porting to future programming models and hardware architectures. To improve throughput by overlapping data transfers with kernel execution, multiple CUDA streams are used. Issues with floating point accuracy, random numbers generation, data structure, kernel divergences and register spills are also considered. Performance evaluation for the relative speedup compared to the corresponding sequential execution on CPU is presented as well.

  7. Studies of exposure of rabbits to electromagnetic pulsed fields

    International Nuclear Information System (INIS)

    Cleary, S.F.; Nickless, F.; Liu, L.M.; Hoffman, R.

    1980-01-01

    Dutch rabbits were acutely exposed to electromagnetic pulsed (EMP) fields (pulse duration 0.4 mus, field strengths of 1--2 kV/cm and pulse repetition rates in the range of 10 to 38 Hz) for periods of up to two hours. The dependent variables investigated were pentobarbital-induced sleeping time and serum chemistry (including serum triglycerides, creatine phosphokinase (CPK) isoenzymes, and sodium and potassium). Core temperature measured immediately pre-exposure and postexposure revealed no exposure-related alterations. Over the range of field strengths and pulse durations investigated no consistent, statistically significant alterations were found in the end-points investigated

  8. Steady electric fields and currents elementary electromagnetic theory

    CERN Document Server

    Chirgwin, B H; Kilmister, C W

    2013-01-01

    Steady Electric Fields and Currents, Volume 1 is an introductory text to electromagnetism and potential theory. This book starts with the fields associated with stationary charges and unravels the stationary condition to allow consideration of the flow of steady currents in closed circuits. The opening chapter discusses the experimental results that require mathematical explanation and discussion, particularly those referring to phenomena that question the validity of the simple Newtonian concepts of space and time. The subsequent chapters consider steady-state fields, electrostatics, dielectr

  9. Photoproduction of gravitons and dilatons in an external electromagnetic field

    International Nuclear Information System (INIS)

    Le Khac Huong; Hoang Ngoc Long.

    1990-07-01

    An attempt is made to present experimental predictions of the Kaluza-Klein based models. We consider the creation of gravitons and dilatons by photons in an external electromagnetic field, namely in the electric field of a flat condenser and in the static magnetic field. The relation between the cross sections of these two processes is given. A numerical evaluation shows that in the present technical scenario the creation of high frequency gravitons and dilatons may be indirectly observable. (author). 10 refs, 2 figs

  10. Biological effects of electromagnetic fields | Yalçın | African Journal ...

    African Journals Online (AJOL)

    Recently, the possible effects of extra low frequency electromagnetic fields on the public health have become an interesting subject. Generally, electromagnetic fields occur around the high voltage lines. However, electromagnetic fields also occur with some electrical machines use for fun and TV used routinely at our home ...

  11. Retraction: Evaluation of Carcinogenic Effects of Electromagnetic Fields (Emf

    Directory of Open Access Journals (Sweden)

    Bakir Mehic

    2010-08-01

    Full Text Available This retracts the article "EVALUATION OF CARCINOGENIC EFFECTS OF ELECTROMAGNETIC FIELDS (EMF" on page 245. The Editor-in-chief of the Bosnian Journal ofBasic Medical Sciences has decided to retract the article from Bayazit V et al. [1] entitled as: “Evaluation of carcinogenic effects of electromagnetic fields (EMF” published in Bosn J Basic Med Sci. 2010 Aug;10(3:245-50.After the editorial office was alerted of possible plagiarism in the article, it conducted thorough investigation and concluded that the article apparently represents plagiarized material from two World Health Organization reports, one European Commission report and other sources. Since this is considered scientific plagiarism and scientific misconduct, Editor-in-chief has decided to withdraw the article. The authors have agreed with the editorial office decision.

  12. Uniform electromagnetic field as viscous medium for moving particles

    International Nuclear Information System (INIS)

    Amusia, M.Ya.; Baltenkov, A.S.; Felfli, Z.; Msezane, A.Z.; Voitkiv, A.B.

    2002-01-01

    The mechanism of transverse radiation viscosity acting on free charges, atomic, and small macroscopic particles in uniform electromagnetic fields is analyzed. It is shown that in the process of light scattering by these particles, besides the force accelerating them in the direction of propagation of the radiation, there is a force in the transverse direction slowing them down. The general expression for this force is obtained. It is considered how this force can influence: (i) the motion of ultrarelativistic electrons in transverse photon fluxes; (ii) the behavior of a beam of nonrelativistic electrons moving in a copropagating uniform electromagnetic field; (iii) the transverse motion of atoms under the action of resonant radiation and (iv) the motion of small macroscopic particles

  13. Radiofrequency electromagnetic fields in the Cookridge area of Leeds

    CERN Document Server

    Fuller, K; Judd, P M; Lowe, A J; Shaw, J

    2002-01-01

    On the 8 and 9 May 2002 representatives of the National Radiological Protection Board (NRPB) performed a radiofrequency electromagnetic field survey in the Cookridge area of Leeds in order to assess exposure to radio signals from transmitters mounted on a water tower/a lattice tower and a radio station tower. Guidelines on limiting exposure to radio signals have been published by NRPB and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). These guidelines are designed to prevent established adverse effects on human health. During this survey, the total exposures due to all radio signals from 30 MHz to 18000 MHz (18 GHz) were measured. This frequency range was chosen as it includes mobile phone base station transmissions, which are at around 900 and 1800 MHz and super high frequency (SHF) transmissions from most of the large microwave dish antennas mounted on the towers. In addition, other major sources of radiofrequency electromagnetic fields in the environment such as broadcast radio...

  14. Electromagnetic fields and health impact: measurements, monitoring and environmental indicators

    International Nuclear Information System (INIS)

    Lubritto, C.; Vetromile, C.; Petraglia, A.; Racioppoli, M.; D'Onofrio, A.

    2008-01-01

    Full text: During the last 10 years there has been a remarkable growth of the attention for problems related to the electromagnetic pollution, motivated by the alert connected to potential risk for the health of persons and due to the increasing diffusion of Bats for mobile telecommunication as EMF sources. Many projects are being realized about the environmental and health impact of electromagnetic field and an important social role is played by specific actions to minimize the risk perception of the population. This study aims to find an innovative approach to these problems through the use of a system of continuous time monitoring of the electromagnetic fields and the individuation of appropriate environmental indicators. The proposed system monitors the electromagnetic fields continuously over time, and is already operating in many southern Italian cities. It works in a very efficient way as a mean for: a) Info to the citizens, thanks to diffusion of daily collected data on Internet Web; b) Control for local administrations and Authorities, due to capability of the system itself to alert when measured values exceed the limits reported by the Italian laws; c) Planning, for the implementation of : 1) New procedures agreed among local environmental control agency, local administrations and mobile Companies for network planning and management of alarm situations; 2) New local guidelines documents concerning the installation and operation of telecommunications apparatus. Moreover, starting from the general principles of the Strategic Environmental Evaluation (VAS), the environmental impacts of EMS field is studied. Based on the model DPSIR (Drivers, Pressure, State, Impacts, Responses), 12 environmental indicators have been chosen providing an immediate and understandable tool to obtain very important information on electromagnetic pollution generated by radio-telecommunication systems. The selected environmental indicators have been applied to 11 cities of the

  15. Electromagnetic processes during phase commutation in field regulated reluctance machine

    Science.gov (United States)

    Shishkov, A. N.; Sychev, D. A.; Zemlyansky, A. A.; Krupnova, M. N.; Funk, T. A.; Ishmet'eva, V. D.

    2018-03-01

    The processes of currents switching in stator windings have been explained by the existence of the electromagnetic torque ripples in the electric drive with the field-regulated reluctance machine. The maximum value of ripples in the open loop control system for the six-phase machine can reach 20 percent from the developed electromagnetic torque. This method allows one to make calculation of ripple spike towards average torque developed by the electromotor for the different number of phases. Application of a trapezoidal form of current at six phases became the solution. In case of a less number of phases than six, a ripple spike considerably increases, which is inadmissible. On the other hand, increasing the number of phases tends to the increase of the semiconductor inverter external dimensions based on the inconspicuous decreasing of a ripple spike. The creation and usage of high-speed control loops of current (HCLC) have been recommended for a reduction of the electromagnetic torque’s ripple level, as well as the appliance of positive current feedback in switching phase currents. This decision allowed one to receive a mean value of the torque more than 10%, compared to system without change, to reduce greatly ripple spike of the electromagnetic torque. The possibility of the electric drive effective operation with FRRM in emergency operation has been shown.

  16. Immune Response to Electromagnetic Fields through Cybernetic Modeling

    International Nuclear Information System (INIS)

    Godina-Nava, J. J.; Segura, M. A. Rodriguez; Cadena, S. Reyes; Sierra, L. C. Gaitan

    2008-01-01

    We study the optimality of the humoral immune response through a mathematical model, which involves the effect of electromagnetic fields over the large lymphocytes proliferation. Are used the so called cybernetic variables in the context of the matching law of microeconomics or mathematical psychology, to measure the large lymphocytes population and to maximize the instantaneous antibody production rate in time during the immunologic response in order to most efficiently inactivate the antigen

  17. Immune Response to Electromagnetic Fields through Cybernetic Modeling

    Science.gov (United States)

    Godina-Nava, J. J.; Segura, M. A. Rodríguez; Cadena, S. Reyes; Sierra, L. C. Gaitán

    2008-08-01

    We study the optimality of the humoral immune response through a mathematical model, which involves the effect of electromagnetic fields over the large lymphocytes proliferation. Are used the so called cybernetic variables in the context of the matching law of microeconomics or mathematical psychology, to measure the large lymphocytes population and to maximize the instantaneous antibody production rate in time during the immunologic response in order to most efficiently inactivate the antigen.

  18. Electromagnetic field and the theory of conformal and biholomorphic invariants

    International Nuclear Information System (INIS)

    Lawrynowicz, J.

    1976-01-01

    This paper contains sections on: 1. Conformal invariance and variational principles in electrodynamics. 2. The principles of Dirichlet and Thomson as a physical motivation for the methods of conformal capacities and extremal lengths. 3. Extension to pseudoriemannian manifolds. 4. Extension to hermitian manifolds. 5. An extension of Schwarz's lemma for hermitian manifolds and its physical significance. 6. Variation of ''complex'' capacities within the admissible class of plurisubharmonic functions. The author concentrates on motivations and interpretations connected with the electromagnetic field. (author)

  19. Low-frequency electromagnetic field in a Wigner crystal

    OpenAIRE

    Stupka, Anton

    2016-01-01

    Long-wave low-frequency oscillations are described in a Wigner crystal by generalization of the reverse continuum model for the case of electronic lattice. The internal self-consistent long-wave electromagnetic field is used to describe the collective motions in the system. The eigenvectors and eigenvalues of the obtained system of equations are derived. The velocities of longitudinal and transversal sound waves are found.

  20. On the geometry of electromagnetic fields of second class

    International Nuclear Information System (INIS)

    Duggal, K.L.

    1983-01-01

    The notion of almost contingent manifolds was introduced by the author (1978) with a view to modify the standard Hermitian and Kaehlerian geometry applicable in relativity. The purpose of this paper is to use this extension as a free-way for developing the geometry of electromagnetic fields of second class under the framework of Hlavaty's (1961) classification. A mathematical model of the universe, called D-universe, having constant curvature has been created. (author)

  1. Electromagnetic Near Field Measurements of Two Critical Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Goettee, Jeffrey David

    2015-11-03

    The reactors employed, Godiva IV and WSMR Fast Burst Reactor, are described first. Then the point reactor kinetics model, electromagnetic potential, and the measurement of kinetics quantities are successively discussed. In summary, reactor power produces measurable electric energy. The electric signal mimics power curve for prompt burst operations - features in logarithmic derivatives match. The electric signature should be dependent on the power and not the derivative; therefore, steady-state modes should be measurable.

  2. Effect of energy emission from evanescent electromagnetic wave at scattering by a dielectric structure

    Energy Technology Data Exchange (ETDEWEB)

    Gulyaev, Yu.V. [Institute of Radioengineering and Electronics of the Russian Academy of Sciences, 125009 Moscow (Russian Federation); Barabanenkov, Yu.N. [Institute of Radioengineering and Electronics of the Russian Academy of Sciences, 125009 Moscow (Russian Federation)]. E-mail: yu.barab@mail.ip.sitek.net; Barabanenkov, M.Yu. [Institute of Microelectronics Technology and High Purity Materials of the Russian Academy of Sciences, 142432 Chernogolovka, Moscow Region (Russian Federation); Nikitov, S.A. [Institute of Radioengineering and Electronics of the Russian Academy of Sciences, 125009 Moscow (Russian Federation)

    2005-02-21

    We present an optical theorem for evanescent (near field) electromagnetic wave scattering by a dielectric structure. The derivation is based on the formalism of angular spectrum wave amplitudes. The optical theorem shows that an energy flux at scattering is emitted in the direction of incident evanescent wave decay.

  3. Electromagnetic separation of stable isotopes at the Institute of Atomic Energy, Academia Sinica

    International Nuclear Information System (INIS)

    Hua, M.; Li, G.; Su, S.; Mao, N.; Lu, H.

    1981-01-01

    For almost 20 years the Institute of Atomic Energy, Academia Sinica has been separating stable isotopes of the elements by electromagnetic separators and supplying these materials to research work in many fields of our country. In this article we shall attempt to outline the growth of the effort and describe the present situation. (orig.)

  4. Geiger-Nuttall Law for Nuclei in Strong Electromagnetic Fields

    Science.gov (United States)

    Delion, D. S.; Ghinescu, S. A.

    2017-11-01

    We investigate the influence of a strong laser electromagnetic field on the α -decay rate by using the Hennenberger frame of reference. We introduce an adimensional parameter D =S0/R0, where R0 is the geometrical nuclear radius and S0˜√{I }/ω2 is a length parameter depending on the laser intensity I and frequency ω . We show that the barrier penetrability has a strong increase for intensities corresponding to D >Dcrit=1 , due to the fact that the resulting Coulomb potential becomes strongly anisotropic even for spherical nuclei. As a consequence, the contribution of the monopole term increases the barrier penetrability by 2 orders of magnitude, while the total contribution has an effect of 6 orders of magnitude at D ˜3 Dcrit. In the case of deformed nuclei, the electromagnetic field increases the penetrability by an additional order of magnitude for a quadrupole deformation β2˜0.3 . The influence of the electromagnetic field can be expressed in terms of a shifted Geiger-Nuttal law by a term depending on S0 and deformation.

  5. Electromagnetic fields created by a macroparticle in an infinitely long and axisymmetric multilayer beam pipe

    CERN Document Server

    Mounet, N

    2009-01-01

    This paper aims at giving an as complete and detailed as possible derivation of the six electromagnetic field components created by an offset point charge travelling at any speed in an infinitely long circular multilayer beam pipe. Outcomes from this study are a novel and efficient matrix method for the field matching determination of all the constants involved in the field components, and the generalization to any azimuthal mode together with the final summation on all such modes in the impedance formulas. In particular the multimode direct space-charge impedances (both longitudinal and transverse) are given, as well as the wall impedance to any order of precision. New quadrupolar terms for the transverse wall impedance are found, which look negligible in the ultrarelativistic case but might be of significance for low-energy beams. In principle from this analysis the electromagnetic fields created by any particular source, with a finite transverse shape, can then be computed using convolutions.

  6. Beta Decay in the Field of an Electromagnetic Wave and Experiments on Measuring the Neutrino Mass

    International Nuclear Information System (INIS)

    Dorofeev, O.F.; Lobanov, A.E.

    2005-01-01

    Investigations of the effect of an electromagnetic wave field on the beta-decay process are used to analyze the tritium-decay experimental data on the neutrino mass. It is shown that the electromagnetic wave can distort the beta spectrum, shifting the end point to the higher energy region. This phenomenon is purely classical and it is associated with the electron acceleration in the radiation field. Since strong magnetic fields exist in setups for precise measurement of the neutrino mass, the indicated field can appear owing to the synchrotron radiation mechanism. The phenomenon under consideration can explain the experimentally observed anomalies in the spectrum of the decay electrons; in particular, the effect of the 'negative square of the neutrino mass'

  7. Electro-Magnetic Fields and Plasma in the Cosmos

    International Nuclear Information System (INIS)

    Scott, Donald E.

    2006-01-01

    It is becoming widely recognized that a majority of baryons in the cosmos are in the plasma state. But, fundamental disagreements about the properties and behavior of electro-magnetic fields in these plasmas exist between the science of modern astronomy and the experimentally verified laws of electrical engineering and physics. Some astronomers claim that magnetic fields can be open-ended - that they begin on or beneath the Sun's surface and extend outward to infinity. Astrophysicists have claimed that galactic magnetic fields begin and end on molecular clouds. Electrical engineers, most physicists, and the pioneers in electromagnetic field theory disagree - magnetic fields have no beginning or end. Since these two viewpoints are mutually exclusive, both cannot be correct; one must be completely false. Many astrophysicists claim that magnetic fields are 'frozen into' electric plasma. We also examine the basis for this claim. It has been shown to be incorrect in the laboratory. The hypothetical 'magnetic merging' mechanism is also reviewed in light of both theoretical and experimental investigations. The cause of large-scale filamentation in the cosmos is also simply revealed by experimental results obtained in plasma laboratories

  8. Thermodynamic fluctuations of electromagnetic field in slightly absorbing media

    Directory of Open Access Journals (Sweden)

    B.A.Veklenko

    2004-01-01

    Full Text Available A theory of thermodynamic fluctuations of electromagnetic field in slightly absorbing media is developed using the quantum electrodynamics - method of $Gamma$-operators - without phenomenology. The hypothesis offered by Yury L. Klimontovich is under consideration. The necessity of correct consideration of photon-photon correlation functions is shown. The results are compared with the ones obtained with the help of standard theory based upon fluctuation-dissipation theorem (FDT. The latter results are shown to have no field of application at least for the case of thermally excited media of the atoms described with two-level model.

  9. Electromagnetic field properties in the vicinity of a massive wormhole

    Energy Technology Data Exchange (ETDEWEB)

    Novikov, I. D.; Shatskiy, A. A., E-mail: shatskiy@asc.rssi.ru [Russian Academy of Sciences, Astro Space Centre, Lebedev Physical Institute (Russian Federation)

    2011-12-15

    It is proved that not only massless but also traversable massive wormholes can have electromagnetic 'hair.' An analysis is also presented of the passage from a traversable wormhole to the limit of a Reissner-Nordstroem black hole, with the corresponding disappearance of 'hair.' A general method is developed for solving stationary axisymmetric Maxwell's equations in the field of a massive, spherically symmetric wormhole. As a particular example of application of the method, a solution is found to the axisymmetric magnetostatic problem for a current loop in the field of the Bronnikov-Ellis-Morris-Thorne wormhole.

  10. Radiation reaction force and unification of electromagnetic and gravitational fields

    International Nuclear Information System (INIS)

    Lo, C.Y.; Goldstein, G.R.; Napier, A.

    1981-04-01

    A unified theory of electromagnetic and gravitational fields should modify classical electrodynamics such that the radiation reaction force is accounted for. The analysis leads to a five-dimensional unified theory of five variables. The theory is supported by showing that, for the case of a charged particle moving in a constant magnetic field, the radiation reaction force is indeed included. Moreover, this example shows explicitly that physical changes are associated with the fifth variable. Thus, the notion of a physical five-dimensional space should be seriously taken into consideration

  11. Additional external electromagnetic fields for laser microprocessing of metals.

    Science.gov (United States)

    Schütz, V; Bischoff, K; Brief, S; Koch, J; Suttmann, O; Overmeyer, L

    2016-11-14

    Ultra-short pulsed laser processing is a potent tool for microstructuring of a lot of materials. At certain laser parameters, particular periodical and/or quasi-periodical µm-size surface structures evolve apparently during processing. With extended plasmonics theory, it is possible to predict the structure formation, and a systematic technology can be derived to alter the surface for laser processing. In this work, we have demonstrated the modification of the laser processing with applying tailored dynamic surface electro-magnetic fields. Possible improvement in applications is seen in the fields of process efficiency of laser ablation and a superior control of the surface topography.

  12. Control of the electromagnetic drag using fluctuating light fields

    Science.gov (United States)

    Pastor, Víctor J. López; Marqués, Manuel I.

    2018-05-01

    An expression for the electromagnetic drag force experienced by an electric dipole in a light field consisting of a monochromatic plane wave with polarization and phase randomly fluctuating is obtained. The expression explicitly considers the transformations of the field and frequency due to the Doppler shift and the change of the polarizability response of the electric dipole. The conditions to be fulfilled by the polarizability of the dipole in order to obtain a positive, a null, and a negative drag coefficient are analytically determined and checked against numerical simulations for the dynamics of a silver nanoparticle. The theoretically predicted diffusive, superdiffusive, and exponentially accelerated dynamical regimes are numerically confirmed.

  13. Spectrum of classes of point emitters of electromagnetic wave fields.

    Science.gov (United States)

    Castañeda, Román

    2016-09-01

    The spectrum of classes of point emitters has been introduced as a numerical tool suitable for the design, analysis, and synthesis of non-paraxial optical fields in arbitrary states of spatial coherence. In this paper, the polarization state of planar electromagnetic wave fields is included in the spectrum of classes, thus increasing its modeling capabilities. In this context, optical processing is realized as a filtering on the spectrum of classes of point emitters, performed by the complex degree of spatial coherence and the two-point correlation of polarization, which could be implemented dynamically by using programmable optical devices.

  14. Magnetization reversal in ferromagnetic film through solitons by electromagnetic field

    International Nuclear Information System (INIS)

    Veerakumar, V.; Daniel, M.

    2001-07-01

    We study the reversal of magnetization in an isotopic ferromagnetic film free from charges by exposing it to a circularly polarized electromagnetic (EM) field. The magnetization excitations are obtained in the form of line and lump solitons of the completely integrable modified KP-II equation which is derived using a reductive perturbation method from the set of coupled Landau-Lifschitz and Maxwell equations. It is observed that when the polarization of the EM-field is reversed followed by a rotation, for every (π)/2-degrees, the magnetization is reversed. (author)

  15. Electron-electron interaction in strong electromagnetic fields The two-electron contribution to the ground-state energy in He-like uranium

    CERN Document Server

    Gumberidze, A; Barnás, D; Beckert, Karl; Beller, Peter; Beyer, H F; Bosch, F; Cai, X; Stöhlker, T; Hagmann, S; Kozhuharov, C; Liesen, D; Nolden, F; Ma, X; Mokler, P H; Orsic-Muthig, A; Steck, Markus; Sierpowski, D; Tashenov, S; Warczak, A; Zou, Y

    2004-01-01

    Radiative recombination transitions into the ground state of cooled bare and hydrogen-like uranium ions were measured at the storage ring ESR. By comparing the corresponding x-ray centroid energies, this technique allows for a direct measurement of the electron-electron contribution to the ionization potential in the heaviest He-like ions. For the two-electron contribution to the ionization potential of He-like uranium we obtain a value of 2248 ± 9 eV. This represents the most accurate determination of two-electron effects in the domain of high-Z He-like ions and the accuracy reaches already the size of the specific two-electron radiative QED corrections.

  16. Spin light of neutrino in matter and electromagnetic fields

    International Nuclear Information System (INIS)

    Lobanov, A.; Studenikin, A.

    2003-01-01

    A new type of electromagnetic radiation by a neutrino with non-zero magnetic (and/or electric) moment moving in background matter and electromagnetic field is considered. This radiation originates from the quantum spin flip transitions and we have named it as 'spin light of neutrino' (SLν). The neutrino initially unpolarized beam (equal mixture of ν L and ν R ) can be converted to the totally polarized beam composed of only ν R by the neutrino spin light in matter and electromagnetic fields. The quasi-classical theory of this radiation is developed on the basis of the generalized Bargmann-Michel-Telegdi equation. The considered radiation is important for environments with high effective densities, n, because the total radiation power is proportional to n 4 . The spin light of neutrino, in contrast to the Cherenkov or transition radiation of neutrino in matter, does not vanish in the case of the refractive index of matter is equal to unit. The specific features of this new radiation are: (i) the total power of the radiation is proportional to γ 4 , and (ii) the radiation is beamed within a small angle δθ∼γ -1 , where γ is the neutrino Lorentz factor. Applications of this new type of neutrino radiation to astrophysics, in particular to gamma-ray bursts, and the early universe should be important

  17. Nambu-Jona-Lasinio model in a parallel electromagnetic field

    Science.gov (United States)

    Wang, Lingxiao; Cao, Gaoqing; Huang, Xu-Guang; Zhuang, Pengfei

    2018-05-01

    We explore the features of the UA (1) and chiral symmetry breaking of the Nambu-Jona-Lasinio model without the Kobayashi-Maskawa-'t Hooft determinant term in the presence of a parallel electromagnetic field. We show that the electromagnetic chiral anomaly can induce both finite neutral pion condensate and isospin-singlet pseudo-scalar η condensate and thus modifies the chiral symmetry breaking pattern. In order to characterize the strength of the UA (1) symmetry breaking, we evaluate the susceptibility associated with the UA (1) charge. The result shows that the susceptibility contributed from the chiral anomaly is consistent with the behavior of the corresponding η condensate. The spectra of the mesonic excitations are also studied.

  18. Seminal magnetic fields from inflato-electromagnetic inflation

    Energy Technology Data Exchange (ETDEWEB)

    Membiela, Federico Agustin; Bellini, Mauricio [Universidad Nacional de Mar del Plata, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Mar del Plata (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Instituto de Investigaciones Fisicas de Mar del Plata (IFIMAR), Buenos Aires (Argentina)

    2012-10-15

    We extend some previous attempts to explain the origin and evolution of primordial magnetic fields during inflation induced from a 5D vacuum. We show that the usual quantum fluctuations of a generalized 5D electromagnetic field cannot provide us with the desired magnetic seeds. We show that special fields without propagation on the extra non-compact dimension are needed to arrive at appreciable magnetic strengths. We also identify a new magnetic tensor field B{sub ij} in this kind of extra dimensional theory. Our results are in very good agreement with observational requirements, in particular from TeV blazars and CMB radiation limits we see that primordial cosmological magnetic fields should be close to scale invariance. (orig.)

  19. Seminal magnetic fields from inflato-electromagnetic inflation

    Science.gov (United States)

    Membiela, Federico Agustín; Bellini, Mauricio

    2012-10-01

    We extend some previous attempts to explain the origin and evolution of primordial magnetic fields during inflation induced from a 5D vacuum. We show that the usual quantum fluctuations of a generalized 5D electromagnetic field cannot provide us with the desired magnetic seeds. We show that special fields without propagation on the extra non-compact dimension are needed to arrive at appreciable magnetic strengths. We also identify a new magnetic tensor field B ij in this kind of extra dimensional theory. Our results are in very good agreement with observational requirements, in particular from TeV blazars and CMB radiation limits we see that primordial cosmological magnetic fields should be close to scale invariance.

  20. Seminal magnetic fields from inflato-electromagnetic inflation

    International Nuclear Information System (INIS)

    Membiela, Federico Agustin; Bellini, Mauricio

    2012-01-01

    We extend some previous attempts to explain the origin and evolution of primordial magnetic fields during inflation induced from a 5D vacuum. We show that the usual quantum fluctuations of a generalized 5D electromagnetic field cannot provide us with the desired magnetic seeds. We show that special fields without propagation on the extra non-compact dimension are needed to arrive at appreciable magnetic strengths. We also identify a new magnetic tensor field B ij in this kind of extra dimensional theory. Our results are in very good agreement with observational requirements, in particular from TeV blazars and CMB radiation limits we see that primordial cosmological magnetic fields should be close to scale invariance. (orig.)

  1. Atom ionization in a nonclassical intense electromagnetic field

    International Nuclear Information System (INIS)

    Popov, A.M.; Tikhonova, O.V.

    2002-01-01

    The atoms ionization process in the intense nonclassical electromagnetic field is considered. It is shown that depending on the field quantum state the probability of ionization may essentially change even by one and the same average quantum number in the radiation mode, whereby the difference in the ionization rates is especially significant in the case, when the ionization process is of a multiphoton character. It is demonstrates in particular, that the nonclassical field may be considerably more intensive from the viewpoint of the atoms ionization, than the classical field with the same intensity. The peculiarities of the decay, related to the atomic system state in the strong nonclassical field beyond the perturbation theory frames are studied [ru

  2. Sound absorption in a field of a strong electromagnetic wave in a quantizied magnetic field

    International Nuclear Information System (INIS)

    Chajkovskij, I.A.

    1974-01-01

    A coefficient of sound absorption GAMMA in a semiconductor and semi-metal in the quantized magnetic field is calculated for a system exposed to a field of strong electromagnetic radiation. The cases E parallel H and E orthogonal H are considered. Along with the already known strong oscillations of sound absorption in magnetic fields, the absorption spectrum GAMMAsub(par) and GAMMAsub(orth) shows new oscillations representing a manifestation of the quasi-energetic electron spectrum in the field of a strong electromagnetic wave. The oscillation height at E parallel H is modulated by the electromagnetic field. It is shown that the ratio GAMMAsub(par)/GAMMAsub(orth) allows the determination of the effective mass of the carriers

  3. The universal C*-algebra of the electromagnetic field II. Topological charges and spacelike linear fields

    Science.gov (United States)

    Buchholz, Detlev; Ciolli, Fabio; Ruzzi, Giuseppe; Vasselli, Ezio

    2017-02-01

    Conditions for the appearance of topological charges are studied in the framework of the universal C*-algebra of the electromagnetic field, which is represented in any theory describing electromagnetism. It is shown that non-trivial topological charges, described by pairs of fields localised in certain topologically non-trivial spacelike separated regions, can appear in regular representations of the algebra only if the fields depend non-linearly on the mollifying test functions. On the other hand, examples of regular vacuum representations with non-trivial topological charges are constructed, where the underlying field still satisfies a weakened form of "spacelike linearity". Such representations also appear in the presence of electric currents. The status of topological charges in theories with several types of electromagnetic fields, which appear in the short distance (scaling) limit of asymptotically free non-abelian gauge theories, is also briefly discussed.

