According to a study conducted in 2021 by National Geographic, around 3.4 billion single-use facemasks are discarded daily, resulting in 1.6 million tons of plastic waste.
Atmospheric pressure plasma jets generated using noble gases have been the focus of intense investigation for over 2 decades due to their unique physicochemical properties and their suitability for ...treating living tissues to elicit a controlled biological response. Such devices enable the generation of a non-equilibrium plasma to be spatially separated from its downstream point of application, simultaneously providing inherent safety, stability and reactivity. Underpinning key plasma mediated biological applications are the reactive oxygen and nitrogen species (RONS) created when molecular gases interact with the noble gas plasma, yielding a complex yet highly reactive chemical mixture. The interplay between the plasma physics, fluid dynamics and plasma chemistry ultimately dictates the chemical composition of the RONS arriving at a biological target. This contribution reviews recent developments in understanding of the interplay between the flowing plasma, the quiescent background and a biological target to promote the development of future plasma medical therapies.
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To protect electronic systems against high-power microwave (HPM), a plasma waveguide limiter is presented. In response to the above phenomenon, a self-consistent 3-D multiphysics ...electromagnetic-plasma fluid model coupling full-wave Maxwell's equations with plasma fluid equations is established to describe the operating mechanism of a 3-D simplified sandwich structure plasma limiter filled with four easily ionized inert gases. The plasma limiter system is analyzed with the spectral-element time-domain (SETD) method. The choice of filling easily ionizable inert gas, influence of the number of layers, and pressure on the plasma limiter are discussed. Numerical results demonstrate that the gas with low critical breakdown field strength is more suitable for protecting HPMs. In the case of 20 torr, the order of microwave breakdown is xenon, argon, neon, and helium, and the two-layer plasma limiter (plasma-slab-plasma) has better protective characteristics than a one-layer plasma limiter (slab-plasma-slab) with the same length of gas chamber. Our research can provide theoretical guidance for designers and give the complete physical physics process.
Here, we present the first local, quantitative measurements of ion current filamentation and magnetic field amplification in interpenetrating plasmas, characterizing the dynamics of the ion Weibel ...instability. The interaction of a pair of laser-generated, counterpropagating, collisionless, supersonic plasma flows is probed using optical Thomson scattering (TS). Analysis of the TS ion-feature revealed anticorrelated modulations in the density of the two ion streams at the spatial scale of the ion skin depth c/ωpi = 120 μm, and a correlated modulation in the plasma current. The inferred current profile implies a magnetic field amplitude ~30 ± 6 T , corresponding to ~1% of the flow kinetic energy, indicating that magnetic trapping is the dominant saturation mechanism.
Atmospheric pressure plasma jets have the distinctive ability to project a plasma away from its electrodes, making it an attractive plasma source for a variety of surface treatment applications. ...Unfortunately, the small effective area of plasma jets inhibits their more widespread use. To remedy this, multiple plasma jets can be used in tandem to enhance their effective area. When used together, the plasma jets will interact and alter one another's properties. The goal of this work is to understand the interaction between plasma jets and use this interaction to influence their properties at the plasma-surface interface by tailoring the voltage waveforms driving two interacting plasma jets. In this work, two piezoelectric-driven plasma jets are positioned at a 130° angle from one another such that they will intersect on the surface of a substrate. The phase difference between the high-voltage waveforms generating the plasma jets was varied to manipulate the properties of the resultant plasma. It was found that increasing the phase difference between the plasma jets required less total power than when the two jets were operated independently and caused changes to the emission spectrum and an increase in the electron density at their intersection point. As such, changing the phase between two plasma jets can be used to alter the power consumption, the electron density, and the electron kinetics of the plasma at the surface of a substrate, which may be useful for a variety of applications.
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