Papers by Keyword: Discharge Plasma

Abstract: The treatment of industrial wastewaters collected from petrochemical works, gypsum plant, and printing and dyeing mill, was investigated at atmospheric pressure in air discharge plasma. The degradation effects of organic contaminants in water were compared for the printing and dyeing wastewater under different discharging conditions and for the wastewater from the other two plants under the same discharging conditions. The influences of several factors on chemical oxygen demand (COD) remove rate were studied experimentally. The results showed that the treatment effects for the same industrial wastewater differed significant under different discharge conditions. There may be a suitable discharge plasma treatment to specific industrial wastewater. Due to the removal rates of COD of industrial wastewaters with discharge plasma isn’t very high, therefore the discharge plasma water treating needs to combine conventional water treating methods or addition other catalyst to effectively remove organic pollutants in wastewater and obtain the expected treatment effect.

Abstract: The silicon substrates were hydrogenated at approximately room temperature and hydrogen concentration profiles vs. depth have been measured by SIMS. Czochralski grown (CZ) wafers, both n- and p-type conductivity, were used in the experiments under consideration. For analysis of hydrogen transport processes and quasichemical reactions the model of hydrogen atoms diffusion and quasichemical reactions is proposed and the set of equations is obtained. The developed model takes into account the formation of bound hydrogen in the near surface region, hydrogen transport as a result of diffusion of hydrogen molecules 2 H , diffusion of metastable complexes * 2 H and diffusion of nonequilibrium hydrogen atoms. Interaction of 2 H with oxygen atoms and formation of immobile complexes “oxygen atom - hydrogen molecule” (O - H2 ) is also taken into account to explain the hydrogen concentration profiles in the substrates of n-type conductivity. The computer simulation based on the proposed equations has shown a good agreement of the calculated hydrogen profiles with the experimental data and has allowed receiving a value of the hydrogen molecules diffusivity at room temperature.