  4. Effects of electromagnetic fields on fecundity in the chicken.

    Science.gov (United States)

    Krueger, W F; Giarola, A J; Bradley, J W; Shrekenhamer, A

    1975-02-28

    Egg production was reduced when young laying hens were kept in contact with metal cages while being continuously exposed to the following cw fields: a vhf field at a frequency of 260 MHz, with an incident power that decreased from 100 to 4mW during the experiment; a uhf field at a frequency of 915 MHz, with an incident power of 800 mW during the first 2.5 weeks, zero during the following week, and 200 mW for the remainder of the experiment; a uhf field at 2.435 GHz, with an incident power of 800 mW; an elf electric field at a frequency of 60 Hz, with a calculated value of field strength of 1600 V/m; an elf magnetic field at 60 Hz, with a value of magnetic flux density of 1.4G. With the exception of the hens exposed to the uhf field at 915 MHz, all other treated groups laid significantly less eggs than the controls (p smaller than or equal to 0.01). This reduction (similar 15% less than the controls) began with the first 4-week production period. The egg production curves for the hens exposed to the vhf field at 260 MHz and to the uhf field at 2.435 GHz were approximately the same beginning with the sixth week of production, and they maintained comparable production levels for the remainder of the experiment. An 8% total drop in production also was experienced in the group of birds exposed to the 915-MHz field, which pulsed because of equipment failure. Egg production rate curves for the birds in the elf electric and magnetic fields were substantially different from those exhibited by birds in the other electromagnetic fields. The birds in the E-field regained a production level comparable to the controls after 11 weeks production, whereas those in the B-field dropped to 31% production, which was approximately 40% poorer than the controls by the twelfth week of production. Fertility of cocks and hens was not affected by continuous low-power vhf and uhf near-zone electromagnetic exposure or elf electric or magnetic field treatment. Fertility was exceptionally good

  5. Polarization phenomena in electromagnetic interactions at intermediate energies

    International Nuclear Information System (INIS)

    Burkert, V.

    1990-01-01

    Recent results of polarization measurements in electromagnetic interactions at intermediate energies are discussed. Prospects of polarization experiments at the new CW electron accelerators, as well as on upgraded older machines are outlined. It is concluded that polarization experiments will play a very important role in the study of the structure of the nucleon and of light nuclei. 72 refs

  6. The electromagnetic virtual cloud of the ground-state hydrogen atom - a quantum field theory approach

    International Nuclear Information System (INIS)

    Radozycki, T.

    1990-01-01

    The properties of the virtual cloud around the hydrogen atom in the ground state are studied with the use of quantum field theory methods. The relativistic expression for the electromagnetic energy density around the atom, with the electron spin taken into account, is obtained. The distribution of the angular momentum contained in the cloud and the self-interaction kernel for the electrons bound in atom are also investigated. (author)

  7. Near-field electromagnetic holography for high-resolution analysis of network interactions in neuronal tissue.

    Science.gov (United States)

    Kjeldsen, Henrik D; Kaiser, Marcus; Whittington, Miles A

    2015-09-30

    Brain function is dependent upon the concerted, dynamical interactions between a great many neurons distributed over many cortical subregions. Current methods of quantifying such interactions are limited by consideration only of single direct or indirect measures of a subsample of all neuronal population activity. Here we present a new derivation of the electromagnetic analogy to near-field acoustic holography allowing high-resolution, vectored estimates of interactions between sources of electromagnetic activity that significantly improves this situation. In vitro voltage potential recordings were used to estimate pseudo-electromagnetic energy flow vector fields, current and energy source densities and energy dissipation in reconstruction planes at depth into the neural tissue parallel to the recording plane of the microelectrode array. The properties of the reconstructed near-field estimate allowed both the utilization of super-resolution techniques to increase the imaging resolution beyond that of the microelectrode array, and facilitated a novel approach to estimating causal relationships between activity in neocortical subregions. The holographic nature of the reconstruction method allowed significantly better estimation of the fine spatiotemporal detail of neuronal population activity, compared with interpolation alone, beyond the spatial resolution of the electrode arrays used. Pseudo-energy flow vector mapping was possible with high temporal precision, allowing a near-realtime estimate of causal interaction dynamics. Basic near-field electromagnetic holography provides a powerful means to increase spatial resolution from electrode array data with careful choice of spatial filters and distance to reconstruction plane. More detailed approaches may provide the ability to volumetrically reconstruct activity patterns on neuronal tissue, but the ability to extract vectored data with the method presented already permits the study of dynamic causal interactions

  8. Interference effects at photoionization of Rydberg atoms by a strong electromagnetic field

    International Nuclear Information System (INIS)

    Movsesyan, A.M.; Fedorov, M.V.

    1989-01-01

    The photoionization of Rydberg atoms in a strong electromagnetic field is considered. Degeneration of the levels with respect to the orbital moment, their Stark splitting and the possibility of resonant interaction with levels of lower energy are taken into account. The complex quasi-energies of the system, photoelectron spectrum in the limit of an infinite duration of interaction and the time dependence of the total ionization probability are found. It is shown that a narrowing of the quasi-energy levels occurs in a strong field. Against a background of the quasi- continuum the quasi-energy spectrum consists of more or less narrow levels. In this case the photoelectron spectrum acquires a multi-peak form. With increasing field strength the height of the peaks increases, whereas their width decreases. The ionization rate decreases with increasing field strength. The presence of a quasi-continuum is the cause of the partially non-exponential nature of the atomic disintegration

  9. Multiphoton processes in the field of two-frequency circularly polarized plane electromagnetic waves

    International Nuclear Information System (INIS)

    Yu, An

    1997-01-01

    The authors solve Dirac's equation for an electron in the field of a two-frequency plane electromagnetic wave, deriving general formulae for the probabilities of radiation of a photon by the electron, and for the probabilities for pair production by a photon when the two-frequency wave is circularly polarized. In contrast to the case of a monochromatic-plane electromagnetic wave, when an electron is in the field of a two-frequency circularly polarized wave, besides the absorption of multiphotons and emission of simple harmonics of the individual waves, stimulated multiphoton emission processes and various composite harmonic-photon emission processes are occurred: when a high-energy photon is in a such a field, multiphoton processes also follow the pair production processes

  10. Electromagnetic waves destabilized by runaway electrons in near-critical electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Komar, A.; Pokol, G. I. [Department of Nuclear Techniques, Budapest University of Technology and Economics, Association EURATOM, H-1111 Budapest (Hungary); Fueloep, T. [Department of Applied Physics, Nuclear Engineering, Chalmers University of Technology and Euratom-VR Association, Goeteborg (Sweden)

    2013-01-15

    Runaway electron distributions are strongly anisotropic in velocity space. This anisotropy is a source of free energy that may destabilize electromagnetic waves through a resonant interaction between the waves and the energetic electrons. In this work, we investigate the high-frequency electromagnetic waves that are destabilized by runaway electron beams when the electric field is close to the critical field for runaway acceleration. Using a runaway electron distribution appropriate for the near-critical case, we calculate the linear instability growth rate of these waves and conclude that the obliquely propagating whistler waves are most unstable. We show that the frequencies, wave numbers, and propagation angles of the most unstable waves depend strongly on the magnetic field. Taking into account collisional and convective damping of the waves, we determine the number density of runaways that is required to destabilize the waves and show its parametric dependences.

  11. Electromagnetic field of a circular beam of relativistic particles

    International Nuclear Information System (INIS)

    Vybiral, B.

    1978-01-01

    The generalized Coulomb law and the generalized Biot-Savart-Laplace law are derived for an element of a beam of charged relativistic particles moving generally irregularly. These laws are utilized for the description of an electromagnetic field of a circular beam of relativistic regularly moving particles. It is shown that in the points on the axis of the beam the intensity of the electric field is given by an expression precisely corresponding to the classical Coulomb law for charges at rest and the induction of the magnetic field corresponds to the classical Biot-Savart-Laplace law for conductive currents. From the numerical solution it follows that in the points outside the axis the induction of the magnetic field rises with the velocity of the particles. For a velocity nearing that of light in vacuum it assumes a definite value (with the exception of the points lying on the beam). (author)

  12. ELECTRON HOLOGRAPHY OF ELECTROMAGNETIC FIELDS - RECENT THEORETICAL ADVANCES.

    Energy Technology Data Exchange (ETDEWEB)

    BELEGGIA,M.; POZZI, G.; TONOMURA, A.

    2007-01-01

    It has been shown in this work that the Fourier space approach can be fruitfully applied to the calculation of the fields and the associated electron optical phase shift of several magnetic and electrostatic structures, like superconducting vortices in conventional and high-T{sub c} superconductors, reverse biased p-n junctions, magnetic domains and nanoparticles. In all these cases, this novel approach has led to unexpected but extremely interesting results, very often expressed in analytical form, which allow the quantitative and reliable interpretation of the experimental data collected by means of electron holography or of more conventional Lorentz microscopy techniques. Moreover, it is worth recalling that whenever long-range electromagnetic fields are involved, a physical model of the object under investigation is necessary in order to take into account correctly the perturbation of the reference wave induced by the tail of the field protruding into the vacuum. For these reasons, we believe that the Fourier space approach for phase computations we have introduced and discussed in this chapter will represent an invaluable tool for the investigation of electromagnetic fields at the meso- and nano-scale.

  13. An electromagnetic field measurement protocol for monitoring power lines

    International Nuclear Information System (INIS)

    Lubritto, C.; Iavazzo, A.; D'Onofrio, A.; Palmieri, A.; Sabbarese, C.; Terrasi, F.

    2002-01-01

    In the actions aiming to prevent risks related to the exposure to Low Frequencies Non Ionising electromagnetic Radiations (ELF-NIR), always arises the need to perform measurements in order to assess the field level existing in the considered sites. As a matter of fact very often it turns out difficult to predict, on the base of calculations, with sufficient approximation the field levels, due to extended variability of environmental conditions (e.g. coexistence of several sources, ground and building conformation, etc..). The measurement procedures must follow a methodology that could allow to minimise the interferences with the measurement set-up and the systematic and accidental errors. Risks for the operator and damages to the instrument should also be taken into account. One of the goal set for this research program was then the definition of the measurement protocol for electromagnetic field generated by low frequency non ionising radiation sources. In particular sources like power lines will be considered in order to validate the protocol by means of in-field measurements

  14. Wigner functions for nonparaxial, arbitrarily polarized electromagnetic wave fields in free space.

    Science.gov (United States)

    Alonso, Miguel A

    2004-11-01

    New representations are defined for describing electromagnetic wave fields in free space exactly in terms of rays for any wavelength, level of coherence or polarization, and numerical aperture, as long as there are no evanescent components. These representations correspond to tensors assigned to each ray such that the electric and magnetic energy densities, the Poynting vector, and the polarization properties of the field correspond to simple integrals involving these tensors for the rays that go through the specified point. For partially coherent fields, the ray-based approach provided by the new representations can reduce dramatically the computation times for the physical properties mentioned earlier.

  15. Non-relativistic correspondence of Dirac equation with external electromagnetic field and space-time torsion

    International Nuclear Information System (INIS)

    Goncalves, Bruno; Dias Junior, Mario Marcio

    2013-01-01

    Full text: The discussion of experimental manifestations of torsion at low energies is mainly related to the torsion-spin interaction. In this respect the behavior of Dirac field and the spinning particle in an external torsion field deserves and received very special attention. In this work, we consider the combined action of torsion and magnetic field on the massive spinor field. In this case, the Dirac equation is not straightforward solved. We suppose that the spinor has two components. The equations have mixed terms between the two components. The electromagnetic field is introduced in the action by the usual gauge transformation. The torsion field is described by the field S μ . The main purpose of the work is to get an explicit form to the equation of motion that shows the possible interactions between the external fields and the spinor in a Hamiltonian that is independent to each component. We consider that S 0 is constant and is the unique non-vanishing term of S μ . This simplification is taken just to simplify the algebra, as our main point is not to describe the torsion field itself. In order to get physical analysis of the problem, we consider the non-relativistic approximation. The final result is a Hamiltonian that describes a half spin field in the presence of electromagnetic and torsion external fields. (author)

  16. Mapping the absolute electromagnetic field strength of individual field components inside a photonic crystal

    NARCIS (Netherlands)

    Denis, T.; Reijnders, B.; Lee, J.H.H.; Vos, Willem L.; Boller, Klaus J.; van der Slot, Petrus J.M.

    2013-01-01

    We present a method to map the absolute electromagnetic field strength inside photonic crystals. We demonstrate our method by applying it to map the electric field component Ez of a two-dimensional photonic crystal slab at microwave frequencies. The slab is placed between two mirrors to create a

  17. Conflict field energy

    International Nuclear Information System (INIS)

    Krebsbach-Gnath, C.

    1981-01-01

    Violent social controversies characterize the treatment of the energy problem. Solutions of this conflict decisively depend on the knowledge and evaluation of the causes and the possible development. How is it possible to explain the opinions, views, and the attitude of the population to different kinds of energy. Which factors are decisive for the explosive effect and the stability of the conflict in the field of nulcear energy. What will happen when there arises a possible lack of energy. Which socio-political effects will such a lack have. Are there new proposals for solving problems in the nulcear-energy debate. The contributions of this book are results of scientific and empiric works. They provide perceptive approaches and analyses to the problems and by discussing them are useful in giving an orientation for political action. (orig.) [de

  18. The Characteristics of Electromagnetic Fields Induced by Different Type Sources

    Science.gov (United States)

    Di, Q.; Fu, C.; Wang, R.; Xu, C.; An, Z.

    2011-12-01

    Controlled source audio-frequence magnetotelluric (CSAMT) method has played an important role in the shallow exploration (less than 1.5km) in the field of resources, environment and engineering geology. In order to prospect the deeper target, one has to increase the strength of the source and offset. However, the exploration is nearly impossible for the heavy larger power transmitting source used in the deeper prospecting and mountain area. So an EM method using a fixed large power source, such as long bipole current source, two perpendicular "L" shape long bipole current source and large radius circle current source, is beginning to take shape. In order to increase the strength of the source, the length of the transmitting bipole in one direction or in perpendicular directions has to be much larger, such as L=100km, or the radius of the circle current source is much larger. The electric field strength are IL2and IL2/4π separately for long bipole source and circle current source with the same wire length. Just considering the effectiveness of source, the strength of the circle current source is larger than that of long bipole source if is large enough. However, the strength of the electromagnetic signal doesn't totally depend on the transmitting source, the effect of ionosphere on the electromagnetic (EM) field should be considered when observation is carried at a very far (about several thousands kilometers) location away from the source for the long bipole source or the large radius circle current source. We firstly calculate the electromagnetic fields with the traditional controlled source (CSEM) configuration using the integral equation (IE) code developed by our research group for a three layers earth-ionosphere model which consists of ionosphere, atmosphere and earth media. The modeling results agree well with the half space analytical results because the effect of ionosphere for this small scale source can be ignorable, which means the integral equation

  19. The Mathematics of Charged Particles interacting with Electromagnetic Fields

    DEFF Research Database (Denmark)

    Petersen, Kim

    In this thesis, we study the mathematics used to describe systems of charged quantum mechanical particles coupled with their classical self-generated electromagnetic field. We prove the existence of a unique local in time solution to the many-body Maxwell-Schrödinger initial value problem expressed...... in Coulomb gauge and we show that the one-body Maxwell-Schrödinger system as well as the related one-body Maxwell-Pauli system both admit travelling wave solutions....

  20. Delayed consequences of biological action of electromagnetic fields

    International Nuclear Information System (INIS)

    Grigor'ev, Yu.G.

    2000-01-01

    Based on available data the real possibility of development of delayed effects in people of long-term electromagnetic fields (EMF) exposure is considered. It is shown that is a relation between long-term EMF-exposure and development of the breast cancer, brain tumors, leukemia and neurodegenerative diseases (Alzheimer's and Parkinson's diseases, amyotrophic lateral sclerosis). Analysis of up-to-date publications permit to conclude that this problem is urgent and further researches of the conditions promoting the development of delayed effects are required [ru

  1. Clinical update of pulsed electromagnetic fields on osteoporosis

    Institute of Scientific and Technical Information of China (English)

    HUANG Li-qun; HE Hong-chen; HE Cheng-qi; CHEN Jian; YANG Lin

    2008-01-01

    Objective To understand the effects of low-frequency pulsed electromagnetic fields (PEMFs) on chronic bony pain,bone mineral density (BMD), bone strength and biochemical markers of bone metabolism in the patients of osteoporosis.Data sources Using the key words "pulsed electromagnetic fields" and "osteoporosis", we searched the PubMed for related studies published in English from January 1996 to December 2007. We also searched the China National Knowledge Infrastructure (CNKI) for studies published in Chinese from January 1996 to December 2007.Study selection Inclusion criteria: (1) all articles which referred to the effects of low-frequency pulsed magnetic fields on osteoporosis either in primary osteoporosis or secondary osteoporosis; (2) either observational studies or randomized controlled studies. Exclusion criteria: (1) articles on experimental studies about osteoporosis; (2) repetitive studies; (3)case reports; (4) meta analysis.Results Totally 111 related articles were collected, 101 of them were published in Chinese, 10 were in English.Thirty-four were included and the remaining 84 were excluded.Conclusions Low-frequency PEMFs relieves the pain of primary osteoporosis quickly and efficiently, enhances bone formation and increases BMD of secondary osteoporosis. But the effects of PEMFs on bone mineral density of primary osteoporosis and bone resorption were controversial.

  2. International conference on electromagnetic fields hazard protection of the human being

    International Nuclear Information System (INIS)

    Grigor'ev, Yu.G.

    1999-01-01

    The Second International conference concerning the problems of electromagnetic protection of the human being, fundamental and applied studies, normalization of the EMP: philosophy, criteria and harmonization which took place in Moscow in September 1999 is reported. The topics of reports covered both the mechanism of biological action of electromagnetic fields and aspects of impact of electromagnetic fields from various household appliances on the health of practically all modern people (television, radio, energetic, communication). The plenary section on evaluation of hazards of the mobile communication electromagnetic fields and the round table meeting dealing with evaluation of hazards of electromagnetic fields of the cellular communication base stations were conducted in the course of the conference. The plenary meetings were devoted to harmonization of the electromagnetic protection standards of Russia and western countries. The above conference constitutes one of the stages of the WHO international program concerning electromagnetic fields and the human being [ru

  3. The question of health effects from exposure to electromagnetic fields

    International Nuclear Information System (INIS)

    Grandolfo, M.

    1996-01-01

    The question of health effects related to exposures from non-ionizing and non-optical electromagnetic fields is currently concentrated in two frequency ranges: extremely low frequency (ELF) electric and magnetic fields, mainly at the overhead high-voltage power line frequencies of 50/60 Hz, and radiofrequency (RF) radiation, encompassing the frequency range from a few kilohertz to 300 GHz. The part between 300 MHz and 300 GHz is also usually named microwaves (MW); from this point of view, microwaves are part of the whole RF spectrum. The following brief overview is aimed at evaluating the state of knowledge regarding the question of health effects associated to exposures to ELF and RF/MW fields

  4. Structures, systems and methods for harvesting energy from electromagnetic radiation

    Science.gov (United States)

    Novack, Steven D [Idaho Falls, ID; Kotter, Dale K [Shelley, ID; Pinhero, Patrick J [Columbia, MO

    2011-12-06

    Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.

  5. Electromagnetic energy applications in lunar resource mining and construction

    International Nuclear Information System (INIS)

    Lindroth, D.P.; Podnieks, E.R.

    1988-01-01

    Past work during the Apollo Program and current efforts to determine extraterrestrial mining technology requirements have led to the exploration of various methods applicable to lunar or planetary resource mining and processing. The use of electromagnetic energy sources is explored and demonstrated using laboratory methods to establish a proof of concept for application to lunar mining, construction, and resource extraction. Experimental results of using laser, microwave, and solar energy to fragment or melt terrestrial basal under atmospheric and vacuum conditions are presented. Successful thermal stress fragmentation of dense igneous rock was demonstrated by all three electromagnetic energy sources. The results show that a vacuum environment has no adverse effects on fragmentation by induced thermal stresses. The vacuum environment has a positive effect for rock disintegration by melting, cutting, or penetration applications due to release of volatiles that assist in melt ejection. Consolidation and melting of basaltic fines are also demonstrated by these methods

  6. Electromagnetic energy transport in nanoparticle chains via dark plasmon modes.

    Science.gov (United States)

    Solis, David; Willingham, Britain; Nauert, Scott L; Slaughter, Liane S; Olson, Jana; Swanglap, Pattanawit; Paul, Aniruddha; Chang, Wei-Shun; Link, Stephan

    2012-03-14

    Using light to exchange information offers large bandwidths and high speeds, but the miniaturization of optical components is limited by diffraction. Converting light into electron waves in metals allows one to overcome this problem. However, metals are lossy at optical frequencies and large-area fabrication of nanometer-sized structures by conventional top-down methods can be cost-prohibitive. We show electromagnetic energy transport with gold nanoparticles that were assembled into close-packed linear chains. The small interparticle distances enabled strong electromagnetic coupling causing the formation of low-loss subradiant plasmons, which facilitated energy propagation over many micrometers. Electrodynamic calculations confirmed the dark nature of the propagating mode and showed that disorder in the nanoparticle arrangement enhances energy transport, demonstrating the viability of using bottom-up nanoparticle assemblies for ultracompact opto-electronic devices. © 2012 American Chemical Society

  7. Optimizing the energy measurement of the ATLAS electromagnetic calorimeter

    International Nuclear Information System (INIS)

    Lampl, W.

    2005-12-01

    This PhD-thesis addresses the calibration of the ATLAS electromagnetic calorimeter. ATLAS is a high-energy physics experiment at the Large Hadron Collider (LHC) which is currently under construction at CERN in Geneva. LHC and ATLAS are foreseen to start up in 2007. In summer 2004, an extensive beam-test was carried out. This means that individual detector modules are exposed to a particle beam of known energy in order to verify the detector performance. At this occasion, all ATLAS subdetectors where operated together for the first time. The thesis contains a comprehensive description of the ATLAS electromagnetic calorimeter, the reconstruction software and the test-beam experiment that was carried out at CERN in 2004. Furthermore, the physics of the electromagnetic shower is discussed in detail. Data from the test beam as well as a detailed Monte-Carlo simulation are used to develop a novel energy-reconstruction method for the ATLAS EM calorimeter that achieves an excellent energy resolution (sampling term ∼ 11 %) as well as a very good linearity (< 0.4 %). Data taken during the beam test is also used to verify the accuracy of the simulation and to test the new energy-reconstruction method. (author)

  8. Correction magnetic field in electromagnet of proton accelerator using CST software; Correcao do campo magnetico em um eletroima de um acelerador de protons usando o software CST

    Energy Technology Data Exchange (ETDEWEB)

    Rabelo, L.A.; Campos, T.P.R., E-mail: luisarabelo88@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Dept. de Engenharia Nuclear

    2016-07-01

    The aim of this paper is to present the study and simulation of uniform magnetic field electromagnets new circular accelerator model for protons with energy range between 15 MeV and 64 MeV. In addition, investigating materials and the changes induced by the presence of 'gaps' synchronism correction. The electromagnet simulations, predefined, were made in electromagnetic field simulation software CST EM Studio® 3D 2015. The results showed an even distribution of the magnetic field in the compact electromagnet with the same homogenization structures. The results showed regular distribution of the magnetic field in the compact electromagnet with homogenization structures. In conclusion, the electromagnetic model proposed shown to be feasible for a circular accelerator and comply the synchronization requirements. (author)

  9. Strings: A possible alternative explanation for the Unification of Gravitation Field and Electromagnetic Field

    Science.gov (United States)

    Rivera, Susana

    Throughout the last century, since the last decades of the XIX century, until present day, there had been many attempts to achieve the unification of the Forces of Nature. First unification was done by James Clerk Maxwell, with his Electromagnetic Theory. Then Max Plank developed his Quantum Theory. In 1905, Albert Einstein gave birth to the Special Relativity Theory, and in 1916 he came out with his General Relativity Theory. He noticed that there was an evident parallelism between the Gravitational Force, and the Electromagnetic Force. So, he tried to unify these forces of Nature. But Quantum Theory interposed on his way. On the 1940’s it had been developed the Quantum Electrodynamics (QED), and with it, the unified field theory had an arise interest. On the 60’s and 70’s there was developed the Quantum Chromodynamics (QCD). Along with these theories came the discovery of the strong interaction force and weak interaction force. And though there had been many attempts to unify all these forces of the nature, it could only be achieved the Unification of strong interaction, weak interaction and Electromagnetic Force. On the late 80”s and throughout the last two decades, theories such as “super-string theory”, “or the “M-theory”, among others, groups of Scientists, had been doing grand efforts and finally they came out with the unification of the forces of nature, being the only limitation the use of more than 11 dimensions. Using an ingenious mathematical tool known as the super symmetries, based on the Kaluza - Klein work, they achieve this goal. The strings of these theories are in the rank of 10-33 m. Which make them undetectable. There are many other string theories. The GEUFT theory is based on the existence of concentrated energy lines, which vibrates, expands and contracts, submitting and absorbing energy, matter and antimatter, and which yields a determined geometry, that gives as a result the formation of stars, galaxies, nebulae, clusters

  10. Energy from field crops

    Energy Technology Data Exchange (ETDEWEB)

    Zubr, J.

    1990-04-15

    At the Research Station of Royal Veterinary and Agricultural University, Copenhagen, Denmark, investigation concerning cultivation and exploitation of field crops for production of fuels was carried out during the period 1986-1989. High yielding crops, such as sugar beet - BETA VULGARIS, jerusalem artichoke - HELIANTHUS TUBEROSUS, rhubarb - RHEUM RHAPONTICUM, and comfrey - SYMPHYTUM ASPERUM, were grown experimentally in the field. Different cultivation methods for the crops were used and evaluated. Simultaneously with the field experiment, laboratory investigation was carried out to determine the energy potential of different products and by-products from the crops processes, such as alcoholic and methanogenic fermantation. Production expenses for the crops were determined, and cost of the fuels was estimated. The experimental results show that beet is a superior crop for the climatic conditions of Northern Europe. In the season 1986, yields exceeded 20 t TS/ha in the form of roots and tops, where achieved. A combined exploitation of beet roots and tops via alcoholic and methanogenic fermantation gave a gross energy corresponding to 80 hl OE/ha/yr. Using methanogenic fermentation exclusively, from ensiled beet roots and tops, gross energy yield corresponding to 85 hl IE/ha/yr, was achieved. The cost of energy in the form of alcohol from beet roots was estimated to be 5.17 DKK/1 OE (0.64 ECU/l OE). The cost of energy in the form of methane from ensiled beet tops, was estimated to be 2.68 DKK/l OE (0.33 ECU/l OE). At the present time, methane produced on the basis of ensiled beet roots and tops appears to be competitive with fossil fuels. Irrespective of the cost, however, the possibility of producing clean energy from field crops remains of interest for the future. (author) 27 refs.

  11. Sensor Interaction as a Source of the Electromagnetic Field Measurement Error

    Directory of Open Access Journals (Sweden)

    Hartansky R.

    2014-12-01

    Full Text Available The article deals with analytical calculation and numerical simulation of interactive influence of electromagnetic sensors. Sensors are components of field probe, whereby their interactive influence causes the measuring error. Electromagnetic field probe contains three mutually perpendicular spaced sensors in order to measure the vector of electrical field. Error of sensors is enumerated with dependence on interactive position of sensors. Based on that, proposed were recommendations for electromagnetic field probe construction to minimize the sensor interaction and measuring error.

  12. Dynamical characteristics of an electromagnetic field under conditions of total reflection

    Science.gov (United States)

    Bekshaev, Aleksandr Ya

    2018-04-01

    The dynamical characteristics of electromagnetic fields include energy, momentum, angular momentum (spin) and helicity. We analyze their spatial distributions near the planar interface between two transparent and non-dispersive media, when the incident monochromatic plane wave with arbitrary polarization is totally reflected, and an evanescent wave is formed in the medium with lower optical density. Based on the recent arguments in favor of the Minkowski definition of the electromagnetic momentum in a material medium (Philbin 2011 Phys. Rev. A 83 013823; Philbin and Allanson 2012 86 055802; Bliokh et al 2017 Phys. Rev. Lett. 119 073901), we derive the explicit expressions for the dynamical characteristics in both media, with special attention to their behavior at the interface. In particular, the ‘extraordinary’ spin and momentum components orthogonal to the plane of incidence are described, and a canonical (spin-orbital) momentum decomposition is performed that contains no singular terms. The field energy, helicity, the spin momentum and orbital momentum components are everywhere regular but experience discontinuities at the interface; the spin components parallel to the interface appear to be continuous, which testifies to the consistency of the adopted Minkowski picture. The results supply a meaningful example of the electromagnetic momentum decomposition, with separation of spatial and polarization degrees of freedom, in inhomogeneous media, and can be used in engineering the structured fields designed for optical sorting, dispatching and micromanipulation.

  13. Non-linear diffusion of charged particles due to stochastic electromagnetic fields

    International Nuclear Information System (INIS)

    Martins, A.M.; Balescu, R.; Mendonca, J.T.

    1989-01-01

    It is well known that the energy confinement times observed in tokamak cannot be explained by the classical or neo-classical transport theory. The alternative explanations are based on the existence of various kinds of micro-instabilities, or on the stochastic destruction of the magnetic surfaces, due to the interaction of magnetic islands of different helicities. In the absence of a well established theory of anomalous transport it is perhaps important to study in some detail the diffusion coefficient of single charged particles in the presence of electromagnetic fluctuation, because it can provide the physical grounds for more complete and self-consistent calculations. In the present work we derive a general expression for the transverse diffusion coefficient of electrons and ions in a constant magnetic field and in the presence of space and time dependent electromagnetic fluctuation. We neglect macroscopic drifts due to inhomogeneity and field curvatures, but retain finite Larmor radius effects. (author) 3 refs

  14. Vacuum polarization of the electromagnetic field near a rotating black hole

    International Nuclear Information System (INIS)

    Frolov, V.P.; Zel'nikov, A.I.

