single-crystal X-ray study T = 273 K mean σ(C-C) = 0.002 Å 2,2-diphenyl-1-picrylhydrazyl Biphenyl Compounds Crystal structure Crystallography, X-Ray Free Radical Scavengers Hydrazones Molecular Structure Picrates Superoxides X ray crystallography article biphenyl derivative chemical structure chemistry hydrazone derivative mean ω(C-C) = 0.003 Å picric acid scavenger superoxide synthesis wR factor = 0.124 1,1 diphenyl 2 picrylhydrazyl 2,4-dimethylbenzoylhydrazones 3,4-dimethoxybenzenamine Schiff bases 4-methoxybenzoylhydrazones AGEs Air-lift pumps; Multiple parallel lift tubes; Modelling; Predictions; Artificial neural network (ANN); 0906 Electrical and Electronic Engineering