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The characteristics of a direct-current plasma torch discharging into air were investigated using a numerical model and laser-scattering temperature measurements. The results showed that cooling by air entrained by turbulent mixing caused a rapid deterioration in plume temperature in the direction away from the torch nozzle. There was good agreement between the model's predictions and experimental measurements.

The kinetics of the nucleation and growth of carbon nanotube and nanocane arrays on Ni catalyst nanoparticles on a silicon surface exposed to a low-temperature plasma are examined. The studies have shown that as the deposition time increases, nanostructure arrays have developed without widening the height distribution when the flux ionization degree is high, in contrast to the fairly broad nanostructure height distributions obtained when the degree of ionization is low.

This article examines Brussels' political and cultural geography. The author maintains Brussels is a culturally divided city in which the formal status of the city is based upon a single political-territorial unit within the larger Belgium.

We have assessed the production of ozone in a dielectric barrier discharge in which the discharge space is packed with glass spheres. We found that the presence of the glass spheres decreased the breakdown voltage, but that the ozone production rate was smaller at higher voltages than for a conventional air-gap ozonizer. The character of the discharge was found to range between a steady glow and short-lived filaments, depending on the sphere diameter, the width of the discharge gap, the voltage, the gas flow, and the discharge gas. We present images of the different discharge types. Index Terms--Air, dielectric barrier discharge, glass spheres, oxygen, ozone, ozonizer.

Free-burning arcs in argon-helium mixtures containing a large proportion of helium show a separation between the pink color characteristic of helium arcs and the violet color typical of argon arcs. Two effects are shown to contribute to this; first, demixing, which concentrates helium in the high-temperature region near the center of the arc, and second the fact that the radiative emission from helium, relative to that from argon, increases with temperature. Index Terms - Arc discharges, Argon, diffusion processes, helium, hydrodynamics, modeling, plasmas, spontaneous emission.