As a first step to a better understanding of the voltage-current characteristics of fine filament multifi lamentary composite superconductors, the electric field and critical current along a single spiral-shaped fi lament were studied. When the spiral superconducting filament was carrying constant current and placed in a magnetic field, the local critical current and electric field vary due to ...

Swing-excited dynamo-induced magnetic fields in spiral galaxies are studied. We investigate the phenomenon of swing excitation with linear and nonlinear 3D numerical simulations of the galactic dynamo. The model includes differential rotation, axisymmetric and isotropic α-effect and uniform eddy diffusivity. The nonaxisymmetry is introduced via large-scale radial and azimuthal velocity componen...

We present three-frequency VLA observations of the flocculent spiral galaxy NGC 4414 made in order to study the magnetic field structure in absence of strong density wave flows. NGC 4414 shows a regular spiral pattern of observed polarization B-vectors with a radial component comparable in strength to the azimuthal one. The average pitch angle of the magnetic field is about 20 • , similar to ga...

According to the classical axisymmetric dynamo concept, differentially rotating galaxies which lack organized optical spiral patterns and density wave flows should still have spiral magnetic fields with a substantial radial component. To check this hypothesis we observed two flocculent spirals, NGC 3521 and NGC 5055, in the radio continuum (total power and polarization) at 10.55 GHz with a reso...

Materials that combine coupled electric and magnetic dipole order are termed 'magnetoelectric multiferroics'. In the past few years, a new class of such materials, 'induced-multiferroics', has been discovered, wherein non-collinear spiral magnetic order breaks inversion symmetry, thus inducing ferroelectricity. Spiral magnetic order often arises from the existence of competing magnetic interact...

The evolution of large-scale magnetic fields in disk galaxies is investigated numerically. The gasdynamical simulations in a disk perturbed by spiral or bar potential are incorporated into the kinematic calculations of induction equations to elucidate the effects of nonaxisymmetric disk structure on magnetic fields. The effects of interstellar turbulence are given as the turbulent diffusion of ...

Observational evidence for dynamo action in spiral galaxies is reviewed, and the capabilities of various theories in explaining the basic features of galactic magnetic fields are discussed. Mean-field dynamo models appear to be unique in providing a coherent explanation of a wide variety of magnetic features in spiral galaxies. Reliable modelling of global magnetic structures, such as the magne...

In the past years, magnetism-driven ferroelectricity and gigantic magnetoelectric effects have been reported for a number of frustrated magnets featuring ordered spiral magnetic phases. Such materials are of high-current interest due to their potential for spintronics and low-power magnetoelectric devices. However, their low-magnetic ordering temperatures (typically <100 K) greatly restrict the...

Microparticle separation and concentration based on size has become indispensable in many biomedical and environmental applications. In this paper we describe a passive microfluidic device with spiral microchannel geometry for complete separation of particles. The design takes advantage of the inertial lift and viscous drag forces acting on particles of various sizes to achieve differential mig...