Non-thermal plasma multi-jet platform based on a flexible matrix

On Encapsulated Dielectric Barrier Discharge Plasma Sources for Radar Cross Section Reduction in Mobile Environments

This paper deals with the practical application of Radar Cross Section (RCS) reduction technology using plasma. Although various plasma application technologies for RCS reduction have been studied, there are still many issues to be addressed for practical implementation. In order to achieve actual application, the discharge should be sustained regardless of the external environment of the aircraft. It is also important to investigate the actual plasma parameters to determine the expected RCS reduction effect. Building upon previous studies that optimized the electrodes for RCS reduction, this study fabricates a Dielectric Barrier Discharge (DBD) source suitable for dynamic environments and verifies the power consumption during one cycle of plasma generation. The obtained results are expected to contribute to the optimization of DBD electrodes for plasma RCS reduction.

Current Status and Future Trends of Cold Atmospheric Plasma as an Oncotherapy

Cold atmospheric plasma (CAP), a redox modulation tool, is capable of inhibiting a wide spectrum of cancers and has thus been proposed as an emerging onco-therapy. However, with incremental successes consecutively reported on the anticancer efficacy of CAP, no consensus has been made on the types of tumours sensitive to CAP due to the different intrinsic characteristics of the cells and the heterogeneous design of CAP devices and their parameter configurations. These factors have substantially hindered the clinical use of CAP as an oncotherapy. It is thus imperative to clarify the tumour types responsive to CAP, the experimental models available for CAP-associated investigations, CAP administration strategies and the mechanisms by which CAP exerts its anticancer effects with the aim of identifying important yet less studied areas to accelerate the process of translating CAP into clinical use and fostering the field of plasma oncology.

Flexible Cold Atmospheric Plasma Jet Sources

The properties of non-thermal atmospheric pressure plasma jets (APPJs) make them suitable for industrial and biomedical applications. They show many advantages when it comes to local and precise surface treatments, and there is interest in upgrading their performance for irradiation on large areas and uneven surfaces. The generation of charged species (electrons and ions) and reactive species (radicals), together with emitted UV photons, enables a rich plasma chemistry that should be uniform on arbitrary sample profiles. Lateral gradients in plasma parameters from multi-jets should, therefore, be minimized and addressed by means of plasma monitoring techniques, such as electrical diagnostics and optical emission spectroscopy analysis (OES). This article briefly reviews the main strategies adopted to build morphing APPJ arrays and ultra-flexible and long tubes to project cold plasma jets. Basic aspects, such as inter-jet interactions and nozzle shape, have also been discussed, as well as potential applications in the fields of polymer processing and plasma medicine.

Flexible plasma multi-jet source operated in radial discharge configuration

Following up on a recent study describing a flexible plasma source operated in planar geometry, the performance of a cold atmospheric plasma jet (CAPJ) matrix emanating radially from a soft cylindrical surface in the open air is presented. The plasma device, which has a set of small outlets produced in its side surface, has a length of 12 cm and an outer diameter of 5.4 cm. The dielectric barrier discharge (DBD) sustaining the plasma jets is generated in helium flowing between two coaxial electrodes, which are separated by both an insulating tape and a cylindrical wall made of polymer foam. Two operation modes are considered: four equidistant CAPJs at the same axial position (round brush mode) and three aligned CAPJs at constant azimuthal angle (comb mode). All discharges, excited by 15 kHz-AC voltages at 3.8 kV in amplitude, have resulted in uniform lengths and intensities of the jets. Consumed discharge powers of between 0.1 and 1.5 W have been estimated from current-voltage measurements. Optical emission spectroscopy has shown the preponderance of hydroxyl groups, nitrogen molecules, and helium atoms in the active DBD region and the jet afterglow zone. This new design of CAPJ anticipates promising applications for treating the inner surface of hollow and delicate components for activation or healing purposes.