    1985-01-01

    The electromagnetic field contribution to the vacuum polarization near a rotating black hole is considered. It is shown that the problem of calculating the renormalized average value of the stress-energy tensor /sup ren/ for the Hartle-Hawking vacuum state at the pole of the event horizon can be reduced to the problem of electro- and magnetostatics in the Kerr spacetime. An explicit expression for /sup ren/ at the pole of the event horizon is obtained and its properties are discussed. It is shown that in the case of a nonrotating black hole the Page-Brown approximation for the electromagnetic stress-energy tensor gives a result which coincides at the event horizon with the exact value of /sup ren/. .AE

  15. Pulsed Electromagnetic Field Assisted in vitro Electroporation: A Pilot Study

    Science.gov (United States)

    Novickij, Vitalij; Grainys, Audrius; Lastauskienė, Eglė; Kananavičiūtė, Rūta; Pamedytytė, Dovilė; Kalėdienė, Lilija; Novickij, Jurij; Miklavčič, Damijan

    2016-09-01

    Electroporation is a phenomenon occurring due to exposure of cells to Pulsed Electric Fields (PEF) which leads to increase of membrane permeability. Electroporation is used in medicine, biotechnology, and food processing. Recently, as an alternative to electroporation by PEF, Pulsed ElectroMagnetic Fields (PEMF) application causing similar biological effects was suggested. Since induced electric field in PEMF however is 2-3 magnitudes lower than in PEF electroporation, the membrane permeabilization mechanism remains hypothetical. We have designed pilot experiments where Saccharomyces cerevisiae and Candida lusitaniae cells were subjected to single 100-250 μs electrical pulse of 800 V with and without concomitant delivery of magnetic pulse (3, 6 and 9 T). As expected, after the PEF pulses only the number of Propidium Iodide (PI) fluorescent cells has increased, indicative of membrane permeabilization. We further show that single sub-millisecond magnetic field pulse did not cause detectable poration of yeast. Concomitant exposure of cells to pulsed electric (PEF) and magnetic field (PMF) however resulted in the increased number PI fluorescent cells and reduced viability. Our results show increased membrane permeability by PEF when combined with magnetic field pulse, which can explain electroporation at considerably lower electric field strengths induced by PEMF compared to classical electroporation.

  16. Plane-wave spectrum approach for the calculation of electromagnetic absorption under near-field exposure conditions

    International Nuclear Information System (INIS)

    Chatterjee, I.; Gandhi, O.P.; Hagmann, M.J.; Riazi, A.

    1980-01-01

    The exposure of humans to electromagnetic near fields has not been sufficiently emphasized by researcher. We have used the plane-wave-spectrum approach to evaluate the electromagnetic field and determine the energy deposited in a lossy, homogeneous, semi-infinite slab placed in the near field of a source leaking radiation. Values of the fields and absorbed energy in the target are obtained by vector summation of the contributions of all the plane waves into which the prescribed field is decomposed. Use of a fast Fourier transform algorithm contributes to the high efficiency of the computations. The numerical results show that, for field distributions that are nearly constant over a physical extent of at least a free-space wavelength, the energy coupled into the target is approximately equal to the resulting from plane-wave exposed

  17. Dynamics of the Solar Wind Electromagnetic Energy Transmission Into Magnetosphere during Large Geomagnetic Storms

    Science.gov (United States)

    Kuznetsova, Tamara; Laptukhov, Alexej; Petrov, Valery

    Causes of the geomagnetic activity (GA) in the report are divided into temporal changes of the solar wind parameters and the changes of the geomagnetic moment orientation relative directions of the solar wind electric and magnetic fields. Based on our previous study we concluded that a reconnection based on determining role of mutual orientation of the solar wind electric field and geomagnetic moment taking into account effects of the Earth's orbital and daily motions is the most effective compared with existing mechanisms. At present a reconnection as paradigma that has applications in broad fields of physics needs analysis of experimental facts to be developed. In terms of reconnection it is important not only mutual orientation of vectors describing physics of interaction region but and reconnection rate which depends from rate of energy flux to those regions where the reconnection is permitted. Applied to magnetosphere these regions first of all are dayside magnetopause and polar caps. Influence of rate of the energy flux to the lobe magnetopause (based on calculations of the Poyting electromagnetic flux component controlling the reconnection rate along the solar wind velocity Pv) on planetary GA (Dst, Kp indices) is investigated at different phases of geomagnetic storms. We study also the rate of energy flux to the polar caps during storms (based on calculations of the Poyting flux vector component along the geomagnetic moment Pm) and its influence on magnetic activity in the polar ionosphere: at the auroral zone (AU,AL indices). Results allow to evaluate contributions of high and low latitude sources of electromagnetic energy to the storm development and also to clear mechanism of the electromagnetic energy transmission from the solar wind to the magnetosphere. We evaluate too power of the solar wind electromagnetic energy during well-known large storms and compare result with power of the energy sources of other geophysical processes (atmosphere, ocean

  18. Energy Resolution Performance of the CMS Electromagnetic Calorimeter

    CERN Document Server

    Adzic, Petar; Almeida, Carlos; Almeida, Nuno; Anagnostou, Georgios; Anfreville, Marc; Anicin, Ivan; Antunovic, Zeljko; Auffray, Etiennette; Baccaro, Stefania; Baffioni, Stephanie; Barney, David; Barone, Luciano; Barrillon, Pierre; Bartoloni, Alessandro; Beauceron, Stephanie; Beaudette, Florian; Bell, Ken W; Benetta, Robert; Bercher, Michel; Berthon, Ursula; Betev, Botjo; Beuselinck, Raymond; Bhardwaj, Ashutosh; Biino, Cristina; Bimbot, Stephane; Blaha, Jan; Bloch, Philippe; Blyth, Simon; Bordalo, Paula; Bornheim, Adolf; Bourotte, Jean; Britton1, D; Brown, Robert M; Brunelière, Renaud; Busson, Philippe; Camporesi, Tiziano; Cartiglia, Nicolo; Cavallari, Francesca; Cerutti, Muriel; Chamont, David; Chang, Paoti; Chang, You-Hao; Charlot, Claude; Chatterji, Sudeep; Chen, E Augustine; Chipaux, Rémi; Choudhary, Brajesh C; Cockerill, David J A; Collard, Caroline; Combaret, Christophe; Cossutti, Fabio; Costantini, Silvia; Da Silva, J C; Dafinei, Ioan; Daskalakis, Georgios; Davatz, Giovanna; Debraine, Alain; Decotigny, David; De Min, Alberto; Deiters, Konrad; Dejardin, Marc; Della Negra, Rodolphe; Della Ricca, Giuseppe; Depasse, Pierre; Descamp, J; Dewhirst, Guy; Dhawan, Satish; Diemoz, Marcella; Dissertori, Günther; Dittmar, Michael; Djambazov, Lubomir; Dobrzynski, Ludwik; Drndarevic, Snezana; Dupanloup, Michel; Dzelalija, Mile; Ehlers, Jan; El-Mamouni, H; Peisert, Anna; Evangelou, Ioannis; Fabbro, Bernard; Faure, Jean-Louis; Fay, Jean; Ferri, Federico; Flower, Paul S; Franzoni, Giovanni; Funk, Wolfgang; Gaillac, Anne-Marie; Gargiulo, Corrado; Gascon-Shotkin, S; Geerebaert, Yannick; Gentit, François-Xavier; Ghezzi, Alessio; Gilly, Jean; Giolo-Nicollerat, Anne-Sylvie; Givernaud, Alain; Gninenko, Sergei; Go, Apollo; Godinovic, Nikola; Golubev, Nikolai; Golutvin, Igor; Gómez-Reino, Robert; Govoni, Pietro; Grahl1, J; Gras1, P; Greenhalgh, Justin; Guillaud, Jean-Paul; Haguenauer, Maurice; Hamel-de-Montechenault, G; Hansen, Magnus; Heath, Helen F; AHill, J; Hobson, Peter R; Holmes, Daniel; Holzner, André; Hou, George Wei-Shu; Ille, Bernard; Ingram, Quentin; Jain, Adarsh; Jarry, Patrick; Jauffret, C; Jha, Manoj; Karar, Akli; Kataria, Sushil Kumar; Katchanov, V A; Kennedy, Bruce W; Kloukinas, Kostas; Kokkas, Panagiotis; Korjik, M; Krasnikov, Nikolai; Krpic, Dragomir; Kyriakis, Aristotelis; Lebeau, Michel; Lecomte, Pierre; Lecoq, Paul; Lemaire, Marie-Claude; Lethuillier, Morgan; Lin, Willis; Lintern, A L; Lister, Alison; Litvin, V; Locci, Elizabeth; Lodge, Anthony B; Longo, Egidio; Loukas, Demetrios; Luckey, D; Lustermann, Werner; Lynch, Clare; MacKay, Catherine Kirsty; Malberti, Martina; Maletic, Dimitrije; Mandjavidze, Irakli; Manthos, Nikolaos; Markou, Athanasios; Mathez, Hervé; Mathieu, Antoine; Matveev, Viktor; Maurelli, Georges; Menichetti, Ezio; Meridiani, Paolo; Milenovic, Predrag; Milleret, Gérard; Miné, Philippe; Mur, Michel; Musienko, Yuri; Nardulli, Alessandro; Nash, Jordan; Neal, Homer; Nédélec, Patrick; Negri, Pietro; Nessi-Tedaldi, Francesca; Newman26, H B; Nikitenko, Alexander; Obertino, Maria Margherita; Ofierzynski, Radoslaw Adrian; Organtini, Giovanni; Paganini, Pascal; Paganoni, Marco; Papadopoulos, Ioannis; Paramatti, Riccardo; Pastrone, Nadia; Pauss, Felicitas; Poilleux, Patrick; Puljak, Ivica; Pullia, Antonino; Puzovic, Jovan; Ragazzi, Stefano; Ramos, Sergio; Rahatlou, Shahram; Rander, John; Ranjan, Kirti; Ravat, Olivier; Raymond, M; Razis, Panos A; Redaelli, Nicola; Renker, Dieter; Reucroft, Steve; Reymond, Jean-Marc; Reynaud, Michel; Reynaud, Serge; Romanteau, Thierry; Rondeaux, Françoise; Rosowsky, André; Rovelli, Chiara; Rumerio, Paolo; Rusack, Roger; Rusakov, Sergey V; Ryan, Matthew John; Rykaczewski, Hans; Sakhelashvili, Tariel; Salerno, Roberto; Santos, Marcelino; Seez, Christopher; Semeniouk, Igor; Sharif, Omar; Sharp, Peter; Shepherd-Themistocleous, Claire; Shevchenko, Sergey; Shivpuri, Ram Krishen; Sidiropoulos, Georgios; Sillou, Daniel; Singovsky, Alexander; Sirois, Yves; Sirunyan, Albert M; Smith, Brian; Smith, Vincent J; Sproston, Martin; Suter, Henry; Swain, John; Tabarelli de Fatis, Tommaso; Takahashi, Maiko; Tapper, Robert J; Tcheremoukhine, Alexandre; Teixeira, Isabel; Teixeira, Joao Paulo; Teller, Olivier; Timlin, Claire; ATriantis, F; Troshin, Sergey; Tyurin, Nikolay; Ueno, Koji; Uzunian, Andrey; Varela, Joao; Vaz-Cardoso, N; Verrecchia, Patrice; Vichoudis, Paschalis; Vigano, S; Viertel, Gert; Virdee, Tejinder; Vlassov, E; Wang, Minzu; Weinstein, Alan; Williams, Jennifer C; Yaselli, Ignacio; Zabi, Alexandre; Zamiatin, Nikolai; Zelepoukine, Serguei; Zeller, Michael E; Zhang, Lin; Zhang, Yawei; Zhu, Kejun; Zhu, Ren-Yuan

    2006-01-01

    The energy resolution performance of the CMS lead tungstate crystal electromagnetic calorimeter is presented. Measurements were made with an electron beam using a fully equipped supermodule of the calorimeter barrel. Results are given both for electrons incident on the centre of crystals and for electrons distributed uniformly over the calorimeter surface. The electron energy is reconstructed in matrices of 3 times 3 or 5 times 5 crystals centred on the crystal containing the maximum energy. Corrections for variations in the shower containment are applied in the case of uniform incidence. The resolution measured is consistent with the design goals.

  19. Interaction of extremely-low-frequency electromagnetic fields with humans

    International Nuclear Information System (INIS)

    Tenforde, T.S.

    1991-07-01

    At a macroscopic level, the effects of extremely low frequency (ELF) electromagnetic fields on humans are well understood based on fundamental physical principles, but far less is known about the nature of the interactions at a cellular or molecular level. Current evidence suggests the effects of ELF on cellular biochemistry are due to interactions with the cell membrane. Elucidation of the mechanism that underlies this transmembrane signaling is critical for a molecular-level understanding of ELF field effects. Further research is also required to clarify a possible link between ELF exposure and increased cancer risk, since estimated ELF exposure in occupational or residential settings is much lower that the levels used in laboratory studies. There is a clear need for additional epidemiological research in which qualitative dosimetry is used to characterize ELF exposure and careful attention is given to possible effects of confounding variables. 24 refs

  20. Circadian neuroendocrine physiology and electromagnetic field studies: Precautions and complexities

    International Nuclear Information System (INIS)

    Warman, G.R.; Tripp, H.M.; Harman, V.L.; Arendt, J.

    2003-01-01

    The suppression of melatonin by exposure to low frequency electromagnetic fields (EMFs) 'the melatonin hypothesis' has been invoked as a possible mechanism through which exposure to these fields may result in an increased incidence of cancer. While the effect of light on melatonin is well established, data showing a similar effect due to EMF exposure are sparse and, where present, are often poorly controlled. The current review focuses on the complexities associated with using melatonin as a marker and the dynamic nature of normal melatonin regulation by the circadian neuroendocrine axis. These are issues which the authors believe contribute significantly to the lack of consistency of results in the current literature. Recommendations on protocol design are also made which, if followed, should enable researchers to eliminate or control for many of the confounding factors associated with melatonin being an output from the circadian clock. (author)

  1. Circadian neuroendocrine physiology and electromagnetic field studies: Precautions and complexities

    Energy Technology Data Exchange (ETDEWEB)

    Warman, G.R.; Tripp, H.M.; Harman, V.L.; Arendt, J

    2003-07-01

    The suppression of melatonin by exposure to low frequency electromagnetic fields (EMFs) 'the melatonin hypothesis' has been invoked as a possible mechanism through which exposure to these fields may result in an increased incidence of cancer. While the effect of light on melatonin is well established, data showing a similar effect due to EMF exposure are sparse and, where present, are often poorly controlled. The current review focuses on the complexities associated with using melatonin as a marker and the dynamic nature of normal melatonin regulation by the circadian neuroendocrine axis. These are issues which the authors believe contribute significantly to the lack of consistency of results in the current literature. Recommendations on protocol design are also made which, if followed, should enable researchers to eliminate or control for many of the confounding factors associated with melatonin being an output from the circadian clock. (author)

  2. Electromagnetically Induced Transparency and Absorption of A Monochromatic Light Controlled by a Radio Frequency Field

    International Nuclear Information System (INIS)

    Cai Xun-Ming

    2015-01-01

    Electromagnetically induced transparency and absorption of a monochromatic light controlled by a radio frequency field in the cold multi-Zeeman-sublevel atoms are theoretically investigated. These Zeeman sublevels are coupled by a radio frequency (RF) field. Both electromagnetically induced transparency and electromagnetically induced absorption can be obtained by tuning the frequency of RF field for both the linear polarization and elliptical polarization monochromatic lights. When the transfer of coherence via spontaneous emission from the excited state to the ground state is considered, electromagnetically induced absorption can be changed into electromagnetically induced transparency with the change of intensity of radio field. The transparency windows controlled by the RF field can have potential applications in the magnetic-field measurement and quantum information processing. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  3. The Norwegian public's perception of risk from electromagnetic fields

    International Nuclear Information System (INIS)

    Maerli, M.B.

    1996-01-01

    A survey with a representative sample of the adult Norwegian population reveals that the public is concerned about the health effects of electromagnetic fields; almost 2/3 of the population regard health effects as a likely consequence if exposed, the level of exposure is regarded as higher today than previously, and a clear majority now consider the fields to be more dangerous than they formerly believed. Despite this general concern, fewer consider personal effects to be probable; approximately one of six reports concern for personal injuries due to the fields. Further, the reported will to act in situations of known exposure from a (hypothetical) power line nearby is high, either by gathering information or putting up shielding against the fields. More concerned parts of the public also show a more committed engagement, including a higher willingness to make economic sacrifices for limiting the fields. There are special features of risk perception across the sample, and gender differences are particularly prominent. Women regard health effects more probable, and respond more strongly to situations of known exposure. People living near to power lines seem to be more aware of the fields, but at the same time cancer is regarded less probable by this group. (author)

  4. Terahertz emission of Bloch oscillators excited by electromagnetic field in lateral semiconductor superlattices

    International Nuclear Information System (INIS)

    Dodin, E.P.; Zharov, A.A.

    2003-01-01

    The effect of the strong high-frequency electromagnetic field on the lateral semiconductor superlattice is considered on the basis of the quasi-classical theory on the electron transport in the self-consistent wave arrangement. It is theoretically identified, that the lateral superlattice in the strong feed-up wave field may emit the terahertz radiation wave trains, which are associated with the periodical excitation of the Bloch oscillations in the superlattice. The conditions, required for the Bloch oscillators radiation observation, are determined. The spectral composition of the radiation, passing through the superlattice, and energy efficiency of multiplying the frequency, related to the Bloch oscillator excitation, are calculated [ru

  5. ELECTROMAGNETIC SAFETY OF ELECTRIC TRANSPORT SYSTEMS: MAIN SOURCES AND PARAMETERS OF MAGNETIC FIELDS

    Directory of Open Access Journals (Sweden)

    N. G. Ptitsyna

    2013-03-01

    Full Text Available Magnetic fields produced by electric drive vehicles may break electromagnetic safety. For electromagnetic safety and electromagnetic compatibility knowledge about characteristics and sources of magnetic fields in the electric transport is necessary. The article deals with analysis of available data about magnetic fields in electric cars and comparison with results of our measurements carried out in the other types of electrified transport systems.

  6. Ionization from short-range potential under action of electromagnetic field of complex configuration

    CERN Document Server

    Rodionov, V N; Kravtsova, G A

    2002-01-01

    The transcendental equation for the complex energy is obtained on the basis of the exactly solvable 3D model of the short-acting potential and the Green time function in the intensive electromagnetic field, constituting the combination of the constant magnetic field and the circular-polarization wave field. The electron quasistationary states parameters in the delta-potential with an account of the action of the intensive external field of complex configuration are calculated. The problem on the possibility of stabilizing the bound states decay of the spinor and scalar particles through the intensive magnetic field is clarified. It is established that the obtained results regime the reexamination of the accepted notion on the stabilizing role of the strong magnetic field by the atoms ionization

  7. Effects of extremely low frequency electromagnetic fields on human beings

    International Nuclear Information System (INIS)

    Lilien, J.L.; Dular, P.; Sabariego, R.; Beauvois, V.; Barbier, P.P.; Lorphevre, R.

    2010-01-01

    Since the early seventies, potential health risks from ELF (Extremely Low frequency electromagnetic Fields) exposure (50 Hz) have been extensively treated in the literature (more than 1000 references registered by WHO (World Health Organisation), 2007). After 30 years of worldwide research, the major epidemiological output is the possible modest increased risk (by a factor 2) of childhood leukaemia in case of a long exposure to an ambient magnetic flux density (B-field) higher than 0.4 μT. However, this fact has not been confirmed by in vivo and in vitro studies. Moreover it has not been validated by any adverse health biological mechanisms neither for adults nor for children. International recommendations (ICNIRP, International Commission on Non-Ionising Radiation Protection) are currently, for general public, not to exceed a B-field of 100 μT (50 Hz) and an E-field of 5 kV/m (50 Hz). Herein, a rough overview of typical values of ELF fields will be presented followed by a brief literature survey on childhood leukaemia and ELF The potential carcinogenic effect of ELF would be linked to electrical disturbances in cell behaviour. The major concern linking child-hood leukaemia and ELF is thus to determine the response of bone marrow cells under ELF fields. With that purpose, transmembrane potential will be targeted and linked to the E-field at that level. This paper is three-folded: (1) the electric interactions between ambient ELF fields and the body are studied both qualitatively and quantitatively. Different sources of internal E-field are analysed and classified according to their potential risk; (2) the hypothesis of contact current is detailed; (3) key actions to undertake are highlighted. Based on the current state of the art and some authors' own developments, this paper proposes simple low cost enhancements of private electrical installations in order to annihilate the major source of potential effects of ELF. (authors)

  8. Impact of the strong electromagnetic field on the QCD effective potential for homogeneous Abelian gluon field configurations

    International Nuclear Information System (INIS)

    Galilo, Bogdan V.; Nedelko, Sergei N.

    2011-01-01

    The one-loop quark contribution to the QCD effective potential for the homogeneous Abelian gluon field in the presence of an external strong electromagnetic field is evaluated. The structure of extrema of the potential as a function of the angles between chromoelectric, chromomagnetic, and electromagnetic fields is analyzed. In this setup, the electromagnetic field is considered as an external one while the gluon field represents domain structured nonperturbative gluon configurations related to the QCD vacuum in the confinement phase. Two particularly interesting gluon configurations, (anti-)self-dual and crossed orthogonal chromomagnetic and chromoelectric fields, are discussed specifically. Within this simplified framework it is shown that the strong electromagnetic fields can play a catalyzing role for a deconfinement transition. At the qualitative level, the present consideration can be seen as a highly simplified study of an impact of the electromagnetic fields generated in relativistic heavy ion collisions on the strongly interacting hadronic matter.

  9. Numerical modelling of GPR electromagnetic fields for locating burial sites

    Directory of Open Access Journals (Sweden)

    Carcione José M.

    2017-01-01

    Full Text Available Ground-penetrating radar (GPR is commonly used for locating burial sites. In this article, we acquired radargrams at a site where a domestic pig cadaver was buried. The measurements were conducted with the ProEx System GPR manufactured by the Swedish company Mala Geoscience with an antenna of 500MHz. The event corresponding to the pig can be clearly seen in the measurements. In order to improve the interpretation, the electromagnetic field is compared to numerical simulations computed with the pseudo-spectral Fourier method. A geological model has been defined on the basis of assumed electromagnetic properties (permittivity, conductivity and magnetic permeability. The results, when compared with the GPR measurements, show a dissimilar amplitude behaviour, with a stronger reflection event from the bottom of the pit. We have therefore performed another simulation by decreasing the electrical conductivity of the body very close to that of air. The comparison improved, showing more reflections, which could be an indication that the body contains air or has been degraded to a certain extent that the electrical resistivity has greatly increased.

  10. Nonlinear optical rectification in vertically coupled InAs/GaAs quantum dots under electromagnetic fields, pressure and temperature effects

    Energy Technology Data Exchange (ETDEWEB)

    Choubani, M., E-mail: mohsenchoubani3@yahoo.fr; Ben Mahrsia, R.; Bouzaiene, L.; Maaref, H.

    2013-12-15

    In this paper we explore the effects of the structural dimensions, applied electromagnetic fields, hydrostatic pressure and temperature on the nonlinear optical rectification (NOR) in Vertically Coupled InAs/GaAs Quantum Dots (VCQDs). The analytical expression of the NOR is analyzed by using the density matrix formalism, the effective mass and the Finite Difference Method (FDM). Obtained results show that the NOR obtained with this coupled system is not a monotonic function of the barrier width, electromagnetic fields, pressure and temperature. Also, calculated results reveal that the resonant peaks of the NOR can be blue-shifted or red-shifted energies depending on the energy of the lowest confined states in the VCQDs structure. In addition, this condition can be controlled by changes in the structural dimensions and the external proofs mentioned above. -- Highlights: • In this paper we explore the effects of the barrier width, applied electromagnetic fields, hydrostatic pressure and temperature on the nonlinear optical rectification (NOR) in Vertically Coupled InAs/GaAs Quantum Dots (VCQDs). • The calculated results reveal that the resonant peaks of the NOR can be blue-shifted to large photon energies or red-shifted to lower photon energies. • In this paper, all parameters: electromagnetic fields, pressure and temperature effects are introduced and investigated. • The resonant energy and the magnitude of the NOR are controlled and adjusted.

  11. Membrane viewpoint on black holes: Dynamical electromagnetic fields near the horizon

    International Nuclear Information System (INIS)

    Macdonald, D.A.; Suen, W.

    1985-01-01

    This paper is part of a series of papers with the aim of developing a complete self-consistent formalism for the treatment of electromagnetic and gravitational fields in the neighborhood of a black-hole horizon. In this membrane formalism, the horizon is treated as a closed two-dimensional membrane lying in a curved three-dimensional space, and endowed with familiar physical properties such as entropy and temperature, surface pressure and viscosity, and electrical conductivity, charge, and current. This paper develops the concept of the ''stretched horizon,'' which will be vital for both the electromagnetic and gravitational aspects of the formalism, and it presents several model problems illustrating the interaction of dynamical electromagnetic fields with stationary black-hole horizons: The field of a test charge in various states of motion outside the Schwarzschild horizon is analyzed in the near-horizon limit, where the spatial curvature may be ignored and the metric may be approximated by that of Rindler. This analysis elucidates the influence of the horizon on the shapes and motions of electric and magnetic field lines when external agents move the field lines in arbitrary manners. It also illustrates how the field lines interact with the horizon's charge and current to produce an exchange of energy and momentum between the external agent and the horizon. A numerical calculation of the dynamical relaxation of a magnetic field threading a Schwarzschild black hole is also presented, illustrating the ''cleaning'' of a complicated field structure by a black-hole horizon, and elucidating the constraints on the location of the stretched horizon

  12. Strong interactions and electromagnetism in low-energy hadron physics

    International Nuclear Information System (INIS)

    Kubis, B.

    2002-10-01

    In the present work, we study various aspects of the entanglement of the strong and electromagnetic interactions as it is manifest in low-energy hadron physics. In the framework of chiral perturbation theory, two aspects are investigated: the test of the structure of baryons as probed by external electromagnetic currents, and the modification of reactions mediated by the strong interactions in the presence of internal (virtual) photons. In the first part of this work, we study the electromagnetic form factors of nucleons and the ground state baryon octet, as well as strangeness form factors of the nucleon. Emphasis is put on the comparison of a new relativistic scheme for the calculation of loop diagrams to the heavy-baryon formalism, and on the convergence of higher-order corrections in both schemes. The new scheme is shown to yield both a phenomenologically more successful description of the data and better convergence behaviour. In the second part, we study isospin violation in pion-kaon scattering as mediated by virtual photon effects and the light quark mass difference. This investigation is of particular importance for the extraction of scattering lengths from measurements of lifetime and energy levels in pion-kaon atoms. The isospin breaking corrections are shown to be small and sufficiently well under control. (orig.)

  13. Hybrid acoustic energy harvesting using combined electromagnetic and piezoelectric conversion

    Science.gov (United States)

    Khan, Farid Ullah; Izhar

    2016-02-01

    This paper reports a novel hybrid acoustic energy harvester. The harvester utilizes both the electromagnetic and piezoelectric conversion mechanisms simultaneously to convert the ambient acoustical noise into electrical power for self-powered wireless sensor nodes. The proposed harvester is comprised of a Helmholtz resonator, two magnets mounted on a piezoelectric plate, and a wound coil located under the magnets. The harvester is characterized both under harmonic and real random acoustical excitations. In-lab, under harmonic acoustical excitation at a sound pressure level of 130 dB and frequency of 2.1 kHz, an optimum power of 2.86 μW (at 114 Ω optimum load) is obtained from electromagnetic conversion and 50 μW (at 1000 Ω optimum load) is generated by the piezoelectric harvester's part. Moreover, in real acoustical environment of a domestic electric generator the peak voltages of 40 and 123 mV are produced by the electromagnetic and piezoelectric portions of the acoustic energy harvester.

  14. Motionally-induced electromagnetic fields generated by idealized ocean currents

    Science.gov (United States)

    Tyler, R. H.; Mysak, L. A.

    Using the induction equation, we investigate the generation of electromagnetic fields by the motional electromagnetic induction due to ocean currents. In this paper, solutions are presented for a linear induction equation for the magnetic flux density vector which contains prescribed time-independent ocean current and conductivity fields. Once the magnetic flux density is known, the electric field and electric current density are easily obtained by differentiation. Solutions are given for several examples of idealized flow which include: 1) Vertically and horizontally sheared plane-parallel flow with depth-dependent conductivity; 2) A simple Stommel circulation gyre; and 3) Symmetric gyres. The results indicate that typical ocean current features induce magnetic fields with magnitudes reaching 100's of nT within the water and about 1-10 outside of the water. For the case of a field of gyres, the ocean-induced magnetic fields decay away from the ocean on spatial scales set by the horizontal scale of the ocean feature. At the altitudes of magnetic field satellite surveys, ocean-induced magnetic fields may retain values of a few nT, which are strong enough to be detected. Thus it is concluded that satellite observations of the earth's main magnetic field and, in particular, the observed temporal variations, could be affected by the ocean circulation. Summary and discussion In Section 3, we found exact solutions to the induction equation for idealized flows. The results gave magnitudes of about tens to hundreds of nT for the magnetic fields bH, about 10-5 V/m for the electric fields E, and about 10-5 A/m2 for the electric current density J induced by the ocean currents. These figures are in general agreement with the calculations of Lilley et al. (1993). In Section 4.2 we obtained solutions for the magnetic field above the ocean surface for the case of a Stommel gyre and a field of symmetric gyres. It was found in the last case that ocean gyres with a total transport

  15. Electromagnetic energy harvesting from a dual-mass pendulum oscillator

    Science.gov (United States)

    Wang, Hongyan; Tang, Jiong

    2016-04-01

    This paper presents the analysis of a type of vibration energy harvester composed of an electromagnetic pendulum oscillator combined to an elastic main structure. In this study, the elastic main structure connected to the base is considered as a single degree-of-freedom (DOF) spring-mass-damper subsystem. The electromagnetic pendulum oscillator is considered as a dual-mass two-frequency subsystem, which is composed of a hollow bar with a tip winded coil and a magnetic mass with a spring located in the hollow bar. As the pendulum swings, the magnetic mass can move along the axial direction of the bar. Thus, the relative motion between the magnet and the coil induces a wire current. A mathematical model of the coupled system is established. The system dynamics a 1:2:1 internal resonance. Parametric analysis is carried out to demonstrate the effect of the excitation acceleration, excitation frequency, load resistance, and frequency tuning parameters on system performance.

  16. Retraction: Evaluation of carcinogenic effects of electromagnetic fields (EMF).

    Science.gov (United States)

    Mehic, Bakir

    2010-11-01

    The Editor-in-chief of the Bosnian Journal of Basic Medical Sciences has decided to retract the article from Bayazit V et al. [1] entitled as: "Evaluation of carcinogenic effects of electromagnetic fields (EMF)" published in Bosn J Basic Med Sci. 2010 Aug;10(3):245-50. After the editorial office was alerted of possible plagiarism in the article, it conducted thorough investigation and concluded that the article apparently represents plagiarized material from two World Health Organization reports, one European Commission report and other sources. Since this is considered scientific plagiarism and scientific misconduct, Editor-in-chief has decided to withdraw the article. The authors have agreed with the editorial office decision.

