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1

Method for imaging with low frequency electromagnetic fields  

DOE Patents [OSTI]

A method is described 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 travel times 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. 13 figures.

Lee, K.H.; Xie, G.Q.

1994-12-13T23:59:59.000Z

2

Method for imaging with low frequency electromagnetic fields  

DOE Patents [OSTI]

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.

Lee, Ki H. (Lafayette, CA); Xie, Gan Q. (Berkeley, CA)

1994-01-01T23:59:59.000Z

3

Increased protein synthesis by cells exposed to a 1,800-MHz radio-frequency mobile phone electromagnetic field, detected by proteome profiling  

Science Journals Connector (OSTI)

To investigate whether or not low intensity radio frequency electromagnetic field exposure (RF-EME) associated...

Christopher Gerner; Verena Haudek

2010-08-01T23:59:59.000Z

4

Calcium homeostasis of isolated heart muscle cells exposed to pulsed high-frequency electromagnetic fields  

SciTech Connect (OSTI)

The intracellular calcium concentration ([Ca{sup 2+}]{sub i}) of isolated ventricular cardiac myocytes of the guinea pig was measured during the application of pulsed high-frequency electromagnetic fields. The high-frequency fields were applied in a transverse electromagnetic cell designed to allow microscopic observation of the myocytes during the presence of the high-frequency fields. The [Ca{sup 2+}]{sub i} was measured as fura-2 fluorescence by means of digital image analysis. Both the carrier frequency and the square-wave pulse-modulation pattern were varied during the experiments (carrier frequencies: 900, 1,300, and 1,800 MHz pulse modulated at 217 Hz with 14% duty cycle; pulsation pattern at 900 MHz; continuous wave, 16 Hz,and 50 Hz modulation with 50% duty cycle and 30 kHz modulation with 80% duty cycle). The mean specific absorption rate (SAR) values in the solution were within one order of magnitude of 1 mW/kg. They varied depending on the applied carrier frequency and pulse pattern. The experiments were designed in three phases: 500 s of sham exposure, followed by 500 s of field exposure, then chemical stimulation without field. The chemical stimulation (K{sup +}-depolarization) indicated the viability of the cells. The K{sup +} depolarization yielded a significant increase in [Ca{sup 2+}]{sub i}. Significant differences between sham exposure and high-frequency field exposure were not found except when a very small but statistically significant difference was detected in the case of 900 MHz/50 Hz. However, this small difference was not regarded as a relevant effect of the exposure.

Wolke, S.; Gollnick, F.; Meyer, R. [Univ. Bonn (Germany)] [Univ. Bonn (Germany); Neibig, U.; Elsner, R. [Inst. fuer Nachrichtentechnik Braunschweig (Germany)] [Inst. fuer Nachrichtentechnik Braunschweig (Germany)

1996-05-01T23:59:59.000Z

5

Determination of High-Frequency Current Distribution Using EMTP-Based Transmission Line Models with Resulting Radiated Electromagnetic Fields  

SciTech Connect (OSTI)

Application of BPL technologies to existing overhead high-voltage power lines would benefit greatly from improved simulation tools capable of predicting performance - such as the electromagnetic fields radiated from such lines. Existing EMTP-based frequency-dependent line models are attractive since their parameters are derived from physical design dimensions which are easily obtained. However, to calculate the radiated electromagnetic fields, detailed current distributions need to be determined. This paper presents a method of using EMTP line models to determine the current distribution on the lines, as well as a technique for using these current distributions to determine the radiated electromagnetic fields.

Mork, B; Nelson, R; Kirkendall, B; Stenvig, N

2009-11-30T23:59:59.000Z

6

Dangerous electromagnetic fields?  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dangerous electromagnetic fields? Dangerous electromagnetic fields? Name: Tommy T Joseph Location: N/A Country: N/A Date: N/A Question: Why are electromagnetic fields supposedly dangerous? Replies: I assume you are asking about power line frequency (60 Hz) fields, since they have been in the news lately. No one knows for sure that they are dangerous. There have been a few studies which seem to show an association between how close homes are to power lines, and the incidence of childhood cancer (mostly leukemia) in children living (or who have lived) in those homes. Other similar studies have not found such an association. In all the studies which have found an association, none has actually measured the fields. Studies which actually have measured the fields find no association. There is no known mechanism for 60 Hz fields to cause cancer. Furthermore, the classic "dose-response relationship," that is, the greater the dose, the greater the response, does not seem to work here. Many laboratory studies have found that 60 Hz fields have an effect on organisms under certain conditions, but none of the observed effects can be convincingly related to a hazard. The bottom line is, no one knows for sure. It is important to realize that it is impossible to prove that anything is completely safe. My personal opinion is that, if there is a risk, it must be very small, or it wouldn't be so hard to prove. I can supply some good unbiased references if you are interested.

7

Coherent hybrid electromagnetic field imaging  

DOE Patents [OSTI]

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.

Cooke, Bradly J. (Jemez Springs, NM); Guenther, David C. (Los Alamos, NM)

2008-08-26T23:59:59.000Z

8

Occupational and residential 60-Hz electromagnetic fields and high-frequency electric transients: exposure assessment using a new dosimeter  

SciTech Connect (OSTI)

One problem that has limited past epidemiologic studies of cancer and exposure to extremely low-frequency (0-100 Hz) electric and magnetic fields has been the lack of adequate methods for assessing personal exposure to these fields. A new 60-Hz electromagnetic field dosimeter was tested to assess occupational and residential exposures of a group of electrical utility workers and a comparison background group over a 7-day period. Comparing work periods only, utility workers' exposures were significantly higher than background levels by a factor of about 10 for electric (E) and magnetic (B) fields and by a factor of 171 for high-frequency transient electric (HFTE) fields. When overall weekly time-weighted averages combining work and nonwork exposures were compared, ratios of the exposed to background groups were lower. B and HFTE exposure ratios remained statistically significant, with values of 3.5 and 58, respectively, whereas the electric field exposure ratio was no longer significant, with a value of 1.7. E-field exposures of the background group were the highest during the nonwork period, probably reflecting the use of electrical appliances at home. Residential E- and B-field exposures were in the same range as published results from other surveys, whereas occupational E-field exposures tended to be lower than exposures reported in other studies. The high variability associated with occupational exposures probably accounts for the latter discrepancy. Worker acceptance of wearing the dosimeter was good: 95% of participants found it to be of little or no inconvenience while at work. At home, 37% found the device to be inconvenient in its present form but would not object to wearing a slightly smaller and lighter dosimeter.

Deadman, J.E.; Camus, M.; Armstrong, B.G.; Heroux, P.; Cyr, D.; Plante, M.; Theriault, G.

1988-08-01T23:59:59.000Z

9

Effect of Cyclotron Resonance Frequencies in Particles Due to AC and DC Electromagnetic Fields  

E-Print Network [OSTI]

and Environmental Engineering, The University of Melbourne, VIC 3010, Australia Department of Electrical and Electronic Engineering, University of Peradeniya, Peradeniya, Srilanka Email: malka and ion cyclotron resonance (ICR) frequencies which is derived from ionic charge to mass ratio is evident

Halgamuge, Malka N.

10

On the electromagnetic fields produced by marine frequency domain controlled sources  

Science Journals Connector (OSTI)

......time-averaged flow of energy through the structure...that a producing offshore petroleum field could...Troll gas field off Norway; Johansen et al...time-averaged flow of energy through a structure...fluctuations induced by wind waves on the deep-sea...by magnetometric offshore electrical sounding......

Alan D. Chave

2009-12-01T23:59:59.000Z

11

Definition: Frequency-Domain Electromagnetics Survey | Open Energy  

Open Energy Info (EERE)

Frequency-Domain Electromagnetics Survey Frequency-Domain Electromagnetics Survey Jump to: navigation, search Dictionary.png Frequency-Domain Electromagnetics Survey Frequency-domain electromagnetic techniques are continuous wave field methods which enable the mapping of the electrical conductivity of the subsurface through electromagnetic induction.[1] View on Wikipedia Wikipedia Definition Electromagnetic induction is the production of a potential difference (voltage) across a conductor when it is exposed to a varying magnetic field. Michael Faraday is generally credited with the discovery of induction in 1831 though it may have been anticipated by the work of Francesco Zantedeschi in 1829. Around 1830 to 1832, Joseph Henry made a similar discovery, but did not publish his findings until later. Faraday's

12

Electromagnetic Field Theory  

E-Print Network [OSTI]

physicists around the world and from WWW `hit' statistics it seems that the book serves as a frequently used formulation of classical electrodynamics, force, momentum and energy of the electromagnetic field, radiation and scope to make it useful in higher university education anywhere in the world, it was produced within

Hart, Gus

13

Definition: Frequency-Domain Electromagnetic Survey | Open Energy  

Open Energy Info (EERE)

Electromagnetic Survey Electromagnetic Survey Jump to: navigation, search Dictionary.png Frequency-Domain Electromagnetic Survey Frequency-domain electromagnetic techniques are continuous wave field methods which enable the mapping of the electrical conductivity of the subsurface through electromagnetic induction.[1] Also Known As Controlled-Source EM References ↑ http://library.seg.org/doi/pdf/10.1190/1.1441531 Ret LikeLike UnlikeLike You like this.Sign Up to see what your friends like. rieved from "http://en.openei.org/w/index.php?title=Definition:Frequency-Domain_Electromagnetic_Survey&oldid=591411" Category: Definitions What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs Linked Data Developer services

14

Torsion and the Electromagnetic Field  

E-Print Network [OSTI]

In the framework of the teleparallel equivalent of general relativity, we study the dynamics of a gravitationally coupled electromagnetic field. It is shown that the electromagnetic field is able not only to couple to torsion, but also, through its energy-momentum tensor, to produce torsion. Furthermore, it is shown that the coupling of the electromagnetic field with torsion preserves the local gauge invariance of Maxwell's theory.

V. C. de Andrade; J. G. Pereira

1999-01-11T23:59:59.000Z

15

Electromagnetic field and cosmic censorship  

E-Print Network [OSTI]

We construct a gedanken experiment in which an extremal Kerr black hole interacts with a test electromagnetic field. Using Teukolsky's solutions for electromagnetic perturbations in Kerr spacetime, and the conservation laws imposed by the energy momentum tensor of the electromagnetic field and the Killing vectors of the spacetime, we prove that this interaction cannot convert the black hole into a naked singularity, thus cosmic censorship conjecture is not violated in this case.

Koray Dzta?

2014-04-09T23:59:59.000Z

16

IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 58, NO. 1, JANUARY 2009 129 Very-Low-Frequency Electromagnetic Field  

E-Print Network [OSTI]

, Walter J. Varhue, and Stephen Titcomb, Senior Member, IEEE Abstract--Naturally occurring electromagnetic and difficult to detect under normal conditions. These naturally occurring VLF electromagnetic events. This electronic system can be used to monitor VLF electromagnetic radiation in residential and occupational

Motai, Yuichi

17

Electromagnetic source localization with finite set of frequency measurements  

E-Print Network [OSTI]

A phase conjugation algorithm for localizing an extended radiating electromagnetic source from boundary measurements of the electric field is presented. Measurements are taken over a finite number of frequencies. The artifacts related to the finite frequency data are tackled with $l_1-$regularization blended with the fast iterative shrinkage-thresholding algorithm with backtracking of Beck & Teboulle.

Abdul Wahab; Amer Rasheed; Rab Nawaz; Saman Anjum

2014-09-16T23:59:59.000Z

18

STIMULATED ELECTROMAGNETIC EMISSIONS BY HIGH-FREQUENCY ELECTROMAGNETIC PUMPING OF THE  

E-Print Network [OSTI]

STIMULATED ELECTROMAGNETIC EMISSIONS BY HIGH-FREQUENCY ELECTROMAGNETIC PUMPING OF THE IONOSPHERIC.S.A. Abstract. A high frequency electromagnetic pump wave transmitted into the ionospheric plasma from the ground can stimulate electromagnetic radiation with frequencies around that of the ionospher- ically

19

High frequency (900MHz) low amplitude (5Vm?1) electromagnetic field: a genuine environmental stimulus that affects transcription, translation, calcium and energy charge in tomato  

Science Journals Connector (OSTI)

Using an especially-designed facility, the Mode Stirred Reverberation Chamber, we exposed tomato plants (Lycopersicon esculentum...Mill. VFN8) to low level (900MHz, 5Vm?1) electromagnetic fields for a short pe...

David Roux; Alain Vian; Sbastien Girard; Pierre Bonnet; Franoise Paladian

2008-03-01T23:59:59.000Z

20

Invisibility & Control of Electromagnetic fields  

E-Print Network [OSTI]

Invisibility & Control of Electromagnetic fields JB Pendry The Blackett Laboratory, Imperial to make something invisible Science 312 1780-2 (2006), JB Pendry, D Schurig, and DR Smith 1. define a region that is to be invisible 2. surround it with an optical medium that can bend light 3. design

van Tiggelen, Bart

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Modulation of redox status and calcium handling by extremely low frequency electromagnetic fields in C2C12 muscle cells: A real-time, single-cell approach  

Science Journals Connector (OSTI)

The biological effects of electric and magnetic fields, which are ubiquitous in modern society, remain poorly understood. Here, we applied a single-cell approach to study the effects of short-term exposure to extremely low frequency electromagnetic fields (ELF-EMFs) on muscle cell differentiation and function using C2C12 cells as an in vitro model of the skeletal muscle phenotype. Our focus was on markers of oxidative stress and calcium (Ca2+) handling, two interrelated cellular processes previously shown to be affected by such radiation in other cell models. Collectively, our data reveal that ELF-EMFs (1) induced reactive oxygen species production in myoblasts and myotubes with a concomitant decrease in mitochondrial membrane potential; (2) activated the cellular detoxification system, increasing catalase and glutathione peroxidase activities; and (3) altered intracellular Ca2+homeostasis, increasing the spontaneous activity of myotubes and enhancing cellular reactivity to a depolarizing agent (KCl) or an agonist (caffeine) of intracellular store Ca2+channels. In conclusion, our data support a possible link between exposure to ELF-EMFs and modification of the cellular redox state, which could, in turn, increase the level of intracellular Ca2+and thus modulate the metabolic activity of C2C12 cells.

Caterina Morabito; Francesca Rovetta; Mariano Bizzarri; Giovanna Mazzoleni; Giorgio Fan; Maria A. Mariggi

2010-01-01T23:59:59.000Z

22

Frequency spectrum analysis of electromagnetic waves radiated by electrical discharges  

Science Journals Connector (OSTI)

In this study, we analyzed the frequency spectrum of the electromagnetic waves radiated by an electric discharge as a basic method for developing an on-line diagnostic technique for power equipment installed inside closed-switchboards. In order to simulate ... Keywords: closed-switchboard, electromagnetic shielding room, electromagnetic wave, frequency spectrum, local discharge, series arc discharge

Hyeon-Kyu Cha; Sun-Jae Kim; Dae-Won Park; Gyung-Suk Kil

2011-03-01T23:59:59.000Z

23

Assessment of the neurotoxic potential of exposure to 50Hz extremely low frequency electromagnetic fields (ELF-EMF) in nave and chemically stressed PC12 cells  

Science Journals Connector (OSTI)

Abstract Increasing exposure to extremely low frequency electromagnetic fields (ELF-EMF), generated by power lines and electric appliances, raises concern about potential adverse health effects of ELF-EMF. The central nervous system is expected to be particularly vulnerable to ELF-EMF as its function strongly depends on electrical excitability. We therefore investigated effects of acute (30min) and sub-chronic (48h) exposure to 50Hz ELF-EMF on nave and chemically stressed pheochromocytoma (PC12) cells. The latter have higher levels of iron and/or reactive oxygen species (ROS) and display increased vulnerability to environmental insults. Effects of ELF-EMF on Ca2+-homeostasis, ROS production and membrane integrity were assessed using Fura-2 single cell fluorescence microscopy, H2-DCFDA and CFDA assays, respectively. Our data demonstrate that acute exposure of nave PC12 cells to 50Hz ELF-EMF up to 1000?T fails to affect basal or depolarization-evoked [Ca2+]i. Moreover, sub-chronic ELF-EMF exposure up to 1000?T has no consistent effects on Ca2+-homeostasis in nave PC12 cells and does not affect ROS production and membrane integrity. Notably, in chemically stressed PC12 cells both acute and sub-chronic ELF-EMF exposure also failed to exert consistent effects on Ca2+-homeostasis, ROS production and membrane integrity. Our combined findings thus indicate that exposure to 50Hz ELF-EMF up to 1000?T, i.e. 10,000 times above background exposure, does not induce neurotoxic effects in vitro, neither in nave nor in chemically stressed PC12 cells. Though our data require confirmation, e.g. in developing neuronal cells in vitro or (developing) animals, it appears that the neurotoxic risk of ELF-EMF exposure is limited.

Martje W.G.D.M. de Groot; Marjolijn D.M. Kock; Remco H.S. Westerink

2014-01-01T23:59:59.000Z

24

Electromagnetic field with constraints and Papapetrou equation  

E-Print Network [OSTI]

It is shown that geometric optical description of electromagnetic wave with account of its polarization in curved space-time can be obtained straightforwardly from the classical variational principle for electromagnetic field. For this end the entire functional space of electromagnetic fields must be reduced to its subspace of locally plane monochromatic waves. We have formulated the constraints under which the entire functional space of electromagnetic fields reduces to its subspace of locally plane monochromatic waves. These constraints introduce variables of another kind which specify a field of local frames associated to the wave and contain some congruence of null-curves. The Lagrangian for constrained electromagnetic field contains variables of two kinds, namely, a congruence of null-curves and the field itself. This yields two kinds of Euler-Lagrange equations. Equations of first kind are trivial due to the constraints imposed. Variation of the curves yields the Papapetrou equations for a classical massless particle with helicity 1.

Z. Ya. Turakulov; A. T. Muminov

2006-01-12T23:59:59.000Z

25

Resonant circuit which provides dual-frequency excitation for rapid cycling of an electromagnet  

DOE Patents [OSTI]

Disclosed is a novel ring-magnet control circuit that permits synchrotron repetition rates much higher than the frequency of the sinusoidal guide field of the ring magnet during particle acceleration. The control circuit generates sinusoidal excitation currents of different frequencies in the half waves. During radio-frequency acceleration of the synchrotron, the control circuit operates with a lower frequency sine wave and, thereafter, the electromagnets are reset with a higher-frequency half sine wave.

Praeg, W.F.

1982-03-09T23:59:59.000Z

26

Noninvasive valve monitor using alternating electromagnetic field  

DOE Patents [OSTI]

One or more electrical coils are carefully located on the outside of a valve body. An alternating current passing through the coil(s) results in an alternating electromagnetic field being transmitted into the valve body and valve internals. The electromagnetic field varies in intensity and polarity in the valve. As the position of a valve internal part is changed, the electromagnetic field throughout the valve body and its internals is altered. A passive receiver coil carefully located on the outside of the valve body detects the intensity of the electromagnetic field at that location as an induced electrical voltage in the coil. With the change in position of the valve internal part, there is a corresponding change in the induced voltage as a result of the alteration in the alternating electromagnetic field at that location. Changes in the voltage provide an indication of the position and motion of valve internals.

Eissenberg, David M. (Oak Ridge, TN); Haynes, Howard D. (Knoxville, TN); Casada, Donald A. (Knoxville, TN)

1993-01-01T23:59:59.000Z

27

Scattering by an electromagnetic radiation field  

E-Print Network [OSTI]

Motion of test particles in the gravitational field associated with an electromagnetic plane wave is investigated. The interaction with the radiation field is modeled by a force term {\\it \\`a la} Poynting-Robertson entering the equations of motion given by the 4-momentum density of radiation observed in the particle's rest frame with a multiplicative constant factor expressing the strength of the interaction itself. Explicit analytical solutions are obtained. Scattering of fields by the electromagnetic wave, i.e., scalar (spin 0), massless spin $\\frac12$ and electromagnetic (spin 1) fields, is studied too.

Donato Bini; Andrea Geralico

2014-08-21T23:59:59.000Z

28

Low Audio-frequency Electromagnetic Signals of Natural Origin  

Science Journals Connector (OSTI)

... a year ago, we undertook a programme of measurement of natural electromagnetic signals in the audio-frequency range 25-130 cycles/sec, with the view of gathering evidence concerning their ...

R. E. HOLZER; O. E. DEAL

1956-03-17T23:59:59.000Z

29

Gauge Fields, Sources, and Electromagnetic Masses  

Science Journals Connector (OSTI)

The hypothesis of strong-interaction gauge fields, with non-Abelian gauge invariance broken only by the 1- particle mass terms, gives a natural source theory setting for the introduction of electromagnetic effects. The electromagnetic potential vector appears as a compensating field in the mass terms of the neutral 1- particles. The resulting electromagnetic self-action is used to discuss mass displacements. The pion electro-magnetic mass is computed in a number of waysby direct calculation of various processes and by chiral methods, in two variants. The relationship of these approaches is established. A phenomenological modification of the chiral evaluation gives perfect agreement with the observed value. It is found, however, that the (m?m?)2 terms, which are neglected in this method, are not very small. Baryon electromagnetic mass splittings are described by a simple adaptation of gross mass-spectrum empirics. Agreement with the data is excellent.

Julian Schwinger

1968-01-25T23:59:59.000Z

30

Frequency-Domain Electromagnetic Survey | Open Energy Information  

Open Energy Info (EERE)

Frequency-Domain Electromagnetic Survey Frequency-Domain Electromagnetic Survey Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Frequency-Domain Electromagnetic Survey Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electromagnetic Profiling Techniques Information Provided by Technique Lithology: Detection of high-conductivity bodies in the subsurface. Stratigraphic/Structural: Hydrological: Thermal: Detection of the presence of a thermal anomaly through its resistivity signature. Cost Information Low-End Estimate (USD): 2,928.38292,838 centUSD 2.928 kUSD 0.00293 MUSD 2.92838e-6 TUSD / mile Median Estimate (USD): 4,505.20450,520 centUSD

31

Simulation and Modeling Techniques for Signal Integrity and Electromagnetic Interference on High Frequency Electronic Systems.  

E-Print Network [OSTI]

Simulation and Modeling Techniques for Signal Integrity and Electromagnetic Interference on High and Modeling Techniques for Signal Integrity and Electromagnetic Interference on High Frequency Electronic Integrity and Electromagnetic Interference on High Frequency Electronic Systems. by Luca Daniel Doctor

Daniel, Luca

32

Electromagnetic field with induced massive term: Case with scalar field  

E-Print Network [OSTI]

We consider an interacting system of massless scalar and electromagnetic field, with the Lagrangian explicitly depending on the electromagnetic potentials, i.e., interaction with broken gauge invariance. The Lagrangian for interaction is chosen in such a way that the electromagnetic field equation acquires an additional term, which in some cases is proportional to the vector potential of the electromagnetic field. This equation can be interpreted as the equation of motion of photon with induced nonzero rest-mass. This system of interacting fields is considered within the scope of Bianchi type-I (BI) cosmological model. It is shown that, as a result of interaction the electromagnetic field vanishes at $t \\to \\infty$ and the isotropization process of the expansion takes place.

Yu. P. Rybakov; G. N. Shikin; Yu. A. Popov; Bijan Saha

2010-04-21T23:59:59.000Z

33

Electromagnetic field with induced massive term: Case with spinor field  

E-Print Network [OSTI]

We consider an interacting system of spinor and electromagnetic field, explicitly depending on the electromagnetic potentials, i.e., interaction with broken gauge invariance. The Lagrangian for interaction is chosen in such a way that the electromagnetic field equation acquires an additional term, which in some cases is proportional to the vector potential of the electromagnetic field. This equation can be interpreted as the equation of motion of photon with induced non-trivial rest-mass. This system of interacting spinor and scalar fields is considered within the scope of Bianchi type-I (BI) cosmological model. It is shown that, as a result of interaction the electromagnetic field vanishes at $t \\to \\infty$ and the isotropization process of the expansion takes place.

Yu. P. Rybakov; G. N. Shikin; Yu. A. Popov; Bijan Saha

2010-08-12T23:59:59.000Z

34

Response of radio frequency superconducting quantum interference devices to electromagnetic interference  

SciTech Connect (OSTI)

A number of applications of high-temperature superconductor radio frequency superconducting quantum interference devices (rf SQUIDs) require a certain immunity of these sensors against electromagnetic interference (EMI). We have investigated effects of electromagnetic radiation in the high-frequency and ultrahigh-frequency range on various types of rf SQUIDs. It has been found that EMI of sufficient field strength reduces the voltage versus flux transfer function, and thus increases the flux noise of the SQUIDs. SQUIDs with a wire wound tank circuit coil have been found to be more sensitive to EMI than SQUIDs integrated into a superconducting microstrip resonator. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Mueck, M.; Dechert, J.; Gail, J.; Kreutzbruck, M.; Schoene, S.; Weidl, R. [Institut fuer Angewandte Physik, Justus-Liebig-Universitaet Giessen, Heinrich-Buff-Ring 16, 35392 Giessen (Germany)] [Institut fuer Angewandte Physik, Justus-Liebig-Universitaet Giessen, Heinrich-Buff-Ring 16, 35392 Giessen (Germany)

1995-09-01T23:59:59.000Z

35

Singular Modes of the Electromagnetic Field  

E-Print Network [OSTI]

We show that the mode corresponding to the point of essential spectrum of the electromagnetic scattering operator is a vector-valued distribution representing the square root of the three-dimensional Dirac's delta function. An explicit expression for this singular mode in terms of the Weyl sequence is provided and analyzed. An essential resonance thus leads to a perfect localization (confinement) of the electromagnetic field, which in practice, however, may result in complete absorption.

Neil V. Budko; Alexander B. Samokhin

2006-06-15T23:59:59.000Z

36

Singular Modes of the Electromagnetic Field  

E-Print Network [OSTI]

We show that the mode corresponding to the point of essential spectrum of the electromagnetic scattering operator is a vector-valued distribution representing the square root of the three-dimensional Dirac's delta function. An explicit expression for this singular mode in terms of the Weyl sequence is provided and analyzed. An essential resonance thus leads to a perfect localization (confinement) of the electromagnetic field, which in practice, however, may result in complete absorption.

Budko, N V; Budko, Neil V.; Samokhin, Alexander B.

2006-01-01T23:59:59.000Z

37

Hydrodynamic construction of the electromagnetic field  

E-Print Network [OSTI]

We present an alternative Eulerian hydrodynamic model for the electromagnetic field in which the discrete vector indices in Maxwell\\s equations are replaced by continuous angular freedoms, and develop the corresponding Lagrangian picture in which the fluid particles have rotational and translational freedoms. This enables us to extend to the electromagnetic field the exact method of state construction proposed previously for spin 0 systems, in which the time-dependent wavefunction is computed from a single-valued continuum of deterministic trajectories where two spacetime points are linked by at most a single orbit. The deduction of Maxwell\\s equations from continuum mechanics is achieved by generalizing the spin 0 theory to a general Riemannian manifold from which the electromagnetic construction is extracted as a special case. In particular, the flat-space Maxwell equations are represented as a curved-space Schr\\"odinger equation for a massive system. The Lorentz covariance of the Eulerian field theory is obtained from the non-covariant Lagrangian-coordinate model as a kind of collective effect. The method makes manifest the electromagnetic analogue of the quantum potential that is tacit in Maxwell\\s equations. This implies a novel definition of the \\classical limit\\ of Maxwell\\s equations that differs from geometrical optics. It is shown that Maxwell\\s equations may be obtained by canonical quantization of the classical model. Using the classical trajectories a novel expression is derived for the propagator of the electromagnetic field in the Eulerian picture. The trajectory and propagator methods of solution are illustrated for the case of a light wave.

Peter Holland

2014-10-03T23:59:59.000Z

38

Quantum states in rotating electromagnetic fields  

E-Print Network [OSTI]

We describe a new class of exact square integrable solutions of the Pauli and Dirac equation in rotating electromagnetic fields. Solutions obtained by putting equations in the stationary form with help of a coordinate transformation corresponding to the transition into a rotating frame. The transformation is assumed to be Galilean one however a non-Galilean transformation is of particular interest for such solutions. Obtained solutions, especially of Dirac's equation, are valid for arbitrary values of parameters and may be tested experimentally.

B. V. Gisin

2010-11-11T23:59:59.000Z

39

The effect of electromagnetic forces on the penetrator formation during high-frequency electric resistance welding  

Science Journals Connector (OSTI)

During high-frequency electric resistance welding (HF-ERW), the electromagnetic force induced by the high-frequency electric current was studied to improve the understanding of penetrator formation mechanism. ERW melting zone behavior is investigated by the cinematography and the three-dimensional numerical analysis of electromagnetic field around molten metal bridge. Based on the results, the penetrator formation is mainly influenced by the narrow gap shape, the variation of electromagnetic forces along the narrow gap, the molten metal bridge traveling speed, and the second bridge formation frequency. Electromagnetic force acting on the molten metal bridge is rapidly decreasing as the bridge is traveling away from the apex point. The comet shape narrow gap produced by the variation of Lorentz forces makes the bridge pushing pressure decrease. Due to the decrease of electromagnetic force and pushing pressure, the sweeping speed of molten metal bridge slows down until the bridge reaches the welding point. Previous molten metal bridge traveling is arrested when the next bridge is formed before the previous bridge arrives at the welding point. Thus, the molten metal and oxide are refilled into the narrow gap due to the capillary force and then remained as a penetrator. According to the analysis of penetrator formation mechanism, the new penetrator formation model is proposed.

Choong-Myeong Kim; Jung-Kyu Kim

2009-01-01T23:59:59.000Z

40

Quantum Mechanics Action of ELF Electromagnetic Fields on Living Organisms  

Science Journals Connector (OSTI)

There is presently an intense discussion if extremely low frequency electromagnetic field (ELF?EMF) exposure has consequences for human health. This include exposure to structures and appliances from this range of frequency in the electromagnetic (EM) spectrum. Biological effects of such exposures have been noted frequently although the implications for specific health effects is not that clear. The basic interactions mechanisms between such fields and living matter is unknown. Numerous hypotheses have been suggested although none is convincingly supported by experimental data. Various cellular components processes and systems can be affected by EMF exposure. Since it is unlikely that EMF can induce DNA damage directly most studies have examined EMF effects on the cell membrane level general and specific gene expression and signal transduction pathways. Even more a large number of studies have been performed regarding cell proliferation cell cycle regulation cell differentiation metabolism and various physiological characteristics of cells. The aim of this letter is present the hypothesis of a possible quantum mechanic effect generated by the exposure of ELF EMF an event which is compatible with the multitude of effects observed after exposure. Based on an extensive literature review we suggest that ELF EMF exposure is able to perform such activation restructuring the electronic level of occupancy of free radicals in molecules interacting with DNA structures.

J. J. Godina?Nava

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Frequency-domain multiscale quantum mechanics/electromagnetics simulation method  

SciTech Connect (OSTI)

A frequency-domain quantum mechanics and electromagnetics (QM/EM) method is developed. Compared with the time-domain QM/EM method [Meng et al., J. Chem. Theory Comput. 8, 11901199 (2012)], the newly developed frequency-domain QM/EM method could effectively capture the dynamic properties of electronic devices over a broader range of operating frequencies. The system is divided into QM and EM regions and solved in a self-consistent manner via updating the boundary conditions at the QM and EM interface. The calculated potential distributions and current densities at the interface are taken as the boundary conditions for the QM and EM calculations, respectively, which facilitate the information exchange between the QM and EM calculations and ensure that the potential, charge, and current distributions are continuous across the QM/EM interface. Via Fourier transformation, the dynamic admittance calculated from the time-domain and frequency-domain QM/EM methods is compared for a carbon nanotube based molecular device.

Meng, Lingyi; Yin, Zhenyu; Yam, ChiYung, E-mail: yamcy@yangtze.hku.hk, E-mail: ghc@everest.hku.hk; Koo, SiuKong; Chen, GuanHua, E-mail: yamcy@yangtze.hku.hk, E-mail: ghc@everest.hku.hk [Department of Chemistry, The University of Hong Kong, Pokfulam Road (Hong Kong)] [Department of Chemistry, The University of Hong Kong, Pokfulam Road (Hong Kong); Chen, Quan; Wong, Ngai [Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road (Hong Kong)] [Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road (Hong Kong)

2013-12-28T23:59:59.000Z

42

Three-Dimensional Electromagnetic High Frequency Axisymmetric Cavity Scars.  

SciTech Connect (OSTI)

This report examines the localization of high frequency electromagnetic fi elds in three-dimensional axisymmetric cavities along periodic paths between opposing sides of the cavity. The cases where these orbits lead to unstable localized modes are known as scars. This report treats both the case where the opposing sides, or mirrors, are convex, where there are no interior foci, and the case where they are concave, leading to interior foci. The scalar problem is treated fi rst but the approximations required to treat the vector fi eld components are also examined. Particular att ention is focused on the normalization through the electromagnetic energy theorem. Both projections of the fi eld along the scarred orbit as well as point statistics are examined. Statistical comparisons are m ade with a numerical calculation of the scars run with an axisymmetric simulation. This axisymmetric cas eformstheoppositeextreme(wherethetwomirror radii at each end of the ray orbit are equal) from the two -dimensional solution examined previously (where one mirror radius is vastly di ff erent from the other). The enhancement of the fi eldontheorbitaxiscanbe larger here than in the two-dimensional case. Intentionally Left Blank

Warne, Larry K.; Jorgenson, Roy E.

2014-10-01T23:59:59.000Z

43

Electromagnetic field at Finite Temperature: A first order approach  

E-Print Network [OSTI]

In this work we study the electromagnetic field at Finite Temperature via the massless DKP formalism. The constraint analysis is performed and the partition function for the theory is constructed and computed. When it is specialized to the spin 1 sector we obtain the well-known result for the thermodynamic equilibrium of the electromagnetic field.

R. Casana; B. M. Pimentel; J. S. Valverde

2007-02-04T23:59:59.000Z

44

Characterization of microstructure with low frequency electromagnetic techniques  

SciTech Connect (OSTI)

A new computational method for characterizing the relationship between surface crystallography and electrical conductivity in anisotropic materials with low frequency electromagnetic techniques is presented. The method is discussed from the standpoint of characterizing the orientation of a single grain, as well as characterizing statistical information about grain ensembles in the microstructure. Large-area electron backscatter diffraction (EBSD) data was obtained and used in conjunction with a synthetic aperture approach to simulate the eddy current response of beta annealed Ti-6Al-4V. Experimental eddy current results are compared to the computed eddy current approximations based on electron backscatter diffraction (EBSD) data, demonstrating good agreement. The detectability of notches in the presence of noise from microstructure is analyzed with the described simulation method and advantages and limitations of this method are discussed relative to other NDE techniques for such analysis.

Cherry, Matthew R.; Sathish, Shamachary [University of Dayton Research Institute, Structural Integrity Division, 300 College Park, Dayton, OH 45469-0020 (United States); Pilchak, Adam L.; Blodgett, Mark P. [Air Force Research Laboratory, Materials and Manufacturing Directorate (AFRL/RXCM), 2230 10th St., WPAFB, OH 45433 (United States); Cherry, Aaron J. [Southwest Ohio Council for Higher Education, 3155 Research Blvd., Suite 204, Dayton, OH 45420-4015 (United States)

2014-02-18T23:59:59.000Z

45

Childhood leukemia and electromagnetic fields: results of a population-based case-control study in Germany  

Science Journals Connector (OSTI)

The investigation of an association between increased exposure toresidential extremely-low frequency elec-tromagnetic fields (ELF-EMF) andchildhood leukemia was part of a population-based case-control study ca...

Jrg Michaelis; Joachim Schz; Rolf Meinert; Michael Menger

1997-01-01T23:59:59.000Z

46

Lines of Circular Polarization in Electromagnetic Wave Fields  

Science Journals Connector (OSTI)

8 October 1983 research-article Lines of Circular Polarization in Electromagnetic Wave Fields J...free space possesses, in general, two families of singular lines ( lines) on which the transverse field is circularly polarized. The...

1983-01-01T23:59:59.000Z

47

A narrow window of Rabi frequency for competition between electromagnetically induced transparency and Raman absorption  

SciTech Connect (OSTI)

This investigation clarifies the transition phenomenon between the electromagnetically induced transparency (EIT) and Raman absorption in a ladder-type system of Doppler-broadened cesium vapor. A competition window of this transition was found to be as narrow as 2 MHz defined by the probe Rabi frequency. For a weak probe, the spectrum of EIT associated with quantum interference suggests that the effect of the Doppler velocity on the spectrum is negligible. When the Rabi frequency of the probe becomes comparable with the effective decay rate, an electromagnetically induced absorption (EIA) dip emerges at the center of the power broadened EIT peak. While the Rabi frequency of the probe exceeds the effective decay rate, decoherence that is generated by the intensified probe field occurs and Raman absorption dominates the interaction process, yielding a pure absorption spectrum; the Doppler velocity plays an important role in the interaction. A theory that is based on density matrix simulation, with or without the Doppler effect, can qualitatively fit the experimental data. In this work, the coherence of atom-photon interactions is created or destroyed using the probe Rabi frequency as a decoherence source.

Chang, Ray-Yuan; Fang, Wei-Chia; Lee, Ming-Tsung; He, Zong-Syun; Ke, Bai-Cian [Department of Physics, National Cheng-Kung University, Tainan 70101, Taiwan (China); Lee, Yi-Chi [Institute of Electro-Optical Science and Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China); Tsai, Chin-Chun [Department of Physics, National Cheng-Kung University, Tainan 70101, Taiwan (China); Institute of Electro-Optical Science and Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China)

2010-01-15T23:59:59.000Z

48

Electromagnetic Field Creation During EWPT Nucleation With Lepton Currents  

E-Print Network [OSTI]

We include the electromagnetic currents from fermion degrees of freedom in the equations of motion for electroweak MSSM with a right-handed Stop that we have recently investigated. It is found that near the surface of the bubble walls there are important effects on the electromagnetic fields produced during bubble nucleation.

Leonard S. Kisslinger; Sameer Walawalkar; Ernest M. Henley; Mikkel B. Johnson

2005-10-11T23:59:59.000Z

49

E-Print Network 3.0 - ac electromagnetic field Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Topics (time permitting). 12;The Nature of Electromagnetism Electric and magnetic fields... that are coupled; they are then referred to as an electromagnetic field....

50

Binary high-frequency-carrier diffractive optical elements: electromagnetic theory  

Science Journals Connector (OSTI)

Using rigorous electromagnetic diffraction theory, we evaluate the potential performance and the limitations of coding diffractive optical elements in the form of a...

Noponen, Eero; Turunen, Jari

1994-01-01T23:59:59.000Z

51

Effects of Electromagnetic Fields on Fish and Invertebrates  

SciTech Connect (OSTI)

In this progress report, we describe the preliminary experiments conducted with three fish and one invertebrate species to determine the effects of exposure to electromagnetic fields. During fiscal year 2010, experiments were conducted with coho salmon (Onchrohychus kisutch), California halibut (Paralicthys californicus), Atlantic halibut (Hippoglossus hippoglossus), and Dungeness crab (Cancer magister). The work described supports Task 2.1.3: Effects on Aquatic Organisms, Subtask 2.1.3.1: Electromagnetic Fields.

Schultz, Irvin R.; Woodruff, Dana L.; Marshall, Kathryn E.; Pratt, William J.; Roesijadi, Guritno

2010-10-13T23:59:59.000Z

52

Excitation and propagation of electromagnetic fluctuations with ion-cyclotron range of frequency in magnetic reconnection laboratory experiment  

SciTech Connect (OSTI)

Large-amplitude electromagnetic fluctuations of ion-cyclotron-frequency range are detected in a laboratory experiment inside the diffusion region of a magnetic reconnection with a guide field. The fluctuations have properties similar to kinetic Alfvn waves propagating obliquely to the guide field. Temporary enhancement of the reconnection rate is observed during the occurrence of the fluctuations, suggesting a relationship between the modification in the local magnetic structure given by these fluctuations and the intermittent fast magnetic reconnection.

Inomoto, Michiaki; Tanabe, Hiroshi; Ono, Yasushi [Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)] [Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Kuwahata, Akihiro [Graduate School of Engineering, The University of Tokyo,7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan)] [Graduate School of Engineering, The University of Tokyo,7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Collaboration: TS Group

2013-06-15T23:59:59.000Z

53

Magnetic field effect on stimulated Raman scattering of electromagnetic waves from nanoparticle lattice  

SciTech Connect (OSTI)

The influence of a static magnetic field on the Raman scattering of a millimeter pump wave propagating through periodic nanoparticles is studied. Formulas for the growth rate of the scattered electromagnetic wave and the electrostatic wave are derived and analyzed. It is found that the growth rate for the backscattering case is larger than that of forward scattering and the growth rate is increased by the static magnetic field. A resonance in the dispersion relation of the electromagnetic wave is found as a combination of the cyclotron and plasma frequency. However, no instability was found for this lower branch of the dispersion curve.

Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2011-02-15T23:59:59.000Z

54

Electromagnetic field of a charge intersecting a cold plasma boundary in a waveguide  

SciTech Connect (OSTI)

We analyze the electromagnetic field of a charge crossing a boundary between a vacuum and cold plasma in a waveguide. We obtain exact expressions for the field components and the spectral density of the transition radiation. With the steepest descent technique, we investigate the field components. We show that the electromagnetic field has a different structure in a vacuum than in cold plasma. We also develop an algorithm for the computation of the field based on a certain transformation of the integration path. The behavior of the field depending on distance and time and the spectral density depending on frequency are explored for different charge velocities. Some important physical effects are noted. A considerable increase and concentration of the field near the wave front in the plasma is observed for the case of ultrarelativistic particles. In the plasma, the mode envelopes and spectral density show zero points when the charge velocity is within certain limits.

Alekhina, Tatiana Yu.; Tyukhtin, Andrey V. [Radiophysics Department of St. Petersburg University, 1 Ulyanovskaya, St. Petersburg 198504 (Russian Federation)

2011-06-15T23:59:59.000Z

55

An investigation of the usefulness of extremely low-frequency electromagnetic measurements for treaty verification  

SciTech Connect (OSTI)

From FY 1986 through FY 1988, we monitored extremely low-frequency (ELF) electromagnetic (EM) fields to determine whether these signals could be detected from underground nuclear explosions. Signals clearly related to underground tests were detected only when the ELF field sensors were located within 10 km of surface ground zero. Theoretical analysis, based on the results of these measurements, shows that the ELF impulse signals from underground nuclear tests are of longer duration than those from lightning sources and are, therefore, less efficient in exciting resonances in the earth-ionosphere cavity, even though the source strength for each may be the same. Thus, ELF signals from underground nuclear tests with yields of <150 kT are generally lower than the background signals caused by worldwide lightning activity. Our conclusion is that ELF monitoring probably will not be useful for detecting underground nuclear tests at distances >10 km from the tests. 16 refs., 24 figs., 3 tabs.

Sweeney, J.J.

1989-01-01T23:59:59.000Z

56

Coherence Momentum in Second-Order Vectorial Coherence Theory of Stationary Electromagnetic Fields  

Science Journals Connector (OSTI)

In analog to the electromagnetic momentum, we introduce vector and tensor densities to the general coherence theory of vector electromagnetic fields, and present new conservation...

Wang, Wei; Takeda, Mitsuo

57

Coherence Momentum in Second-Order Vectorial Coherence Theory of Stationary Electromagnetic Fields  

Science Journals Connector (OSTI)

In analog to the electromagnetic momentum, we introduce vector and tensor densities to the general coherence theory of vector electromagnetic fields, and present new conservation laws...

Wang, Wei; Takeda, Mitsuo

58

Electromagnetic Field Quantization in Time-Dependent Dielectric Media  

E-Print Network [OSTI]

We present a Gupta-Bleuler quantization scheme for the electromagnetic field in time-dependent dielectric media. Starting from the Maxwell equations, a generalization of the Lorentz gauge condition adapted to time varying dielectrics is derived. Using this gauge, a Gupta-Bleuler approach to quantize all polarizations of the radiation field and the corresponding constraint condition are introduced. This new approach is different from the quantized electromagnetic field in vacuum in the sense that here the contributions of unphysical photons cannot be thoroughly eliminated, which further lead to a surface charge density. Finally, a discussion of potential experimental tests and possible implication is also made.

Xiao-Min Bei; Zhong-Zhu Liu

2011-04-18T23:59:59.000Z

59

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

SciTech Connect (OSTI)

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.

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)

2013-01-15T23:59:59.000Z

60

High frequency rectenna  

DOE Patents [OSTI]

The invention provides an inexpensive array of rectifying antennas which employ field emission diodes for rectifying electromagnetic waves of microwave frequencies and higher frequencies.

