Andersen Christina, Nielsen Ole John, Østerstrøm Freja F, Ausmeel Stina, Nilsson Elna J K, Sulbaek Andersen Mads P
Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark.
Combustion Physics, Lund University , Professorgatan 1 SE-221 00, Lund, Sweden.
J Phys Chem A. 2016 Sep 22;120(37):7320-6. doi: 10.1021/acs.jpca.6b06618. Epub 2016 Sep 7.
FTIR smog chamber techniques were used to study the kinetics of the gas-phase reactions of Cl atoms, OD radicals, and O3 with the five-membered ring-structured compounds tetrahydrofuran (C4H8O, THF), 2-methyltetrahydrofuran (CH3C4H7O, 2-MTHF), 2,5-dimethyltetrahydrofuran ((CH3)2C4H5O, 2,5-DMTHF), and furan (C4H4O). The rate coefficients determined using relative rate methods were kTHF+Cl = (1.96 ± 0.24) × 10(-10), kTHF+OD = (1.81 ± 0.27) × 10(-11), kTHF+O3 = (6.41 ± 2.90) × 10(-21), k2-MTHF+Cl = (2.65 ± 0.43) × 10(-10), k2-MTHF+OD = (2.41 ± 0.51) × 10(-11), k2-MTHF+O3 = (1.87 ± 0.82) × 10(-20), k2,5-DMTHF+OD = (4.56 ± 0.68) × 10(-11), k2,5-DMTHF+Cl = (2.84 ± 0.34) × 10(-10), k2,5-DMTHF+O3 = (4.58 ± 2.18), kfuran+Cl = (2.39 ± 0.27) × 10(-10), and kfuran+O3 = (2.60 ± 0.31) × 10(-18) molecules cm(-3) s(-1). Rate coefficients of the reactions with ozone were also determined using the absolute rate method under pseudo-first-order conditions. OD radicals, in place of OH radicals, were produced from CD3ONO to avoid spectral overlap of isopropyl and methyl nitrite with the reactants. The kinetics of OD radical reactions are expected to resemble the kinetics of OH radical reactions, and the rate coefficients of the reactions with OD radicals were used to calculate the atmospheric lifetimes with respect to reactions with OH radicals. The lifetimes of THF, 2-MTHF, and 2,5-DMTHF are approximately 15, 12, and 6 h, respectively.
傅里叶变换红外光谱烟雾箱技术被用于研究氯原子、OD自由基和臭氧与五元环结构化合物四氢呋喃（C4H8O，THF）、2-甲基四氢呋喃（CH3C4H7O，2-MTHF）、2,5-二甲基四氢呋喃（(CH3)2C4H5O，2,5-DMTHF）和呋喃（C4H4O）的气相反应动力学。使用相对速率法测定的速率系数为：kTHF+Cl = (1.96 ± 0.24) × 10(-10)，kTHF+OD = (1.81 ± 0.27) × 10(-11)，kTHF+O3 = (6.41 ± 2.90) × 10(-21)，k2-MTHF+Cl = (2.65 ± 0.43) × 10(-10)，k2-MTHF+OD = (2.41 ± 0.51) × 10(-11)，k2-MTHF+O3 = (1.87 ± 0.82) × 10(-20)，k2,5-DMTHF+OD = (4.56 ± 0.68) × 10(-11)，k2,5-DMTHF+Cl = (2.84 ± 0.34) × 10(-10)，k2,5-DMTHF+O3 = (4.58 ± 2.18)，kfuran+Cl = (2.39 ± 0.27) × 10(-10)，以及kfuran+O3 = (2.60 ± 0.31) × 10(-18) 分子·厘米(-3)·秒(-1)。在准一级条件下，还使用绝对速率法测定了与臭氧反应的速率系数。用CD3ONO产生OD自由基来替代OH自由基，以避免亚硝酸异丙酯和亚硝酸甲酯与反应物的光谱重叠。预计OD自由基反应的动力学与OH自由基反应的动力学相似，与OD自由基反应的速率系数被用于计算相对于与OH自由基反应的大气寿命。THF、2-MTHF和2,5-DMTHF的寿命分别约为15、12和6小时。
