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In this paper, a dielectric-barrier discharge (DBD) of Ar:\N2 mixtures at atmospheric pressure is studied in relation to plasma jet production. The discharge takes place in a capillary dielectric tube, and it is sustained by positive high-voltage pulses. It is herein claimed that, apart from the traditional DBD (which is developed perpendicularly to the gas flow and can produce afterglows), plasma jet propagates simultaneously parallel to the gas flow due to ionization waves guided by the dielectric tube. A quite simple electrical model is applied to simulate the proposed DBD and plasma jet coexistence. The concept of capacitive behavior of both barrier discharge and jet is taken into account. This model in combination with UV–visible optical emission spectroscopy and conventional photography supports the aforementioned statements. The dependence of the jet domination against the afterglow on the gas mixture is demonstrated, and the \N2 additive at 2.5 \%–3\% in Ar is found to be the most efficient for jet production. The model runs with the measured interelectrode voltage as input and yields the circuit total current as output. Matching between the measured current and the model output is attempted by adjusting two free parameters. This tuning of the free parameters provides reliable values for the electrical components of the model. Thus, a simple mean for realistic representation of both DBD and jet is achieved. This tool could be applied to the design of plasma jet reactors. [ABSTRACT FROM PUBLISHER]

Hereby, five dipolar electron cyclotron resonance elementary sources are assembled to form a 2D network for H− negative ion production. The resultant magnetic field of the network is considered by means of numerical and experimental data, and an artistic photo of the produced plasma is presented. Laser photodetachment measurements in these plasmas confirm the applicability of such networks to this specific purpose. [ABSTRACT FROM PUBLISHER]

The outlet of a plasma microjet system operating with noble gases at atmospheric pressure is connected to dielectric guides, and the transfer of excited species to long downstream regions is demonstrated by means of photography. Both straight and curved particle propagation paths are achieved and illustrated by imaginative images. The latter justify the potential use of this atmospheric-pressure plasma device to biomedical applications. [ABSTRACT FROM AUTHOR]

Argon plasma jet is generated at atmospheric pressure under monopolar pulsed conditions. Images demonstrating luminous activity due to excited gaseous species are presented in combination with voltage-current waveforms in nanosecond scale. The jet is physically altered (length, diameter, and luminosity) as a function of two electrical parameters, i.e., the amplitude and frequency of the high voltage applied. Temperature measurements indicate the potential use of this system to diverse surface treatments, laying from biomedical applications at room temperature to inert material modification where thermal effect is a prerequisite. [ABSTRACT FROM AUTHOR]