Logan, B. Grant (Danville, CA); Orvis, William J. (Livermore, CA)

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Lattice p-Form Electromagnetism and Chain Field Theory  

E-Print Network [OSTI]

Since Wilson's work on lattice gauge theory in the 1970s, discrete versions of field theories have played a vital role in fundamental physics. But there is recent interest in certain higher dimensional analogues of gauge theory, such as p-form electromagnetism, including the Kalb-Ramond field in string theory, and its nonabelian generalizations. It is desirable to discretize such `higher gauge theories' in a way analogous to lattice gauge theory, but with the fundamental geometric structures in the discretization boosted in dimension. As a step toward studying discrete versions of more general higher gauge theories, we consider the case of p-form electromagnetism. We show that discrete p-form electromagnetism admits a simple algebraic description in terms of chain complexes of abelian groups. Moreover, the model allows discrete spacetimes with quite general geometry, in contrast to the regular cubical lattices usually associated with lattice gauge theory. After constructing a suitable model of discrete spacetime for p-form electromagnetism, we quantize the theory using the Euclidean path integral formalism. The main result is a description of p-form electromagnetism as a `chain field theory' -- a theory analogous to topological quantum field theory, but with chain complexes replacing manifolds. This, in particular, gives a notion of time evolution from one `spacelike slice' of discrete spacetime to another.

Derek K. Wise

2005-10-08T23:59:59.000Z

62

A Continuous Field Theory of Matter and Electromagnetism  

E-Print Network [OSTI]

A continuous field theory of matter and electromagnetism is developed. The starting point of the theory is the classical Maxwell equations which are directly tied to the Riemann-Christoffel curvature tensor. This is done through the derivatives of the Maxwell tensor which are equated to a vector field contracted with the curvature tensor. The electromagnetic portion of the theory is shown to be equivalent to the classical Maxwell equations with the addition of a hidden variable. Because the proposed equations describing electromagnetism and matter differ from the classical Maxwell-Einstein equations, their ability to describe classical physics is shown for several situations by direct calculation. The inclusion of antimatter and the possibility of particle-like solutions exhibiting both quantized charge and mass are discussed.

Raymond J. Beach

2012-08-31T23:59:59.000Z

63

The Norwegian Public's Perception of Risk from Electromagnetic Fields  

Science Journals Connector (OSTI)

......public is concerned about the health effects of electromagnetic...3 of the population regard health effects as a likely consequence...consider the fields to be more dangerous than they formerly believed...particularly prominent. Women regard health effects more probable, and......

M.B. Maerli

1996-12-01T23:59:59.000Z

64

Electromagnetically induced transparency with quantized fields in optocavity mechanics  

SciTech Connect (OSTI)

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.

Huang Sumei; Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2011-04-15T23:59:59.000Z

65

Electromagnetic field quantization in a linear dielectric medium  

E-Print Network [OSTI]

By modeling a dielectric medium with two independent reservoirs, i.e., electric and magnetic reservoirs, the electromagnetic field is quantized in a linear dielectric medium consistently. A Hamiltonian is proposed from which using the Heisenberg equations, not only the Maxwell equations but also the structural equations can be obtained. Using the Laplace transformation, the wave equation for the electromagnetic vector potential is solved in the case of a homogeneous dielectric medium. Some examples are considered showing the applicability of the model to both absorptive and nonabsorptive dielectrics.

F. Kheirandish; M. Amooshahi

2005-11-13T23:59:59.000Z

66

Plasma Paramagnetism in Radio-Frequency Fields  

Science Journals Connector (OSTI)

A study by experiment, simulation, and theory has found that a plasma responds paramagnetically to the external rf magnetic field applied perpendicular to the static magnetic field with frequency ?frequency. This effect can be exploited in the rf plugging and heating of plasmas; it explains the earlier rf plugging experiment (type-3 coil) of Watari et al. at Nagoya and possibly the rf heating experiment of Dikii et al. on the Uragan stellarator.

Y. Ohsawa; M. Inutake; T. Tajima; T. Hatori; T. Kamimura

1979-10-22T23:59:59.000Z

67

Markov states of the quantum electromagnetic field  

Science Journals Connector (OSTI)

A translation-invariant state (a quantum Markov chain) is associated with a nearest-neighbor interaction on a one-dimensional lattice by a new technique which provides closed forms for all the correlation functions. When applied to an Ising-type perturbation of a chain of harmonic oscillators, the dynamics can be computed explicitly. The resulting translation-invariant distribution is substantially different from the Planck distribution when the temperature and the coupling constant are large. For the evolution of the field operators on a given mode, we obtain a natural nonlinear generalization of the theorem which states that the free evolution of the field operators is obtained by second quantization of the classical free evolution.

Luigi Accardi and Geoffrey S. Watson

1987-02-01T23:59:59.000Z

68

A stable frequency comb directly referenced to rubidium electromagnetically induced transparency and two-photon transitions  

SciTech Connect (OSTI)

We demonstrate an approach to create a stable erbium-fiber-based frequency comb at communication band by directly locking the combs to two rubidium atomic transitions resonances (electromagnetically induced transparency absorption and two-photon absorption), respectively. This approach directly transfers the precision and stability of the atomic transitions to the comb. With its distinguishing feature of compactness by removing the conventional octave-spanning spectrum and f-to-2f beating facilities and the ability to directly control the comb's frequency at the atomic transition frequency, this stable optical comb can be widely used in optical communication, frequency standard, and optical spectroscopy and microscopy.

Hou, Dong; Wu, Jiutao; Zhang, Shuangyou; Ren, Quansheng; Zhang, Zhigang; Zhao, Jianye, E-mail: zhaojianye@pku.edu.cn [Department of Electronics, Peking University, Beijing, 100871 (China)

2014-03-17T23:59:59.000Z

69

PARTICLE FILTER BASED MULTI-SENSOR FUSION FOR SOLVING LOW FREQUENCY ELECTROMAGNETIC NDE INVERSE PROBLEMS  

E-Print Network [OSTI]

PARTICLE FILTER BASED MULTI-SENSOR FUSION FOR SOLVING LOW FREQUENCY ELECTROMAGNETIC NDE INVERSE 48824 khantari,sdass@msu.edu, r.pradeep@ieee.org Abstract: Flaw profile characterization from NDE from multi-sensor data is considered. The NDE inverse problem is posed as a statistical inverse problem

Dass, Sarat C.

70

Ultrarelativistic electron states in a general background electromagnetic field  

E-Print Network [OSTI]

The feasibility of obtaining exact analytical results in the realm of QED in the presence of a background electromagnetic field is almost exclusively limited to a few tractable cases, where the Dirac equation in the corresponding background field can be solved analytically. This circumstance has restricted, in particular, the theoretical analysis of QED processes in intense laser fields to within the plane-wave approximation even at those high intensities, achievable experimentally only by tightly focusing the laser energy in space. Here, within the Wentzel-Kramers-Brillouin (WKB) or eikonal approximation, we construct analytically single-particle electron states in the presence of a background electromagnetic field of general space-time structure in the realistic assumption that the initial energy of the electron is the largest dynamical energy scale in the problem. The relatively compact expression of these states opens, in particular, the possibility of investigating analytically strong-field QED processes in the presence of spatially focused laser beams, which is of particular relevance in view of the upcoming experimental campaigns in this field.

A. Di Piazza

2014-07-27T23:59:59.000Z

71

Propagation of terahertz electromagnetic wave in plasma with inhomogeneous collision frequency  

SciTech Connect (OSTI)

In this paper, we investigate the absorption spectra of terahertz electromagnetic wave in plasma with inhomogeneous collision frequency. Profiles are introduced to describe the non-uniformity of collision frequency. It is interesting to find that when the plasma is collision frequency inhomogeneous, the absorption spectrum would decreases faster than that in uniform plasma. And the rate of decreasing would be different when the profile changes. Two parameters are set up to predict how the profiles affect the absorption spectra. Furthermore, the effects of electron density are also considered.

Tian, Yuan; Han, YiPing; Ling, YingJie [School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071 (China)] [School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071 (China); Ai, Xia [National Laboratory of Science and Technology on Antennas and Microwaves Xidian University, Xi'an 710071 (China)] [National Laboratory of Science and Technology on Antennas and Microwaves Xidian University, Xi'an 710071 (China)

2014-02-15T23:59:59.000Z

72

Electromagnetic waves reflection, transmission and absorption by graphene - magnetic semiconductor - graphene sandwich-structure in magnetic field: Faraday geometry  

E-Print Network [OSTI]

Electrodynamic properties of the graphene - magnetic semiconductor - graphene sandwich-structure have been investigated theoretically with taking into account the dissipation processes. Influence of graphene layers on electromagnetic waves propagation in graphene - semi-infinte magnetic semiconductor and graphene - magnetic semiconductor - graphene sandwich-structure has been analyzed. Frequency and field dependences of the reflectance, transmittance and absorbtance of electromagnetic waves by such structure have been calculated. The size effects associated with the thickness of the structure have been analyzed. The possibility of efficient control of electrodynamic properties of graphene - magnetic semiconductor - graphene sandwich structure by an external magnetic field has been shown.

Kuzmin, Dmitry A; Shavrov, Vladimir G

2014-01-01T23:59:59.000Z

73

Measurement and analysis of electromagnetic fields from trams, trains and hybrid cars  

Science Journals Connector (OSTI)

......optical radiation and electric and magnetic fields...Electromagnetic Fields in Automobiles (1996) Goteborg...study, measurements of electric and magnetic fields...few of the measured electric and magnetic field strengths...Non-U.S. Gov't | Automobiles Electromagnetic Fields......

Malka N. Halgamuge; Chathurika D. Abeyrathne; Priyan Mendis

2010-10-01T23:59:59.000Z

74

A field test of electromagnetic geophysical techniques for locating simulated in situ mining leach solution  

SciTech Connect (OSTI)

The US Bureau of Mines, The University of Arizona, Sandia National Laboratories, and Zonge Engineering and Research Organization, Inc., conducted cooperative field tests of six electromagnetic (EM) geophysical methods to compare their effectiveness in locating a brine solution simulating in situ leach solution or a high-conductivity plume of contamination. The brine was approximately 160 m below the surface. The testsite was the University's San Xavier experimental mine near Tucson, AZ. Geophysical surveys using surface and surface-borehole, time-domain electromagnetic (TEM) induction; surface controlled-source audiofrequency magnetotellurics (CSAMT); surface-borehole, frequency-domain electromagnetic (FEM) induction; crosshole FEM; and surface magnetic field ellipticity were conducted before and during brine injection. The surface TEM data showed a broad decrease in resistivity. CSAMT measurements with the conventional orientation did not detect the brine, but measurements with another orientation indicated some decrease in resistivity. The surface-borehole and crosshole methods located a known fracture and other fracture zones inferred from borehole induction logs. Surface magnetic field ellipticity data showed a broad decrease in resistivity at depth following brine injection.

Tweeton, D.R.; Hanson, J.C.; Friedel, M.J.; Sternberg, B.K.; Dahl, L.J.

1994-01-01T23:59:59.000Z

75

Essential state of the electromagnetic field and the double-slit experiment  

E-Print Network [OSTI]

A new class of generalized solutions related to the essential spectrum of linear Maxwell's equations is presented. The essential modes are given in terms of normalized singular Weyl's sequences, whose square represents Dirac's delta functions in spatial and angular frequency domains. The action integral associated with essential modes is well-defined. We claim that these modes represent the collapsed state of the electromagnetic field and, with some additional assumptions on the conservation of action, are suitable for describing the double-slit experiment in accordance with the orthodox point of view.

Budko, N V; Budko, Neil V.; Samokhin, Alexander B.

2006-01-01T23:59:59.000Z

76

Essential state of the electromagnetic field and the double-slit experiment  

E-Print Network [OSTI]

A new class of generalized solutions related to the essential spectrum of linear Maxwell's equations is presented. The essential modes are given in terms of normalized singular Weyl's sequences, whose square represents Dirac's delta functions in spatial and angular frequency domains. The action integral associated with essential modes is well-defined. We claim that these modes represent the collapsed state of the electromagnetic field and, with some additional assumptions on the conservation of action, are suitable for describing the double-slit experiment in accordance with the orthodox point of view.

Neil V. Budko; Alexander B. Samokhin

2006-10-02T23:59:59.000Z

77

Variational Principles for Constrained Electromagnetic Field and Papapetrou Equation  

E-Print Network [OSTI]

In our previous article [4] an approach to derive Papapetrou equations for constrained electromagnetic field was demonstrated by use of field variational principles. The aim of current work is to present more universal technique of deduction of the equations which could be applied to another types of non-scalar fields. It is based on Noether theorem formulated in terms of Cartan' formalism of orthonormal frames. Under infinitesimal coordinate transformation the one leads to equation which includes volume force of spin-gravitational interaction. Papapetrou equation for vector of propagation of the wave is derived on base of the equation. Such manner of deduction allows to formulate more accurately the constraints and clarify equations for the potential and for spin.

A. T. Muminov

2007-06-28T23:59:59.000Z

78

On the imaging of radio-frequency electromagnetic data forcross-borehole mineral exploration  

Science Journals Connector (OSTI)

......the subsurface. borehole|electromagnetic...determine future drilling or excavation targets...the Chinese JW-4 borehole electric-field...targets are rare. The large conductivity contrast...the transmitter borehole (Fig. 12). The...separations much larger than a characteristic......

L. Yu; M. Chouteau; D. E. Boerner; J. Wang

1998-11-01T23:59:59.000Z

79

Electromagnetic Field in de Sitter Expanding Universe: Majorana--Oppenheimer Formalism, Exact Solutions in non-Static Coordinates  

E-Print Network [OSTI]

Tetrad-based generalized complex formalism by Majorana--Oppenheimer is applied to treat electromagnetic field in extending de Sitter Universe in on-static spherically-symmetric coordinates. With the help of Wigner D-functions, we separate angular dependence in the complex vector field E_{j}(t,r)+i B_{j}(t,r) from (t,r)-dependence. The separation parameter arising here instead of frequency \\omega in Minkowski space-time is quantized, non-static geometry of the de Sitter model leads to definite dependence of electromagnetic modes on the time variable. Relation of 3-vector complex approach to 10-dimensional Duffin-Kemmer-Petiau formalism is considered. On this base, the electromagnetic waves of magnetic and electric type have been constructed in both approaches. In Duffin-Kemmer-Petiau approach, there are constructed gradient-type solutions in Lorentz gauge.

O. V. Veko; N. D Vlasii; Yu. A. Sitenko; E. M. Ovsiyuk; V. M. Red'kov

2014-10-30T23:59:59.000Z

80

Electromagnetic Field in de Sitter Expanding Universe: Majorana--Oppenheimer Formalism, Exact Solutions in non-Static Coordinates  

E-Print Network [OSTI]

Tetrad-based generalized complex formalism by Majorana--Oppenheimer is applied to treat electromagnetic field in extending de Sitter Universe in on-static spherically-symmetric coordinates. With the help of Wigner D-functions, we separate angular dependence in the complex vector field E_{j}(t,r)+i B_{j}(t,r) from (t,r)-dependence. The separation parameter arising here instead of frequency \\omega in Minkowski space-time is quantized, non-static geometry of the de Sitter model leads to definite dependence of electromagnetic modes on the time variable. Relation of 3-vector complex approach to 10-dimensional Duffin-Kemmer-Petiau formalism is considered. On this base, the electromagnetic waves of magnetic and electric type have been constructed in both approaches. In Duffin-Kemmer-Petiau approach, there are constructed gradient-type solutions in Lorentz gauge.

Veko, O V; Sitenko, Yu A; Ovsiyuk, E M; Red'kov, V M

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Electromagnetic field optimization for enhancing photovoltaic efficiency of organic solar cells  

Science Journals Connector (OSTI)

The electromagnetic field distribution inside multilayer organic solar cells composed of interpenetrated networks of conjugated polymers is calculated. By enhancing the...

Simon, Jean-Jacques; Torchio, Philippe; Escoubas, Ludovic; Cathelinaud, Michel; Alem, Salima; Nunzi, Jean-Michel

82

Quantum Energy Teleportation with Electromagnetic Field: Discrete vs. Continuous Variables  

E-Print Network [OSTI]

Local measurements of quantum fluctuation in the vacuum state of electromagnetic field require energy infusion to the field. The infused energy is diffused to spatial infinity with light velocity and the state of the field soon becomes a local vacuum with zero energy around the measurement area. Of cource we cannot retrieve energy from this measurement area if we do not know the measurement result of the fluctuation. However, if the measurement result is available for us, we are able to extract energy from the local vacuum of the field, applying the protocol of quantum energy teleportation recently proposed. By performing a local unitary operation around the measurement area dependent on the measurement result, the fluctuaion of zero-point oscillation is squeezed and negative energy density appears around the area, accompanied by extraction of positive energy from the field. In this paper, we compare two different protocols of the energy retrieval. In the first protocol, a 1/2 spin is coupled with the fluctua...

Hotta, Masahiro

2009-01-01T23:59:59.000Z

83

On the gravitational fields created by the electromagnetic waves  

E-Print Network [OSTI]

We show that the Maxwell equations describing an electromagnetic wave are a mathematical consequence of the Einstein equations for the same wave. This fact is significant for the problem of the Einsteinian metrics corresponding to the electromagnetic waves.

A. Loinger; T. Marsico

2011-06-11T23:59:59.000Z

84

Paternal occupational exposure to electromagnetic fields and neuroblastoma in offspring  

SciTech Connect (OSTI)

Investigators in Texas have reported an association between paternal employment in jobs linked with exposure to electromagnetic fields and risk of neuroblastoma in offspring. In an attempt to replicate this finding, the authors conducted a case-control study in Ohio. A total of 101 incident cases of neuroblastoma were identified through the Columbus (Ohio) Children's Hospital Tumor Registry. All cases were born sometime during the period 1942-1967. From a statewide roster of birth certificates, four controls were selected for each case, with individual matching on the case's year of birth, race, and sex, and the mother's county of residence at the time of the (index) child's birth. Multiple definitions were employed to infer the potential for paternal occupational exposure to electromagnetic fields from the industry/occupation statements on the birth certificates. Case-control comparisons revealed adjusted odds ratios ranging in magnitude from 0.5 to 1.9. For two of the exposure definitions employed--both of which are similar to one used by the Texas investigators--the corresponding odds ratios were modestly elevated (odds ratios = 1.6 and 1.9). Notably, the magnitude of these odds ratios is not inconsistent with the Texas findings, where the exposure definition referred to yielded an odds ratio of 2.1. Because the point estimates in this study are imprecise, and because the biologic plausibility of the association is uncertain, the results reported here must be interpreted cautiously. However, the apparent consistency between two independent studies suggests that future evaluation of the association is warranted.

Wilkins, J.R. 3d.; Hundley, V.D. (Ohio State Univ., Columbus (USA))

1990-06-01T23:59:59.000Z

85

Radio-Frequency and ELF Electromagnetic Energies: A handbook for health professionals  

Science Journals Connector (OSTI)

...the areas that are most objective. The important introductory chapter on general concepts is naive and confused. Simple, fundamental matters, such as the part of the Lorentz force law that pertains to magnetic fields, are mishandled, and the section called "Free-Space Impedance" is bizarre. Weaknesses... We live in a sea of electromagnetic fields. But the sea is shallow, and the fields are so minute that they are detectable only with sophisticated technology and are arguably undetectable by biologic systems and, hence, harmless. But a host of biologic ...

Adair R.K.

1995-11-09T23:59:59.000Z

86

Effect of electron density profile on power absorption of high frequency electromagnetic waves in plasma  

SciTech Connect (OSTI)

Considering different typical electron density profiles, a multi slab approximation model is built up to study the power absorption of broadband (0.75-30 GHz) electromagnetic waves in a partially ionized nonuniform magnetized plasma layer. Based on the model, the power absorption spectra for six cases are numerically calculated and analyzed. It is shown that the absorption strongly depends on the electron density fluctuant profile, the background electron number density, and the collision frequency. A potential optimum profile is also analyzed and studied with some particular parameters.

Xi Yanbin; Liu Yue [MOE Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

2012-07-15T23:59:59.000Z

87

Low Frequency Electromagnetic Fields in High Contrast Media ?  

E-Print Network [OSTI]

ow monitoring, in underground contaminant detection, etc. In this paper we will focus attention, such as hydrocarbons, are poor conductors in comparison with other pore liquids, such as brines [4, 33]. Thus

Papanicolaou, George C.

88

Low Frequency Electromagnetic Fields in High Contrast Media ?  

E-Print Network [OSTI]

flow monitoring, in underground contaminant detection, etc. In this paper we will focus attention, such as hydrocarbons, are poor conductors in comparison with other pore liquids, such as brines [4, 33]. Thus

Borcea, Liliana

89

6.641 Electromagnetic Fields, Forces, and Motion, Spring 2003  

E-Print Network [OSTI]

Electric and magnetic quasistatic forms of Maxwell's equations applied to dielectric, conduction, and magnetization boundary value problems. Electromagnetic forces, force densities, and stress tensors, including magnetization ...

Zahn, Markus, 1946-

90

Electromagnetically induced transparency controlled by a microwave field  

E-Print Network [OSTI]

interferences in electromagnetically induced transparency. A simple theoretical model and a numerical simulation have been developed to explain the observed experimental results....

Li, Hebin; Sautenkov, Vladimir A.; Rostovtsev, Yuri V.; Welch, George R.; Hemmer, Philip R.; Scully, Marlan O.

2009-01-01T23:59:59.000Z

91

Lichnerowicz-Type Theorems for Self-gravitating Systems with Nonlinear Electromagnetic Fields  

E-Print Network [OSTI]

We consider a self-gravitating system containing a globally timelike Killing vector and a nonlinear Born-Infeld electromagnetic field and scalar fields. We prove that under certain boundary conditions (asymptotically flat/AdS) there can't be any nontrivial field configurations in the spacetime. To explore nontrivial solutions one should break any of the conditions we imposed. The case with another type of nonlinear electromagnetic field is also analyzed, and similar conclusions have been obtained under certain conditions.

Li-Ming Cao; Yuxuan Peng; Jianfei Xu

2014-07-11T23:59:59.000Z

92

Exact solution to the Landau-Lifshitz equation in a constant electromagnetic field  

E-Print Network [OSTI]

We are interested in the motion of a classical charge acted upon an external constant electromagnetic field where the back reaction of the particle's own field is taken into account. The Landau-Lifshitz approximation to the Lorentz-Abraham-Dirac equation is solved exactly and in closed form. It is shown that the ultrarelativistic limit of the Landau-Lifshitz equation for a radiating charge is the equation for eigenvalues and eigenvectors of the external electromagnetic field tensor.

Yurij Yaremko

2014-12-04T23:59:59.000Z

93

Low-Frequency Electromagnetic Response Function for Strong-Coupling Superconductors  

E-Print Network [OSTI]

properties of superconduc- tors is well known. For example, the frequency dependence of the electrical conductivity in strong- coupling superconductors has been observed by both infrared" and microwave' techniques. Also, the magnitude and temperature... dependence of the low-frequency conductivity for Pb have been in- ferred from measurements of magnetic field at- tenuation, ' while kinetic inductance' measure- ments have been used to study this temperature dependence for amorphous superconductors...

SCHOLTEN, PD; LEJEUNE, JD; SASLOW, WM; Naugle, Donald G.

1977-01-01T23:59:59.000Z

94

Pressure-induced OH frequency downshift in brucite: frequency-distance and frequency-field correlations  

Science Journals Connector (OSTI)

The ordered Mg(OH)2 crystal structure has been optimized for different pressures in the pressure range 0-21 GPa, within the trigonal P m1 space group. Anharmonic frequencies for the Raman-active OH vibrational mode were calculated from potential energy curves obtained by B3LYP and PW91 calculations with the CRYSTAL06 program. We find that an external pressure leads to an OH frequency downshift, in agreement with experiment, but there are no hydrogen bonds involved. The frequency downshift depends linearly on the electric field exerted on the OH ions from its neighbours in the 'opposite' layer. In agreement with experiment we also find that the pressure-induced 'v(OH) vs. interlayer R(O - - - O)' curve deviates from the well established correlation curves for hydrogen-bonded systems in the literature; the ?v/?R slope for high pressure conditions is much smaller. We also point out the merits of reporting both v(OH) and ?vgas-to-solid for comparison with experiment.

K Hermansson; G Gajewski; P D Mitev

2008-01-01T23:59:59.000Z

95

Laser frequency stabilization to excited state transitions using electromagnetically induced transparency in a cascade system  

SciTech Connect (OSTI)

We demonstrate laser frequency stabilization to excited state transitions using cascade electromagnetically induced transparency. Using a room temperature Rb vapor cell as a reference, we stabilize a first diode laser to the D{sub 2} transition and a second laser to a transition from the intermediate 5P{sub 3/2} state to a highly excited state with principal quantum number n=19-70. A combined laser linewidth of 280{+-}50 kHz over a 100 {mu}s time period is achieved. This method may be applied generally to any cascade system and allows laser stabilization to an atomic reference in the absence of a direct absorption signal.

Abel, R. P.; Mohapatra, A. K.; Bason, M. G.; Pritchard, J. D.; Weatherill, K. J.; Raitzsch, U.; Adams, C. S. [Department of Physics, Durham University, Rochester Building, South Road, Durham DH1 3LE (United Kingdom)

2009-02-16T23:59:59.000Z

96

Study of Electromagnetic Field (EMF) on the Human Muscle Activity: A Preliminary Study  

Science Journals Connector (OSTI)

During the 20th century, environmental exposure to man-made electromagnetic fields has been steadily increasing as growing electricity demand, ever-advancing technologies and changes in social behaviour have c...

Mohd Shuhaibul Fadly Mansor

2008-01-01T23:59:59.000Z

97

Gravitation and electromagnetism in theory of a unified four-vector field  

E-Print Network [OSTI]

A four-vector field in flat space-time, satisfying a gauge-invariant set of second-order differential equations, is considered as a unified field. The model variational principle corresponds to the general covariance idea and gives rise to nonlinear Born-Infeld electrodynamics. Thus the four-vector field is considered as an electromagnetic potential. It is suggested that space-localized (particle) solutions of the nonlinear field model correspond to material particles. Electromagnetic and gravitational interactions between field particles appear naturally when a many-particle solution is investigated with the help of a perturbation method. The electromagnetic interaction appears in the first order in the small field of distant particles. In the second order, there is an effective Riemannian space induced by the field of distant particles. This Riemannian space can be connected with gravitation.

Alexander A. Chernitskii

2006-09-28T23:59:59.000Z

98

Electromagnetic fields and transport coefficients in a hot pion gas  

E-Print Network [OSTI]

We present recent results on finite temperature electromagnetic form factors and the electrical conductivity in a pion gas. The standard Chiral Perturbation Theory power counting needs to be modified for transport coefficients. We pay special attention to unitarity and to possible applications for dilepton and photon production.

A. Gomez Nicola; D. Fernandez-Fraile

2006-08-24T23:59:59.000Z

99

Utilization of electromagnetic detector for selection and detection of high-frequency relic gravitational waves  

E-Print Network [OSTI]

It is shown that coupling system between fractal membranes and a Gaussian beam passing through a static magnetic field has strong selection capability for the stochastic relic gravitational wave background. The relic GW components propagating along the positive direction of the symmetrical axis of the Gaussian beam might generate an optimal electromagnetic perturbation while the perturbation produced by the relic GW components propagating along the negative and perpendicular directions to the symmetrical axis will be much less than the former.The influence of the random fluctuation of the relic GWs to such effect can be neglected and the influence of the random fluctuation of the relic GWs to such effect can be neglected.

Fangyu Li; Zhenya Chen; Ying Yi

2005-11-03T23:59:59.000Z

100

Total cross-section for photon-axion conversions in external electromagnetic field  

E-Print Network [OSTI]

We reconsider the conversion of the photon into axion in the external electromagnetic fields, namely in the static fields and in a periodic field of the wave guide. The total cross-sections for the conversion are evaluated in detail. The result shows that with strong strength of external electromagnetic fields, the cross-sections are large enough to measure the axion production. In the wave guide there exists the resonant conversion at the low energies, in which the value of cross-sections is much enhanced

D. V. Soa; H. N. Long; T. D. Tham

2014-02-20T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

The Breakdown of Gases in High Frequency Electrical Fields  

Science Journals Connector (OSTI)

A theory is proposed to explain the mechanism of breakdown of gases in high frequency electrical fields. It is assumed that breakdown occurs when the electrical field and the frequency are such that an electron acquires the ionizing energy at the end of one mean free path. The field for breakdown is thus a function of the frequency of the applied potential and the ionization potential and pressure of the gas. The fields for breakdown of argon and xenon are calculated and expressed as functions of the frequency and the gas pressure. The calculated potentials are compared with experimental data, and good agreement is found for frequencies greater than 10106 c.p.s.

Donald H. Hale

1948-05-01T23:59:59.000Z

102

Electromagnetics  

Science Journals Connector (OSTI)

... , Ampere, Neumann, Riemann, Weber and Lorenz, and their successors, Voight, Lienard, Schwarzschild and Ritz, based on action at a distance between discrete charges and the assumption ... discarded the concepts of electric and magnetic fields, and takes his stand on the Lidnard-Schwarzschild force formula, which appears to be eqxiivalent to the simple vector formula given by ...

C. V. DRYSDALE

1939-07-15T23:59:59.000Z

103

Efficient Inversion of Mult-frequency and Multi-Source Electromagnetic Data  

SciTech Connect (OSTI)

The project covered by this report focused on development of efficient but robust non-linear inversion algorithms for electromagnetic induction data, in particular for data collected with multiple receivers, and multiple transmitters, a situation extremely common in eophysical EM subsurface imaging methods. A key observation is that for such multi-transmitter problems each step in commonly used linearized iterative limited memory search schemes such as conjugate gradients (CG) requires solution of forward and adjoint EM problems for each of the N frequencies or sources, essentially generating data sensitivities for an N dimensional data-subspace. These multiple sensitivities allow a good approximation to the full Jacobian of the data mapping to be built up in many fewer search steps than would be required by application of textbook optimization methods, which take no account of the multiplicity of forward problems that must be solved for each search step. We have applied this idea to a develop a hybrid inversion scheme that combines features of the iterative limited memory type methods with a Newton-type approach using a partial calculation of the Jacobian. Initial tests on 2D problems show that the new approach produces results essentially identical to a Newton type Occam minimum structure inversion, while running more rapidly than an iterative (fixed regularization parameter) CG style inversion. Memory requirements, while greater than for something like CG, are modest enough that even in 3D the scheme should allow 3D inverse problems to be solved on a common desktop PC, at least for modest (~ 100 sites, 15-20 frequencies) data sets. A secondary focus of the research has been development of a modular system for EM inversion, using an object oriented approach. This system has proven useful for more rapid prototyping of inversion algorithms, in particular allowing initial development and testing to be conducted with two-dimensional example problems, before approaching more computationally cumbersome three-dimensional problems.

Gary D. Egbert

2007-03-22T23:59:59.000Z

104

Radio frequency ion source operated with field effect transistor based radio frequency system  

SciTech Connect (OSTI)

Characteristics of radio frequency (RF) plasma production are investigated using a field effect transistor inverter power supply as an RF wave source. With the frequency of around 0.3 MHz, an electron density over 10{sup 18} m{sup -3} is produced in argon plasma. Although lower densities are obtained in hydrogen plasma, it drastically increased up to 5x10{sup 18} m{sup -3} with an axial magnetic field of around 100 G applied in the driver region. Effects of the magnetic field and gas pressure are investigated in the RF produced plasma with the frequency of several hundred kilohertz.

Ando, A.; Komuro, A.; Matsuno, T. [Department of Electrical Engineering, Tohoku University, Sendai 980-8759 (Japan); Tsumori, K.; Takeiri, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan)

2010-02-15T23:59:59.000Z

105

Chapter 1.6.7 - Biological Effects of Radio-Frequency Fields  

Science Journals Connector (OSTI)

Publisher Summary This chapter discusses the biological effect of radio-frequency (rf) fields. It has initiated many investigations on biological effects of low-level electromagnetic fields. The aim of the chapter is to present a critical review of the current knowledge of the effects of rf fields on biological systems and to introduce various setups designed to test the influence of rf fields on these systems especially for the mobile communication frequency range (200 \\{MHz\\} to 2.5 GHz). In experiments whose aim is to test the effects of rf fields on technical or biological systems, the design of the exposure setup is a very important step. Insufficient knowledge of the field distribution inside the specimen will lead to wrong results. Independent of the outcome itself, wrong positive as well as wrong negative results may be the consequence and the experimental work and the money invested will be wasted. Testing the effects of rf fields on biological systems needs both detailed knowledge about the actual field distribution inside the specimen and well-documented reliable biological processes whose potential changes may finally be put down to the presence of an rf field.

R. Meyer; J. Streckert; V. Hansen

2002-01-01T23:59:59.000Z

106

Free Form of the Foldy-Wouthuysen Transformation in External Electromagnetic Fields  

E-Print Network [OSTI]

We derive the exact Foldy-Wouthuysen transformation for Dirac fermions in a time independent external electromagnetic field in the basis of the Ritus eigenfunctions, namely the eigenfunctions of the operator $(\\gamma \\cdot \\Pi)^2$, with $\\Pi^\\mu = p^\\mu - e A^\\mu$. In this basis, the transformation acquires a free form involving the dynamical quantum numbers induced by the field.

Gabriela Murguia; Alfredo Raya

2010-08-29T23:59:59.000Z

107

Lagrangian formulation of massive fermionic higher spin fields on a constant electromagnetic background  

E-Print Network [OSTI]

We consider massive half-integer higher spin fields coupled to an external constant electromagnetic field in flat space of an arbitrary dimension and construct a gauge invariant Lagrangian in the linear approximation in the external field. A procedure for finding the gauge-invariant Lagrangians is based on the BRST construction where no off-shell constraints on the fields and on the gauge parameters are imposed from the very beginning. As an example of the general procedure, we derive a gauge invariant Lagrangian for a massive fermionic field with spin 3/2 which contains a set of auxiliary fields and gauge symmetries.

Buchbinder, I L; Tsulaia, M

2015-01-01T23:59:59.000Z

108

1D subsurface electromagnetic fields excited by energized steel casing  

E-Print Network [OSTI]

of the simula- tions when benchmarked against the whole-space solution of EM fields excited by a vertical, typical interwell spacing in conven- tional oil fields is approximately 1 km, whereas the maximum inter importantly, the relatively high cost of deployment and acquisition, coupled with high levels of measure- ment

Torres-Verdín, Carlos

109

Generation of electromagnetic radiation based on nanotubes under a constant electric field and an electromagnetic wave field  

SciTech Connect (OSTI)

The possible generation of radiation in the millimeter range based on nanotubes by an alternating (rapidly oscillating) electric field under a constant (or nonstationary) electric field is studied. Radiation enhancement is based on a periodic dependence of the current in nanotubes in such electric fields. The results of a mathematical simulation are presented.

Sadykov, N. R., E-mail: sadykov@rambler.ru; Scorkin, N. A. [South Ural State University (Russian Federation)

2012-02-15T23:59:59.000Z

110

Multipole expansions of electromagnetic fields using Debye potentials  

Science Journals Connector (OSTI)

The Debye potentials are introduced by giving new derivations of the multipole expansions of the magnetostatic and electrostatic fields. Simplified derivations of the multipole expansions of the electrodynamic fields are then given. The radiated energy momentum and angular momentum are all calculated in the same manner i.e. using the proper transport equations. The questions of uniqueness and completeness of the Debye potential representations of the fields are discussed. In the Appendices are collected together some useful vector fieldtheorems and operator identities involving the angular momentum operator and also simplified derivations of the spherical harmonic expansions of the static and dynamic Green functions.

C. G. Gray

1978-01-01T23:59:59.000Z

111

Ion acoustic wave generation by a standing electromagnetic field in a subcritical plasma  

E-Print Network [OSTI]

233 Ion acoustic wave generation by a standing electromagnetic field in a subcritical plasma P.5 03BCs) is launched into a subcritical argon plasma (ne ~1011 cm-3, P0 ~ 5 10-4 Torr), resulting.35 1. Introduction. Our purpose is to study the ion acoustic wave excited in a subcritical plasma

Boyer, Edmond

112

ELECTROMAGNETIC POLARIZATION IN PARTIALLY IONIZED PLASMAS WITH STRONG MAGNETIC FIELDS AND NEUTRON STAR ATMOSPHERE MODELS  

E-Print Network [OSTI]

of the relatively high atmosphere density, a proper treatment should take account of the plasma nonidealityELECTROMAGNETIC POLARIZATION IN PARTIALLY IONIZED PLASMAS WITH STRONG MAGNETIC FIELDS AND NEUTRON STAR ATMOSPHERE MODELS Alexander Y. Potekhin,1, 2 Dong Lai,3 Gilles Chabrier,4 and Wynn C. G. Ho5, 6

113

ECEN 3410 -Electromagnetic Fields and Transmission Spring semester 2005, University of Colorado at Boulder  

E-Print Network [OSTI]

ECEN 3410 - Electromagnetic Fields and Transmission Spring semester 2005, University of Colorado the resistor. 14. The current intensity through a coil of inductance L is i(t). Find the flux of the Poynting vector through any closed surface enclosing the coil. 15. Why do we care about boundary conditions? How

Piestun, Rafael

114

Power Drive Investigation by Spectral Analysis of the Electromagnetic Field Emitted by the  

E-Print Network [OSTI]

. One notes that all the power transit throught the DC bus bar of the inverter [6] [7] [8]. Not onlyPower Drive Investigation by Spectral Analysis of the Electromagnetic Field Emitted by the DC Bus analysis and/or motor current sig- nature analysis (weel known as MCSA). This paper presents a new approach

Boyer, Edmond

115

On the Electrodynamics of Moving Permanent Dipoles in External Electromagnetic Fields  

E-Print Network [OSTI]

The classical theory of electrodynamics is built upon Maxwell's equations and the concepts of electromagnetic field, force, energy and momentum, which are intimately tied together by Poynting's theorem and the Lorentz force law. Whereas Maxwell's macroscopic equations relate the electric and magnetic fields to their material sources (i.e., charge, current, polarization and magnetization), Poynting's theorem governs the flow of electromagnetic energy and its exchange between fields and material media, while the Lorentz law regulates the back-and-forth transfer of momentum between the media and the fields. The close association of momentum with energy thus demands that the Poynting theorem and the Lorentz law remain consistent with each other, while, at the same time, ensuring compliance with the conservation laws of energy, linear momentum, and angular momentum. This paper shows how a consistent application of the aforementioned laws of electrodynamics to moving permanent dipoles (both electric and magnetic) b...

Mansuripur, Masud

2014-01-01T23:59:59.000Z

116

Interacting Scalar and Electromagnetic Fields in $f(R,\\,T)$ Theory of Gravity  

E-Print Network [OSTI]

Within the scope of $f(R,\\,T)$ gravity we have studied the interacting scalar and electromagnetic fields in a Bianchi type I universe. It was found that if the study is confined to the case $f(R,\\,T) = R + \\lambda f(T)$, the system is completely given by the equations similar to Einstein gravity. Moreover, the present study imposes some severe restrictions on the field equations as well.

Bijan Saha

2014-10-07T23:59:59.000Z

117

Controlling molecular collisions with electromagnetic fields Roman Krems  

E-Print Network [OSTI]

External field (Shapiro, ...) Coherent control Controlled dynamics #12;External electric or magnetic elds coo #12;Bose-Einstein Condensate Experimental confirmation - 1995, E.A. Cornell, C. E confirmation - 1995 E. A. Cornell, C. E Wieman, W. Ketterle Ultracold gas of Rb atoms at T ~ 0.0000002 Kelvin

Krems, Roman

118

An Adaptive Fast Multipole Higher Order Boundary Element Method for Power Frequency Electric Field of Substation  

Science Journals Connector (OSTI)

An adaptive fast multipole higher order boundary element method combining fast multipole (FM) with a higher order boundary element method is studied to solve the power frequency electric field (PFEF) of substations. In this new technique, the iterative equation solver GMRES is used in the FM, where matrix-vector multiplications are calculated using fast multipole expansions. The coefficients in the preconditioner for GMRES are stored and are used repeatedly in the direct evaluations of the near-field contributions. Then a 500kV outdoor substation is modeled and the PFEF of the substation is analyzed by the novel algorithm and other conventional methods. The results show that, in computational cost and the storages capability aspects, the algorithm proposed in this study has obvious advantages. It is suitable for the calculation of the large-scale PFEF in complex substations and the design of electromagnetic compatibility.

Zhang Zhan-Long; Deng Jun; Xiao Dong-Ping; He Wei; Tang Ju

2010-01-01T23:59:59.000Z

119

Harmonic filters influences regarding the power quality on high frequency electrothermal installation with electromagnetic induction  

Science Journals Connector (OSTI)

This paper presents a study regarding the functioning of a melting/hardening electrothermal installation with electromagnetic induction from the point of view of generated harmonics in the power distribution. The authors made simulations in scope of ... Keywords: electrothermal installation, harmonic, passive filters, static converter

Raluca Rob; Ioan Sora; Caius Panoiu; Manuela Panoiu

2010-01-01T23:59:59.000Z

120

Enhancement of electromagnetic propagation through complex media for Radio Frequency Identification  

E-Print Network [OSTI]

In this thesis, I present and examine the fundamental limitations involved in Radio Frequency Identification (RFID) as well as provide a means to improve reader-tag communication in ultra high frequency RFID systems. The ...

Marti, Uttara P

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Electromagnetic Theory 1 /56 Electromagnetic Theory  

E-Print Network [OSTI]

Electromagnetic Theory 1 /56 Electromagnetic Theory Summary: · Maxwell's equations · EM Potentials · Equations of motion of particles in electromagnetic fields · Green's functions · Lienard-Weichert potentials · Spectral distribution of electromagnetic energy from an arbitrarily moving charge #12;Electromagnetic

Bicknell, Geoff

122

Fundamental physics on natures of the macroscopic vacuum under high intense electromagnetic fields with accelerators  

E-Print Network [OSTI]

High intense electromagnetic fields can be unique probes to study natures of macroscopic vacua by themselves. Combining accelerators with the intense field can provide more fruitful probes which can neither be achieved by only intense fields nor only high energy accelerators. We will overview the natures of vacua which can be accessible via intense laser-laser and intense laser-electron interactions. In the case of the laser-laser interaction, we propose how to observe nonlinear QED effects and effects of new fields like light scalar and pseudo scalar fields which may contribute to a macroscopic nature of our universe such as dark energy. In the case of the laser-electron interaction, in addition to nonlinear QED effects, we can further discuss the nature of accelerating field in the vacuum where we can access physics related with event horizons such as Hawking-Unruh radiations. We will introduce a recent experimental trial to search for this kind of odd radiations.

Kensuke Homma

2009-11-30T23:59:59.000Z

123

Health effects of electromagnetic field generated by lightning current pulses near down conductors  

Science Journals Connector (OSTI)

The lightning current generates a time varying magnetic field near down conductors, when lightning strikes the connected Franklin-rod. The down conductors are mounted on the wall of buildings, where residential places can be situated. It is well known that the rapidly changing magnetic fields could generate dangerous eddy currents in the human body. If the duration and the gradient of the magnetic field were high enough, the peripheral nerves are excited. In this study, the authors introduce an improved model of the interaction of electromagnetic fields of lighting current near a down conductor with the human body. The interaction model has two parts: estimation of the magnetic fields surrounding the down conductor and evaluation of health effects of rapid changing magnetic fields on the human body.

Z Tamus; B Novk; L Szcs; I Kiss

2011-01-01T23:59:59.000Z

124

Laboratory Studies of the Short-term Responses of Freshwater Fish to Electromagnetic Fields  

SciTech Connect (OSTI)

Hydrokinetic energy technologies are being proposed as an environmentally preferred means of generating electricity from river and tidal currents. Among the potential issues that must be investigated in order to resolve environmental concerns are the effects on aquatic organisms of electromagnetic fields created by underwater generators and transmission cables. The behavioral responses of common freshwater fishes to static and variable electromagnetic fields (EMF) that may be emitted by hydrokinetic projects were evaluated in laboratory experiments. Various fish species were exposed to either static (DC) EMF fields created by a permanent bar magnet or variable (AC) EMF fields created by a switched electromagnet for 48 h, fish locations were recorded with a digital imaging system, and changes in activity level and distribution relative to the magnet position were quantified at 5-min intervals. Experiments with fathead minnows, redear sunfish, striped bass, lake sturgeon, and channel catfish produced mixed results. Except for fathead minnows there was no effect on activity level. Only redear sunfish and channel catfish exhibited a change in distribution relative to the position of the magnet with an apparent attraction to the EMF source. In separate experiments, rapid behavioral responses of paddlefish and lake sturgeon to onset of the AC field were recorded with high-speed video. Paddlefish did not react to a variable, 60-Hz magnetic field like that which would be emitted by an AC generator or cable, but lake sturgeon consistently responded to the variable, AC-generated magnetic field with a variety of altered swimming behaviors. These results will be useful for determining under what circumstances cables or generators need to be positioned to minimize interactions with sensitive species.

Bevelhimer, Mark S [ORNL; Cada, Glenn F [ORNL; Fortner, Allison M [ORNL; Schweizer, Peter E [ORNL; Riemer, Kristina P [ORNL

2013-01-01T23:59:59.000Z

125

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

SciTech Connect (OSTI)

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.

