Hydrogen atoms from the decomposition of hexamethylethane were reacted with chlorobenzene, o-dichlorobenzene, p-dichlorobenzene, and 1,2,3-trichlorobenzene in the presence of toluene or 1,3,5-1rimethylbenzene in single-pulse shock tube experiments. Using the rate expression for the displacement of the methyl group from the methylated aromatics as standards we find k(H + C6H5C1 -C6H6 + Cl) = (2.2 X 1010) exp(-4531/7) L/(mol-s), k(H + o-C6H4C12 -C6HSC1 + Cl) = (9.2 X 1010) exp(-5196/T) L/(mol-s), fc(H + p-C6H4Cl2 -C6H5C1 + Cl) = (4.6 X 1010) exp(-4541/T) L/(mol-s), /t(H + ,1,2,3-C6H3C13o-C6H4C1 + Cl) = (1.9 X 1010) exp(-2954/T) L/(mol-s), and k(H + 1,2,3-C6H3C13w-C6H4C1 + Cl) = (3.7 X 109) exp(-1856/7) L/(mol-s) at temperatures of 1050-1150 K and pressures between 2.5 and 3.2 atm. In this temperature range the relative rate constants on a per-chlorine basis for the five processes are 1:1.15:1.05:1.8:2.4. The absolute uncertainty in the rate expressions are of the order of 8 kj in the activation energy and a factor of 2.5 in the A factor. The relative rate constants have an uncertainty of no more than a factor of 1.1. Rate expressions for the reverse chlorination processes have been calculated to be k(Cl + C6H6 -* C6H5C1 + ) = (4.7 x 10*°) exp(-13453/7) L/(mol-s), k(Cl + C6H5C1 -» o-C6H4C12 + ) = (2.9 X 1010) exp(-15075/7') L/(mol-s), and k(Cl + C6H5C1p-C6H4Cl2 + ) = (8.8 X 109) exp(-13614/7) L/mol-s.

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JP-10 (exo-tetrahydrodicyclopentadiene, C10H16) ignition delay times were measured in a preheated shock tube. The vapor pressures of the JP-10 were measured directly by using a high-precision vacuum gauge, to remedy the difficulty in determining the gaseous concentrations of heavy hydrocarbon fuel arising from the adsorption on the wall in shock tube experiments. The whole variation of pressure and emission of the OH or CH radicals were observed in the ignition process by a pressure transducer and a photomultiplier with a monochromator. The emission of the OH or CH radicals was used to identify the time to ignition. Experiments were performed over the pressure range of 151-556 kPa, temperature range of 1000-2100 K, fuel concentrations of 0.1%-0.55% mole fraction, and stoichiometric ratios of 0.25, 0.5, 1.0 and 2.0. The experimental results show that for the lower and higher temperature ranges, there are different dependency relationships of the ignition time on the temperature and the concentrations of JP-10 and oxygen.