Optical emission spectroscopy was used to study the glow discharge of CO2 in the pressure range of 0.2 to 1.2 mTorr, power of 160 W and a flux of 35 psi. The emission bands and lines were measured using a monochromator in the wavelength range of 200 to 900 nm. The species observed were C2 (A3Πg – X'3Πu) at 435.7nm and (C'1Πg – b1Πu) at 369.2 nm; O2 (b1Σg+ ‐ X3Σg–) at 628.2; CO (a'3Σ ‐ a3Π) at 674.7 nm; O2+ (A2Πu ‐ X2Πg) at 339.3 and 289.2 nm; CO2+ (A2Π ‐ X2Π) at 353.2 nm; CO2 (1B2 – X1Σ+) at 391.7 nm; CO+ (A2Π – X2Σ) at 577.7 nm; and O3 (1B2 – X1A1) at 327.2 nm. We observed that the emission intensities bands have an almost constant behavior as function of the pressure in the range of 0.2 to 0.6 mTorr, followed by an increasing behavior. The electron temperature and ion density were determined by a double Langmuir probe. The electron temperature was found of 8.53 eV, and the electron concentration of 7.11 x 109 cm–3 at a pressure of 0.8 mTorr. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Optical emission spectroscopy was used to study a gas mixture glow discharge of CO2 and N2 at a total pressure of 1.2 Torr, a power of 100 W and a flow of 16.5 L/min. The emission bands were measured in the wavelength range of 200 nm to 900 nm. The principal species observed were O, and CO (a 3 Σ → a 3 Π). The behavior of the band intensities as a function of the N2 percentage is consistent with recent Monte Carlo simulations. The electron temperature and ion density were determined by a double Langmuir probe. The electron temperature was found in the range of 1.55 eV to 2.93 eV, and the electron concentration in the order of 10 10 cm −3 . The electron temperature and ion density at pure N2 and pure CO2 agree with previous measurements.

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We describe the entropy of liquids in the context of kinetic theory of dense gases. In the equilibrium regime the statistical entropy has an explicit dependence of the pair correlation function. In order to test the entropy functional, we use the Morse potential to reproduce experimental pair correlation functions of liquid sodium, using the molecular dynamics technique. With this information, we can compare the theoretical entropy with experimental thermodynamic data. On the other hand, from the nonequilibrium point of view, we discuss the entropy-increase-law analyzing the entropy balance equation. The entropy production due to the molecular diffusion processes displays an upper bound which is proportional to the so-called Fisher information. In the regime at which the one-particle distribution function only depends on particles momentum and time, we show that the factor of proportionality which appears in the upper bound is essentially the time integral of the force autocorrelation function between particles. Besides the parameters of the interparticle potential found through molecular dynamics simulations, we find the time scale of particles’ thermalization and therefore the approach to equilibrium for the system.

SARS-CoV-2 is responsible for causing the Coronavirus disease 2019 (COVID-19) pandemic, which has so far infected more than thirty million people and caused almost a million deaths. For this reason, it has been a priority to stop the transmission of the outbreak through preventive measures, such as surface disinfection, and to establish bases for the design of an effective disinfection technique without chemical components. In this study, we performed in silico analysis to identify the conformational alterations of the SARS-CoV-2 Spike Receptor Binding Domain (RBD) caused by the effect of a pulsed electric field at two different intensities. We found that both stimuli, especially the one with the highest angular frequency and amplitude, modified the electrical charge distribution in the RBD surface and the number of hydrogen bonds. Moreover, the secondary structure was significantly affected, with a decrease of the structured regions, particularly the regions with residues involved in recognizing and interacting with the receptor ACE2. Since many regions suffered conformational changes, we calculated RMSF and ΔRMSF to identify the regions and residues with larger fluctuations and higher flexibility. We found that regions conformed by 353-372, 453-464, and 470-490 amino acid residues fluctuate the most, where the first is considered a therapeutic target, and the last has alreadybeen characterized for its flexibility. Our results indicate that a pulsed electric field can cause loss of stability in the Spike-RBD, and we were able to identify the vulnerable sites to be used as a starting point for the development of viral inhibition or inactivation mechanisms.