Partners

Abstract:
The shortage of face masks and the lack of antipathogenic functions has been significant since the recent pandemic's inception. Moreover, the disposal of an enormous number of contaminated face masks not only carries a significant environmental impact but also escalates the risk of cross-contamination. This study proposes a strategy to upgrade available surgical masks into antibacterial masks with enhanced particle and bacterial filtration. Plasmonic nanoparticles can provide photodynamic and photothermal functionalities for surgical masks. For this purpose, gold nanorods act as on-demand agents to eliminate pathogens on the surface of the masks upon near-infrared light irradiation. Additionally, the modified masks are furnished with polymer electrospun nanofibrous layers. These electrospun layers can enhance the particle and bacterial filtration efficiency, not at the cost of the pressure drop of the mask. Consequently, fabricating these prototype masks could be a practical approach to upgrading the available masks to alleviate the environmental toll of disposable face masks.

Abstract:
Supersulfated cement (SSC) is a traditional low-carbon cement, but its slow hydration and strength development has limited its practical applications. Nano silica (NS) was used to activate the hydration of SSC by taking advantage of its ability to regulate silicate and aluminate reactions. The mechanical performance of various mixes was determined, as a function of sulfation degree and NS addition, as pore structure, phase assemblage, hydration degree, and microstructure. Results showed that NS improves the hydration degree of slag, densifies the microstructure, and significantly increases both early- and late-age compressive strength. The enhancement was attributed to its effects on the hydration of slag in SSC: delaying ettringite formation, but promoting C-(A)-S-H precipitation, reducing microporosity. This study reveals the critical role of the regulation of hydration kinetics of silicate and aluminate in controlling the performance of SSC as NS does.

Keywords:
Supersulfated cement, Nano silica, Gypsum content, Mechanical property, Microstructure

Abstract:
A novel solution combustion synthesis of nanoscale spinel-structured Co3O4 powder was proposed in this work. The obtained material was composed of loosely arranged nanoparticles whose average diameter was about 36 nm. The as-prepared cobalt oxide powder was also tested as the anode material for Li-ion batteries and revealed specific capacities of 1060 and 533 mAh·g^−1 after 100 cycles at charge–discharge current densities of 100 and 500 mA·g^−1, respectively. Moreover, electrochemical measurements indicate that even though the synthesized nanomaterial possesses a low active surface area, it exhibits a relatively high specific capacity measured at 100 mA·g^−1 after 100 cycles and a quite good rate capability at current densities between 50 and 5000 mA·g^−1.

Keywords:
anode material, cobalt oxide, lithium-ion battery, solution combustion synthesis, transition metal oxide