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

2012-06-15T23:59:59.000Z

126

Development of an international standard for electromagnetic interference (EMI)/radio frequency interference (RFI)  

SciTech Connect (OSTI)

This paper covers the development of an international standard that establishes the requirements for electromagnetic compatibility testing of instrumentation and control equipment supplied for use in systems important to safety at nuclear power plants. The standard lists the applicable IEC standards (principally the IEC 61000 series) which define the general test methods, and provides the necessary application-specific parameters and criteria to ensure that nuclear safety requirements are met. This standard was prepared with the leadership by the Russian National Committee representatives to the International Electrotechnical Commission (IEC). (authors)

Sarylov, V. [EMC Test Center, NUIT, FSUE RIPT, Moscow (Russian Federation); Shumov, S. [FSUE SEC SNIIP, Moscow (Russian Federation); Quinn, E. [ANS, Dana Point, CA (United States)

2006-07-01T23:59:59.000Z

127

Magneto-optic and electro-optic effects in electromagnetic and gravitational fields  

E-Print Network [OSTI]

The magneto-optic effects and electro-optic effects are the essential optic effects, although their theoretical explanations are not unified in the classical electromagnetic theory. Describing with the algebra of octonions, the electromagnetic theory can derive the magneto-optic effects and electro-optic effects from the same one force definition in the paper. As well as the magneto-optic effect is deduced from the known force term, the electro-optic effect is from the new force term in the octonion space. This description method is different to that in the quantum theory as well as the index ellipsoid approach for the electro-optic effect. One more significant inference is that the gravitational field has an impact on the rotation of linearly polarized light, and then results in the similar birefringence for the transmitted light in the cosmic matter.

Zi-Hua Weng

2010-11-26T23:59:59.000Z

128

Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes  

DOE Patents [OSTI]

An accelerating cavity is disclosed having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps. 17 figures.

Palmer, R.B.

1991-05-21T23:59:59.000Z

129

Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes  

DOE Patents [OSTI]

An accelerating cavity having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps.

Palmer, Robert B. (Shoreham, NY)

1991-01-01T23:59:59.000Z

130

Transferrin Binding to Two Human Colon Carcinoma Cell Lines: Characterization and Effect of 60-Hz Electromagnetic Fields  

Science Journals Connector (OSTI)

...cyclase activity in response to low-level...Iron transport and storage proteins. Ann...inhibition of responses to parathyroid hormone by tow-energy, low-frequency fields. Proc...constant and low-frequency magnetic fields...

Jerry L. Phillips; Loyce Rutledge; and Wendell D. Winters

1986-01-01T23:59:59.000Z

131

Particle dynamics and deviation effects in the field of a strong electromagnetic wave  

E-Print Network [OSTI]

Some strong field effects on test particle motion associated with the propagation of a plane electromagnetic wave in the exact theory of general relativity are investigated. Two different profiles of the associated radiation flux are considered in comparison, corresponding to either constant or oscillating electric and magnetic fields with respect to a natural family of observers. These are the most common situations to be experimentally explored, and have a well known counterpart in the flat spacetime limit. The resulting line elements are determined by a single metric function, which turns out to be expressed in terms of standard trigonometric functions in the case of a constant radiation flux, and in terms of special functions in the case of oscillating flux, leading to different features of test particle motion. The world line deviation between both uncharged and charged particles on different spacetime trajectories due to the combined effect of gravitational and electromagnetic forces is studied. The interaction of charged particles with the background radiation field is also discussed through a general relativistic description of the inverse Compton effect. Motion as well as deviation effects on particles endowed with spin are studied too. Special situations may occur in which the direction of the spin vector change during the interaction, leading to obsevables effects like spin-flip.

Donato Bini; Andrea Geralico; Maria Haney; Antonello Ortolan

2014-08-23T23:59:59.000Z

132

Spin oscillations of relativistic fermions in the field of a traveling circularly polarized electromagnetic wave and a constant magnetic field  

E-Print Network [OSTI]

The Dirac equation, in the field of a traveling circularly polarized electromagnetic wave and a constant magnetic field, has singular solutions, corresponding the expansion of energy in vicinity of some singular point. These solutions described relativistic fermions. States relating to these solutions are not stationary. The temporal change of average energy, momentum and spin for single and mixed states is studied in the paper. A distinctive feature of the states is the disappearance of the longitudinal component of the average spin. Another feature is the equivalence of the condition of fermion minimal energy and the classical condition of the magnetic resonance. Finding such solutions assumes the use of a transformation for rotating and co-moving frames of references. Comparison studies of solutions obtained with the Galilean and non-Galilean transformation shown that some parameters of the non-Galilean transformation may be measured in high-energy physics.

Boris V. Gisin

2014-05-13T23:59:59.000Z

133

Electromagnetic polarization in partially ionized plasmas with strong magnetic fields and neutron star atmosphere models  

E-Print Network [OSTI]

Polarizability tensor of a strongly magnetized plasma and the polarization vectors and opacities of normal electromagnetic waves are studied for the conditions typical of neutron star atmospheres, taking account of partial ionization effects. Vacuum polarization is also included using a new set of fitting formulae that are accurate for wide range of field strengths. The full account of the coupling of the quantum mechanical structure of the atoms to their center-of-mass motion across the magnetic field is shown to be crucial for the correct evaluation of the polarization properties and opacities of the plasma. The self-consistent treatment of the polarizability and absorption coefficients proves to be necessary if the ionization degree of the plasma is low, which can occur in the atmospheres of cool or ultramagnetized neutron stars. Atmosphere models and spectra are presented to illustrate the importance of such self-consistent treatment.

A. Y. Potekhin; Dong Lai; G. Chabrier; W. C. G. Ho

2004-05-20T23:59:59.000Z

134

Line narrowing of electromagnetically induced transparency in Rb with a longitudinal magnetic field  

Science Journals Connector (OSTI)

Electromagnetically induced transparency (EIT) experiments in ?-type systems benefit from the use of hot vapor where the thermal averaging results in reducing the width of the EIT resonance well below the natural linewidth. Here, we demonstrate a technique for further reducing the EIT width in room-temperature vapor by the application of a small longitudinal magnetic field. The Zeeman shift of the energy levels results in the formation of several shifted subsystems; the net effect is to create multiple EIT dips each of which is significantly narrower than the original resonance. We observe a reduction by a factor of 3 in the D2 line of Rb87 with a field of 3.2G.

S. M. Iftiquar and Vasant Natarajan

2009-01-12T23:59:59.000Z

135

Electromagnetic partner of the gravitational signal during accretion onto black holes  

E-Print Network [OSTI]

We investigate the generation of electromagnetic and gravitational radiation in the vicinity of a perturbed Schwarzschild black hole. The gravitational perturbations and the electromagnetic field are studied by solving the Teukolsky master equation with sources, which we take to be locally charged, radially infalling, matter. Our results show that, in addition to the gravitational wave generated as the matter falls into the black hole, there is also a burst of electromagnetic radiation. This electromagnetic field has a characteristic set of quasinormal frequencies, and the gravitational radiation has the quasinormal frequencies of a Schwarzschild black hole. This scenario allows us to compare the gravitational and electromagnetic signals that are generated by a common source.

Juan Carlos Degollado; Victor Gualajara; Claudia Moreno; Daro Nez

2014-10-21T23:59:59.000Z

136

Source-free electromagnetism's canonical fields reveal the free-photon Schroedinger equation  

E-Print Network [OSTI]

Classical equations of motion that are first-order in time and conserve energy can only be quantized after their variables have been transformed to canonical ones, i.e., variables in which the energy is the system's Hamiltonian. The source-free version of Maxwell's equations is purely dynamical, first-order in time and has a well-defined nonnegative conserved field energy, but is decidedly noncanonical, an issue that has attracted little attention. The opposite parities of the electric and magnetic fields and consequent curl operations that typify Maxwell's equations are especially at odds with their being canonical fields. Transformation of the magnetic field into the transverse part of the vector potential helps but is not sufficient; further simple nonnegative symmetric integral transforms, which commute with all differential operators, are needed for both fields; such transforms also supplant the curls in the equations of motion. The canonical replacements of the source-free electromagnetic fields remain transverse-vector fields, but are more diffuse than their predecessors. Combined as the real and imaginary parts of a complex field, the canonical fields prove to be the transverse-vector wave function of a time-dependent Schroedinger equation whose Hamiltonian operator is the quantization of the free photon's square-root relativistic energy. Thus proper quantization of the source-free Maxwell equations is identical to second quantization of free photons that have normal square-root energy. There is no physical reason why first and second quantization of any relativistic free particle ought not to proceed in precise parallel, utilizing the square-root Hamiltonian operator. This natural procedure leaves no role for the completely artificial Klein-Gordon and Dirac equations, as accords with their grossly unphysical properties.

Steven Kenneth Kauffmann

2010-11-29T23:59:59.000Z

137

Nonlinear Electrodynamics: Alternative Field Theory for Featuring Photon Propagation Over Weak Background Electromagnetic Fields and what Earth Receivers Read off Radio Signals from Interplanetary Spacecraft Transponders  

E-Print Network [OSTI]

A few observational and/or experimental results have dramatically pushed forward the research program on gravity as those from the radio-metric Doppler tracking received from the Pioneer 10 and 11 spacecrafts when the space vehicles were at heliocentric distances between 20 and 70 Astronomical Units (AU). These data have conclusively demonstrated the presence of an anomalous, tiny and blue-shifted frequency drift that changes smoothly at a rate of $ \\sim 6 \\times 10^{-9}$ Hz s$^{-1}$. Those signals, if interpreted as a gravitational pull of the Sun on each Pioneer vehicle, translates into a deceleration of $a_P = (8.74\\pm 1.33) \\times 10^{-10}$ m s$^{-2}$. This Sunward acceleration appears to be a violation of Newton's inverse-square law of gravitation, and is referred to as the Pioneer anomaly, the nature of which remains still elusive to unveil. Within the theoretical framework of nonlinear electrodynamics (NLED) in what follows we will address this astrodynamics puzzle, which over the last fifteen years has challenged in a fundamental basis our understanding of gravitational physics. To this goal we will first, and briefly, review the history of the Pioneers 10 and 11 missions. Then a synopsis of currently available Lagrangian formulations of NLED is given. And finally, we present our solution of this enigma by invoking a special class of NLED theories featuring a proper description of electromagnetic phenomena taking place in environments where the strength of the (electro)magnetic fields in the background is decidedly low.

Herman J. Mosquera Cuesta

2011-05-13T23:59:59.000Z

138

Electromagnetic Dipole Radiation Fields, Shear-Free Congruences and Complex Center of Charge World Lines  

E-Print Network [OSTI]

We show that for asymptotically vanishing Maxwell fields in Minkowski space with non-vanishing total charge, one can find a unique geometric structure, a null direction field, at null infinity. From this structure a unique complex analytic world-line in complex Minkowski space that can be found and then identified as the complex center of charge. By ''sitting'' - in an imaginary sense, on this world-line both the (intrinsic) electric and magnetic dipole moments vanish. The (intrinsic) magnetic dipole moment is (in some sense) obtained from the `distance' the complex the world line is from the real space (times the charge). This point of view unifies the asymptotic treatment of the dipole moments For electromagnetic fields with vanishing magnetic dipole moments the world line is real and defines the real (ordinary center of charge). We illustrate these ideas with the Lienard-Wiechert Maxwell field. In the conclusion we discuss its generalization to general relativity where the complex center of charge world-line has its analogue in a complex center of mass allowing a definition of the spin and orbital angular momentum - the analogues of the magnetic and electric dipole moments.

Carlos N. Kozameh; Ezra T. Newman

2005-04-20T23:59:59.000Z

139

On the Casimir energy of the electromagnetic field in the dispersive and absorptive medium  

E-Print Network [OSTI]

The microscopic theory of the Casimir effect in the dielectric is studied in the framework when absorption is realized via a reservoir modeled by a set of oscillators with continuously distributed frquencies with the aim to see if the effects depend on the form of interaction with the reservoir. A simple case of the one-dimensional dielectric between two metallic plates is considered. Two possible models are investigated, the direct interaction of the electromagnetic field with the reservoir and indirect interaction via an intermediate oscillator imitating the atom. It is found that with the same dielectric constant the Casimir effect is different in these two cases, which implies that in the second model it cannot be entirely expressed via the dielectric constant as in the well-known Lifshitz formula.

M. A. Braun

2014-02-16T23:59:59.000Z

140

Momentum of electromagnetic fields, speed of light in moving media, and the photon mass  

E-Print Network [OSTI]

In both the equations for matter and light wave propagation, the momentum of the electromagnetic fields Pe reflects the relevant em interaction. As a review of some applications of wave propagation properties, an optical experiment which tests the speed of light in moving rarefied gases is described. Moreover, Pe is also the link to the unitary vision of the quantum effects of the Aharonov-Bohm (AB) type, which provide a useful quantum approach for the limit of the photon mass mph. A bench-top experiment based on effects of the AB type that exploit new interferometric techniques, is foreseen to yield the limit mph = 10^-54 g, a value that improves upon the results achieved with other approaches.

Gianfranco Spavieri; George T. Gillies

2010-05-21T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Electromagnetic Heating Methods for Heavy Oil Reservoirs  

SciTech Connect (OSTI)

The most widely used method of thermal oil recovery is by injecting steam into the reservoir. A well-designed steam injection project is very efficient in recovering oil, however its applicability is limited in many situations. Simulation studies and field experience has shown that for low injectivity reservoirs, small thickness of the oil-bearing zone, and reservoir heterogeneity limits the performance of steam injection. This paper discusses alternative methods of transferring heat to heavy oil reservoirs, based on electromagnetic energy. They present a detailed analysis of low frequency electric resistive (ohmic) heating and higher frequency electromagnetic heating (radio and microwave frequency). They show the applicability of electromagnetic heating in two example reservoirs. The first reservoir model has thin sand zones separated by impermeable shale layers, and very viscous oil. They model preheating the reservoir with low frequency current using two horizontal electrodes, before injecting steam. The second reservoir model has very low permeability and moderately viscous oil. In this case they use a high frequency microwave antenna located near the producing well as the heat source. Simulation results presented in this paper show that in some cases, electromagnetic heating may be a good alternative to steam injection or maybe used in combination with steam to improve heavy oil production. They identify the parameters which are critical in electromagnetic heating. They also discuss past field applications of electromagnetic heating including technical challenges and limitations.

Sahni, A.; Kumar, M.; Knapp, R.B.

2000-05-01T23:59:59.000Z

142

State Primary Standard of the Unit of Energy Flux of an Electromagnetic Field in the Range 0.378 GHz  

Science Journals Connector (OSTI)

We report the results of studies of the new measurement standards GT 160-00. The primary standard ... to reproduce and transfer the size of the unit of electromagnetic energy flux in the frequency range 0.3...

S. A. Kolotygin; V. A. Tishchenko; L. N. Bryanskii

2000-12-01T23:59:59.000Z

143

Kinetic equilibria of relativistic collisionless plasmas in the presence of non-stationary electromagnetic fields  

SciTech Connect (OSTI)

The kinetic description of relativistic plasmas in the presence of time-varying and spatially non-uniform electromagnetic (EM) fields is a fundamental theoretical issue both in astrophysics and plasma physics. This refers, in particular, to the treatment of collisionless and strongly-magnetized plasmas in the presence of intense radiation sources. In this paper, the problem is investigated in the framework of a covariant gyrokinetic treatment for VlasovMaxwell equilibria. The existence of a new class of kinetic equilibria is pointed out, which occur for spatially-symmetric systems. These equilibria are shown to exist in the presence of non-uniform background EM fields and curved space-time. In the non-relativistic limit, this feature permits the determination of kinetic equilibria even for plasmas in which particle energy is not conserved due to the occurrence of explicitly time-dependent EM fields. Finally, absolute stability criteria are established which apply in the case of infinitesimal symmetric perturbations that can be either externally or internally produced.

Cremaschini, Claudio, E-mail: claudiocremaschini@gmail.com; Stuchlk, Zden?k [Faculty of Philosophy and Science, Institute of Physics, Silesian University in Opava, Bezru?ovo nm.13, CZ-74601 Opava (Czech Republic)] [Faculty of Philosophy and Science, Institute of Physics, Silesian University in Opava, Bezru?ovo nm.13, CZ-74601 Opava (Czech Republic); Tessarotto, Massimo [Faculty of Philosophy and Science, Institute of Physics, Silesian University in Opava, Bezru?ovo nm.13, CZ-74601 Opava (Czech Republic) [Faculty of Philosophy and Science, Institute of Physics, Silesian University in Opava, Bezru?ovo nm.13, CZ-74601 Opava (Czech Republic); Department of Mathematics and Geosciences, University of Trieste, Via Valerio 12, 34127 Trieste (Italy)

2014-03-15T23:59:59.000Z

144

A Topological Structure in the Set of Classical Free Radiation Electromagnetic Fields  

E-Print Network [OSTI]

The aim of this work is to proceed with the development of a model of topological electromagnetism in empty space, proposed by one of us some time ago and based on the existence of a topological structure associated with the radiation fields in standard Maxwell's theory. This structure consists in pairs of complex scalar fields, say $\\phi$ and $\\theta$, that can be interpreted as maps $\\phi,\\theta: S^3\\mapsto S^2$, the level lines of which are orthogonal to one another, where $S^3$ is the compactified physical 3-space $R^3$, with only one point at infinity, and $S^2$ is the 2-sphere identified with the complete complex plane. These maps were discovered and studied in 1931 by the German mathematician H. Hopf, who showed that the set of all of them can be ordered in homotopy classes, labeled by the so called Hopf index, equal to $\\gamma=\\pm 1,\\,\\pm 2,\\,\\cdots ,\\, \\pm k,...$ but without $\\gamma=0$. In the model presented here and at the level of the scalars $\\phi$ and $\\theta$, the equations of motion are highly nonlinear; however there is a transformation of variables that converts exactly these equations (not by truncation!) into the linear Maxwell's ones for the magnetic and electric fields $\\B$ and $\\E$.

A. F. Ranada; A. Tiemblo

2014-07-29T23:59:59.000Z

145

E-Print Network 3.0 - ambient electromagnetic fields Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Analysis Techniques Summary: & Technology Introduction Products fail electromagnetic interference (EMI) tests. This can be a disappointing... , and antenna. No single method...

146

Enhanced Electroporation in Plant Tissues via Low Frequency Pulsed Electric Fields: Influence of Cytoplasmic Streaming  

E-Print Network [OSTI]

Enhanced Electroporation in Plant Tissues via Low Frequency Pulsed Electric Fields: Influence (wileyonlinelibrary.com). Pulsed electric fields (PEF) are known to be effective at permeabilizing plant tissues: cytoplasmic streaming, molecular motor proteins, plant tissue integrity, viability staining, conductivity

Ristenpart, William

147

Using medaka embryos as a model system to study biological effects of the electromagnetic fields on development and behavior  

Science Journals Connector (OSTI)

Abstract The electromagnetic fields (EMFs) of anthropogenic origin are ubiquitous in our environments. The health hazard of extremely low frequency and radiofrequency \\{EMFs\\} has been investigated for decades, but evidence remains inconclusive, and animal studies are urgently needed to resolve the controversies regarding developmental toxicity of EMFs. Furthermore, as undersea cables and technological devices are increasingly used, the lack of information regarding the health risk of \\{EMFs\\} to aquatic organisms needs to be addressed. Medaka embryos (Oryzias latipes) have been a useful tool to study developmental toxicity in vivo due to their optical transparency. Here we explored the feasibility of using medaka embryos as a model system to study biological effects of \\{EMFs\\} on development. We also used a white preference test to investigate behavioral consequences of the EMF developmental toxicity. Newly fertilized embryos were randomly assigned to four groups that were exposed to an EMF with 3.2kHz at the intensity of 0.12, 15, 25, or 60T. The group exposed to the background 0.12T served as the control. The embryos were exposed continually until hatch. They were observed daily, and the images were recorded for analysis of several developmental endpoints. Four days after hatching, the hatchlings were tested with the white preference test for their anxiety-like behavior. The results showed that embryos exposed to all three levels of the EMF developed significantly faster. The endpoints affected included the number of somites, eye width and length, eye pigmentation density, midbrain width, head growth, and the day to hatch. In addition, the group exposed to the EMF at 60T exhibited significantly higher levels of anxiety-like behavior than the other groups did. In conclusion, the EMF tested in this study accelerated embryonic development and heightened anxiety-like behavior. Our results also demonstrate that the medaka embryo is a sensitive and cost-efficient in vivo model system to study developmental toxicity of EMFs.

Wenjau Lee; Kun-Lin Yang

2014-01-01T23:59:59.000Z

148

Residential proximity to electromagnetic field sources and birth weight: Minimizing residual confounding using multiple imputation and propensity score matching  

Science Journals Connector (OSTI)

Abstract Studies have suggested that residential exposure to extremely low frequency (50Hz) electromagnetic fields (ELF-EMF) from high voltage cables, overhead power lines, electricity substations or towers are associated with reduced birth weight and may be associated with adverse birth outcomes or even miscarriages. We previously conducted a study of 140,356 singleton live births between 2004 and 2008 in Northwest England, which suggested that close residential proximity (?50m) to ELF-EMF sources was associated with reduced average birth weight of 212g (95%CI: ?395 to ?29g) but not with statistically significant increased risks for other adverse perinatal outcomes. However, the cohort was limited by missing data for most potentially confounding variables including maternal smoking during pregnancy, which was only available for a small subgroup, while also residual confounding could not be excluded. This study, using the same cohort, was conducted to minimize the effects of these problems using multiple imputation to address missing data and propensity score matching to minimize residual confounding. Missing data were imputed using multiple imputation using chained equations to generate five datasets. For each dataset 115 exposed women (residing ?50m from a residential ELF-EMF source) were propensity score matched to 1150 unexposed women. After doubly robust confounder adjustment, close proximity to a residential ELF-EMF source remained associated with a reduction in birth weight of ?116g (95% confidence interval: ?224:?7g). No effect was found for proximity ?100m compared to women living further away. These results indicate that although the effect size was about half of the effect previously reported, close maternal residential proximity to sources of ELF-EMF remained associated with suboptimal fetal growth.

Frank de Vocht; Brian Lee

2014-01-01T23:59:59.000Z

149

ARM - Field Campaign - 2001 Multi-Frequency Radar IOP  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

govCampaigns2001 Multi-Frequency Radar IOP govCampaigns2001 Multi-Frequency Radar IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : 2001 Multi-Frequency Radar IOP 2001.03.01 - 2001.09.30 Lead Scientist : Stephen Sekelsky Data Availability http://abyss.ecs.umass.edu For data sets, see below. Summary Install UMass and NOAA Aeronomy Laboratory "guest instrument" radars at the SGP CART site adjacent to the MMCR system. Both the UMass and NOAA Aeronomy Laboratory systems will run autonomously for approximately a six month period. Description Scientific hypothesis: A. Measurements from the University of Massachusetts (UMass) Cloud Profiling Radar System (CPRS) - 95/33 GHz Radar indicate that the 95 GHz channel is much less sensitive to insect clutter than the 35 GHz channel by

150

Magnetic field probes for use in radio frequency plasma  

SciTech Connect (OSTI)

An impedance analyzer has been used in the characterization of a magnetic induction probe (B-dot probe) for use in plasma. The role of the impedance analyzer was to determine the frequency response of a B-dot probe up to 100 MHz. The probe was specifically designed to take measurements in rf plasma driven at 13.56 MHz. Probe sensitivity and calibration are considered based on the impedance values obtained when a B-dot probe is swept over a wide frequency range. Effects such as unbalanced loads based on transmission line inductances and termination impedance are shown to be limiting factors on the probes useful frequency range. The use of an impedance analyzer allows these effects to readily be characterized.

Reilly, Michael P.; Miley, George H. [Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois at Urbana-Champaign, 104 S. Wright Street, 216 Talbot Laboratory, MC-234 Urbana, Illinois 61801 (United States); Lewis, William [ERC Inc. Knight High School, 37423 70th Street East, Palmdale, California 93552 (United States)

2009-05-15T23:59:59.000Z

151

Position-dependent photon operators in the quantization of the electromagnetic field in dielectrics at local thermal equilibrium  

E-Print Network [OSTI]

It has very recently been suggested that asymmetric coupling of electromagnetic fields to thermal reservoirs under nonequilibrium conditions can produce unexpected oscillatory behavior in the local photon statistics in layered structures. Better understanding of the predicted phenomena could enable useful applications related to thermometry, noise filtering, and enhancing optical interactions. In this work we briefly review the field quantization and study the local steady state temperature distributions in optical cavities formed of lossless and lossy media to show that also local field temperatures exhibit oscillations that depend on position as well as the photon energy.

Mikko Partanen; Teppo Hyrynen; Jani Oksanen; Jukka Tulkki

2014-12-02T23:59:59.000Z

152

Measurements and modeling of radio frequency field structures in a helicon plasma  

SciTech Connect (OSTI)

Measurements of the radio frequency (rf) field structure, plasma density, and electron temperature are presented for a 1 kW argon helicon plasma source. The measured profiles change considerably when the equilibrium magnetic field is reversed. The measured rf fields are identified as fields of radially localized helicon waves, which propagate in the axial direction. The rf field structure is compared to the results of two-dimensional cold plasma full-wave simulations for the measured density profiles. Electron collision frequency is adjusted in the simulations to match the simulated and measured field profiles. The resulting frequency is anomalously high, which is attributed to the excitation of an ion-acoustic instability. The calculated power deposition is insensitive to the collision frequency and accounts for most of the power supplied by the rf-generator.

Lee, C. A. [University of Texas, Austin; Chen, Guangye [ORNL; Arefiev, A. V. [University of Texas, Austin; Bengtson, R. D. [University of Texas, Austin; Breizman, B. N. [University of Texas, Austin

2011-01-01T23:59:59.000Z

153

High-Frequency Conductivity of Quantum Plasma in a Magnetic Field  

Science Journals Connector (OSTI)

The problem of the electromagnetic absorption coefficient in a quantum plasma in the presence of a uniform magnetic field is investigated by a kinetic description. The finite duration of encounters is taken into account in a self-consistent fashion which includes collective effects properly. This treatment is the quantum extension of an earlier classical study. The application of this theory to heavily doped semiconductors is suggested.

Carl Oberman and Amiram Ron

1963-05-15T23:59:59.000Z

154

Quasinormal frequencies of the Dirac field in a D-dimensional Lifshitz black hole  

E-Print Network [OSTI]

In a D-dimensional Lifshitz black hole we calculate exactly the quasinormal frequencies of a test Dirac field in the massless and zero angular eigenvalue limits. These results are an extension of the previous calculations in which the quasinormal frequencies of the Dirac field are determined, but in four dimensions. We discuss the four-dimensional limit of our expressions for the quasinormal frequencies and compare with the previous results. We also determine whether the Dirac field has unstable modes in the D-dimensional Lifshitz spacetime.

A. Lopez-Ortega

2014-07-03T23:59:59.000Z

155

Anharmonic force field and vibrational frequencies of tetrafluoromethane ,,CF4... and tetrafluorosilane ,,SiF4...  

E-Print Network [OSTI]

Anharmonic force field and vibrational frequencies of tetrafluoromethane ,,CF4 1999; accepted 20 October 1999 Accurate quartic anharmonic force fields for CF4 and SiF4 have been field of CF4 is further refined to the experimental data. The symmetrization of the Cartesian basis

Martin, Jan M.L.

156

Electromagnetic interference impact of the proposed emitters for the High Frequency Active Auroral Research Program (HAARP). Interim report  

SciTech Connect (OSTI)

The proposed HAARP emitters at the Gakona (Alaska) preferred site and at the Clear AFS (Alaska) alternative site are the Ionospheric Research Instrument (IRI), the Incoherent Scatter Radar (ISR), and the Vertical Incidence Sounder(VIS). The electromagnetic interference (EMI) impact of those emitters on receiving systems in the vicinity of the sites is estimated in this study. The results are intended for use as an input to the Air Force Environmental Impact Statement as part of the Environmental Impact Analysis Process.

Robertshaw, G.A.; Snyder, A.L.; Weiner, M.M.

1993-05-14T23:59:59.000Z

157

SOLAR WIND ELECTRIC FIELDS IN THE ION CYCLOTRON FREQUENCY RANGE P. J. Kellogg,1  

E-Print Network [OSTI]

SOLAR WIND ELECTRIC FIELDS IN THE ION CYCLOTRON FREQUENCY RANGE P. J. Kellogg,1 S. D. Bale,2 F. S wind in the region near the ion cyclotron frequency of protons, larger than the force due to magnetic fluctuations. They provide sufficient velocity- space diffusion or heating to counteract conservation

California at Berkeley, University of

158

Simulation of Stochastic Fluctuating Wind Field Using the Wave Superposition Method with Random Frequencies  

Science Journals Connector (OSTI)

The wave superposition method is one of the effective methods to simulate the stochastic fluctuating wind field. The simulated wind speed samples with single-indexing frequencies are...T 0 = 2? N/...

D. J. Han; J. J. Luo

2007-01-01T23:59:59.000Z

159

Electromagnetic Geometry  

E-Print Network [OSTI]

We show that Maxwell's electromagnetism can be mapped into the Born-Infeld theory in a curved space-time, which depends only on the electromagnetic field in a specific way. This map is valid for any value of the two lorentz invariants $F$ and $G$ confirming that we have included all possible solutions of Maxwell's equations. Our result seems to show that specifying the dynamics and the space-time structure of a given theory can be viewed merely as a choice of representation to describe the physical system.

M. Novello; F. T. Falciano; E. Goulart

2011-11-08T23:59:59.000Z

160

On the theory of the relativistic motion of a charged particle in the field of intense electromagnetic radiation  

SciTech Connect (OSTI)

Averaged relativistic equations of motion of a charged particle in the field of intense electromagnetic radiation have been obtained in the geometrical optics approximation using the Bogoliubov method. Constraints are determined under which these equations are valid. Oscillating additions to the smoothed dynamical variables of the particle have been found; they are reduced to known expressions in the case of the circularly and linearly polarized plane waves. It has been shown that the expressions for the averaged relativistic force in both cases contain new additional small terms weakening its action. The known difference between the expressions for the ponderomotive force in the cases of circularly and linearly polarized waves has been confirmed.

Milant'ev, V. P., E-mail: vmilantiev@sci.pfu.edu.ru; Castillo, A. J., E-mail: vmilant@mail.ru [Peoples' Friendship University of Russia (Russian Federation)

2013-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Influence of High-Frequency Electric Fields on Equilibrium and Stability of Toroidal Plasmas  

Science Journals Connector (OSTI)

The effect of a high-frequency toroidal electric field on equilibrium and stability of a toroidal plasma is considered. It is shown that for some values of the electric field, one can change the particle orbits considerably with important consequences to diffusion and stability.

M. Dobrowolny and O. P. Pogutse

1970-12-07T23:59:59.000Z

162

Inverse scattering for frequency-scanned full-field optical coherence tomography  

E-Print Network [OSTI]

Inverse scattering for frequency-scanned full-field optical coherence tomography Daniel L. Marks-field optical coherence tomography (OCT) is able to image an entire en face plane of scatterers simulta- neously: 100.3010, 110.4500. 1. INTRODUCTION The capabilities of optical coherence tomography1,2 (OCT

Bhargava, Rohit

163

Field-dependent collision frequency of the two-dimensional driven random Lorentz gas Christoph Dellago*  

E-Print Network [OSTI]

Institute for Theoretical Physics, University of Utrecht, Postbus 80006, Utrecht 3508 TA, The Netherlands-driven, thermostated Lorentz gas the collision frequency increases with the magnitude of the applied field due to long exponents on the applied field strength. These nonanalytic terms can be traced back to logarithmic terms

Dellago, Christoph

164

Interpretation of electromagnetic soundings in the Raft River geothermal  

Open Energy Info (EERE)

Interpretation of electromagnetic soundings in the Raft River geothermal Interpretation of electromagnetic soundings in the Raft River geothermal area, Idaho Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Interpretation of electromagnetic soundings in the Raft River geothermal area, Idaho Details Activities (1) Areas (1) Regions (0) Abstract: An electromagnetic (EM) controlled source survey was conducted in the Raft River Valley, near Malta, Idaho. The purpose of the survey was: to field test U.S. Geological Survey extra-low-frequency (ELF) equipment using a grounded wire source and receiver loop configuration (which is designed to measure the vertical magnetic field (Hz) at the loop center for various frequencies); to present an example of the EM sounding data and interpretations using a previously developed inversion program; and (3) to

165

Electromagnetic Soundings At Raft River Geothermal Area (1977) | Open  

Open Energy Info (EERE)

Electromagnetic Soundings At Raft River Geothermal Area (1977) Electromagnetic Soundings At Raft River Geothermal Area (1977) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Electromagnetic Soundings At Raft River Geothermal Area (1977) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Electromagnetic Sounding Techniques Activity Date 1977 Usefulness not indicated DOE-funding Unknown Exploration Basis The purpose of the survey was: (1) to field test U.S. Geological Survey extra-low-frequency (ELF) equipment using a grounded wire source and receiver loop configuration (which is designed to measure the vertical magnetic field (Hz) at the loop center for various frequencies); (2) to present an example of the EM sounding data and interpretations using a

166

Transient electromagnetic interference in substations  

SciTech Connect (OSTI)

Electromagnetic interference levels on sensitive electronic equipment are quantified experimentally and theoretically in air and gas insulated substations of different voltages. Measurement techniques for recording interference voltages and currents and electric and magnetic fields are reviewed and actual interference data are summarized. Conducted and radiated interference coupling mechanisms and levels in substation control wiring are described using both measurement results and electromagnetic models validated against measurements. The nominal maximum field and control wire interference levels expected in the switchyard and inside the control house from switching operations, faults, and an average lightning strike are estimated using high frequency transient coupling models. Comparisons with standards are made and recommendations given concerning equipment shielding and surge protection.

Wiggins, C.M.; Thomas, D.E.; Nickel, F.S.; Salas, T.M. (BDM International, Inc., Albuquerque, NM (United States)); Wright, S.E. (Electric Power Research Inst., Palo Alto, CA (United States))

1994-10-01T23:59:59.000Z

167

Visualizing electromagnetic fields in laser-produced counter-streaming plasma experiments for collisionless shock laboratory astrophysics  

SciTech Connect (OSTI)

Collisionless shocks are often observed in fast-moving astrophysical plasmas, formed by non-classical viscosity that is believed to originate from collective electromagnetic fields driven by kinetic plasma instabilities. However, the development of small-scale plasma processes into large-scale structures, such as a collisionless shock, is not well understood. It is also unknown to what extent collisionless shocks contain macroscopic fields with a long coherence length. For these reasons, it is valuable to explore collisionless shock formation, including the growth and self-organization of fields, in laboratory plasmas. The experimental results presented here show at a glance with proton imaging how macroscopic fields can emerge from a system of supersonic counter-streaming plasmas produced at the OMEGA EP laser. Interpretation of these results, plans for additional measurements, and the difficulty of achieving truly collisionless conditions are discussed. Future experiments at the National Ignition Facility are expected to create fully formed collisionless shocks in plasmas with no pre-imposed magnetic field.

Kugland, N. L.; Ross, J. S.; Glenzer, S. H.; Huntington, C.; Martinez, D.; Plechaty, C.; Remington, B. A.; Ryutov, D. D.; Park, H.-S. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Chang, P.-Y.; Fiksel, G.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14636 (United States)] [Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14636 (United States); Drake, R. P.; Grosskopf, M.; Kuranz, C. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Gregori, G.; Meinecke, J.; Reville, B. [Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)] [Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Koenig, M.; Pelka, A. [Laboratoire pour l'Utilisation des Lasers Intenses (LULI), cole Polytechnique-Univ, Paris VI, 91128 Palaiseau (France)] [Laboratoire pour l'Utilisation des Lasers Intenses (LULI), cole Polytechnique-Univ, Paris VI, 91128 Palaiseau (France); and others

2013-05-15T23:59:59.000Z

168

Noninvasive valve monitor using constant magnetic and/or DC electromagnetic field  

DOE Patents [OSTI]

One or more sources of steady magnetic field are carefully located on the outside of a valve body. The constant magnetic field is transmitted into the valve body and valve internals. A magnetic field detector carefully located on the outside of the valve body detects the intensity of the magnetic field at its location. As the position of a valve internal part is changed, there is an alteration in the magnetic field in the valve, and a consequent change in the detected magnetic field. Changes in the detected signal provide an indication of the position and motion of the valve internals.

Casada, D.A.; Haynes, H.D.

1993-08-17T23:59:59.000Z

169

Self-Duality in Nonlinear Electromagnetism  

E-Print Network [OSTI]

We discuss duality invariant interactions between electromagnetic fields and matter. The case of scalar fields is treated in some detail.

Mary K. Gaillard; Bruno Zumino

1997-05-28T23:59:59.000Z

170

Linked and knotted beams of light, conservation of helicity and the flow of null electromagnetic fields  

E-Print Network [OSTI]

Maxwell's equations allow for some remarkable solutions consisting of pulsed beams of light which have linked and knotted field lines. The preservation of the topological structure of the field lines in these solutions has previously been ascribed to the fact that the electric and magnetic helicity, a measure of the degree of linking and knotting between field lines, are conserved. Here we show that the elegant evolution of the field is due to the stricter condition that the electric and magnetic fields be everywhere orthogonal. The field lines then satisfy a `frozen field' condition and evolve as if they were unbreakable filaments embedded in a fluid. The preservation of the orthogonality of the electric and magnetic field lines is guaranteed for null, shear-free fields such as the ones considered here by a theorem of Robinson. We calculate the flow field of a particular solution and find it to have the form of a Hopf fibration moving at the speed of light in a direction opposite to the propagation of the pulsed light beam, a familiar structure in this type of solution. The difference between smooth evolution of individual field lines and conservation of electric and magnetic helicity is illustrated by considering a further example in which the helicities are conserved, but the field lines are not everywhere orthogonal. The field line configuration at time t=0 corresponds to a nested family of torus knots but unravels upon evolution.

William T. M. Irvine

2011-10-25T23:59:59.000Z

171

Balloon observations of ultra-low-frequency waves in the electric field above the South Pole  

SciTech Connect (OSTI)

The physics of ultra-low-frequency waves in the magnetosphere, near the cusp and in the polar cap, is important because this region is one where ultra-low-frequency wave energy from the magnetopause can most easily enter the magnetosphere. During the 1985-1986 South Pole balloon campaign, eight stratospheric balloon payloads were launched from Amundsen-Scott Station, South Geographic Pole, Antarctica, to record data on ultra-low-frequency waves. The payloads were instrumented with three-axis double-probe electric field detectors and X-ray scintillation counters. This paper concentrates on the third flight of this series, which was launched at 2205 universal time on 21 December 1985. Good data were received from the payload until the transmitter failed at 0342 universal time on 22 December. During most of the four hours that the balloon was afloat, an intense ultra-low-frequency wave event was in progress. The electric-field data from this period have been examined in detail and compared with magnetic field data, obtained with ground-based fluxgate and induction magnetometers to determine the characteristics of the waves. After float was reached, the electric-field data in figure 1 show large-amplitude, quasi-periodic fluctuations suggesting the presence of intense ultra-low-frequency wave activity. In conclusion, the electric-field signature observed from flight 3 appears to have been essentially an electrostatic event or possibly a short-wavelength hydromagnetic wave with a varying and interesting polarization character. The authors are continuing the analysis of the data to determine the source of the observed ultra-low-frequency waves.

Liao, B.; Benbrrook, J.R.; Bering E.A. III; Byrne, G.J.; Theall, J.R. (Univ. of Houston, TX (USA))

1988-01-01T23:59:59.000Z

172

Fast Convergence Algorithm for Earthquake Prediction Using Electromagnetic Fields Excited by SLF/ELF Horizontal Magnetic Dipole and Schumann Resonance  

Science Journals Connector (OSTI)

In order to estimate where the electromagnetic radiation associated with the seismic activity comes from, the propagation characteristics of the SLF/ELF electromagnetic waves on the ground should ... algorithm. A...

Yuan-xin Wang; Zhen-wei Zhao; Zhen-sen Wu

2014-07-01T23:59:59.000Z

173

Lagrangian Formulation of Relativistic Particle Average Motion in a Laser Field of Arbitrary Intensity  

SciTech Connect (OSTI)

The Lagrangian and Hamiltonian functions describing average motion of a relativistic particle under the action of intensive high-frequency electromagnetic radiation are obtained. In weak, low-frequency background fields, such a particle on average drifts with an effective, relativistically invariant mass, which depends on the intensity of the electromagnetic field.

I.Y. Dodin; N.J. Fisch; G.M. Fraiman

2003-02-06T23:59:59.000Z

174

Sensitivity of controlled-source electromagnetic fields in planarly layered media  

Science Journals Connector (OSTI)

......extensions for more general anisotropic conductivity. Although this...Electric dipole fields over an anisotropic seaoor: theory and application...fields in planarly layered anisotropic media,Geophys. J. Int...geothermal reservoirs, and gas shales using controlled-source......

R. Streich; M. Becken

2011-11-01T23:59:59.000Z

175

Lightning strikes to tall objects: Currents inferred from far electromagnetic fields versus directly measured currents  

E-Print Network [OSTI]

-field-to-current conversion factors for lightning strikes to tall objects for (1) the initial peak current at the object top. These far-field-to-current conversion factors are needed for proper interpretation of peak currents reported-field-to-current conversion factor for lightning strikes to flat ground based on the transmission line model and (b

Florida, University of

176

Electromagnetic WavesElectromagnetic Waves In this chapter we will review selected properties of electromagnetic waves since  

E-Print Network [OSTI]

Electromagnetic WavesElectromagnetic Waves In this chapter we will review selected properties of electromagnetic waves since radar involves the transmission, propagation and scattering of EM waves by various is the electrostatic force between two point charges. #12;Electromagnetic WavesElectromagnetic Waves Electric fields

Rutledge, Steven

177

Emerging issues in extremely-low-frequency electric and magnetic field health research  

SciTech Connect (OSTI)

Concern has increased over potential consequences of exposure to electric and magnetic fields of extremely low frequency (0-100 Hz), particularly from power transmission and distribution. Also at issue are electrical environments in homes and workplaces. Until recently, research focused on the electric, rather than the magnetic, field; now, both are under extensive investigation. A review of research to date indicates the following: Electric and magnetic fields can produce effects in vitro, with the locus of field interaction believed to be at the cell membrane. Chronic in vivo electric field exposure fails to produce effects except in behavior, neurophysiology, endocrinology, and, possibly, fetal development. The extrapolation of these animal data to humans requires further research. The epidemiological literature has, in some cases, reported an association between increased cancer rates and putative field exposure. Exposure assessments indicate that, in all likelihood, human exposures to 60-Hz electric fields of the magnitudes found under transmission lines are very infrequent; assessments are continuing to characterize exposure to 60-Hz magnetic fields and to measure the field frequency spectra found in residential and workplace settings. The public health issues emerging from this research focus on fetal development and on the initiation or promotion of cancer. It is critical to reduce existing uncertainties in order to enable valid risk assessment.

Kavet, R.I.; Banks, R.S.

1986-04-01T23:59:59.000Z

178

Emerging issues in extremely-low-frequency electric and magnetic field health research  

Science Journals Connector (OSTI)

Concern has increased over potential consequences of exposure to electric and magnetic fields of extremely low frequency (0100 Hz), particularly from power transmission and distribution. Also at issue are electrical environments in homes and workplaces. Until recently, research focused on the electric, rather than the magnetic, field; now, both are under extensive investigation. A review of research to date indicates the following: (1) Electric and magnetic fields can produce effects in vitro, with the locus of field interaction believed to be at the cell membrane. (2) Chronic in vivo electric field exposure fails to produce effects except in behavior, neurophysiology, endocrinology, and, possibly, fetal development. The extrapolation of these animal data to humans requires further research. (3) The epidemiological literature has, in some cases, reported an association between increased cancer rates and putative field exposure. (4) Exposure assessments indicate that, in all likelihood, human exposures to 60-Hz electric fields of the magnitudes found under transmission lines are very infrequent; assessments are continuing to characterize exposure to 60-Hz magnetic fields and to measure the field frequency spectra found in residential and workplace settings. The public health issues emerging from this research focus on fetal development and on the initiation or promotion of cancer. It is critical to reduce existing uncertainties in order to enable valid risk assessment.

Robert I. Kavet; Robert S. Banks

1986-01-01T23:59:59.000Z

179

ION HEATING WITH RF FIELDS NEAR THE ION CYCLOTRON FREQUENCY J. D. Barter, J. C. Sprott  

E-Print Network [OSTI]

ION HEATING WITH RF FIELDS NEAR THE ION CYCLOTRON FREQUENCY by J. D. Barter, J. C. Sprott November. Our experiments of the past year, however, indicate that ion cyclotron resonance heating transmitted without consent of the author and major professor. #12;For several years we have been heating ions

Sprott, Julien Clinton

180

PINEAL MELATONIN LEVEL DISRUPTION IN HUMANS DUE TO ELECTROMAGNETIC FIELDS AND ICNIRP LIMITS  

E-Print Network [OSTI]

, thousands of well- documented publications have reported melatonin as a naturally occurring free to power-frequency (50 or 60 Hz) EMFs is unavoidable. Melatonin is a natural hormone produced by pineal Committee of Non-Ionizing Radiation Protection (ICNIRP) limit and also with the existing experimental

Halgamuge, Malka N.

