This study investigated the durability of alkali-activated binders based on blends of fly ash (FA) and ground granulated blast furnace slag (GGBFS). Five fly ash-to-slag ratios of 100/0, 75/25, 50/50, 25/75, and 0/100 by mass were selected to produce alkali-activated fly ash/slag (AAFS) concrete. Sodium oxide (Na2O) concentrations of 6% and 8% of binder weight and activator modulus ratios (mass ratio of SiO2 to Na2O) of 0.8, 1.0, and 1.23 were used as alkaline activators. Test results show that the total charge passed of AAFS concrete is between 2500 and 4000 coulombs, higher than the comparable OPC concrete. However, AAFS concrete exposed to sulfate attack performed better than OPC concrete. Based on the results, 100% slag-based AAFS concrete with Na2O concentration of 8% and activator modulus ratio of 1.23 has the superior performances.

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ZnO nanoflakes were grown on the lead (Pb) plates using the electro- hydrothermal deposition methods. To investigate the influence of electrodeposition current, the ZnO seed layer was electrodeposited on the lead plates at a larger current of 160 mA (current density of 40 mA/cm2) and a smaller current of 12 mA (current density of 3mA/cm2), respectively. Then, ZnO nanoflakes were grown on top of the seed layer. Multiple analyses including field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), photoluminescence (PL) were performed on the ZnO nanostructures/Pb plates. Furthermore, surface con-tact angle measurements were conducted to study the hydrophobic properties and OD 600 antibacterial tests were used to investigate the antiseptic effects. Results indicate that the ZnO nanoflakes with the seed layer grown at a lower current of 12 mA exhibited good hydrop-hobic properties and strong antibacterial effects. ZnO nanoflakes/Pb plates show promising for future anti-radiation, antibacterial, and waterproof lead clothing applications.

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