Tomasz Giżewski

Power Systems of Plasma Reactors for Non-Thermal Plasma Generation

Abstract Recently, many different plasma sources are being investigated for exhaust gases treatment, odor abatement, VOC removal, soil conditioning, surface decontamination or tissue disinfection and sterilization. Among many different plasma reactors investigated in laboratories, gliding arc discharges (GAD), dielectric barrier discharges (DBD), pulsed discharges (PD), atmospheric pressure glow discharges (APGD) and atmospheric pressure plasma jets (APPJ) seem to be the most promising for high pressure low temperature applications. They can be designed as multi-electrodes’ high power system that can be used in environment protection processes, like decontamination of large surfaces and treatment of large volume of polluted gases, as well as small size and low power devices for biomedical applications, like plasma healing, disinfection and sterilization. Paper presents review of power supply systems for cold plasma reactors. Dielectric Barrier Discharge (DBD), Gliding Arc Discharge (GAD) and atmospheric pressure plasma jet (APPJ) reactors with their supply systems have been discussed from the point view of their characteristics, possibility to control power to the discharge and efficiency. Taking into account the plasma reactor characteristics and nature (nonlinear resistive and/or capacitive) different solutions of power suppliers have been presented: transformer type, AC/DC/AC inverter, RF-frequency system and frequency resonant inverter.

Electronic and magneto-transport in chirality sorted carbon nanotube films

This research details electronic and magneto-transport in unsorted and chirality-enriched carbon nanotube (CNT) films. By measuring the electrical conductivity from 4 K to 297 K, we were able to assign the governing mechanism of electronic transport. Fluctuation-induced tunnelling was in accordance with the obtained data and very well matched the underlying physics. We demonstrated how a change in the type of CNT to make the film affects its electrical performance. As the temperature was decreased down to cryogenic conditions, up to a 56-fold increase in resistance was noted. Moreover, the measurement of magnetoresistance (MR) revealed a non-monotonic dependence on the applied magnetic field. The initial negative component of MR was eventually overpowered by the positive MR component as the field strength was increased beyond a certain threshold.