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Project no. 516369 Electromagnetic compatibility between rolling stock and  

E-Print Network [OSTI]

to anything in that environment. Electromagnetic interference (EMI): Degradation of the performance compatibility EMI Electromagnetic interference ETSI European Telecommunications Standards Institute FM Frequency

Paris-Sud XI, Université de

182

On the efficiency of electrical submersible pumps equipped with variable frequency drives: A field study  

SciTech Connect (OSTI)

A field study was conducted on 18 electrical-submersible-pump- (ESP-) equipped wells operating in the Williston basin. Fifteen of these wells were run with variable frequency drives (VFD`s). The purpose of the study was to determine the efficiency and operating characteristics of ESP`s operating with VFD`s and compare them to those without. Voltage, current, power, and frequency were measured at the drive input, the drive output, and ESP input. Production data were recorded and power and efficiency were calculated at all measurement locations and compared to published data.

Patterson, M.M. [Patterson (Maurice M.), Hemphill, TX (United States)

1996-02-01T23:59:59.000Z

183

Experimental investigations of the interaction between the ELF Earth electromagnetic fields and astrophysical processes  

Science Journals Connector (OSTI)

Investigations of the moon and solar tides and their interaction with the electric field of the atmospheric boundary layer are possible both by means of using big data files and by using a method of spaced reception.

L. V. Grunskaya; V. A. Efimov; V. V. Isakevich; A. A. Zakirov

2010-01-01T23:59:59.000Z

184

Observations of Electromagnetic Fields and Plasma Flow in Hohlraums with Proton Radiography  

E-Print Network [OSTI]

We report on the first proton radiography of laser-irradiated hohlraums. This experiment, with vacuum gold (Au) hohlraums, resulted in observations of self-generated magnetic fields with peak values ~10[superscript 6]??G. ...

Betti, R.

185

Fiber optic probe of free electron evanescent fields in the optical frequency range  

SciTech Connect (OSTI)

We introduce an optical fiber platform which can be used to interrogate proximity interactions between free-electron evanescent fields and photonic nanostructures at optical frequencies in a manner similar to that in which optical evanescent fields are sampled using nanoscale aperture probes in scanning near-field microscopy. Conically profiled optical fiber tips functionalized with nano-gratings are employed to couple electron evanescent fields to light via the Smith-Purcell effect. We demonstrate the interrogation of medium energy (3050?keV) electron fields with a lateral resolution of a few micrometers via the generation and detection of visible/UV radiation in the 700300?nm (free-space) wavelength range.

So, Jin-Kyu, E-mail: js1m10@orc.soton.ac.uk; MacDonald, Kevin F. [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Zheludev, Nikolay I. [Optoelectronics Research Centre and Centre for Photonic Metamaterials, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Centre for Disruptive Photonic Technologies, Nanyang Technological University, Singapore 637371 (Singapore)

2014-05-19T23:59:59.000Z

186

Electromagnetically induced invisibility cloaking  

E-Print Network [OSTI]

Invisibility cloaking imposes strict conditions on the refractive index profiles of cloaking media that must be satisfied to successfully hide an object. The first experimental demonstrations of cloaking used artificial metamaterials to respond to this challenge. In this work we show how a much simpler technique of electromagnetically induced transparency can be used to achieve a partial, {\\it carpet} cloaking at optical frequencies in atomic vapours or solids. To generate a desired combination of low absorption with strong modifications of the refractive index, we use chiral media with an induced magneto-electrical cross-coupling. We demonstrate that high-contrast positive refractive indices can be attained by fine tuning the material with a gradient magnetic field and calculate the parameters required to construct a carpet cloak.

Darran F. Milne; Natalia Korolkova

2012-06-18T23:59:59.000Z

187

Exposure to extremely low frequency magnetic fields among working women and homemakers  

Science Journals Connector (OSTI)

Given concerns with potential health effects of exposure to magnetic fields, the goal of this study was to examine the magnitude and sources of occupational and residential exposure to extremely low frequency (primarily 60 Hz) magnetic fields among women. Exposure to 60 Hz magnetic fields was surveyed among cases and controls recruited for a study of breast cancer in 25 counties in North Carolina. The 273 women who participated wore an integrating personal magnetic-field exposure meter (AMEX 3-D) that measured their time-weighted average (TWA) exposure. A questionnaire was administered to determine the duration and frequency of electric appliance and machinery use. The geometric mean (GM) of the TWA exposure for employed women was 0.138 ?T (range 0.0223.636 ?T) and for homemakers 0.113 ?T (range 0.0220.403 ?T). Women working in manufacturing and industrial facilities had the highest exposure (GM 0.265 ?T, range 0.0543.436 ?T), while nurses and health technicians (GM 0.134 ?T, range 0.0320.285 ?T) and teachers and school administrators (GM 0.099 ?T, range 0.0350.673 ?T) had the lowest exposures. Job titles, unless very limited in scope and/or environment, self-reported information about equipment use, potential exposure sources, time, and distance were not good predictors of magnetic-field exposure. Furthermore, the results show that occupations previously observed to have increased risk of breast cancer, such as teachers, nurses, administrative support, and housewives, did not have elevated average magnetic field exposures. Therefore, it is questionable whether exposure to power frequency magnetic fields is the cause of the increased breast cancer risk seen in these occupations.

Allison L McCurdy; Louis Wijnberg; Dana Loomis; David Savitz; Leena A Nylander-French

2001-01-01T23:59:59.000Z

188

Retarding field analyzer for ion energy distribution measurements at a radio-frequency biased electrode  

SciTech Connect (OSTI)

A retarding field energy analyzer designed to measure ion energy distributions impacting a radio-frequency biased electrode in a plasma discharge is examined. The analyzer is compact so that the need for differential pumping is avoided. The analyzer is designed to sit on the electrode surface, in place of the substrate, and the signal cables are fed out through the reactor side port. This prevents the need for modifications to the rf electrode--as is normally the case for analyzers built into such electrodes. The capabilities of the analyzer are demonstrated through experiments with various electrode bias conditions in an inductively coupled plasma reactor. The electrode is initially grounded and the measured distributions are validated with the Langmuir probe measurements of the plasma potential. Ion energy distributions are then given for various rf bias voltage levels, discharge pressures, rf bias frequencies - 500 kHz to 30 MHz, and rf bias waveforms - sinusoidal, square, and dual frequency.

Gahan, D.; Hopkins, M. B. [National Centre for Plasma Science and Technology, Dublin City University, Glasnevin, Dublin 9 (Ireland); Dolinaj, B. [Impedans Ltd., Invent Centre, Dublin City University, Glasnevin, Dublin 9 (Ireland)

2008-03-15T23:59:59.000Z

189

PHYSICS 416. Electromagnetism. Lecturer: Tim Gorringe.  

E-Print Network [OSTI]

PHYSICS 416. Electromagnetism. Lecturer: Tim Gorringe. Office: CP 273. Phone: 257-8740. Textbook: Electromagnetic Fields, R. Wangsness, 2nd Ed. Web page www.pa.uky.edu/gorringe/phy416/index.html Class hours: MWF-semester sequence on electromagnetic theory. 1 416/417 Course Objectives. The electromagnetic field binds electrons

MacAdam, Keith

190

PHYSICS 417. Electromagnetism. Lecturer: Tim Gorringe.  

E-Print Network [OSTI]

PHYSICS 417. Electromagnetism. Lecturer: Tim Gorringe. Office: CP273. Phone: 257-8740. Textbook: Electromagnetic Fields, R. Wangsness, 2nd Ed. Web page www.pa.uky.edu/gorringe/phy417/index.html Class hours: MWF-semester sequence on electromagnetic theory. 1 Course Objectives. The electromagnetic field binds electrons

MacAdam, Keith

191

Electromagnetic structure of pion  

SciTech Connect (OSTI)

In this work, we analyze the electromagnetic structure of the pion, an elementary particle composed by a quark-antiquark bound state, by considering the calculation of its electromagnetic radius and its electromagnetic form factor in low and intermediate energy range. Such observables are determined by means of a theoretical model that takes into account the constituent quark and antiquark of the pion, in the formalism of the light-front field theory. In particular, it is considered a nonsymmetrical vertex for such a model, in which we have calculated the electromagnetic form factor of the pion in an optimized way, by varying its regulator mass, so that we can obtain the best value for the pion electromagnetic radius when compared with the experimental one. The theoretical calculations are also compared with the most recent experimental data involving the pion electromagnetic form factor and the results show very good agreement.

Mello, Clayton S.; Cruz Filho, Jose P.; Da Silva, Edson O.; El-Bennich, Bruno; De Melo, J. P.; Filho, Victo S. [Laboratorio de Fisica Teorica e Computacional (LFTC), Universidade Cruzeiro do Sul, 01506-000, Sao Paulo (Brazil)

2013-03-25T23:59:59.000Z

192

Characterization of the reactive flow field dynamics in a gas turbine injector using high frequency PIV  

E-Print Network [OSTI]

The present work details the analysis of the aerodynamics of an experimental swirl stabilized burner representative of gas turbine combustors. This analysis is carried out using High Frequency PIV (HFPIV) measurements in a reactive situation. While this information is usually available at a rather low rate, temporally resolved PIV measurements are necessary to better understand highly turbulent swirled flows, which are unsteady by nature. Thanks to recent technical improvements, a PIV system working at 12 kHz has been developed to study this experimental combustor flow field. Statistical quantities of the burner are first obtained and analyzed, and the measurement quality is checked, then a temporal analysis of the velocity field is carried out, indicating that large coherent structures periodically appear in the combustion chamber. The frequency of these structures is very close to the quarter wave mode of the chamber, giving a possible explanation for combustion instability coupling.

Barbosa, Sverine; Ducruix, Sbastien

2008-01-01T23:59:59.000Z

193

Progress In Electromagnetics Research B, Vol. 13, 120, 2009 MAGNETIC FIELD PRODUCED BY A TILE  

E-Print Network [OSTI]

by permanent magnets is very useful for optimizing alternate magnet structures or magnetic couplings PERMANENT MAGNET WHOSE POLARIZATION IS BOTH UNIFORM AND TANGENTIAL R. Ravaud, G. Lemarquand, V. Lemarquand field produced by a tile permanent magnet whose polarization is both tangential and uniform

Paris-Sud XI, Université de

194

EEL 4461 Antenna Systems 1. Catalog Description (3 credits) Electromagnetic field theory and its application to  

E-Print Network [OSTI]

-field radiation RF propagation, ground effect, weather effect, RF safety Dipole antennas Loop antennas Microstrip minutes each 10. Meeting Location ­ 202 NEB 11. Material and Supply Fees - None 12. Textbooks and Software of antenna Introduction of different types of antennas and their applications Antenna radiation pattern

Fang, Yuguang "Michael"

195

Measurement and analysis of electromagnetic fields from trams, trains and hybrid cars  

Science Journals Connector (OSTI)

......vital to limit energy consumption at the same time as...energy is supplied as fuel and the internal combustion engine (ICE) uses a motor...emissions and have better fuel economy than conventional...field exposure when engines move at a higher speed......

Malka N. Halgamuge; Chathurika D. Abeyrathne; Priyan Mendis

2010-10-01T23:59:59.000Z

196

Energy Down Conversion between Classical Electromagnetic Fields via a Quantum Mechanical SQUID Ring  

E-Print Network [OSTI]

We consider the interaction of a quantum mechanical SQUID ring with a classical resonator (a parallel $LC$ tank circuit). In our model we assume that the evolution of the ring maintains its quantum mechanical nature, even though the circuit to which it is coupled is treated classically. We show that when the SQUID ring is driven by a classical monochromatic microwave source, energy can be transferred between this input and the tank circuit, even when the frequency ratio between them is very large. Essentially, these calculations deal with the coupling between a single macroscopic quantum object (the SQUID ring) and a classical circuit measurement device where due account is taken of the non-perturbative behaviour of the ring and the concomitant non-linear interaction of the ring with this device.

M. J. Everitt; T. D. Clark; P. B. Stiffell; C. J. Harland; J. F. Ralph

2005-05-16T23:59:59.000Z

197

Electric dipole moment searches: Effect of linear electric field frequency shifts induced in confined gases, II  

E-Print Network [OSTI]

The next generation of particle edm searches will be at such a high sensitivity that it will be possible for the results to be contaminated by a systematic error resulting from the interaction of the motional (E x v/c) magnetic field with stray field gradients. In this paper we extend previous work to present an analytic form for the frequency shift in the case of a rectangular storage vessel and discuss the implications of the result for the neutron edm experiment which will be installed at the SNS (Spallation Neutron Source) by the LANL collaboration

R. Golub; C. M. Swank; S. K. Lamoreaux

2009-06-03T23:59:59.000Z

198

Radio-frequency sheath-plasma interactions with magnetic field tangency points along the sheath surface  

SciTech Connect (OSTI)

Computer simulations of radio-frequency (RF) waves propagating across a two-dimensional (2D) magnetic field into a conducting boundary are described. The boundary condition for the RF fields at the metal surface leads to the formation of an RF sheath, which has previously been studied in one-dimensional models. In this 2D study, it is found that rapid variation of conditions along the sheath surface promote coupling of the incident RF branch (either fast or slow wave) to a short-scale-length sheath-plasma wave (SPW). The SPW propagates along the sheath surface in a particular direction dictated by the orientation of the magnetic field with respect to the surface, and the wave energy in the SPW accumulates near places where the background magnetic field is tangent to the surface.

Kohno, H. [Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, Pennsylvania 18015 (United States)] [Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, Pennsylvania 18015 (United States); Myra, J. R.; D'Ippolito, D. A. [Lodestar Research Corporation, 2400 Central Avenue P-5, Boulder, Colorado 80301 (United States)] [Lodestar Research Corporation, 2400 Central Avenue P-5, Boulder, Colorado 80301 (United States)

2013-08-15T23:59:59.000Z

199

Control of resonant frequency by currents in graphene: Effect of Dirac field on deflection  

SciTech Connect (OSTI)

To construct Lagrangian based on plate theory and tight-binding model, deflection-field coupling to Dirac fermions in graphene can be investigated. As have been known, deflection-induced strain may cause an effect on motion of electron, like a pseudo gauge field. In the work, we will investigate the effect of the Dirac field on the motion of the deflection-field in graphene derived from Lagrangian density. Due to the interaction of the deflection- and Dirac-fields, the current-induced surface-tension up to about 410{sup ?3} N/m in graphene membrane is predicted. This result may lead to controllable resonant frequency by currents in graphene. The high resonant frequency is found to be perfectly linearly controlled by both charge and valley currents. Our work reveals the potential of graphene for application of nano-electro-mechanical device and the physics of interaction of electron and deflection-filed in graphene system is investigated.

Soodchomshom, Bumned, E-mail: Bumned@hotmail.com, E-mail: fscibns@ku.ac.th [Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand)

2014-09-21T23:59:59.000Z

200

Observations of electromagnetic fields and plasma flow in hohlraums with proton radiography  

SciTech Connect (OSTI)

The authors report on the first proton radiography of laser-irradiated hohlraums. This experiment, with vacuum gold (Au) hohlraums, resulted in observations of self-generated electric and magnetic fields. Peak values are {approx} 10{sup 9} V m{sup -1} and {approx} 10{sup 6} gauss. Time-gated radiographs of monoenergetic protons with discrete energies (15.0 and 3.3 MeV) reveal dynamic pictures of field structures and plasma flow. Near the end of the 1-ns laser drive, a stagnating Au plasma ({approx} 10 mg cm{sup -3}) forms at the center of the hohlraum, a consequence of supersonic, radially directed Au jets ({approx} 1000 {micro}m ns{sup -1}, {approx} Mach 4) as laser-driven plasma bubbles approaching one another.

Li, C K; Seguin, F H; Frenje, J A; Petrasso, R D; Amendt, P A; Town, R J; Landen, O L; Rygg, J R; Betti, R; Knauer, J P; Meyerhofer, D D; Soures, J M; Back, C A; Kilkenny, J D; Nikroo, A

2009-01-29T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Third order Lovelock black branes in the presence of a nonlinear electromagnetic field  

E-Print Network [OSTI]

We consider third order Lovelock gravity coupled to an U(1) gauge field for which its Lagrangian is given by a power of Maxwell invariant. In this paper, we present a class of horizon flat rotating black branes and investigate their geometrical properties and the effect of nonlinearity on the solutions. We use some known formulas and methods to calculate thermodynamic and conserved quantities. Finally, we check the satisfaction of the first law of thermodynamics.

Hendi, S H; Mohammadpour, H

2015-01-01T23:59:59.000Z

202

Coupling of electrons to the electromagnetic field in a localized basis  

E-Print Network [OSTI]

, such as materials and molecules, responding to ap- plied fields, such as ultrashort laser pulses.9?19 Our starting point is, of course, the time-dependent Schr?dinger equation, i#1; #1; #1;t #2;#1;x,t#2; = H? #2;#1;x,t#2; , #1;1#2; H? = 1 2m#3;? i#1; #1...; ? qc A#1;x,t#2;#4;2 + U, q = ? e . #1;2#2; Some time ago, Graf and Vogl20 obtained a result, used in Refs. 13?19, which is the time-dependent version of the Peierls substitution: If H0 is the Hamiltonian matrix in a localized basis with no applied...

Allen, Roland E.

2008-01-01T23:59:59.000Z

203

Using wavelet analysis to detect the influence of low frequency magnetic fields on human physiological tremor  

Science Journals Connector (OSTI)

The influence of extremely low frequency magnetic fields (ELF-MFs) on human physiological processes and, in particular, on motor activity is still not established with certainty. Using the wavelet-transform approach, changes in the characteristics of human finger micromovement are studied in the presence of a low intensity MF centred at the level of the head. Different approaches to nonstationary signal analysis involving real as well as complex wavelet functions are considered. We find evidence that ELF-MFs lead to more regular postural tremor and more homogeneous energy distribution.

A N Pavlov; A N Tupitsyn; A Legros; A Beuter; E Mosekilde

2007-01-01T23:59:59.000Z

204

An ultra-capacitor for frequency stability enhancement in small-isolated power systems: Models, simulation and field tests  

Science Journals Connector (OSTI)

Abstract The most relevant issue in operation of isolated power systems is frequency stability. Frequency stability is concerned with the ability of generators to supply the loads at an acceptable frequency after a disturbance. Frequency stability is governed by the kinetic energy stored in the generator-prime mover rotating masses and the prime mover frequency primary regulation. If frequency excursions are not within +/?2.5Hz range, cascade tripping of the remaining generators can occur because of generator over/under frequency protections tripping. Energy storage systems can contribute to frequency stability enhancement if their discharging is governed by a frequency controller. Endesa is leading a research project on testing the state of the art of energy storage systems for several applications (peak-shaving, voltage control, frequency control) in several isolated power systems of the Canary Islands. Several applications are being investigated. One of them consists on the application of a 4MW5s ultracapacitor (UC) for frequency stability enhancement of the La Palma power system. This paper reports the dynamic model developed for time domain simulation and controller design of frequency stability, and field tests undertaken to validate models and the controller settings. A simple but still accurate model is presented. The proposed model takes into account the UCs state of charge (SoC) and it represents the dynamics of the power electronics by means of a non-linear first-order model. The frequency control consists of droop control and inertia emulation. Ramp rate limits, power limits and SoC are also taken into account in the frequency control. In comparison with the recorded field tests, the proposed model is able to accurately represent the response of the UC for the purpose of frequency stability analysis.

I. Egido; L. Sigrist; E. Lobato; L. Rouco; A. Barrado

2015-01-01T23:59:59.000Z

205

Electromagnetic induction in accelerated conductors  

Science Journals Connector (OSTI)

Boundary conditions are derived for the interfaces of a conductor moving across an external magnetic field in an ambient medium (vacuum or nonconductor), which consider the emission of electromagnetic waves from the conductor surface as a result of electromagnetic induction. These boundary conditions are applied to the initial-boundary-value problem for the electromagnetic induction in a conducting slab, which is accelerated across a homogeneous magnetic field to a nonrelativistic velocity. Fourier-series solutions are presented for the transient electromagnetic fields in the moving conductor and the discontinuous electromagnetic waves in the ambient space. It is shown that the transient electromagnetic fields inside and outside the conductor are due to two mechanisms, i.e., "velocity induction" (ordinary induction) and "acceleration induction" [dv?(t)dt?0?]. The latter result cannot be explained by means of the Lorentz transformation, which is valid only for constant conductor velocities (inertial frames).

H. E. Wilhelm

1982-06-01T23:59:59.000Z

206

Coronary heart diseases: Assessment of risk associated with work exposure to ultralow-frequency magnetic fields  

SciTech Connect (OSTI)

The present analysis was stimulated by previous findings on the possible influence of natural ultralow-frequency (ULF; 0.001--10 Hz) geomagnetic field variations on the cardiovascular system and indications of an effect of man-made ULF magnetic fields on the rate of myocardial infarction. In the present study, the authors considered the occupational health hazards of the strongest ULF magnetic fields in densely populated urban areas. Measurements of ULF magnetic field fluctuations produced by trains powered by DC electricity were performed by means of a computer-based, highly sensitive, three-component magnetometer. The authors found that the magnitude of magnetic field pulses inside the driver`s cab of electric locomotives (ELs) could be {ge} 280 {micro}T in the vertical component, and, in the driver`s compartment of electric motor unit (EMU) trains, they were approximately 50 and 35 {micro}T, respectively. The authors have investigated the relationships between the occupational exposure to ULF magnetic field fluctuations produced by electric trains and cardiovascular diseases (CVDs) among railroad workers in the former Soviet Union. They have analyzed medical statistical data for a period of 3 years for approximately 45,000 railroad workers and 4,000 engine drivers. The authors have also analyzed 3 years of morbidity data for three subgroups of engine drivers ({approximately} 4,000 in each group) operating different types of trains. They find that EL drivers have a twofold increase in risk (2.00 {+-} 0.27) of coronary heart diseases (CHDs) compared with EMU drivers. Because the analysis of major CVDs shows that the examined subpopulations of drivers can be considered to have had equal exposure to all known risk factors, the elevated CHD risk among El drivers could be attributed to the increased occupational exposure to ULF magnetic fields.

Ptitsyna, N.G.; Kopytenko, Y.A.; Tyasto, M.I.; Kopytenko, E.A.; Voronov, P.M.; Zaitsev, D.B. [Inst. of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation, St. Petersburg (Russian Federation)] [Inst. of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation, St. Petersburg (Russian Federation); Villoresi, G. [CNR, Frascati (Italy). Inst. di Fisica Spazio Interplanetario] [CNR, Frascati (Italy). Inst. di Fisica Spazio Interplanetario; Kudrin, V.A. [Inst. of Railroad Workers` Hygiene, Moscow (Russian Federation)] [Inst. of Railroad Workers` Hygiene, Moscow (Russian Federation); Iucci, N. [Terza Univ. di Roma, Rome (Italy). Dipt. di Fisica E. Amaldi] [Terza Univ. di Roma, Rome (Italy). Dipt. di Fisica E. Amaldi

1996-12-31T23:59:59.000Z

207

Enhanced stability of a dewetting thin liquid film in a single-frequency vibration field S. Shklyaev,1  

E-Print Network [OSTI]

amplitude equation for the averaged film thickness. We show that there exists a window in the frequencyEnhanced stability of a dewetting thin liquid film in a single-frequency vibration field S; published 31 March 2008 Dynamics of a thin dewetting liquid film on a vertically oscillating substrate

Khenner, Mikhail

208

Everyday exposure to power frequency magnetic fields and associations with non-specific physical symptoms  

Science Journals Connector (OSTI)

Abstract The aim of this study was to investigate the association between exposure to extremely low frequency magnetic fields (ELF MF), or power frequency fields, and non-specific physical symptoms (NSPS). In a cross-sectional study, personal exposure to ELF MF was measured for 99 adults selected in and around Amsterdam, the Netherlands in 20092010. They were scored on 16 NSPS. As a cut-off point for the individual 24-htime weighted average exposure the 80-percentile (0.09?T) was chosen. As only one man scored moderately high on the somatisation scale against nine women, we decided to proceed analyses only with the 48 women. The crude odds ratio (OR) for women was 8.50 (CI 95%: 1.7346.75), suggesting that for women environmental exposure to ELF MF is associated with an increased score on NSPS. As this is an exploratory cross-sectional study in a relatively small sample, no conclusions regarding causality can be drawn.

John F.B. Bolte; Christos Baliatsas; Tessa Eikelboom; Irene van Kamp

2015-01-01T23:59:59.000Z

209

Nonlocal theory of electromagnetic wave decay into two electromagnetic waves in a rippled density plasma channel  

SciTech Connect (OSTI)

Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.

Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)

2012-12-15T23:59:59.000Z

210

Definition: Ground Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Ground Electromagnetic Techniques Jump to: navigation, search Dictionary.png Ground Electromagnetic Techniques Ground electromagnetic techniques measure electromagnetic fields in order to determine subsurface electrical resistivity with the earth surface as the observation point.[1] View on Wikipedia Wikipedia Definition The electromagnetic force is one of the four fundamental interactions in nature, the other three being the strong interaction, the weak interaction, and gravitation. This force is described by electromagnetic fields, and has innumerable physical instances including the interaction of electrically charged particles and the interaction of uncharged magnetic force fields with electrical conductors. The word

211

EXPOSURE ESTIMATES BASED ON BROADBAND ELF MAGNETIC FIELD MEASUREMENTS VERSUS THE ICNIRP MULTIPLE FREQUENCY RULE  

Science Journals Connector (OSTI)

......absorption of energy during exposure...extremely low-frequency (ELF) magnetic...data logging and storage and performs FFT...responding to a sum of frequencies by a sum of independent responses to each individual frequency(23). This......

Jess M. Paniagua; Montaa Rufo; Antonio Jimnez; Fernando T. Pachn; Julin Carrero

2014-05-01T23:59:59.000Z

212

The interaction of radio frequency electromagnetic fields with atmospheric water droplets and application to aircraft ice prevention  

E-Print Network [OSTI]

In this work the physics of advanced microwave anti-icing systems, which pre-heat impinging supercooled water droplets prior to impact, is studied by means of a computer simulation and is found to be feasible. In order to ...

Hansman, Robert John

1982-01-01T23:59:59.000Z

213

Beam dynamics studies for transverse electromagnetic mode type rf deflectors  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We have performed three-dimensional simulations of beam dynamics for transverse electromagnetic mode (TEM) type rf deflectors: normal and superconducting. The compact size of these cavities as compared to the conventional TM110 type structures is more attractive particularly at low frequency. Highly concentrated electromagnetic fields between the parallel bars provide strong electrical stability to the beam for any mechanical disturbance. An array of six 2-cell normal conducting cavities or a single cell superconducting structure is enough to produce the required vertical displacement at the target point. Both the normal and superconducting structures show very small emittance dilution due to the vertical kick of the beam.

Ahmed, Shahid; Krafft, Geoffrey A.; Deitrick, Kirsten; De Silva, Subashini U.; Delayen, Jean R.; Spata, Mike; Tiefenback, Michael; Hofler, Alicia; Beard, Kevin

2012-02-01T23:59:59.000Z

214

Statistics of the electromagnetic response of a chaotic reverberation chamber  

E-Print Network [OSTI]

This article presents a study of the electromagnetic response of a chaotic reverberation chamber (RC) in the presence of losses. By means of simulations and of experiments, the fluctuations in the maxima of the field obtained in a conventional mode-stirred RC are compared with those in a chaotic RC in the neighborhood of the Lowest Useable Frequency (LUF). The present work illustrates that the universal spectral and spatial statistical properties of chaotic RCs allow to meet more adequately the criteria required by the Standard IEC 61000-4-21 to perform tests of electromagnetic compatibility.

J. -B. Gros; U. Kuhl; O. Legrand; F. Mortessagne; O. Picon; E. Richalot

2014-09-20T23:59:59.000Z

215

611: Electromagnetic Theory Problem Sheet 5  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 5 (1a) Show that the energy-momentum tensor for the electromagnetic field is tracefree, i.e. Tµ µ = 0. What would happen, in a spacetime dimension d = 4? (Assume) Show that the energy-momentum tensor for the electromagnetic field can be written as Tµ = 1 8 (Fµ F

Pope, Christopher

216

Why Study Electromagnetics: The First Unit in an Undergraduate Electromagnetics Course  

E-Print Network [OSTI]

1 Why Study Electromagnetics: The First Unit in an Undergraduate Electromagnetics Course Allen unification of electric and magnetic fields predicting electromagnetic wave phenomena which Nobel Laureate: "Of what relevance is the study of electromagnetics to our modern society?" The goal of this unit

Taflove, Allen

217

Comparison of coupling of humans to electric and magnetic fields with frequencies between 100 Hz and 100 kHz  

SciTech Connect (OSTI)

Recent laboratory and epidemiological results have stimulated interest in the hypothesis that human beings may exhibit biological responses to magnetic and/or electric field transients with frequencies in the range between 100 Hz and 100 kHz. Much can be learned about the response of a system to a transient stimulation by understanding its response to sinusoidal disturbances over the entire frequency range of interest. Thus, the main effort of this paper was to compare the strengths of the electric fields induced in homogeneous ellipsoidal models by uniform 100 Hz through 100 kHz electric and magnetic fields. Over this frequency range, external electric fields of about 25--2,000 V/m (depending primarily on the orientation of the body relative to the field) are required to induce electric fields inside models of adults and children that are similar in strength to those induced by an external 1 {mu}T magnetic field. Additional analysis indicates that electric fields induced by uniform external electric and magnetic fields and by the nonuniform electric and magnetic fields produced by idealized point sources will not differ by more than a factor of two until the sources are brought close to the body. Published data on electric and magnetic field transients in residential environments indicate that, for most field orientations, the magnetic component will induce stronger electric fields inside adults and children than the electric component. This conclusion is also true for the currents induced in humans by typical levels of 60 Hz electric and magnetic fields in US residences.

Kaune, W.T. [EM Factors, Richland, WA (United States)] [EM Factors, Richland, WA (United States); Guttman, J.L. [Enertech Consultants, Campbell, CA (United States)] [Enertech Consultants, Campbell, CA (United States); Kavet, R. [Electric Power Research Inst., Palo Alto, CA (United States)] [Electric Power Research Inst., Palo Alto, CA (United States)

1997-03-01T23:59:59.000Z

218

Investigation of the sources of residential power frequency magnetic field exposure in the  

Science Journals Connector (OSTI)

There is an unexplained association between exposure to the magnetic fields arising from the supply and use of electricity, and increase in risk of childhood leukaemia. The UK Childhood Cancer Study (UKCCS) provides a large and unique source of information on residential magnetic field exposure in the UK. The purpose of this supplementary study was to investigate a sample of UKCCS homes in order to identify the particular sources that contribute to elevated time-averaged exposure. In all, 196 homes have been investigated, 102 with exposures estimated on the basis of the original study to be above 0.2??T, and 21 higher than 0.4??T, a threshold above which a raised risk has been observed. First, surveys were carried out outside the property boundaries of all 196 study homes, and then, where informed consent had been obtained, assessments were conducted inside the properties of 19 homes. The study found that low-voltage (LV) sources associated with the final electricity supply accounted together for 77% of exposures above 0.2??T, and 57% of those above 0.4??T. Most of these exposures were linked to net currents in circuits inside and/or around the home. High-voltage (HV) sources, including the HV overhead power lines that are the focus of public concern, accounted for 23% of the exposures above 0.2??T, and 43% of those above 0.4??T. Public health interest has focused on the consideration of precautionary measures that would reduce exposure to power frequency magnetic fields. Our study provides a basis for considering the options for exposure mitigation in the UK. For instance, in elevated-exposure homes where net currents are higher than usual, if it is possible to reduce the net currents, then the exposure could be reduced for a sizeable proportion of these homes. Further investigations would be necessary to determine whether this is feasible.

M P Maslanyj; T J Mee; D C Renew; J Simpson; P Ansell; S G Allen; E Roman

2007-01-01T23:59:59.000Z

219

Quaternion Gravi-Electromagnetism  

E-Print Network [OSTI]

Defining the generalized charge, potential, current and generalized fields as complex quantities where real and imaginary parts represent gravitation and electromagnetism respectively, corresponding field equation, equation of motion and other quantum equations are derived in manifestly covariant manner. It has been shown that the field equations are invariant under Lorentz as well as duality transformations. It has been shown that the quaternionic formulation presented here remains invariant under quaternion transformations.

A. S. Rawat; O. P. S. Negi

2011-07-05T23:59:59.000Z

220

Electromagnetic Radiation in Accelerated Systems  

Science Journals Connector (OSTI)

A generally covariant set of electromagnetic field equations and associated constitutive relations is developed to deal with electromagnetic radiation in arbitrarily moving media. The equations are sufficiently general to include dispersive as well as nonisotropic media. Several special cases are investigated to illustrate the method and to demonstrate the consistency of the formulation.

J. L. Anderson and J. W. Ryon

1969-05-25T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

High-Frequency Conductivity of a Plasma in Quasi-Equilibrium. II. Effect of a Uniform Magnetic Field  

Science Journals Connector (OSTI)

A general expression for high-frequency conductivity is derived to include the effect of an external magnetic field. The limit of large ion mass is also discussed. For the special case that the unperturbed plasma is in thermodynamic equilibrium, the result obtained in the present paper reduces immediately to that previously discussed by Oberman and Shure.

Ching-Sheng Wu

1965-10-04T23:59:59.000Z

222

Field Verification of Energy and Demand Savings of Two Injection Molding Machines Retrofitted with Variable Frequency Drives  

E-Print Network [OSTI]

Detailed field measurements of energy consumption (kWh) and demand (kW) are conducted on two injection molding machines (IMMs) used in a typical plastic manufacturing facility in the San Francisco Bay Area, with/without Variable Frequency Drives...

Liou, S. P.; Aguiar, D.

223

Electromagnetic Signals from Bacterial DNA  

E-Print Network [OSTI]

Chemical reactions can be induced at a distance due to the propagation of electromagnetic signals during intermediate chemical stages. Although is is well known at optical frequencies, e.g. photosynthetic reactions, electromagnetic signals hold true for muck lower frequencies. In E. coli bacteria such electromagnetic signals can be generated by electric transitions between energy levels describing electrons moving around DNA loops. The electromagnetic signals between different bacteria within a community is a "wireless" version of intercellular communication found in bacterial communities connected by "nanowires". The wireless broadcasts can in principle be of both the AM and FM variety due to the magnetic flux periodicity in electron energy spectra in bacterial DNA orbital motions.

A. Widom; J. Swain; Y. N. Srivastava; S. Sivasubramanian

2012-02-09T23:59:59.000Z

224

Some Wave Equations for Electromagnetism and Gravitation  

E-Print Network [OSTI]

The paper studies the inferences of wave equations for electromagnetic fields when there are gravitational fields at the same time. In the description with the algebra of octonions, the inferences of wave equations are identical with that in conventional electromagnetic theory with vector terminology. By means of the octonion exponential function, we can draw out that the electromagnetic waves are transverse waves in a vacuum, and rephrase the law of reflection, Snell's law, Fresnel formula, and total internal reflection etc. The study claims that the theoretical results of wave equations for electromagnetic strength keep unchanged in the case for coexistence of gravitational and electromagnetic fields. Meanwhile the electric and magnetic components of electromagnetic waves can not be determined simultaneously in electromagnetic fields.

Zi-Hua Weng

2010-08-11T23:59:59.000Z

225

Semiconductor converters of electric energy electromagnetic and electromechanical processes in an electric drive under frequency converter parallel operation to induction motor  

Science Journals Connector (OSTI)

The processes occurring in the two PWM-controlled frequency converters operating in parallel to an induction motor in the high-power electric drives start and self-start modes ... current consumed from the suppl...

D. V. Belyaev; A. M. Veinger; G. B. Lazarev

2007-05-01T23:59:59.000Z

226

Course Outline Physics 433: Electromagnetism II  

E-Print Network [OSTI]

Course Outline Physics 433: Electromagnetism II Spring 2014 Prof. Keun Hyuk "Ken" Ahn 483 Tiernan of this course is on the elementary concepts of electromagnetic fields. Upon completion of the course, students are expected to be capable of using the Maxwell equations to calculate simple electromagnetic problems, ranging

227

611: Electromagnetic Theory Problem Sheet 5  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 5 (1) Consider the expression for the electric field due · dS over a spherical surface that encloses the moving charge. (2a) Consider an electromagnetic wave density and the Poynting vector. (2c) Repeat the steps in (2a) and (2b) for an electromagnetic wave

Pope, Christopher

228

611: Electromagnetic Theory Problem Sheet 6  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 6 (1) Consider the expression for the electric field due · dS over a spherical surface that encloses the moving charge. (2a) Consider an electromagnetic wave density and the Poynting vector. (2c) Repeat the steps in (2a) and (2b) for an electromagnetic wave

Pope, Christopher

229

Electromagnetics from Simulation to Optimal Design  

E-Print Network [OSTI]

1 Electromagnetics from Simulation to Optimal Design Christian Hafner Laboratory for Electromagnetic Fields and Microwave Electronics (IFH) ETH Zurich (Switzerland) Lab: http://www.ifh.ee.ethz.ch COG 23, 2013 #12;2 IFH courses · Advanced engineering electromagnetics (Leuchtmann, start spring 2014

Lang, Annika

230

LOW-FREQUENCY IMAGING OF FIELDS AT HIGH GALACTIC LATITUDE WITH THE MURCHISON WIDEFIELD ARRAY 32 ELEMENT PROTOTYPE  

SciTech Connect (OSTI)

The Murchison Widefield Array (MWA) is a new low-frequency, wide-field-of-view radio interferometer under development at the Murchison Radio-astronomy Observatory in Western Australia. We have used a 32 element MWA prototype interferometer (MWA-32T) to observe two 50 Degree-Sign diameter fields in the southern sky, covering a total of {approx}2700 deg{sup 2}, in order to evaluate the performance of the MWA-32T, to develop techniques for epoch of reionization experiments, and to make measurements of astronomical foregrounds. We developed a calibration and imaging pipeline for the MWA-32T, and used it to produce {approx}15' angular resolution maps of the two fields in the 110-200 MHz band. We perform a blind source extraction using these confusion-limited images, and detect 655 sources at high significance with an additional 871 lower significance source candidates. We compare these sources with existing low-frequency radio surveys in order to assess the MWA-32T system performance, wide-field analysis algorithms, and catalog quality. Our source catalog is found to agree well with existing low-frequency surveys in these regions of the sky and with statistical distributions of point sources derived from Northern Hemisphere surveys; it represents one of the deepest surveys to date of this sky field in the 110-200 MHz band.

Williams, Christopher L.; Hewitt, Jacqueline N.; Levine, Alan M. [MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA (United States); De Oliveira-Costa, Angelica; Hernquist, Lars L.; Bernardi, Gianni [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Bowman, Judd D. [School of Earth and Space Exploration, Arizona State University, Tempe, AZ (United States); Briggs, Frank H. [Research School of Astronomy and Astrophysics, The Australian National University, Canberra (Australia); Gaensler, B. M.; Mitchell, Daniel A.; Subrahmanyan, Ravi; Sadler, Elaine M. [ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) (Australia); Morales, Miguel F. [Department of Physics, University of Washington, Seattle, WA (United States); Sethi, Shiv K. [Raman Research Institute, Bangalore (India); Arcus, Wayne; Crosse, Brian W. [International Centre for Radio Astronomy Research, Curtin University, Perth (Australia); Barnes, David G. [Center for Astrophysics and Supercomputing, Swinburne University of Technology, Melbourne (Australia); Bunton, John D. [CSIRO Astronomy and Space Science, Epping (Australia); Cappallo, Roger C.; Corey, Brian E., E-mail: clmw@mit.edu [MIT Haystack Observatory, Westford, MA (United States); and others

2012-08-10T23:59:59.000Z

231

Radio-frequency measurements of UNiX compounds (X= Al, Ga, Ge) in high magnetic fields  

SciTech Connect (OSTI)

We performed radio-frequency (RF) skin-depth measurements of antiferromagnetic UNiX compounds (X=Al, Ga, Ge) in magnetic fields up to 60 T and at temperatures between 1.4 to {approx}60 K. Magnetic fields are applied along different crystallographic directions and RF penetration-depth was measured using a tunnel-diode oscillator (TDO) circuit. The sample is coupled to the inductive element of a TDO resonant tank circuit, and the shift in the resonant frequency {Delta}f of the circuit is measured. The UNiX compounds exhibit field-induced magnetic transitions at low temperatures, and those transitions are accompanied by a drastic change in {Delta}f. The results of our skin-depth measurements were compared with previously published B-T phase diagrams for these three compounds.

Mielke, Charles H [Los Alamos National Laboratory; Mcdonald, David R [Los Alamos National Laboratory; Zapf, Vivien [Los Alamos National Laboratory; Altarawneh, Moaz M [Los Alamos National Laboratory; Lacerda, Alex H [Los Alamos National Laboratory; Adak, Sourav [Los Alamos National Laboratory; Karunakar, Kothapalli [Los Alamos National Laboratory; Nakotte, Heinrich [Los Alamos National Laboratory; Chang, S [NIST; Alsmadi, A M [HASHEMITE UNIV; Alyones, S [HASHEMIT UNIV

2009-01-01T23:59:59.000Z

232

Strong-field high-frequency approximation to the multiphoton ionization of hydrogen  

Science Journals Connector (OSTI)

The strong-field multiphoton ionization of atoms is considered and a theoretical approach dealing nonperturbatively with the radiation field formulated. The general computational...

Trombetta, F; Basile, S; Ferrante, G

1990-01-01T23:59:59.000Z

233

Transferrin Binding to Two Human Colon Carcinoma Cell Lines: Characterization and Effect of 60-Hz Electromagnetic Fields  

Science Journals Connector (OSTI)

...12-O-tetradecanoylphorbol-13-acetate. 6522 MAGNETIC FIELD AND c-fos EXPRESSION...from center (mm) Fig. 1. Distributions of magnetic field intensity along the center line of a permanent magnet; (a) at the surface...

Jerry L. Phillips; Loyce Rutledge; and Wendell D. Winters

1986-01-01T23:59:59.000Z

234

Space-time Curvature of Classical Electromagnetism  

E-Print Network [OSTI]

The space-time curvature carried by electromagnetic fields is discovered and a new unification of geometry and electromagnetism is found. Curvature is invariant under charge reversal symmetry. Electromagnetic field equations are examined with De Rham co homology theory. Radiative electromagnetic fields must be exact and co exact to preclude unobserved massless topological charges. Weyl's conformal tensor, here called ``the gravitational field'', is decomposed into a divergence-free non-local piece with support everywhere and a local piece with the same support as the matter. By tuning a local gravitational field to a Maxwell field the electromagnetic field's local gravitational field is discovered. This gravitational field carries the electromagnetic field's polarization or phase information, unlike Maxwell's stress-energy tensor. The unification assumes Einstein's equations and derives Maxwell's equations from curvature assumptions. Gravity forbids magnetic monopoles! This unification is stronger than the Einstein-Maxwell equations alone, as those equations must produce the electromagnetic field's local gravitational field and not just any conformal tensor. Charged black holes are examples. Curvature of radiative null electromagnetic fields is characterized.

R. W. M. Woodside

2004-10-08T23:59:59.000Z

235

H{sup -} beam extraction from a cesium seeded field effect transistor based radio frequency negative hydrogen ion source  

SciTech Connect (OSTI)

H{sup -} beam was successfully extracted from a cesium seeded ion source operated using a field effect transistor inverter power supply as a radio frequency (RF) wave source. High density hydrogen plasma more than 10{sup 19} m{sup -3} was obtained using an external type antenna with RF frequency of lower than 0.5 MHz. The source was isolated by an isolation transformer and H{sup -} ion beam was extracted from a single aperture. Acceleration current and extraction current increased with the increase of extraction voltage. Addition of a small amount of cesium vapor into the source enhanced the currents.

Ando, A.; Matsuno, T.; Funaoi, T.; Tanaka, N. [School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Tsumori, K.; Takeiri, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan)

2012-02-15T23:59:59.000Z

236

Definition: Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Techniques Electromagnetic Techniques The objective of electromagnetic (EM) techniques is to image the electrical resistivity structure of the subsurface through the measurement of naturally- or artificially-generated electromagnetic fields.[1] View on Wikipedia Wikipedia Definition The electromagnetic force is one of the four fundamental interactions in nature, the other three being the strong interaction, the weak interaction, and gravitation. This force is described by electromagnetic fields, and has innumerable physical instances including the interaction of electrically charged particles and the interaction of uncharged magnetic force fields with electrical conductors. The word electromagnetism is a compound form of two Greek terms, ἢλεκτρον, ēlektron, "amber", and μαγνήτης, magnētēs, "magnet". The science

237

MagLab - Making an Electromagnet Activity  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

theyre basically a wire conducting electric current, which in turn generates a magnetic field. Magnetism and electricity are very closely related phenomena. Electromagnets...

