本文研究不同PH和去氧对数种哌啶系氮氧自由基在溶液中的ESR波谱的影响。其中两种水溶性自由基在PH为3-12的缓冲液内,有较高稳定性。对固态自由基,去氧并不影响其ESR特性,但在自由基溶液中,溶剂极性对如何显现去氧效应起着决定性的作用。在低极性溶液中,去氧使波谱显著变窄及增强,~(14)N超精细三峰分裂的完善程度大大提高;而在水溶液中,去氧效应甚小。 In this paper, the effects of different pH and deoxygenation on the ESR spectra of several piperidine nitroxides in solution were investigated. Two of the water-soluble free radicals in the PH 3-12 buffer, a higher stability. For solid free radicals, deoxygenation does not affect its ESR properties, but in free radical solutions, solvent polarity plays a decisive role in how deoxygenation occurs. In low polar solution, deoxygenation significantly narrowed and enhanced the spectrum, and the perfection of ~ (14) N hyperfine triplet peak splitting increased greatly. However, the deoxygenation effect was very small in aqueous solution.