Abstract: The experimental simulation was employed to study the atmospheric chemistry of isoprene with OH radicals in the presence of NO_x, using long-path Fourier transform infrared (LP-FTIR) method. OH radical was produced from photodissociation of CH₃ONO under irradiation of black lights. Results showed that carbonyl compounds, organic nitrates, HCOOH and CO, were formed. Methacrolein (CH₂=C(CH₃)CHO), methyl vinyl ketone (CH₃C(O)CH=CH₂) and HCHO were identified. At the temperature of 298K and the pressure of 93.3kPa, yields of methacrolein and methyl vinyl ketone were (20.8±1.5)% and (33.4±2.2)% respectively. The pressure variation did not influence their yields. Finally the reaction of isoprene with OH radical in the presence of NO_x was discussed briefly.

Key words: isoprene, OH radical, atmospheric chemical reaction

摘要： 采用长光路傅立叶变换红外光谱(LP-FTIR)技术，研究NO_x存在下异戊二烯与氢氧自由基(OH)的模拟大气化学反应。OH自由基由亚硝酸甲脂(CH_３ONO)黑光灯光解产生。结果表明，产物中主要有羰基化合物、硝酸酯或过氧硝酸酯、甲酸(HCOOH)及CO等。鉴定出的羰基化合物为甲基丙烯醛(CH_２=C(CH₃)CHO)、甲基乙烯基酮(CH_３Ｃ(O)CH=ＣＨ_２)和甲醛(HCHO)。在298K、93.3kPa时，甲基丙烯醛和甲基乙烯基酮的产率分别为(20.8±1.5)%和(33.4±2.2)%。压力变化对这两种羰基化合物的产率几乎无影响。最后对NO_x存在下的异戊二烯/OH自由基反应进行了简略讨论。

关键词: 异戊二烯, OH自由基, 大气化学反应