Zum Skin-Effekt zeitlich periodischer elektromagnetischer Felder unter Berücksichtigung der magnetischen Widerstandsänderung

1966 ◽  
Vol 21 (9) ◽  
pp. 1436-1443
Author(s):  
Joachim Seebass
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Half Space ◽  
Skin Effect ◽  
Normal Skin ◽  
Constant Thickness ◽  
Conducting Layer ◽  
Successive Approximation Method ◽  
The Magnetic Field ◽  
Normal Skin Effect

Magnetoresistance leads to a change of the normal skin-effect. The electromagnetic field, periodic in time, is calculated by a successive approximation method for a half-space, the electric conductivity of which is dependent quadratically on the magnetic field. As expected results show the existence of uneven harmonics. Compared with the case without magnetoresistance, the a-c-resist-ance of some part of the half-space is altered by additional terms, which are dependent on the intensity of the current. Analogous results are given for a planar conducting layer of constant thickness.

Zum normalen Skin-Effekt unter Berücksichtigung der magnetischen Widerstandsänderung

1964 ◽  
Vol 19 (11) ◽  
pp. 1273-1276
Author(s):  
Rudolf Klein
Keyword(s):  
Magnetic Field ◽  
Field Dependence ◽  
Eddy Current ◽  
Magnetic Field Dependence ◽  
Skin Effect ◽  
Normal Skin ◽  
Maximum Value ◽  
High Fields ◽  
The Magnetic Field ◽  
Normal Skin Effect

The penetration of a magnetic field into an infinite metallic half-space is altered due to the presence of the magnetoresistance of the medium. MAXWELL’S equations modified by the magnetic field dependence of the conductivity are solved for the case where the field at the surface is switched on immediately and is constant afterwards. It is shown that due to magnetoresistance the field runs into the medium quicker compared to the case of the pure normal skin effect. The induced eddy current has its maximum value no longer at the surface of the specimen. The results are discussed in connection with pulse methods for the measurement of magnetoresistance in high fields.

Investigating flexible textile-based coils for wireless charging wearable electronics

2019 ◽  
Vol 50 (3) ◽  
pp. 333-345 ◽  
Author(s):  
Danmei Sun ◽  
Meixuan Chen ◽  
Symon Podilchak ◽  
Apostolos Georgiadis ◽  
Qassim S Abdullahi ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electrical Conductivity ◽  
Electromagnetic Field ◽  
Electric Field ◽  
Dimensional Stability ◽  
Screen Printing ◽  
Wearable Electronics ◽  
Wireless Charging ◽  
The Magnetic Field ◽  
Screen Printed

Smart and interactive textiles have been attracted great attention in recent years. This research explored three different techniques and processes in developing textile-based conductive coils that are able to embed in a garment layer. Coils made through embroidery and screen printing have good dimensional stability, although the resistance of screen printed coil is too high due to the low conductivity of the print ink. Laser cut coil provided the best electrical conductivity; however, the disadvantage of this method is that it is very difficult to keep the completed coil to the predetermined shape and dimension. The tested results show that an electromagnetic field has been generated between the textile-based conductive coil and an external coil that is directly powered by electricity. The magnetic field and electric field worked simultaneously to complete the wireless charging process.

Increasing the effective affect of the magnetic field on the weld pool

2021 ◽  
pp. 29-33
Author(s):  
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Magnetic Fields ◽  
Weld Pool ◽  
Electromagnetic Effects ◽  
Weld Pools ◽  
The Magnetic Field

Variants of weld pools obtained by verification with the influence of magnetic fields are considered. Methods for increasing the effectiveness of electromagnetic effects during welding are proposed. Keywords: welding, electromagnetic field, weld pool, induction, coating. [email protected], [email protected]

Normal skin effect in the polycrystals

1993 ◽  
Vol 3 (3) ◽  
pp. 177-198 ◽  
Author(s):  
I M Kaganova ◽  
M I Kaganov
Keyword(s):  
Skin Effect ◽  
Normal Skin ◽  
Normal Skin Effect

A Proof of the Biot-Savart Law

1968 ◽  
Vol 72 (689) ◽  
pp. 437
Author(s):  
B. G. Newman
Keyword(s):  
Magnetic Field ◽  
Field Theory ◽  
Electromagnetic Field ◽  
Fluid Mechanics ◽  
Small Length ◽  
Line Vortex ◽  
Line Current ◽  
Electromagnetic Field Theory ◽  
The Magnetic Field

The Biot-Savart law gives the velocity associated with an elemental portion of line vortex, or the magnetic field associated with an elemental portion of line current. The following proof may appeal to students who approach fluid mechanics or electromagnetic-field theory from the engineering viewpoint. It will be stated in terms of fluid mechanics. Consider a very small length δs of line vortex of circulation strength Γ. At P(x) the velocity δV associated with this portion depends on Γ δs and x.

