Regulation of angiotensin-converting enzyme 2 isoforms by type 2 inflammation and viral infection in human airway epithelium

The effect of the early strength agent named calcium silicate hydrate polycarboxylate ether nanocomposite (C-SH seed), fly ash and slag on the development of microstructure, autogenous deformation and durability, as well as the mechanism of interaction between microscopic (e.g., pore structure) and macroscopic properties of concrete, were investigated. Results showed that C-S-H seed increased the compressive strength of concrete before 7 d. The addition of C-S-H seed decreased both relative humidity and capillary pore diameter due to rapid hydration, which resulted in high negative capillary pressure and autogenous deformation of up to 40%. The higher fly ash and slag contents decreased early-age autogenous deformation. Further analysis showed that the addition of C-S-H seed decreased the percentage of pores>1000 nm and the most probable pore diameter of concrete, thus increasing resistance to chloride migration into concrete. The chloride diffusion coefficient was linearly related to the amount of cementitious material together with the water-to-binder ratio. The C-S-H seed decreased the availability of pores of critical diameter (14 nm) of concrete exposed to water freezing, leading to an increase in the freeze-thaw resistance of concrete. In addition, the C-S-H seed also reduced the overall porosity of concrete, leading to an increase in resistance to sulfate attack. Similar trends were observed for increased fly ash and slag content. Besides, the concentrations of AP and Ca2+ significantly affected sulfate resistance.