Plasma and Aerosols: Challenges, Opportunities and Perspectives (original) (raw)
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The Role of Interfacial Reactions in Determining Plasma–Liquid Chemistry
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Biointerphases, 2015
The mechanism of interaction of cold nonequilibrium plasma jets with mammalian cells in physiologic liquid is reported. The major biological active species produced by an argon RF plasma jet responsible for cell viability reduction are analyzed by experimental results obtained through physical, biological, and chemical diagnostics. This is complemented with chemical kinetics modeling of the plasma source to assess the dominant reactive gas phase species. Different plasma chemistries are obtained by changing the feed gas composition of the cold argon based RF plasma jet from argon, humidified argon (0.27%), to argon/oxygen (1%) and argon/air (1%) at constant power. A minimal consensus physiologic liquid was used, providing isotonic and isohydric conditions and nutrients but is devoid of scavengers or serum constituents. While argon and humidified argon plasma led to the creation of hydrogen peroxide dominated action on the mammalian cells, argon-oxygen and argon-air plasma created a ...
Physical chemistry chemical physics : PCCP, 2018
The understanding of plasma-liquid interactions is of major importance, not only in physical chemistry, chemical engineering and polymer science, but in biomedicine as well as to better control the biological processes induced on/in biological samples by Cold Atmospheric Plasmas (CAPs). Moreover, plasma-air interactions have to be particularly considered since these CAPs propagate in the ambient air. Herein, we developed a helium-based CAP setup equipped with a shielding-gas device, which allows the control of plasma-air interactions. Thanks to this device, we obtained specific diffuse CAPs, with the ability to propagate along several centimetres in the ambient air at atmospheric pressure. Optical Emission Spectroscopy (OES) measurements were performed on these CAPs during their interaction with a liquid medium (phosphate-buffered saline PBS 10 mM, pH 7.4) giving valuable information about the induced chemistry as a function of the shielding gas composition (variable O2/(O2 + N2) ra...
Nanotechnology and Precision Engineering, 2019
This study reports the development and performance of a pilot-scale barrel atmospheric plasma reactor for the atmospheric plasma activation treatment of polymer particles. The polymer particles treated included acrylonitrile butadiene styrene (ABS) and polypropylene (PP). These particles had diameters in the range of 3–5 mm. The initial studies were carried out using a laboratory-scale barrel reactor designed to treat polymer particle batch sizes of 20 g. A pilot-scale reactor that could treat 500 g particle batch sizes was then developed to facilitate pre-industrial-scale treatments. The effect of operating pulse density modulation (PDM) in the range 10%–100% and plasma treatment time on the level of activation of the treated polymers were then investigated. ABS revealed a larger decrease in water contact angle compared with PP after plasma treatment under the same conditions. The optimal treatment time of ABS (400 g of polymer particles) in the pilot-scale reactor was 15 min. The ...