| Abstract
| - The kinetics of the reactions of hydroxyl radical with n-octane (k1), n-nonane (k2), and n-decane (k3) at 240−340 K and a total pressure of ∼1 Torr has been studied using relative rate combined with discharge flow andmass spectrometer (RR/DF/MS) technique. The rate constant for these reactions was found to be positivelydependent on temperature, with an Arrhenius expression of k1 = (2.27 ± 0.21) × 10-11exp[(−296 ± 27)/T],k2 = (4.35 ± 0.49) × 10-11exp[(−411 ± 32)/T], and k3 = (2.26 ± 0.28) × 10-11exp[(−160 ± 36)/T] cm3molecule-1 s-1 (uncertainties taken as 2σ), respectively. Our results are in good agreement with previousstudies at and above room temperature using different techniques. Assuming that the reaction of alkane withhydroxyl radical is the predominant form for loss of these alkanes in the troposphere, the atmospheric lifetimefor n-octane, n-nonane, and n-decane is estimated to be about 43, 35, and 28 h, respectively.
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