238

Quantum Monte Carlo calculations of electromagnetic moments and transitions in A{<=}9 nuclei including meson-exchange currents derived from chiral effective field theory  

SciTech Connect (OSTI)

Quantum Monte Carlo calculations of electromagnetic moments and transitions are reported for A{<=}9 nuclei. The realistic Argonne v{sub 18} two-nucleon and Illinois-7 three-nucleon potentials are used to generate the nuclear wave functions. Contributions of two-body meson-exchange current (MEC) operators are included for magnetic moments and M1 transitions. The MEC operators have been derived in both a standard nuclear physics approach and a chiral effective field theory formulation with pions and nucleons including up to one-loop corrections. The two-body MEC contributions provide significant corrections and lead to very good agreement with experiment. Their effect is particularly pronounced in the A=9, T=3/2 systems, in which they provide up to ~20% (~40%) of the total predicted value for the {sup 9}Li ({sup 9}C) magnetic moment.

Saori Pastore, S.C. Pieper, Rocco Schiavilla, Robert Wiringa

2013-03-01T23:59:59.000Z

239

High-frequency and -field EPR and FDMRS study of the [Fe(H2O)6]2+ ion in ferrous  

E-Print Network [OSTI]

High-frequency and -field EPR and FDMRS study of the [Fe(H2O)6]2+ ion in ferrous fluorosilicate J online 29 September 2011 Keywords: High-field EPR Spin Hamiltonian Zero-field splitting Iron(II) a b Resonance (EPR) at conventional frequencies (9­95 GHz) and fields (0­3.5 T), the non-Kramers (integer spin

McQuade, D. Tyler

240

An investigation into the vector ellipticity of extremely low frequency magnetic fields from appliances in UK homes  

Science Journals Connector (OSTI)

Elliptically polarized magnetic fields induce higher currents in the body compared with their plane polarized counterparts. This investigation examines the degree of vector ellipticity of extremely low frequency magnetic fields (ELF-MFs) in the home, with regard to the adverse health effects reportedly associated with ELF-MFs, for instance childhood leukaemia. Tri-axial measurements of the magnitude and phase of the 0?3000 Hz magnetic fields, produced by 226 domestic mains-fed appliances of 32 different types, were carried out in 16 homes in Worcestershire in the summer of 2004. Magnetic field strengths were low, with average (RMS) values of 0.03 ? 0.02 ?T across all residences. In contrast, background field ellipticities were high, on average 47 ? 11%. Microwave and electric ovens produced the highest ellipticities: mean respective values of 21 ? 21% and 21 ? 17% were observed 20 cm away from these appliances. There was a negative correlation between field strength and field polarization, which we attribute to the higher relative field contribution close to each individual (single-phase) appliance. The measurements demonstrate that domestic magnetic fields are extremely complex and cannot simply be characterized by traditional measurements such as time-weighted average or peak exposure levels. We conclude that ellipticity should become a relevant metric for future epidemiological studies of health and ELF-MF exposure.

Elizabeth A Ainsbury; Emma Conein; Denis L Henshaw

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Operation of the CAPRICE electron cyclotron resonance ion source applying frequency tuning and double frequency heating  

SciTech Connect (OSTI)

The properties of the electromagnetic waves heating the electrons of the ECR ion sources (ECRIS) plasma affect the features of the extracted ion beams such as the emittance, the shape, and the current, in particular for higher charge states. The electron heating methods such as the frequency tuning effect and the double frequency heating are widely used for enhancing the performances of ECRIS or even for the routine operation during the beam production. In order to better investigate these effects the CAPRICE ECRIS has been operated using these techniques. The ion beam properties for highly charged ions have been measured with beam diagnostic tools. The reason of the observed variations of this performance can be related to the different electromagnetic field patterns, which are changing inside the plasma chamber when the frequency is varying.

Maimone, F. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Universita degli Studi di Catania, D.M.F.C.I, Viale A. Doria 6, 95125 Catania (Italy); Tinschert, K.; Lang, R.; Maeder, J.; Rossbach, J.; Spaedtke, P. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Celona, L. [INFN-LNS, Via S. Sofia 62, 95123 Catania (Italy)

2012-02-15T23:59:59.000Z

242

Elec Eng 2FH3 Electromagnetics I COURSE NUMBER & TITLE: Elec Eng 2FH3 Electromagnetics I  

E-Print Network [OSTI]

Elec Eng 2FH3 ­ Electromagnetics I COURSE NUMBER & TITLE: Elec Eng 2FH3 ­ Electromagnetics I field 6. Inductance 7. Faraday's law CALENDAR DESCRIPTION: Electromagnetics Part I is an introduction into engineering electromagnetics. It covers the mathematical foundations such as selected topics of vector

Haykin, Simon

243

Observation of strong electromagnetic fields around laser-entrance holes of ignition-scale hohlraums in inertial-confinement fusion experiments at the National Ignition Facility  

Science Journals Connector (OSTI)

Energy spectra and spectrally resolved one-dimensional fluence images of self-emitted charged-fusion products (14.7MeV D3He protons) are routinely measured from indirectly driven inertial-confinement fusion (ICF) experiments utilizing ignition-scaled hohlraums at the National Ignition Facility (NIF). A striking and consistent feature of these images is that the fluence of protons leaving the ICF target in the direction of the hohlraum's laser entrance holes (LEHs) is very nonuniform spatially, in contrast to the very uniform fluence of protons leaving through the hohlraum equator. In addition, the measured nonuniformities are unpredictable, and vary greatly from shot to shot. These observations were made separately at the times of shock flash and of compression burn, indicating that the asymmetry persists even at ~0.52.5ns after the laser has turned off. These phenomena have also been observed in experiments on the OMEGA laser facility with energy-scaled hohlraums, suggesting that the underlying physics is similar. Comprehensive data sets provide compelling evidence that the nonuniformities result from proton deflections due to strong spontaneous electromagnetic fields around the hohlraum LEHs. Although it has not yet been possible to uniquely determine whether the fields are magnetic (B) or electric (E), preliminary analysis indicates that the strength is ~1MG if B fields or ~109Vcm?1 if E fields. These measurements provide important physics insight into the ongoing ignition experiments at the NIF. Understanding the generation, evolution, interaction and dissipation of the self-generated fields may help to answer many physics questions, such as why the electron temperatures measured in the LEH region are anomalously large, and may help to validate hydrodynamic models of plasma dynamics prior to plasma stagnation in the center of the hohlraum.

C K Li; A B Zylstra; J A Frenje; F H Sguin; N Sinenian; R D Petrasso; P A Amendt; R Bionta; S Friedrich; G W Collins; E Dewald; T Dppner; S H Glenzer; D G Hicks; O L Landen; J D Kilkenny; A J Mackinnon; N Meezan; J Ralph; J R Rygg; J Kline; G Kyrala

2013-01-01T23:59:59.000Z

244

Sensitivity of calcium binding in cerebral tissue to weak environmental electric fields oscillating at low frequency  

Science Journals Connector (OSTI)

...dulated carrier wave alone (147 MHz, 0.8 mW/cm2). In the...106 at frequencies below 1.0 kHz occur at porous surfaces of...39, 40) has modeled the plasma membrane as a sheet of dipoles...elektrischer Vorginge in der Atmosphire auf den Menschen," Naturwissenschaften...

S M Bawin; W R Adey

1976-01-01T23:59:59.000Z

245

High-frequency vortex dynamics and dissipation of high-temperature superconductors  

Science Journals Connector (OSTI)

The high-frequency vortex dynamics of high-temperature superconductors near the flux-line depinning threshold is investigated based on a thermally activated flux-flow (TAFF) model. Dissipation due to vortex motion driven by a microwave electromagnetic field is studied as a function of the frequency, temperature, dc magnetic field, and microwave power. The generalized TAFF model is also compared to the conventional flux-creep theory and is found qualitatively consistent.

N.-C. Yeh

1991-01-01T23:59:59.000Z

246

Gravitation and electromagnetism  

E-Print Network [OSTI]

Maxwell's equations comprise both electromagnetic and gravitational fields. The transverse part of the vector potential belongs to magnetism, the longitudinal one is concerned with gravitation. The Coulomb gauge indicates that longitudinal components of the fields propagate instantaneously. The delta-function singularity of the field of the divergence of the vector potential, referred to as the dilatation center, represents an elementary agent of gravitation. Viewing a particle as a source or a scattering center of the point dilatation, the Newton's gravitation law can be reproduced.

V. P. Dmitriyev

2002-07-23T23:59:59.000Z

247

Electromagnetic two-dimensional analysis of trapped-ion eigenmodes  

SciTech Connect (OSTI)

A two-dimensional electromagnetic analysis of the trapped-ion instability for the tokamak case with ..beta.. not equal to 0 has been made, based on previous work in the electrostatic limit. The quasineutrality condition and the component of Ampere's law along the equilibrium magnetic field are solved for the perturbed electrostatic potential and the component of the perturbed vector potential along the equilibrium magnetic field. The general integro-differential equations are converted into a matrix eigenvalue-eigenfunction problem by expanding in cubic B-spline finite elements in the minor radius and in Fourier harmonics in the poloidal angle. A model MHD equilibrium with circular, concentric magnetic surfaces and large aspect ratio is used which is consistent with our assemption that B << 1. The effect on the trapped-ion mode of including these electromagnetic extensions to the calculation is considered, and the temperature (and ..beta..) scaling of the mode frequency is shown and discussed.

Kim, D.; Rewoldt, G.

1984-11-01T23:59:59.000Z

248

A new electromagnetic code for ICRF antenna in EAST  

E-Print Network [OSTI]

The demand for an effective tool to help in the design of ion cyclotron radio frequency (ICRF) antenna system for fusion experiment has driven the development of predictive codes. A new electromagnetic code based on the method of moments (MOM) is described in the paper. The code computes the electromagnetic field by the solution of the electric field integral equation. The structure of ICRF antennas are discretized with triangular mesh. By using the new code, the scattering parameter and the surface current are given and compared with the result by commercial code CST. Moreover, the power spectra are studied with different toroidal phases for heating and current drive. Good agreement of simulation results between the new code and CST are obtained. The code has been validated against CST for EAST ICRF antenna.

Yang, Hua; Dong, Sa; Zhang, Xin-Jun; Zhao, Yan-Ping; Shang, Lei

2015-01-01T23:59:59.000Z

249

Strong permanent magnet-assisted electromagnetic undulator  

DOE Patents [OSTI]

This invention discloses an improved undulator comprising a plurality of electromagnet poles located along opposite sides of a particle beam axis with alternate north and south poles on each side of the beam to cause the beam to wiggle or undulate as it travels generally along the beam axis and permanent magnets spaced adjacent the electromagnetic poles on each side of the axis of said particle beam in an orientation sufficient to reduce the saturation of the electromagnet poles whereby the field strength of the electromagnet poles can be increased beyond the normal saturation levels of the electromagnetic poles.

Halbach, Klaus (Berkeley, CA)

1988-01-01T23:59:59.000Z

250

HIGH-FREQUENCY RADIO SPECTRAL ENERGY DISTRIBUTIONS AND POLARIZATION FRACTIONS OF SOURCES IN AN ATACAMA COSMOLOGY TELESCOPE SURVEY FIELD  

SciTech Connect (OSTI)

We present flux densities and polarization percentages of 159 radio galaxies based on nearly simultaneous Very Large Array observations at four frequencies, 4.86, 8.46, 22.46, and 43.34 GHz. This sample is selected from the high-frequency Australia Telescope 20 GHz (AT20G) survey and consists of all sources with flux density S{sub 20GHz} > 40 mJy in an equatorial field of the Atacama Cosmology Telescope (ACT) survey. For a subset of 25 of these sources, we used the Green Bank Telescope (GBT) to obtain 90 GHz data. The goals of this program are: (1) a characterization of the spectra, polarization, and variability of high-frequency-selected radio sources, (2) extrapolating from the few GHz regime to the {approx}150 GHz regime of the ACT survey, allowing for more accurate removal of the radio source signal in our particular field, and (3) providing a data set that will allow more accurate modeling of the high-frequency radio source contamination in current and future Sunyaev-Zeldovich and cosmic microwave background experiments. We find that, as expected, this sample consists of flatter spectrum and more compact or point-like sources than low-frequency-selected samples. In the K band, variability is typically {approx}<20%, although there are exceptions. The higher frequency data are well suited to the detection of extreme gigahertz peak spectrum sources. The inclusion of the 43 GHz data causes the relative fraction of inverted spectrum sources to go down and of peaked spectrum sources to go up when compared with the AT20G survey results. The trend largely continues with the inclusion of the 90 GHz data, although {approx}10% of the sources with GBT data show a spectral upturn from 43 GHz to 90 GHz. The measured polarization fractions are typically <5%, although in some cases they are measured to be up to {approx}20%. For sources with detected polarized flux in all four bands, about 40% of the sample, the polarization fractions typically increase with frequency. This trend is stronger for steeper spectrum sources as well as for the lower flux density sources.

Sajina, Anna [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Partridge, Bruce; Evans, Tyler; Vechik, Nicholas [Department of Physics and Astronomy, Haverford College, Haverford, PA 19041 (United States); Stefl, Shannon [Kent State University, Kent, OH 44242 (United States); Myers, Steve [National Radio Astronomy Observatory, Socorro, NM 87801 (United States); Dicker, Simon; Korngut, Phillip [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States)

2011-05-01T23:59:59.000Z

251

Multi-frequency ESR studies on a Haldane magnet in a field-induced phase at ultra-low temperatures  

Science Journals Connector (OSTI)

We report the results of multi-frequency electron spin resonance (ESR) measurements on single crystals of Ni(C5H14N2)2N3(PF6) which is regarded as the one-dimensional Heisenberg antiferromagnet with spin one, namely the Haldane magnet, at very low temperatures down to about 100 mK. We observed the lowest resonance branch below about 500 mK for the field along the chain direction (H||c), which was observed previously only in an inelastic neutron scattering experiment at 30 mK. We compare the resonance branch with that calculated by a phenomenological field theory, and discuss the field dependence and the temperature sensitivity of this ESR branch.

Masayuki Hagiwara; Takanari Kashiwagi; Yuichi Idutsu; Zentaro Honda; Hiroshi Miyazaki; Isao Harada

2010-01-01T23:59:59.000Z

252

Engineering Sciences 151 Electromagnetic Communication  

E-Print Network [OSTI]

Engineering Sciences 151 Electromagnetic Communication Laboratory Assignment 1 Fall Term 1998, Audio frequency spectrum analyzer Tektronix, Model 2230, 100MHz Dual-channel storage oscilloscope generator Hewlett-Packard, Model 200CD, Wide range audio oscillator General Radio, Model 1398-A, Pulse

Jones, R. Victor

253

Progress In Electromagnetics Research M, Vol. 35, 173182, 2014 Three-Dimensional Analytical Model for an Axial-Field  

E-Print Network [OSTI]

--In this paper, we propose an analytical method for modeling a permanent magnets axial field magnetic coupling. Shaft Rout Magnets Soft-Iron yoke h h Rin e To load From motor Magnetic coupling Figure 1. Structure equipped with axially magnetized permanent magnets (PMs). The PMs are glued on an iron yoke to form a north

Paris-Sud XI, Université de

254

Electromagnetic Waves Propagation in 3D Plasma Configurations  

E-Print Network [OSTI]

Electromagnetic Waves Propagation in 3D Plasma Configurations Pavel Popovich, W. Anthony Cooper such method is based on heating the plasma by electromagnetic waves with various frequencies. Wave behaviour that allows to simulate mode-conversion effects. The wave equation is formulated in terms of electromagnetic

255

Intrinsic Magnetic Fields  

Science Journals Connector (OSTI)

Emission theory of electromagnetic fields.(1) Intrinsic magnetic field. The intrinsic magnetic field of a point charge is defined as that portion of the field which cannot be annihilated by the Lorentz transformation. It is shown that the intrinsic field can be represented by lines of force carried by the same moving elements as carry the electric field, and a potential is given for it. (2) Frequency of emission of moving elements. A relation between the frequency of emission of moving elements and the number of lines of force to a tube is deduced on the assumption that the latter number is the same for the electric and magnetic fields and that each moving element marks the intersection of an electric and magnetic line of force.

Leigh Page

1923-08-01T23:59:59.000Z

256

Electromagnetic Reciprocity.  

SciTech Connect (OSTI)

A reciprocity theorem is an explicit mathematical relationship between two different wavefields that can exist within the same space - time configuration. Reciprocity theorems provi de the theoretical underpinning for mod ern full waveform inversion solutions, and also suggest practical strategies for speed ing up large - scale numerical modeling of geophysical datasets . In the present work, several previously - developed electromagnetic r eciprocity theorems are generalized to accommodate a broader range of medi um, source , and receiver types. Reciprocity relations enabling the interchange of various types of point sources and point receivers within a three - dimensional electromagnetic model are derived. Two numerical modeling algorithms in current use are successfully tested for adherence to reciprocity. Finally, the reciprocity theorem forms the point of departure for a lengthy derivation of electromagnetic Frechet derivatives. These mathe matical objects quantify the sensitivity of geophysical electromagnetic data to variatio ns in medium parameters, and thus constitute indispensable tools for solution of the full waveform inverse problem. ACKNOWLEDGEMENTS Sandia National Labor atories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000. Signif icant portions of the work reported herein were conducted under a Cooperative Research and Development Agreement (CRADA) between Sandia National Laboratories (SNL) and CARBO Ceramics Incorporated. The author acknowledges Mr. Chad Cannan and Mr. Terry Pa lisch of CARBO Ceramics, and Ms. Amy Halloran, manager of SNL's Geophysics and Atmospheric Sciences Department, for their interest in and encouragement of this work. Special thanks are due to Dr . Lewis C. Bartel ( recently retired from Sandia National Labo ratories and now a geophysical consultant ) and Dr. Chester J. Weiss (recently rejoined with Sandia National Laboratories) for many stimulating (and reciprocal!) discussions regar ding the topic at hand.

Aldridge, David F.

2014-11-01T23:59:59.000Z

257

SURVEY OF RESIDENTIAL POWER-FREQUENCY MAGNETIC FIELDS IN MELBOURNE, AUSTRALIA  

Science Journals Connector (OSTI)

......methodology described by Karipidis(9). Instrumentation Magnetic fields were measured using calibrated EMDEX II triaxial meters (Enertech Consultants, CA, USA). The EMDEX meters were calibrated before and after the survey using a Helmholtz coil facility, and......

Ken K Karipidis

2014-04-01T23:59:59.000Z

258

Linear electric field frequency shift (important for next generation electric dipole moment searches) induced in confined gases by a magnetic field gradient  

E-Print Network [OSTI]

The search for particle electric dipole moments (edm) represents a most promising way to search for physics beyond the standard model. A number of groups are planning a new generation of experiments using stored gases of various kinds. In order to achieve the target sensitivities it will be necessary to deal with the systematic error resulting from the interaction of the well-known $\\overrightarrow{v}\\times \\overrightarrow{E}$ field with magnetic field gradients (often referred to as the geometric phase effect (Commins, ED; Am. J. Phys. \\QTR{bf}{59}, 1077 (1991), Pendlebury, JM \\QTR{em}{et al;} Phys. Rev. \\QTR{bf}{A70}, 032102 (2004)). This interaction produces a frequency shift linear in the electric field, mimicking an edm. In this work we introduce an analytic form for the velocity auto-correlation function which determines the velocity-position correlation function which in turn determines the behavior of the frequency shift (Lamoreaux, SK and Golub, R; Phys. Rev \\QTR{bf}{A71}, 032104 (2005)) and show how it depends on the operating conditions of the experiment. We also discuss some additional issues.

Authors A. L. Barabanov; R. Golub; S. K. Lamoreaux

2006-07-17T23:59:59.000Z

259

Acceleration of electrons in the near field of lower hybrid frequency grills  

SciTech Connect (OSTI)

On Tore Supra, during lower hybrid (LH) current drive experiments, localized heat flux deposition is observed on plasma facing components such as the guard limiters of the LH grills or any object which is magnetically connected to the LH launching waveguides : modular low-field side limiters, ion cyclotron heating antennas, inner first wall. Similar observations have been made on the divertor plates and limiters of TdeV. In particular, by alternating the rf powers of the 2 grills of Tore Supra, it was shown that the heat flux on the tiles of the guard limiters is related to the local electric field but not with the convective power. We present here a model of acceleration of electrons in the near field of LH antennas. Results of this model are compared to experimental results.

Goniche, M. [JET Joint Undertaking, Abingdon, Oxfordshire (England); Mailloux, J.; Demers, Y.; Jacquet, P.; Bibet, P.; Froissard, P.; Rey, G.; Surle, F.; Tareb, M. [Centre canadien de fusion magnetique, Varnnes, Quebec, (Canada); Guilhem, D.; Harris, J.H. [Oak Ridge National Lab., TN (United States)

1996-09-01T23:59:59.000Z

260

Poynting-vector based method for determining the bearing and location of electromagnetic sources  

DOE Patents [OSTI]

A method and apparatus is utilized to determine the bearing and/or location of sources, such as, alternating current (A.C.) generators and loads, power lines, transformers and/or radio-frequency (RF) transmitters, emitting electromagnetic-wave energy for which a Poynting-Vector can be defined. When both a source and field sensors (electric and magnetic) are static, a bearing to the electromagnetic source can be obtained. If a single set of electric (E) and magnetic (B) sensors are in motion, multiple measurements permit location of the source. The method can be extended to networks of sensors allowing determination of the location of both stationary and moving sources.

Simons, David J. (Modesto, CA); Carrigan, Charles R. (Tracy, CA); Harben, Philip E. (Livermore, CA); Kirkendall, Barry A. (Golden, CO); Schultz, Craig A. (Danville, CA)

2008-10-21T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Computational Electronics and Electromagnetics  

SciTech Connect (OSTI)

The Computational Electronics and Electromagnetics thrust area is a focal point for computer modeling activities in electronics and electromagnetics in the Electronics Engineering Department of Lawrence Livermore National Laboratory (LLNL). Traditionally, they have focused their efforts in technical areas of importance to existing and developing LLNL programs, and this continues to form the basis for much of their research. A relatively new and increasingly important emphasis for the thrust area is the formation of partnerships with industry and the application of their simulation technology and expertise to the solution of problems faced by industry. The activities of the thrust area fall into three broad categories: (1) the development of theoretical and computational models of electronic and electromagnetic phenomena, (2) the development of useful and robust software tools based on these models, and (3) the application of these tools to programmatic and industrial problems. In FY-92, they worked on projects in all of the areas outlined above. The object of their work on numerical electromagnetic algorithms continues to be the improvement of time-domain algorithms for electromagnetic simulation on unstructured conforming grids. The thrust area is also investigating various technologies for conforming-grid mesh generation to simplify the application of their advanced field solvers to design problems involving complicated geometries. They are developing a major code suite based on the three-dimensional (3-D), conforming-grid, time-domain code DSI3D. They continue to maintain and distribute the 3-D, finite-difference time-domain (FDTD) code TSAR, which is installed at several dozen university, government, and industry sites.

DeFord, J.F.

1993-03-01T23:59:59.000Z

262

Resonant second harmonic generation of a Gaussian electromagnetic beam in a collisional magnetoplasma  

SciTech Connect (OSTI)

Second harmonic generation of a right circularly polarized Gaussian electromagnetic beam in a magnetized plasma is investigated. The beam causes Ohmic heating of electrons and subsequent redistribution of the plasma, leading to self-defocusing. The radial density gradient, in conjunction with the oscillatory electron velocity, produces density oscillation at the wave frequency. The density oscillation beats with the oscillatory velocity to produce second harmonic current density, giving rise to resonant second harmonic radiation when the wave frequency is one-third of electron cyclotron frequency. The second harmonic field has azimuthal dependence as exp(i{theta}). The self-defocusing causes a reduction in the efficiency of harmonic generation.

Kaur, Sukhdeep; Sharma, A. K. [Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi 110016 (India); Salih, Hyder A. [Department of Applied Sciences, University of Baghdad, Baghdad (Iraq)

2009-04-15T23:59:59.000Z

263

Radio-frequency dispersive detection of donor atoms in a field-effect transistor  

SciTech Connect (OSTI)

Radio-frequency dispersive read-out can provide a useful probe to nano-scale structures, such as nano-wire devices, especially, when the implementation of charge sensing is not straightforward. Here, we demonstrate dispersive gate-only read-out of phosphor donors in a silicon nano-scale transistor. The technique enables access to states that are only tunnel-coupled to one contact, which is not easily achievable by other methods. This allows us to locate individual randomly placed donors in the device channel. Furthermore, the setup is naturally compatible with high bandwidth access to the probed donor states and may aid the implementation of a qubit based on coupled donors.

Verduijn, J., E-mail: a.verduijn@unsw.edu.au; Rogge, S. [Centre for Quantum Computation and Communication Technology, University of New South Wales, Sydney NSW 2052 (Australia)] [Centre for Quantum Computation and Communication Technology, University of New South Wales, Sydney NSW 2052 (Australia); Vinet, M. [CEA/LETI-MINATEC, CEA-Grenoble, 17 rue des martyrs, F-38054 Grenoble (France)] [CEA/LETI-MINATEC, CEA-Grenoble, 17 rue des martyrs, F-38054 Grenoble (France)

2014-03-10T23:59:59.000Z

264

Unmanned airborne vehicle (UAV): Flight testing and evaluation of two-channel E-field very low frequency (VLF) instrument  

SciTech Connect (OSTI)

Using VLF frequencies, transmitted by the Navy`s network, for airborne remote sensing of the earth`s electrical, magnetic characteristics was first considered by the United States Geological Survey (USGS) around the mid 1970s. The first VLF system was designed and developed by the USGS for installation and operation on a single engine, fixed wing aircraft used by the Branch of Geophysics for geophysical surveying. The system consisted of five channels. Two E-field channels with sensors consisting of a fixed vertical loaded dipole antenna with pre-amp mounted on top of the fuselage and a gyro stabilized horizontal loaded dipole antenna with pre-amp mounted on a tail boom. The three channel magnetic sensor consisted of three orthogonal coils mounted on the same gyro stabilized platform as the horizontal E-field antenna. The main features of the VLF receiver were: narrow band-width frequency selection using crystal filters, phase shifters for zeroing out system phase variances, phase-lock loops for generating real and quadrature gates, and synchronous detectors for generating real and quadrature outputs. In the mid 1990s the Branch of Geophysics designed and developed a two-channel E-field ground portable VLF system. The system was built using state-of-the-art circuit components and new concepts in circuit architecture. Small size, light weight, low power, durability, and reliability were key considerations in the design of the instrument. The primary purpose of the instrument was for collecting VLF data during ground surveys over small grid areas. Later the system was modified for installation on a Unmanned Airborne Vehicle (UAV). A series of three field trips were made to Easton, Maryland for testing and evaluating the system performance.

NONE

1998-12-01T23:59:59.000Z

265

Fiber optic probe of free electron evanescent fields in the optical frequency range Jin-Kyu So, Kevin F. MacDonald, and Nikolay I. Zheludev  

E-Print Network [OSTI]

, Kevin F. MacDonald, and Nikolay I. Zheludev Citation: Applied Physics Letters 104, 201101 (2014); doi evanescent fields in the optical frequency range Jin-Kyu So,1,a) Kevin F. MacDonald,1 and Nikolay I. Zheludev

Zheludev, Nikolay

266

High-frequency conductivity of type-I superlattices  

Science Journals Connector (OSTI)

By using a method which employs a kinetic description and linear-response theory, we calculated the conductivity of electron-ion many-layer system (type-I superlattices) in the high-frequency and long-wavelength limits. Here electromagnetic radiation is taken to be a homogeneous, oscillating electric field. Our calculation takes into account all contributions in lowest order of the plasma parameter rs. Expressions for frequency-dependent scattering time and effective mass have been numerically obtained. Asymptotic limits for small and large frequencies are analytically derived.

Narkis Tzoar and Chao Zhang

1985-07-15T23:59:59.000Z

267

Generally covariant model of a scalar field with high frequency dispersion and the cosmological horizon problem  

E-Print Network [OSTI]

Short distance structure of spacetime may show up in the form of high freqency dispersion. Although such dispersion is not locally Lorentz invariant, we show in a scalar field model how it can nevertheless be incorporated into a generally covariant metric theory of gravity provided the locally preferred frame is dynamical. We evaluate the resulting energy-momentum tensor and compute its expectation value for a quantum field in a thermal state. The equation of state differs at high temperatures from the usual one, but not by enough to impact the problems of a hot big bang cosmology. We show that a superluminal dispersion relation can solve the horizon problem via superluminal equilibration, however it cannot do so while remaining outside the Planck regime unless the dispersion relation is artificially chosen to have a rather steep dependence on wavevector.

Ted Jacobson; David Mattingly

2000-09-11T23:59:59.000Z

268

Electromagnetic radiation from a plasma slab during the development of Weibel instability  

SciTech Connect (OSTI)

Electromagnetic radiation from an anisotropic plasma slab formed by ionization of matter in the field of a high-power femtosecond pulse is studied. It is shown that the growth of initial field perturbations in the course of Weibel instability is accompanied by the generation of nonmonochromatic radiation with a characteristic frequency on the order of the instability growth rate. It is found that perturbations with characteristic scale lengths less than or on the order of the ratio of the speed of light to the Langmuir frequency are excited and radiated most efficiently, provided that the slab is thicker than this ratio.

Vagin, K. Yu.; Romanov, A. Yu.; Uryupin, S. A. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

2012-01-15T23:59:59.000Z

269

Electromagnetic wave scattering by Schwarzschild black holes  

E-Print Network [OSTI]

We analyze the scattering of a planar monochromatic electromagnetic wave incident upon a Schwarzschild black hole. We obtain accurate numerical results from the partial wave method for the electromagnetic scattering cross section, and show that they are in excellent agreement with analytical approximations. The scattering of electromagnetic waves is compared with the scattering of scalar, spinor and gravitational waves. We present a unified picture of the scattering of all massless fields for the first time.

Lus C. B. Crispino; Sam R. Dolan; Ednilton S. Oliveira

2009-05-20T23:59:59.000Z

270

Mathematical model of the seismic electromagnetic signals (SEMS) in non crystalline substances  

SciTech Connect (OSTI)

The mathematical model of seismic electromagnetic waves in non crystalline substances is developed and the solutions are discussed to show the possibility of improving the electromagnetic waves especially the electric field. The shear stress of the medium in fourth order tensor gives the equation of motion. Analytic methods are selected for the solutions written in Hansen vector form. From the simulated SEMS, the frequency of seismic waves has significant effects to the SEMS propagating characteristics. EM waves transform into SEMS or energized seismic waves. Traveling distance increases once the frequency of the seismic waves increases from 100% to 1000%. SEMS with greater seismic frequency will give seismic alike waves but greater energy is embedded by EM waves and hence further distance the waves travel.

Dennis, L. C. C.; Yahya, N.; Daud, H.; Shafie, A. [Electromagnetic cluster, Universiti Teknologi Petronas, 31750 Tronoh, Perak (Malaysia)

2012-09-26T23:59:59.000Z

271

Electromagnetically induced transparency in mechanical effects of light  

SciTech Connect (OSTI)

We consider the dynamical behavior of a nanomechanical mirror in a high-quality cavity under the action of a coupling laser and a probe laser. We demonstrate the existence of the analog of electromagnetically induced transparency (EIT) in the output field at the probe frequency. Our calculations show explicitly the origin of EIT-like dips as well as the characteristic changes in dispersion from anomalous to normal in the range where EIT dips occur. Remarkably the pump-probe response for the optomechanical system shares all the features of the {Lambda} system as discovered by Harris and collaborators.

Agarwal, G. S.; Huang, Sumei [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2010-04-15T23:59:59.000Z

272

The Covariant Description of Electromagnetically Polarizable Media  

E-Print Network [OSTI]

The form of the phenomenological stress-energy-momentum tensor for the electromagnetic field in a class of inhomogeneous, anisotropic magneto-electric media is calculated from first principles, leading to a coherent understanding of the phenomenological stresses and energy-momentum exchanges induced by electromagnetic interactions with such matter in terms of a fully relativistic covariant variational framework.

T. Dereli; J. Gratus; R. W. Tucker

2006-10-26T23:59:59.000Z

273

Synchrotron Radiation at Radio Frequencies from Cosmic Ray Air Showers  

E-Print Network [OSTI]

We review some of the properties of extensive cosmic ray air showers and describe a simple model of the radio-frequency radiation generated by shower electrons and positrons as they bend in the Earth's magnetic field. We perform simulations by calculating the trajectory and radiation of a few thousand charged shower particles. The results are then transformed to predict the strength and polarization of the electromagnetic radiation emitted by the whole shower.

Denis A. Suprun; Peter W. Gorham; Jonathan L. Rosner

2003-06-06T23:59:59.000Z

274

Synchrotron Radiation at Radio Frequencies from Cosmic Ray Air Showers  

E-Print Network [OSTI]

We review some of the properties of extensive cosmic ray air showers and describe a simple model of the radio-frequency radiation generated by shower electrons and positrons as they bend in the Earth's magnetic field. We perform simulations by calculating the trajectory and radiation of a few thousand charged shower particles. The results are then transformed to predict the strength and polarization of the electromagnetic radiation emitted by the whole shower.

Suprun, D A; Rosner, Jonathan L; Suprun, Denis A.; Gorham, Peter W.; Rosner, Jonathan L.

2003-01-01T23:59:59.000Z

275

Category:Electromagnetic Profiling Techniques | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Category Edit History Facebook icon Twitter icon » Category:Electromagnetic Profiling Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Electromagnetic Profiling Techniques page? For detailed information on Electromagnetic Profiling Techniques, click here. Category:Electromagnetic Profiling Techniques Add.png Add a new Electromagnetic Profiling Techniques Technique Pages in category "Electromagnetic Profiling Techniques" This category contains only the following page. F Frequency-Domain Electromagnetic Survey Retrieved from "http://en.openei.org/w/index.php?title=Category:Electromagnetic_Profiling_Techniques&oldid=689835"

276

Characterization and performance of a field aligned ion cyclotron range of frequency antenna in Alcator C-Mod  

SciTech Connect (OSTI)

Ion cyclotron range of frequency (ICRF) heating is expected to provide auxiliary heating for ITER and future fusion reactors where high Z metallic plasma facing components (PFCs) are being considered. Impurity contamination linked to ICRF antenna operation remains a major challenge particularly for devices with high Z metallic PFCs. Here, we report on an experimental investigation to test whether a field aligned (FA) antenna can reduce impurity contamination and impurity sources. We compare the modification of the scrape of layer (SOL) plasma potential of the FA antenna to a conventional, toroidally aligned (TA) antenna, in order to explore the underlying physics governing impurity contamination linked to ICRF heating. The FA antenna is a 4-strap ICRF antenna where the current straps and antenna enclosure sides are perpendicular to the total magnetic field while the Faraday screen rods are parallel to the total magnetic field. In principle, alignment with respect to the total magnetic field minimizes integrated E|| (electric field along a magnetic field line) via symmetry. A finite element method RF antenna model coupled to a cold plasma model verifies that the integrated E|| should be reduced for all antenna phases. Monopole phasing in particular is expected to have the lowest integrated E||. Consistent with expectations, we observed that the impurity contamination and impurity source at the FA antenna are reduced compared to the TA antenna. In both L and H-mode discharges, the radiated power is 20%30% lower for a FA-antenna heated discharge than a discharge heated with the TA-antennas. However, inconsistent with expectations, we observe RF induced plasma potentials (via gas-puff imaging and emissive probes to be nearly identical for FA and TA antennas when operated in dipole phasing). Moreover, the highest levels of RF-induced plasma potentials are observed using monopole phasing with the FA antenna. Thus, while impurity contamination and sources are indeed reduced with the FA antenna configuration, the mechanism determining the SOL plasma potential in the presence of ICRF and its impact on impurity contamination and sources remains to be understood.

Wukitch, S. J.; Garrett, M. L.; Ochoukov, R.; Terry, J. L.; Hubbard, A.; Labombard, B.; Lau, C.; Lin, Y.; Lipschultz, B.; Miller, D.; Reinke, M. L.; Whyte, D. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States)] [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Collaboration: Alcator C-Mod Team

2013-05-15T23:59:59.000Z

277

Electromagnetism on Anisotropic Fractals  

E-Print Network [OSTI]

We derive basic equations of electromagnetic fields in fractal media which are specified by three indepedent fractal dimensions {\\alpha}_{i} in the respective directions x_{i} (i=1,2,3) of the Cartesian space in which the fractal is embedded. To grasp the generally anisotropic structure of a fractal, we employ the product measure, so that the global forms of governing equations may be cast in forms involving conventional (integer-order) integrals, while the local forms are expressed through partial differential equations with derivatives of integer order but containing coefficients involving the {\\alpha}_{i}'s. First, a formulation based on product measures is shown to satisfy the four basic identities of vector calculus. This allows a generalization of the Green-Gauss and Stokes theorems as well as the charge conservation equation on anisotropic fractals. Then, pursuing the conceptual approach, we derive the Faraday and Amp\\`ere laws for such fractal media, which, along with two auxiliary null-divergence conditions, effectively give the modified Maxwell equations. Proceeding on a separate track, we employ a variational principle for electromagnetic fields, appropriately adapted to fractal media, to independently derive the same forms of these two laws. It is next found that the parabolic (for a conducting medium) and the hyperbolic (for a dielectric medium) equations involve modified gradient operators, while the Poynting vector has the same form as in the non-fractal case. Finally, Maxwell's electromagnetic stress tensor is reformulated for fractal systems. In all the cases, the derived equations for fractal media depend explicitly on fractal dimensions and reduce to conventional forms for continuous media with Euclidean geometries upon setting the dimensions to integers.

Martin Ostoja-Starzewski

2011-06-08T23:59:59.000Z

278

Force-free plasma currents driven by electromagnetic oscillations with E parallel to B  

Science Journals Connector (OSTI)

A special superposition of oppositely propagating circularly polarized monochromatic plane waves defines a stationary electromagnetic oscillation in a cavity, with E parallel to B. Inside a plasma, this type of oscillation induces an ac current J that is parallel to the magnetic field B, and is hence force free. In the low-frequency limit, a transient dc plasma current is driven by the special oscillation field. It is shown that these oscillations cannot interact with an externally imposed field B0, so that they exist only if J?B?B0.

N. A. Salingaros

1992-06-15T23:59:59.000Z

279

Heating mechanisms in radio-frequency-driven ultracold plasmas  

Science Journals Connector (OSTI)

Several mechanisms by which an external electromagnetic field influences the temperature of a plasma are studied analytically and specialized to the system of an ultracold plasma (UCP) driven by a uniform radio-frequency (rf) field. Heating through collisional absorption is reviewed and applied to UCPs. Furthermore, it is shown that the rf field modifies the three-body recombination process by ionizing electrons from intermediate high-lying Rydberg states and upshifting the continuum threshold, resulting in a suppression of three-body recombination. Heating through collisionless absorption associated with the finite plasma size is calculated in detail, revealing a temperature threshold below which collisionless absorption is ineffective.

P. W. Smorenburg; L. P. J. Kamp; O. J. Luiten

2012-06-20T23:59:59.000Z

280

Electromagnetic wave scattering by small perfectly conducting particles and applications  

E-Print Network [OSTI]

A formula for the electromagnetic (EM) field in the medium, in which many small perfectly conducting particles of an arbitrary shape are distributed, is derived.

Alexander G. Ramm

2014-02-13T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Curve crossing and negative refraction in simulations of near-field coupled metallic nanoparticle arrays  

E-Print Network [OSTI]

Curve crossing and negative refraction in simulations of near-field coupled metallic nanoparticle-polariton LSPP dispersion on regular arrays of metal nanoparticles in the weak-field and weak-damping limits nanoparticle ar- rays to guide electromagnetic energy of optical frequencies along geometries smaller than

Baer, Roi

282

Frequency domain and finite difference modeling of ventilated concrete slabs and comparison with field measurements: Part 2. Application  

Science Journals Connector (OSTI)

Abstract This paper is the second of two papers that present techniques and guidelines for frequency response (FR) and lumped-parameter finite difference (LPFD) approaches for the thermal modeling of building-integrated thermal energy storage (BITES) systems. To assist the thermal analysis and control of active BITES systems, development of FR and LPFD models are presented in this two-part paper. Modeling methodology and techniques are presented in paper Part 1 using ventilated concrete slabs (VCS) for demonstration. In this part, the methodology is applied to two types of VCS. The modeling results from different FR and explicit LPFD models with different time steps and discretization schemes are presented. The results are compared to each other, and with field-measured data from a solar demonstration house with a VCS. Simulation results show that time step of half an hour for FR models results in less than 3% error in thermal performance. For LPFD models, discretization with Biot number smaller than 0.5 can reduce error to about 5%.

Yuxiang Chen; Andreas K. Athienitis; Khaled E. Galal

2013-01-01T23:59:59.000Z

283

Slice-based supine to standing postured deformation for Chinese anatomical models and the dosimetricresults by wide band frequency electromagnetic field exposure: morphing  

Science Journals Connector (OSTI)

......evaluating the difference in the whole body and organic-level EMF power deposition for the supine and standing postures. So, it is...2008) 53:4093-4106. 12 Aggarwal J. K. , Cai Q. Human motion analysis: a review. (1997) Proceedings of the IEEE: San......

Tongning Wu; Liwen Tan; Qing Shao; Ying Li; Lei Yang; Chen Zhao; Yi Xie; Shaoxiang Zhang

2013-04-01T23:59:59.000Z

284

Unification of Electromagnetism and Gravitation in the Framework of General Geometry  

E-Print Network [OSTI]

A new geometry, called General geometry, is constructed. It is proven that its the most simplest special case is geometry underlying Electromagnetism. Another special case is Riemannian geometry. Action for electromagnetic field and Maxwell equations are derived from curvature function of geometry underlying Electromagnetism. It is shown that equation of motion for a particle interacting with electromagnetic field coincides exactly with equation for geodesics of geometry underlying Electromagnetism. It is also shown that Electromagnetism can not be geometrized in the framework of Riemannian geometry. Using General Geometry we propose a unified model of electromagnetism and gravitation which reproduces Electromagnetism and Gravitation and predicts that electromagnetic field is a source for gravitational field. This theory is formulated in four dimensional spacetime and does not contain additional fields.

Shervgi Shahverdiyev

2005-07-05T23:59:59.000Z

285

Electromagnetic modeling of the energy distribution of a metallic cylindrical parabolic reflector covered with a magnetized plasma layer  

SciTech Connect (OSTI)

The energy distribution along the focal axis of a long metallic cylindrical parabolic reflector with a plasma layer on its surface in the presence of an external magnetic field is investigated. The effects of some physical parameters, such as the plasma frequency, the wave frequency and the thickness of plasma layer on the energy distribution and the reflected and transmitted electromagnetic fields, are simulated. These investigations for both S- and P-polarizations have been done separately. It is found that the maximum value of the reflected intensity increases by increasing the incident wave frequency and by decreasing the plasma layer thickness and the plasma frequency for both polarizations. Furthermore, the results show that the increase of the magnetic field strength can cause an increase in the reflected intensity for S-polarization and a slight decrease for P-polarization.

Niknam, A. R., E-mail: a-niknam@sbu.ac.ir; Khajehmirzaei, M. R. [Laser and Plasma Research Institute, Shahid Beheshti University, GC, Tehran (Iran, Islamic Republic of); Davoudi-Rahaghi, B.; Rahmani, Z.; Jazi, B.; Abdoli-Arani, A. [Department of Laser and Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)

2014-07-15T23:59:59.000Z

286

Analysis Of Factors Affecting Natural Source Slf Electromagnetic  

Open Energy Info (EERE)

Factors Affecting Natural Source Slf Electromagnetic Factors Affecting Natural Source Slf Electromagnetic Exploration At Geothermal Wells Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Analysis Of Factors Affecting Natural Source Slf Electromagnetic Exploration At Geothermal Wells Details Activities (0) Areas (0) Regions (0) Abstract: The Super Low Frequency (SLF) electromagnetic exploration was performed by using a nature source SLF electromagnetic detector at two geothermal wells in Peking University. The data of the SLF electromagnetic exploration at well JR-119 and JR-168 were obtained with the observation of continued five days and four times per day at well JR-119 and of one day at well JR-168. Based on these data, the influencing factors of the SI-F electromagnetic exploration were analyzed, which included the relationship

287

REPORT NAME (CLICK FOR A SAMPLE) DESCRIPTION FREQUENCY KEY FIELDS Budget Allocation & Transfer Report Provides a line detail view of budget allocation and transfer  

E-Print Network [OSTI]

REPORT NAME (CLICK FOR A SAMPLE) DESCRIPTION FREQUENCY KEY FIELDS Budget Allocation & Transfer Report Provides a line detail view of budget allocation and transfer transactions by department as of a specific mid-month or month-end period (i.e. accounting period). Report can be sorted by Account, Fund

de Lijser, Peter

288

Low-frequency anomalies in spectral ratios of single station microtremor measurements: Observations across an oil and gas field in Austria  

E-Print Network [OSTI]

Low-frequency anomalies in spectral ratios of single station microtremor measurements: Observations across an oil and gas field in Austria Marc Lambert and Stefan M. Schmalholz, Geological Institute, ETH are calculated from the different components of ground motion measured at single stations. An example

Podladchikov, Yuri

289

Frequency-Selective Near-Field Radiative Heat Transfer between Photonic Crystal Slabs: A Computational Approach for Arbitrary Geometries and Materials  

E-Print Network [OSTI]

of energy from a hot to a cold body is well known to be enhanced (even exceeding the black- body limit) whenFrequency-Selective Near-Field Radiative Heat Transfer between Photonic Crystal Slabs of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA 3 Department

Soljaèiæ, Marin

290

Electromagnetic properties of neutrinos  

E-Print Network [OSTI]

A short review on electromagnetic properties of neutrinos is presented. In spite of many efforts in the theoretical and experimental studies of neutrino electromagnetic properties, they still remain one of the main puzzles related to neutrinos.

