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High mobility and toxicity of arsenic [As (III)] limit its removal from an aquatic environment and pose a threat to human health. In this work, batch adsorption experiments were conducted to investigate the adsorption capacity of bismuth-impregnated aluminum oxide (BiAl). Continuous application of As (III) removal was achieved via a lab-scale column reactor. Bismuth impregnation decreased the specific surface area of aluminum oxide and affected its pore size distribution. However, because of its abundant and well-proportioned mesoporous character, it also enhanced its adsorption capacity through the surface complexation of As (III). Batch adsorption experiments demonstrated a suitable Freundlich model and a fitted pseudo-second-kinetic model for As (III) adsorption. The main mechanism was chemisorption with both bismuth and aluminum atoms; however, physisorption also contributed to arsenic adsorption at the initial stage of the reaction. The Adams-Bohart model better described the breakthrough curves than the Thomas model. BiAl exhibited efficient As (III) adsorption over a wide pH range and could be applied to As (III) removal from wastewater. A high As (III) removal efficiency (91.6%) was obtained at an initial As (III) concentration of 5 mg L −1 at a flow rate of 1 mL min -1 . This study indicates the potential for the practical application of BiAl in As (III) removal. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to study the effects of nutrient and water regimes on lodging resistance of rice plant by measuring and comparing the morphological and physical traits and the K2O and SiO2 contents of rice basal stems. The results indicated that a combined application of chemical fertilizers and organic materials, especially and rice straw (CS), could markedly increase the diameter, wall thickness and weight of basal stems, but reduce plant height, which resulted in the effective increase of snapping resistance (RS) and marked decrease of lodging index (LI). The effectiveness of the combined application of chemical fertilizers and rice straw (CS) on the increase of lodging resistance of rice plant was greater in alternate wetting and drying (AWD) and controlled irrigation (DRA), compared to continuous waterlogging (CWL). In addition, the combined application of chemical fertilizers and organic sources, especially with rice straw (CS), greatly increased the K2O and SiO2 contents in rice basal stems, especially in alternate wetting and drying (AWD) and controlled irrigation (DRA). Correlation analysis showed that the wall thickness, weight and snapping resistance of basal stems were significantly positively correlated to the K2O and SiO2 contents in rice basal stems (P<0.05 or P<0.01) in alternate wetting and drying (AWD) and controlled irrigation (DRA).