Revistas

A glow nanosecond discharge from a plane-to-plane impulse dielectric barrier discharge (iDBD) with ammonia gas has been characterised by employing fast imaging and electrical diagnostics. More precisely, the aim of this study is to investigate the dynamics of the discharge establishment under various conditions of applied voltage, pressure, and gas gap. The comparison between the current measurements and the image analysis exposes a strong correlation between the fast excitation and ionization wave velocity and the rising current velocity. This correlation has been found only for diffuse mode discharge since a front wave could be clearly defined, denoted as the luminous propagation front (LPF). Furthermore, this correlation is supported by a proportionality factor of 1.5 10$^{-3}$ which is systematic over the studied conditions. Further investigations are considered to evaluate the relevance of such a value over more parameters.

Jean-Marie-Desiree, Ronny

Surface dielectric barrier discharges (SDBDs) operating in atmospheric air are efficient sources of reactive oxygen and nitrogen species (RONS), making them promising candidates for food decontamination applications. However, their chemical output strongly depends on operating conditions and environmental humidity that can affect treatment efficacy and reproducibility. In this work, we characterize the transition between ozone-dominant (O3 mode) and nitrogen-oxidesdominant (NOX mode) operating regimes by combining ICCD imaging, optical emission spectroscopy, and time-resolved absorption measurements of O3 and NO2 . We demonstrate that an increase of the applied voltage and the dielectric temperature accelerates the shift from net ozone production to rapid O₃ destruction driven by NOx catalytic cycles, while water vapor further suppresses ozone formation through enhanced OH-and H-driven reactions. Spatiotemporal ICCD measurements reveal that humidity simultaneously modifies streamer morphology and enhances overall plasma intensity. These findings establish quantitative operating windows to control RONS production for applications requiring either oxidative (O3 -rich) or nitrosative (NOx -rich) biocidal environments, providing essential knowledge for optimizing plasma-based food safety technologies.

Aliyeva, Zh