Carlo Giunti; Alexander Studenikin

2010-06-08T23:59:59.000Z

291

ON THE INFLUENCE OF THE GEOMETRY ON SKIN EFFECT IN ELECTROMAGNETISM  

E-Print Network [OSTI]

ON THE INFLUENCE OF THE GEOMETRY ON SKIN EFFECT IN ELECTROMAGNETISM GABRIEL CALOZ, MONIQUE DAUGE, ERWAN FAOU, VICTOR P´ERON ABSTRACT. We consider the equations of electromagnetism set on a domain made in electromagnetism. This effect describes the rapid decay of electromagnetic fields with depth inside a metallic

Dauge, Monique

292

Electromagnetic Measurements at RHIC  

E-Print Network [OSTI]

Electromagnetic Measurements at RHIC Hideki Hamagaki Center for Nuclear Study University of Tokyo #12;2/10/2005 "Electromagnetic measurements at RHIC"@ICPAQGP 05 Hideki Hamagaki 2 Prologue · EM probe and where they are produced; #12;2/10/2005 "Electromagnetic measurements at RHIC"@ICPAQGP 05 Hideki Hamagaki

Hamagaki, Hideki

293

Electromagnetic Measurements at RHIC  

E-Print Network [OSTI]

Electromagnetic Measurements at RHIC Hideki Hamagaki Center for Nuclear Study Graduate School of Science the University of Tokyo #12;2006/06/29 "Electromagnetic measurements at RHIC"@ATHIC 2006 Hideki;2006/06/29 "Electromagnetic measurements at RHIC"@ATHIC 2006 Hideki Hamagaki 3 Prologue ­ scope of EM measurements · EM

Hamagaki, Hideki

294

Electromagnetic torque analysis of a DFIG for wind turbines  

Science Journals Connector (OSTI)

Electromagnetic torque of doubly fed induction generator (DFIG) is a consequence of the rotor and stator supply. The stator voltage has a fixed amount and frequency. The rotor voltage of the DFIG as a part of a wind turbine has a variable amount and ... Keywords: DFIG, electromagnetic torque, renewable energy, wind turbine

Jurica Smajo; Dinko Vukadinovic

2008-05-01T23:59:59.000Z

295

Electromagnetic space-time crystals. II. Fractal computational approach  

E-Print Network [OSTI]

A fractal approach to numerical analysis of electromagnetic space-time crystals, created by three standing plane harmonic waves with mutually orthogonal phase planes and the same frequency, is presented. Finite models of electromagnetic crystals are introduced, which make possible to obtain various approximate solutions of the Dirac equation. A criterion for evaluating accuracy of these approximate solutions is suggested.

G. N. Borzdov

2014-10-20T23:59:59.000Z

296

Electromagnetic waves, gravitational coupling and duality analysis  

E-Print Network [OSTI]

In this letter we introduce a particular solution for parallel electric and magnetic fields, in a gravitational background, which satisfy free-wave equations and the phenomenology suggested by astrophysical plasma physics. These free-wave equations are computed such that the electric field does not induce the magnetic field and vice-versa. In a gravitational field, we analyze the Maxwell equations and the corresponding electromagnetic waves. A continuity equation is presented. A commutative and noncommutative analysis of the electromagnetic duality is described.

E. M. C. Abreu; C. Pinheiro; S. A. Diniz; F. C. Khanna

2005-10-27T23:59:59.000Z

297

E-Print Network 3.0 - account electromagnetic transient Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

crucial points of winding modelling in electromagnetic devices... , a cylindrical magnetizer coil is investigated for low frequency sinusoidal excitation and in a transient......

298

Definition: Time-Domain Electromagnetics | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Time-Domain Electromagnetics Jump to: navigation, search Dictionary.png Time-Domain Electromagnetics Time-domain electromagnetic (TDEM) surveys are active-source soundings which provide information about the electrical structure of the shallow subsurface.[1] View on Wikipedia Wikipedia Definition Transient electromagnetics, (also time-domain electromagnetics / TDEM), is a geophysical exploration technique in which electric and magnetic fields are induced by transient pulses of electric current and the subsequent decay response measured. TEM / TDEM methods are generally able to determine subsurface electrical properties, but are also sensitive to subsurface magnetic properties in applications like UXO detection and

299

A strong permanent magnet-assisted electromagnetic undulator  

DOE Patents [OSTI]

This invention discloses an improved undulator comprising a plurality of electromagnet poles located along opposite sides of a particle beam axis with alternate north and south poles on each side of the beam to cause the beam to wiggle or undulate as it travels generally along the beam axis and permanent magnets spaced adjacent the electromagnetic poles on each side of the axis of said particle beam in an orientation sufficient to reduce the saturation of the electromagnet poles whereby the field strength of the electromagnet poles can be increased beyond the normal saturation levels of the electromagnetic poles. 4 figs.

Halbach, K.

1987-01-30T23:59:59.000Z

300

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  

SciTech Connect (OSTI)

Energy generated by the worlds 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 Energys (DOEs) 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).

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

2013-05-20T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Velocity damper for electromagnetically levitated materials  

DOE Patents [OSTI]

A system for damping oscillatory and spinning motions induced in an electromagnetically levitated material is disclosed. Two opposed field magnets are located orthogonally to the existing levitation coils for providing a DC quadrupole field (cusp field) around the material. The material used for generating the DC quadrupole field must be nonconducting to avoid eddy-current heating and of low magnetic permeability to avoid distorting the induction fields providing the levitation. 1 fig.

Fox, R.J.

1994-06-07T23:59:59.000Z

302

The Mammalian Brain in the Electromagnetic Fields Designed by Man with Special Reference to Blood-Brain Barrier Function, Neuronal Damage and Possible Physical Mechanisms  

Science Journals Connector (OSTI)

......their emitted energy. The SAR Fig...exposure. At a frequency of 900 MHz, these...25 W/m2 at a frequency of 900 MHz. In...RF exposure, response is only seen at...important for energy transfer and storage in biological......

Leif G. Salford; Henrietta Nittby; Arne Brun; Gustav Grafstrm; Lars Malmgren; Marianne Sommarin; Jacob Eberhardt; Bengt Widegren; Bertil R. R. Persson

2008-02-01T23:59:59.000Z

303

Extremely high frequency RF effects on electronics.  

SciTech Connect (OSTI)

The objective of this work was to understand the fundamental physics of extremely high frequency RF effects on electronics. To accomplish this objective, we produced models, conducted simulations, and performed measurements to identify the mechanisms of effects as frequency increases into the millimeter-wave regime. Our purpose was to answer the questions, 'What are the tradeoffs between coupling, transmission losses, and device responses as frequency increases?', and, 'How high in frequency do effects on electronic systems continue to occur?' Using full wave electromagnetics codes and a transmission-line/circuit code, we investigated how extremely high-frequency RF propagates on wires and printed circuit board traces. We investigated both field-to-wire coupling and direct illumination of printed circuit boards to determine the significant mechanisms for inducing currents at device terminals. We measured coupling to wires and attenuation along wires for comparison to the simulations, looking at plane-wave coupling as it launches modes onto single and multiconductor structures. We simulated the response of discrete and integrated circuit semiconductor devices to those high-frequency currents and voltages, using SGFramework, the open-source General-purpose Semiconductor Simulator (gss), and Sandia's Charon semiconductor device physics codes. This report documents our findings.

Loubriel, Guillermo Manuel; Vigliano, David; Coleman, Phillip Dale; Williams, Jeffery Thomas; Wouters, Gregg A.; Bacon, Larry Donald; Mar, Alan

2012-01-01T23:59:59.000Z

304

Spinors and pre-metric electromagnetism  

E-Print Network [OSTI]

The basic concepts of the formulation of Maxwellian electromagnetism in the absence of a Minkowski scalar product on spacetime are summarized, with particular emphasis on the way that the electromagnetic constitutive law on the space of bivectors over spacetime supplants the role of the Minkowski scalar product on spacetime itself. The complex geometry of the space of bivectors is summarized, with the intent of showing how an isomorphic copy of the Lorentz group appears in that context. The use of complex 3-spinors to represent electromagnetic fields is then discussed, as well as the expansion of scope that the more general complex projective geometry of the space of bivectors suggests.

David Delphenich

2005-12-22T23:59:59.000Z

305

On the Axioms of Topological Electromagnetism  

E-Print Network [OSTI]

The axioms of topological electromagnetism are refined by the introduction of the de Rham homology of k-vector fields on orientable manifolds and the use of Poincare duality in place of Hodge duality. The central problem of defining the electromagnetic constitutive law is elaborated upon in the linear and nonlinear cases. The manner by which the spacetime metric might follow from the constitutive law is examined in the linear case. The possibility that the intersection form of the spacetime manifold might play a role in defining a topological basis for the constitutive law is explored. The manner by which wave motion might follow from the electromagnetic structure is also discussed.

D. H. Delphenich

2003-12-14T23:59:59.000Z

306

A current driven electromagnetic mode in sheared and toroidal configurations  

E-Print Network [OSTI]

The induced electric field in a tokamak drives a parallel electron current flow. In an inhomogeneous, finite beta plasma, when this electron flow is comparable to the ion thermal speed, the Alfven mode wave solutions of the electromagnetic gyrokinetic equation can become nearly purely growing kink modes. Using the new "low-flow" version of the gyrokinetic code GS2 developed for momentum transport studies [Barnes et al 2013 Phys. Rev. Lett. 111, 055005], we are able to model the effect of the induced parallel electric field on the electron distribution to study the destabilizing influence of current on stability. We identify high mode number kink modes in GS2 simulations and make comparisons to analytical theory in sheared magnetic geometry. We demonstrate reassuring agreement with analytical results both in terms of parametric dependences of mode frequencies and growth rates, and regarding the radial mode structure.

Pusztai, Istvn; Parra, Felix I; Barnes, Michael

2013-01-01T23:59:59.000Z

307

Thermal front tracking with cross borehole electromagnetic imaging: Task 32 of Annex 4 of the implementing agreement  

SciTech Connect (OSTI)

Field experiments at the Texaco Kern River Field were conducted to identify optimum transmission frequencies and assess the electromagnetic interference problems present in the system. We concluded that the transmitter must be operated below 3 MHz for attenuation measurements to be in the conduction regime. Operation in the conduction regime is necessary if we are to correlate images to independent measurements such as the dual induction logs. We also concluded that electromagnetic interference problems become more severe as the frequency is lowered. We are currently designing a downhole active transmitter that will operate at 2 MHz. This frequency is low enough to be in the conduction regime and to increase our transmission distance capability, but high enough so that we can still drive a 1 or 2 meter antenna. By driving the antenna with a downhole oscillator we dramatically reduce the chance of electromagnetic interference pathways. Future plans are to test the transmitter at the Texaco field site and demonstrate correlation to induction logs. This will be followed by a brine tracing experiment at the same site. We will then move our equipment to a new pilot test site for a substantial series of cooperative experiments with Texaco. 5 refs., 11 figs.

Harben, P.E.; Pihlman, M.

1988-04-01T23:59:59.000Z

308

Gauge Symmetry and Gravito-Electromagnetism  

E-Print Network [OSTI]

A tensor description of perturbative Einsteinian gravity about an arbitrary background spacetime is developed. By analogy with the covariant laws of electromagnetism in spacetime, gravito-electromagnetic potentials and fields are defined to emulate electromagnetic gauge transformations under substitutions belonging to the gauge symmetry group of perturbative gravitation. These definitions have the advantage that on a flat background, with the aid of a covariantly constant timelike vector field, a subset of the linearised gravitational field equations can be written in a form that is fully analogous to Maxwell's equations (without awkward factors of 4 and extraneous tensor fields). It is shown how the remaining equations in the perturbed gravitational system restrict the time dependence of solutions to these equations and thereby prohibit the existence of propagating vector fields. The induced gravito-electromagnetic Lorentz force on a test particle is evaluated in terms of these fields together with the torque on a small gyroscope. It is concluded that the analogy of perturbative gravity to Maxwell's description of electromagnetism can be valuable for (quasi-)stationary gravitational phenomena but that the analogy has its limitations.

Simon J. Clark; Robin W. Tucker

2000-03-31T23:59:59.000Z

309

Electromagnetic and spin polarisabilities in lattice QCD  

E-Print Network [OSTI]

We discuss the extraction of the electromagnetic and spin polarisabilities of nucleons from lattice QCD. We show that the external field method can be used to measure all the electromagnetic and spin polarisabilities including those of charged particles. We then turn to the extrapolations required to connect such calculations to experiment in the context of chiral perturbation theory, finding a strong dependence on the lattice volume and quark masses.

W. Detmold; B. C. Tiburzi; A. Walker-Loud

2006-10-02T23:59:59.000Z

310

Perturbative Roughness Corrections to Electromagnetic Casimir Energies  

E-Print Network [OSTI]

Perturbative corrections to the Casimir free energy due to macroscopic roughness of dielectric interfaces are obtained in the framework of an effective low-energy field theory. It describes the interaction of electromagnetic fields with materials whose plasma frequency $\\omega_p$ determines the low-energy scale. The na\\"ive perturbative expansion of the single-interface scattering matrix in the variance of the profile is sensitive to short wavelength components of the roughness correlation function. We introduce generalized counter terms that subtract and correct these high-momentum contributions to the loop expansion. To leading order the counter terms are determined by the phenomenological plasmon model. The latter is found to be consistent with the low-energy description. The proximity force approximation is recovered in the limit of long correlation length and gives the upper limit for the roughness correction to the Casimir force. The renormalized low-energy theory is insensitive to the high-momentum behavior of the roughness correlation function. Predictions of the improved theory are compared with those of the unrenormalized model and with experiment. The Casimir interaction of interfaces with low levels of roughness is found to be well reproduced by that of flat parallel plates with the measured reflection coefficients at a distance that is slightly less than the mean separation of the rough surfaces.

Hua Yao Wu; Martin Schaden

2014-02-11T23:59:59.000Z

311

Quantum modulation against electromagnetic interference  

E-Print Network [OSTI]

Periodic signals in electrical and electronic equipment can cause interference in nearby devices. Randomized modulation of those signals spreads their energy through the frequency spectrum and can help to mitigate electromagnetic interference problems. The inherently random nature of quantum phenomena makes them a good control signal. I present a quantum modulation method based on the random statistics of quantum light. The paper describes pulse width modulation schemes where a Poissonian light source acts as a random control that spreads the energy of the potential interfering signals. I give an example application for switching-mode power supplies and comment the further possibilities of the method.

Juan Carlos Garcia-Escartin

2014-11-26T23:59:59.000Z

312

A tunable metamaterial dependent on electric field at terahertz with barium strontium titanate thin film  

SciTech Connect (OSTI)

A tunable metamaterial with resonance frequency at terahertz (THz) was developed. Electromagnetic response of the metamaterial was characterized with THz time domain spectrometer at various direct current electric fields. The resonance frequency increased monotonously with increasing electric field. The finite difference time domain method was used to simulate the transmission spectra of the metamaterial at THz frequencies. By comparing the simulated resonance frequency with the experimental curve, dielectric property of the Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} (BST60) thin film at THz, over 033?kV/cm, was evaluated.

Bian, Yanlong; Zhai, Jiwei, E-mail: apzhai@tongji.edu.cn [Function Materials Research Laboratory, Tongji University, Shanghai 200092 (China); Wu, Chao; Li, Hongqiang [Department of Physics Science and Engineering, Tongji University, Shanghai 200092 (China)

2014-01-27T23:59:59.000Z

313

Simulation of the influence high-frequency (2 MHz) capacitive gas discharge and magnetic field on the plasma sheath near a surface in hypersonic gas flow  

SciTech Connect (OSTI)

The plasma sheath near the surface of a hypersonic aircraft formed under associative ionization behind the shock front shields the transmission and reception of radio signals. Using two-dimensional kinetic particle-in-cell simulations, we consider the change in plasma-sheath parameters near a flat surface in a hypersonic flow under the action of electrical and magnetic fields. The combined action of a high-frequency 2-MHz capacitive discharge, a constant voltage, and a magnetic field on the plasma sheath allows the local electron density to be reduced manyfold.

Schweigert, I. V., E-mail: ischweig@itam.nsc.ru [Russian Academy of Sciences, Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch (Russian Federation)

2012-08-15T23:59:59.000Z

314

Relativistic approach to electromagnetic imaging  

E-Print Network [OSTI]

A novel imaging principle based on the interaction of electromagnetic waves with a beam of relativistic electrons is proposed. Wave-particle interaction is assumed to take place in a small spatial domain, so that each electron is only briefly accelerated by the incident field. In the one-dimensional case the spatial distribution of the source density can be directly observed in the temporal spectrum of the scattered field. Whereas, in the two-dimensional case the relation between the source and the spectrum is shown to be approximately the Radon transform.

Budko, N

2004-01-01T23:59:59.000Z

315

Relativistic approach to electromagnetic imaging  

E-Print Network [OSTI]

A novel imaging principle based on the interaction of electromagnetic waves with a beam of relativistic electrons is proposed. Wave-particle interaction is assumed to take place in a small spatial domain, so that each electron is only briefly accelerated by the incident field. In the one-dimensional case the spatial distribution of the source density can be directly observed in the temporal spectrum of the scattered field. Whereas, in the two-dimensional case the relation between the source and the spectrum is shown to be approximately the Radon transform.

Neil Budko

2004-03-11T23:59:59.000Z

316

Unbalanced electromagnetic forces  

E-Print Network [OSTI]

) . I :, jazdz g (Member) (Member) August 1974 -" ~ 5:. -. 62 ABSTRACT Unbalanced Electromagnetic Forces (August 1974) Craig Martin Hansen, B. S. , Texas A&M University Directed by: Dr. Attilio J. Giaroia Electromagnetic forces from moving... be deduced from the history of the development of an under- standing of electromagnetic forces. This is a relatively short history (starting in the late 1800's) filled with misunderstandings and pre]udices. This history can be divided into two eras: non...

Hansen, Craig Martin

2012-06-07T23:59:59.000Z

317

Electromagnetically driven peristaltic pump  

DOE Patents [OSTI]

An electromagnetic peristaltic pump apparatus may comprise a main body section having an inlet end and an outlet end and a flexible membrane which divides the main body section into a first cavity and a second cavity. The first cavity is in fluid communication with the inlet and outlet ends of the main body section. The second cavity is not in fluid communication with the first cavity and contains an electrically conductive fluid. The second cavity includes a plurality of electrodes which are positioned within the second cavity generally adjacent the flexible membrane. A magnetic field generator produces a magnetic field having a plurality of flux lines at least some of which are contained within the second cavity of the main body section and which are oriented generally parallel to a flow direction in which a material flows between the inlet and outlet ends of the main body section. A control system selectively places a voltage potential across selected ones of the plurality of electrodes to deflect the flexible membrane in a wave-like manner to move material contained in the first cavity between the inlet and outlet ends of the main body section.

Marshall, Douglas W. (Blackfoot, ID)

2000-01-01T23:59:59.000Z

318

Meson electromagnetic form factors  

E-Print Network [OSTI]

The electromagnetic structure of the pseudoscalar meson nonet is completely described by the sophisticated Unitary&Analytic model, respecting all known theoretical properties of the corresponding form factors.

Stanislav Dubnicka; Anna Z. Dubnickova

2012-10-23T23:59:59.000Z

319

The Mammalian Brain in the Electromagnetic Fields Designed by Man with Special Reference to Blood-Brain Barrier Function, Neuronal Damage and Possible Physical Mechanisms  

Science Journals Connector (OSTI)

......irradiation, atmospheric electric fields...exposure to GSM 915 MHz, at non-thermal...fields upon spinach plasma vesicles can steer...irradiation, atmospheric electric fields...solar winds with plasma flows which appear...passage over spinach plasma vesicle membranes...as well 915 MHz continuous wave......

Leif G. Salford; Henrietta Nittby; Arne Brun; Gustav Grafstrm; Lars Malmgren; Marianne Sommarin; Jacob Eberhardt; Bengt Widegren; Bertil R. R. Persson

2008-02-01T23:59:59.000Z

320

High-frequency absorption of the dynamic mixed state in the surface superconductivity region  

SciTech Connect (OSTI)

We analyze the absorption of a high-frequency electromagnetic field in the type II superconductor Pb{sub 0.8}In{sub 0.2} in magnetic fields H{sub c2} < H < H{sub c3}. The absorption component proportional to the rate of variation of the external magnetic field is detected. We assume that this absorption component is associated with the dynamic mixed state of the superconducting shell containing 2D magnetic flux vortices (Kulik vortices). The motion of these vortices under the action of the critical current ensures the required difference between the external and internal magnetic inductions of the superconducting shell upon a change in the external magnetic field. This model correctly describes the observed behavior of absorption of rf electromagnetic radiation.

Berezin, V. A., E-mail: berezin@iptm.ru; Tulin, V. A., E-mail: tulin@iptm.ru [Russian Academy of Sciences, Institute of Microelectronics Technology and High-Purity Materials (Russian Federation)

2013-03-15T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

String loops oscillating in the field of Kerr black holes as a possible explanation of twin high-frequency quasiperiodic oscillations observed in microquasars  

E-Print Network [OSTI]

Small oscillations of current-carrying string loops around stable equilibrium positions corresponding to minima of the effective potential in the equatorial plane of the Kerr black holes are studied using the perturbation method. In the lowest approximation, two uncoupled harmonic oscillators are obtained that govern the radial and vertical oscillations; the higher-order terms determine non-linear phenomena and transition to chaotic motion through quasi-periodic stages of the oscillatory motion. The radial profiles of frequencies of the radial and vertical harmonic oscillations that are relevant also in the quasi-periodic stages of the oscillatory motion are given, and their properties in dependence on the spin of the black holes and the angular momentum and tension of the string loops are determined. It is shown that the radial profiles differ substantially from those corresponding to the radial and vertical frequencies of the geodetical epicyclic motion; however, they have the same mass-scaling and their magnitude is of the same order. Therefore, we are able to demonstrate that assuming relevance of resonant phenomena of the radial and vertical string-loop oscillations at their frequency ratio 3:2, the oscillatory frequencies of string loops can be well related to the frequencies of the twin high-frequency quasi-periodic oscillations (HF QPOs) observed in the microquasars GRS 1915+105, XTE 1550-564, GRO 1655-40. We can conclude that oscillating current-carrying string loops have to be considered as one of the possible explanations of the HF QPOs occurring in the field of compact objects.

Zden?k Stuchlk; Martin Kolo

2014-03-11T23:59:59.000Z

322

Self-consistent particle modeling of radio frequency discharge in Ar/O{sub 2} mixtures: Effects of crossed electric and magnetic fields and partial pressure  

SciTech Connect (OSTI)

A particle-in-cell/Monte Carlo model is developed to study and analyze the electrical characteristics of the nonequilibrium plasma created by radio frequency (RF) discharge in Ar/O{sub 2} mixtures in the presence of crossed electric and magnetic fields. The method of collision treatment is based on an optimized estimation of the free time flight. The needed basic data--more specifically, the ion-neutral cross sections--are determined first. The simulation conditions are 50 mTorr for the total gas pressure and 200 V for the peak of the RF voltage at a frequency of 13.56 MHz. The magnetic field is varied from 0 to 50 G. The effect of the partial pressure ratio of O{sub 2} in the mixture and the effect of the magnitude of the magnetic field are discussed. In particular, the results show an increase of the plasma density that is ten times higher in the presence of a magnetic field.

Benyoucef, Djilali [University of Toulouse, UMR CNRS 5213, Laplace, Toulouse (France); Laboratoire Genie Electrique et Energie Renouvelables, Chlef University (Algeria); Yousfi, Mohammed [University of Toulouse, UMR CNRS 5213, Laplace, Toulouse (France); Belmadani, Bachir [Laboratoire Genie Electrique et Energie Renouvelables, Chlef University (Algeria)

2011-04-15T23:59:59.000Z

323

Tunability enhanced electromagnetic wiggler  

DOE Patents [OSTI]

The invention discloses a wiggler used in synchrotron radiation sources and free electron lasers, where each pole is surrounded by at least two electromagnetic coils. The electromagnetic coils are energized with different amounts of current to provide a wide tunable range of the on-axis magnetic flux density, while preventing magnetic saturation of the poles. 14 figs.

Schlueter, R.D.; Deis, G.A.

1992-03-24T23:59:59.000Z

324

Field Evaluations of Low-Frequency SAFT-UT on Cast Stainless Steel and Dissimilar Metal Weld Components  

SciTech Connect (OSTI)

This report documents work performed at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington, and at the Electric Power Research Institute's (EPRI) Nondestructive Examination (NDE) Center in Charlotte, North Carolina, on evalutating a low frequency ultrasonic inspection technique used for examination of cast stainless steel (CSS) and dissimilar metal (DMW) reactor piping components. The technique uses a zone-focused, multi-incident angle, low frequency (250-450 kHz) inspection protocol coupled with the synthetic aperture focusing technique (SAFT). The primary focus of this work is to provide information to the United States Nuclear Regulatory Commission on the utility, effectiveness and reliability of ultrasonic testing (UT) inspection techniques as related to the inservice ultrasonic inspection of coarse grained primary piping components in pressurized water reactors (PWRs).

Diaz, Aaron A.; Harris, R. V.; Doctor, Steven R.

2008-11-01T23:59:59.000Z

325

Stimulated Raman back scattering of extraordinary electromagnetic waves from periodically magnetized nanoparticle lattice  

SciTech Connect (OSTI)

Stimulated Raman back scattering of extraordinary electromagnetic waves from the nanoparticle lattice is investigated in the presence of the static magnetic field. In the context of macroscopic theory, dispersion relation and growth rate of extraordinary mode for different values of static magnetic field and lattice parameters are derived and analyzed. It is found that when the static magnetic field is off, dispersion relation has two branches. These branches are related to the plasmonic and body wave branches of the plane polarized wave. Low frequency branch of the pump wave is not involved in the instability while the other branch is not stable, and the growth rate of Raman back scattered wave has one peak. If the electrons have cyclotron frequency by static magnetic field, dispersion has three branches. These branches are related to the plasmonic and body wave branches of left and right hand circularly polarized waves. In this situation, it is found that low frequency lower branch of the pump wave is stable while other branches are not stable, and the growth rate of Raman back scattered wave has three peaks. Numerical study of growth rate in various cyclotron frequencies shows that the growth rate increases and the instability band width decreases with increasing static magnetic field.

Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of)] [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of)

2013-06-15T23:59:59.000Z

326

Mitigation of Electromagnetic Pulse (EMP) Effects from Short-Pulse Lasers and Fusion Neutrons  

SciTech Connect (OSTI)

Our research focused on obtaining a fundamental understanding of the source and properties of EMP at the Titan PW(petawatt)-class laser facility. The project was motivated by data loss and damage to components due to EMP, which can limit diagnostic techniques that can be used reliably at short-pulse PW-class laser facilities. Our measurements of the electromagnetic fields, using a variety of probes, provide information on the strength, time duration, and frequency dependence of the EMP. We measure electric field strengths in the 100's of kV/m range, durations up to 100 ns, and very broad frequency response extending out to 5 GHz and possibly beyond. This information is being used to design shielding to mitigate the effects of EMP on components at various laser facilities. We showed the need for well-shielded cables and oscilloscopes to obtain high quality data. Significant work was invested in data analysis techniques to process this data. This work is now being transferred to data analysis procedures for the EMP diagnostics being fielded on the National Ignition Facility (NIF). In addition to electromagnetic field measurements, we measured the spatial and energy distribution of electrons escaping from targets. This information is used as input into the 3D electromagnetic code, EMSolve, which calculates time dependent electromagnetic fields. The simulation results compare reasonably well with data for both the strength and broad frequency bandwidth of the EMP. This modeling work required significant improvements in EMSolve to model the fields in the Titan chamber generated by electrons escaping the target. During dedicated Titan shots, we studied the effects of varying laser energy, target size, and pulse duration on EMP properties. We also studied the effect of surrounding the target with a thick conducting sphere and cube as a potential mitigation approach. System generated EMP (SGEMP) in coaxial cables does not appear to be a significant at Titan. Our results are directly relevant to planned short-pulse ARC (advanced radiographic capability) operation on NIF.

Eder, D C; Throop, A; Brown, Jr., C G; Kimbrough, J; Stowell, M L; White, D A; Song, P; Back, N; MacPhee, A; Chen, H; DeHope, W; Ping, Y; Maddox, B; Lister, J; Pratt, G; Ma, T; Tsui, Y; Perkins, M; O'Brien, D; Patel, P

2009-03-06T23:59:59.000Z

327

Line geometry and electromagnetism III: groups of transformations  

E-Print Network [OSTI]

The role of linear and projective groups of transformations in line geometry and electromagnetism is examined in accordance with Klein's Erlanger Programm for geometries. The group of collineations of real projective space is chosen as the most general group, and reductions to some of its various subgroups are then detailed according to their relevance to electromagnetic fields, and especially wave-like ones.

D. H. Delphenich

2014-04-16T23:59:59.000Z

328

Merging electromagnetism with space-time metric  

E-Print Network [OSTI]

In the present work, it is shown that the electromagnetism may be directly associated to the four-dimensional space-time geometry. The starting point is an analysis of the geodesic equation of general relativity where it is verified that it contains implicitly the effects of the Coulomb and the Lorentz forces. Consequently, some components of the metric tensor are identified with the components of the four-vector electromagnetic potential. Then, it is constructed a low-field equation for the electromagnetism in the same structure of the Einstein field equations for the gravitation, relating the curvature of space-time to sources of charge and current density. In this framework, all the Maxwell equations are implicit. A proof of consistency with the framework of quantum mechanics is shown.

C. A. Duarte

2014-03-10T23:59:59.000Z

329

I. What is electromagnetic radiation and the electromagnetic spectrum?  

E-Print Network [OSTI]

i­1 I. What is electromagnetic radiation and the electromagnetic spectrum? What do light, X effects on matter. This "stuff" is called electromagnetic radiation, because it travels (radiates) and has electrical and magnetic effects. Electromagnetic radiation is the means for many of our interactions

Sitko, Michael L.

330

Frequency domain and finite difference modeling of ventilated concrete slabs and comparison with field measurements: Part 1, modeling methodology  

Science Journals Connector (OSTI)

Abstract This paper is the first of two papers that focus on the thermal modeling of building-integrated thermal energy storage (BITES) systems using frequency response (FR) and lumped-parameter finite difference (LPFD) techniques. Structural/non-structural building fabric components, such as ventilated concrete slabs (VCS) can actively store and release thermal energy effectively by passing air through their embedded air channels. These building components can be described as ventilated BITES systems. To assist the thermal analysis and control of BITES systems, modeling techniques and guidelines for FR and LPFD models of VCS are presented in this two-part paper. In this first part, modeling techniques for FR and LPFD approaches based on network theory are presented. A method for calculating the heat transfer between flowing air and ventilated components is developed for these two approaches. Discretization criteria for explicit LPFD models are discussed. For the FR approach, discrete Fourier series in complex frequency form are used to represent the boundary excitations. In the treatment of heat injection from the flowing air as internal source in the VCS, network techniques such as Thvenin theorem, heat flow division, and Y-diakoptic transform are employed. The techniques presented in this paper are applicable to other BITES with hydronic or electric charging/discharging systems. With the FR techniques, model-based control strategies based on transfer functions can be readily developed.

Yuxiang Chen; Andreas K. Athienitis; Khaled E. Galal

2013-01-01T23:59:59.000Z

331

Zero-Field Splitting in Pseudotetrahedral Co(II) Complexes: a Magnetic, High-Frequency and -Field EPR, and Computational Study  

Science Journals Connector (OSTI)

(4) In this case the correlation is represented by a straight line (in fact by two, nearly collinear, straight lines) for a geometry of compressed/elongated tetragonal bipyramid keeping D4h symmetry. ... magnet behavior in the absence of an applied magnetic field. ... ESR technique in magnetic fields ?17 T. A field-induced development of the soliton-like incommensurate superstructure is clearly indicated as a pronounced increase of the magnon spin resonance linewidth ?B, with a ?Bmax at Bc ? 13.8 T. The anomaly is explained in terms of the magnon-soliton scattering and suggests that the soliton-like phase exists close to the boundary of the dimerized-incommensurate phase transition. ...

Monika Ideicov; Jn Titi; J. Krzystek; Roman Bo?a

2013-08-07T23:59:59.000Z

332

Property:FieldProcedures | Open Energy Information  

Open Energy Info (EERE)

FieldProcedures FieldProcedures Jump to: navigation, search Property Name FieldProcedures Property Type Text Description Description of actions, equipment and footprint of the exploration activity Subproperties This property has the following 39 subproperties: A Active Seismic Techniques Airborne Gravity Survey Audio-Magnetotellurics C Controlled Source Audio MT Cross-Dipole Acoustic Log D DC Resistivity Survey (Dipole-Dipole Array) DC Resistivity Survey (Mise-Á-La-Masse) DC Resistivity Survey (Pole-Dipole Array) DC Resistivity Survey (Schlumberger Array) DC Resistivity Survey (Wenner Array) Development Drilling Direct-Current Resistivity Survey Drilling Techniques E Earth Tidal Analysis Electrical Profiling Configurations Electromagnetic Techniques Exploration Drilling F FMI Log Frequency-Domain Electromagnetic Survey

333

Radial electric field generated by resonant trapped electron pinch with radio frequency injection in a tokamak plasma  

E-Print Network [OSTI]

electrons in the direction parallel to the toroidal field. It was found that, for typical tokamak parameters required in ITER or future reactors. Therefore, it is of great interest to investigate methods of flow and transport was provided in sequential time scales. In addition, an inter-machine comparison of intrinsic

334

field  

National Nuclear Security Administration (NNSA)

9%2A en Ten-Year Site Plans (TYSP) http:nnsa.energy.govaboutusouroperationsinfopsinfopstysp

field field-type-text field-field-page-name">

335

Frequency distribution of mineral elements in samples of alfalfa and sugar beet leaves obtained from a common field in Imperial Valley, California  

SciTech Connect (OSTI)

Baseline measurements were made of mineral composition of alfalfa (Medicago sativa L.) and sugar beets (Beta vulgaris L.) from one field each in the Imperial Valley of California. The fields are in a geothermal area being developed for energy production, and the purpose of the investigation was to ascertain variablility within a relatively large number of samples from a common area, so that subsequent samplings could be made to satisfactorily detect whether there were changes resulting from the geothermal activity. Means, standard deviations, frequency distribution, correlations, cluster trees, and other statistics were examined for over 20 elements at each site.Most elements were normally distributed, but there was three- to fourfold range in the concentration for each.

Wallace, A.; Romney, E.M.; Kinnear, J.

1982-07-01T23:59:59.000Z

336

Asia Pacific Symposium of Applied Electromagnetics and Mechanics (APSAEM2010) Kuala Lumpur, Malaysia, 28-30th  

E-Print Network [OSTI]

, Malaysia, 28-30th July 2010 Reducing Electromagnetic Interference in Non-Isolated DC to DC Step JAMALUDIN*2 Investigation of the Electromagnetic interference (EMI) is important for design of a good power: electromagnetic interference, power converter, EMI, ohmic heating, high frequency. 1. Introduction In order

Hammerton, James

337

Purely electromagnetic spacetimes  

E-Print Network [OSTI]

Electrovacuum solutions devoid of usual mass sources are classified in the case of one, two and three commuting Killing vectors. Three branches of solutions exist. Electromagnetically induced mass terms appear in some of them.

B. V. Ivanov

2007-12-15T23:59:59.000Z

338

The effect of applied electric field on pulsed radio frequency and pulsed direct current plasma jet array  

SciTech Connect (OSTI)

Here we compare the plasma plume propagation characteristics of a 3-channel pulsed RF plasma jet array and those of the same device operated by a pulsed dc source. For the pulsed-RF jet array, numerous long life time ions and metastables accumulated in the plasma channel make the plasma plume respond quickly to applied electric field. Its structure similar as 'plasma bullet' is an anode glow indeed. For the pulsed dc plasma jet array, the strong electric field in the vicinity of the tube is the reason for the growing plasma bullet in the launching period. The repulsive forces between the growing plasma bullets result in the divergence of the pulsed dc plasma jet array. Finally, the comparison of 309 nm and 777 nm emissions between these two jet arrays suggests the high chemical activity of pulsed RF plasma jet array.

Hu, J. T.; Liu, X. Y.; Liu, J. H.; Xiong, Z. L.; Liu, D. W.; Lu, X. P. [National State Key Lab of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, WuHan, Hubei 430074 (China); Iza, F.; Kong, M. G. [Department of Electronic and Electrical Engineering, Loughborough University, Leicestershire LE11 3TU (United Kingdom)

2012-06-15T23:59:59.000Z

339

Quantum Electromagnetic Fluctuations in Inhomogeneous Dielectric Media  

E-Print Network [OSTI]

A new mathematical and computational technique for calculating quantum vacuum expectation values of energy and momentum densities associated with electromagnetic fields in bounded domains containing inhomogeneous media is discussed. This technique is illustrated by calculating the mode contributions to the difference in the vacuum force expectation between opposite ends of an inhomogeneous dielectric non-dispersive medium confined to a perfectly conducting rigid box.

Shin-itiro Goto; Robin W. Tucker; Timothy J. Walton

2011-07-07T23:59:59.000Z

340

Electromagnetic rotational actuation.  

SciTech Connect (OSTI)

There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.

Hogan, Alexander Lee

2010-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Introduction Framework Multiscale Expansion Axisymmetric Problems FEM Simulations Postprocessing A Transmission Problem in Electromagnetism with a  

E-Print Network [OSTI]

A Transmission Problem in Electromagnetism with a Singular Interface GABRIEL CALOZ 2 MONIQUE DAUGE 2 ERWAN FAOU 2´eron A Transmission Problem in Electromagnetism with a Singular Interface 1 / 33 inria-00528523,version1-22Oct2010 of electromagnetic fields with depth inside the conductor. The Skin Depth : () = 2/µ0 V. P´eron A Transmission

Paris-Sud XI, Université de

342

THIN LAYER MODELS FOR ELECTROMAGNETISM MARC DURUFLE, VICTOR PERON, AND CLAIR POIGNARD  

E-Print Network [OSTI]

THIN LAYER MODELS FOR ELECTROMAGNETISM MARC DURUFL´E, VICTOR P´ERON, AND CLAIR POIGNARD ABSTRACT of electromagnetic waves in domains with thin layer. These models appear as first order approximations of the electromagnetic field. They are obtained thanks to a multiscale expansion of the exact solution with respect

Paris-Sud XI, Université de

343

Vacuum energy densities of a field in a cavity with a mobile boundary  

E-Print Network [OSTI]

We consider the zero-point field fluctuations, and the related field energy densities, inside a one-dimensional and a three-dimensional cavity with a mobile wall. The mechanical degrees of freedom of the mobile wall are described quantum mechanically and they are fully included in the overall system dynamics. In this optomechanical system, the field and the wall can interact with each other through the radiation pressure on the wall, given by the photons inside the cavity or even by vacuum fluctuations. We consider two cases: the one-dimensional electromagnetic field and the three-dimensional scalar field, and use the Green's functions formalism, which allows extension of the results obtained for the scalar field to the electromagnetic field. We show that the quantum fluctuations of the position of the cavity's mobile wall significantly affect the field energy density inside the cavity, in particular at the very proximity of the mobile wall. The dependence of this effect from the ultraviolet cutoff frequency, related to the plasma frequency of the cavity walls, is discussed. We also compare our new results for the one-dimensional electromagnetic field and the three-dimensional massless scalar field to results recently obtained for the one-dimensional massless scalar field. We show that the presence of a mobile wall also changes the Casimir-Polder force on a polarizable body placed inside the cavity, giving the possibility to detect experimentally the new effects we have considered.

Federico Armata; Roberto Passante

2015-01-15T23:59:59.000Z

344

Vacuum Energy Densities of a Field in a Cavity with a Mobile Boundary  

E-Print Network [OSTI]

We consider the zero-point field fluctuations, and the related field energy densities, inside a one-dimensional and a three-dimensional cavity with a mobile wall. The mechanical degrees of freedom of the mobile wall are described quantum-mechanically and they are fully included in the overall system dynamics. In this optomechanical system, the field and the wall can interact with each other through the radiation pressure on the wall, given by the photons inside the cavity or even by vacuum fluctuations. We consider two cases: the 1D electromagnetic field and the 3D scalar field, and use the Green's functions formalism, that allows extension of the results obtained for the scalar field to the electromagnetic field. We show that the quantum fluctuations of the position of the cavity's mobile wall significantly affect the field energy density inside the cavity, in particular at the very proximity of the mobile wall. The dependence of this effect from the ultraviolet cut-off frequency, related to the plasma frequency of the cavity walls, is discussed. We also compare our new results for the 1D electromagnetic field and the 3D massless scalar field to results recently obtained for the 1D massless scalar field. We show that the presence of a mobile wall also changes the Casimir-Polder force on a polarizable body placed inside the cavity, giving possibility to detect experimentally the new effects we have considered.

Federico Armata; Roberto Passante

2014-11-19T23:59:59.000Z

345

Gradient instabilities of electromagnetic waves in Hall thruster plasma  

SciTech Connect (OSTI)

This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.

Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)

2013-04-15T23:59:59.000Z

346

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  

SciTech Connect (OSTI)

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 statistically significant. Additional species are currently planned for laboratory testing in the next fiscal year (e.g. an elasmobranch, American lobster) to provide a broader assessment of species important to stakeholders. The collective responses of all species will be assessed in terms of life stage, exposure scenarios, and biological relevance, to address current uncertainties related to effects of EMF on aquatic organisms.

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

2012-05-01T23:59:59.000Z

347

Electromagnetic angular momentum and quantum mechanics  

Science Journals Connector (OSTI)

A quick way of arriving at the Dirac quantization condition between electric and magnetic charges is to require that the electromagnetic field angular momentum of a Thomson dipole (a magnetic monopole and an electric charge) equal some integer multiple of the fundamental unit of quantum mechanical angular momentum ?/2. Applying this same type of argument to the electromagnetic field angular momentum carried by a magnetic dipoleelectric charge system leads to an infinite number of different quantization conditions and an apparent incompatibility between quantum mechanics and the dipolecharge system. However a more careful analysis shows that the particle plus field angular momentum of this system does satisfy the standard angular momentum commutation relationships and is therefore a good quantum mechanical angular momentum. This emphasizes that caution must be taken when applying such semiclassical quantization arguments. Finally a possible connection between this dipolecharge field angular momentum and the nucleon spin crisis is given.

D. Singleton

1998-01-01T23:59:59.000Z

348

Scanning evanescent electro-magnetic microscope  

DOE Patents [OSTI]

A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.

Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Alameda, CA)

2001-01-01T23:59:59.000Z

349

Duality in Off-Shell Electromagnetism  

E-Print Network [OSTI]

In this paper, we examine the Dirac monopole in the framework of Off-Shell Electromagnetism, the five dimensional U(1) gauge theory associated with Stueckelberg-Schrodinger relativistic quantum theory. After reviewing the Dirac model in four dimensions, we show that the structure of the five dimensional theory prevents a natural generalization of the Dirac monopole, since the theory is not symmetric under duality transformations. It is shown that the duality symmetry can be restored by generalizing the electromagnetic field strength to an element of a Clifford algebra. Nevertheless, the generalized framework does not permit us to recover the phenomenological (or conventional) absence of magnetic monopoles.

Martin Land

2006-03-21T23:59:59.000Z

350

Excitation of electrostatic waves in the electron cyclotron frequency range during magnetic reconnection in laboratory overdense plasmas  

SciTech Connect (OSTI)

We report the observation of electromagnetic radiation at high harmonics of the electron cyclotron frequency that was considered to be converted from electrostatic waves called electron Bernstein waves (EBWs) during magnetic reconnection in laboratory overdense plasmas. The excitation of EBWs was attributed to the thermalization of electrons accelerated by the reconnection electric field around the X-point. The radiative process discussed here is an acceptable explanation for observed radio waves pulsation associated with major flares.

Kuwahata, A., E-mail: kuwahata@ts.t.u-tokyo.ac.jp [Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656 (Japan); Igami, H. [National Institute for Fusion Science, Toki 509-5292 (Japan); Kawamori, E. [Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Kogi, Y. [Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Inomoto, M.; Ono, Y. [Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561 (Japan)

2014-10-15T23:59:59.000Z

351

Subsurface characterization using time-domain electromagnetics at the Texas A&M University Brazos River Hydrologic Field Site, Burleson County, Texas  

E-Print Network [OSTI]

data of June 1996 . 47 5. 7 TDEM response of a 2. 0flm resistivity half-space plotted against the Brazos field data of June 1996. . . . . 5. 8 Sensitivity of TDEM response due to small perturbations in TX and RX parameters is shown for a half...-space of p =1. 0flm. . . . . . . . 51 5. 9 Survey error at small TX-RX separation 5. 10 Survey error at a large TX-RX separation FIGURE Page 7. 1 Linc 3 TDFM response of data with and without, thc pipeline 7. 2 Line 6 TDEM response of data with anrl...

