A linear stability analysis of the low-current gliding arc discharge in the transitional regime is performed. It is shown that the gliding arc remains stable during the evolution and gradually transforms into a more nonequilibrium one. The low-current arc discharge can propagate with the effect of “overshooting” at which the gliding arc extinguishes long after its maximum power has been achieved. Analytical and numerical solutions explain the general behavior of the low-current gliding arc and are in a good agreement with our experiment.

Vertically aligned multi-wall carbon nanotube (VA-MWCNT) arrays have been used for deposition of molybdenum sulphide from a water solution of ammonia molybdate and thiourea. A hydrothermal synthesis at 175 8C resulted in formation of quasi-spherical nanoparticles inside and on the top surface of arrays without destruction of the array structure. X-ray photoelectron spectroscopy revealed a molybdenum disulfide (MoS 2 ) composition of the nanoparticles, while Raman spectroscopy detected the bands characteristic of light scattering in the MoS 2 crystallites only after a treatment of synthesis products in hydrogen flow. As compared to the initial VA-MWCNTs, the composites showed enhanced specific capacitances in 1M H 2 SO 4 electrolyte especially at low scan rates due to redox reactions involving MoS 2 . The reactions were more pronounced for the hydrogen treated composite.Cyclic voltammetry curves demonstrate an enhanced specific capacitance of MoS 2 /MWCNT array (fragment of the structure is shown in the insert) as compared to initial array due to redox reactions.

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