scholarly journals An Analogy Between the Effects of Fluctuating Electric Fields and Steady Magnetic Fields in Isotropic Conductors when a Universal Relaxation Time Cannot Be Defined

1960 ◽  
Vol 13 (1) ◽  
pp. 95
Author(s):  
EJ Moore
Keyword(s):  
Magnetic Field ◽  
Relaxation Time ◽  
Electric Field ◽  
Electric Fields ◽  
High Frequency ◽  
Present Note ◽  
Isotropic Solid ◽  
High Frequency Electric Field ◽  
Circular Frequency ◽  
Steady Magnetic Field

It is well known that when a " universal" time of relaxation ("t') exists, the influence of a harmonically varying electric field (F cceiOlt) on the transport properties of a solid may be taken into account by replacing "t' by "t'/(l +iCil"t'). Dingle (1956a) demonstrated that, for an isotropic solid, the effect of a steady magnetic field may similarly be obtained by replacing "t' by "t'/(l+j~l"t') with an applied d;c. electric field, and by "t'/[l+(iCil+jO)"t'] with an a.c. field. (Here j2= -1, ij -=1= -1, and 0=( -e)H/mc is the circular frequency of precession of an electron.) The object of the present note is to show that this analogy between a high frequency electric field and a steady magnetic field still exists, even when a " universal" relaxation time cannot be defined.

Some Applications of High-Frequency Electric Currents to the Latex Industry

1938 ◽  
Vol 11 (3) ◽  
pp. 570-574
Author(s):  
Henri Leduc
Keyword(s):  
Dielectric Loss ◽  
Electric Field ◽  
Electric Fields ◽  
High Frequency ◽  
Specific Effect ◽  
Entire Body ◽  
Rubber Latex ◽  
Joule Effect ◽  
High Frequency Electric Field ◽  
Rubber Particles

Abstract The “radiocoagulation” of latex has been developed in the laboratories of L'Office National des Recherches et Inventions by Dufour and Leduc, who conceived the idea of applying the effect of electric fields of high frequency to rubber latex. When latex is exposed to the action of an electric field of high frequency, the entire body of liquid is heated uniformly, provided that the electric field itself is uniform. The causes of this heating effect are difficult to ascertain because various phenomena are involved simultaneously, e. g., a dielectric loss in the rubber and a loss by the Joule effect in the serum. Each of these effects is, according to conditions, the predominant one, e. g., by increasing the conductivity of the serum, electrolytes such as sodium sulfate or ammonium sulfate increase the Joule loss, U2/R, whereas an increase in the concentration of latex tends to increase the dielectric loss. Finally, since rubber particles are not electrically neutral, they are subject to alternating forces of the electric field, which is a specific effect of the high frequency, and these forces impart to the rubber particles movements throughout the liquid. Now latex can be rendered sensitive to mechanical forces, i. e., some mixtures can be coagulated by slight agitation. Accordingly it is conceivable that a high-frequency electric field, by setting the rubber particles in motion throughout the emulsion, is capable of coagulating a mass of latex exposed to the field.

scholarly journals RESEARCH OF INFLUENCE OF HIGH-FREQUENCY ELECTRICAL FIELD ON SOWING QUALITY OF CEREAL SEEDS

2019 ◽  
pp. 95-99
Author(s):  
Ivan Solovey
Keyword(s):  
Electric Field ◽  
Winter Wheat ◽  
Electric Fields ◽  
High Voltage ◽  
High Frequency ◽  
Experimental Studies ◽  
Voltage Source ◽  
Seed Systems ◽  
High Frequency Electric Field ◽  
Frequency Electric Field

A study on the effect of high-frequency electric field on cereal seeds to increase seed germination and plant growth is presented. The study was conducted in the treatment of winter wheat seeds. High-voltage electric fields are one of the promising means of influencing crop seeds. One of the areas of use of high frequency high voltage electric fields is pre-sowing seed treatment, storage and processing. Experimental studies were conducted in the laboratory on a specially designed installation using a high-frequency high-voltage source. Processing doses have been established which make it practical to use a high-frequency, high-voltage electric field in electrotechnical winter wheat seed systems. Positive influence of high-frequency electric field on increase of sowing qualities and yielding properties of seeds is established. The optimal mode for determining the winter wheat field is the micro field, the mode is 16.8 kJ per 1 kg energy, the hour is 4 seconds, and the laboratory laboratory is 20% similar.

Mass Transport and DC Electromotive Force Induced in Ionic Crystals by High-Frequency Electric Field

1994 ◽  
Vol 369 ◽  
Author(s):  
K. I. Rybakov ◽  
V. E. Semenov
Keyword(s):  
Electric Field ◽  
Mass Transport ◽  
Electric Fields ◽  
High Frequency ◽  
Theoretical Study ◽  
Moderate Intensity ◽  
Ionic Crystals ◽  
Crystalline Materials ◽  
High Frequency Electric Field ◽  
Electromagnetic Pressure

AbstractResults of the theoretical study of the effects produced on ionic crystals by highfrequency electric fields of moderate intensity are presented. The ponderomotive action of the electric field on the space charge induced by it in a thin layer within the crystal near its surface causes directional mass transport that leads to plastic deformation and induces a stationary distribution of electric potential. The analysis shows that the proposed effect (that appears to be equivalent to the action of mechanical stresses which exceed the electromagnetic pressure by many orders of magnitude) can influence the results of processing of ionic crystalline materials significantly.