Sananikone, Khamla

2012-06-07T23:59:59.000Z

352

Electromagnetic Radiations as a Fluid Flow  

E-Print Network [OSTI]

We combine Maxwell's equations with Eulers's equation, related to a velocity field of an immaterial fluid, where the density of mass is replaced by a charge density. We come out with a differential system able to describe a relevant quantity of electromagnetic phenomena, ranging from classical dipole waves to solitary wave-packets with compact support. The clue is the construction of an energy tensor summing up both the electromagnetic stress and a suitable mass tensor. With this right-hand side, explicit solutions of the full Einstein's equation are computed for a wide class of wave phenomena. Since our electromagnetic waves may behave and interact exactly as a material fluid, they can create vortex structures. We then explicitly analyze some vortex ring configurations and examine the possibility to build a model for the electron.

Daniele Funaro

2009-11-25T23:59:59.000Z

353

EMG #121471 Electromagnetics, 25:679693, 2005  

E-Print Network [OSTI]

. Keywords electromagnetic compatibility, electromagnetic interference, aperture, cou- pling, finite compatibility (EMC) and electromagnetic interference (EMI) requirements, it is crucial to quantify

Ramahi, Omar

354

A new low-frequency backward mode in inhomogeneous plasmas  

SciTech Connect (OSTI)

When an electromagnetic transverse wave propagates through an inhomogeneous plasma so that its electric field has a component in the direction of the background density gradient, there appears a disbalance of charge in every plasma layer, caused by the density gradient. Due to this, some additional longitudinal electric field component appears in the direction of the wave vector. This longitudinal field may couple with the usual electrostatic longitudinal perturbations like the ion acoustic, electron Langmuir, and ion plasma waves. As a result, these standard electrostatic waves are modified and in addition to this a completely new low-frequency mode appears. Some basic features of the coupling and modification of the ion acoustic wave, and properties of the new mode are discussed here, in ordinary electron-ion and in pair plasmas.

Vranjes, J., E-mail: jvranjes@yahoo.com [Institute of Physics, Pregrevica 118, 11080 Zemun, Belgrade (Serbia)

2014-07-15T23:59:59.000Z

355

3. ELECTROMAGNETIC COMPATIBILITY Abstract --The electromagnetic interference between the  

E-Print Network [OSTI]

walls and tubes) and with strong EMI (Electromagnetic Interference). So it is ideal to use the power

Paris-Sud XI, Université de

356

Fluidic electrodynamics: Approach to electromagnetic propulsion  

SciTech Connect (OSTI)

We report on a new methodological approach to electrodynamics based on a fluidic viewpoint. We develop a systematic approach establishing analogies between physical magnitudes and isomorphism (structure-preserving mappings) between systems of equations. This methodological approach allows us to give a general expression for the hydromotive force, thus re-obtaining the Navier-Stokes equation departing from the appropriate electromotive force. From this ground we offer a fluidic approach to different kinds of issues with interest in propulsion, e.g., the force exerted by a charged particle on a body carrying current; the magnetic force between two parallel currents; the Magnus's force. It is shown how the intermingle between the fluid vector fields and electromagnetic fields leads to new insights on their dynamics. The new concepts introduced in this work suggest possible applications to electromagnetic (EM) propulsion devices and the mastery of the principles of producing electric fields of required configuration in plasma medium.

Martins, Alexandre A.; Pinheiro, Mario J. [Institute for Plasmas and Nuclear Fusion and Instituto Superior Tecnico Lisboa, Portugal 351.1.21.841.92.43 (Portugal); Department of Physics and Institute for Plasmas and Nuclear Fusion and Instituto Superior Tecnico Lisboa, Portugal 351.1.21.841.93.22 (Portugal)

2009-03-16T23:59:59.000Z

357

618 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 49, NO. 3, JUNE 2002 A Comparative Study of Carrier-Frequency  

E-Print Network [OSTI]

-frequency modulation (CFM) techniques for the conducted electromagnetic interference (EMI) suppression in pulsewidth. The most direct way of solving electromagnetic interference (EMI) problems is to reduce the emission from

So, Hing-Cheung

358

A generalized Debye source approach to electromagnetic scattering in layered media  

SciTech Connect (OSTI)

The standard solution to time-harmonic electromagnetic scattering problems in homogeneous layered media relies on the use of the electric field dyadic Green's function. However, for small values of the governing angular frequency ?, evaluation of the electric field using this Green's function exhibits numerical instability. In this short note, we provide an alternative approach which is immune from this low-frequency breakdown as ? ? 0. Our approach is based on the generalized Debye source representation of Maxwell fields. Using this formulation, the electric and magnetic fields gracefully decouple in the static limit, a behavior similar to that of the classical Lorenz-Debye-Mie representation of Maxwell fields in spherical geometries. We derive extensions of both the generalized Deybe source and Lorenz-Debye-Mie representations to planar geometries, as well as provide equations for the solution of scattering from a perfectly conducting half-space and in layered media using a Sommerfeld-like approach. These formulas are stable as ? tends to zero, and offer alternatives to the electric field dyadic Green's function.

ONeil, Michael, E-mail: oneil@cims.nyu.edu [Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, New York 10012 (United States)] [Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, New York 10012 (United States)

2014-01-15T23:59:59.000Z

359

Compton Sources of Electromagnetic Radiation  

SciTech Connect (OSTI)

When a relativistic electron beam interacts with a high-field laser beam, intense and highly collimated electromagnetic radiation will be generated through Compton scattering. Through relativistic upshifting and the relativistic Doppler effect, highly energetic polarized photons are radiated along the electron beam motion when the electrons interact with the laser light. For example, X-ray radiation can be obtained when optical lasers are scattered from electrons of tens-of-MeV beam energy. Because of the desirable properties of the radiation produced, many groups around the world have been designing, building, and utilizing Compton sources for a wide variety of purposes. In this review article, we discuss the generation and properties of the scattered radiation, the types of Compton source devices that have been constructed to date, and the prospects of radiation sources of this general type. Due to the possibilities of producing hard electromagnetic radiation in a device that is small compared to the alternative storage ring sources, it is foreseen that large numbers of such sources may be constructed in the future.

Geoffrey Krafft,Gerd Priebe

2011-01-01T23:59:59.000Z

360

Graphene Frequency Multipliers  

E-Print Network [OSTI]

In this letter, the ambipolar transport properties of graphene flakes have been used to fabricate full-wave signal rectifiers and frequency-doubling devices. By correctly biasing an ambipolar graphene field-effect transistor ...

Wang, Han

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Electromagnetic Mass Models in General Theory of Relativity  

E-Print Network [OSTI]

"Electromagnetic mass" where gravitational mass and other physical quantities originate from the electromagnetic field alone has a century long distinguished history. In the introductory chapter we have divided this history into three broad categories -- classical, quantum mechanical and general relativistic. Each of the categories has been described at a length to get the detailed picture of the physical background. Recent developments on Repulsive Electromagnetic Mass Models are of special interest in this introductory part of the thesis. In this context we have also stated motivation of our work. In the subsequent chapters we have presented our results and their physical significances. It is concluded that the electromagnetic mass models which are the sources of purely electromagnetic origin ``have not only heuristic flavor associated with the conjecture of Lorentz but even a physics having unconventional yet novel features characterizing their own contributions independent of the rest of the physics".

Sumana Bhadra

2007-10-30T23:59:59.000Z

362

Televisions, Video Privacy, and Powerline Electromagnetic Interference  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iv Safe Use Guidelines, Electromagnetic Interference, and FCC Warning . . . . . . . . . . . . .v

Matsuoka, Yoky

363

Electromagnetic Radiation REFERENCE: Remote Sensing of  

E-Print Network [OSTI]

1 CHAPTER 2: Electromagnetic Radiation Principles REFERENCE: Remote Sensing of the Environment John;2 Electromagnetic Energy Interactions Energy recorded by remote sensing systems undergoes fundamental interactions, creating convectional currents in the atmosphere. c) Electromagnetic energy in the form of electromagnetic

Gilbes, Fernando

364

Electromagnetically Induced Flows Michiel de Reus  

E-Print Network [OSTI]

Electromagnetically Induced Flows in Water Michiel de Reus 8 maart 2013 () Electromagnetically Conclusion and future research () Electromagnetically Induced Flows 2 / 56 #12;1 Introduction 2 Maxwell Navier Stokes equations 5 Simulations 6 Conclusion and future research () Electromagnetically Induced

Vuik, Kees

365

8.07 Electromagnetism II, Fall 2005  

E-Print Network [OSTI]

This course is the second in a series on Electromagnetism beginning with Electromagnetism I (8.02 or 8.022). It is a survey of basic electromagnetic phenomena: electrostatics; magnetostatics; electromagnetic properties of ...

Bertschinger, Edmund

366

High-frequency resonances in photorefractive crystals  

Science Journals Connector (OSTI)

Two-wave mixing in photorefractive materials is investigated for the case of applied dc electric fields and large detuning frequencies and for high-frequency alternating electric...

Grunnet-Jepsen, A; Aubrecht, I; Solymar, L

1995-01-01T23:59:59.000Z

367

An evaluation of genotoxicity in human neuronal-type cells subjected to oxidative stress under an extremely low frequency pulsed magnetic field  

Science Journals Connector (OSTI)

Abstract The possible genotoxicity of extremely low frequency magnetic field (ELF-MF) exposure is still a controversial topic. The most of the reported data suggests that it alone does not affect DNA integrity, but several recent reports have suggested that sinusoidal ELF-MF may increase the effect of known genotoxic agents. Only a few studies deal with non sinusoidal ELF-MF, including pulsed magnetic field (PMF), which are produced by several devices. The aim of this study is to investigate whether PMF exposure can interfere with DNA damage and repair in the presence of a genotoxic oxidative agent in neuronal type cells. To this purpose gamma-H2AX foci formation, which is a sensitive marker of DNA double strand breaks (DSB), was investigated at different points of time (1, 24, 48, 72h) after the H2O2 treatment (300?M for 1h) under PMF exposure (1mT, 50Hz) in human neuroblastoma BE(2)C cells. Moreover, cytotoxicity evaluation, by MTT assay and cell cycle analysis, was performed at various points of time after the treatment. Taken together, results suggest that PMF exposure does not interfere with genotoxicity and cytotoxicity induced by oxidative stress.

Gianfranco Giorgi; Mariangela Lecciso; Miriam Capri; Stella Lukas Yani; Angela Virelli; Ferdinando Bersani; Brunella Del Re

2014-01-01T23:59:59.000Z

368

Electromagnetic Wave Dynamics in  

E-Print Network [OSTI]

possibilities for strong localization of electromagnetic radiation in a dense and ultracold atomic gas sample an ultracold atomic rubidium gas sample, showing the coherent backscattering cone. The angular width of electrical excita- tion of condensed samples.3 Ongoing experimental and theoretical research directed toward

369

Electromagnetism and Gravitation  

E-Print Network [OSTI]

The classical concept of "mass density" is not fundamental to the quantum theory of matter. Therefore, mass density cannot be the source of gravitation. Here, we treat electromagnetic energy, momentum, and stress as its source. The resulting theory predicts that the gravitational potential near any charged elementary particle is many orders of magnitude greater than the Newtonian value.

Kenneth Dalton

1997-03-10T23:59:59.000Z

370

Electromagnetic pulsar spindown  

E-Print Network [OSTI]

We evaluate the result of the recent pioneering numerical simulations in Spitkovsky~2006 on the spindown of an oblique relativistic magnetic dipole rotator. Our discussion is based on our experience from two idealized cases, that of an aligned dipole rotator, and that of an oblique split-monopole rotator. We conclude that the issue of electromagnetic pulsar spindown may not have been resolved yet.

I. Contopoulos

2007-01-10T23:59:59.000Z

371

Electromagnetic wave propagation through an overdense magnetized collisional plasma layer  

SciTech Connect (OSTI)

The results of investigations into the feasibility of using a magnetic window to propagate electromagnetic waves through a finite-sized overdense plasma slab are described. We theoretically calculate the transmission coefficients for right- and left-handed circularly polarized plane waves through a uniform magnetized plasma slab. Using reasonable estimates for the plasma properties expected to be found in the ionized shock layer surrounding a hypersonic aircraft traveling in the earth's upper atmosphere (radio blackout conditions), and assuming a 1 GHz carrier frequency for the radio communications channel, we find that the required magnetic field for propagation of right-handed circularly polarized, or whistler, waves is on the order of a few hundred gauss. Transmission coefficients are calculated as a function of sheath thickness and are shown to be quite sensitive to the electron collision frequency. One-dimensional particle-in-cell simulations are shown to be in good agreement with the theory. These simulations also demonstrate that Ohmic heating of the electrons can be considerable. Two- and three-dimensional particle-in-cell simulations using a simplified waveguide and antenna model illustrate the same general transmission behavior as the theory and one-dimensional simulations. In addition, a net focusing effect due to the plasma is also observed in two and three dimensions. These simulations can be extended to design and analyze more realistic waveguide and antenna models.

Thoma, C.; Rose, D. V.; Miller, C. L.; Clark, R. E.; Hughes, T. P. [Voss Scientific LLC, Albuquerque, New Mexico 87108 (United States)

2009-08-15T23:59:59.000Z

372

Electromagnetic fluctuation-induced interactions in randomly charged slabs  

E-Print Network [OSTI]

Randomly charged net-neutral dielectric slabs are shown to interact across a featureless dielectric continuum with long-range electrostatic forces that scale with the statistical variance of their quenched random charge distribution and inversely with the distance between their bounding surfaces. By accounting for the whole spectrum of electromagnetic field fluctuations, we show that this long-range disorder-generated interaction extends well into the retarded regime where higher-order Matsubara frequencies contribute significantly. This occurs even for highly clean samples with only a trace amount of charge disorder and shows that disorder effects can be important down to the nano scale. As a result, the previously predicted non-monotonic behavior for the total force between dissimilar slabs as a function of their separation distance is substantially modified by higher-order contributions, and in almost all cases of interest, we find that the equilibrium inter-surface separation is shifted to substantially larger values compared to predictions based solely on the zero-frequency component. This suggests that the ensuing non-monotonic interaction is more easily amenable to experimental detection. The presence of charge disorder in the intervening dielectric medium between the two slabs is shown to lead to an additional force that can be repulsive or attractive depending on the system parameters and can, for instance, wash out the non-monotonic behavior of the total force when the intervening slab contains a sufficiently large amount of disorder charges.

Vahid Rezvani; Jalal Sarabadani; Ali Naji; Rudolf Podgornik

2012-07-19T23:59:59.000Z

373

A method for calculating wide band electromagnetic interference from power line corona  

SciTech Connect (OSTI)

An algorithm for calculating electromagnetic interference from power line corona for a range of frequencies from 100 kHz to 30 MHz is demonstrated. It can be used for calculations at any distance or direction from the line. The algorithm incorporates an existing generation function which has been optimized by comparison to long term electromagnetic interference measurements.

Olsen, R.G. [Washington State Univ., Pullman, WA (United States). School of Electrical Engineering and Computer Science] [Washington State Univ., Pullman, WA (United States). School of Electrical Engineering and Computer Science; Schennum, S.D. [Gonzaga Univ., Spokane, WA (United States)] [Gonzaga Univ., Spokane, WA (United States)

1995-07-01T23:59:59.000Z

374

Printed diodes operating at mobile phone frequencies  

Science Journals Connector (OSTI)

...diagnostic devices, and rollable solar cells, to cite a few (6, 7...electronics Printed electronics Advantage or disadvantage High performance Low performance...including that of extracting energy from an electromagnetic field...

Antonio Facchetti

2014-01-01T23:59:59.000Z

375

Quantum field theoretical description for the reflectivity of graphene  

E-Print Network [OSTI]

We derive the polarization tensor of graphene at nonzero temperature in (2+1)-dimensional space-time. The obtained tensor coincides with the previously known one at all Matsubara frequencies, but, in contrast to it, admits analytic continuation to the real frequency axis satisfying all physical requirements. Using the obtained representation for the polarization tensor, we develope quantum field theoretical description for the reflectivity of graphene. The analytic asymptotic expressions for the reflection coefficients and reflectivities at low and high frequencies are derived for both independent polarizations of the electromagnetic field. The dependencies of reflectivities on the frequency and angle of incidence are investigated. Numerical computations using the exact expressions for the polarization tensor are performed and application regions for the analytic asymptotic results are determined.

Bordag, M; Mostepanenko, V M; Petrov, V M

2015-01-01T23:59:59.000Z

376

Electromagnetic Properties of the Early Universe  

E-Print Network [OSTI]

Detailed physical processes of magnetic field generation from density fluctuations in the pre-recombination era are studied. Solving Maxwell equations and the generalized Ohm's law, the evolutions of the net charge density, the electric current and the electromagnetic field are solved. Unlike most of previous works, we treat electrons and photons as separate components under the assumption of tight coupling. We find that generation of the magnetic field due to density fluctuations takes place only from the second order of both perturbation theory and the tight coupling approximation.

Keitaro Takahashi; Kiyotomo Ichiki; Naoshi Sugiyama

2008-05-29T23:59:59.000Z

377

Vibration Isolation using a Shunted Electromagnetic S. Behrens, A. J. Fleming, S. O. R. Moheimani  

E-Print Network [OSTI]

a base disturbance y. A low- frequency mass-spring-damper is often employed as a mechanical filter to the terminals of an electromagnetic coil, the relative mechanical velocity between the coil and magnet can

Fleming, Andrew J.

378

An approach to electromagnetism from the general relativity  

E-Print Network [OSTI]

Classical gravitation is so similar to the electrostatic that the possible unification has been investigated for many years. Although electromagnetism is formulated successfully by quantum field theory, this paper proposes a simple approach to describe the electromagnetism from the macroscopic perspective of general relativity. The hypothesis is based on two charged particles that cause disturbance energy sufficient to disrupt the space-time and explain approximately Maxwell's equations. Therefore, with such this simple idea, we suggest the possibility that the geometric relationship between electromagnetism and gravitation is not yet fully exhausted.

Robert Monjo i Agut

2013-12-02T23:59:59.000Z

379

Theory of electromagnetic fluctuations for magnetized multi-species plasmas  

SciTech Connect (OSTI)

Analysis of electromagnetic fluctuations in plasma provides relevant information about the plasma state and its macroscopic properties. In particular, the solar wind persistently sustains a small but detectable level of magnetic fluctuation power even near thermal equilibrium. These fluctuations may be related to spontaneous electromagnetic fluctuations arising from the discreteness of charged particles. Here, we derive general expressions for the plasma fluctuations in a multi-species plasma following arbitrary distribution functions. This formalism, which generalizes and includes previous works on the subject, is then applied to the generation of electromagnetic fluctuations propagating along a background magnetic field in a plasma of two proton populations described by drifting bi-Maxwellians.

Navarro, Roberto E., E-mail: roberto.navarro@ug.uchile.cl; Muoz, Vctor [Departamento de Fsica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile); Araneda, Jaime [Departamento de Fsica, Universidad de Concepcin, Concepcin 4070386 (Chile); Moya, Pablo S. [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States); Department of Physics, Catholic University of America, Washington, D. C. 20064 (United States); Vias, Adolfo F. [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States); Valdivia, Juan A. [Departamento de Fsica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile); Centro de Estudios Interdisciplinarios Bsicos y Aplicados en Complejidad, CEIBA complejidad, Bogot (Colombia)

2014-09-15T23:59:59.000Z

380

Progress In Electromagnetics Research, PIER 74, 119, 2007 ANALYSIS OF INTERACTION BETWEEN A  

E-Print Network [OSTI]

partially re-radiates, and partially dissipates within the FR body, eventually producing heat. Both re-radiated energy and heat loss in the FR depend on coupling between the FR and the electromagnetic field picks out energy from electromagnetic field at the ferromagnetic resonance. Thus the typical linewidth

Koledintseva, Marina Y.

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Fast dynamic force computation for electrostatic and electromagnetic conductors  

E-Print Network [OSTI]

interval. Hence ef- ficient and accurate simulation tools are required for calculation of electrostatic and electromagnetic forces. A. Electrostatic Conductors When a voltage is applied between two conductors, electrostatic charges are induced... Conductors Electromagnetic interactions gain importance in high performance and high power applications because the magnitude of electrostatic forces is limited by the applied voltage. A current carrying conductor produces a magnetic field around the con...

Koteeswaran, Prabhavathi

2005-02-17T23:59:59.000Z

382

Electromagnetic fields in planarly layered anisotropic media  

Science Journals Connector (OSTI)

......in the exploration. Anisotropic effects when measuring...Alternations of sandstone and shales may give reservoir anisotropies...in reservoir rocks. Anisotropic material properties...Conductivity anisotropy in shale-free sandstone, Petrophysics...antennas over stratified anisotropic media, Geophysics......

L. O. Lseth; B. Ursin

2007-07-01T23:59:59.000Z

383

Theory of electromagnetic stirring by AC fields  

Science Journals Connector (OSTI)

......which demand very high standards of purity. Again an...simulations can make use of standard methods. The most difficult...be carried out using standard hydrodynamic packages. The aim of this review is to provide a summary...mean circulation. The plan of the review is as follows......

A.D. SNEYD

1993-01-01T23:59:59.000Z

384

APPROXIMATION OF ELECTROMAGNETIC FIELDS: PART I ...  

E-Print Network [OSTI]

A generalized Green's theorem on H(curl; ?) is used in treating initial boundary value ... Energy estimates for the time-dependent problem are given. For.

2003-08-06T23:59:59.000Z

385

Electromagnetic Siegert states for periodic dielectric structures  

E-Print Network [OSTI]

The formalism of Siegert states to describe the resonant scattering in quantum theory is extended to the resonant scattering of electromagnetic waves on periodic dielectric arrays. The excitation of electromagnetic Siegert states by an incident wave packet and their decay is studied. The formalism is applied to develop a theory of coupled electromagnetic resonances arising in the electromagnetic scattering problem for two such arrays separated by a distance 2h (or, generally, when the physical properties of the scattering array depend on a real coupling parameter h). Analytic properties of Siegert states as functions of the coupling parameter h are established by the Regular Perturbation Theorem which is an extension the Kato-Rellich theorem to the present case. By means of this theorem, it is proved that if the scattering structure admits a bound state in the radiation continuum at a certain value of the coupling parameter h, then there always exist regions within the structure in which the near field can be amplified as much as desired by adjusting the value of h. This establishes a rather general mechanism to control and amplify optical nonlinear effects in periodically structured planar structures possessing a nonlinear dielectric susceptibility.

Friends R. Ndangali; Sergei V. Shabanov

2011-08-09T23:59:59.000Z

386

Banded electromagnetic stator core  

DOE Patents [OSTI]

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

Fanning, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1996-01-01T23:59:59.000Z

387

Banded electromagnetic stator core  

DOE Patents [OSTI]

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

Fanning, Alan W. (San Jose, CA); Gonzales, Aaron A. (San Jose, CA); Patel, Mahadeo R. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1994-01-01T23:59:59.000Z

388

Gravitation and Electromagnetism  

E-Print Network [OSTI]

The realms of gravitation, belonging to Classical Physics, and Electromagnetism, belonging to the Theory of the Electron and Quantum Mechanics have remained apart as two separate pillars, inspite of a century of effort by Physicists to reconcile them. In this paper it is argued that if we extend ideas of Classical spacetime to include in addition to non integrability non commutavity also, then such a reconcilation is possible.

B. G. Sidharth

2001-06-16T23:59:59.000Z

389

Fractional Electromagnetic Waves  

E-Print Network [OSTI]

In the present work we consider the electromagnetic wave equation in terms of the fractional derivative of the Caputo type. The order of the derivative being considered is 0 <\\gamma<1. A new parameter \\sigma, is introduced which characterizes the existence of the fractional components in the system. We analyze the fractional derivative with respect to time and space, for \\gamma = 1 and \\gamma = 1/2 cases.

J. F. Gmez; J. J. Rosales; J. J. Bernal; V. I. Tkach; M. Gua

2011-08-31T23:59:59.000Z

390

Banded electromagnetic stator core  

DOE Patents [OSTI]

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figs.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1996-06-11T23:59:59.000Z

391

Banded electromagnetic stator core  

DOE Patents [OSTI]

A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1994-04-05T23:59:59.000Z

392

Electromagnetic Perturbations in the Reconnecting Current Sheet in MRX  

SciTech Connect (OSTI)

Magnetic reconnection is a fundamental plasma process in which magnetic field lines break and reconnect, converting magnetic field energy into particle kinetic energy. Electromagnetic fluctuations, which may play a role in fast reconnection, are studied from both an experimental and theoretical standpoint. The waves, which are in the lower hybrid range of frequencies, may be produced by a plasma instability known as the oblique lower hybrid drift instability. When the electron drift velocity is large, the theory predicts coupling between whistler and acoustic waves in the ion frame that may lead to an instability in the vicinity of the current sheet. On the experimental side, an antenna placed in the Magnetic Reconnection Experiment (MRX) at the Princeton Plasma Physics Laboratory is used to apply perturbations, and their propagation characteristics are measured. Results from a 2mm diameter antenna indicate that any induced fluctuations are confined to the current sheet and are preferentially excited in the direction of electron flow within the layer. Preliminary data from a 2cm diameter antenna shows a wave propagating in the electron flow direction at the local electron drift velocity. Thus electron drift appears to play a crucial role in the appearance of fluctuations.

Dorfman, Seth; Ji, Hantao; Yamada, MasAki; Ren Yang; Gerhardt, Stefan; Kulsrud, Russell; McGeehan, Brendan; Wang Yansong [Princeton Plasma Physics Laboratory, Princeton NJ 08540 (United States)

2006-11-30T23:59:59.000Z

393

The Theory of Quantized Fields. IV  

Science Journals Connector (OSTI)

The principal development in this paper is the extension of the eigenvalue-eigenvector concept to complete sets of anticommuting operators. With the aid of this formalism we construct a transformation function for the Dirac field, as perturbed by an external source. This transformation function is enlarged to describe phase transformations and, when applied to the isolated Dirac field, yields the charge and energy-momentum eigenvalues and eigenfunctions. The transformation function describing the system in the presence of the source is then used as a generating function to construct the matrices of all ordered products of the field operators, for the isolated Dirac field. The matrices in the occupation number representation are exhibited with a classification that effectively employs a time-reversed description for negative frequency modes. The last section supplements III by constructing the matrices of all ordered products of the potential vector, for the isolated electromagnetic field.

Julian Schwinger

1953-12-01T23:59:59.000Z

394

Iterated finite-orbit Monte Carlo simulations with full-wave fields for modeling tokamak ion cyclotron resonance frequency wave heating experiments  

SciTech Connect (OSTI)

The five-dimensional finite-orbit Monte Carlo code ORBIT-RF[M. Choi et al., Phys. Plasmas 12, 1 (2005)] is successfully coupled with the two-dimensional full-wave code all-orders spectral algorithm (AORSA) [E. F. Jaeger et al., Phys. Plasmas 13, 056101 (2006)] in a self-consistent way to achieve improved predictive modeling for ion cyclotron resonance frequency (ICRF) wave heating experiments in present fusion devices and future ITER [R. Aymar et al., Nucl. Fusion 41, 1301 (2001)]. The ORBIT-RF/AORSA simulations reproduce fast-ion spectra and spatial profiles qualitatively consistent with fast ion D-alpha [W. W. Heidbrink et al., Plasma Phys. Controlled Fusion 49, 1457 (2007)] spectroscopic data in both DIII-D [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] and National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 41, 1435 (2001)] high harmonic ICRF heating experiments. This work verifies that both finite-orbit width effect of fast-ion due to its drift motion along the torus and iterations between fast-ion distribution and wave fields are important in modeling ICRF heating experiments.

Choi, M.; Chan, V. S.; Lao, L. L.; Pinsker, R. I. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Green, D.; Berry, L. A.; Jaeger, F.; Park, J. M. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States); Heidbrink, W. W.; Liu, D.; Podesta, M. [University of California-Irvine, Irvine, California 92697 (United States); Harvey, R. [CompX, P.O. Box 2672, Del Mar, California 92014-5672 (United States); Smithe, D. N. [Tech-X Corporation, Boulder, Colorado 80303 (United States); Bonoli, P. [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2010-05-15T23:59:59.000Z

395

Generalized Terminal Modeling of Electromagnetic Interference  

SciTech Connect (OSTI)

Terminal models have been used for various applications. In this paper, a three-terminal model is proposed for electromagnetic-interference (EMI) characterization. The model starts with a power electronic system at a particular operating condition and creates a unique linearized equivalent circuit. Impedances and current/voltage sources define the noise throughout the entire EMI frequency spectrum. All parameters needed to create the model are clearly defined to ensure convergence and maximize accuracy. In addition, the accuracy of the model is confirmed up to 100 MHz for a dc-dc boost converter using both simulation and experimental validation.

Baisden, Andrew Carson [IEEE Industrial Applications Society; Boroyevich, Dushan [Virginia Polytechnic Institute and State University (Virginia Tech); Wang, Fei [ORNL

2010-01-01T23:59:59.000Z

396

Quantum mechanical constraints on the measurement of the density of the electromagnetic energy  

E-Print Network [OSTI]

It is considered constraints imposed by the quantum mechanics on the measurement of the density of the electromagnetic energy. First, the energy of the electromagnetic wave and the volume (time) are bound with the Heisenberg uncertainty principle. It reduces from double to ordinary the relativistic effect for the density of the electromagnetic energy. Second, the frequency of photons and the number of photons are bound with the Heisenberg uncertainty principle. Then relativistic effects for the frequency of photons and for the number of photons are incompatible.

D. L. Khokhlov

2004-02-05T23:59:59.000Z

397

ELECTROMAGNETIC COMPATIBILITY AND RENEWABLE POWER FOR IMPLANTABLE NEUROSTIMULATORS  

E-Print Network [OSTI]

J, Bakker P: Electromagnetic interference from radiomaking electromagnetic interference neurostimulator functioninclude electromagnetic interference and battery failure. In

Pantchenko, Oxana S.

2012-01-01T23:59:59.000Z

398

Electromagnetic analysis of nanostructure dispersion in polymer matrices  

E-Print Network [OSTI]

P. R. , Enhanced electromagnetic interference shielding40] Chung D. D. L. Electromagnetic Interference Shieldingreinforcement, electromagnetic interference shielding, etc.

Pfeifer, Steven Charles; Pfeifer, Steven Charles

2012-01-01T23:59:59.000Z

399

Electromagnetic Compatibility in Nuclear Power Plants  

SciTech Connect (OSTI)

Electromagnetic compatibility (EMC) has long been a key element of qualification for mission critical instrumentation and control (I&C) systems used by the U.S. military. The potential for disruption of safety-related I&C systems by electromagnetic interference (EMI), radio-frequency interference (RFI), or power surges is also an issue of concern for the nuclear industry. Experimental investigations of the potential vulnerability of advanced safety systems to EMI/RFI, coupled with studies of reported events at nuclear power plants (NPPs) that are attributed to EMI/RFI, confirm the safety significance of EMC for both analog and digital technology. As a result, Oak Ridge National Laboratory has been engaged in the development of the technical basis for guidance that addresses EMC for safety-related I&C systems in NPPs. This research has involved the identification of engineering practices to minimize the potential impact of EMI/RFI and power surges and an evaluation of the ambient electromagnetic environment at NPPs to tailor those practices for use by the nuclear industry. Recommendations for EMC guidance have been derived from these research findings and are summarized in this paper.

Ewing, P.D.; Kercel, S.W.; Korsah, K.; Wood, R.T.

1999-08-29T23:59:59.000Z

400

Electromagnetic Probes in PHENIX  

E-Print Network [OSTI]

Electromagnetic probes are arguably the most universal tools to study the different physics processes in high energy hadron and heavy ion collisions. In this paper we summarize recent measurements of real and virtual direct photons at central rapidity by the PHENIX experiment at RHIC in p+p, d+Au and Au+Au collisions. We also discuss the impact of the results and the constraints they put on theoretical models. At the end we report on the immediate as well as on the mid-term future of photon measurements at RHIC.

Gabor David

2006-09-21T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Electromagnetic pump stator coil  

DOE Patents [OSTI]

An electrical stator coil for an electromagnetic pump includes a continuous conductor strip having first and second terminals at opposite ends thereof and an intermediate section disposed therebetween. The strip is configured in first and second coil halves, with the first coil half including a plurality of windings extending from the first terminal to the intermediate section, and the second coil half including a plurality of windings extending from the second terminal to the intermediate section. The first and second coil halves are disposed coaxially, and the first and second terminals are disposed radially inwardly therefrom with the intermediate section being disposed radially outwardly therefrom. 9 figs.

Fanning, A.W.; Dahl, L.R.

1996-06-25T23:59:59.000Z

402

Entanglement of two-qubit photon beam by magnetic field  

E-Print Network [OSTI]

We have studied the possibility of affecting the entanglement measure of 2-qubit system consisting of two photons with different fixed frequencies but with two arbitrary linear polarizations, moving in the same direction, by the help of an applied external magnetic field. The interaction between the magnetic field and the photons in our model is achieved through intermediate electrons that interact with both the photons and the magnetic field. The possibility of exact theoretical analysis of this scheme is based on known exact solutions that describe the interaction of an electron subjected to an external magnetic field (or a medium of electrons not interacting with each other) with a quantized field of two photons. We adapt these exact solutions to the case under consideration. Using explicit wave functions for the resulting electromagnetic field, we calculate the entanglement measure of the photon beam as a function of the applied magnetic field and parameters of the electron medium.

A. D. Levin; D. M. Gitman; R. C. Castro

2014-05-15T23:59:59.000Z

403

Overview Of Electromagnetic Methods Applied In Active Volcanic Areas Of  

Open Energy Info (EERE)

Of Electromagnetic Methods Applied In Active Volcanic Areas Of Of Electromagnetic Methods Applied In Active Volcanic Areas Of Western United States Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Overview Of Electromagnetic Methods Applied In Active Volcanic Areas Of Western United States Details Activities (7) Areas (2) Regions (0) Abstract: A better understanding of active volcanic areas in the United States through electromagnetic geophysical studies received foundation from the many surveys done for geothermal exploration in the 1970's. Investigations by governmental, industrial, and academic agencies include (but are not limited to) mapping of the Cascades. Long Valley/Mono area, the Jemez volcanic field, Yellowstone Park, and an area in Colorado. For one example - Mt. Konocti in the Mayacamas Mountains, California - gravity,

404

Theory of shear suppression of edge turbulence by externally driven radio-frequency waves  

Science Journals Connector (OSTI)

Here, we propose and analyze a technique for active suppression of tokamak edge turbulence. Suppression occurs due to the effects of a sheared radial electric field generated by externally driven radio-frequency waves. Plasma flow is induced by radially varying wave-driven Reynolds and magnetic stresses, and opposed by neoclassical damping. For Alfvnic flow drive, the predicted shear flow profile is determined by ion inertia and electron dissipation effects. Results indicate that a modest amount of absorbed power is required for edge-turbulence suppression. More generally, several novel results in the theory of momentum transport by electromagnetic fluctuations are presented.

G. G. Craddock and P. H. Diamond

1991-09-16T23:59:59.000Z

405

Electromagnetic couplings of elementary vector particles  

E-Print Network [OSTI]

On the basis of the three fundamental principles of (i) Poincar\\'{e} symmetry of space time, (ii) electromagnetic gauge symmetry, and (iii) unitarity, we construct an universal Lagrangian for the electromagnetic interactions of elementary vector particles, i.e., massive spin-1 particles transforming in the /1/2,1/2) representation space of the Homogeneous Lorentz Group (HLG). We make the point that the first two symmetries alone do not fix the electromagnetic couplings uniquely but solely prescribe a general Lagrangian depending on two free parameters, here denoted by \\xi and g. The first one defines the electric-dipole and the magnetic-quadrupole moments of the vector particle, while the second determines its magnetic-dipole and electric-quadrupole moments. In order to fix the parameters one needs an additional physical input suited for the implementation of the third principle. As such, one chooses Compton scattering off a vector target and requires the cross section to respect the unitarity bounds in the high energy limit. In result, we obtain the universal g=2, and \\xi=0 values which completely characterize the electromagnetic couplings of the considered elementary vector field at tree level. The nature of this vector particle, Abelian versus non-Abelian, does not affect this structure. Merely, a partition of the g=2 value into non-Abelian, g_{na}, and Abelian, g_{a}=2-g_{na}, contributions occurs for non-Abelian fields with the size of g_{na} being determined by the specific non-Abelian group appearing in the theory of interest, be it the Standard Model or any other theory.

M. Napsuciale; S. Rodriguez; E. G. Delgado-Acosta; M. Kirchbach

2007-11-27T23:59:59.000Z

406

ANTENNA RADIATION NEAR THE LOCAL PLASMA FREQUENCY BY LANGMUIR WAVE EIGENMODES  

SciTech Connect (OSTI)

Langmuir waves (LWs) in the solar wind are generated by electron beams associated with solar flares, interplanetary shock fronts, planetary bow shocks, and magnetic holes. In principle, LWs localized as eigenmodes of density fluctuations can emit electromagnetic (EM) radiation by an antenna mechanism near the local plasma frequency f{sub p} and twice the local plasma frequency. In this work, analytic expressions are derived for the radiated electric and magnetic fields and power generated near f{sub p} by LW eigenmodes. The EM wave power emitted near f{sub p} is predicted as a function of the eigenmode length scale L, maximum electric field, driving electron beam speed, and the ambient plasma density and temperature. The escape to a distant observer of f{sub p} radiation from a localized Langmuir eigenmode is also briefly explored as a function of the plasma conditions.

Malaspina, David M. [Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303 (United States); Cairns, Iver H. [School of Physics, University of Sydney, New South Wales 2006 (Australia); Ergun, Robert E., E-mail: David.Malaspina@lasp.colorado.edu, E-mail: cairns@physics.usyd.edu.au, E-mail: ree@lasp.colorado.edu [Laboratory for Atmospheric and Space Physics, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80303 (United States)

2012-08-10T23:59:59.000Z

407

Electromagnetic fuel injector  

SciTech Connect (OSTI)

This patent describes an electromagnetic fuel injector for an internal combustion engine having a valve axis and including a housing, a flat armature connected to a movable valve element arranged to cooperate with a valve seat, spring means for exerting a force in an axial direction on the armature, and electromagnetic means for exerting a force in an opposite direction on the armature when electrically energized. The improvement comprises: the spring means being a helical coil spring disposed in substantially coaxial alignment with the valve axis and having an end in compressive engagement with the armature, the final coil which includes the end of the coil spring being inclined axially outward at an angle relative to a plane normal to the axis of the spring so as to apply to the armature a greater axial spring force to one side of the valve axis than the other thereby to effect pivoting of the armature about a pivot, the pivot being determined by the location of the end of the coil spring.

Gieseking, J.H.

1987-04-28T23:59:59.000Z

408

Controlled Source Frequency-Domain Electromagnetics At Neal Hot...  

Open Energy Info (EERE)

efforts. Software provided by Zonge International was used for the interpretation process. Interpretations show that the production fault dips west and trends north-south and...

409

Anomalous electron heat transport driven by low frequency electromagnetic turbulence  

SciTech Connect (OSTI)

We consider the anomalous electron and heat transport in a tokamak plasma. The electrons are described by the nonlinear drift-kinetic equation. We analyze transport through the averaged response function in the presence of drift-Alfven wave turbulence. In contrast to recent findings by Terry, Diamond, and Hahm, we conclude that magnetic fluctuations lead to a substantial transport of both parallel and perpendicular energies. The latter, previously neglected, is found to be significant and of the order of the test-particle diffusion.

Thoul, A.A.; Similon, P.L.; Sudan, R.N.

1987-09-28T23:59:59.000Z

410

Electromagnetics in characterizations  

E-Print Network [OSTI]

(cont.) Characterization of the differential guided mode of a coupled-strip transmission line allows us to understand its behaviors in high frequency circuit applications. S-parameters of the differential mode of a ...

Wu, Bae-Ian, 1975-

2003-01-01T23:59:59.000Z

411

Electromagnetic neutrino: a short review  

E-Print Network [OSTI]

A short review on selected issues related to the problem of neutrino electromagnetic properties is given. After a flash look at the theoretical basis of neutrino electromagnetic form factors, constraints on neutrino magnetic moments and electric millicharge from terrestrial experiments and astrophysical observations are discussed. We also focus on some recent studies of the problem and on perspectives.

Alexander I. Studenikin

2014-11-09T23:59:59.000Z

412

A fast multigrid-based electromagnetic eigensolver for curved metal boundaries on the Yee mesh  

SciTech Connect (OSTI)

For embedded boundary electromagnetics using the DeyMittra (Dey and Mittra, 1997) [1] algorithm, a special graddiv matrix constructed in this work allows use of multigrid methods for efficient inversion of Maxwells curlcurl matrix. Efficient curlcurl inversions are demonstrated within a shift-and-invert Krylov-subspace eigensolver (open-sourced at ([ofortt]https://github.com/bauerca/maxwell[cfortt])) on the spherical cavity and the 9-cell TESLA superconducting accelerator cavity. The accuracy of the DeyMittra algorithm is also examined: frequencies converge with second-order error, and surface fields are found to converge with nearly second-order error. In agreement with previous work (Nieter et al., 2009) [2], neglecting some boundary-cut cell faces (as is required in the time domain for numerical stability) reduces frequency convergence to first-order and surface-field convergence to zeroth-order (i.e. surface fields do not converge). Additionally and importantly, neglecting faces can reduce accuracy by an order of magnitude at low resolutions.

Bauer, Carl A., E-mail: carl.bauer@colorado.edu [Department of Physics and the Center for Integrated Plasma Studies, University of Colorado, Boulder, CO 80309 (United States); Werner, Gregory R. [Department of Physics and the Center for Integrated Plasma Studies, University of Colorado, Boulder, CO 80309 (United States)] [Department of Physics and the Center for Integrated Plasma Studies, University of Colorado, Boulder, CO 80309 (United States); Cary, John R. [Department of Physics and the Center for Integrated Plasma Studies, University of Colorado, Boulder, CO 80309 (United States) [Department of Physics and the Center for Integrated Plasma Studies, University of Colorado, Boulder, CO 80309 (United States); Tech-X Corporation, Boulder, CO 80303 (United States)

2013-10-15T23:59:59.000Z

413

Airborne electromagnetic surveys as a reconnaissance technique...  

Open Energy Info (EERE)

Airborne electromagnetic surveys as a reconnaissance technique for geothermal exploration Abstract INPUT airborne electromagnetic (AEM) surveys were conducted during 1979 in five...

414

Through-Barrier Electromagnetic Communication and Sensing: Advances in  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Through-Barrier Electromagnetic Communication and Sensing: Advances in Through-Barrier Electromagnetic Communication and Sensing: Advances in Wideband Radio-Wave Communications and ..... Speaker(s): Farid Dowla Date: June 1, 2007 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Mary Ann Piette (Complete seminar title is: Through-Barrier Electromagnetic Communication and Sensing: Advances in Wideband Radio-Wave Communications and Radar Imaging, Radio-Frequency (RF) Tags and Tera-Hertz (THz) Standoff Detection Spectroscopy) In many remote sensing problems there is a critical need to detect and image objects through barriers, such as buildings, with high reliability and resolution and at long ranges. A related problem is the wireless communication and geolocation of transceivers in harsh RF environments, such as in urban areas and underground caves, where

415

QUICKSILVER - a general tool for electromagnetic PIC simulation  

SciTech Connect (OSTI)

The dramatic increase in computational capability that has occurred over the last ten years has allowed fully electromagnetic simulations of large, complex, three-dimensional systems to move progressively from impractical, to expensive, and recently, to routine and widespread. This is particularly true for systems that require the motion of free charge to be self-consistently treated. The QUICKSILVER electromagnetic Particle-In-Cell (EM-PIC) code has been developed at Sandia National Laboratories to provide a general tool to simulate a wide variety of such systems. This tool has found widespread use for many diverse applications, including high-current electron and ion diodes, magnetically insulated power transmission systems, high-power microwave oscillators, high-frequency digital and analog integrated circuit packages, microwave integrated circuit components, antenna systems, radar cross-section applications, and electromagnetic interaction with biological material. This paper will give a brief overview of QUICKSILVER and provide some thoughts on its future development.

Seidel, D.B.; Coats, R.S.; Johnson, W.A. [and others

1996-10-01T23:59:59.000Z

416

THE BIANCHI IDENTITIES, ELECTROMAGNETIC WAVES, AND CHARGE CONSERVATION IN THE P(4) THEORY OF  

E-Print Network [OSTI]

OF GRAVITATION AND ELECTROMAGNETISM J. H. Chilton and K. S. Hammon Department of Physics North Carolina State, namely the affine geometry of the P(4) = O(1, 3) R4 theory of gravitation and electromag- netism (Norris) theory one obtains a conservation law and a wave equation for the electromagnetic field that parallels

Norris, Larry K.