  17. The generalized canonical formalism for the electromagnetic field

    CERN Document Server

    Constantinescu, R

    2001-01-01

    The possibility of the Hamiltonian description of the electromagnetic field as a constrained dynamical system is analyzed. We use the BRST technique and we study the consequences of the implementation of a third order symmetry, that is a symmetry related to the symplectic group sp(3). The connection between this larger symmetry and the standard BRST one is also discussed. The following results are underlined: building a generalized BRST symmetry appears as possible; the standard and the sp(2) theories prove themselves as the first two stages of this global theory. By it, a more extended symmetry asks for a larger ghost spectrum and, so, more nonminimal terms can be employed in the gauge fixing procedure. (authors)

  18. Electromagnetic field pretreatment of Sinapis alba seeds improved cadmium phytoextraction.

    Science.gov (United States)

    Bulak, Piotr; Lata, Lesia; Plak, Andrzej; Wiącek, Dariusz; Strobel, Wacław; Walkiewicz, Anna; Pietruszewski, Stanisław; Bieganowski, Andrzej

    2018-03-21

    It was hypothesized that electromagnetic field (EMF) pretreatment of white mustard (Sinapis alba L.) seeds could increase the accumulation of non-essential, pollutant heavy metals such as cadmium (Cd) in shoots. Seeds of white mustard were treated with either 60 or 120 mT of alternating EMF (50 Hz) for 1 minute and then grown in a Petri dish in the presence of Cd, in comparison to the control (seeds grown without EMF pretreatment). Biomass production and content of calcium (Ca) and Cd in seedling shoots were measured. The Cd content in shoots from the EMF-treated seeds was higher in both variants than in the control (by 73% and 78%, respectively; p phytoextraction, but more research is needed.

  19. Resonant scattering in the presence of an electromagnetic field

    International Nuclear Information System (INIS)

    Rosenberg, L.

    1983-01-01

    The theory of resonant reactions, in the projection-operator formulation of Feshbach, is generalized to account for the presence of an external electromagnetic field. The theory is used as the basis for the construction of low-frequency approximations for the transition amplitude. Results obtained here for scattering in a laser field confirm earlier versions of the low-frequency approximation when the resonances are isolated. However, if there are several closely spaced resonances additional terms must be included (their importance magnified by the appearance of near singularities) which account for the effect of radiative transitions between pairs of nearly degenerate resonant states. The weak-field limit of this result yields a low-frequency approximation for single-photon spontaneous bremsstrahlung which, through the inclusion of correction terms associated with closely spaced resonances, provides an improvement over the Feshbach-Yennie version derived some time ago. A separate treatment is required to deal with the limiting case of a static external field and this is worked out here in the context of a time-dependent formulation of the scattering problem. Linear and quadratic Stark splitting of the resonance positions, and resonance broadening due to the tunneling mechanism, are expected to play a significant role in the static limit and these effects are included in the approximation derived here for the transition amplitude

  20. Fast propagation of electromagnetic fields through graded-index media.

    Science.gov (United States)

    Zhong, Huiying; Zhang, Site; Shi, Rui; Hellmann, Christian; Wyrowski, Frank

    2018-04-01

    Graded-index (GRIN) media are widely used for modeling different situations: some components are designed considering GRIN modulation, e.g., multi-mode fibers, optical lenses, or acousto-optical modulators; on the other hand, there are other components where the refractive-index variation is undesired due to, e.g., stress or heating; and finally, some effects in nature are characterized by a GRIN variation, like turbulence in air or biological tissues. Modeling electromagnetic fields propagating in GRIN media is then of high importance for optical simulation and design. Though ray tracing can be used to evaluate some basic effects in GRIN media, the field properties are not considered and evaluated. The general physical optics techniques, like finite element method or finite difference time domain, can be used to calculate fields in GRIN media, but they need great numerical effort or may even be impractical for large-scale components. Therefore, there still exists a demand for a fast physical optics model of field propagation through GRIN media on a large scale, which will be explored in this paper.

  1. Radiofrequency electromagnetic fields in the Cookridge area of Leeds

    International Nuclear Information System (INIS)

    Fuller, K.; Gulson, A.D.; Judd, P.M.; Lowe, A.J.; Shaw, J.

    2002-01-01

    On the 8 and 9 May 2002 representatives of the National Radiological Protection Board (NRPB) performed a radiofrequency electromagnetic field survey in the Cookridge area of Leeds in order to assess exposure to radio signals from transmitters mounted on a water tower/a lattice tower and a radio station tower. Guidelines on limiting exposure to radio signals have been published by NRPB and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). These guidelines are designed to prevent established adverse effects on human health. During this survey, the total exposures due to all radio signals from 30 MHz to 18000 MHz (18 GHz) were measured. This frequency range was chosen as it includes mobile phone base station transmissions, which are at around 900 and 1800 MHz and super high frequency (SHF) transmissions from most of the large microwave dish antennas mounted on the towers. In addition, other major sources of radiofrequency electromagnetic fields in the environment such as broadcast radio and television transmissions are included in this range. Measurements of power density were made at eight locations in the vicinity of the transmitter sites. Comparison of the measurements with the guidelines showed that the total exposure from radio signals measured between 30 MHz and 18 GHz ranged from 0.26 millionths (0.000026%) to 190 millionths (0.019%) of the NRPB investigation level and from 1.6 millionths (0.00016%) to 1400 millionths (0.14%) of the ICNIRP reference level for exposure of the general public. All the measured exposures are therefore many times below guideline levels and are not considered hazardous. (author)

  2. High Frequency Electromagnetic Field Induces Lipocalin 2 Expression in

    Directory of Open Access Journals (Sweden)

    Amaneh Mohammadi Roushandeh

    2010-06-01

    Full Text Available Objective(sNeutrophil gelatinase-associated lipocalin (NGAL/Lcn2, comprise a group of small extracellular proteins with a common β-sheet-dominated 3-dimensional structure. In the past, it was assumed that the predominant role of lipocalin was acting as transport proteins. Recently it has been found that oxidative stress induces Lcn2 expression. It has been also proved that electromagnetic field (EMF produces reactive oxygen species (ROS in different tissues. Expression of Lcn2 following exposure to electromagnetic field has been investigated in this study. Materials and MethodsBalb/c mice (8 weeks old were exposed to 3 mT, 50 HZ EMF for 2 months, 4 hr/day. Afterwards, the mice were sacrificed by cervical dislocation and livers were removed. The liver specimens were stained with Haematoxylin- Eosin (H&E and analyzed under an optical microscope. Total RNA was extracted from liver and reverse transcription was performed by SuperScript III reverse transcriptase with 1 µg of total RNA. Assessment of Lcn2 expression was performed by semiquantitative and real time- PCR.ResultsThe light microscopic studies revealed that the number of lymphocyte cells was increased compared to control and dilation of sinosoids was observed in the liver. Lcn2 was up-regulated in the mice exposed to EMF both in mRNA and protein levels.ConclusionTo the extent of our knowledge, this is the first report dealing with up-regulation of Lcn2 in liver after exposure to EMF. The up-regulation might be a compensatory response that involves cell defense pathways and protective effects against ROS. However, further and complementary studies are required in this regards.

  3. Superconducting magnetic energy storage and superconducting self-supplied electromagnetic launcher

    Science.gov (United States)

    Ciceron, Jérémie; Badel, Arnaud; Tixador, Pascal

    2017-10-01

    Superconductors can be used to build energy storage systems called Superconducting Magnetic Energy Storage (SMES), which are promising as inductive pulse power source and suitable for powering electromagnetic launchers. The second generation of high critical temperature superconductors is called coated conductors or REBCO (Rare Earth Barium Copper Oxide) tapes. Their current carrying capability in high magnetic field and their thermal stability are expanding the SMES application field. The BOSSE (Bobine Supraconductrice pour le Stockage d'Energie) project aims to develop and to master the use of these superconducting tapes through two prototypes. The first one is a SMES with high energy density. Thanks to the performances of REBCO tapes, the volume energy and specific energy of existing SMES systems can be surpassed. A study has been undertaken to make the best use of the REBCO tapes and to determine the most adapted topology in order to reach our objective, which is to beat the world record of mass energy density for a superconducting coil. This objective is conflicting with the classical strategies of superconducting coil protection. A different protection approach is proposed. The second prototype of the BOSSE project is a small-scale demonstrator of a Superconducting Self-Supplied Electromagnetic Launcher (S3EL), in which a SMES is integrated around the launcher which benefits from the generated magnetic field to increase the thrust applied to the projectile. The S3EL principle and its design are presented. Contribution to the topical issue "Electrical Engineering Symposium (SGE 2016)", edited by Adel Razek

  4. Maxwell-Faraday Stresses in Electromagnetic Fields and the Self-Force on a Uniformly Accelerating Point Charge

    Science.gov (United States)

    Rowland, D. R.

    2007-01-01

    The physical analysis of a uniformly accelerating point charge provides a rich problem to explore in advanced courses in electrodynamics and relativity since it brings together fundamental concepts in relation to electromagnetic radiation, Einstein's equivalence principle and the inertial mass of field energy in ways that reveal subtleties in each…

  5. Propagation of electromagnetic radiation in a random field of gravitational waves and space radio interferometry

    International Nuclear Information System (INIS)

    Braginsky, V.B.; Kardashev, N.S.; Polnarev, A.G.; Novikov, I.D.

    1989-12-01

    Propagation of an electromagnetic wave in the field of gravitational waves is considered. Attention is given to the principal difference between the electromagnetic wave propagation in the field of random gravitational waves and the electromagnetic wave propagation in a medium with a randomly-inhomogeneous refraction index. It is shown that in the case of the gravitation wave field the phase shift of an electromagnetic wave does not increase with distance. The capability of space radio interferometry to detect relic gravitational waves as well as gravitational wave bursts of non cosmological origin are analyzed. (author). 64 refs, 2 figs

  6. Multiphoton processes for atoms in intense electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Collins, L.A.; Abdallah, J.; Csanak, G.

    1995-12-31

    Lasers from table-top to giant ICF facilities that produce intense electromagnetic fields (10{sup 14}-10{sup 21} W/cm{sup 2}) have become important tools in probing the intricate nature of matter-radiation interactions. At such intensities, the laser field equals or exceeds that which binds electrons to an atom or molecule, and a new realm of physics opens in which perturbation theory may no longer suffice. We are developing several sophisticated techniques for treating atoms in such a regime, concentrating on two-photon X-ray absorption in intermediate-weight atoms and on laser-assisted electron-atom collisions. We perform most calculations in a time-independent frame in which field-free scattering formalisms can be invoked. We also investigate time-dependent methods in order to study transient effects. This is the final report of a three-year Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL).

  7. A metamaterial electromagnetic energy rectifying surface with high harvesting efficiency

    Directory of Open Access Journals (Sweden)

    Xin Duan

    2016-12-01

    Full Text Available A novel metamaterial rectifying surface (MRS for electromagnetic energy capture and rectification with high harvesting efficiency is presented. It is fabricated on a three-layer printed circuit board, which comprises an array of periodic metamaterial particles in the shape of mirrored split rings, a metal ground, and integrated rectifiers employing Schottky diodes. Perfect impedance matching is engineered at two interfaces, i.e. one between free space and the surface, and the other between the metamaterial particles and the rectifiers, which are connected through optimally positioned vias. Therefore, the incident electromagnetic power is captured with almost no reflection by the metamaterial particles, then channeled maximally to the rectifiers, and finally converted to direct current efficiently. Moreover, the rectifiers are behind the metal ground, avoiding the disturbance of high power incident electromagnetic waves. Such a MRS working at 2.45 GHz is designed, manufactured and measured, achieving a harvesting efficiency up to 66.9% under an incident power density of 5 mW/cm2, compared with a simulated efficiency of 72.9%. This high harvesting efficiency makes the proposed MRS an effective receiving device in practical microwave power transmission applications.

  8. A metamaterial electromagnetic energy rectifying surface with high harvesting efficiency

    Science.gov (United States)

    Duan, Xin; Chen, Xing; Zhou, Lin

    2016-12-01

    A novel metamaterial rectifying surface (MRS) for electromagnetic energy capture and rectification with high harvesting efficiency is presented. It is fabricated on a three-layer printed circuit board, which comprises an array of periodic metamaterial particles in the shape of mirrored split rings, a metal ground, and integrated rectifiers employing Schottky diodes. Perfect impedance matching is engineered at two interfaces, i.e. one between free space and the surface, and the other between the metamaterial particles and the rectifiers, which are connected through optimally positioned vias. Therefore, the incident electromagnetic power is captured with almost no reflection by the metamaterial particles, then channeled maximally to the rectifiers, and finally converted to direct current efficiently. Moreover, the rectifiers are behind the metal ground, avoiding the disturbance of high power incident electromagnetic waves. Such a MRS working at 2.45 GHz is designed, manufactured and measured, achieving a harvesting efficiency up to 66.9% under an incident power density of 5 mW/cm2, compared with a simulated efficiency of 72.9%. This high harvesting efficiency makes the proposed MRS an effective receiving device in practical microwave power transmission applications.

  9. Occupational exposure to electromagnetic fields and sex-differential risk of uveal melanoma

    DEFF Research Database (Denmark)

    Behrens, Thomas Flensted; Lynge, Elsebeth; Cree, Ian

    2010-01-01

    The association between occupational exposure to electromagnetic fields (EMF) and the risk of uveal melanoma was investigated in a case-control study in nine European countries.......The association between occupational exposure to electromagnetic fields (EMF) and the risk of uveal melanoma was investigated in a case-control study in nine European countries....

  10. Bianchi type-I model with conformally invariant scalar and electromagnetic field

    International Nuclear Information System (INIS)

    Accioly, A.J.; Vaidya, A.N.; Som, M.M.

    1983-01-01

    A Bianchi type-I exact solution of the Einstein theory representing the homogeneous anisotropic models with the electromagnetic field and the conformally invariant scalar field is studied. The solution contains Kasner model, pure electromagnetic and pure scalar models as special cases. It is found that the models evolve from an initial Kasner type to a final open Friedmann type universe. (Author) [pt

  11. Sensitivity of the near-surface vertical electric field land Controlled-Source Electromagnetic monitoring

    NARCIS (Netherlands)

    Schaller, A.M.; Hunziker, J.W.; Streich, R.; Drijkoningen, G.G.

    2014-01-01

    We investigate potential benefits of measuring the vertical electric field component in addition to the routinely measured horizontal electric field components in onshore time-lapse controlled-source electromagnetics. Synthetic electromagnetic data based on a model of the Schoonebeek onshore oil

  12. Effects of electromagnetic fields on human beings. Technical aspects and research results. - Regulations

    International Nuclear Information System (INIS)

    Kieback, D.

    1996-01-01

    The present brochure of the Professional Association for Fine Mechanics and Electrical Engineering gives a selective account on the effects of electromagnetic fields on human beings. The second part deals with regulations for safety and health protection at working places exposed to electromagnetic fields. (VHE) [de

  13. Occupational exposure to electromagnetic fields, leukemia and brain cancer: update of two meta-analysis

    International Nuclear Information System (INIS)

    Anon.

    2008-01-01

    This new meta-analysis found a slight increase in the risk of brain cancer and of leukemia in populations occupationally exposed to electromagnetic fields. it does not, however, support the hypothesis that electromagnetic fields have an effect on these cancers. (author)

  14. Assessment of occupational exposure to radio frequency electromagnetic fields

    Directory of Open Access Journals (Sweden)

    Halina Aniołczyk

    2015-06-01

    Full Text Available Background: European Union Directive 2013/35/UE provides for the implementation of EU regulations into national legislation. Our aim is to assess actual health hazards from radiofrequency electromagnetic field (RF EMF (range: 100 kHz – 300 GHz and indicate workplaces with the highest risk to employee health. Material and Methods: Data from measurements of RF EMF performed by the Laboratory of Electromagnetic Hazards in Nofer Institute of Occupational Medicine (Łódź, Poland were analyzed. The analysis covered the results of electric field intensity (E for over 450 selected items. The ranges of protection zones and the extent to which maximum admissible intensity (MAI values were also analyzed. The determinations and measurements of EMF in the work environment met the requirements of Polish Standard, while Polish regulations on the MAI values were used as the criterion for the assessment of the exposure. Results: The highest values of E field intensity at workplaces were measured for: electrosurgery, to 400 V/m, and short-wave diathermy units, to 220 V/m, dielectric welders to 240 V/m, within the FM radio antenna systems, to 180 V/m. The widest protection zones were noted for prototype research instruments, short-wave diathermy units, and dielectric welders. The most excessive (up to 12-fold MAI values were recorded for dielectric welders, short-wave diathermy units (up to 11-fold and microwave diathermy units (up to 8-fold. Conclusions: Our results have confirmed the high RF EMF values for physiotherapists, operators of dielectric welders, and mast maintenance workers in radio communication facilities (especially radio and TV broadcasting stations. Med Pr 2015;66(2:199–212

  15. Scientific days on electromagnetic fields: from dosimetry to human health - Conference proceedings

    International Nuclear Information System (INIS)

    Wiart, J.; Ghanmi, A.; Picon, O.; Conil, E.; Varsier, N.; Hadjem, A.; Sudret, B.; Magne, I.; Souques, M.; Gaudaire, F.; De Seze, R.; Jawad, O.; Lautru, D.; Dricot, J.M.; Horlin, F.; De Doncker, P.; Drissaoui, A.; Musy, F.; Nicolas, L.; Perrussel, R.; Scorretti, R.; Voyer, D.; Jala, M.; Moulines, E.; Levy-Leduc, C.; Mahfouz, Z.; Gati, A.; Fouad Hanna, V.; Leveque, P.; Arnaud-Cormos, D.; Zhadobov, M.; Jarrige, P.; Gaborit, G.; Kohler, S.; Ticaud, N.; Duvillaret, L.; Guelilia, Z.; Loison, R.; Gillard, R.; Laisne, A.; Favet, D.; Benadhira, R.; Mir, L.; Nadi, M.; Kourtiche, D.; Gazeau, F.; Wilhelm, C.; Delemotte, L.; Breton, M.; Tarek, M.; Marc-Vergnes, J.P.; Yardin, C.; Perrin, A.; Le Drean, Y.; Sauleau, R.; Lambrozo, J.; Selmaoui, B.; Ghosn, R.; Thuroczy, G.; Villegier, A.S.; Loos, N.; Brenet-Dufour, V.; Liabeuf, S.; Bach, V.; Moretti, D.; Lewis, N.; Garenne, A.; Poulletier De Gannes, F.; Haro, E.; Lagroye, I.; Bornat, Y.; Boutaib, Y.; Saighi, S.; Renaud, S.; Veyre, B.; Schuz, J.; Deltour, I.; Van Deventer, E.; Vecchia, P.; Merckel, O.; Bellaouel, A.; Demaret, P.; Donati, P.; Jovanovic, D.; Chauvin, S.; Desreumaux, J.P.; Fouquet, L.; Picard, D.; Massardier-Pilonchery, A.; Hours, M.; Bergeret, A.; Person, C.; Toutain, Y.; Butet, R.; Berrahma, K.; Balderelli, I.; Stelmaszyk, V.; Cretallaz, C.; Lamproglou, I.; Amourette, C.; Diserbo, M.; Fauquette, W.; Martigne, P.; Collin, A.; Lagroye, I.; Ait Aissa, S.; Hurtier, A.; Taxile, M.; Le Montagner, L.; Athane, A.; Duleu, S.; Percherancier, Y.; Geffard, M.; Ruffie, G.; Billaudel, B.; Veyret, B.; Pelletier, A.; Delanaud, S.; Libert, J.P.; Schunck, T.; Bieth, F.; Soubere Mahamoud, Y.; Le Quement, C.; Ferrand, G.; Le Guevel, R.; Carton, P.H.; Luong, M.; Tanvir, S.; Selmaoui, B.; Silva Pires-Antonietti, V.; Sonnet, P.; Pulvin, S.; Kuster, O.; Tetelin, C.

    2012-04-01

    This document brings together the available presentations (articles and slides) given at the URSI scientific days on electromagnetic fields: dosimetry, peoples' exposure, biological and health risks, risk management, and medical uses. 48 presentations are compiled in this document and deal with: 1 - Stochastic dosimetry: variability challenge; 2 - How to estimate the exposure to 50/60 Hz magnetic field in an epidemiological study?; 3 - Joint analysis of population exposure and radio coverage of GSM and UMTS mobile phone networks; 4 - Study of the specific energy absorption rate (SAR) sensitiveness to phone positions near the head for 2 GSM mobile phones; 5 - Statistical Study of SAR under Wireless Channel - Exposure in Indoor Environment; 6 - Uncertainty propagation in numerical dosimetry: how to reduce calculation costs?; 7 - Use of a simplified pregnant woman model for foetus exposure analysis; 8 - SAR estimation using multi-exposure with a mobile phone; 9 - State-of-the-art in experimental dosimetry (RF and pulses); 10 - Mm-waves dosimetry: issues, stakes and actual solutions; 11 - Use of DG-FDTD for a dosimetry calculation in a strongly multi-scale problem: determination of the eye-SAR near a HF/VHF vehicle-borne source; 12 - Dosimetric measurements with a fiber-type electro-optical sensor; 13 - Partial experimental evaluation of basic restrictions in the HF/VHF range; 14 - Repetitive trans-cranial magnetic stimulation Stimulation (rTMS) in psychiatry: present day situation and perspectives; 15 - Medical applications of electric fields; 16 - Measurements for life: new perspectives? 17 - Nano-particles and magnetic stimuli for medical imaging and therapy; 18 - Molecular Insights into electroporation and siRNA electro-transfer through model cell membranes; 19 - State of knowledge on electromagnetic fields hypersensitivity (HS-CEM); 20 - Experimentation methodology: from results to interpretation; 22 - Mm waves - update on biological effects at 40-60 GHz; 23

  16. Exposure to electromagnetic fields aboard high-speed electric multiple unit trains.

    Science.gov (United States)

    Niu, D; Zhu, F; Qiu, R; Niu, Q

    2016-01-01

    High-speed electric multiple unit (EMU) trains generate high-frequency electric fields, low-frequency magnetic fields, and high-frequency wideband electromagnetic emissions when running. Potential human health concerns arise because the electromagnetic disturbances are transmitted mainly into the car body from windows, and from there to passengers and train staff. The transmission amount and amplitude distribution characteristics that dominate electromagnetic field emission need to be studied, and the exposure level of electromagnetic field emission to humans should be measured. We conducted a series of tests of the on board electromagnetic field distribution on several high-speed railway lines. While results showed that exposure was within permitted levels, the possibility of long-term health effects should be investigated.

  17. Hyperthermic effect of magnetic nanoparticles under electromagnetic field

    Directory of Open Access Journals (Sweden)

    Giovanni Baldi

    2009-06-01

    Full Text Available Magnetic nanoparticles have attracted increasingly attention due to their potential applications in many industrial fields, even extending their use in biomedical applications. In the latter contest the main features of magnetic nanoparticles are the possibility to be driven by external magnetic fields, the ability to pass through capillaries without occluding them and to absorb and convert electromagnetic radiation in to heat (Magnetic Fluid Hyperthermia. The main challenges of the current works on hyperthermia deal with the achievement of highly efficiency magnetic nanoparticles, the surface grafting with ligands able to facilitate their specific internalisation in tumour cells and the design of stealth nanocomposites able to circulate in the blood compartment for a long time. This article presents the synthesis of cobalt ferrite nanoparticles dispersed in diethylene glycol via the so called polyol strategy and the crystal size control through successive synthesis steps. Preliminary heat dissipation evaluations on the prepared samples were carried out and the question of how particles sizes affect their magnetic and hyperthermic properties was addressed as well. Furthermore we will present how surface chemistry can be modified in order to change the dispersity of the product without affecting magnetic and hyperthermic properties.

  18. Electromagnetically induced transparency resonances inverted in magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Sargsyan, A.; Sarkisyan, D., E-mail: davsark@yahoo.com, E-mail: david@ipr.sci.am [National Academy of Sciences of Armenia, Institute for Physical Research (Armenia); Pashayan-Leroy, Y.; Leroy, C. [Université de Bourgogne-Dijon, Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR CNRS (France); Cartaleva, S. [Bulgarian Academy of Sciences, Institute of Electronics (Bulgaria); Wilson-Gordon, A. D. [Bar-Ilan University Ramat Gan, Department of Chemistry (Israel); Auzinsh, M. [University of Latvia, Department of Physics (Latvia)

    2015-12-15

    The phenomenon of electromagnetically induced transparency (EIT) is investigated in a Λ-system of the {sup 87}Rb D{sub 1} line in an external transverse magnetic field. Two spectroscopic cells having strongly different values of the relaxation rates γ{sub rel} are used: an Rb cell with antirelaxation coating (L ∼ 1 cm) and an Rb nanometric- thin cell (nanocell) with a thickness of the atomic vapor column L = 795 nm. For the EIT in the nanocell, we have the usual EIT resonances characterized by a reduction in the absorption (dark resonance (DR)), whereas for the EIT in the Rb cell with an antirelaxation coating, the resonances demonstrate an increase in the absorption (bright resonances (BR)). We suppose that such an unusual behavior of the EIT resonances (i.e., the reversal of the sign from DR to BR) is caused by the influence of an alignment process. The influence of alignment strongly depends on the configuration of the coupling and probe frequencies as well as on the configuration of the magnetic field.

  19. Bray–Liebhafsky oscillatory reaction in the radiofrequency electromagnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Stanisavljev, Dragomir R., E-mail: dragisa@ffh.bg.ac.rs [Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, P.O. Box 473, 11001 Belgrade (Serbia); Velikić, Zoran [Institute of Physics, University of Belgrade, Pregrevica 118, Zemun (Serbia); Veselinović, Dragan S.; Jacić, Nevena V.; Milenković, Maja C. [Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, P.O. Box 473, 11001 Belgrade (Serbia)

    2014-09-30

    Highlights: • Oscillatory Bray–Liebhafsky reaction is coupled with the radiofrequency radiation. • The effects of radiofrequency field on oscillatory parameters are investigated. • Radiofrequency power of up to the 0.2 W did not produced observable changes. • The explanation related with dissipative and capacitive effects is given. • Open the possibility of investigations of reactive effects on biological systems. - Abstract: Oscillatory Bray–Liebhafsky (BL) reaction is capacitively coupled with the electromagnetic radiation in the frequency range 60–110 MHz. Because of the specific reaction dynamics characterized by several characteristic parameters (induction period, period between chemical oscillations and their amplitude) it served as a good model system for the investigation of the effects of radiofrequent (RF) radiation. RF power of up to 0.2 W did not produce observable changes of the BL reaction parameters in the limit of the experiment reproductivity. Results indicate that, under the given experimental conditions, both dissipative and reactive properties of the solution are not considerably coupled with the RF electrical field.

  20. Self-consistent evolution of plasma discharge and electromagnetic fields in a microwave pulse compressor

    International Nuclear Information System (INIS)

    Shlapakovski, A. S.; Beilin, L.; Krasik, Ya. E.; Hadas, Y.; Schamiloglu, E.

    2015-01-01

    Nanosecond-scale evolution of plasma and RF electromagnetic fields during the release of energy from a microwave pulse compressor with a plasma interference switch was investigated numerically using the code MAGIC. The plasma was simulated in the scope of the gas conductivity model in MAGIC. The compressor embodied an S-band cavity and H-plane waveguide tee with a shorted side arm filled with pressurized gas. In a simplified approach, the gas discharge was initiated by setting an external ionization rate in a layer crossing the side arm waveguide in the location of the electric field antinode. It was found that with increasing ionization rate, the microwave energy absorbed by the plasma in the first few nanoseconds increases, but the absorption for the whole duration of energy release, on the contrary, decreases. In a hybrid approach modeling laser ignition of the discharge, seed electrons were set around the electric field antinode. In this case, the plasma extends along the field forming a filament and the plasma density increases up to the level at which the electric field within the plasma decreases due to the skin effect. Then, the avalanche rate decreases but the density still rises until the microwave energy release begins and the electric field becomes insufficient to support the avalanche process. The extraction of the microwave pulse limits its own power by terminating the rise of the plasma density and filament length. For efficient extraction, a sufficiently long filament of dense plasma must have sufficient time to be formed

  1. Self-consistent evolution of plasma discharge and electromagnetic fields in a microwave pulse compressor

    Science.gov (United States)

    Shlapakovski, A. S.; Beilin, L.; Hadas, Y.; Schamiloglu, E.; Krasik, Ya. E.

    2015-07-01

    Nanosecond-scale evolution of plasma and RF electromagnetic fields during the release of energy from a microwave pulse compressor with a plasma interference switch was investigated numerically using the code MAGIC. The plasma was simulated in the scope of the gas conductivity model in MAGIC. The compressor embodied an S-band cavity and H-plane waveguide tee with a shorted side arm filled with pressurized gas. In a simplified approach, the gas discharge was initiated by setting an external ionization rate in a layer crossing the side arm waveguide in the location of the electric field antinode. It was found that with increasing ionization rate, the microwave energy absorbed by the plasma in the first few nanoseconds increases, but the absorption for the whole duration of energy release, on the contrary, decreases. In a hybrid approach modeling laser ignition of the discharge, seed electrons were set around the electric field antinode. In this case, the plasma extends along the field forming a filament and the plasma density increases up to the level at which the electric field within the plasma decreases due to the skin effect. Then, the avalanche rate decreases but the density still rises until the microwave energy release begins and the electric field becomes insufficient to support the avalanche process. The extraction of the microwave pulse limits its own power by terminating the rise of the plasma density and filament length. For efficient extraction, a sufficiently long filament of dense plasma must have sufficient time to be formed.

  2. [Influence of electromagnetic field on chosen parameters of thrombocytes' oxygen metabolism--in vitro research].

    Science.gov (United States)

    Jankowski, Wojciech; Henrykowska, Gabriela; Smigielski, Janusz; Pacholski, Krzysztof; Dziedziczak-Buczyńska, Maria; Kałka, Krzysztof; Buczyński, Andrzej

    2008-06-01

    Being a natural environmental factor, an electromagnetic field exists from the beginning of the life on Earth and it has an influence on maintenance of life processes. Natural electromagnetic fields affect day and year rhythms of plants, animals and humans. As a result of an electromagnetic field's activity, there occurs a disorder of blood platelets' function, which may, in consequence, lead to acute and chronic conditions dangerous to health and life. The aim of this work was to assess the influence, which a shape of an electromagnetic field of low frequency has on generating free radicals and enzymatic activity of superoxide dismutase in human blood platelets. Suspension of human blood platelets was subjected to activity of electromagnetic field of different shapes, frequency of 50 Hz and induction of 10 mT for 15 and 30 minutes. An electromagnetic field was generated with Helmholtz coils arranged on a bracket, inside of which test tubes with the blood platelets' suspension were put. Next, they were subjected to an activity of a specific electromagnetic field. The measurement of free radicals generation indicated an increase, in comparison with the initial values, after 15 minutes as well as 30 minutes of exposition, regardless of the electromagnetic field's shape, whereas the enzymatic activity of superoxide dismutase decreased, in comparison with the initial values, after 15 minutes as well as 30 minutes of exposition, regardless of the applied electromagnetic field's shape. Basing on obtained results, it may be stated that the level of generating free radicals as well as the level of enzymatic activity of superoxide dismutase in tested blood cells indicates significant dependence on an electromagnetic field's shape. The greatest changes have been observed during the activity of a rectangular and triangular pulse.

