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We study the bactericidal efficacy of surface dielectric barrier discharge low-temperature plasma treatments, powered by nanosecond high voltage pulses. We achieve ∼ 4-log reduction in Escherichia coli population, after 10 min treatments, at a distance of 1.5 cm from the plasma surface. To investigate the reactive oxygen and nitrogen species (RONS) responsible for the bactericidal effect, we employ in-situ fourier transform infrared (FTIR) spectroscopy to measure a selection of relevant species, such as O 3 , NO 2 , N 2 O and N 2 O 5 . The measurements are taken under various relative humidity conditions to replicate the bacteria treatment environment. While RONS originating from nitrogen chemistry are detected, nitric oxide (NO), a pivotal molecule in nitrate production, is absent due to the sensitivity limitations of FTIR detection. To overcome this limitation, we employ laser induced fluorescence utilizing a picosecond-pulsed laser to measure the kinetics of NO produced by the plasma. Our results show that the NO concentration is smaller than 1 ppm and primarily localized near the plasma surface, with concentrations increasing proportionally with relative humidity. Notably, at a distance of 1.5 cm from the plasma surface, at which the E. coli is treated, the concentration of NO falls below 50 ppb. Although NO is pivotal in generating secondary reactive species within the plasma, our results suggest that it does not directly contribute to the bacteria inactivation process. Instead, other molecules, such as O 3 , NO 2 , and N 2 O, which are found in higher concentrations, may be responsible for the bactericidal properties observed in indirect plasma treatments. [ABSTRACT FROM AUTHOR]

Plasma treatments are currently being assessed as a seed processing technology for agricultural purposes. There is sufficient information as a proof‐of‐concept, but a lack of standardization in the methodology prevents a convincing evaluation of plasma treatment on seeds. It would be helpful to coordinate research efforts to make the entry for newcomers into this interdisciplinary field less overwhelming and to aid in transferring this technology into the industry by establishing a common protocol. This review presents the parameters used in the seed preparation, the plasma treatment of the seed, and the seed posttreatment. This summary of the plasma and biological parameters is intended to raise awareness about questions that need to be addressed to properly record protocol details and reproduce results for the plasma treatment of seeds. [ABSTRACT FROM AUTHOR]

The increasing importance of providing reliable polarimetric measurements in real time, for both machine protection and plasma control, has motivated the development of a quick version of the calibration algorithms for JET polarimeter. This new code, which interprets the calibration procedure performed before each shot, is based on a physical equivalent model of the diagnostic optical path and is valid for any operational regime of JET. It provides results before the plasma breakdown, and, with its estimates of the optical paths parameters, the polarimetric measurements have an accuracy more than sufficient for real-time purposes. New approximate equations have been validated in order to obtain the line integrated density from the newly calibrated horizontal chords, so that also these polarimetric measurements can also be used for density feedback and machine protection. The availability of reliable polarimetric measurements in real time opens new perspectives also to the determination of the plasma boundary, the magnetic equilibrium, and their use in advanced feedback control schemes. [ABSTRACT FROM AUTHOR]