4,5-DIHYDRO-4,4,5,5-TETRAMETHYL-2-PHENYL-1H-IMIDAZOL-1-YLOXY-1-OXIDE; 2-PHENYL-4,4,5,5-TETRAMETHYLIMIDAZOLINE-1-OXYL-3-OXIDE; 2-PHENYL-4,4,5,5-TETRAMETHYLIMIDAZOLINE-3-OXIDE-1-OXYL; 2-Phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl)[stablefreeradicalreagentforthesimultaneousdetermin; PTIO (2-PHENYL-4,4,5,5-TETRAMETHYLIMIDAZOLINE-3-OXIDE-1-OXYL); PTIO (=2-Phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl) [Stable free radical reagent for the simultaneous determination of NO and NO2 in the atmosphere]; 4,4,5,5-tetramethyl-2-phenyl-4,5-dihydro-1H-imidazol-1-ol 3-oxide; (4,4,5,5-tetramethyl-3-oxido-2-phenyl-4,5-dihydro-1H-imidazol-1-yl)oxidanyl