NON-EQUILIBRIUM ELECTRICAL CONDUCTIVITY AND ELECTRON TEMPERATURE MEASUREMENTS IN ELECTRIC FIELDS AND CROSSED ELECTRIC AND MAGNETIC FIELDS

1965 ◽  
Author(s):  
G.C. BREDERLOW ◽  
R. HODGSON ◽  
W.T. RIEDMULLER
Keyword(s):  
Electrical Conductivity ◽  
Magnetic Fields ◽  
Electron Temperature ◽  
Electric Fields ◽  
Temperature Measurements ◽  
Electric And Magnetic Fields ◽  
Non Equilibrium

VARIATION OF ELECTRICAL CONDUCTIVITY WITH DEPTH BY THE MAGNETO‐TELLURIC METHOD

Geophysics ◽  
1960 ◽  
Vol 25 (5) ◽  
pp. 998-1008 ◽  
Author(s):  
E. R. Niblett ◽  
C. Sayn‐Wittgenstein
Keyword(s):  
Electrical Conductivity ◽  
Magnetic Fields ◽  
Surface Structure ◽  
Continuous Recording ◽  
Research Station ◽  
Electric And Magnetic Fields

Apparatus has been installed at the Dominion Observatory Research Station at Meanook, Alberta, for the continuous recording of earth potentials. The theory due to Cagniard (1953) and others, in which relative amplitudes of horizontal components of electric and magnetic fields are used to interpret the sub‐surface structure, is applied in a modified form, to data from the Meanook records. Values of electrical conductivity between depths of 10 km and 100 km are estimated, and found to vary roughly between [Formula: see text] and [Formula: see text] e.m.u.

A time‐domain EM system measuring the step response of the ground

Geophysics ◽  
1984 ◽  
Vol 49 (7) ◽  
pp. 1010-1026 ◽  
Author(s):  
G. F. West ◽  
J. C. Macnae ◽  
Y. Lamontagne
Keyword(s):  
Magnetic Fields ◽  
Impulse Response ◽  
Electric Fields ◽  
Time Domain ◽  
Wide Band ◽  
Step Response ◽  
System Function ◽  
Response Measurement ◽  
Resistivity Method ◽  
Electric And Magnetic Fields

A wide‐band time‐domain EM system, known as UTEM, which uses a large fixed transmitter and a moving receiver has been developed and used extensively in a variety of geologic environments. The essential characteristics that distinguish it from other systems are that its system function closely approximates a stepfunction response measurement and that it can measure both electric and magnetic fields. Measurement of step rather than impulse response simplifies interpretation of data amplitudes, and improves the detection of good conductors in the presence of poorer ones. Measurement of electric fields provides information about lateral conductivity contrasts somewhat similar to that obtained by the gradient array resistivity method.

Hall Currents and the Ejection of Prominences by Sunspots

1949 ◽  
Vol 2 (1) ◽  
pp. 39
Author(s):  
RG Giovanelli
Keyword(s):  
Magnetic Fields ◽  
Electric Fields ◽  
Magnetic Force ◽  
Large Space ◽  
Space Charges ◽  
Surrounding Atmosphere ◽  
Electric And Magnetic Fields ◽  
Order Of Magnitude ◽  
General Movement ◽  
Set Up

During the growth of sunspots induced electric fields may be expected to be set up in the surrounding atmosphere. It is shown that, because of the comparatively low conductivity perpendicular to lines of magnetic force, there are localized regions where large space charges occur, resulting in large electric fields perpendicular to the lines of magnetic force. Consequently both positive and negative charges drift in the same sense in a direction which is at right angles to the electric and magnetic fields, giving rise to a general movement of the gas. The drift velocities are difficult to estimate, but appear to be of the order of magnitude of those found in eruptive prominences.

Elastic Constants of Nematic Liquid Crystals

1972 ◽  
Vol 27 (6) ◽  
pp. 966-976 ◽  
Author(s):  
Hans Gruler ◽  
Terry J. Scheffer ◽  
Gerhard Meier
Keyword(s):  
Magnetic Fields ◽  
Electric Fields ◽  
Detailed Comparison ◽  
Theoretical Treatment ◽  
Electrical Capacitance ◽  
Normal Deformation ◽  
Electric And Magnetic Fields ◽  
The Magnetic Field ◽  
Dynamic Phenomena ◽  
Good Agreement

Abstract We present a theoretical treatment and give experimental observations of the deformation that occurs in a nematic liquid crystal when electric or magnetic fields are applied. We consider only normal deformations in the nematic material where fluid flow and other dynamic phenomena play no role. Three important sample geometries are considered in the magnetic field, and the experimentally observed deformations are in good agreement with theory. The normal deformation induced by electric fields is of interest from a device standpoint, and we give a solution for the deformation that is valid even for large dielectric anisotropics. This solution has been experimentally verified. We give a detailed comparison of the distortions produced by electric and magnetic fields and show that the deformations are of a similar form even though the field is nonuniform in the electric case. The change in birefringence and electrical capacitance as a function of distortion is discussed as a means of observing the deformation.

scholarly journals Mathematical Modelling of Electric and Magnetic Fields of Main Pipelines Cathodic Protection in Electrically Anisotropic Media

2021 ◽  
Vol 225 ◽  
pp. 04002
Author(s):  
Vladimir Krizsky ◽  
Pavel Aleksandrov ◽  
Alexey Kovalskii ◽  
Sergey Viktorov
Keyword(s):  
Mathematical Model ◽  
Electrical Conductivity ◽  
Magnetic Fields ◽  
Electrochemical Corrosion ◽  
Azimuth Angle ◽  
Specific Electrical Conductivity ◽  
Main Pipeline ◽  
Main Pipelines ◽  
Electric And Magnetic Fields ◽  
Angle Of Rotation

