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This paper presents a model of the typical dielectric barrier plasma discharge at atmospheric pressure, structured as an equivalent electric circuit whose elements are identified with, and deducted from, the main influential variables of the process, namely, the applied gas, the geometry of the reactor, the breakdown parameters, as well as the power supply associated to the dielectric barrier discharge cell. Considering a parallel-plate reactor and a high-voltage sinusoidal power supply, an electrical comprehensive Simulink/MATLAB model has been developed in order to reveal the interaction between these two elements. The main components of this discharge model are as follows: 1) a double dielectric capacitance; 2) a voltage-controlled current source; and 3) a gas capacitance associated to the ionized gas. A sinusoidal voltage of up to 15 kV peak to peak at frequencies of 12.5 and 47 kHz has been applied to the discharge electrodes. The electrical model is based on the power law proposed by Roth, which defines the V-I behavior during the discharge startup. A series of simulations has been carried out in order to estimate the total current and voltage consumed during each discharge and to identify those parameters which are not measurable during the process. Finally, both the experimental and simulated voltage and current results in helium, argon, and nitrogen, as well as their Q-V graphics, are shown, and a comparison between them is discussed. Index Terms--Dielectric barrier discharge (DBD), voltage-controlled current source, voltage source inverter (VSI).

In this paper, we present a model (which is structured as an equivalent electric circuit whose elements are identified and deducted from the nature of the medium, the ionization and expansion process of the streamers that convey the pre-breakdown current, and the energy associated to the electric breakdown in water) and a simulation of a pulsed corona discharge (PCD). Considering this, a coaxial reactor and an inexpensive and compact high-voltage pulsed-power supply (PPS) system were designed and constructed with the purpose of carrying out the PCD experimentally. The simulation results enable the prediction of the behavior of the discharge. The coaxial reactor is constituted by a cylindrical chamber and a straight central rod. The PPS operates within the 100-2000-Hz repetition rate and 0-30-kV amplitude ranges. All the system has been tested, and the first electrical results, voltage, and current waveforms, are presented. Index Terms--Electric breakdown, plasma applications, plasma generation, power system simulation.

Background and Aims: The efficacy of a direct application of plasma needle to in vivo wound healing was experimentally studied in mice. This kind of plasma has achieved considerable success in blood coagulation and tissue restoration in mice. In the development of the present study, an argon plasma needle was chosen for coagulation purposes, whereas for healing purposes, a helium plasma needle was used., Methods: Treatment was applied with a plasma needle produced by argon and helium to a wound induced in laboratory mice. Tissue regeneration was carried out by three argon plasma treatments with 0.5 SLPM flow for 1 min and three treatments of helium with 1.5 SLPM flow. Intervals between each treatment were 5 min and 60 min for argon and helium plasmas, respectively, thus completing a total treatment time of 180 min. Histological sections were performed to corroborate the internal bleeding and tissue regeneration., Results: After three treatments with argon plasma, the blood produced in the wound was coagulated and protein material appeared. By means of treatment with helium plasma, an approach of the wound edges was produced until the conclusion thereof. These results were corroborated histologically., Conclusions: This type of acceleration during the skin wound healing process can be attributed to the formation of reactive species such as NO, which were increased in the helium plasma needle with respect to the argon plasma needle., (Copyright © 2013 IMSS. Published by Elsevier Inc. All rights reserved.)