  3. Solution of the Bethe-Salpeter equation in the field of a plane electromagnetic wave

    International Nuclear Information System (INIS)

    Starostin, V.S.

    1988-01-01

    A solution is obtained of the Bethe--Salpeter equation for positronium in the field of linearly and circularly polarized plane electromagnetic waves at frequencies much higher than atomic. It is not assumed that the field is weak

  4. Device for converting electromagnetic radiation energy into electrical energy and method of manufacturing such a device

    NARCIS (Netherlands)

    2007-01-01

    Device (10) for converting electromagnetic radiation energy into electrical energy, comprising at least a photovoltaic element (11) with a radiation-sensitive surface, wherein a covering layer (12) of a material comprising a silicon compound, to which a rare earth element has been added, is present

  5. Anisotropic inflation with a non-minimally coupled electromagnetic field to gravity

    Science.gov (United States)

    Adak, Muzaffer; Akarsu, Özgür; Dereli, Tekin; Sert, Özcan

    2017-11-01

    We consider the non-minimal model of gravity in Y(R) F2-form. We investigate a particular case of the model, for which the higher order derivatives are eliminated but the scalar curvature R is kept to be dynamical via the constraint YRFmnFmn =-2/κ2. The effective fluid obtained can be represented by interacting electromagnetic field and vacuum depending on Y(R), namely, the energy density of the vacuum tracks R while energy density of the conventional electromagnetic field is dynamically scaled with the factor Y(R)/2. We give exact solutions for anisotropic inflation by assuming the volume scale factor of the Universe exhibits a power-law expansion. The directional scale factors do not necessarily exhibit power-law expansion, which would give rise to a constant expansion anisotropy, but expand non-trivially and give rise to a non-monotonically evolving expansion anisotropy that eventually converges to a non-zero constant. Relying on this fact, we discuss the anisotropic e-fold during the inflation by considering observed scale invariance in CMB and demanding the Universe to undergo the same amount of e-folds in all directions. We calculate the residual expansion anisotropy at the end of inflation, though as a result of non-monotonic behaviour of expansion anisotropy all the axes of the Universe undergo the same of amount of e-folds by the end of inflation. We also discuss the generation of the modified electromagnetic field during the first few e-folds of the inflation and its persistence against to the vacuum till end of inflation.

  6. Non-ionizing electromagnetic fields on offshore installations

    International Nuclear Information System (INIS)

    Stark, G.M.; Heaton, B.

    1996-01-01

    The concern over the effects of occupational exposure to non-ionizing electromagnetic fields (EMF) has greatly increased in recent years. A great deal of knowledge is known about the thermal effects of radiofrequency EMF's and at the moment, many epidemiological and laboratory studies are being performed on extremely low frequency (ELF) and very low frequency (VLF) EMF's. Some studies have reported an increased risk of leukaemia and other cancers in children living close to overhead power cables and power industry electrical workers. Wertheimer and Leeper reported cancer links in children residing near overhead power cables as early as 1979 and many subsequent studies have continued to make similar associations. These studies suggest that prolonged exposure to higher than normal magnetic fields increases the occurrence of certain cancers in both children and adults. The most common associations are between EMF's and leukaemia, other haematopoetic cancers, brain cancers, central nervous system cancers or melanomas. Studies of adults living near overhead lines by Youngson et al. and working in the electricity industry by Armstrong et al. and Savitz and Loomis have also shown associations with certain cancers. The epidemiological studies are incomplete in several areas and many have been openly criticized. As yet, there is no conclusive laboratory evidence but studies are ongoing. The Hendee and Boteler study suggested that 'EMF's might be cancer promoters but are unlikely to be cancer initiators'. In addition to ELF studies, there have been many reports investigating exposure to EMF's from visual display units with equivocal results. Laboratory studies have reported conflicting results and as yet the hazard, if any, is still uncertain. Reports have also recorded exposure levels of operators in broadcast radio stations showing a variety of levels dependent on the occupation. In December 1992, the Commission of the European Communities proposed a council Directive on

  7. Quaternion analysis of generalized electromagnetic fields in chiral media

    International Nuclear Information System (INIS)

    Bisht, P. S. . Email. ps_bisht123@rediffmail.com

    2007-01-01

    The time dependent Maxwell's equations in presence of electric and magnetic charges has been developed in chiral media and the solutions for the classical problem are obtained in unique, simple and consistent manner. The quaternionic reformulation of generalized electromagnetic fields in chiral media has also been developed in compact and consistent way. Simulation of neutron backscattering process applied to organic material detection. Forero Martinez, Nancy Carolina; Cristancho, Fernando (Nuclear Physics Group, Universidad Nacional de Colombia, Bogota D.C. (Colombia)) Abstract Atomic and nuclear physics based sensors might offer new possibilities in de-mining. There is a particular interest in the possibility of using neutrons for the non-intrusive detection of hidden contraband, explosives or illicit drugs. The Neutron Backscattering Technique, based on the detection of the produced thermal neutrons, is known to be a useful tool to detect hidden explosives which present an elevated concentration of light elements (H, C, N, O). In this way we present the simulated results using the program package Geant4. Different variables were modified including the soil composition and the studied materials. (Author)

  8. Neurovegetative disturbances in workers exposed to 50 Hz electromagnetic fields

    International Nuclear Information System (INIS)

    Bortkiewicz, A.; Gadzicka, E.; Zmyslony, M.; Szymczak, W.

    2006-01-01

    Since the circulatory and nervous systems are composed of of electrically excitable tissues, it is plausible that they can be stimulated by electromagnetic fields (EMF). No clinical studies have as been carried out to explain whether and how occupational exposure to 50 Hz EMF can influence the neurovegetative regulation of the cardiovascular function. The present project was undertaken to assess the the autonomic function in workers occupationally exposed to 50 Hz EMF, by analyzing the heart rate variability. The study group comprised 63 workers of switchyard substations, aged 22-67 years (39.2±10.0 years), and the control group 42 workers of radio link stations, aged 20-68 years (40.7±9.2 years), employed at workposts free from EMF exposure. The age range and employment duration in both groups did not differ significantly. To assess the neurovegetative regulation of the cardiac function, heart rate variability HRV) analysis was made based on 512 normal heart beats recorded at rest. The analysis, performed using fast Fourier transformation, concerned the time - and frequency-domain HRV parameters. Power spectrum in the very low (VLF), low (LF) and high (HF) frequency bands was determined. The relative risk of decreased HRV (STD R-R ) was significantly higher in the study group than in control (65% vs. 47%). It was concluded that occupational exposure to 50 Hz EMF could influence the neurovegetative regulation of the cardiovascular system. (author)

  9. Study of extremely low frequency electromagnetic fields in infant incubators.

    Science.gov (United States)

    Cermáková, Eleonora

    2003-01-01

    The aim of the work was to present the results of measurements of extremely low frequency electromagnetic fields (ELF EMF), namely the magnetic flux density, inside infant incubators, and to compare these results with the data published by other authors who point out to a possible association between leukemia or other diseases observed in newborns kept in incubators after the birth and the ELF EMF exposure in the incubator. The measured magnetic flux densities were compared with the reference values for this frequency range indicated in the European Union (EU) recommendations. The repeated measurements in incubators were made with a calibrated magnetometer EFA 300 in the frequency range of 5-30 kHz. Effective values of magnetic flux densities of ELF EMF were determined taking account of the reference values. The results of many repeated measurements showing the values of magnetic flux density in modern incubators with plastic supporting frame, were compared with those obtained in old type incubators with iron skeleton. A power frequency of 50 Hz was detected in the incubator and the ELF EMF values were by over two orders lower than the EU reference values. The paper emphasizes the need to take a special care of newborns kept in incubators even if only the sub-reference values are detected. The EU reference values are intended for the adult human population. A baby in an incubator has much smaller dimensions, higher electric conductivity and maybe trigger another mechanism of response to ELF EMF than that indicated in this paper.

  10. Effect of electromagnetic field on Kordylewski clouds formation

    Science.gov (United States)

    Salnikova, Tatiana; Stepanov, Sergey

    2018-05-01

    In previous papers the authors suggest a clarification of the phenomenon of appearance-disappearance of Kordylewski clouds - accumulation of cosmic dust mass in the vicinity of the triangle libration points of the Earth-Moon system. Under gravi-tational and light perturbation of the Sun the triangle libration points aren't the points of relative equilibrium. However, there exist the stable periodic motion of the particles, surrounding every of the triangle libration points. Due to this fact we can consider a probabilistic model of the dust clouds formation. These clouds move along the periodical orbits in small vicinity of the point of periodical orbit. To continue this research we suggest a mathematical model to investigate also the electromagnetic influences, arising under consideration of the charged dust particles in the vicinity of the triangle libration points of the Earth-Moon system. In this model we take under consideration the self-unduced force field within the set of charged particles, the probability distribution density evolves according to the Vlasov equation.

  11. Classical particles with spin in electromagnetic and gravitational fields

    International Nuclear Information System (INIS)

    Amorim, R.M. de.

    1977-02-01

    Following a review of several problems connected with classical particles with intrinsic angular momentum are reproduced the Frenkel equations (with the condition S sup(μν)U sub(ν)=0) by means of a holonomic variational principle, and have related them to Bargann, Michel and Tededgie equations. The treatment is then generalized to the case in wich S sup(μν)U sub(ν)=0 and the resulting equation coincide in the linearized limit with those obtained by Suttorp and de Groot. Also, by using variational principles, the generalizations to Frenkel equations are obtained, as well as to those of Suttorp and de Groot when electromagnetic and gravitational interactions are considered. Finally, those equations are analysed according to a scheme proposed by Oliveira and Tiommo where the gravitational interactions are described by gravielectric and gravimagnetic fields. The analogies in these equations of motion between the gravitational and eletromagnetic interactions, in the case in which the particle has a giromagnetic factor g=1, are shown. The last results complete a previous study by wald. (Author) [pt

  12. Oblique propagating electromagnetic ion - Cyclotron instability with A.C. field in outer magnetosphere

    Science.gov (United States)

    Pandey, R. S.; Singh, Vikrant; Rani, Anju; Varughese, George; Singh, K. M.

    2018-05-01

    In the present paper Oblique propagating electromagnetic ion-cyclotron wave has been analyzed for anisotropic multi ion plasma (H+, He+, O+ ions) in earth magnetosphere for the Dione shell of L=7 i.e., the outer radiation belt of the magnetosphere for Loss-cone distribution function with a spectral index j in the presence of A.C. electric field. Detail for particle trajectories and dispersion relation has been derived by using the method of characteristic solution on the basis of wave particle interaction and transformation of energy. Results for the growth rate have been calculated numerically for various parameters and have been compared for different ions present in magnetosphere. It has been found that for studying the wave over wider spectrum, anisotropy for different values of j should be taken. The effect of frequency of A.C. electric field and angle which propagation vector make with magnetic field, on growth rate has been explained.

  13. Calculation of transformers leakage reactance using electromagnetic energy technique

    International Nuclear Information System (INIS)

    Feiz, J.; Mohseni, H.; Sabet Marzooghi, S.; Naderian Jahromi, A.

    2004-01-01

    Determination of transformer leakage reactance using magnetic cores has long been an area of interest to engineers involved in the design of power and distribution transformers. This is required for predicting the performance of transformers before actual assembly of the transformers. In this paper a closed form solution technique applicable to the leakage reactance calculations for transformers is presented. An emphasis is on the development of a simple method to calculate the leakage reactance of the distribution transformers and smaller transformers. Energy technique procedure for computing the leakage reactances in distribution transformers is presented. This method is very efficient compared with the use of flux element and image technique and is also remarkably accurate. Examples of calculated leakage inductances and the short circuit impedance are given for illustration. For validation, the results are compared with the results obtained using test. This paper presents a novel technique for calculation of the leakage inductance in different parts of the transformer using the electromagnetic stored energy

  14. Beamed-Energy Propulsion (BEP): Considerations for Beaming High Energy-Density Electromagnetic Waves Through the Atmosphere

    Science.gov (United States)

    Manning, Robert M.

    2015-01-01

    A study to determine the feasibility of employing beamed electromagnetic energy for vehicle propulsion within and outside the Earth's atmosphere was co-funded by NASA and the Defense Advanced Research Projects Agency that began in June 2010 and culminated in a Summary Presentation in April 2011. A detailed report entitled "Beamed-Energy Propulsion (BEP) Study" appeared in February 2012 as NASA/TM-2012-217014. Of the very many nuances of this subject that were addressed in this report, the effects of transferring the required high energy-density electromagnetic fields through the atmosphere were discussed. However, due to the limitations of the length of the report, only a summary of the results of the detailed analyses were able to be included. It is the intent of the present work to make available the complete analytical modeling work that was done for the BEP project with regard to electromagnetic wave propagation issues. In particular, the present technical memorandum contains two documents that were prepared in 2011. The first one, entitled "Effects of Beaming Energy Through the Atmosphere" contains an overview of the analysis of the nonlinear problem inherent with the transfer of large amounts of energy through the atmosphere that gives rise to thermally-induced changes in the refractive index; application is then made to specific beamed propulsion scenarios. A brief portion of this report appeared as Appendix G of the 2012 Technical Memorandum. The second report, entitled "An Analytical Assessment of the Thermal Blooming Effects on the Propagation of Optical and Millimeter- Wave Focused Beam Waves For Power Beaming Applications" was written in October 2010 (not previously published), provides a more detailed treatment of the propagation problem and its effect on the overall characteristics of the beam such as its deflection as well as its radius. Comparisons are then made for power beaming using the disparate electromagnetic wavelengths of 1.06 microns and 2

  15. Energy Resolution of the Barrel of the CMS Electromagnetic Calorimeter

    CERN Document Server

    Adzic, Petar; Almeida, Carlos; Almeida, Nuno; Anagnostou, Georgios; Anfreville, Marc; Anicin, Ivan; Antunovic, Zeljko; Auffray, Etiennette; Baccaro, Stefania; Baffioni, Stephanie; Baillon, Paul; Barney, David; Barone, Luciano; Barrillon, Pierre; Bartoloni, Alessandro; Beauceron, Stephanie; Beaudette, Florian; Bell, Ken W; Benetta, Robert; Bercher, Michel; Berthon, Ursula; Betev, Botjo; Beuselinck, Raymond; Bhardwaj, Ashutosh; Bialas, Wojciech; Biino, Cristina; Bimbot, Stephane; Blaha, Jan; Bloch, Philippe; Blyth, Simon; Bordalo, Paula; Bornheim, Adolf; Bourotte, Jean; Britton, David; Brown, Robert M; Brunelière, Renaud; Busson, Philippe; Camporesi, Tiziano; Cartiglia, Nicolo; Cavallari, Francesca; Cerutti, Muriel; Chamont, David; Chang, Paoti; Chang, You-Hao; Charlot, Claude; Chatterji, Sudeep; Chen, E Augustine; Chipaux, Rémi; Choudhary, Brajesh C; Cockerill, David J A; Collard, Caroline; Combaret, Christophe; Cossutti, Fabio; Da Silva, J C; Dafinei, Ioan; Daskalakis, Georgios; Davatz, Giovanna; Decotigny, David; De Min, Alberto; Deiters, Konrad; Dejardin, Marc; Del Re, Daniele; Della Negra, Rodolphe; Della Ricca, Giuseppe; Depasse, Pierre; Descamp, J; Dewhirst, Guy; Dhawan, Satish; Diemoz, Marcella; Dissertori, Günther; Dittmar, Michael; Djambazov, Lubomir; Dobrzynski, Ludwik; Drndarevic, Snezana; Dupanloup, Michel; Dzelalija, Mile; Ehlers, Jan; El-Mamouni, H; Peisert, Anna; Evangelou, Ioannis; Fabbro, Bernard; Faure, Jean-Louis; Fay, Jean; Ferri, Federico; Flower, Paul S; Franzoni, Giovanni; Funk, Wolfgang; Gaillac, Anne-Marie; Gargiulo, Corrado; Gascon-Shotkin, S; Geerebaert, Yannick; Gentit, François-Xavier; Ghezzi, Alessio; Gilly, Jean; Giolo-Nicollerat, Anne-Sylvie; Givernaud, Alain; Gninenko, Sergei; Go, Apollo; Godinovic, Nikola; Golubev, Nikolai; Golutvin, Igor; Gómez-Reino, Robert; Govoni, Pietro; Grahl, James; Gras, Philippe; Greenhalgh, Justin; Guillaud, Jean-Paul; Haguenauer, Maurice; Hamel De Montechenault, G; Hansen, Magnus; Heath, Helen F; Hill, Jack; Hobson, Peter R; Holmes, Daniel; Holzner, André; Hou, George Wei-Shu; Ille, Bernard; Ingram, Quentin; Jain, Adarsh; Jarry, Patrick; Jauffret, C; Jha, Manoj; Karar, M A; Kataria, Sushil Kumar; Katchanov, V A; Kennedy, Bruce W; Kloukinas, Kostas; Kokkas, Panagiotis; Korjik, M; Krasnikov, Nikolai; Krpic, Dragomir; Kyriakis, Aristotelis; Lebeau, Michel; Lecomte, Pierre; Lecoq, Paul; Lemaire, Marie-Claude; Lethuillier, Morgan; Lin, Willis; Lintern, A L; Lister, Alison; Litvin, V; Locci, Elizabeth; Lodge, Anthony B; Longo, Egidio; Loukas, Demetrios; Luckey, D; Lustermann, Werner; Lynch, Clare; MacKay, Catherine Kirsty; Malberti, Martina; Maletic, Dimitrije; Mandjavidze, Irakli; Manthos, Nikolaos; Markou, Athanasios; Mathez, Hervé; Mathieu, Antoine; Matveev, Viktor; Maurelli, Georges; Menichetti, Ezio; Meridiani, Paolo; Milenovic, Predrag; Milleret, Gérard; Miné, Philippe; Mur, Michel; Musienko, Yuri; Nardulli, Alessandro; Nash, Jordan; Neal, Homer; Nédélec, Patrick; Negri, Pietro; Nessi-Tedaldi, Francesca; Newman, Harvey B; Nikitenko, Alexander; Obertino, Maria Margherita; Ofierzynski, Radoslaw Adrian; Organtini, Giovanni; Paganini, Pascal; Paganoni, Marco; Papadopoulos, Ioannis; Paramatti, Riccardo; Pastrone, Nadia; Pauss, Felicitas; Puljak, Ivica; Pullia, Antonino; Puzovic, Jovan; Ragazzi, Stefano; Ramos, Sergio; Rahatlou, Shahram; Rander, John; Ranjan, Kirti; Ravat, Olivier; Raymond, M; Razis, Panos A; Redaelli, Nicola; Renker, Dieter; Reucroft, Steve; Reymond, Jean-Marc; Reynaud, Michel; Reynaud, Serge; Romanteau, Thierry; Rondeaux, Françoise; Rosowsky, André; Rovelli, Chiara; Rumerio, Paolo; Rusack, Roger; Rusakov, Sergey V; Ryan, Matthew John; Rykaczewski, Hans; Sakhelashvili, Tariel; Salerno, Roberto; Santos, Marcelino; Seez, Christopher; Semeniouk, Igor; Sharif, Omar; Sharp, Peter; Shepherd-Themistocleous, Claire; Shevchenko, Sergey; Shivpuri, Ram Krishen; Sidiropoulos, Georgios; Sillou, Daniel; Singovsky, Alexander; Sirois, Y; Sirunyan, Albert M; Smith, Brian; Smith, Vincent J; Sproston, Martin; Suter, Henry; Swain, John; Tabarelli de Fatis, Tommaso; Takahashi, Maiko; Tapper, Robert J; Tcheremoukhine, Alexandre; Teixeira, Isabel; Teixeira, Joao Paulo; Teller, Olivier; Timlin, Claire; Triantis, F A; Troshin, Sergey; Tyurin, Nikolay; Ueno, Koji; Uzunian, Andrey; Varela, Joao; Vaz-Cardoso, N; Verrecchia, Patrice; Vichoudis, Paschalis; Vigano, S; Viertel, Gert; Virdee, Tejinder; Vlassov, E; Wang, Minzu; Weinstein, Alan; Williams, Jennifer C; Yaselli, Ignacio; Zabi, Alexandre; Zamiatin, Nikolai; Zelepoukine, Serguei; Zeller, Michael E; Zhang, Lin; Zhang, Jia-Wen; Zhang, Yawei; Zhu, Kejun; Zhu, Ren-Yuan

    2007-01-01

    The energy resolution of the barrel part of the CMS Electromagnetic Calorimeter has been studied using electrons of 20 to 250 GeV in a test beam. The incident electron's energy was reconstructed by summing the energy measured in arrays of 3x3 or 5x5 channels. There was no significant amount of correlated noise observed within these arrays. For electrons incident at the centre of the studied 3x3 arrays of crystals, the mean stochastic term was measured to be 2.8% and the mean constant term to be 0.3%. The amount of the incident electron's energy which is contained within the array depends on its position of incidence. The variation of the containment with position is corrected for using the distribution of the measured energy within the array. For uniform illumination of a crystal with 120 GeV electrons a resolution of 0.5% was achieved. The energy resolution meets the design goal for the detector.

  16. Parametric Analysis and Experimental Verification of a Hybrid Vibration Energy Harvester Combining Piezoelectric and Electromagnetic Mechanisms

    Directory of Open Access Journals (Sweden)

    Zhenlong Xu

    2017-06-01

    Full Text Available Considering coil inductance and the spatial distribution of the magnetic field, this paper developed an approximate distributed-parameter model of a hybrid energy harvester (HEH. The analytical solutions were compared with numerical solutions. The effects of load resistances, electromechanical coupling factors, mechanical damping ratio, coil parameters and size scale on performance were investigated. A meso-scale HEH prototype was fabricated, tested and compared with a stand-alone piezoelectric energy harvester (PEH and a stand-alone electromagnetic energy harvester (EMEH. The peak output power is 2.93% and 142.18% higher than that of the stand-alone PEH and EMEH, respectively. Moreover, its bandwidth is 108%- and 122.7%-times that of the stand-alone PEH and EMEH, respectively. The experimental results agreed well with the theoretical values. It is indicated that the linearized electromagnetic coupling coefficient is more suitable for low-level excitation acceleration. Hybrid energy harvesting contributes to widening the frequency bandwidth and improving energy conversion efficiency. However, only when the piezoelectric coupling effect is weak or medium can the HEH generate more power than the single-mechanism energy harvester. Hybrid energy harvesting can improve output power even at the microelectromechanical systems (MEMS scale. This study presents a more effective model for the performance evaluation and structure optimization of the HEH.

  17. Coupled poroelastic waves and electromagnetic fields in layered media : Theory, Modeling, and Interferometric Synthesis

    NARCIS (Netherlands)

    Grobbe, N.

    2016-01-01

    In this thesis, I study coupled poroelastic waves and electromagnetic fields in layered media. The focus is two-fold:
    1. Increase the theoretical and physical understanding of the seismo-electromagnetic phenomenon by analytically-based numerical modeling.
    2. Investigate the potential of

  18. Near-Field Spectral Effects due to Electromagnetic Surface Excitations

    OpenAIRE

    Shchegrov , Andrei ,; Joulain , Karl; Carminati , Rémi; Greffet , Jean-Jacques

    2000-01-01

    International audience; We demonstrate theoretically that the spectra of electromagnetic emission of surface systems can display remarkable differences in the near and the far zones. The spectral changes occur due to the loss of evanescent modes and are especially pronounced for systems which support surface waves. PACS numbers: 78.20. – e, 05.40. – a, 44.40. + a, 87.64.Xx Spectroscopy of electromagnetic radiation is perhaps the most powerful exploration tool employed in natural sciences: ast...

  19. Two-photon cooperative emission in the presence of athermal electromagnetic field

    International Nuclear Information System (INIS)

    Enaki, N.A.; Mihalache, D.

    1997-01-01

    The possibility of cooperative spontaneous two-photon emission of an extended radiators system and the influence of the external thermal electromagnetic field on the spontaneous emission rate, in such a system, are investigated. It is concluded that, in an external electromagnetic field, the two-photon cooperative emission rate increases significantly. The importance of this effect on the emission of gamma rays from inverted long-lived isomers triggered by X-ray thermal fields, is emphasized

  20. Microelectronic sensors for measurement of electromagnetic field of living cells and experimental results

    Czech Academy of Sciences Publication Activity Database

    Jelínek, František; Pokorný, Jiří; Šaroch, Jaroslav; Trkal, Viktor; Hašek, Jiří; Palán, B.

    1999-01-01

    Roč. 48, č. 2 (1999), s. 261-266 ISSN 0302-4598. [Electromagnetic Fields in Biological Systems. Prague, 13.09.1998-16.09.1998] R&D Projects: GA ČR GA102/97/0867 Grant - others:EU COST (XE) OC 244B.40 Institutional research plan: CEZ:AV0Z2067918 Keywords : electromagnetic fields * cellular biophysics * field strength measurement Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.085, year: 1999

  1. Polarization dynamics and polarization time of random three-dimensional electromagnetic fields

    International Nuclear Information System (INIS)

    Voipio, Timo; Setaelae, Tero; Shevchenko, Andriy; Friberg, Ari T.

    2010-01-01

    We investigate the polarization dynamics of random, stationary three-dimensional (3D) electromagnetic fields. For analyzing the time evolution of the instantaneous polarization state, two intensity-normalized polarization autocorrelation functions are introduced, one based on a geometric approach with the Poincare vectors and the other on energy considerations with the Jones vectors. Both approaches lead to the same conclusions on the rate and strength of the polarization dynamics and enable the definition of a polarization time over which the state of polarization remains essentially unchanged. For fields obeying Gaussian statistics, the two correlation functions are shown to be expressible in terms of quantities characterizing partial 3D polarization and electromagnetic coherence. The 3D degree of polarization is found to have the same meaning in the 3D polarization dynamics as the usual two-dimensional (2D) degree of polarization does with planar fields. The formalism is demonstrated with several examples, and it is expected to be useful in applications dealing with polarization fluctuations of 3D light.

  2. Ultrastructural Study on Ultra-Low Frequency Electromagnetic Fields and Transfer Factor Effects on Skin Ulcers

    International Nuclear Information System (INIS)

    Cadena, M. S. Reyes; Chapul, L. Sanchez; Perez, Javier; Garcia, M. N. Jimenez; Lopez, M. A. Jimenez; Espindola, M. E. Sanchez; Perez, R. Paniagua; Hernandez, N. A.; Paniagua, G.; Uribe, F.; Nava, J. J. Godina; Segura, M. A. Rodriguez

    2008-01-01

    We determined the effect of 120Hz ultra low frequency electromagnetic field (ELF) on the healing process of skin in 20 Wistar rats distributed in four groups in which chronic dermal ulcers had been produced. The first two groups received a dose of the transfer factor and interferon-beta (IFN-β) every 24 h during 12 days. The third group (positive control) received only electromagnetic field (ELF) sessions, and in the fourth group (negative control), no treatment was applied. The electromagnetic field was applied through a Helmholtz coils; 30 Gauss of intensity. Results shown histological changes that improve the healing process in animals subjected to ELF together with the transfer factor

  3. Pair creation of neutral particles in a vacuum by external electromagnetic fields in 2 + 1 dimensions

    International Nuclear Information System (INIS)

    Qiong-gui Lin; Department of Physics, Zhongshan University, Guangzhou 510275

    1999-01-01

    Neutral fermions of spin-1/2 with magnetic moment can interact with electromagnetic fields through nonminimal coupling. In 2 + 1 dimensions the electromagnetic field strength plays the same role to the magnetic moment as the vector potential to the electric charge. This duality enables one to obtain physical results for neutral particles from known ones for charged particles. We give the probability of neutral particle-antiparticle pair creation in a vacuum by non-uniform electromagnetic fields produced by constant uniform charge and current densities. (author)

  4. Resonator as high frequency electromagnetic field oscillation generator

    International Nuclear Information System (INIS)

    Svoroba, O.V.; Scherbina, V.O.

    2007-01-01

    The problem of finding the u(x-vector) field potential in a specific waveguide with generalized corrugated core geometry is considered. The perturbation is brought to the system by high energy electron beam, injected in a waveguide. It is shown that the Neumann spectral problem can be reduced to finding Green approximation solution, and how it can be solved by the discretization technique. Considered parameterization allow to optimize the u(x-vector) field for specific frequency tuning. This method can be used as plasma heating method for thermonuclear temperature control

  5. Effects of Electromagnetic Fields on Fish and Invertebrates: Task 2.1.3: Effects on Aquatic Organisms - Fiscal Year 2011 Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

    Energy Technology Data Exchange (ETDEWEB)

    Woodruff, Dana L.; Schultz, Irvin R.; Marshall, Kathryn E.; Ward, Jeffrey A.; Cullinan, Valerie I.

