“Nitric-Acid-Activated Biochars from Agricultural Wastes for Methylene Blue Removal: Characterization and Pseudo-Second-Order Adsorption Kinetics”. Vietnam Journal of Catalysis and Adsorption, vol. 15, no. 3, Sept. 2026, pp. 29-35, https://doi.org/10.62239/jca.2026.042.