Chemical-oxygen demands Chemical oxygen demand 2 Effluent treatment 2 Effluents 2 Wastewater treatment 2 Water quality 2 Activated sludge process 1 Analytes 1 COD 1 Carbon 1 Carbon electrode 1 Carbon-based 1 Chemical oxygen demand removal efficiency 1 China 1 Chlorine compounds 1 Copper 1 Copper-based 1 Cost effectiveness 1 Crystallinity 1 Cu or Cu2O-modified carbon electrodes 1 Cu or cu2O-modified carbon electrode 1 Efficiency 1 Effluent waters 1 Electrochemical electrodes 1 Electrochemical sensors 1 Fenton's reagents 1 Forecasting 1 Genetic algorithms 1 Initial solution 1 Input variables 1