    2012-05-01

    This fiscal year (FY) 2011 progress report (Task 2.1.3 Effects on Aquatic Organisms, Subtask 2.3.1.1 Electromagnetic Fields) describes studies conducted by PNNL as part of the DOE Wind and Water Power Program to examine the potential effects of electromagnetic fields (EMF) from marine and hydrokinetic devices on aquatic organisms, including freshwater and marine fish and marine invertebrates. In this report, we provide a description of the methods and results of experiments conducted in FY 2010-FY 2011 to evaluate potential responses of selected aquatic organisms. Preliminary EMF laboratory experiments during FY 2010 and 2011 entailed exposures with representative fish and invertebrate species including juvenile coho salmon (Oncorhynchus kisutch), Atlantic halibut (Hippoglossus hippoglossus), California halibut (Paralicthys californicus), rainbow trout (Oncorhynchus mykiss), and Dungeness crab (Metacarcinus magister). These species were selected for their ecological, commercial, and/or recreational importance, as well as their potential to encounter an MHK device or transmission cable during part or all of their life cycle. Based on previous studies, acute effects such as mortality were not expected to occur from EMF exposures. Therefore, our measurement endpoints focused on behavioral responses (e.g., detection of EMF, interference with feeding behavior, avoidance or attraction to EMF), developmental changes (i.e., growth and survival from egg or larval stage to juvenile), and exposure markers indicative of physiological responses to stress. EMF intensities during the various tests ranged from 0.1 to 3 millitesla, representing a range of upper bounding conditions reported in the literature. Experiments to date have shown there is little evidence to indicate distinct or extreme behavioral responses in the presence of elevated EMF for the species tested. Several developmental and physiological responses were observed in the fish exposures, although most were not

  6. Radiofrequency-electromagnetic field exposures in kindergarten children.

    Science.gov (United States)

    Bhatt, Chhavi Raj; Redmayne, Mary; Billah, Baki; Abramson, Michael J; Benke, Geza

    2017-09-01

    The aim of this study was to assess environmental and personal radiofrequency-electromagnetic field (RF-EMF) exposures in kindergarten children. Ten children and 20 kindergartens in Melbourne, Australia participated in personal and environmental exposure measurements, respectively. Order statistics of RF-EMF exposures were computed for 16 frequency bands between 88 MHz and 5.8 GHz. Of the 16 bands, the three highest sources of environmental RF-EMF exposures were: Global System for Mobile Communications (GSM) 900 MHz downlink (82 mV/m); Universal Mobile Telecommunications System (UMTS) 2100MHz downlink (51 mV/m); and GSM 900 MHz uplink (45 mV/m). Similarly, the three highest personal exposure sources were: GSM 900 MHz downlink (50 mV/m); UMTS 2100 MHz downlink, GSM 900 MHz uplink and GSM 1800 MHz downlink (20 mV/m); and Frequency Modulation radio, Wi-Fi 2.4 GHz and Digital Video Broadcasting-Terrestrial (10 mV/m). The median environmental exposures were: 179 mV/m (total all bands), 123 mV/m (total mobile phone base station downlinks), 46 mV/m (total mobile phone base station uplinks), and 16 mV/m (Wi-Fi 2.4 GHz). Similarly, the median personal exposures were: 81 mV/m (total all bands), 62 mV/m (total mobile phone base station downlinks), 21 mV/m (total mobile phone base station uplinks), and 9 mV/m (Wi-Fi 2.4 GHz). The measurements showed that environmental RF-EMF exposure levels exceeded the personal RF-EMF exposure levels at kindergartens.

  7. Personal radiofrequency electromagnetic field exposure measurements in Swiss adolescents.

    Science.gov (United States)

    Roser, Katharina; Schoeni, Anna; Struchen, Benjamin; Zahner, Marco; Eeftens, Marloes; Fröhlich, Jürg; Röösli, Martin

    2017-02-01

    Adolescents belong to the heaviest users of wireless communication devices, but little is known about their personal exposure to radiofrequency electromagnetic fields (RF-EMF). The aim of this paper is to describe personal RF-EMF exposure of Swiss adolescents and evaluate exposure relevant factors. Furthermore, personal measurements were used to estimate average contributions of various sources to the total absorbed RF-EMF dose of the brain and the whole body. Personal exposure was measured using a portable RF-EMF measurement device (ExpoM-RF) measuring 13 frequency bands ranging from 470 to 3600MHz. The participants carried the device for three consecutive days and kept a time-activity diary. In total, 90 adolescents aged 13 to 17years participated in the study conducted between May 2013 and April 2014. In addition, personal measurement values were combined with dose calculations for the use of wireless communication devices to quantify the contribution of various RF-EMF sources to the daily RF-EMF dose of adolescents. Main contributors to the total personal RF-EMF measurements of 63.2μW/m 2 (0.15V/m) were exposures from mobile phones (67.2%) and from mobile phone base stations (19.8%). WLAN at school and at home had little impact on the personal measurements (WLAN accounted for 3.5% of total personal measurements). According to the dose calculations, exposure from environmental sources (broadcast transmitters, mobile phone base stations, cordless phone base stations, WLAN access points, and mobile phones in the surroundings) contributed on average 6.0% to the brain dose and 9.0% to the whole-body dose. RF-EMF exposure of adolescents is dominated by their own mobile phone use. Environmental sources such as mobile phone base stations play a minor role. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Interaction of an atom subject to an intense laser field with its own radiation field and nonlocality of electromagnetic interaction

    International Nuclear Information System (INIS)

    Gainutdinov, R Kh; Mutygullina, A A

    2009-01-01

    We discuss the interaction of an atom subject to an intense driving laser field with its own radiation field. In contrast to the states of bare atoms, the energy difference between some dressed states with the same total angular momentum, its projection and parity may be very small. The self-interaction of a combined atom-laser system associated with nonradiative transitions between such states is effectively strong. We show that the contribution to the radiative shift of the sidebands of the Mollow spectrum, which comes from such processes, is very significant and may be much larger than the trivial Lamb shift, which is the simple redistribution of the Lamb shifts of the corresponding bare states. In the final part, we discuss the possibility that in the Mollow spectrum nonlocality of electromagnetic interaction, which in other cases is hidden in the regularization and renormalization procedures, can manifest itself explicitly.

  9. Energy reconstruction and calibration algorithms for the ATLAS electromagnetic calorimeter

    CERN Document Server

    Delmastro, M

    2003-01-01

    The work of this thesis is devoted to the study, development and optimization of the algorithms of energy reconstruction and calibration for the electromagnetic calorimeter (EMC) of the ATLAS experiment, presently under installation and commissioning at the CERN Large Hadron Collider in Geneva (Switzerland). A deep study of the electrical characteristics of the detector and of the signals formation and propagation is conduced: an electrical model of the detector is developed and analyzed through simulations; a hardware model (mock-up) of a group of the EMC readout cells has been built, allowing the direct collection and properties study of the signals emerging from the EMC cells. We analyze the existing multiple-sampled signal reconstruction strategy, showing the need of an improvement in order to reach the advertised performances of the detector. The optimal filtering reconstruction technique is studied and implemented, taking into account the differences between the ionization and calibration waveforms as e...

  10. Electromagnetism

    CERN Document Server

    Grant, Ian S

    1990-01-01

    The Manchester Physics Series General Editors: D. J. Sandiford; F. Mandl; A. C. Phillips Department of Physics and Astronomy, University of Manchester Properties of Matter B. H. Flowers and E. Mendoza Optics Second Edition F. G. Smith and J. H. Thomson Statistical Physics Second Edition F. Mandl Electromagnetism Second Edition I. S. Grant and W. R. Phillips Statistics R. J. Barlow Solid State Physics Second Edition J. R. Hook and H. E. Hall Quantum Mechanics F. Mandl Particle Physics Second Edition B. R. Martin and G. Shaw the Physics of Stars Second Edition A. C. Phillips Computing for Scient

  11. Engineering Electromagnetics

    International Nuclear Information System (INIS)

    Kim, Se Yun

    2009-01-01

    This book deals with engineering electromagnetics. It contains seven chapters, which treats understanding of engineering electromagnetics such as magnet and electron spin, current and a magnetic field and an electromagnetic wave, Essential tool for engineering electromagnetics on rector and scalar, rectangular coordinate system and curl vector, electrostatic field with coulomb rule and method of electric images, Biot-Savart law, Ampere law and magnetic force, Maxwell equation and an electromagnetic wave and reflection and penetration of electromagnetic plane wave.

  12. Quantum transition and decoherence of levitating polaron on helium film thickness under an electromagnetic field

    Science.gov (United States)

    Kenfack, S. C.; Fotue, A. J.; Fobasso, M. F. C.; Djomou, J.-R. D.; Tiotsop, M.; Ngouana, K. S. L.; Fai, L. C.

    2017-12-01

    We have studied the transition probability and decoherence time of levitating polaron in helium film thickness. By using a variational method of Pekar type, the ground and the first excited states of polaron are calculated above the liquid-helium film placed on the polar substrate. It is shown that the polaron transits from the ground to the excited state in the presence of an external electromagnetic field in the plane. We have seen that, in the helium film, the effects of the magnetic and electric fields on the polaron are opposite. It is also shown that the energy, transition probability and decoherence time of the polaron depend sensitively on the helium film thickness. We found that decoherence time decreases as a function of increasing electron-phonon coupling strength and the helium film thickness. It is seen that the film thickness can be considered as a new confinement in our system and can be adjusted in order to reduce decoherence.

  13. Projective multifragments break-up and the electromagnetic field effect of target nucleus

    International Nuclear Information System (INIS)

    Nabil Yasin, M.

    1994-12-01

    This work presents a special type of interactions produced in emulsion targets exposed to different incident beams of light ions at a few GeV per nucleon. The events characterised by multifragment break-up of the projectile nucleus which are produced via peripheral collisions or due to the effect of the Coulomb field of the target nucleus have been selected. The size of impact parameter must be considered for determining the type of the interaction. The results are compared with other collected data at energies (up to 200 GeV/nucleon). The dependence of electromagnetic dissociation cross section on the incident projectile energy is investigated. Also, a comparison of the experimental data with the assumed virtual photon spectrum using Weizsaecker-Williams (WW) method is made. (author). 34 refs, 3 figs, 4 tabs

  14. The Electromagnetic Zero-Point Field and the Flat Polarizable Vacuum Representation

    CERN Document Server

    Desiato, J T

    2003-01-01

    There are several interpretations of the Polarizable Vacuum (PV). One is the variable speed of light (VSL) approach, that has been shown to be isomorphic to General Relativity (GR) within experimental limits. However, another interpretation is representative of flat geometry, in which intervals of time and distance are measured in local inertial reference frames where the speed of light remains constant. The Flat PV approach leads to variable impedance transformations, governed by the spectral energy content of the Quantum Vacuum’s Electromagnetic (EM) Zero-Point Field (ZPF). The EM ZPF consists of photons. An unlimited number of photons may occupy the same quantum state at an arbitrary set of coordinates. Therefore, the spectral energy of the ZPF may be varied smoothly, represented by a superposition of EM waves with a large number of photons per cubic wavelength. Utilizing the Flat PV representation, a family of frequency dependent solutions of Poisson’s equation are derived, that may be applied as tool...

  15. Evaluation of specific absorption rate as a dosimetric quantity for electromagnetic fields bioeffects.

    Directory of Open Access Journals (Sweden)

    Dimitris J Panagopoulos

    Full Text Available PURPOSE: To evaluate SAR as a dosimetric quantity for EMF bioeffects, and identify ways for increasing the precision in EMF dosimetry and bioactivity assessment. METHODS: We discuss the interaction of man-made electromagnetic waves with biological matter and calculate the energy transferred to a single free ion within a cell. We analyze the physics and biology of SAR and evaluate the methods of its estimation. We discuss the experimentally observed non-linearity between electromagnetic exposure and biological effect. RESULTS: WE FIND THAT: a The energy absorbed by living matter during exposure to environmentally accounted EMFs is normally well below the thermal level. b All existing methods for SAR estimation, especially those based upon tissue conductivity and internal electric field, have serious deficiencies. c The only method to estimate SAR without large error is by measuring temperature increases within biological tissue, which normally are negligible for environmental EMF intensities, and thus cannot be measured. CONCLUSIONS: SAR actually refers to thermal effects, while the vast majority of the recorded biological effects from man-made non-ionizing environmental radiation are non-thermal. Even if SAR could be accurately estimated for a whole tissue, organ, or body, the biological/health effect is determined by tiny amounts of energy/power absorbed by specific biomolecules, which cannot be calculated. Moreover, it depends upon field parameters not taken into account in SAR calculation. Thus, SAR should not be used as the primary dosimetric quantity, but used only as a complementary measure, always reporting the estimating method and the corresponding error. Radiation/field intensity along with additional physical parameters (such as frequency, modulation etc which can be directly and in any case more accurately measured on the surface of biological tissues, should constitute the primary measure for EMF exposures, in spite of similar

  16. Evaluation of specific absorption rate as a dosimetric quantity for electromagnetic fields bioeffects.

    Science.gov (United States)

    Panagopoulos, Dimitris J; Johansson, Olle; Carlo, George L

    2013-01-01

    To evaluate SAR as a dosimetric quantity for EMF bioeffects, and identify ways for increasing the precision in EMF dosimetry and bioactivity assessment. We discuss the interaction of man-made electromagnetic waves with biological matter and calculate the energy transferred to a single free ion within a cell. We analyze the physics and biology of SAR and evaluate the methods of its estimation. We discuss the experimentally observed non-linearity between electromagnetic exposure and biological effect. WE FIND THAT: a) The energy absorbed by living matter during exposure to environmentally accounted EMFs is normally well below the thermal level. b) All existing methods for SAR estimation, especially those based upon tissue conductivity and internal electric field, have serious deficiencies. c) The only method to estimate SAR without large error is by measuring temperature increases within biological tissue, which normally are negligible for environmental EMF intensities, and thus cannot be measured. SAR actually refers to thermal effects, while the vast majority of the recorded biological effects from man-made non-ionizing environmental radiation are non-thermal. Even if SAR could be accurately estimated for a whole tissue, organ, or body, the biological/health effect is determined by tiny amounts of energy/power absorbed by specific biomolecules, which cannot be calculated. Moreover, it depends upon field parameters not taken into account in SAR calculation. Thus, SAR should not be used as the primary dosimetric quantity, but used only as a complementary measure, always reporting the estimating method and the corresponding error. Radiation/field intensity along with additional physical parameters (such as frequency, modulation etc) which can be directly and in any case more accurately measured on the surface of biological tissues, should constitute the primary measure for EMF exposures, in spite of similar uncertainty to predict the biological effect due to non-linearity.

  17. Interaction of electromagnetic energy with biological material - relation to food processing

    NARCIS (Netherlands)

    Ponne, C.T.; Bartels, P.V.

    1995-01-01

    For food scientists and technologists, the interaction of electromagnetic energy with enzymes, microorganisms and other food compounds is important in optimizing process efficiency and/or product quality. To be able to implement research findings on interaction of electromagnetic energy with matter;

  18. Electromagnetic response in kinetic energy driven cuprate superconductors: Linear response approach

    International Nuclear Information System (INIS)

    Krzyzosiak, Mateusz; Huang, Zheyu; Feng, Shiping; Gonczarek, Ryszard

    2010-01-01

    Within the framework of the kinetic energy driven superconductivity, the electromagnetic response in cuprate superconductors is studied in the linear response approach. The kernel of the response function is evaluated and employed to calculate the local magnetic field profile, the magnetic field penetration depth, and the superfluid density, based on the specular reflection model for a purely transverse vector potential. It is shown that the low temperature magnetic field profile follows an exponential decay at the surface, while the magnetic field penetration depth depends linearly on temperature, except for the strong deviation from the linear characteristics at extremely low temperatures. The superfluid density is found to decrease linearly with decreasing doping concentration in the underdoped regime. The problem of gauge invariance is addressed and an approximation for the dressed current vertex, which does not violate local charge conservation is proposed and discussed.

  19. Electromagnetic energy density and stress tensor in a warm plasma with finite flow velocity

    International Nuclear Information System (INIS)

    Choi, Cheong R.; Lee, Nam C.

    2004-01-01

    The expressions of the average of energy density and the average stress tensor of the electromagnetic field in a warm collisionless plasma moving with a finite velocity are obtained by using a microscopic method that uses the fluid description of plasma. The result contains terms involved with derivatives of the dielectric tensor with respect to the velocity, which explicitly represent the effects of the finite velocity of the medium. In the zero-velocity limit, the results reduce to the well-known expressions for a plasma at rest with temporal and spatial dispersion

  20. Towards the petascale in electromagnetic modeling of plasma-based accelerators for high-energy physics

    International Nuclear Information System (INIS)

    Bruhwiler, D L; Antonsen, T; Cary, J R; Cooley, J; Decyk, V K; Esarey, E; Geddes, C G R; Huang, C; Hakim, A; Katsouleas, T; Messmer, P; Mori, W B; Tsung, F S; Vieira, J; Zhou, M

    2006-01-01

    Plasma-based lepton acceleration concepts are a key element of the long-term R and D portfolio for the U.S. Office of High Energy Physics. There are many such concepts, but we consider only the laser (LWFA) and plasma (PWFA) wakefield accelerators. We present a summary of electromagnetic particle-in-cell (PIC) simulations for recent LWFA and PWFA experiments. These simulations, including both time explicit algorithms and reduced models, have effectively used terascale computing resources to support and guide experiments in this rapidly developing field. We briefly discuss the challenges and opportunities posed by the near-term availability of petascale computing hardware

  1. Effects of 1.84 GHz radio-frequency electromagnetic field on sperm ...

    African Journals Online (AJOL)

    sunny t

    found that, compared with sham group, the sperm morphology and ... harmful effects of electromagnetic fields emitted from ... RF-EMF, which are widely selected for mobile ... Laboratory Animal Centre, the Fourth Military Medical University,.

  2. Use of Pulsing Electromagnetic Fields for the Treatment of Pelvic Stress Fractures Among Female Soldiers

    National Research Council Canada - National Science Library

    Jones, D

    1995-01-01

    .... Pulsing electromagnetic fields (PEMFs)have been shown to speed the healing of non-union fractures and we have used them successfully to treat stress fractures in the lower limbs. All women at Ft...

  3. Peculiarities of natural electromagnetic field variations in the interval of periods of 60-240 min

    International Nuclear Information System (INIS)

    Kovtun, A.A.; Smirnov, M.Yu.

    1996-01-01

    Intensification of the oscillation amplitude of the natural electromagnetic field within 60-240 min period interval at practically all the latitudes was observed during the Earth re-entry to plasma high-speed flow

  4. Effect of electromagnetic fields on the chondrogenic differentiation under microgravity conditions

    Data.gov (United States)

    National Aeronautics and Space Administration — A combination therapy of electromagnetic fields (EMF) and simulated microgravity (SMG) has not been examined in regenerative medicine of cartilage. In the present...

  5. Effect of radio frequency waves of electromagnetic field on the tubulin.

    Science.gov (United States)

    Taghi, Mousavi; Gholamhosein, Riazi; Saeed, Rezayi-Zarchi

    2013-09-01

    Microtubules (MTs) are macromolecular structures consisting of tubulin heterodimers and present in almost every eukaryotic cell. MTs fulfill all conditions for generation of electromagnetic field and are electrically polar due to the electrical polarity of a tubulin heterodimer. The calculated static electric dipole moment of about 1000 Debye makes them capable of being aligned parallel to the applied electromagnetic field direction. In the present study, the tubulin heterodimers were extracted and purified from the rat brains. MTs were obtained by polymerization in vitro. Samples of microtubules were adsorbed in the absence and in the presence of electromagnetic fields with radio frequency of 900 Hz. Our results demonstrate the effect of electromagnetic field with 900 Hz frequency to change the structure of MTs. In this paper, a related patent was used that will help to better understand the studied subject.

  6. New analytical results in the electromagnetic response of composite superconducting wire in parallel fields

    NARCIS (Netherlands)

    Niessen, E.M.J.; Niessen, E.M.J.; Zandbergen, P.J.

    1993-01-01

    Analytical results are presented concerning the electromagnetic response of a composite superconducting wire in fields parallel to the wire axis, using the Maxwell equations supplemented with constitutive equations. The problem is nonlinear due to the nonlinearity in the constitutive equation

  7. Extremely low frequency electromagnetic field in combination with β ...

    African Journals Online (AJOL)

    Fatemeh Sanie-Jahromi

    Extremely low frequency (<300 Hz) electromagnetic field (EMF) is shown to decrease ... Production and hosting by Elsevier B.V. This is an open access article under ..... mouse liver induced by morphine and protected by antioxidants.

  8. Conversion of photons into spinless particles in periodic external electromagnetic field

    International Nuclear Information System (INIS)

    Hoang Ngoc Long; Dang Van Soa

    1996-08-01

    The conversion of photons into axions and dilatons in a periodic external electromagnetic field, namely in the TE 10 mode, are considered in detail. The differential cross sections are given. (author). 16 refs

  9. Investigation of Near-Field Electromagnetic Source Imaging Using Inverse Green's Function Integrations

    National Research Council Canada - National Science Library

    Steenman, Daryl

    1999-01-01

    .... In the far-field of these tested objects, actual sources of high reflectivity or "Hot Spots" on the tested objects can be isolated to within only one half the wavelength of the electromagnetic wave used for testing...

  10. The effect of extreme-low-frequency electromagnetic field on air ...

    African Journals Online (AJOL)

    Electromagnetic fields produce alternating electric fields and modify static electric fields in the vicinity. These electric fields, if large enough, can alter the concentration or transport of airborne particles (including particles harmful to health). In this study, the concentration of radioactive materials (gamma radiation) was ...

  11. The Sterilization Effect of Cooperative Treatment of High Voltage Electrostatic Field and Variable Frequency Pulsed Electromagnetic Field on Heterotrophic Bacteria in Circulating Cooling Water

    Science.gov (United States)

    Gao, Xuetong; Liu, Zhian; Zhao, Judong

    2018-01-01

    Compared to other treatment of industrial circulating cooling water in the field of industrial water treatment, high-voltage electrostatic field and variable frequency pulsed electromagnetic field co-sterilization technology, an advanced technology, is widely used because of its special characteristics--low energy consumption, nonpoisonous and environmentally friendly. In order to get a better cooling water sterilization effect under the premise of not polluting the environment, some experiments about sterilization of heterotrophic bacteria in industrial circulating cooling water by cooperative treatment of high voltage electrostatic field and variable frequency pulsed electromagnetic field were carried out. The comparison experiment on the sterilization effect of high-voltage electrostatic field and variable frequency pulsed electromagnetic field co-sterilization on heterotrophic bacteria in industrial circulating cooling water was carried out by change electric field strength and pulse frequency. The results show that the bactericidal rate is selective to the frequency and output voltage, and the heterotrophic bacterium can only kill under the condition of sweep frequency range and output voltage. When the voltage of the high voltage power supply is 4000V, the pulse frequency is 1000Hz and the water temperature is 30°C, the sterilization rate is 48.7%, the sterilization rate is over 90%. Results of this study have important guiding significance for future application of magnetic field sterilization.

  12. Quantum cosmology of a Bianchi III LRS geometry coupled to a source free electromagnetic field

    Science.gov (United States)

    Karagiorgos, A.; Pailas, T.; Dimakis, N.; Terzis, Petros A.; Christodoulakis, T.

    2018-03-01

    We consider a Bianchi type III axisymmetric geometry in the presence of an electromagnetic field. A first result at the classical level is that the symmetry of the geometry need not be applied on the electromagnetic tensor Fμν the algebraic restrictions, implied by the Einstein field equations to the stress energy tensor Tμν, suffice to reduce the general Fμν to the appropriate form. The classical solution thus found contains a time dependent electric and a constant magnetic charge. The solution is also reachable from the corresponding mini-superspace action, which is strikingly similar to the Reissner-Nordstr{öm one. This points to a connection between the black hole geometry and the cosmological solution here found, which is the analog of the known correlation between the Schwarzschild and the Kantowski-Sachs metrics. The configuration space is drastically modified by the presence of the magnetic charge from a 3D flat to a 3D pp wave geometry. We map the emerging linear and quadratic classical integrals of motion, to quantum observables. Along with the Wheeler-DeWitt equation these observables provide unique, up to constants, wave functions. The employment of a Bohmian interpretation of these quantum states results in deterministic (semi-classical) geometries most of which are singularity free.

  13. Electromagnetically induced transparency in the case of elliptic polarization of interacting fields

    Science.gov (United States)

    Parshkov, Oleg M.

    2018-04-01

    The theoretical investigation results of disintegration effect of elliptic polarized shot probe pulses of electromagnetically induced transparency in the counterintuitive superposed elliptic polarized control field and in weak probe field approximation are presented. It is shown that this disintegration occurs because the probe field in the medium is the sum of two normal modes, which correspond to elliptic polarized pulses with different speeds of propagation. The polarization ellipses of normal modes have equal eccentricities and mutually perpendicular major axes. Major axis of polarization ellipse of one normal mode is parallel to polarization ellipse major axis of control field, and electric vector of this mode rotates in the opposite direction, than electric vector of the control field. The electric vector other normal mode rotates in the same direction that the control field electric vector. The normal mode speed of the first type aforementioned is less than that of the second type. The polarization characteristics of the normal mode depend uniquely on the polarization characteristics of elliptic polarized control field and remain changeless in the propagation process. The theoretical investigation is performed for Λ-scheme of degenerated quantum transitions between 3P0, 3P10 and 3P2 energy levels of 208Pb isotope.

  14. Hearing aids' electromagnetic immunity to environmental RF fields

    International Nuclear Information System (INIS)

    Facta, S.; Benedetto, A.; Anglesio, L.; D'Amore, G.

    2004-01-01

    In this work, the electromagnetic interference on hearing aids was evaluated. Electromagnetic (EM) immunity tests on different types of hearing aids were carried out, using signals of intensity and modulation comparable to those present in the environment. The purpose of this work is to characterise the interference, establishing the immunity threshold for different frequencies and finding out which types of hearing aids are more susceptible, and in which frequency range. The tests were carried out in a GTEM cell on seven hearing aids, using AM and GSM signals in the radiofrequency (RF) range. (authors)

  15. Effect of nonlinear-electrodynamic lagging of electromagnetic signals in the field of magnetic dipole

    International Nuclear Information System (INIS)

    Denisov, V.I.; Krivchenkov, I.V.; Denisov, I.P.

    2002-01-01

    The study on the electromagnetic waves propagation in the neutron star magnetic dipole and gravitation fields, taking place according to the vacuum nonlinear electrodynamics laws, is carried out. It is shown that depending on the polarization the electromagnetic signals in this field propagate by different beams and with various velocities. The law on these signals motion by beams is established. The calculation of differences in the times of the electromagnetic signals propagation, having the same source up to the detector, is presented. It is shown that this difference in some cases may reach enough measurable value of 1 μs [ru

  16. Massive parallel electromagnetic field simulation program JEMS-FDTD design and implementation on jasmin

    International Nuclear Information System (INIS)

    Li Hanyu; Zhou Haijing; Dong Zhiwei; Liao Cheng; Chang Lei; Cao Xiaolin; Xiao Li

    2010-01-01

    A large-scale parallel electromagnetic field simulation program JEMS-FDTD(J Electromagnetic Solver-Finite Difference Time Domain) is designed and implemented on JASMIN (J parallel Adaptive Structured Mesh applications INfrastructure). This program can simulate propagation, radiation, couple of electromagnetic field by solving Maxwell equations on structured mesh explicitly with FDTD method. JEMS-FDTD is able to simulate billion-mesh-scale problems on thousands of processors. In this article, the program is verified by simulating the radiation of an electric dipole. A beam waveguide is simulated to demonstrate the capability of large scale parallel computation. A parallel performance test indicates that a high parallel efficiency is obtained. (authors)

  17. Evaluation Of Electromagnetic Fields For Frequencies 900 MHz-1 800 MHz In Tirana

    OpenAIRE

    Kuqi Dhurata; Malkaj Partizan; Kuka Shklqim; Kuqali Margarita; Hoxha Adhurim; Mulaj Tatjana; Goga Marjola; Dokuzi Hazbi

    2015-01-01

    Abstract The massive use of mobile phone as a communication tool nowadays is accompanied the ever increasing interest of the public and researchers for the possibly impact on human health as a result of exposure to the electromagnetic fields that accompany these devices. Therefore knowing the level of exposure electromagnetic fields of this electronic equipment has been and will be in the future interest object to the public and the subject of study for the researchers. In this paper are pres...

  18. Combination transition radiation in a medium excited by an electromagnetic field

    International Nuclear Information System (INIS)

    Kalashnikova, Yu.S.

    1976-01-01

    The radiation emitted by a uniformly moving charged particle in a medium excited by an electromagnetic field is considered by taking into account the interaction between the electromagnetic waves and optical phonon wave. The frequencies are found, in the vicinity of which the two-wave approximation should be applied in order to determine the radiation field. It is shown that in the vicinity of these frequencies the radiation considerably differs from the Cherenkov radiation

  19. Accurate Modeling of Ionospheric Electromagnetic Fields Generated by a Low Altitude VLF Transmitter

    Science.gov (United States)

    2009-03-31

    AFRL-RV-HA-TR-2009-1055 Accurate Modeling of Ionospheric Electromagnetic Fields Generated by a Low Altitude VLF Transmitter ...m (or even 500 m) at mid to high latitudes . At low latitudes , the FDTD model exhibits variations that make it difficult to determine a reliable...Scientific, Final 3. DATES COVERED (From - To) 02-08-2006 – 31-12-2008 4. TITLE AND SUBTITLE Accurate Modeling of Ionospheric Electromagnetic Fields

  20. Wake-Field Wave Resonant Excitation in Magnetized Plasmas by Electromagnetic Pulse

    International Nuclear Information System (INIS)

    Milant'ev, V.P.; Turikov, V.A.

    2006-01-01

    In this paper the space charge wave excitation process at electromagnetic pulse propagation along external magnetic field in vicinity of electron cyclotron resonance. In hydrodynamic approach it is obtained an equation for plasma density under ponderomotive force action. With help of this equation we investigated a wake-field wave amplitude dependence from resonance detuning. The numerical simulation using a PIC method electromagnetic pulse propagation process in the resonant conditions was done

  1. Nuclear β decay with a massive neutrino in an external electromagnetic field

    International Nuclear Information System (INIS)

    Ternov, I.M.; Rodionov, V.N.; Zhulego, V.G.; Lobanov, A.E.; Pavlova, O.S.; Dorofeev, O.F.

    1986-01-01

    Beta decay in the presence of an external electromagnetic field is investigated, taking into account the non-zero neutrino rest mass. The spectrum of electrons and polarisation effects of different orientations of nuclear spin are considered. It is shown that the electromagnetic wave substantially modifies the boundaries of the spectrum of β electrons. The results, which include an analysis of the total decay probability in intense magnetic fields, may have various astrophysical implications. (author)

  2. Measurement of electromagnetic fields generated by air traffic control radar systems with spectrum analysers.

    Science.gov (United States)

    Barellini, A; Bogi, L; Licitra, G; Silvi, A M; Zari, A

    2009-12-01

    Air traffic control (ATC) primary radars are 'classical' radars that use echoes of radiofrequency (RF) pulses from aircraft to determine their position. High-power RF pulses radiated from radar antennas may produce high electromagnetic field levels in the surrounding area. Measurement of electromagnetic fields produced by RF-pulsed radar by means of a swept-tuned spectrum analyser are investigated here. Measurements have been carried out both in the laboratory and in situ on signals generated by an ATC primary radar.

  3. The views of primary care physicians on health risks from electromagnetic fields

    DEFF Research Database (Denmark)

    Berg-Beckhoff, Gabi; Heyer, Kristina; Kowall, Bernd

    2010-01-01

    The aim of this study was to find out what primary care physicians in Germany think about the possible health risks of electromagnetic fields (EMF) and how they deal with this topic in discussions with patients.......The aim of this study was to find out what primary care physicians in Germany think about the possible health risks of electromagnetic fields (EMF) and how they deal with this topic in discussions with patients....

