Rectification of displacement currents in an adiabatic electron pump

2001 ◽  
Vol 63 (12) ◽  
Author(s):  
P. W. Brouwer
Keyword(s):  
Displacement Currents

Pump and displacement currents of reconstituted ATP synthase on black lipid membranes

1988 ◽  
Vol 104 (2) ◽  
pp. 179-191 ◽  
Author(s):  
B. Christensen ◽  
M. Gutweiler ◽  
E. Grell ◽  
N. Wagner ◽  
R. Pabst ◽  
...  
Keyword(s):  
Atp Synthase ◽  
Lipid Membranes ◽  
Black Lipid Membranes ◽  
Displacement Currents

On modeling a well casing for resistivity and induced polarization

Geophysics ◽  
1984 ◽  
Vol 49 (11) ◽  
pp. 2061-2063 ◽  
Author(s):  
James R. Wait
Keyword(s):  
Electrical Properties ◽  
Electric Dipole ◽  
Free Space ◽  
Eddy Currents ◽  
Interfacial Polarization ◽  
Induced Polarization ◽  
Mutual Impedance ◽  
The Earth ◽  
Horizontal Electric Dipole ◽  
Displacement Currents

In a previous communication I proposed an analytical model to simulate the electromagnetic (EM) and induced polarization (IP) response of a metal well casing (Wait, 1983). To facilitate the analysis, the earth was idealized as a homogeneous conducting half‐space of electrical properties (σ, ε, μ). The well casing was represented as a filamental vertical conductor of semiinfinite length that was characterized by a series axial impedance to account for eddy currents and interfacial polarization. A further basic simplification was to neglect displacement currents in the air; this was justified when all significant distances were small compared with the free‐space wavelength. Initially, the source was taken to be a horizontal electric dipole or current element I ds on the air‐earth interface. By integration of the results, the mutual impedance between two grounded circuits could be ascertained. In the absence of the vertical conductor (i.e., the well casing) the results reduced to those given by Sunde (1968) and Ward (1967).

scholarly journals Filamentary Alfvénic structures excited at the edges of equatorial plasma bubbles

2007 ◽  
Vol 25 (10) ◽  
pp. 2159-2165 ◽  
Author(s):  
R. Pottelette ◽  
M. Malingre ◽  
J. J. Berthelier ◽  
E. Seran ◽  
M. Parrot
Keyword(s):  
Alfven Waves ◽  
Alfvén Waves ◽  
Plasma Bubble ◽  
Plasma Bubbles ◽  
Wave Measurements ◽  
Demeter Satellite ◽  
Equatorial Plasma Bubbles ◽  
Background Magnetic Field ◽  
Gravity Driven ◽  
Displacement Currents

Abstract. Recent observations performed by the French DEMETER satellite at altitudes of about 710 km suggest that the generation of equatorial plasma bubbles correlates with the presence of filamentary structures of field aligned currents carried by Alfvén waves. These localized structures are located at the bubble edges. We study the dynamics of the equatorial plasma bubbles, taking into account that their motion is dictated by gravity driven and displacement currents. Ion-polarization currents appear to be crucial for the accurate description of the evolution of plasma bubbles in the high altitude ionosphere. During their eastward/westward motion the bubbles intersect gravity driven currents flowing transversely with respect to the background magnetic field. The circulation of these currents is prohibited by large density depressions located at the bubble edges acting as perfect insulators. As a result, in these localized regions the transverse currents have to be locally closed by field aligned currents. Such a physical process generates kinetic Alfvén waves which appear to be stationary in the plasma bubble reference frame. Using a two-dimensional model and "in situ" wave measurements on board the DEMETER spacecraft, we give estimates for the magnitude of the field aligned currents and the associated Alfvén fields.

Shallow subsurface mapping by electromagnetic sounding in the 300 kHz to 30 MHz range: Model studies and prototype system assessment

Geophysics ◽  
1994 ◽  
Vol 59 (8) ◽  
pp. 1201-1210 ◽  
Author(s):  
Duff C. Stewart ◽  
Walter L. Anderson ◽  
Thomas P. Grover ◽  
Victor F. Labson
Keyword(s):  
Dielectric Permittivity ◽  
High Frequency ◽  
Low Frequency ◽  
Computer Programs ◽  
Thin Layers ◽  
Depth Range ◽  
Frequency Range ◽  
Model Studies ◽  
New Instrument ◽  
Displacement Currents

