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The morphology, microstructure and magnetic properties of the magnetic cobalt nanoparticles are analyzed by electron microscopy, micro-Raman spectroscopy and superconducting quantum interference device magnetometry. The results have shown that the cobalt nanoparticles prepared are noncrystalline but coated with the graphitic carbon layers.

First-principles calculations are employed to study the stable configuration, electronic structures, and magnetic behaviors for S adsorption on graphene. The results provide insight into the coverage dependent absorption site of S on graphene and the surface potential energy curve which confirmed graphene as suitable candidate for the S storage.

A theoretical study of the equilibrium spin current (ESC) flowing in a ferromagnet/ferromagnet (FM/FM) graphene junction with noncollinear magnetizations, in which FM insulator is deposited to induce the FM correlation in graphene is presented. The ESC in FM/FM graphene junctions exhibited electron-hole inversion symmetry while in normal FM/FM junctions it showed electron-hole inversion antisymmetry.

The resonant tunneling in nonuniform magnetically modulated graphene-based double-barrier structures is examined, which is realized by depositing successive ferromagnetic stripes on graphene monolayer. The results have shown that the shot noise is a sensitive probe for disclosing mechanism of electronic transport in graphene.

The structural properties of nitrogenated amorphous carbon deposited by radiofrequency magnetron sputtering of graphite in pure [N.sub.2] plasma are examined as a function of the substrate temperature and radiofrequency discharge power. The studies have shown that the structural changes are well correlated with modifications of the optical and transport properties.

The results from quantitative analysis on orbital magnetization of graphene under a magnetic field are presented. The magnetic susceptibility of the graphene nanoribbons was found to be very sensitive to the ribbon width and chirality and the zero-field susceptibility increased with the ribbon width.

Peierl coupling tight-binding model is used for studying the low energy magnetoelectronic properties of zigzag graphene ribbons by changing the ribbon width from the nanometer to the mesoscopic scale. The transition channels of the Landau peaks are identified and it is shown that the bearded defects have not affected the magnetoabsorption peaks due to the Landau levels.

The preparation and crystal structure characterization of graphite doped Mg[B.sub.2-x][C.sub.x] (x = 0.0, 0.1, 0.2, and 0.3) samples are reported. The results suggest that flux pinning strength could be enhanced at higher magnetic fields in optimally graphite doped sample.