Spectral distribution of the radiochemiluminescence from gamma-irradiated humic acid

This study was conducted to investigate radiochemiluminescence (RCL) spectra (340-650 nm), kinetics and absorption spectra of humic acids (HA) after their exposure of gamma-radiation (absorbed doses of 1-10 kGy, 60Co) in model systems. The kinetics and spectral distribution of RCL were measured using the single photon counting method (SPC) and cut-off filters. Absorption spectra (range 240-800 nm) of irradiated solutions indicated that post-radiative degradation/polymerization processes take place in the HA changing their macromolecule or properties. The intensity of the delayed RCL was nonlinearly and suggested that complex radical formation mechanisms were still involved in the post-radiative reactions. (author)