Reaction of methyl radicals with hydroperoxy radicals, CH3 + HO2 → products (1) was studied using pulsed laser photolysis coupled to transient UV-vis absorption spectroscopy at 295 K and 1 bar (He). Photolysis of N2O/H2O2/CH4/H2O/He mixtures at 193.3 nm (ArF excimer laser) was used to simultaneously produce methyl radicals and hydroperoxy radicals in reactions of electronically excited oxygen atoms O((1)D) with CH4 and OH radicals with H2O2, respectively. Temporal profiles of CH3 and HO2 were recorded via absorption at 216.4 and 224 nm. The absolute intensity of the photolysis light inside the reactor was determined by an accurate in situ actinometry based on the ozone formation in the presence of molecular oxygen. The measured rate constant of reaction 1 is k1 = (3.7 ± 1.8 × 10(-11) cm(3) molecule(-1) s(-1) (295 K, 1 bar, He).
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J Phys Chem A
January 2025
National Key Laboratory of Solid Propulsion, School of Astronautics, Northwestern Polytechnical University, Xi'an 710072, China.
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July 2024
MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Beijing University of Technology, Beijing 100124, China.
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December 2023
National Key Laboratory of Solid Rocket Propulsion, School of Astronautics, Northwestern Polytechnical University, Xi'an 710072, China.
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December 2023
Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States.
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August 2023
Ningbo University of Technology, Ningbo, Zhejiang 315211, China.
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