scholarly journals Comparative analysis the performance of electrochemical water softening between high frequency electric fields and direct current electric fields based on orthogonal experimental methods

2021 ◽  
Vol 83 (7) ◽  
pp. 1677-1690
Author(s):  
Wei Lin ◽  
Zhonghao Wang ◽  
Wei Wang ◽  
Qi Chen ◽  
Jianmin Xu ◽  
...  
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Direct Current ◽  
High Frequency ◽  
Feed Concentration ◽  
Water Softening ◽  
Direct Current Electric Field ◽  
High Frequency Electric Field ◽  
Hardness Removal ◽  
Current Electric Field

Abstract Electrochemical water softening has been widely used in industrial circulating cooling water systems; however, their low deposition efficiency is the main drawback that limits usage in medium to large enterprises. In this work, the effect of different parameters on the hardness removal efficiency and energy consumption of the electrochemical water softening system is experimentally studied, and the performance of water softening applied by high frequency electric fields and direct current electric fields are comparative analyzed. The impact factors of the electrochemical water softening system are as follows: initial feed concentration of solute, magnitude of voltage, inter-electrode distance, area of cathode and frequency of power supply. To improve the analysis efficiency, the L25 (55) orthogonal table is used to investigate the five different factors at five levels. The experimental results are shown that the initial feed concentration of solute is the most significant factor affecting the hardness removal efficiency. The optimal combination for water softening in the group applied by high frequency electric field and direct current electric field are A3B2C1D4E3 and A2B5C3D1 respectively. The energy utilization of the device applied by high frequency electric field is 3.2 times that applied by direct current electric field. The practice shows that direct current electric fields have a better softening effect, and are is more suitable for scaling ion removal. Particle image velocimetry (PIV) was used to observe the flow field induced by the electrolysis and found that the vertical and horizontal velocities of the flow field at low voltage are conducive to the migration of scaled ions to the cathode, and then the electrolytic reaction and deposition reaction synergy effect is the optimal.

scholarly journals Double layers in the downward current region of the aurora

2003 ◽  
Vol 10 (1/2) ◽  
pp. 45-52 ◽  
Author(s):  
R. E. Ergun ◽  
L. Andersson ◽  
C. W. Carlson ◽  
D. L. Newman ◽  
M. V. Goldman
Keyword(s):  
Magnetic Field ◽  
Electron Beam ◽  
Phase Space ◽  
Electric Field ◽  
Electric Fields ◽  
Double Layers ◽  
Parallel Electric Field ◽  
Electrostatic Waves ◽  
Current Region ◽  
Decisive Evidence

Abstract. Direct observations of magnetic-field-aligned (parallel) electric fields in the downward current region of the aurora provide decisive evidence of naturally occurring double layers. We report measurements of parallel electric fields, electron fluxes and ion fluxes related to double layers that are responsible for particle acceleration. The observations suggest that parallel electric fields organize into a structure of three distinct, narrowly-confined regions along the magnetic field (B). In the "ramp" region, the measured parallel electric field forms a nearly-monotonic potential ramp that is localized to ~ 10 Debye lengths along B. The ramp is moving parallel to B at the ion acoustic speed (vs) and in the same direction as the accelerated electrons. On the high-potential side of the ramp, in the "beam" region, an unstable electron beam is seen for roughly another 10 Debye lengths along B. The electron beam is rapidly stabilized by intense electrostatic waves and nonlinear structures interpreted as electron phase-space holes. The "wave" region is physically separated from the ramp by the beam region. Numerical simulations reproduce a similar ramp structure, beam region, electrostatic turbulence region and plasma characteristics as seen in the observations. These results suggest that large double layers can account for the parallel electric field in the downward current region and that intense electrostatic turbulence rapidly stabilizes the accelerated electron distributions. These results also demonstrate that parallel electric fields are directly associated with the generation of large-amplitude electron phase-space holes and plasma waves.

scholarly journals Mapping of steady-state electric fields and convective drifts in geomagnetic fields – Part 1: Elementary models

2016 ◽  
Vol 34 (1) ◽  
pp. 55-65 ◽  
Author(s):  
A. D. M. Walker ◽  
G. J. Sofko
Keyword(s):  
Magnetic Field ◽  
Steady State ◽  
Electric Field ◽  
Electric Fields ◽  
Magnetic Field Line ◽  
Geomagnetic Field ◽  
Geomagnetic Field Models ◽  
Spatial Derivatives ◽  
Field Lines ◽  
The Magnetic Field

Abstract. When studying magnetospheric convection, it is often necessary to map the steady-state electric field, measured at some point on a magnetic field line, to a magnetically conjugate point in the other hemisphere, or the equatorial plane, or at the position of a satellite. Such mapping is relatively easy in a dipole field although the appropriate formulae are not easily accessible. They are derived and reviewed here with some examples. It is not possible to derive such formulae in more realistic geomagnetic field models. A new method is described in this paper for accurate mapping of electric fields along field lines, which can be used for any field model in which the magnetic field and its spatial derivatives can be computed. From the spatial derivatives of the magnetic field three first order differential equations are derived for the components of the normalized element of separation of two closely spaced field lines. These can be integrated along with the magnetic field tracing equations and Faraday's law used to obtain the electric field as a function of distance measured along the magnetic field line. The method is tested in a simple model consisting of a dipole field plus a magnetotail model. The method is shown to be accurate, convenient, and suitable for use with more realistic geomagnetic field models.

Sign in / Sign up

Export Citation Format

Share Document