  4. [Ecological significance of electromagnetic fields: the 20th century--century of electricity, the 21st--century of magnetism].

    Science.gov (United States)

    Lazetić, Bogosav

    2003-01-01

    The biosphere consists of all ecosystems of earth and is characterized by electromagnetic fields of different frequencies. Physics and natural sciences and disciplines are focused on their origin and characteristics. NATURAL ELECTROMAGNETIC FIELDS: There is a well defined idea that natural electromagnetic activity of the Earth's atmosphere throughout evolution led to appearance of electromagnetic homeostasis, i.e. maintenance of inner electromagnetic mileu. It can be supposed that during the evolution of living organisms natural electromagnetic fields were associated with biochemical processes and as a result of natural selection became an important information system and obligatory component of life. The results presented here show that there is no reason to doubt that natural electromagnetic fields are an important ecologic factor. On the contrary, we have to emphasize that natural electromagnetic environment is necessary for life on the Earth. Today intensity of artificial electromagnetic fields is ten to hundred times higher than of natural electromagnetic fields. Danger from electromagnetic fields is an acute and actual problem which increases knowing that there won't be a spot without artificial electromagnetic field on our planet.

  5. Three-dimensional electromagnetic strong turbulence. I. Scalings, spectra, and field statistics

    International Nuclear Information System (INIS)

    Graham, D. B.; Robinson, P. A.; Cairns, Iver H.; Skjaeraasen, O.

    2011-01-01

    The first fully three-dimensional (3D) simulations of large-scale electromagnetic strong turbulence (EMST) are performed by numerically solving the electromagnetic Zakharov equations for electron thermal speeds ν e with ν e /c≥0.025. The results of these simulations are presented, focusing on scaling behavior, energy density spectra, and field statistics of the Langmuir (longitudinal) and transverse components of the electric fields during steady-state strong turbulence, where multiple wave packets collapse simultaneously and the system is approximately statistically steady in time. It is shown that for ν e /c > or approx. 0.17 strong turbulence is approximately electrostatic and can be explained using the electrostatic two-component model. For v e /c > or approx. 0.17 the power-law behaviors of the scalings, spectra, and field statistics differ from the electrostatic predictions and results because ν e /c is sufficiently high to allow transverse modes to become trapped in density wells. The results are compared with those of past 3D electrostatic strong turbulence (ESST) simulations and 2D EMST simulations. For number density perturbations, the scaling behavior, spectra, and field statistics are shown to be only weakly dependent on ν e /c, whereas the Langmuir and transverse scalings, spectra, and field statistics are shown to be strongly dependent on ν e /c. Three-dimensional EMST is shown to have features in common with 2D EMST, such as a two-component structure and trapping of transverse modes which are dependent on ν e /c.

  6. Coupled dilaton and electromagnetic field in cylindrically symmetric ...

    Indian Academy of Sciences (India)

    An exact solution is obtained for coupled dilaton and electromagnetic field in a cylindrically symmetric spacetime where an axial magnetic field as well as a radial electric field both are present. Depending on the choice of the arbitrary constants our solution reduces either to dilatonic gravity with pure electric field or to that ...

  7. Electromagnetically Driven Plasma-Field Dynamics in Modified Ionosphere

    Science.gov (United States)

    Kochetov, Andrey; Terina, Galina

    Under sounding of an artificial ionospheric turbulence by short probing radio pulses of ordinary polarization the two types of scattered signals were observed: a "caviton" signal (CS) and a "plasma" signal (PS), which appeared with the heating transmitter switching on and disap-peared after its switching off (G.I. Terina J. Atm. Terr. Phys, 57, 1995, 273, Izv. VUZov, Radiofizika, 39, 1998, 203). The scattered signal of PS type was revealed also after the heating switching off. It was called an "aftereffect plasma signal" (AEPS) (G.I. Terina Izv .VUZov, Radiofizika, 43, 2000, 958). This signal had large time and spatial delays and appeared mostly when corresponding PS had envelope fluctuations. The aftereffect phenomenon was expressed at time on CS by amplitude increasing at once after the heating transmitter turning off. The theoretical model of this phenomenon is proposed in and some peculiarities of the aftereffect phenomena of the scattered signals in modified ionospheric plasma are considered and discussed. For theoretical interpretation of the characteristics of CS and AEPS the numerical solution of nonlinear Shrüdinger equation (NSE) with driven extension were carried out in inhomogeneous plasma layer with linear electron density profile (A.V. Kochetov, V.A. Mironov, G.I. Terina, Adv. Space Reseacrh, 29, 2002, 1369) and for the one with prescribed density depletion (and A.V. Kochetov, G.I. Terina, Adv. Space Reseacrh, 38, 2006, 2490). The simulation results obtained for linear inhomogeneous plasma layer and for plasma one with density depletion al-low us to interpret the aftereffect of CS and PS qualitatively. The field amplitude increase at relaxation stage displayed at calculations allows us to interpret of CS aftereffect. The large time delays of AEPS can be explained as a result of powerful radio waves trapping in the forming at the plasma resonance regions density depletions (E. Mjøhus, J. Geophys. Res. 103, 1998, 14711; B. Eliasson and L. Stenflo, J

  8. Lagrangian and energy forms for retrieving the impulse response of the Earth due to random electromagnetic forcing.

    Science.gov (United States)

    Slob, Evert; Weiss, Chester J

    2011-08-01

    We distinguish between trivial and nontrivial differences in retrieving the real or imaginary parts of the Green's function. Trivial differences come from different Green's function definitions. The energy and lagrangian forms constitute nontrivial differences. Magnetic noise sources suffice to extract the quasistatic electromagnetic-field Earth impulse response in the lagrangian form. This is of interest for Earth subsurface imaging. A numerical example demonstrates that all source vector components are necessary to extract a single-field vector component.

  9. Low-frequency electromagnetic radiation field interaction with cerebral nervous MT

    International Nuclear Information System (INIS)

    Gao Feng; Zhou Yi; Xiao Detao; Zhang Dengyu

    2009-01-01

    We investigate the interaction characteristics and mechanism of electromagnetic radiation field and cerebral nervous system. When the electromagnetic radiation is non-ionization low-frequency electromagnetic field, the two-state physical system in the cytoskeletal microtubule (MT) can be quantized. The state of information bits in cerebral neurons system is described by density matrix, and the system dynamics equation is established and solved. It indicates that when the brain is exposed to non-ionization low-frequency electromagnetic field, the density matrix non-opposite angle element of cerebral nervous qubit will never be zero, its quantum coherence characteristic can keep well, and the brain function will also be not damaged. (authors)

  10. [Effect of 50 Hz 1.8 mT sinusoidal electromagnetic fields on bone mineral density in growing rats].

    Science.gov (United States)

    Gao, Yu-Hai; Zhou, Yan-Feng; Li, Shao-Feng; Li, Wen-Yuan; Xi, Hui-Rong; Yang, Fang-Fang; Chen, Ke-Ming

    2017-12-25

    To study effects of 50 Hz 1.8 mT sinusoidal electromagnetic fields (SEMFs) on bone mineral density (BMD) in SD rats. Thirty SD rats weighted(110±10) and aged 1 month were randomly divided into control group and electromagnetic field group, 15 in each group. Normal control group of 50 Hz 0 mT density and sinusoidal electromagnetic field group of 50 Hz 1.8 mT were performed respectively with 1.5 h/d and weighted weight once a week, and observed food-intake. Rats were anesthesia by intraperitoneal injection and dual energy X-ray absorptiometry were used to detect bone density of whole body, and detected bone density of femur and vertebral body. Osteocalcin and tartrate-resistant acid phosphatase 5b were detected by ELSA; weighted liver, kidney and uterus to calculate purtenance index, then detected pathologic results by HE. Compared with control group, there was no significant change in weight every week, food-intake every day; no obvious change of bone density of whole body at 2 and 4 weeks, however bone density of whole body, bone density of excised femur and vertebra were increased at 6 weeks. Expression of OC was increased, and TRACP 5b expression was decreased. No change of HE has been observed in liver, kidney and uterus and organic index. 50 Hz 1.8 mT sinusoidal electromagnetic fields could improve bone formation to decrease relevant factors of bone absorbs, to improve peak bone density of young rats, in further provide a basis for clinical research electromagnetic fields preventing osteoporosis foundation.

  11. Proposal to regulate human exposure limits to electromagnetic fields produced by cellular telephony systems in Costa Rica

    International Nuclear Information System (INIS)

    Gomez Lizano, Cristian; Calvo Horth, Gustavo; Dompe Gamboa, Pablo; Ramirez Rodriguez, David; Retana Duran, Elias; Gutierrez Chinchilla, Jose Alcides

    2008-01-01

    Modern society has presented an epic technology development in recent years, driven strongly by communications networks: from micro environments such as personal area networks passing by cell phone to the global Internet network. The communications established in real-time are increasingly, a necessary input. However, the growing demand for communications services and in particularly mobile phone, has meant that the environment is altered by the large number of signals generated by electromagnetic fields that transmit high volumes of energy, which saturate the electromagnetic spectrum, these waves of energy called no ionizing energy. The World Health Organization, through the International Energy Agency Nonionizing (ICNIRP for its acronym in English), has conducted in recent years researches on the effects of the health of people exposed to nonionizing energy; also, have existed proposals regulating these exposure levels. Nonionizing electromagnetic fields are investigated, focusing on transmitting equipment for mobile phone systems in Costa Rica and electromagnetic safety criteria of exposure, both occupational as of general public. The electromagnetism basic concepts and parameters related with nonionizing radiations research are referenced, among them can be mentioned the relationship between the electric field E, the magnetic field H and the power density S. Other concepts such as near-field region, far-field region, exposure zones and specified absorption rate SAR, are also defined. A mathematical fundament is presented showing the relationships between the concepts explained. Guidelines for calculating the power density are provided by means of a theoretical estimate from parameters of transmitting equipment. Also, the procedures for calculating the spatial and temporal averaging are set out and a brief overview is made of epidemiological and biological effects caused by radio frequency radiation. The existing rules at the international level are analyzed to

  12. Electromagnetic field measurements in ULF-ELF-VLF [0.001 Hz─100 KHz] bands

    Directory of Open Access Journals (Sweden)

    C. Di Lorenzo

    2008-01-01

    Full Text Available We are reporting the technological and scientific objectives of the MEM project. The MEM project has been activated in the INGV Observatory of L'Aquila to create in Central Italy a network of observatories in order to monitoring the electromagnetic signals in the frequency band [0.001 Hz–100 kHz]. Some examples of the instrumentation developed in the frame of the project are reported. An innovative technique, based on the wide band interferometry is proposed to obtain detailed information concerning the several detected electromagnetic sources. Moreover, data from each station will be elaborated to investigate different sectors as the structure of ground electric conductibility, the electromagnetic phenomena connected with seismic activity, the separation of the electromagnetic fields originated in the Earth's interior and the electromagnetic phenomena originated in the magnetosphere, in the ionosphere and in the Earth-ionosphere cavity.

  13. Controlling Energy Radiations of Electromagnetic Waves via Frequency Coding Metamaterials.

    Science.gov (United States)

    Wu, Haotian; Liu, Shuo; Wan, Xiang; Zhang, Lei; Wang, Dan; Li, Lianlin; Cui, Tie Jun

    2017-09-01

    Metamaterials are artificial structures composed of subwavelength unit cells to control electromagnetic (EM) waves. The spatial coding representation of metamaterial has the ability to describe the material in a digital way. The spatial coding metamaterials are typically constructed by unit cells that have similar shapes with fixed functionality. Here, the concept of frequency coding metamaterial is proposed, which achieves different controls of EM energy radiations with a fixed spatial coding pattern when the frequency changes. In this case, not only different phase responses of the unit cells are considered, but also different phase sensitivities are also required. Due to different frequency sensitivities of unit cells, two units with the same phase response at the initial frequency may have different phase responses at higher frequency. To describe the frequency coding property of unit cell, digitalized frequency sensitivity is proposed, in which the units are encoded with digits "0" and "1" to represent the low and high phase sensitivities, respectively. By this merit, two degrees of freedom, spatial coding and frequency coding, are obtained to control the EM energy radiations by a new class of frequency-spatial coding metamaterials. The above concepts and physical phenomena are confirmed by numerical simulations and experiments.

  14. An analysis of the electromagnetic field in multi-polar linear induction system

    International Nuclear Information System (INIS)

    Chervenkova, Todorka; Chervenkov, Atanas

    2002-01-01

    In this paper a new method for determination of the electromagnetic field vectors in a multi-polar linear induction system (LIS) is described. The analysis of the electromagnetic field has been done by four dimensional electromagnetic potentials in conjunction with theory of the magnetic loops . The electromagnetic field vectors are determined in the Minkovski's space as elements of the Maxwell's tensor. The results obtained are compared with those got from the analysis made by the finite elements method (FEM).With the method represented in this paper one can determine the electromagnetic field vectors in the multi-polar linear induction system using four-dimensional potential. A priority of this method is the obtaining of analytical results for the electromagnetic field vectors. These results are also valid for linear media. The dependencies are valid also at high speeds of movement. The results of the investigated linear induction system are comparable to those got by the finite elements method. The investigations may be continued in the determination of other characteristics such as drag force, levitation force, etc. The method proposed in this paper for an analysis of linear induction system can be used for optimization calculations. (Author)

  15. Influence of Electric, Magnetic, and Electromagnetic Fields on the Circadian System: Current Stage of Knowledge

    Science.gov (United States)

    Żak, Arkadiusz

    2014-01-01

    One of the side effects of each electrical device work is the electromagnetic field generated near its workplace. All organisms, including humans, are exposed daily to the influence of different types of this field, characterized by various physical parameters. Therefore, it is important to accurately determine the effects of an electromagnetic field on the physiological and pathological processes occurring in cells, tissues, and organs. Numerous epidemiological and experimental data suggest that the extremely low frequency magnetic field generated by electrical transmission lines and electrically powered devices and the high frequencies electromagnetic radiation emitted by electronic devices have a potentially negative impact on the circadian system. On the other hand, several studies have found no influence of these fields on chronobiological parameters. According to the current state of knowledge, some previously proposed hypotheses, including one concerning the key role of melatonin secretion disruption in pathogenesis of electromagnetic field induced diseases, need to be revised. This paper reviews the data on the effect of electric, magnetic, and electromagnetic fields on melatonin and cortisol rhythms—two major markers of the circadian system as well as on sleep. It also provides the basic information about the nature, classification, parameters, and sources of these fields. PMID:25136557

  16. Macroscopic electromagnetic properties of the Irvine Field-Reversed Configuration: Equilibrium, power balance and fluctuations

    Science.gov (United States)

    Trask, Erik Harold

    The plasma parameters and characteristics of the Irvine Field-Reversed Configuration (IFRC) are summarized in this thesis. Particular emphasis is placed on the development of the different diagnostics used to make measurements in the experiment, as well as the measurements themselves. Whenever possible, actual measurements are used in lieu of theoretical or analytical fits to data. Analysis of magnetic probes (B-dots) comprises the bulk of what is known about the IFRC. From these B-dot probes, the magnetic field structure in a two dimensional plane at constant toroidal position has been determined, and has been found to be consistent with a field-reversed configuration. Peak reversed fields of approximately 250 Gauss have been observed. Further analyses have been developed to extract information from the magnetic field structure, including components of the electric field, the current density, and plasma pressure in the same two dimensional plane. Electric field magnitudes reach 600 V/m, concurrent with current densities greater than 105 Amps/m2 and thermal pressures over 200 Pa. Spectroscopic analysis of hydrogen lines has been done to make estimates of the electron temperature, while spectroscopic measurements of the Doppler broadening of the Halpha line31 have allowed an estimate of the ion temperature. Particle losses out one axial end plane measured by an array of Faraday cups quantify the how well the configuration traps particles. Spectral information derived from B-dot probes indicates that there is substantial power present at frequencies lying between the hydrogen cyclotron and mean gyrofrequency. These various measurements are used to find the following parameters that characterize the Irvine FRC: (1) Electromagnetic and thermal stored energies as functions of time. (2) Power balance, including input power from the field coils, resistive heating, power lost by particle transport and radiation, and particle and energy confinement times. (3) Strong

  17. [The effect of electromagnetic fields on living organisms: plants, birds and animals].

    Science.gov (United States)

    Rochalska, Małgorzata

    2007-01-01

    Electromagnetic fields, constant and alternating, are a static element of the environment. They originate from both natural and man-made sources. Depending on the type of the field, its intensity and time of activity, they exert different effects on the natural world (plants and animals). Some animals utilize magnetic field of the earth for their own purposes.

  18. Effects of electromagnetic field of 33 and 275 kv influences on ...

    African Journals Online (AJOL)

    user

    2012-08-16

    Aug 16, 2012 ... vacant land beneath high voltage transmission lines to grow leaf ... Studies on suitability of vegetables beneath power lines ... analysis. Electromagnetic field strength measurement. Electric field (kV/m) and magnetic field (mT) reading were taken at ..... faint extra band at Rf 0.09 in lanes 4 (30 m), 5 (40 m), 6.

  19. Electromagnetic-field equations in the six-dimensional space-time R6

    International Nuclear Information System (INIS)

    Teli, M.T.; Palaskar, D.

    1984-01-01

    Maxwell's equations (without monopoles) for electromagnetic fields are obtained in six-dimensional space-time. The equations possess structural symmetry in space and time, field and source densities. Space-time-symmetric conservation laws and field solutions are obtained. The results are successfully correlated with their four-dimensional space-time counterparts

  20. Sub-wavelength imaging and field mapping via electromagnetically induced transparency and Autler-Townes splitting in Rydberg atoms

    Energy Technology Data Exchange (ETDEWEB)

    Holloway, Christopher L., E-mail: holloway@boulder.nist.gov; Gordon, Joshua A. [National Institute of Standards and Technology (NIST), Electromagnetics Division, U.S. Department of Commerce, Boulder Laboratories, Boulder, Colorado 80305 (United States); Schwarzkopf, Andrew; Anderson, David A.; Miller, Stephanie A.; Thaicharoen, Nithiwadee; Raithel, Georg [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2014-06-16

    We present a technique for measuring radio-frequency (RF) electric field strengths with sub-wavelength resolution. We use Rydberg states of rubidium atoms to probe the RF field. The RF field causes an energy splitting of the Rydberg states via the Autler-Townes effect, and we detect the splitting via electromagnetically induced transparency (EIT). We use this technique to measure the electric field distribution inside a glass cylinder with applied RF fields at 17.04 GHz and 104.77 GHz. We achieve a spatial resolution of ≈100 μm, limited by the widths of the laser beams utilized for the EIT spectroscopy. We numerically simulate the fields in the glass cylinder and find good agreement with the measured fields. Our results suggest that this technique could be applied to image fields on a small spatial scale over a large range of frequencies, up into the sub-terahertz regime.

  1. Simulation of Heat Transfer and Electromagnetic Fields of Protected Microcomputers

    Directory of Open Access Journals (Sweden)

    Josef Lakatos

    2006-01-01

    Full Text Available The paper presents results of collaboration between Department of mechatronics and electronics at University of Žilina and VÚVT Engineering a.s. Žilina in area of heat transfer simulations and disturbing electromagnetic radiation simulations in computer construction. The simulations results were used in development of protected microcomputer prototypes in frame of applied research at both of workplaces.

  2. Occupational medicine and electromagnetic fields; Medecine du travail et champs electromagnetiques

    Energy Technology Data Exchange (ETDEWEB)

    Seze, R. de [Institut National de l' Environnement Industriel et des Risques, 60 - Verneuil en Halatte (INERIS) (France)

    2001-07-01

    Numerous industrial areas are concerned by electromagnetic fields exposures. The most intense sources are constituted by high frequencies. The most known are the relay antenna for cellular radio communications (type GSM). The principal sources of electromagnetic fields are given and the levels fields susceptible to be encountered at working posts. The interaction mechanisms of fields are given in function of frequencies, then the biological effects are studied. The results of epidemiological studies are synthesised. The recommendations in France and in Europe are presented as well the standardisation organisms. (N.C.)

  3. Dynamics of electrons in a parabolic magnetic field perturbed by an electromagnetic wave

    International Nuclear Information System (INIS)

    Neishtadt, Anatoly; Vainchtein, Dmitri; Vasiliev, Alexei

    2011-01-01

    In this paper we study the resonance interaction between monochromatic electromagnetic waves and fully magnetized electrons in a model parabolic magnetic field (like, e.g., in the Earth's magnetotail). The smallness of certain physical parameters allows us to approach this problem using perturbation theory for multiscale (slow-fast) systems: the study of the global interaction is reduced to the analysis of slow passages of particles through a resonance. At the resonance, two important phenomena occur: capture into resonance and scattering on resonance. We show that while the primary adiabatic invariant (magnetic moment or Larmor radius) remains conserved, these processes result in destruction of the second, longitudinal, adiabatic invariant. We find significant acceleration of particles by capture into resonance, while the scatterings on resonances lead to decrease in energy and chaotization of particles.

  4. Degradation of Au–Ti contacts of SiGe HBTs during electromagnetic field stress

    International Nuclear Information System (INIS)

    Alaeddine, A; Genevois, C; Cuvilly, F; Daoud, K; Kadi, M

    2011-01-01

    This paper addresses electromagnetic field stress effects on SiGe heterojunction bipolar transistors (HBTs)' reliability issues, focusing on the relationship between the stress-induced current and device structure degradations. The origin of leakage currents and electrical parameter shifts in failed transistors has been studied by complementary failure analysis techniques. Characterization of the structure before and after ageing was performed by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). For the stressed samples, interface deformations of the titanium (Ti) thin film around all gold (Au) contacts have been clearly detected. These degradations include localized interface reaction between Au and Ti layers as well as their lateral atomic migration causing a significant reduction of Ti thickness. EDS analysis of the disordered region which is near the Si 3 N 4 interface has shown significant signals from Au. These observations could be attributed to the coupling between high current densities induced by stress and thermal effects due to local heating effects

  5. Simulation and testing of a micro electromagnetic energy harvester for self-powered system

    Directory of Open Access Journals (Sweden)

    Yiming Lei

    2014-01-01

    Full Text Available This paper describes a low cost and efficient electromagnetic vibration energy harvester (EVEH for a self-powered system. The EVEH consists of a resistant (copper spring, a permanent magnet (NdFeB35 and a wire-wound copper coil. The copper spring was fabricated by the laser precision cutting technology. A numerical model was adopted to analyze magnetic field distribution of a rectangle permanent magnet. The finite element (FEM soft ANSYS was used to simulate the mechanical properties of the system. The testing results show that the micro electromagnetic vibration energy harvester can generate the maximal power 205.38 μW at a resonance frequency of 124.2 Hz with an acceleration of 0.5 g (g = 9.8 ms−2 across a load the 265 Ω and a superior normalized power density (NPD of 456.5 μW cm−3 g−2. The magnetic field distribution of the permanent magnet was calculated to optimize geometric parameters of the coil. The proposed EVEH has a high efficiency with the lower cost.

  6. FR4-based electromagnetic energy harvester for wireless sensor nodes

    Science.gov (United States)

    Hatipoglu, G.; Ürey, H.

    2010-01-01

    Electromagnetic (EM) energy harvesting seems to be one of the most promising ways to power wireless sensors in a wireless sensor network. In this paper, FR4, the most commonly used PCB material, is utilized as a mechanical vibrating structure for EM energy harvesting for body-worn sensors and intelligent tire sensors, which involve impact loadings. FR4 can be a better material for such applications compared to silicon MEMS devices due to lower stiffness and broadband response. In order to demonstrate FR4 performance and broadband response, three moving magnet type EM generator designs are developed and investigated throughout the paper. A velocity-damped harvester simulation model is first developed, including a detailed magnetic model and the magnetic damping effects. The numerical results agree well with the experimental results. Human running acceleration at the hip area that is obtained experimentally is simulated in order to demonstrate system performance, which results in a scavenged power of about 40 µW with 15 m s-2 acceleration input. The designed FR4 energy scavengers with mechanical stoppers implemented are particularly well suited for nearly periodic and non-sinusoidal high- g excitations with rich harmonic content. For the intelligent tire applications, a special compact FR4 scavenger is designed that is able to withstand large shocks and vibrations due to mechanical shock stoppers built into the structure. Using our design, 0.4 mW power across a load resistance at off-resonance operation is obtained in shaker experiments. In the actual operation, the tangential accelerations as a result of the tire-road contact are estimated to supply power around 1 mW with our design, which is sufficient for powering wireless tire sensors. The normalized power density (NPD) of the designed actuators compares favorably with most actuators reported in the literature.

  7. FR4-based electromagnetic energy harvester for wireless sensor nodes

    International Nuclear Information System (INIS)

    Hatipoglu, G; Ürey, H

    2010-01-01

    Electromagnetic (EM) energy harvesting seems to be one of the most promising ways to power wireless sensors in a wireless sensor network. In this paper, FR4, the most commonly used PCB material, is utilized as a mechanical vibrating structure for EM energy harvesting for body-worn sensors and intelligent tire sensors, which involve impact loadings. FR4 can be a better material for such applications compared to silicon MEMS devices due to lower stiffness and broadband response. In order to demonstrate FR4 performance and broadband response, three moving magnet type EM generator designs are developed and investigated throughout the paper. A velocity-damped harvester simulation model is first developed, including a detailed magnetic model and the magnetic damping effects. The numerical results agree well with the experimental results. Human running acceleration at the hip area that is obtained experimentally is simulated in order to demonstrate system performance, which results in a scavenged power of about 40 µW with 15 m s −2 acceleration input. The designed FR4 energy scavengers with mechanical stoppers implemented are particularly well suited for nearly periodic and non-sinusoidal high- g excitations with rich harmonic content. For the intelligent tire applications, a special compact FR4 scavenger is designed that is able to withstand large shocks and vibrations due to mechanical shock stoppers built into the structure. Using our design, 0.4 mW power across a load resistance at off-resonance operation is obtained in shaker experiments. In the actual operation, the tangential accelerations as a result of the tire–road contact are estimated to supply power around 1 mW with our design, which is sufficient for powering wireless tire sensors. The normalized power density (NPD) of the designed actuators compares favorably with most actuators reported in the literature

  8. Thermally Driven Transport and Relaxation Switching Self-Powered Electromagnetic Energy Conversion.

    Science.gov (United States)

    Cao, Maosheng; Wang, Xixi; Cao, Wenqiang; Fang, Xiaoyong; Wen, Bo; Yuan, Jie

    2018-06-07

    Electromagnetic energy radiation is becoming a "health-killer" of living bodies, especially around industrial transformer substation and electricity pylon. Harvesting, converting, and storing waste energy for recycling are considered the ideal ways to control electromagnetic radiation. However, heat-generation and temperature-rising with performance degradation remain big problems. Herein, graphene-silica xerogel is dissected hierarchically from functions to "genes," thermally driven relaxation and charge transport, experimentally and theoretically, demonstrating a competitive synergy on energy conversion. A generic approach of "material genes sequencing" is proposed, tactfully transforming the negative effects of heat energy to superiority for switching self-powered and self-circulated electromagnetic devices, beneficial for waste energy harvesting, conversion, and storage. Graphene networks with "well-sequencing genes" (w = P c /P p > 0.2) can serve as nanogenerators, thermally promoting electromagnetic wave absorption by 250%, with broadened bandwidth covering the whole investigated frequency. This finding of nonionic energy conversion opens up an unexpected horizon for converting, storing, and reusing waste electromagnetic energy, providing the most promising way for governing electromagnetic pollution with self-powered and self-circulated electromagnetic devices. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Schrödinger Theory of Electrons in Electromagnetic Fields: New Perspectives

    Directory of Open Access Journals (Sweden)

    Viraht Sahni

    2017-03-01

    Full Text Available The Schrödinger theory of electrons in an external electromagnetic field is described from the new perspective of the individual electron. The perspective is arrived at via the time-dependent “Quantal Newtonian” law (or differential virial theorem. (The time-independent law, a special case, provides a similar description of stationary-state theory. These laws are in terms of “classical” fields whose sources are quantal expectations of Hermitian operators taken with respect to the wave function. The laws reveal the following physics: (a in addition to the external field, each electron experiences an internal field whose components are representative of a specific property of the system such as the correlations due to the Pauli exclusion principle and Coulomb repulsion, the electron density, kinetic effects, and an internal magnetic field component. The response of the electron is described by the current density field; (b the scalar potential energy of an electron is the work done in a conservative field. It is thus path-independent. The conservative field is the sum of the internal and Lorentz fields. Hence, the potential is inherently related to the properties of the system, and its constituent property-related components known. As the sources of the fields are functionals of the wave function, so are the respective fields, and, therefore, the scalar potential is a known functional of the wave function; (c as such, the system Hamiltonian is a known functional of the wave function. This reveals the intrinsic self-consistent nature of the Schrödinger equation, thereby providing a path for the determination of the exact wave functions and energies of the system; (d with the Schrödinger equation written in self-consistent form, the Hamiltonian now admits via the Lorentz field a new term that explicitly involves the external magnetic field. The new understandings are explicated for the stationary state case by application to two quantum

  10. Possible health hazards for cardiac pacemaker wearers from exposure to electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    1988-03-01

    Cardiac pacemakers are used to provide electrical stimulation to the heart when the heart's natural rhythm is interrupted. This study shows that they can be susceptible to electromagnetic fields. Pacemakers are well protected against common electromagnetic fields, such as those from household appliances. But intense electomagnetic fields, such as those found in some industrial settings, could affect the functioning of the pacemaker. Such interference may cause the pacemaker wearer to feel dizzy or experience an accelerated heartbeat. While this is not fatal, the pacemaker wearer should try to move away from the source of the interfering field and avoid situations in which interference could arise. After experiencing any of these symptoms, the pacemaker wearer should contact a physician. Potential sources of electromagnetic interference should be identified and characterized to determine if there could be an interference hazard. Exposure to interfering electomagnetic fields should be minimized. 7 refs., 1 fig.

