Intensification of heat and mass transfer of the gas channel of the multi-temperature condensation filter

The principle of operation and features of hydrodynamics and heat-mass transfer in the working channel of a multi-temperature condensation filter for gas purification are described. Promising methods of gas flow purification using porous surfaces are described. The modeling and comparison of the laminar air flow in channels of various shapes: in a flat channel, in a channel with webs and in a spiral channel are performed. An analysis of their effectiveness is carried out.

Porous surfaces: stability and recovery of coronaviruses

The role of indirect contact in the transmission of SARS-CoV-2 is not clear. SARS-CoV-2 persists on dry surfaces for hours to days; published studies have largely focused on hard surfaces with less research being conducted on different porous surfaces, such as textiles. Understanding the potential risks of indirect transmission of COVID-19 is useful for settings where there is close contact with textiles, including healthcare, manufacturing and retail environments. This article aims to review current research on porous surfaces in relation to their potential as fomites of coronaviruses compared to non-porous surfaces. Current methodologies for assessing the stability and recovery of coronaviruses from surfaces are also explored. Coronaviruses are often less stable on porous surfaces than non-porous surfaces, for example, SARS-CoV-2 persists for 0.5 h–5 days on paper and 3–21 days on plastic; however, stability is dependent on the type of surface. In particular, the surface properties of textiles differ widely depending on their construction, leading to variation in the stability of coronaviruses, with longer persistence on more hydrophobic materials such as polyester (1–3 days) compared to highly absorbent cotton (2 h–4 days). These findings should be considered where there is close contact with potentially contaminated textiles.