Abdul-Aziz, Yasser, and Zainab Hassan. “Synthesis Eco-Friendly Biochar from Spent Coffee for Using to Remove Acidic and Basic Dyes from Aqueous Media”. Al-Nahrain Journal for Engineering Sciences, vol. 29, no. 2, July 2026, pp. 353-6, https://doi.org/10.29194/NJES.29020353.