A mathematical model is constructed and computational experiments are performed to study the effect of anisotropy of the specific electrical conductivity of the soil on the distribution of electric and magnetic fields generated by cathodic electrochemical corrosion protection stations of the underground main pipeline (MP). The variation of electric and magnetic fields depending on the azimuth angle of rotation of the specific electrical conductivity tensor of the soil containing the pipeline is analysed.

scholarly journals Влияние магнитных и электрических полей на динамику образования плазмоидов в гатчинском разряде

2022 ◽  
Vol 92 (3) ◽  
pp. 366
Author(s):  
Shixin Zhao ◽  
Chengxun Yuan ◽  
А.А. Кудрявцев ◽  
Jingfeng Yao ◽  
Г.Д. Шабанов
Keyword(s):  
Magnetic Fields ◽  
Electric Fields ◽  
Electric Charge ◽  
Active Phase ◽  
Ball Lightning ◽  
Electric And Magnetic Fields ◽  
Direction Of Movement

The behavior in magnetic and electric fields of the Gatchina discharge, which is used mainly to create an analog of ball lightning in the laboratory in a normal atmosphere, is analyzed. Shown that in these studies it is possible to determine the sign of an uncompensated electric charge as in the active phase of the discharge, and in the forming long-lived luminous formations. Also shown that electric and magnetic fields can change the direction of movement of the forming luminous formation and even completely block its formation. The type and mechanism of existence firework ball lightning are considered, photos of which are presented in widely known monographs on the ball lightning.

scholarly journals Dynamics of electric and magnetic fields in case of the urban environment

2021 ◽  
Vol 265 ◽  
pp. 02001
Author(s):  
Vladimir I. Sturman ◽  
Alyona N. Loginovskaya ◽  
Anastasiya A. Dolganova ◽  
Mihail V. Shirokov
Keyword(s):  
Electrical Conductivity ◽  
Magnetic Fields ◽  
Transmission Lines ◽  
Indirect Effects ◽  
Temporal Dynamics ◽  
Weather Conditions ◽  
Line Frequency ◽  
Saint Petersburg ◽  
Electric And Magnetic Fields

This paper studies the temporal dynamics of power-line frequency electric and magnetic fields in Saint-Petersburg and environs. It is found that electromagnetic fields generated by high-voltage transmission lines (HVTL) constantly change, depending on their loading and weather conditions. The dependence on weather conditions involves both the direct effect of air electrical conductivity as a function of its humidity, and indirect effects including the dependence of energy consumption on temperature and also the correlations between meteorological characteristics. An attempt has been made to evaluate the role of influencing factors.

Reply to J. R. Wait by D. Rankin and R. P. Singh

Geophysics ◽  
1984 ◽  
Vol 49 (8) ◽  
pp. 1388-1388
Author(s):  
D. Rankin ◽  
R. P. Singh
Keyword(s):  
Magnetic Fields ◽  
Electric Fields ◽  
Horizontal Surface ◽  
Electric And Magnetic Fields ◽  
Surface Measurements

There is no real dispute between the magnetotellurist (Cagniard school) and the radio physicist (Norton school) in surface measurements of VLF and ULF fields. Each defines a mutually exclusive quantity which requires a different mode of measurement. The magnetotellurist measures the horizontal surface electric and magnetic fields, whereas, as Wait correctly points out, the radio physicist measures the horizontal and vertical electric fields.

Viscosity of a Polar Gas of Symmetric Top Molecules in Perpendicular Electric and Magnetic Fields

1978 ◽  
Vol 33 (2) ◽  
pp. 225-227 ◽  
Author(s):  
W. E. Köhler
Keyword(s):  
Magnetic Fields ◽  
Kinetic Theory ◽  
Electric Field ◽  
Electric Fields ◽  
Pressure Difference ◽  
Viscosity Coefficients ◽  
Electric And Magnetic Fields ◽  
Symmetric Top Molecules ◽  
Field Influence

A kinetic theory treatment of the influence of perpendicular magnetic and electric fields on the viscosity is given for a polar gas of symmetric top molecules. Expressions for the 9 independent viscosity coefficients are derived. In particular, the electric field influence on the transverse viscomagnetic pressure difference is studied.

Suppression of runaway of electrons in a Lorentz plasma. II. crossed electric and magnetic fields

1970 ◽  
Vol 4 (3) ◽  
pp. 441-450 ◽  
Author(s):  
Barbara Abraham-Shrauner
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Electric Field ◽  
Electric Fields ◽  
Cyclotron Frequency ◽  
Collision Frequency ◽  
Uniform Electric Field ◽  
Drift Motion ◽  
Electric And Magnetic Fields ◽  
The Magnetic Field

Suppression of runaway of electrons in a weak, uniform electric field in a fully ionized Lorentz plasma by crossed magnetic and electric fields is analysed. A uniform, constant magnetic field parallel to a constant or harmonically time varying electric field does not alter runaway from that in the absence of the magnetic field. For crossed, constant fields the passage to runaway or to free motion as described by constant drift motion and spiral motion about the magnetic field is lengthened in time for strong magnetic fields. The new ‘runaway’ time scale is roughly the ratio of the cyclotron frequency to the collision frequency squared for cyclotron frequencies much greater than the collision frequency. All ‘runaway’ time scales may be given approximately by t2E Teff where tE is the characteristic time of the electric field and Teff is the ffective collision time as estimated from the appropriate component of the electrical conductivity.

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