Impulse formulations of Hall magnetohydrodynamic (MHD) equations are developed. The Lagrange invariance of a generalized magnetic helicity is established for Hall MHD. The physical implications of this Lagrange invariant are discussed. The discussion is then extended to compressible Hall MHD. Compressibility effects are show not to affect, as to be expected, the physical implications of the gen...

background & aim: the use of herbal extracts as safe and effective factors for eradicating of stores pests has attracted much attention. in this paper, the bio-effects of fumigation and repellent effects of essential oil of eucalyptus globolus were investigated on red flour beetle. experimental: in this study, the toxicity, fumigation and repellency contacts were assayed by topical applicat...

in this research, the surface stress effect on the nonlocal vibration of piezoelectric square plate reinforced by single walled carbon nanotubes (swcnts) based on classical plate theory (cpt) and first order shear deformation theory (fsdt) is presented. the elastic properties of piezoelectric nanocomposite plate are estimated by eshelby-mori-tanaka and the extended mixture rule approaches. the ...

The quasiclassical Green function formalism is used to describe charge and spin dynamics in the presence of spin-orbit coupling. We review the results obtained for the spin Hall effect on restricted geometries. The role of boundaries is discussed in the framework of spin diffusion equations.