A new instrument designed for frequency‐domain sounding in the depth range 0–10 m uses short coil spacings of 5 m or less and a frequency range of 300 kHz to 30 MHz. In this frequency range, both conduction currents (controlled by electrical conductivity) and displacement currents (controlled by dielectric permittivity) are important. Several surface electromagnetic survey systems commonly used (generally with frequencies less than 60 kHz) are unsuitable for detailed investigation of the upper 5 m of the earth or, as with ground‐penetrating radar, are most effective in relatively resistive environments. Most computer programs written for interpretation of data acquired with the low‐frequency systems neglect displacement currents, and are thus unsuited for accurate high‐frequency modeling and interpretation. New forward and inverse computer programs are described that include displacement currents in layered‐earth models. The computer programs and this new instrument are used to evaluate the effectiveness of shallow high‐frequency soundings based on measurement of the tilt angle and the ellipticity of magnetic fields. Forward model studies indicate that the influence of dielectric permittivity provides the ability to resolve thin layers, especially if the instrument frequency range can be extended to 50 MHz. Field tests of the instrument and the inversion program demonstrate the potential for detailed shallow mapping wherein both the resistivity and the dielectric permittivity of layers are determined. Although data collection and inversion are much slower than for low‐frequency methods, additional information is obtained inasmuch as there usually is a permittivity contrast as well as a resistivity contrast at boundaries between different materials. Determination of dielectric permittivity is particularly important for hazardous waste site characterization because the presence of some contaminants may have little effect on observed resistivity but a large effect on observed permittivity.

Natural-frequency concept utilized in remote probing of the earth

2003 ◽  
Vol 81 (4) ◽  
pp. 705-712 ◽  
Author(s):  
S T Bishay ◽  
O M Abo-Seida ◽  
G M Sami
Keyword(s):  
Natural Frequency ◽  
Analytical Form ◽  
Step Response ◽  
Earth Model ◽  
Induced Voltage ◽  
Diagnostic Features ◽  
Vertical Magnetic Dipole ◽  
Remote Probing ◽  
Displacement Currents ◽  
Layered Ground

The complete time-domain fields due to a vertical magnetic dipole on the surface of a two-layered earth model are derived in an analytical form using the natural-frequency concept. In these expressions, the displacement currents in the earth's layers are taken into consideration. The step responses of the induced voltage in a horizontal receiving loop is found to have definite diagnostic features for the ground beneath. These features are demonstrated by numerical results and shown by figures. The clear distinction between the step response of the homogeneous and the two-layered ground suggests that this response can be used for the detection of the stratification. PACS Nos.: 41.20.Jb, 42.25.Bs, 42.25.Gy, 44.05.+e

REPLY OF MESSRS I. D’ERCEVILLE AND G. KUNETZ TO THE DISCUSSION BY J. T. WEAVER

Geophysics ◽  
1963 ◽  
Vol 28 (3) ◽  
pp. 490-490
Author(s):  
I. d’Erceville ◽  
G. Kunetz
Keyword(s):  
Primary Field ◽  
Displacement Currents ◽  
Telluric Currents

The authors have read Mr. Weaver’s remarks with great interest. They would like to point out that their aim has not been to clear up the still debated question of how to define the primary field that generates the telluric currents, but to study the effect of a fault on a special type of field, complying with the laws of electromagnetism (neglecting the displacement currents, as is usual at the frequences considered) and differing little from actual telluric currents.

Influence of alcohol on mechanical and electrical properties of thin organic films

Open Physics ◽  
2007 ◽  
Vol 5 (3) ◽  
Author(s):  
Martin Kopáni ◽  
Martin Weis
Keyword(s):  
Electrical Properties ◽  
Conformational Changes ◽  
Structural Changes ◽  
Pure Water ◽  
Contactless Method ◽  
Dipalmitoyl Phosphatidylcholine ◽  
Mechanical And Electrical Properties ◽  
Methanol Solutions ◽  
The Stability ◽  
Displacement Currents

AbstractStability of organic materials properties is essential for further applications and was intensely investigated in last few decades. The aim of this study is to detect the structural changes of dipalmitoyl-phosphatidylcholine (DPPC) monolayer as a model system of organic material under influence of alcohols solutions. As subphases of monolayers (Langmuir films), pure water, ethanol and methanol solutions were used. For detection of changes in charge states of the molecules as well as relation with structural and conformational changes, a contactless method employing Maxwell’s displacement currents (MDC) was used. In DPPC monolayer on the subphase of methanol-water, a gradual absorption of methanol molecules into the layer can appear. In DPPC monolayer on the subphase of ethanol-water adsorption of ethanol molecules on the layer can be observed. Influence of alcohols results in a significant change of mechanical and electrical properties as well as in the stability of thin films.

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