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The potential of decayed wood was investigated as a raw material to produce activated carbon. Both sound and decayed beech wood specimens were subjected to chemical activation with ZnCl2 at a carbonization temperature of 400 °C and 75% impregnation ratio to produce activated carbon. The produced activated carbon was tested using Brunauer--Emmett--Teller, Fourier transform infrared, scanning electron microscopy, and thermogravimetric analyses to investigate its properties. The activated carbon was used to adsorb rhodamine B dye in an aqueous solution. Additionally, to investigate the impact of activated carbon surface modification on the adsorption of rhodamine B dye, both kinds of activated carbon underwent surface modification using dielectricbarrier discharge (DBD) plasma at a high frequency of 20 kHz in the air atmosphere for 20 min at a voltage level of 10 kV. The modification of the activated carbon substantially improved its characteristics, resulting in a 20% increase in rhodamine B removal for the activated carbon derived from sound wood and a 12% increase for the activated carbon derived from decayed wood. The utilization of DBD air plasma in this method is suitable because of its simplicity, cost-effectiveness, and improved adsorption capacity in activated carbon. [ABSTRACT FROM AUTHOR]

While methane-powered vehicles produce fewer greenhouse gas emissions in comparison to conventional fuel vehicles, there is a significant amount of methane slip in their exhaust that needs to be treated. This study investigates non-thermal plasma (NTP) assisted catalytic methane oxidation as an alternative method for the low temperature methane slip abatement applicable to the exhaust of biogas methane-powered vehicles. It is concluded that high CH4 conversion and CO2 selectivity can be obtained using NTP-catalysis at low temperature with Pd/Al2O3 found to be the most promising candidate among all catalysts tested. In addition, it was found that CH4 conversion efficiency was dependent on the feed gas components and gas hourly space velocity as well as how the activation energy is introduced. For example, a combination of plasma and external heat supply provides advantages in terms of CH4 conversion along with lower plasma energy consumption. The presence of N2 and O2 in the feed gas during NTP-catalytic methane oxidation results in unfavourable NOX formation which linearly increases with CH4 conversion. These results conclude that the most suitable aftertreatment option involves the combination of an oxidation catalyst with plasma to target the hydrocarbon and CH4 oxidation, followed by an ammonia-SCR system to convert the NOX formed in plasma assisted zone. [ABSTRACT FROM AUTHOR]

The effect of non-thermal discharge plasma (DBD) on the inhibition of both gram-positive and gram-negative biofilms bacteria was examined at different plasma exposure times and gas flow. This effect induces damage to aqueous plasmid DNA. It reveals inactivation in bacterial biofilms for both types of bacteria with an increase in time of direct exposure to plasma and an increase in gas flow. The presence of positive bacteria outweighs the negative bacteria in susceptibility to inhibition. The result fractions of the DNA are indicate the whole DNA double-strand breaks and were determined using agarose gel electrophoresis. The damage level induced in the plasmid DNA is also enhanced with increased plasma irradiation time. [ABSTRACT FROM AUTHOR]

Copyright of La Revista Latinoamericana de Metalurgia y Materiales, RLMM is the property of Universidad Simon Bolivar, Departmento de Ciencia de los Materiales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of HOLOS is the property of Instituto Federal do Rio Grande do norte - IFRN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present work, the oxidation of isovaleraldehyde, a typical pollutant of indoor air, is investigated by using two different plasma DBD reactors: cylindrical and planar reactor. The study of the influence of the specific energy shows that its increment is accompanied by an increase of the removal efficiency. In fact, when specific energy extends three times, the removal efficiency is increased from 5 to 40 %. Moreover an increase of the specific energy induces a higher mineralization due to byproducts oxidation with reactive species production. The same behaviour is observed with ozone production. A generic mathematical model is developed to represent the experimental results obtained. This model is based on several mass transfer steps occurring in series between bulk and plasma phases. The degradation reaction mechanism is supposed to occur on two steps. Firstly, isovaleraldehyde leads to the formation of a fictitious equivalent intermediate (EI). In a second step, EI is transformed into CO and CO2. This approach gives a good agreement between modelling and experiments with a satisfactory overall description of byproducts formation. This original approach allows for the simulation of plasma oxidation kinetics process without knowing the complete chemical pathway. [ABSTRACT FROM AUTHOR]