417

Range-gated field disturbance sensor with range-sensitivity compensation  

DOE Patents [OSTI]

A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudorandomly modulated so that bursts in the sequence of bursts have a phase which varies. 8 figs.

McEwan, T.E.

1996-05-28T23:59:59.000Z

418

National High Magnetic Field Laboratory Audio Dictionary: Magnetic...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Links Magnets from Mini to Mighty Meet the Magnets How to Make an Electromagnet (audio slideshow) Compasses in Magnetic Fields (interactive tutorial) Magnetic Field Around a...

419

Impulsive cylindrical gravitational wave: one possible radiative form emitted from cosmic strings and corresponding electromagnetic response  

E-Print Network [OSTI]

The cosmic strings(CSs) may be one important source of gravitational waves(GWs), and it has been intensively studied due to its special properties such as the cylindrical symmetry. The CSs would generate not only usual continuous GW, but also impulsive GW that brings more concentrated energy and consists of different GW components broadly covering low-, intermediate- and high-frequency bands simultaneously. These features might underlie interesting electromagnetic(EM) response to these GWs generated by the CSs. In this paper, with novel results and effects, we firstly calculate the analytical solutions of perturbed EM fields caused by interaction between impulsive cylindrical GWs (would be one of possible forms emitted from CSs) and background celestial high magnetic fields or widespread cosmological background magnetic fields, by using rigorous Einstein - Rosen metric. Results show: perturbed EM fields are also in the impulsive form accordant to the GW pulse, and asymptotic behaviors of the perturbed EM fields are fully consistent with the asymptotic behaviors of the energy density, energy flux density and Riemann curvature tensor of corresponding impulsive cylindrical GWs. The analytical solutions naturally give rise to the accumulation effect which is proportional to the term of distance^1/2, and based on it, we for the first time predict potentially observable effects in region of the Earth caused by the EM response to GWs from the CSs.

H. Wen; F. Y. Li; Z. Y. Fang; A. Beckwith

2014-05-04T23:59:59.000Z

420

MajoranaOppenheimer Approach to Maxwell Electrodynamics. Part III. Electromagnetic Spherical Waves in Spaces of Constant Curvature  

Science Journals Connector (OSTI)

Complex formalism of RiemannSilbersteinMajoranaOppenheimer in Maxwell electrodynamics extended to the case...D-functions. In the case of compact Riemann model a discrete frequency spectrum for electromagnetic ...

E. M. Ovsiyuk; V. M. Redkov; N. G. Tokarevskaya

2013-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Electromagnetic wave scattering by small bodies  

E-Print Network [OSTI]

A reduction of the Maxwell's system to a Fredholm second-kind integral equation with weakly singular kernel is given for electromagnetic (EM) wave scattering by one and many small bodies. This equation is solved asymptotically as the characteristic size of the bodies tends to zero. The technique developed is used for solving the many-body EM wave scattering problem by rigorously reducing it to solving linear algebraic systems, completely bypassing the usage of integral equations. An equation is derived for the effective field in the medium, in which many small particles are embedded. A method for creating a desired refraction coefficient is outlined.

A. G. Ramm

2008-04-21T23:59:59.000Z

422

Study on technology of electromagnetic radiation of sensitive index to forecast the coal and gas hazards  

Science Journals Connector (OSTI)

Hazard forecast of coal and gas outburst was an important step of comprehensive outburst-prevention measures. Aiming at the manifestation of disaster threatens such as the gas outburst to mine safety, this paper explained the forecasting principles of electromagnetic radiation to coal and gas outburst, by the electromagnetic radiation theory of coal rock damage; it studied the characteristics and rules of electromagnetic radiation during the deformation and fracture process of loaded coal rocks, and confirmed forecast sensitive indexes of electromagnetic radiation as well as its critical values by signals of electromagnetic radiation. By applying EMR monitoring technology in the field, outburst prediction and forecast tests to the characteristics of electromagnetic radiation during the driving process was taken, and figured out the hazard prediction values by using forecast methods of static and dynamic trend.

Yuliang Wu; Wen Li

2010-01-01T23:59:59.000Z

423

Analysis of Ocean Electromagnetic Data Using a Hilbert Spectrum Approach  

Science Journals Connector (OSTI)

We apply a newly developed time series analysis technique the Hilbert?Huang Transform (HHT) to naturally occurring ocean electromagnetic data obtained from bottom?mounted sensors. The HHT was originally developed as an alternative to the Fourier power spectral density for the analysis of nonlinear phenomena in water waves. The HHT is applied to the data in two steps. In the first step an empirical mode decomposition is used to extract individual oscillatory modes possessing different characteristic time scales. Unlike Fourier modes however these modes can vary in amplitude and frequency. In the second step the Hilbert transform is used to determine physically meaningful instantaneous frequencies from these modes. We present results showing that the HHT provides a more compact representation of the ocean electromagnetic environment than the Fourier spectrum. In particular the HHT is able to capture nonlinear wave phenomena associated with ocean swell in a single mode without the need for higher order harmonics.

Jeffrey Ridgway; Michael L. Larsen; Cye H. Waldman; Michael Gabbay; Rodney R. Buntzen; C. David Rees

2003-01-01T23:59:59.000Z

424

Controlled-source electromagnetic survey at Soda Lakes geothermal area, Nevada  

SciTech Connect (OSTI)

The EM-60 system, a large-moment frequency-domain electromagnetic loop prospecting system, was operated in the Soda Lakes geothermal area, Nevada. Thirteen stations were occupied at distances ranging from 0.5-3.0 km from two transmitter sites. These yielded four sounding curves--the normalized amplitudes and phases of the vertical and radial magnetic fields as a function of frequency--at each station. In addition, two polarization ellipse parameters, ellipticity and tilt angle, were calculated at each frequency. The data were interpreted by means of a least-squares inversion procedure which fits a layered resistivity model to the data. A three-layer structure is indicated, with a near-surface 20 ohm-m layer of 100-400 m thickness, a middle 2 ohm-m layer of approximately 1 km thickness, and a basement of greater than 10 ohm-m. The models indicate a northwesterly structural strike; the top and middle layers seem to thicken from northeast to southwest. The results agree quite well with previous results of dipole-dipole and magnetotelluric (MT) surveys. The EM-60 survey provided greater depth penetration (1 to 1.5 km) than dipole-dipole, but MT far surpassed both in its depth of exploration. One advantage of EM in this area is its ease and speed of operation. Another advantage, its relative insensitivity to lateral inhomogeneities, is not as pronounced here as it would be in areas of more complex geology.

Stark, M.; Wilt, M.; Haught, J.R.; Goldstein, N.

1980-07-01T23:59:59.000Z

425

Novel microwave near-field sensors for material characterization, biology, and nanotechnology  

E-Print Network [OSTI]

The wide range of interesting electromagnetic behavior of contemporary materials requires that experimentalists working in this field master many diverse measurement techniques and have a broad understanding of condensed matter physics and biophysics. Measurement of the electromagnetic response of materials at microwave frequencies is important for both fundamental and practical reasons. In this paper, we propose a novel near-field microwave sensor with application to material characterization, biology, and nanotechnology. The sensor is based on a subwavelength ferrite-disk resonator with magnetic-dipolar-mode (MDM) oscillations. Strong energy concentration and unique topological structures of the near fields originated from the MDM resonators allow effective measuring material parameters in microwaves, both for ordinary structures and objects with chiral properties.

Joffe, R; Shavit, R

2015-01-01T23:59:59.000Z

426

NISTHB 150-11 Electromagnetic  

E-Print Network [OSTI]

Programs Dennis Camell Electromagnetics Division Physical Measurement Laboratory http://dx.doi.org/10 of the NVLAP term, logo, and symbol. #12;NIST Handbook 150-11:2013 iii Contents Foreword ............................................................................................................................1 1.1 Scope of handbook

427

Generation and coherent control of even-order harmonics driven by intense frequency-comb and cavity-mode fields inside a fsEC  

E-Print Network [OSTI]

Generation and coherent control of even-order harmonics driven by intense frequency-comb and cavity) doi:10.1088/0953-4075/46/14/145403 Generation and coherent control of even-order harmonics driven, resulting in the generation of even-order harmonics. The high-order harmonic generation (HHG) from a two

Chu, Shih-I

428

ELECTROMAGNETIC PROPERTIES OF THE DAYEM BRIDGE M. T. LEVINSEN  

E-Print Network [OSTI]

ELECTROMAGNETIC PROPERTIES OF THE DAYEM BRIDGE M. T. LEVINSEN Physics Laboratory I, H. C. Abstract. 2014 The first measurements on the Dayem bridge showed that the behaviour in an applied microwave field was quite different from that of the Josephson tunnel junction. Measure- ments on bridges one

Boyer, Edmond

429

Black Hole Thermodynamics and Electromagnetism  

E-Print Network [OSTI]

We show a strong parallel between the Hawking, Beckenstein black hole Thermodynamics and electromagnetism: When the gravitational coupling constant transform into the electromagnetic coupling constant, the Schwarzchild radius, the Beckenstein temperature, the Beckenstein decay time and the Planck mass transform to respectively the Compton wavelength, the Hagedorn temperature, the Compton time and a typical elementary particle mass. The reasons underlying this parallalism are then discussed in detail.

Burra G. Sidharth

2005-07-15T23:59:59.000Z

430

Electromagnetic Calorimeter for HADES  

E-Print Network [OSTI]

We propose to build the Electromagnetic calorimeter for the HADES di-lepton spectrometer. It will enable to measure the data on neutral meson production from nucleus-nucleus collisions, which are essential for interpretation of dilepton data, but are unknown in the energy range of planned experiments (2-10 GeV per nucleon). The calorimeter will improve the electron-hadron separation, and will be used for detection of photons from strange resonances in elementary and HI reactions. Detailed description of the detector layout, the support structure, the electronic readout and its performance studied via Monte Carlo simulations and series of dedicated test experiments is presented. The device will cover the total area of about 8 m^2 at polar angles between 12 and 45 degrees with almost full azimuthal coverage. The photon and electron energy resolution achieved in test experiments amounts to 5-6%/sqrt(E[GeV]) which is sufficient for the eta meson reconstruction with S/B ratio of 0.4% in Ni+Ni collisions at 8 AGeV. A purity of the identified leptons after the hadron rejection, resulting from simulations based on the test measurements, is better than 80% at momenta above 500 MeV/c, where time-of-flight cannot be used.

W. Czyzycki; E. Epple; L. Fabbietti; M. Golubeva; F. Guber; A. Ivashkin; M. Kajetanowicz; A. Krasa; F. Krizek; A. Kugler; K. Lapidus; E. Lisowski; J. Pietraszko; A. Reshetin; P. Salabura; Y. Sobolev; J. Stanislav; P. Tlusty; T. Torrieri; M. Traxler

2011-11-28T23:59:59.000Z

431

Electromagnetic Calorimeter for HADES  

E-Print Network [OSTI]

We propose to build the Electromagnetic calorimeter for the HADES di-lepton spectrometer. It will enable to measure the data on neutral meson production from nucleus-nucleus collisions, which are essential for interpretation of dilepton data, but are unknown in the energy range of planned experiments (2-10 GeV per nucleon). The calorimeter will improve the electron-hadron separation, and will be used for detection of photons from strange resonances in elementary and HI reactions. Detailed description of the detector layout, the support structure, the electronic readout and its performance studied via Monte Carlo simulations and series of dedicated test experiments is presented. The device will cover the total area of about 8 m^2 at polar angles between 12 and 45 degrees with almost full azimuthal coverage. The photon and electron energy resolution achieved in test experiments amounts to 5-6%/sqrt(E[GeV]) which is sufficient for the eta meson reconstruction with S/B ratio of 0.4% in Ni+Ni collisions at 8 AGeV....

Czyzycki, W; Fabbietti, L; Golubeva, M; Guber, F; Ivashkin, A; Kajetanowicz, M; Krasa, A; Krizek, F; Kugler, A; Lapidus, K; Lisowski, E; Pietraszko, J; Reshetin, A; Salabura, P; Sobolev, Y; Stanislav, J; Tlusty, P; Torrieri, T; Traxler, M

2011-01-01T23:59:59.000Z

432

Immunizing digital systems against electromagnetic interference  

SciTech Connect (OSTI)

This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant`s electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Secondly, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced.

Ewing, P.D.; Korsah, K. [Oak Ridge National Lab., TN (United States); Antonescu, C. [Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research

1993-02-01T23:59:59.000Z

433

Immunizing digital systems against electromagnetic interference  

SciTech Connect (OSTI)

This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Secondly, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced.

Ewing, P.D.; Korsah, K. (Oak Ridge National Lab., TN (United States)); Antonescu, C. (Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research)

1993-01-01T23:59:59.000Z

434

Electromagnetic soundings over a geothermal reservoir in Dixie Valley, Nevada  

SciTech Connect (OSTI)

An electromagnetic (EM) sounding survey was performed over a region encompassing the Dixie Valley geothermal field with the purpose of mapping the subsurface resistivity in the geothermal field and its surroundings. The EM survey consisted of 19 frequency-domain depth soundings made with the EM-60 system using three separate horizontal-loop transmitters, and was designed to explore a narrow region adjacent to the Stillwater Range to a depth of 2 to 3 k. Most sounding curves could be fitted to three-layer resistivity models. The surface layer is moderately conductive (10 to 15 ohm-m), has a maximum thickness of 500 m, and consists mainly of alluvial fan and lake sediments. More conductive zones are associated with hydrothermally altered rocks; a resistivity high may be associated with siliceous hot spring deposits. The conductive second layer (2 to 5 ohm-m) varies in thickness from 400 to 800 m and thickens toward the center of the valley. This layer probably consists of lacustrine sediments saturated with saline waters. Local resistivity lows observed in the second layer may be related to elevated subsurface temperatures. This layer may act as a cap rock for the geothermal system. Resistivities of the third layer are high (50 to 100 ohm-m) except in a narrow 5-km band paralleling the range front. This low-resistivity zone, within volcanic rocks, correlates well in depth and location with reported zones of geothermal fluid production. It also seems to correlate with the western margin of a concealed graben structure previously inferred from other geophysical data.

Wilt, M.J.; Goldstein, N.E.

1983-04-01T23:59:59.000Z

435

Gene Frequency  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Gene Frequency Gene Frequency Name: donna Location: N/A Country: N/A Date: N/A Question: If six fingers is a dominant human trait why do we have only five? Replies: This is simple. There are just not many genes in the human population for six fingers. Steve Sample Look in any high school biology book for what is known as Hardy-Weinberg equilibrium. These two scientists (separately) said that gene frequencies do not change much unless something in the environment selects them over other genes. In other words, unless 6 fingers somehow becomes an advantage, and five-fingered people have less of an advantage, the frequency of six fingered people in the population will not necessarily increase. This is the same reason that recessive traits don't disappear from the population. Also, six fingers is not considered attractive and they may not get as many mates. Also, more people are born with six fingers than you might imagine but just have them amputated shortly after birth.

436

Spontaneous and Nitrosourea-induced Primary Tumors of the Central Nervous System in Fischer 344 Rats Exposed to Frequency-modulated Microwave Fields  

Science Journals Connector (OSTI)

...were 750 pups for distribution into the final...G. Z.). In planning this study, a...fields (25) . Energy absorption levels...modeling verified by electric probe measurements...anionic charge distribution on strands of glycoprotein...fields with absorbed energies below 5 W/kg...

W. Ross Adey; Craig V. Byus; Christopher D. Cain; Robert J. Higgins; Robert A. Jones; Charles J. Kean; Niels Kuster; Anne MacMurray; Robert B. Stagg; and Grenith Zimmerman

2000-04-01T23:59:59.000Z

437

Graded pitch electromagnetic pump for thin strip metal casting systems  

DOE Patents [OSTI]

A metal strip casing system is provided with an electromagnetic pump which includes a pair of primary blocks having a graded pole pitch, polyphase ac winding and being arranged on opposite sides of a movable heat sink. A nozzle is provided for depositing liquid metal on the heat sink such that the resulting metal strip and heat sink combination is subjected to a longitudinal electromagnetic field which increases in wavelength in the direction of travel of the heat sink, thereby subjecting the metal and heat sink to a longitudinal force having a magnitude which increases in the direction of travel. 4 figs.

Kuznetsov, S.B.

1986-04-01T23:59:59.000Z

438

Electromagnetic low-energy constants in ChPT  

E-Print Network [OSTI]

We investigate three-flavour chiral perturbation theory including virtual photons in a limit where the strange quark mass is much larger than the external momenta and the up and down quark masses, and where the external fields are those of two-flavour chiral perturbation theory. In particular we work out the strange quark mass dependence of the electromagnetic two-flavour low-energy constants C and k_i. We expect that these relations will be useful for a more precise determination of the electromagnetic low-energy constants.

Christoph Haefeli; Mikhail A. Ivanov; Martin Schmid

2007-10-29T23:59:59.000Z

439

Analog Electromagnetism in a Symmetrized $^3$He-A  

E-Print Network [OSTI]

We derive a low temperature effective action for the order parameter in a symmetrized phase A of helium 3, where the Fermi velocity equals the transversal velocity of low energy fermionic quasiparticles. The effective action has a form of the electromagnetic action. This analog electromagnetism is a part of the program to derive analog gravity and the standard model as a low energy effective theory in a condensed matter system. For the analog gauge field to satisfy the Maxwell equations interactions in $^3$He require special tuning that leads to the symmetric case.

Jacek Dziarmaga

2001-12-18T23:59:59.000Z

440

Steven Weinberg, Weak Interactions, and Electromagnetic Interactions  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Steven Weinberg and Steven Weinberg and Weak and Electromagnetic Interactions Resources with Additional Information Steven Weinberg Courtesy Dr. Steven Weinberg Steven "Weinberg is a professor of physics and astronomy at UT [The University of Texas] Austin and is founding director of the Theory Group in the College of Natural Sciences. [He is] well known for his development of a field theory that unifies the electromagnetic and weak nuclear forces, and for other major contributions to physics and cosmology ... Weinberg's work has been honored with numerous prizes, including the Nobel Prize in Physics in 1979 and the National Medal of Science in 1991. Weinberg is the author of the prize-winning book The First Three Minutes: A Modern View of the Origin of the Universe (which has been translated into 22 foreign languages) as well as Gravitation and Cosmology, The Discovery of Subatomic Particles, Dreams of a Final Theory and The Quantum Theory of Fields. ... Weinberg was the recipient of the Scientist as Poet prize from Rockefeller University for "extraordinary achievements in conveying - with passionate clarity - the ideas, history, explanatory power and aesthetic dimensions of fundamental physics." The citation mentioned two of Weinberg's books.

Note: This page contains sample records for the topic "frequency electromagnetic fields" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Plasmon decay to a neutrino pair via neutrino electromagnetic moments in a strongly magnetized medium  

E-Print Network [OSTI]

We calculate the neutrino luminosity of a degenerate electron gas in a strong magnetic field via plasmon decay to a neutrino pair due to neutrino electromagnetic moments and obtain the relative upper bounds on the effective neutrino magnetic moment.

A. V. Borisov; P. E. Sizin

2014-06-12T23:59:59.000Z

442

Radiation and Propagation of SLF/ELF Electromagnetic Waves of Space Borne Transmitter  

Science Journals Connector (OSTI)

In Chap.7, we will summarize our recent works on the radiation of an electric dipole in infinite anisotropic plasma and the electromagnetic field on the sea surface generated by the space borne transmitter in SLF

Prof. Weiyan Pan; Dr. Kai Li

2014-01-01T23:59:59.000Z

443

Elimination of Radio-Frequency Noise by Identifying and Diverting Large RF Ground Currents  

SciTech Connect (OSTI)

The problem of electromagnetic interference in scientific instruments is compounded for high-power plasma experiments by the large currents and voltages as well as by the broad bandwidths of the instruments. Ground loops are known to allow stray magnetic fields to drive large ground currents that can induce spurious signals and damage electronics. Furthermore, even when a ground loop is broken, capacitive coupling can still permit the flow of radio-frequency current, resulting in high-frequency spurious signals that can overwhelm the desired signal. We present the effects of RF ground loops on the output of vacuum photodiodes used in the Caltech Solar Loop Experiment and demonstrate the elimination of the spurious signals by diverting the ground currents away from the most vulnerable point of the signal line. Techniques for identifying the RF ground loops are also discussed. These techniques should be valuable in many high-power systems where interference from spurious coupling is an issue.

Perkins, R. J.; Bellan, P. M. [Applied Physics, California Institute of Technology (United States)

2011-12-23T23:59:59.000Z

444

String loops oscillating in the field of Kerr black holes as a possible explanation of twin high-frequency quasiperiodic oscillations observed in microquasars  

E-Print Network [OSTI]

Small oscillations of current-carrying string loops around stable equilibrium positions corresponding to minima of the effective potential in the equatorial plane of the Kerr black holes are studied using the perturbation method. In the lowest approximation, two uncoupled harmonic oscillators are obtained that govern the radial and vertical oscillations; the higher-order terms determine non-linear phenomena and transition to chaotic motion through quasi-periodic stages of the oscillatory motion. The radial profiles of frequencies of the radial and vertical harmonic oscillations that are relevant also in the quasi-periodic stages of the oscillatory motion are given, and their properties in dependence on the spin of the black holes and the angular momentum and tension of the string loops are determined. It is shown that the radial profiles differ substantially from those corresponding to the radial and vertical frequencies of the geodetical epicyclic motion; however, they have the same mass-scaling and their ma...

Stuchlk, Zden?k

2014-01-01T23:59:59.000Z

445

Self-consistent electrodynamics of large-area high-frequency capacitive plasma discharge  

SciTech Connect (OSTI)

Capacitively coupled plasmas (CCPs) generated using high frequency (3-30 MHz) and very high frequency (30-300 MHz) radio-frequency (rf) sources are used for many plasma processing applications including thin film etching and deposition. When chamber dimensions become commensurate with the effective rf wavelength in the plasma, electromagnetic wave effects impose a significant influence on plasma behavior. Because the effective rf wavelength in plasma depends upon both rf and plasma process conditions (e.g., rf power and gas pressure), a self-consistent model including both the rf power delivery system and the plasma discharge is highly desirable to capture a more complete physical picture of the plasma behavior. A three-dimensional model for self-consistently studying both electrodynamic and plasma dynamic behavior of large-area (Gen 10, >8 m{sup 2}) CCP is described in this paper. This model includes Maxwell's equations and transport equations for charged and neutral species, which are coupled and solved in the time domain. The complete rf plasma discharge chamber including the rf power delivery subsystem, rf feed, electrodes, and the plasma domain is modeled as an integrated system. Based on this full-wave solution model, important limitations for processing uniformity imposed by electromagnetic wave propagation effects in a large-area CCP (3.05x2.85 m{sup 2} electrode size) are studied. The behavior of H{sub 2} plasmas in such a reactor is examined from 13.56 to 200 MHz. It is shown that various rectangular harmonics of electromagnetic fields can be excited in a large-area rectangular reactor as the rf or power is increased. The rectangular harmonics can create not only center-high plasma distribution but also high plasma density at the corners and along the edges of the reactor.

Chen Zhigang; Rauf, Shahid; Collins, Ken [Applied Materials, Inc., 974 E. Arques Avenue, Sunnyvale, California 94085 (United States)

2010-10-15T23:59:59.000Z

446

Random walk of electrons in a gas in the presence of polarized electromagnetic waves: Genesis of a wave induced discharge  

SciTech Connect (OSTI)

The average number of collisions N of seed electrons with neutral gas atoms during random walk in escaping from a given volume, in the presence of polarized electromagnetic waves, is found to vary as N=B({lambda}/{lambda}){sup 2}/[1+C({lambda}/{lambda})]{sup 2}, indicating a modification to the conventional field free square law N=A({lambda}/{lambda}){sup 2}, where {lambda} is the characteristic diffusion length and {lambda} the mean free path. It is found that for the field free case A=1.5 if all the electrons originate at the center and is 1.25 if they are allowed to originate at any random point in the given volume. The B and C coefficients depend on the wave electric field and frequency. Predictions of true discharge initiation time {tau}{sub c} can be made from the temporal evolution of seed electrons over a wide range of collision frequencies. For linearly polarized waves of 2.45 GHz and electric field in the range (0.6-1.0)x10{sup 5} V/m, {tau}{sub c}=5.5-1.6 ns for an unmagnetized microwave driven discharge at 1 Torr argon.

Bhattacharjee, Sudeep; Paul, Samit [Department of Physics, Indian Institute of Technology, Kanpur 208016 (India)

2009-10-15T23:59:59.000Z

447

High-frequency self-aligned graphene transistors with transferred gate stacks  

Science Journals Connector (OSTI)

...2009 ) Radio-frequency electrical...Epitaxial-graphene RF field-effect...2011 ) High-frequency, scaled graphene...of high-frequency measurement...Information (PDF) High-frequency self-aligned...attention for radio-frequency transistor...

Rui Cheng; Jingwei Bai; Lei Liao; Hailong Zhou; Yu Chen; Lixin Liu; Yung-Chen Lin; Shan Jiang; Yu Huang; Xiangfeng Duan

2012-01-01T23:59:59.000Z

448

On the electromagnetic constitutive laws that are equivalent to spacetime metrics  

E-Print Network [OSTI]

The raising of both indices in the components of the Minkowski electromagnetic field strength 2-form to give the components of the electromagnetic excitation bivector field can be regarded as being equivalent to an electromagnetic constitutive law, as well as being defined by the components of the spacetime metric. This notion is clarified, and the nature of the equivalent dielectric tensors and magnetic permeability tensors that are defined by some common spacetime metrics is discussed. The relationship of the basic construction to effective metrics is discussed, and, in particular, the fact that this effective metric is more general than the Gordon metric.

D. H. Delphenich

2014-09-17T23:59:59.000Z

449

Surface electromagnetic wave equations in a warm magnetized quantum plasma  

SciTech Connect (OSTI)

Based on the single-fluid plasma model, a theoretical investigation of surface electromagnetic waves in a warm quantum magnetized inhomogeneous plasma is presented. The surface electromagnetic waves are assumed to propagate on the plane between a vacuum and a warm quantum magnetized plasma. The quantum magnetohydrodynamic model includes quantum diffraction effect (Bohm potential), and quantum statistical pressure is used to derive the new dispersion relation of surface electromagnetic waves. And the general dispersion relation is analyzed in some special cases of interest. It is shown that surface plasma oscillations can be propagated due to quantum effects, and the propagation velocity is enhanced. Furthermore, the external magnetic field has a significant effect on surface wave's dispersion equation. Our work should be of a useful tool for investigating the physical characteristic of surface waves and physical properties of the bounded quantum plasmas.

Li, Chunhua; Yang, Weihong [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Wu, Zhengwei, E-mail: wuzw@ustc.edu.cn [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Center of Low Temperature Plasma Application, Yunnan Aerospace Industry Company, Kunming, 650229 Yunnan (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2014-07-15T23:59:59.000Z

450

Combined gravitational and electromagnetic self-force on charged particles in electrovac spacetimes  

E-Print Network [OSTI]

We consider the self-force on a charged particle moving in a curved spacetime with a background electromagnetic field, extending previous studies to situations in which gravitational and electromagnetic perturbations are comparable. The formal expression $f^{ret}_\\alpha$ for the self-force on a particle, written in terms of the retarded perturbed fields, is divergent, and a renormalization is needed to find the particle's acceleration at linear order in its mass $m$ and charge $e$. We assume that, as in previous work in a Lorenz gauge, the renormalization for accelerated motion comprises an angle average and mass renormalization. Using the short distance expansion of the perturbed electromagnetic and gravitational fields, we show that the renormalization is equivalent to that obtained from a mode sum regularization in which one subtracts from the expression for the self-force in terms of the retarded fields a singular part field comprising only the leading and subleading terms in the mode sum. The most striking part of our result, arising from a remarkable cancellation, is that the renormalization involves no mixing of electromagnetic and gravitational fields. In particular, the renormalized mass is obtained by subtracting (1) the purely electromagnetic contribution from a point charge moving along an accelerated trajectory and (2) the purely gravitational contribution from a point mass moving along the same trajectory. In a mode-sum regularization, the same cancellation implies that the required regularization parameters are sums of their purely electromagnetic and gravitational values.

Thomas M. Linz; John L. Friedman; Alan G. Wiseman

2014-06-19T23:59:59.000Z

451

Initial Results of Multi-Frequency Electron Cyclotron Heating in the Levitated Dipole  

E-Print Network [OSTI]

Initial Results of Multi-Frequency Electron Cyclotron Heating in the Levitated Dipole Experiment A electromagnet via multiple-frequency electron cyclotron resonance heating (ECRH). Multiple frequency ECRH will be presented. Keywords: dipole confinement, electron cyclotron heating, superconducting magnet PACS: 52.25.Xz

452

Electromagnetic compatibility in semiconductor manufacturing  

SciTech Connect (OSTI)

Electromagnetic Interference (EMI) causes problems in semiconductor manufacturing facilities that range from nuisances to major disruptions of production. In many instances, these issues are addressed in a reactionary rather than proactive manner by individuals who do not have the experience or the equipment necessary to combat EMI problems in a timely, cost effective manner. This approach leads to expensive retrofits, reduced equipment availability, long recovery times, and in some cases, line yield impacts. The goal of electromagnetic compatibility (EMC) in semiconductor manufacturing is to ensure that semiconductor process, metrology, and support equipment operate as intended without being affected by electromagnetic disturbances either transmitted through air (radiated interference), or transferred into the equipment via a conductive media (conducted interference). Rather than being neglected until serious issues arise, EMC should be considered in the early stages of facility design, in order to gain the most benefit at the lowest cost.

Montoya, J.A. [Intel Corp., Hillsboro, OR (United States)

1995-12-31T23:59:59.000Z

453

Perfectly Reflectionless Omnidirectional Electromagnetic Absorber  

E-Print Network [OSTI]

We demonstrate the existence of metamaterial blueprints describing, and fundamental limitations concerning, perfectly reflectionless omnidirectional electromagnetic absorbers (PR-OEMA). Previous attempts to define PR-OEMA blueprints have led to active (gain), rather than passive, media. We explain this fact and unveil new, distinct limitations of true PR-OEMA devices including the appearance of an "electromagnetic horizon" on physical solutions. As practical alternatives, we introduce two new OEMA blueprints. While these two blueprints do not correspond to reflectionless media, they are effective in absorbing incident waves in a manner robust to incident wave diversity.

Sainath, Kamalesh

2014-01-01T23:59:59.000Z

454

Electromagnetic Behavior of the Vortex Sponge  

Science Journals Connector (OSTI)

In an introductory paper the vortex sponge was shown to be governed in restricted cases by Maxwell's free-space equations. In the present paper analogs to electric and magnetic energies and Poynting's theorem are derived by simple mechanical considerations. Rotational stability suggested originally by MacCullagh as a fundamental property of a luminiferous ether turns out to be a quality of the medium as do the stresses introduced by Faraday and Maxwell to explain the mechanical actions of electric and magnetic fields. A rudimentary model for the electrostatic field is suggested on this basis. A conventional definition of charge and the laws of Coulomb and Biot complete Maxwell's equations for cases including charges and currents. A model of the magnetic field based on the bulk rotation and the Faraday-Maxwell stresses combined with the laws of Coulomb and Biot permits the inference of the Lorentz force. Although numerous gaps occur in the treatment it seems not unlikely that the vortex sponge has the qualities described by the electromagnetic field equations as well as the mechanical attributes required for a model of these fields.

Edward M. Kelly

1964-01-01T23:59:59.000Z

455

High-Frequency Electrostatic Plasma Instabilities  

Science Journals Connector (OSTI)

A description of the stability properties of a plasma under the influence of an external electric field oscillating near the plasma frequency is presented.

J. P. Freidberg and B. M. Marder

1971-10-01T23:59:59.000Z

456

High-frequency, high-intensity photoionization  

Science Journals Connector (OSTI)

Two analytical methods for computing ionization by high-frequency fields are compared. Predicted ionization rates compare well, but energy predictions for the onset of ionization...

Reiss, H R

1996-01-01T23:59:59.000Z

457

Printed diodes operating at mobile phone frequencies  

Science Journals Connector (OSTI)

...disposable diagnostic devices, and rollable solar cells, to cite a few (6, 7), which...for given devices (Table 1). The main obstacle to the realization of this technology...functions, including that of extracting energy from an electromagnetic field to provide...

Antonio Facchetti

2014-01-01T23:59:59.000Z

458

INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS  

SciTech Connect (OSTI)

Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. However, not all pipelines can be inspected with current systems that move inside the pipeline propelled by the product flow. Inspection platforms that crawl slowly inside a pipeline are being developed to maneuver past the physical barriers that limit inspection. Battelle is building innovative electromagnetic sensors for pipeline crawlers. The various sensor types will assess a wide range of pipeline anomalies including corrosion, mechanical damage, cracking and seam weld defects. An implementation of two electromagnetic sensors were designed and tested. A pulsed eddy current system that uses sensors to measure the decay of induced eddy currents to establish the wall thickness has excellent potential. The results of experiments are comparable with magnetic flux leakage detecting 10% metal loss steps following a monotonic increase in signal strength. A rotating permanent remote field eddy current exciter was designed and built to produce strong signal levels at the receiver and reduce power consumption. Midway through the development of each technology, both sensor systems have produced results that warrant further development.

J. Bruce Nestleroth

2004-05-01T23:59:59.000Z

459

On the mechanism of electromagnetic microwave absorption in superfluid helium  

SciTech Connect (OSTI)

In experiments on electromagnetic (EM) wave absorption in the microwave range in superfluid (SF) helium [1-3], a narrow EM field absorption line with a width on the order of (20-200) kHz was observed against the background of a wide absorption band with a width of 30-40 GHz at frequencies f{sub 0} Almost-Equal-To 110-180 GHz corresponding to the roton gap energy {Delta}{sub r}(T) in the temperature range 1.4-2.2 K. Using the so-called flexoelectric mechanism of polarization of helium atoms ({sup 4}He) in the presence of density gradients in SF helium (HeII), we show that nonresonance microwave absorption in the frequency range 170-200 GHz can be due to the existence of time-varying local density gradients produced by roton excitations in the bulk HeII. The absorption bandwidth is determined by the roton-roton scattering time in an equilibrium Boltzmann gas of rotons, which is t{sub r-r} Almost-Equal-To 3.4 Multiplication-Sign 10{sup -11} s at T = 1.4 K and decreases upon heating. We propose that the anomalously narrow microwave resonance absorption line in HeII at the roton frequency f{sub 0}(T) = {Delta}r(T)/2{pi}h appears due to the following two factors: (i) the discrete structure of the spectrum of the surface EM resonator modes in the form of a periodic sequence of narrow peaks and (ii) the presence of a stationary dipole layer in HeII near the resonator surface, which forms due to polarization of {sup 4}He atoms under the action of the density gradient associated with the vanishing of the density of the SF component at the solid wall. For this reason, the relaxation of nonequilibrium rotons generated in such a surface dipole layer is strongly suppressed, and the shape and width of the microwave resonance absorption line are determined by the roton density of states, which has a sharp peak at the edge of the roton gap in the case of weak dissipation. The effective dipole moments of rotons in the dipole layer can be directed either along or across the normal to the resonator surface, which explains the experimentally observed symmetric doublet splitting of the resonance absorption line in an external dc electric field perpendicular to the resonator surface. We show that negative absorption (induced emission) of EM field quanta observed after triggering a Kapitza 'heat gun' occurs when the occupation numbers for roton states due to 'pumping' of rotons exceed the occupation numbers of EM field photons in the resonator.

Pashitskii, E. A., E-mail: pashitsk@iop.kiev.ua; Pentegov, V. I. [National Academy of Sciences of Ukraine, Institute of Physics (Ukraine)

2012-08-15T23:59:59.000Z

460

Questions and Answers - I am creating an electromagnet for my school's  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Do you know whatan electromagnet is? Do you know what<br>an electromagnet is? Previous Question (Do you know what an electromagnet is?) Questions and Answers Main Index Next Question (Why does adding coils to an electromagnet make it stronger?) Why does adding coils to anelectromagnet make it stronger? I am creating an electromagnet for my school's science fair project. Does the shape of the iron core make a difference? Is solid copper wire better than stranded wire? Is copper wire best, or is another wire better? Should the wire be insulated or bare? What can I do to get the most current out of a battery? Yes, the shape of the iron core does matter. The more complete the circuit formed by the iron, the more field that you will get for a given coil and current. The best way to do a simple magnet is to have an iron core shaped

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461

Electromagnetic design considerations for fast acting controllers  

SciTech Connect (OSTI)

Electromagnetic design considerations for fast acting controllers in a power system is introduced and defined. A distinction is made in relation to the more commonly understood system control design necessary for damping electromechanical oscillations using stability programs and eigenanalysis. Electromagnetic eigenanalysis tools have limited availability and are consequently rarely used. Electromagnetic transients programs (emtp) on the other hand are widely used and a procedure for undertaking electromagnetic control design of fast acting controllers in a power system using emtp is presented.

Woodford, D.A. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)] [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)

1996-07-01T23:59:59.000Z

462

IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 55, NO. 2, APRIL 2013 395 Electromagnetic Interference Analysis of  

E-Print Network [OSTI]

to electromagnetic interference (EMI) is becoming a critical aspect of signal integrity analysis. For mod- eling in high-speed packages [2]. As a result, effi- cient and accurate electromagnetic interference (EMIIEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 55, NO. 2, APRIL 2013 395 Electromagnetic

Roy, Sourajeet

463

Spherical Harmonic Series Solution for SLF/ELF Field in the EarthIonosphere Waveguide/Cavity  

Science Journals Connector (OSTI)

In Chap.3, the spherical harmonic series solutions are obtained for the SLF/ELF electromagnetic fields of vertical and horizontal ... series solutions. It is noted that the SLF/ELF electromagnetic field componen...

Prof. Weiyan Pan; Dr. Kai Li

2014-01-01T23:59:59.000Z

464

Electromagnetic Induced Gravitational Perturbations  

E-Print Network [OSTI]

We study the physical consequences of two diffferent but closely related perturbation schemes applied to the Einstein-Maxwell equations. In one case the starting space-time is flat while in the other case it is Schwarzschild. In both cases the perturbation is due to a combined electric and magnetic dipole field. We can see, within the Einstein-Maxwell equations a variety of physical consequences. They range from induced gravitational energy-momentum loss, to a well defined spin angular momentum with its loss and a center-of-mass with its equations of motion.

T. M. Adamo; E. T. Newman

2008-07-23T23:59:59.000Z

465

611: Electromagnetic Theory Problem Sheet 5  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 5 (1a) The Null Energy Condition on an energy = (k, 0, 0, k), show that the energy-momentum tensor Tµ = 1 4 Fµ F - 1 4µ F F (1) for electromagnetism if the equality kµ k Tµ = 0 is attained. (2) Show that the energy-momentum tensor for electromagnetism can

Pope, Christopher

466

Electromagnetic Interrogation of Dielectric Materials 1  

E-Print Network [OSTI]

Electromagnetic Interrogation of Dielectric Materials 1 H.T. Banks M.W. Buksas Center for Research grant P200A40730. #12; Abstract We investigate time domain based electromagnetic inverse problems electromagnetic phenomenon. For our purposes, we categorize the materials and the models employed to describe them

467

Electromagnetic Corrections in Staggered Chiral Perturbation Theory  

E-Print Network [OSTI]

Electromagnetic Corrections in Staggered Chiral Perturbation Theory C. Bernard and E.D. Freeland perturbation theory including electromagnetism, and discuss the extent to which quenched-photon simulations can-lat]17Nov2010 #12;Electromagnetic Corrections in Staggered Chiral Perturbation Theory E.D. Freeland 1

Bernard, Claude

468

Physics 4: Introductory Physics Electromagnetism and Light  

E-Print Network [OSTI]

Physics 4: Introductory Physics Electromagnetism and Light Professor Jeffrey D. Richman Department: Electromagnetism and Light Welcome to Physics 4! What is your goal in life? If it is to become an engineer or to pursue a career in science, this is a key class for you. Understanding electromagnetism and light

Fygenson, Deborah Kuchnir

469

Electromagnetic and nuclear radiation detector using micromechanical sensors  

DOE Patents [OSTI]

Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.

Thundat, Thomas G. (Knoxville, TN); Warmack, Robert J. (Knoxville, TN); Wachter, Eric A. (Oak Ridge, TN)

2000-01-01T23:59:59.000Z

470

Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount  

Open Energy Info (EERE)

Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount St Helens, Washington Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount St Helens, Washington Details Activities (1) Areas (1) Regions (0) Abstract: A very low frequency (VLF) electromagnetic induction survey in the crater of Mount St. Helens has identified several electrically conductive structures that appear to be associated with thermal anomalies and ground water within the crater. The most interesting of these conductive structures lies beneath the central dome. It is probably a partial melt of dacite similar to that comprising the June 1981 lobe of the central dome. Author(s): James N. Towle

471

Characterization of the coherent noise, electromagnetic compatibility and electromagnetic interference of the ATLAS EM calorimeter Front End Board  

E-Print Network [OSTI]

Characterization of the coherent noise, electromagnetic compatibility and electromagnetic interference of the ATLAS EM calorimeter Front End Board

Chase, B E; Lanni, F; Makowiecki, D S; Radeka, V; Rescia, S; Takai, H; Bn, J; Parsons, J; Sippach, W

1999-01-01T23:59:59.000Z

472

Ground Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

Ground Electromagnetic Techniques Ground Electromagnetic Techniques (Redirected from Ground Electromagnetic Methods) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Ground Electromagnetic Techniques Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electromagnetic Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water Thermal: Resistivity influenced by temperature

473

Definition: Electromagnetic Profiling Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Profiling Techniques Electromagnetic Profiling Techniques Jump to: navigation, search Dictionary.png Electromagnetic Profiling Techniques Electromagnetic profiling techniques map lateral variations in subsurface resistivity.[1] View on Wikipedia Wikipedia Definition Exploration geophysics is the applied branch of geophysics which uses surface methods to measure the physical properties of the subsurface Earth, along with the anomalies in these properties, in order to detect or infer the presence and position of ore minerals, hydrocarbons, geothermal reservoirs, groundwater reservoirs, and other geological structures. Exploration geophysics is the practical application of physical methods (such as seismic, gravitational, magnetic, electrical and electromagnetic) to measure the physical properties of rocks, and in particular, to detect

474

Electromagnetic Sounding Techniques | Open Energy Information  

Open Energy Info (EERE)

Electromagnetic Sounding Techniques Electromagnetic Sounding Techniques (Redirected from Electromagnetic Sounding Methods) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Electromagnetic Sounding Techniques Details Activities (1) Areas (1) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Ground Electromagnetic Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water

475

E-Print Network 3.0 - arbitrary magnetic field Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

magnetic field Search Powered by Explorit Topic List Advanced Search Sample search results for: arbitrary magnetic field Page: << < 1 2 3 4 5 > >> 1 Progress In Electromagnetics...

476

Questions and Answers - Which jobs use electromagnets?  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

does adding coils to anelectromagnet make it stronger? does adding coils to an<br>electromagnet make it stronger? Previous Question (Why does adding coils to an electromagnet make it stronger?) Questions and Answers Main Index Next Question (Why is a non-permanent, but long lasting, magnet called a permanent magnet?) Why is a non-permanent, but long lasting,magnet called a permanent magnet? Which jobs use electromagnets? In today's world almost all jobs other than a goat herder use some type of electromagnet. They are everywhere. Electric motors are a type of electromagnet. Cars have dozens of electromagnets that move things or generate electricity. There are all sorts of interesting applications for larger electromagnets. The most obvious and biggest example is electricity. There are some interesting applications like dumping shredded garbage

477

Electromagnetic Ion-Beam Instabilities in the Solar Wind  

Science Journals Connector (OSTI)

The stability of a plasma consisting of two, unequal, isotropic, ion beams streaming along a uniform magnetic field has been investigated by numerically solving the full electromagnetic, Vlasov, linear dispersion relation for high-? plasmas. Three instabilities are found: One is closely associated with the usual Alfvn mode and the two others with the "fast" or magnetosonic mode. The importance of these instabilities for certain neutral-beam-injection experiments and in the solar wind is emphasized.

Michael D. Montgomery; S. Peter Gary; D. W. Forslund; W. C. Feldman

1975-09-08T23:59:59.000Z

478

Electromagnetic Techniques | Open Energy Information  

Open Energy Info (EERE)

form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » Electromagnetic Techniques Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Electromagnetic Techniques Details Activities (0) Areas (0) Regions (0) NEPA(5) Exploration Technique Information Exploration Group: Geophysical Techniques Exploration Sub Group: Electrical Techniques Parent Exploration Technique: Electrical Techniques Information Provided by Technique Lithology: Rock composition, mineral and clay content Stratigraphic/Structural: Detection of permeable pathways, fracture zones, faults Hydrological: Resistivity influenced by porosity, grain size distribution, permeability, fluid saturation, fluid type and phase state of the pore water