  11. Environmental exposures to electromagnetic fields and health. Opinion note of the Institut de Veille Sanitaire

    International Nuclear Information System (INIS)

    2014-01-01

    This note states the opinion the French Institute for Health Survey (Institut de Veille Sanitaire, InVS) on the effect of electromagnetic fields (used in mobile phones, television and radio broadcasting, radar and satellite communication, or microwave ovens) on health. While distinguishing extremely low frequency and radio-frequency electromagnetic fields, it proposes an overview of acquired knowledge and commonly acknowledged elements on risks for health. It discusses what is supposed or claimed for these both types of fields in terms of carcinogenic and non carcinogenic effects, and also in the particular case of idiopathic environmental intolerance to electromagnetic fields. A third part presents actions undertaken by the InVS (epidemiological survey and field studies), actions to be pursued or supported

  12. A remote monitoring system of environmental electromagnetic field in magnetic confinement fusion test facilities

    International Nuclear Information System (INIS)

    Tanaka, Masahiro; Uda, Tatsuhiko; Takami, Shigeyuki; Wang, Jianqing; Fujiwara, Osamu

    2010-01-01

    A remote, continuous environmental electromagnetic field monitoring system for use in magnetic confinement fusion test facilities is developed. Using this system, both the static magnetic field and the high frequency electromagnetic field could be measured. The required frequency range of the measurement system is from 25 to 100 MHz for the ICRF (Ion Cyclotron Range of Frequencies) heating system. The outputs from the measurement instruments are measured simultaneously by custom-built software using a laptop-type personal computer connected to a local area network. In this way, the electromagnetic field strength could be monitored from a control room located about 200 m from the fusion device building. Examples of measurement data from the vicinity of a high-frequency generator and amplifier and the leakage static magnetic field from a fusion test device are presented. (author)

  13. Scalar and electromagnetic fields in the Kazner metric. Interaction as a mechanism of isotronization

    International Nuclear Information System (INIS)

    Krechet, V.G.; Shikin, G.N.

    1981-01-01

    Within the framework of the Willer-de Vitt superspatial quantization the quantum anisotropic cosmological model with interacting, scalar and electromagnetic fields is considered. It is shown that as a result of direct interaction of the scalar and electromagnetic fields isotropization of the model occurs as in the classical case. While comparing the classical and quantum approaches the conclusion is made that in the quantum approach there are states without initial singularity, that fails in the classical approach; both in the quantum and classical approaches there is isotropization of evolution of the interacting field system (in the quantum approach in α, and β), and in both approaches this process is a consequence of direct interaction of the scalar and electromagnetic fields; in the quantum approach, unlike the classical one, there exists isotropization of the considered model at an infinite growth of the scalar field [ru

  14. Effect of three common sources of electromagnetic fields on health

    Energy Technology Data Exchange (ETDEWEB)

    Mortazavi, S M.J.; Ahmadi, J; Behnejad, B [Rafsanjan Univ. of Medical Sciences, Rafsanjan (Iran, Islamic Republic of)

    2006-07-01

    Background And Aims: The number of people complaining about different symptoms that may be associated with exposure to electromagnetic fields (E.M.F.) has increased rapidly during the past years. Students use both mobile phones and video display terminals frequently. The purpose of this study was to investigate the association of mobile phone use and E.M.F. health hazards. Methods: Basic demographic data and self-reported symptoms were sought using a questionnaire administered to all apparently healthy students at Rafsanjan University of Medical Sciences (R.U.M.S.) and Vali-e-Asr University (V.A.U.). Questions ab out some major confounding factors such as age, gender, amount of video display terminal work were also included. All symptoms were self reported and there was no medical examination. Exact Fisher Test was used for data analysis. Results: 518 complete responses were collected. The responders comprised 317 Vali-e-Asr students (61.2%) and 201 R.U.M.S. students (38.8%). The gender distribution was male 175 33.8%), and female 343 (66.2 %). Thirty percent of the students had been using mobile phones (26% in female students and 38.2% in males, P<0.01). There was a significant difference between the frequency of mobile phone users in medical/par a medical (41.3%) and non-medical (23%) students (P<0. 001). Thirty six percent of the students had been using cord-less phones (no statistically significant gender difference). 56.3% used cathode ray tubes (C.R.T.) as computer monitors (47.1% in female students and 74.3% in males, P<0.001). Regarding self-reported symptoms, headache (52%), fatigue (35%), difficulties in concentration (31.7%), vertigo/dizziness (30%), attention disorders (28.8%), nervousness (28.1%), palpitation (14.7%), low back pain (14.3%), myalgia (12.3%), and tinnitus (10%) were the main self-reported symptoms. There were significantly more women with headache, dizziness, myalgia, and nervousness than men (in each case P<0.001). No significant

  15. Effect of three common sources of electromagnetic fields on health

    International Nuclear Information System (INIS)

    Mortazavi, S.M.J.; Ahmadi, J.; Behnejad, B.

    2006-01-01

    Background And Aims: The number of people complaining about different symptoms that may be associated with exposure to electromagnetic fields (E.M.F.) has increased rapidly during the past years. Students use both mobile phones and video display terminals frequently. The purpose of this study was to investigate the association of mobile phone use and E.M.F. health hazards. Methods: Basic demographic data and self-reported symptoms were sought using a questionnaire administered to all apparently healthy students at Rafsanjan University of Medical Sciences (R.U.M.S.) and Vali-e-Asr University (V.A.U.). Questions ab out some major confounding factors such as age, gender, amount of video display terminal work were also included. All symptoms were self reported and there was no medical examination. Exact Fisher Test was used for data analysis. Results: 518 complete responses were collected. The responders comprised 317 Vali-e-Asr students (61.2%) and 201 R.U.M.S. students (38.8%). The gender distribution was male 175 33.8%), and female 343 (66.2 %). Thirty percent of the students had been using mobile phones (26% in female students and 38.2% in males, P<0.01). There was a significant difference between the frequency of mobile phone users in medical/par a medical (41.3%) and non-medical (23%) students (P<0. 001). Thirty six percent of the students had been using cord-less phones (no statistically significant gender difference). 56.3% used cathode ray tubes (C.R.T.) as computer monitors (47.1% in female students and 74.3% in males, P<0.001). Regarding self-reported symptoms, headache (52%), fatigue (35%), difficulties in concentration (31.7%), vertigo/dizziness (30%), attention disorders (28.8%), nervousness (28.1%), palpitation (14.7%), low back pain (14.3%), myalgia (12.3%), and tinnitus (10%) were the main self-reported symptoms. There were significantly more women with headache, dizziness, myalgia, and nervousness than men (in each case P<0.001). No significant

  16. Electromagnetic processes in strong crystalline fields - NA63 Status Report

    CERN Document Server

    Ugerhoj, Ulrik

    2009-01-01

    Results obtained in the framework of the NA63 experiment cite{Ande05} at CERN are reported. Analysis of the trident production in the strong crystalline fields of single Ge crystals is completed. Yields in the random ('amorphous') orientation are in good agreement with calculations, and in the aligned case the production is enhanced by about a factor 3 compared to a Ge amorphous material. Results on the formation lengths of several microns for the production of GeV photons from ultrarelativistic electrons have been published. In 2008 we performed a measurement of resonance phenomena in structured targets and studied a possible change in restricted energy loss in thin solid state detectors, for sufficiently high values of the Lorentz factor. The plans for 2009 are to study the 'semi-bare electron' from radiation emission in thin targets and to study the spin-flip mechanisms in radiation emission, relevant for beamstrahlung phenomena in future linear colliders such as CLIC.

  17. Absorption of short-pulse electromagnetic energy by a resistively loaded straight wire

    International Nuclear Information System (INIS)

    Miller, E.K.; Deadrick, F.J.; Landt, J.A.

    1975-01-01

    Absorption of short-pulse electromagnetic energy by a resistively loaded straight wire is examined. Energy collected by the wire, load energy, peak load currents, and peak load voltages are found for a wide range of parameters, with particular emphasis on nuclear electromagnetic pulse (EMP) phenomena. A series of time-sequenced plots is used to illustrate pulse propagation on wires when loads and wire ends are encountered

  18. Matrix elements and transition probabilities of interaction of electromagnetic field with a hydrogen-like atom

    International Nuclear Information System (INIS)

    Rajput, B.S.

    1977-01-01

    Using the reduced expansions of second quantized electromagnetic vector potential operator in terms of irreducible representations of Pioncare group in the interaction Hamiltonian, the exact matrix elements of interaction of electromagnetic field with a hydrogenic atom have been derived and the contributions of transitions for different combinations of angular momentum quantum numbers to the transition probabilities of various lines in Lyman-, Balmer-, and Paschen-series have been computed. (author)

  19. Analysis of the fields emitted by mobile communication systems in terms of electromagnetic security

    International Nuclear Information System (INIS)

    Kerimov, E.A.; Abdullayeva, T.M.; Bayramova, Sh.A.; Mardakhayev, A.V.; Khidirov, A.Sh.

    2009-01-01

    The main technical characteristics of digital communication systems of cellular bond are analyzed in this paper.The peculiarities of the electromagnetic fields near the antenna of digital communication systems of cellular bond with frequency, time and code interleaving of subscriber channels.It is shown that it is necessary to pay attention to relative broadbandness of digital signal spectrum on antenna radiation characteristics at carrying out of works on electromagnetic monitoring

  20. Evaluation of Specific Absorption Rate as a Dosimetric Quantity for Electromagnetic Fields Bioeffects

    OpenAIRE

    Panagopoulos, Dimitris J.; Johansson, Olle; Carlo, George L.

    2013-01-01

    PURPOSE: To evaluate SAR as a dosimetric quantity for EMF bioeffects, and identify ways for increasing the precision in EMF dosimetry and bioactivity assessment. METHODS: We discuss the interaction of man-made electromagnetic waves with biological matter and calculate the energy transferred to a single free ion within a cell. We analyze the physics and biology of SAR and evaluate the methods of its estimation. We discuss the experimentally observed non-linearity between electromagnetic exposu...

  1. Modeling and Experimental Verification of an Electromagnetic and Piezoelectric Hybrid Energy Harvester

    Directory of Open Access Journals (Sweden)

    Fan Yuanyuan

    2016-11-01

    Full Text Available This paper describes mathematical models of an electromagnetic and piezoelectric hybrid energy harvesting system and provides an analysis of the relationship between the resonance frequency and the configuration parameters of the system. An electromagnetic and piezoelectric energy harvesting device was designed and the experimental results showed good agreement with the analytical results. The maximum load power of the hybrid energy harvesting system achieved 4.25 mW at a resonant frequency of 18 Hz when the acceleration was 0.7 g, which is an increase of 15% compared with the 3.62 mW achieved by a single electromagnetic technique.

  2. PENTrack-a simulation tool for ultracold neutrons, protons, and electrons in complex electromagnetic fields and geometries

    Science.gov (United States)

    Schreyer, W.; Kikawa, T.; Losekamm, M. J.; Paul, S.; Picker, R.

    2017-06-01

    Modern precision experiments trapping low-energy particles require detailed simulations of particle trajectories and spin precession to determine systematic measurement limitations and apparatus deficiencies. We developed PENTrack, a tool that allows to simulate trajectories of ultracold neutrons and their decay products-protons and electrons-and the precession of their spins in complex geometries and electromagnetic fields. The interaction of ultracold neutrons with matter is implemented with the Fermi-potential formalism and diffuse scattering using Lambert and microroughness models. The results of several benchmark simulations agree with STARucn v1.2, uncovered several flaws in Geant4 v10.2.2, and agree with experimental data. Experiment geometry and electromagnetic fields can be imported from commercial computer-aided-design and finite-element software. All simulation parameters are defined in simple text files allowing quick changes. The simulation code is written in C++ and is freely available at github.com/wschreyer/PENTrack.git.

  3. PENTrack—a simulation tool for ultracold neutrons, protons, and electrons in complex electromagnetic fields and geometries

    Energy Technology Data Exchange (ETDEWEB)

    Schreyer, W., E-mail: w.schreyer@tum.de [Technical University of Munich, James-Franck-Str. 1, 85748 Garching (Germany); Kikawa, T. [TRIUMF, 4004 Wesbrook Mall, Vancouver (Canada); Losekamm, M.J.; Paul, S. [Technical University of Munich, James-Franck-Str. 1, 85748 Garching (Germany); Picker, R. [TRIUMF, 4004 Wesbrook Mall, Vancouver (Canada); Simon Fraser University, 8888 University Drive, Burnaby (Canada)

    2017-06-21

    Modern precision experiments trapping low-energy particles require detailed simulations of particle trajectories and spin precession to determine systematic measurement limitations and apparatus deficiencies. We developed PENTrack, a tool that allows to simulate trajectories of ultracold neutrons and their decay products—protons and electrons—and the precession of their spins in complex geometries and electromagnetic fields. The interaction of ultracold neutrons with matter is implemented with the Fermi-potential formalism and diffuse scattering using Lambert and microroughness models. The results of several benchmark simulations agree with STARucn v1.2, uncovered several flaws in Geant4 v10.2.2, and agree with experimental data. Experiment geometry and electromagnetic fields can be imported from commercial computer-aided-design and finite-element software. All simulation parameters are defined in simple text files allowing quick changes. The simulation code is written in C++ and is freely available at (github.com/wschreyer/PENTrack.git).

  4. Electromagnetic Energy Converters - Rotating Motors and Linear Generators

    Energy Technology Data Exchange (ETDEWEB)

    Ekergaard, Boel

    2011-07-01

    This licentiate thesis presents a study of the electromagnetic properties of linear synchronous permanent magnet generators, utilized in wave energy converters, and a two pole permanent magnet motor for an electrical vehicle. Both machine topologies are presented, designed with a numerical simulation tool, based on a model derived from Maxwell's equations. Full scale prototypes of both the machines are under construction. A continued study about the impact on the magnetic circuit caused by the longitudinal ends of a linear generator is performed. The results present significant core losses in the translator and an increased cogging force caused by the longitudinal ends. Further, a new electric conversion circuit based on the electric resonance phenomena is presented. Experimental results indicate that a successful electric resonance between the generator and external circuit has been achieved. Finally, detailed analytical and numerical methods are utilized to investigate the losses in the two pole permanent magnet motor over a wide frequency interval. The results indicate that the efficiency of electrical motors in electrical vehicle system can be increased relative existing designs and argue for limiting of the gearbox. The system total efficiency and mechanical stability can thereby be increased. The work concerning the wave energy converter is a part of a larger project, the so called Lysekil Wave Power Project, whereas the work concerning the electric motor so far has been carried out as an individual project. However, a future goal is to integrate the research on the electric motor for electrical vehicle with closely related ongoing research regarding a flywheel based electric driveline for an All Electric Propulsion System

  5. Broadband Control of Topological Nodes in Electromagnetic Fields

    Science.gov (United States)

    Song, Alex Y.; Catrysse, Peter B.; Fan, Shanhui

    2018-05-01

    We study topological nodes (phase singularities) in electromagnetic wave interactions with structures. We show that, when the nodes exist, it is possible to bind certain nodes to a specific plane in the structure by a combination of mirror and time-reversal symmetry. Such binding does not rely on any resonances in the structure. As a result, the nodes persist on the plane over a wide wavelength range. As an implication of such broadband binding, we demonstrate that the topological nodes can be used for hiding of metallic objects over a broad wavelength range.

  6. Theory of charged vector mesons interacting with the electromagnetic field

    International Nuclear Information System (INIS)

    Lee, T.D.; Yang, C.N.

    1983-01-01

    It is shown that starting from the usual canonical formalism for the electromagnetic interaction of a charged vector meson with arbitrary magnetic moment one is led to a set of rules for Feynman diagrams, which appears to contain terms that are both infinite and noncovariant. These difficulties, however, can be circumvented by introducing a xi-limiting process which depends on a dimensionless positive parameter xi → 0. Furthermore, by using the mathematical artifice of a negative metric the theory becomes renormalizable (for xi > 0)

  7. Induced polarization and electromagnetic field surveys of sedimentary uranium deposits

    International Nuclear Information System (INIS)

    Campbell, D.L.; Smith, B.D.

    1985-01-01

    Induced polarization (IP) and electromagnetic (EM) geophysical surveys were made over three areas of sedimentary uranium deposits in the western United States. The EM techniques were sometimes useful for investigating general structural settings, but not for finding uranium deposits per se. IP techniques were useful to help pinpoint zones of disseminated pyrite associated with the uranium deposits. In one case no clear differences were seen between the IP signatures of oxidized and reduced ground. Spectral (multi-frequency) IP showed no particular advantages over conventional IP for exploration applications. A sediment mineralization factor is introduced comparable to the ''metal factor'' used to detect porphyry copper mineralization. (author)

  8. Electromagnetic holographic sensitivity field of two-phase flow in horizontal wells

    Science.gov (United States)

    Zhang, Kuo; Wu, Xi-Ling; Yan, Jing-Fu; Cai, Jia-Tie

    2017-03-01

    Electromagnetic holographic data are characterized by two modes, suggesting that image reconstruction requires a dual-mode sensitivity field as well. We analyze an electromagnetic holographic field based on tomography theory and Radon inverse transform to derive the expression of the electromagnetic holographic sensitivity field (EMHSF). Then, we apply the EMHSF calculated by using finite-element methods to flow simulations and holographic imaging. The results suggest that the EMHSF based on the partial derivative of radius of the complex electric potential φ is closely linked to the Radon inverse transform and encompasses the sensitivities of the amplitude and phase data. The flow images obtained with inversion using EMHSF better agree with the actual flow patterns. The EMHSF overcomes the limitations of traditional single-mode sensitivity fields.

  9. Charged particle spin flip in a storage ring with HF-electromagnetic field

    International Nuclear Information System (INIS)

    Polunin, A.A.; Shatupov, Yu.M.

    1982-01-01

    An experiment for revealing a possibility of adiabatic electron spin flip in the VEPP-2M storage ring is described. High frequency longitudinal magnetic field up to 100 Gs at the length of 40 cm and frequency of 7.95 MHz was produced by a spiral of 10 coils supplied from HF-generator with 5 kW power. The control system permitted to vary generator frequency within +-3x10 - 3 f range during 10 - 3 -10 s. Determination of beam polarization degree was exercised by detection of electron elastic scattering inside the bunch. A possibility of changing the polarization sign at preservation of other beam parameters (dimensions, currents, energy, etc.) is of interest in experiments with polarized particles in storage rings. Spin flip can be exercised by effect on the beam of high frequency electromagnetic field, resonance with spin precession frequency around the leading field of the storage ring. The polarized 5 mA beam was produced due to radiation polarization at which electron spins are alinged along the direction of the magnetic field. Processing of the experimental results revealed good correspondence to analytical dependence. The depolarization value at the spin flip did not exceed 10%

  10. Field Flows of Dark Energy

    Energy Technology Data Exchange (ETDEWEB)

    Cahn, Robert N.; de Putter, Roland; Linder, Eric V.

    2008-07-08

    Scalar field dark energy evolving from a long radiation- or matter-dominated epoch has characteristic dynamics. While slow-roll approximations are invalid, a well defined field expansion captures the key aspects of the dark energy evolution during much of the matter-dominated epoch. Since this behavior is determined, it is not faithfully represented if priors for dynamical quantities are chosen at random. We demonstrate these features for both thawing and freezing fields, and for some modified gravity models, and unify several special cases in the literature.

  11. Interaction of the superconducting domains induced by external electric field with electromagnetic waves

    International Nuclear Information System (INIS)

    Shapiro, B.Y.

    1992-01-01

    The behavior of a superconductor in time-independent electric field perpendicular to the surface and in the external electromagnetic wave is theoretically investigated. A new type of the resonance interaction between superconducting domains localized along the magnetic field (if the superconducting phase transition takes place in the external magnetic field perpendicular to the surface) and electromagnetic waves is predicted. The surface impedance of the superconductor with domains is calculated. It is shown that the real part of the impedance has a saturation if the skin length equals the domain size. (orig.)

  12. Design and numerical simulation of the electromagnetic field of linear anode layer ion source

    International Nuclear Information System (INIS)

    Wang Lisheng; Tang Deli; Cheng Changming

    2006-01-01

    The principle of anode layer ion source for etching, pre-cleaning and ion beam assisted deposition was described. The influence of the magnetic field on the performance of anode layer ion source was analyzed. Design of the magnetic loop for the linear anode layer ion source was given. The electromagnetic field distribution of the ion source was simulated by means of ANSYS code and the simulation results were in agreement with experimental ones. The numerical simulation results of the electromagnetic field are useful for improving the anode layer ion source. (authors)

  13. Electromagnetic force on a brane

    International Nuclear Information System (INIS)

    Li, Li-Xin

    2016-01-01

    A fundamental assumption in the theory of brane world is that all matter and radiation are confined on the four-dimensional brane and only gravitons can propagate in the five-dimensional bulk spacetime. The brane world theory did not provide an explanation for the existence of electromagnetic fields and the origin of the electromagnetic field equation. In this paper, we propose a model for explaining the existence of electromagnetic fields on a brane and deriving the electromagnetic field equation. Similar to the case in Kaluza–Klein theory, we find that electromagnetic fields and the electromagnetic field equation can be derived from the five-dimensional Einstein field equation. However, the derived electromagnetic field equation differs from the Maxwell equation by containing a term with the electromagnetic potential vector coupled to the spacetime curvature tensor. So it can be considered as generalization of the Maxwell equation in a curved spacetime. The gravitational field equation on the brane is also derived with the stress–energy tensor for electromagnetic fields explicitly included and the Weyl tensor term explicitly expressed with matter fields and their derivatives in the direction of the extra-dimension. The model proposed in the paper can be regarded as unification of electromagnetic and gravitational interactions in the framework of brane world theory. (paper)

  14. The nonextensive parameter for nonequilibrium electron gas in an electromagnetic field

    International Nuclear Information System (INIS)

    Yu, Haining; Du, Jiulin

    2014-01-01

    The nonextensive parameter for nonequilibrium electron gas of the plasma in an electromagnetic field is studied. We exactly obtained an expression of the q-parameter based on Boltzmann kinetic theories for plasmas, where Coulombian interactions and Lorentz forces play dominant roles. We show that the q-parameter different from unity is related by an equation to temperature gradient, electric field strength, magnetic induction as well as overall bulk velocity of the gas. The effect of the magnetic field on the q-parameter depends on the overall bulk velocity. Thus the q-parameter for the electron gas in an electromagnetic field represents the nonequilibrium nature or nonisothermal configurations of the plasma with electromagnetic interactions. - Highlights: • An expression of the q-parameter is obtained for nonequilibrium plasma with electromagnetic interactions. • The q-parameter is related to temperature gradient, electric field strength, magnetic induction as well as overall bulk velocity of the plasma. • The q-parameter represents the nonequilibrium nature of the complex plasma with electromagnetic interactions

  15. The nonextensive parameter for nonequilibrium electron gas in an electromagnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Haining; Du, Jiulin, E-mail: jldu@tju.edu.cn

    2014-11-15

    The nonextensive parameter for nonequilibrium electron gas of the plasma in an electromagnetic field is studied. We exactly obtained an expression of the q-parameter based on Boltzmann kinetic theories for plasmas, where Coulombian interactions and Lorentz forces play dominant roles. We show that the q-parameter different from unity is related by an equation to temperature gradient, electric field strength, magnetic induction as well as overall bulk velocity of the gas. The effect of the magnetic field on the q-parameter depends on the overall bulk velocity. Thus the q-parameter for the electron gas in an electromagnetic field represents the nonequilibrium nature or nonisothermal configurations of the plasma with electromagnetic interactions. - Highlights: • An expression of the q-parameter is obtained for nonequilibrium plasma with electromagnetic interactions. • The q-parameter is related to temperature gradient, electric field strength, magnetic induction as well as overall bulk velocity of the plasma. • The q-parameter represents the nonequilibrium nature of the complex plasma with electromagnetic interactions.

  16. High-latitude electromagnetic and particle energy flux during an event with sustained strongly northward IMF

    Directory of Open Access Journals (Sweden)

    H. Korth

    2005-06-01

    Full Text Available We present a case study of a prolonged interval of strongly northward orientation of the interplanetary magnetic field on 16 July 2000, 16:00-19:00 UT to characterize the energy exchange between the magnetosphere and ionosphere for conditions associated with minimum solar wind-magnetosphere coupling. With reconnection occurring tailward of the cusp under northward IMF conditions, the reconnection dynamo should be separated from the viscous dynamo, presumably driven by the Kelvin-Helmholtz (KH instability. Thus, these conditions are also ideal for evaluating the contribution of a viscous interaction to the coupling process. We derive the two-dimensional distribution of the Poynting vector radial component in the northern sunlit polar ionosphere from magnetic field observations by the constellation of Iridium satellites together with drift meter and magnetometer observations from the Defense Meteorological Satellite Program (DMSP F13 and F15 satellites. The electromagnetic energy flux is then compared with the particle energy flux obtained from auroral images taken by the far-ultraviolet (FUV instrument on the Imager for Magnetopause to Aurora Global Exploration (IMAGE spacecraft. The electromagnetic energy input to the ionosphere of 51 GW calculated from the Iridium/DMSP observations is eight times larger than the 6 GW due to particle precipitation all poleward of 78° MLAT. This result indicates that the energy transport is significant, particularly as it is concentrated in a small region near the magnetic pole, even under conditions traditionally considered to be quiet and is dominated by the electromagnetic flux. We estimate the contributions of the high and mid-latitude dynamos to both the Birkeland currents and electric potentials finding that high-latitude reconnection accounts for 0.8 MA and 45kV while we attribute <0.2MA and ~5kV to an interaction at lower latitudes having the sense of a viscous interaction. Given that these

  17. Alkali Rydberg states in electromagnetic fields: computational physics meets experiment

    International Nuclear Information System (INIS)

    Krug, A.

    2001-11-01

    We study highly excited hydrogen and alkali atoms ('Rydberg states') under the influence of a strong microwave field. As the external frequency is comparable to the highly excited electron's classical Kepler frequency, the external field induces a strong coupling of many different quantum mechanical energy levels and finally leads to the ionization of the outer electron. While periodically driven atomic hydrogen can be seen as a paradigm of quantum chaotic motion in an open (decaying) quantum system, the presence of the non-hydrogenic atomic core - which unavoidably has to be treated quantum mechanically - entails some complications. Indeed, laboratory experiments show clear differences in the ionization dynamics of microwave driven hydrogen and non-hydrogenic Rydberg states. In the first part of this thesis, a machinery is developed that allows for numerical experiments on alkali and hydrogen atoms under precisely identical laboratory conditions. Due to the high density of states in the parameter regime typically explored in laboratory experiments, such simulations are only possible with the most advanced parallel computing facilities, in combination with an efficient parallel implementation of the numerical approach. The second part of the thesis is devoted to the results of the numerical experiment. We identify and describe significant differences and surprising similarities in the ionization dynamics of atomic hydrogen as compared to alkali atoms, and give account of the relevant frequency scales that distinguish hydrogenic from non-hydrogenic ionization behavior. Our results necessitate a reinterpretation of the experimental results so far available, and solve the puzzle of a distinct ionization behavior of periodically driven hydrogen and non-hydrogenic Rydberg atoms - an unresolved question for about one decade. Finally, microwave-driven Rydberg states will be considered as prototypes of open, complex quantum systems that exhibit a complicated temporal decay

  18. A high-order relativistic two-fluid electrodynamic scheme with consistent reconstruction of electromagnetic fields and a multidimensional Riemann solver for electromagnetism

    International Nuclear Information System (INIS)

    Balsara, Dinshaw S.; Amano, Takanobu; Garain, Sudip; Kim, Jinho

    2016-01-01

    always divergence-free. This collocation also ensures that electromagnetic radiation that is propagating in a vacuum has both electric and magnetic fields that are exactly divergence-free. Coupled relativistic fluid dynamic equations are solved for the positively and negatively charged fluids. The fluids' numerical fluxes also provide a self-consistent current density for the update of the electric field. Our reconstruction strategy ensures that fluid velocities always remain sub-luminal. Our third innovation consists of an efficient design for several popular IMEX schemes so that they provide strong coupling between the finite-volume-based fluid solver and the electromagnetic fields at high order. This innovation makes it possible to efficiently utilize high order IMEX time update methods for stiff source terms in the update of high order finite-volume methods for hyperbolic conservation laws. We also show that this very general innovation should extend seamlessly to Runge–Kutta discontinuous Galerkin methods. The IMEX schemes enable us to use large CFL numbers even in the presence of stiff source terms. Several accuracy analyses are presented showing that our method meets its design accuracy in the MHD limit as well as in the limit of electromagnetic wave propagation. Several stringent test problems are also presented. We also present a relativistic version of the GEM problem, which shows that our algorithm can successfully adapt to challenging problems in high energy astrophysics.

  19. A high-order relativistic two-fluid electrodynamic scheme with consistent reconstruction of electromagnetic fields and a multidimensional Riemann solver for electromagnetism

    Energy Technology Data Exchange (ETDEWEB)

    Balsara, Dinshaw S., E-mail: dbalsara@nd.edu [Physics Department, University of Notre Dame (United States); Amano, Takanobu, E-mail: amano@eps.s.u-tokyo.ac.jp [Department of Earth and Planetary Science, University of Tokyo, Tokyo 113-0033 (Japan); Garain, Sudip, E-mail: sgarain@nd.edu [Physics Department, University of Notre Dame (United States); Kim, Jinho, E-mail: jkim46@nd.edu [Physics Department, University of Notre Dame (United States)

    2016-08-01

    always divergence-free. This collocation also ensures that electromagnetic radiation that is propagating in a vacuum has both electric and magnetic fields that are exactly divergence-free. Coupled relativistic fluid dynamic equations are solved for the positively and negatively charged fluids. The fluids' numerical fluxes also provide a self-consistent current density for the update of the electric field. Our reconstruction strategy ensures that fluid velocities always remain sub-luminal. Our third innovation consists of an efficient design for several popular IMEX schemes so that they provide strong coupling between the finite-volume-based fluid solver and the electromagnetic fields at high order. This innovation makes it possible to efficiently utilize high order IMEX time update methods for stiff source terms in the update of high order finite-volume methods for hyperbolic conservation laws. We also show that this very general innovation should extend seamlessly to Runge–Kutta discontinuous Galerkin methods. The IMEX schemes enable us to use large CFL numbers even in the presence of stiff source terms. Several accuracy analyses are presented showing that our method meets its design accuracy in the MHD limit as well as in the limit of electromagnetic wave propagation. Several stringent test problems are also presented. We also present a relativistic version of the GEM problem, which shows that our algorithm can successfully adapt to challenging problems in high energy astrophysics.

  20. Effects of electromagnetic field of 33 and 275 kV influences on ...

    African Journals Online (AJOL)

    The effects of electromagnetic fields (EMF) from 33 and 275 kV high voltage transmission line on biochemical and antioxidant system changes in mustard leaf (Brassica chinensis) were investigated under field condition. Mustard leaves were exposed to EMF from power lines at distances of 0, 3, 6, 9, 10, 12, 15, 18, 20, 21, ...