Different Setup of Capacitive Coupling Protection System on Mild Steel

A Capacitive Coupling Corrosion Protection (CCCP) technology based on coupler pads was investigated. The layout of the coupler pads on the mild steel surface was studied to get the best outdoor corrosion protection. A square wave of current/voltage is supplied to the steel surface for 72 hours via a copper coupler pad in three arrangements, i.e., single, double-sided, and opposite configurations. The efficiency of the CCCP configuration was assessed by measuring electrical current consumption, weight loss, and post-experimental surface morphology observations. It is found that the current consumption of 600 μA/cm2 in the double-sided configuration is practically stable. The lowest weight loss and clean surface morphology also prove that the double-sided configuration can improve the corrosion protection of mild steel. It was discovered that by employing more coupling pads on both sides of the metal sheet, the excessive positive charge capable of producing oxidation of mild steel could be easily discharged.

Accurate Simulations of Lipid Monolayers Require a Water Model With Correct Surface Tension

Lipid monolayers provide our lungs and eyes their functionality, and serve as proxy systems in biomembrane research. Therefore, lipid monolayers have been studied intensively also using molecular dynamics simulations, which are able to probe their lateral structure and interactions with, e.g., pharmaceuticals or nanoparticles. However, such simulations have struggled in describing the forces at the air–water interface. Particularly the surface tension of water and long-range van der Waals interactions have been considered critical, but their importance in monolayer simulations has been evaluated only separately. Here we combine the recent C36/LJ-PME lipid force field that in- cludes long-range van der Waals forces with water models that reproduce experimental surface tensions to elucidate the importance of these contributions in monolayer simulations. Our results suggest that a water model with correct surface tension is necessary to reproduce experimental surface pressure–area isotherms and monolayer phase behavior, while standard cutoff-based CHARMM36 lipid model with the 4-point OPC water model still provides the best agreement with experiments. Our results emphasize the importance of using high quality water models in applications and parameter development in molecular dynamics simulations of biomolecules.

Atomistic Descriptions of Gas–Surface Interactions on Tin Dioxide

Historically, in gas sensing literature, the focus on “mechanisms” has been on oxygen species chemisorbed (ionosorbed) from the ambient atmosphere, but what these species actually represent and the location of the adsorption site on the surface of the solid are typically not well described. Recent advances in computational modelling and experimental surface science provide insights on the likely mechanism by which oxygen and other species interact with the surface of SnO2, providing insight into future directions for materials design and optimisation. This article reviews the proposed models of adsorption and reaction of oxygen on SnO2, including a summary of conventional evidence for oxygen ionosorption and recent operando spectroscopy studies of the atomistic interactions on the surface. The analysis is extended to include common target and interfering reducing gases, such as CO and H2, cross-interactions with H2O vapour, and NO2 as an example of an oxidising gas. We emphasise the importance of the surface oxygen vacancies as both the preferred adsorption site of many gases and in the self-doping mechanism of SnO2.

Estimation SARS-CoV-2 viability in time on experimental surfaces over

Infected SARS-CoV-2 virus occurs not only through contact with an infected person, but also through surfaces with wich the illnes has contacted. The problem of preserving an infectious virus over time capable of infecting remains actual. We evaluated the SARS-CoV-2 viability preservation on different model surfaces over time. Ceramic tiles, metal (aluminum foil), wood (chipboard), plastic and cloth (towel) were used as model materials. Assessment of the presence of SARS-CoV-2 RNA was carried out by quantitative RT-PCR. Viable virus was determined by tissue culture assay on 293T/ACE2 cells. It was found that the SARS-CoV-2 RNA was detected on all studied surfaces for 360 minutes, but a significant decrease RNA by 1 log10 copies/ml was detected after contact of the virus with cloth (towel). While the viability of the virus was completely lost after 120 minutes. Type of experimental surface significantly affects viability preservation.