Secondary radical Second-order rate constant

The corresponding reaction with titaniura(iii) in excess exhibited second-order behaviour, the production of OH radicals as intermediates being confirmed by the addition of propan-2-ol, which reacts rapidly with HO and thereby decreased (by a factor of 2) the rate of decay of reductant. Confirmation that any secondary rate constants (k are much greater than that for the ratedetermining initial step have been derived from a study of the reductants with hydroxyl radicals. The values for the reactions of Cr and Ti f are 1.2 x 10 ... 

Whenever possible the fourth point has been taken into consideration and radical concentrations have been corrected for losses due to recombination or other decay reactions of the (secondary) radicals under consideration. In the case of 6 polyamide fibers [5, 11, 17, 18] the radical decay is a second order recombination reaction with the rate constant depending on type, location, and mobility of the radicals (see Section III below). 

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