Effects of Electromagnetic Fields on the Quantum Yield of Free Radicals in Cryptochrome

2019 ◽  
Vol 953 ◽  
pp. 127-132
Author(s):  
Yu Ling Chen ◽  
Du Yan Geng ◽  
Chuan Fang Chen
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Free Radicals ◽  
Free Radical ◽  
Quantum Yield ◽  
Electromagnetic Fields ◽  
Applied Magnetic Field ◽  
Geomagnetic Field ◽  
Quantum Biology ◽  
The Magnetic Field

In this paper, the effects of the quantum yield of free radicals in cryptochrome exposed to different electromagnetic fields were studied through the quantum biology. The results showed that the spikes characteristics was produced in the free radicals in cryptochrome, when it exposed to the applied magnetic field (ω = 50 Hz, B0 = 50 μT). The spikes produced by the electromagnetic field was independent of the changes of polar θ. When the frequency of the magnetic field increased, the spikes characteristics produced in unit time also increased. These results showed that the environmental electromagnetic field could affect the response of organisms to the geomagnetic field by influencing the quantum yield in the mechanism of free radical pair.It provided a basis for studying the influence of environmental electromagnetic field on biology, especially the navigation of biological magnetism.

A Proposed Experiment of Direct Detecting of the Vector Potential within Classical Electrodynamics

1997 ◽  
Vol 11 (12) ◽  
pp. 531-540
Author(s):  
V. Onoochin
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Charged Particle ◽  
Vector Potential ◽  
Energy Exchange ◽  
Short Pulse ◽  
Classical Electrodynamics ◽  
Direct Influence ◽  
Ultra Short Pulse ◽  
The Magnetic Field

An experiment within the framework of classical electrodynamics is proposed, to demonstrate Boyer's suggestion of a change in the velocity of a charged particle as it passes close to a solenoid. The moving charge is replaced by an ultra-short pulse (USP), whose characteristics should depend on the current in the coil. This dependence results from the exchange of energy between the electromagnetic field of the pulse and the magnetic field within the solenoid. This energy exchange could only be explained, by assuming that the vector potential of the solenoid has a direct influence on the pulse.

scholarly journals Effect of A Superstrate on On-Head Matched Antennas for Biomedical Applications

Electronics ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1099
Author(s):  
Md Rokunuzzaman Robel ◽  
Asif Ahmed ◽  
Akram Alomainy ◽  
Wayne S. T. Rowe
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Performance Improvement ◽  
Direct Contact ◽  
Biomedical Applications ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Conducting Layer ◽  
Electric And Magnetic Field ◽  
Biomedical Diagnosis

The effect of using a superstrate dielectric layer on an on-head matched antenna for biomedical diagnosis applications is investigated. Two on-head matched antennas are considered with different length meandered lines ensuring operation around 0.9 GHz frequency. The first antenna’s conductive radiating structure is in direct contact with the head phantom, whereas the second one utilises a 0.5 mm thick superstrate layer on top of the conducting layer as a buffer. The lateral dimensions of both antennas are held constant at 30 × 30 mm2. The electric and magnetic field distribution is analysed and the power penetration, 50 mm inside the head phantom, is derived from the electromagnetic field surrounding the antennas. Both homogeneous and inhomogeneous head phantoms are considered while evaluating the antennas in terms of their reflection coefficient, current distribution, electric field, magnetic field, specific absorption rate (SAR) and power penetration inside the head. The antennas are fabricated and measured utilizing an inhomogeneous phantom to validate the proposed performance improvement using a superstrate. It is shown that the superstrate antenna achieves a ~8 dB increase in power penetration inside the head phantom along with a 0.0731 W/kg decrease in SAR compared to the antenna without a superstrate.

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