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This work proposes a complete and consistent set of cross sections for electron impact collisions with carbon monoxide (CO), to be published in the IST-Lisbon database with LXCat. The set is validated by comparing swarm parameters calculated using the two-term Boltzmann solver LoKI-B with available experimental data. A severe inconsistency between the total rotational and effective cross sections reported in the literature for low values of the electron energy (ϵ < 0.1 eV) is pointed out. It is shown that inelastic and superelastic collisions involving rotationally excited levels, as well as superelastic collisions with the first vibrational excited level, have to be taken into account to accurately calculate the electron energy distribution function. The relevance of these mechanisms implies a dependence of the effective momentum transfer cross section on the gas and vibrational temperatures and suggests its replacement by an elastic momentum transfer cross section. The electron kinetics in CO2–CO mixtures are also discussed in detail, namely the influence of vibrational excitation and of the CO2/CO ratio on the electron energy distribution function, rate coefficients and power transfer. The vibrational temperatures of both CO and the different vibrational modes of CO2 have a marked influence on the results, due to the importance of superelastic collisions with the vibrationally excited states of both gases. The presence of CO in the mixture modifies the energy transfer pathways and, at moderate reduced electric fields (∼30−100 Td), the vibrational excitation of CO can become the dominant energy loss mechanism, affecting the input of electron energy into the asymmetric stretching mode of CO2. [ABSTRACT FROM AUTHOR]

This paper studies two linear resonator sources, which use a continuous 2.45-GHz microwave excitation to produce stable microplasmas, in air and in argon, at atmospheric pressure. The discharges are produced and sustained within the 50-200-μm gap created between two metal electrodes with either 6 or 14 mm in length. Particular attention is given to the design and optimization of the sources (in terms of frequency tuning and power coupling), following a complementary approach based on simulations and experiments. Optical-emission-spectroscopy diagnostics allow one to deduce the rotational, vibrational, and excitation gas temperatures and the electron density (using Stark broadening measurements of the Hβ line-emission profile). [ABSTRACT FROM AUTHOR]

The study of the electromagnetic (em) field with a microwave-driven reactor excited by an axial injection torch (TIA) provides direct information about the power coupled to the device. A numerical simulation tool has been developed to calculate the 2-D em fields with a TIA-reactor system in the presence of plasma. The field images are used to monitor the variations of its distribution pattern with changes in the device dimensions, providing general guidelines for device optimization. [ABSTRACT FROM AUTHOR]