A magnetic field generator with active compensation of external fields

In this paper we studied the weakly nonlinear stage of stationary convective instability in a nonuniformly rotating layer of an electrically conductive fluid in an axial uniform magnetic field under the influence of: a) temperature modulation of the layer boundaries; b) gravitational modulation; c) modulation of the magnetic field; d) modulation of the angular velocity of rotation. As a result of applying the method of perturbation theory for the small parameter of supercriticality of the stationary Rayleigh number nonlinear non-autonomous Ginzburg-Landau equations for the above types of modulation were obtaned. By utilizing the solution of the Ginzburg-Landau equation, we determined the dynamics of unsteady heat transfer for various types of modulation of external fields and for different profiles of the angular velocity of the rotation of electrically conductive fluid.

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Study of Pulsed Magnetic Field Generator for Magnetoacoustic Tomography Technology with Magnetic Induction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.805 ◽

2011 ◽

Vol 383-390 ◽

pp. 805-810

Author(s):

Yan Hong Li ◽

Guo Qiang Liu ◽

Shi Qiang Li ◽

Hui Xia

Keyword(s):

Magnetic Field ◽

Magnetic Induction ◽

Operation Mode ◽

Pulsed Magnetic Field ◽

Good Prospect ◽

Inductive Load ◽

Impedance Tomography ◽

Charging System ◽

Narrow Width ◽

Magnetic Field Generator

On the basis of contrasting the research of home and abroad, this paper studies array magnetoacoustic tomography with magnetic induction as well logging new method. The paper introduces the design of the pulsed magnetic field for magnetoacoustic tomography with magnetic induction, analyses operational principle and parameters of charging system, introduces the operation mode of the discharging system in detail, the constitution of key parts circular plate coil, and realizes narrow width, high peak and repeat pulsed current with inductive load finally, and we obtained the distribution of the magnetic field. Magnetoacoustic tomography with magnetic induction combines the technology of Electrical Impedance Tomography and ultrasonic imaging, it can provide an impedance image with good accuracy and high spatial resolution, the method has a good prospect of application and extension in detection of resource, medical imaging and other fields.

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ON THE MAGNETIC PEKAR FUNCTIONAL AND THE EXISTENCE OF BIPOLARONS

Reviews in Mathematical Physics ◽

10.1142/s0129055x12500146 ◽

2012 ◽

Vol 24 (06) ◽

pp. 1250014 ◽

Cited By ~ 5

Author(s):

M. GRIESEMER ◽

F. HANTSCH ◽

D. WELLIG

Keyword(s):

Magnetic Field ◽

Constant Magnetic Field ◽

Local Fields ◽

External Fields

First, this paper proves the existence of a minimizer for the Pekar functional including a constant magnetic field and possibly some additional local fields that are energy reducing. Second, the existence of the aforementioned minimizer is used to establish the binding of polarons in the model of Pekar–Tomasevich including external fields.

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