Fully bio-based epoxy resins from lignin and epoxidized soybean oil: Rigid-flexible, tunable properties and high lignin content.

The application of epoxidized soybean oil (ESO) in thermosetting polymers is impeded by its unsatisfactory thermomechanical properties. Here, in order to address the limitation, technical lignin was modified by tung oil anhydride and then used as the hardener to compensate for the inherent flexibility defects of ESO thermosets (TLs). As the lignin content increased, a notable improvement in the activation energy of TLs was observed, attributed to the restraining effect of lignin's rigid structure on segmental relaxation. Concurrently, the tensile strength of TLs increased from 2.8 MPa to 34.0 MPa, concomitant with a decrease in elongation at break from 32.9 % to 8.0 %. Comparative analysis with TL-0 (devoid of lignin) demonstrated substantial enhancements in glass transition temperature, shape fixation ratio, and shape recovery ratio for TL-50 (comprising 50 wt% of lignin), elevating from 16.9 °C, 89.1 %, and 89.5 % to 118.6 °C, 94.0 %, and 99.3 %, respectively. These results unequivocally highlight the favorable dynamic mechanical and shape memory properties conferred upon TLs by lignin addition. While the introduction of lignin adversely affected thermal stability, a notable improvement in char yield (800 °C) was observed. Collectively, these findings underscore the potential of technical lignin as a promising bio-based curing agent for ESO.

Applications-oriented algicidal efficacy research and in-depth mechanism of a novel strain Brevibacillus sp. on Microcystis aeruginosa.

The utilization of algicidal bacteria for the control of harmful algal blooms (HABs) is a promising technology for ecological remediation. In our most recent publication, a novel strain of Brevibacillus sp. was isolated and proved to have significant algicidal activity and stability against Microcystis aeruginosa. In order to verify the algicidal effect of the strain in the practical application scenario, the algicidal efficacy of Brevibacillus sp. under conditions close to water in the environment was investigated. Results indicated that the algicidal threshold of Brevibacillus sp. culture was 3‰ inoculation concentration, and the removal rate of M. aeruginosa reached 100%. The process of Chl-a degradation followed a first-order kinetic model, which could be used to predict the degradation effect of M. aeruginosa in practical applications. Additionally, the inoculation of Brevibacillus sp. culture introduced additional nutrients, some of which remained in the water. Furthermore, the algicidal substances demonstrated good sustainability, with a removal rate of up to 78.53% at 144 h after three repeated uses. At 12 h, the algicidal substances caused a 78.65% increase in malondialdehyde (MDA) content in M. aeruginosa compared to the control group, thereby triggering the antioxidant system of M. aeruginosa. Moreover, algal cell fragments were observed to aggregate. This study provides a promising direction for treating cyanobacterial blooms using algicidal bacteria in practical applications.

Cu2O/hollow mesoporous silica composites for the rapid and efficient removal of methylene blue.

Cu2O/hollow mesoporous silica (HMS) composite was synthesized using HMS as supporting material by the impregnation method. This composite displayed integrated physicochemical performance of Cu2O and HMS, resulting in low density, large surface area and excellent dispersibility. The synthesized nano-sized composite of Cu2O/HMS demonstrated rapid and effective removal for methylene blue with an efficiency of 99.8% with the reaction time of 5 min. Moreover, the Cu2O/HMS composite exhibited high stability and present no obvious performance degradation after seven cycles. The dye removal efficiency stood up to 89% even after 15 cycles. The improved properties of Cu2O/HMS are possibly the account of the collaborative effect between the mesoporous adsorption with Cu2O photocatalysis.