Thermotolerant yeasts are widely considered to be alternative strains to traditional yeasts for bioethanol production at high temperatures. In this study, thirty-two yeasts isolated from lychees were screened for thermotolerance, and seven selected isolates were identified as Candida tropicalis (isolates H8, H19, and H23), Meyerozyma guilliermondii (isolates H1 and H12) and Saccharomyces cerevisiae (isolates H10 and H18). They tolerated up to 45 °C, 12% (v/v) ethanol concentration, 10 g/L acetic acid, and 5 g/L furfural, respectively, and produced 47.96 to 70.18 g/L of ethanol from 160 g/L glucose at 40 °C during 48 h of fermentation. Among the evaluated yeasts, M. guilliermondii H1 showed great potential for second-generation bioethanol fermentation with its ability to ferment xylose and arabinose. Under the optimal conditions resulting from a Plackett Burman design and a Box Behnken design, the highest ethanol concentration of 11.12 g/L was produced from 40 g/L substrate-based sugarcane bagasse hydrolysate (non-detoxified hydrolysate) at 40 °C by M. guilliermondii H1. These findings suggested that the newly isolated thermotolerant yeast M. guilliermondii H1 is a good candidate for ethanol production from agricultural wastes.

This study is aimed at exploring the effects of SiO₂ nanoparticles on the crosslinking and mechanical and thermal properties of UV curing acrylic epoxy coating. The curing polymerization process and thermal and mechanical properties of UV-curable acrylate epoxy system have been evaluated with or without the presence of SiO₂ nanoparticles. To fabricate the UV curing acrylic epoxy/SiO₂ nanocomposite coating, nano-SiO₂ particles (0.55wt. by weight of resin) were added in the photo-curable system using sonication for 3h. Various techniques for characterization have been used, such as FESEM (field emission scanning electron microscope), FTIR (Fourier-transform infrared spectroscopy), TGA (thermogravimetry analysis), gel fraction, and swelling degree analyses. FESEM data indicated that at the content of 2.5wt., nanosilica was homogeneously dispersed in the coating procedure. However, once added 5wt., large aggregation portions were found inside the coating matrices. Surprisingly, nano-SiO₂ could play dual roles, as both UV absorbers and nanoreinforcers, in this nanocomposite coating. Besides, data from FTIR, gel fraction, and swelling degree analyses confirmed the role of SiO₂ nanoparticles as UV absorbers that reduced the conversion performance of acrylate double bonds, thus increased slightly the swelling degree of coating. In addition, incorporation of SiO₂ nanoparticles (as nanofillers, at content of 2.5wt.) in the polymer matrix enhanced significantly the abrasion resistance and thermal stability of the coating, by 60 (from 98.3 to 158.4 lite/mil) and 9C (from 348C to 357C), respectively.