The measurement of magnetic susceptibilities with commercially available milli — Oerstedmeters,II

In the preceeding paper on this subject a method was described which enabled the measurement of magnetic susceptibilities in constant magnetic fields. In the present paper it is demonstrated that the application of an alternating magnetic field instead of a constant field is advantageous. Many environmental disturbances are eliminated, the measurement time is highly reduced and the amplitude of the magnetizing field can be brought back to 60 Oersted at which fields the sensitivity is still a few percent for diamagnetic substances.     

On force-free magnetic fields and beltrami flows

I.Intr0ductionLhstandSchldterlllhavepointedoutthatcosmicmagneticfieldsmightoftensatisfytheconditionwhereHdenotestheintensityofthemagneticfieId,andathescalarfunctionofpositionUnderthisconditionthecurrentflowseverywhereparalleltothemagneticfieId'andthvanish…     

Atomic beam magnetometer

The application of a novel atomic beam magnetic resonance technique to the measurement of magnetic fields is described. The technique has been used previously in electric field experiments to determine the upper limit to the permanent electric dipole moment of the cesium atom. Two different electric field modulation schemes were used which demonstrate the sensitivity of the technique. In one scheme (sinusoidal modulation) the sensitivity to magnetic field changes is inferred; in the second scheme (squarewave modulation) small magnetic field changes were measured directly.     

Atomic beam magnetometer

The application of a novel atomic beam magnetic resonance technique to the measurement of magnetic fields is described. The technique has been used previously in electric field experiments to determine the upper limit to the permanent electric dipole moment of the cesium atom. Two different electric field modulation schemes were used which demonstrate the sensitivity of the technique. In one scheme (sinusoidal modulation) the sensitivity to magnetic field changes is inferred; in the second scheme (squarewave modulation) small magnetic field changes were measured directly.     

Diffusion of superintense pulsed magnetic fields

The phenomena accompanying the diffusion of superintense pulsed magnetic fields in metals are studied. Solutions are obtained for the diffusion of a constant superintense magnetic field into a half-space with a plane boundary and for the diffusion of an axial concentrated magnetic field. The limiting magnetic fields which can be obtained in various experimental devices are found. The results are compared with experiment.     

Unsteady hydromagnetic Couette flow of dusty fluid with temperature dependent viscosity and thermal conductivity

In the present paper the unsteady Couette flow and heat transfer of a dusty conducting fluid between two parallel plates with temperature dependent viscosity and thermal conductivity are studied. A constant pressure gradient and an external uniform magnetic field are applied. The governing coupled momentum and energy equations are solved numerically using finite differences. The effect of the variable viscosity and thermal conductivity of the fluid and the uniform magnetic field on the velocity and temperature fields for both the fluid and dust particles is discussed.     

Stabilization of an alternating-current-carrying plasma filament by a quadrupole magnetic field

Dynamic stabilization of straight and toroidal current-carrying plasma jets by a high-frequency quadrupole magnetic field was proposed by Osovets [1]. A more rigorous theoretical analysis of the problem was performed by Levin and Rabinovich [2], who obtained a Routh function for studying the dynamics of the filament in various magnetic fields for a thin filament experiencing longwave serpentine- and construction-type disturbances. In this paper, the method proposed in [2] is applied to the stabilization of a plasma filament in which (as distinct from [1,2]) flows an alternating current while the quadrupole field is either constant, or varies at a high frequency, as in [1,2].The author is indebted to M. L. Levin for useful discussions and advice.     

A qualitative investigation of the equations of quasi-one-dimensional magnetohydrodynamic channel flow

A qualitative investigation of the system of differential equations describing the quasi-one-dimensional flow of an electrically conducting medium at small magnetic Reynolds numbers gives an idea of the different possible flow patterns occuring when the electromagnetic field and channel shape are given in different ways. Such a treatment is essential for the calculation of one-dimensional flows, and also for the solution of variational problems [1].In the literature devoted to this question studies have been made of flow in a one-dimensional electromagnetic field and a channel of constant cross section [2], as well as of the flow when the magnetic field is described by specially given functions of the flow velocity [3]. These cases reduce to the analysis of integral curves in a plane.In the present paper the investigation is carried out for an arbitrary distribution of the electric and magnetic fields and channel shape, which leads to a consideration of the behavior of integral curves in three-dimensional space. The qualitative results are illustrated by examples.     

Effect of induced magnetic field on natural convection in vertical concentric annuli

In the present paper,we have considered the steady fully developed laminar natural convective flow in open ended vertical concentric annuli in the presence of a radial magnetic field.The induced magnetic field produced by the motion of an electrically conducting fluid is taken into account.The transport equations concerned with the considered model are first recast in the non-dimensional form and then unified analytical solutions for the velocity,induced magnetic field and temperature field are obtained for the cases of isothermal and constant heat flux on the inner cylinder of concentric annuli.The effects of the various physical parameters appearing into the model are demonstrated through graphs and tables.It is found that the magnitude of maximum value of the fluid velocity as well as induced magnetic field is greater in the case of isothermal condition compared with the constant heat flux case when the gap between the cylinders is less or equal to 1.70 times the radius of inner cylinder,while reverse trend occurs when the gap between the cylinders is greater than 1.71 times the radius of inner cylinder.These fields are almost the same when the gap between the cylinders is equal to 1.71 times the radius of inner cylinder for both the cases.It is also found that as the Hartmann number increases,there is a flattening tendency for both the velocity and the induced magnetic field.The influence of the induced magnetic field is to increase the velocity profiles.     

Magnetoelastic bending and stability of soft ferromagnetic rectangular plates

I.IntroductionSofar,twokindsofphenomenaofmagnetoelasticinteractiontoferromagneticplatesinappliedmagneticfieldshavebeenfound.Oneisthemagnetoelasticbuchlingorillstabllitytoacantileveredbeam-plateinatransversemagneticfieldt'],thatisthephen1Onlenollot'negiltivemagneticstiffness,whiletheotheristheincreaseofnaturalfrequencyoftheplatewhichisfreelyviratinginanin-planemagneticfieldl=],thatisthephenomenonofpositivemagneticstiffness.Inordertosimulatethesetwokindsofexperimentalphenomena,sometheoreticalmo…