秋季黄渤海C2~C5非甲烷烃海-气通量与大气反应活性

分别运用吹扫捕集和三级低温预浓缩系统与气-质联用的方法，测定了2014年11月黄渤海表层海水和大气中主要的C₂~C₅非甲烷烃（NMHCs）的浓度，研究其分布特征及海-气通量，并评价了它们的大气化学反应活性.海水中乙烷、丙烷、异丁烷、正丁烷、乙烯、丙烯、1-丁烯、异丁烯和异戊二烯的浓度平均值分别为53.0，49.4，26.4，29.2，186，62.7，35.6，89.9，42.4pmol/L.大气中乙烷、丙烷、异丁烷、正丁烷、乙烯、丙烯、1-丁烯、异丁烯和异戊二烯的体积分数平均值分别为0.043，21，0.36，6.7，7.5，0.71，0.12，0.16，0.085×10^-9.大气中乙烷、丙烷、异丁烷、正丁烷、乙烯、丙烯、1-丁烯和异丁烯具有较好的相关性，均与异戊二烯没有相关性.海-气通量的计算结果表明，近岸陆架海域可能是大气中C₂~C₅NMHCs重要的源.通过计算C₂~C₅NMHCs的臭氧生成潜势和OH·消耗速率，表明乙烯、丙烯、丙烷和正丁烷是黄渤海大气C₂~C₅NMHCs的关键活性组分.

Sea-air fluxes and atmospheric chemical reactivity of C2~C5 non-methane hydrocarbon in the Yellow Sea and the Bohai Sea during autumn

Seawater and atmospheric concentrations of C₂~C₅ non-methane hydrocarbons (NMHCs) were determined in the Yellow Sea and Bohai Sea during November 2014 with the preconcentration methods of purge-and-trap system and three-stage low-temperature preconcentration system combined with gas chromatography with mass spectrum detector. The sea-air fluxes of NMHCs and their atmospheric chemical reactivity were also studied. The average concentrations of ethane, propane, isobutane, n-butane, ethylene, propylene, 1-butene, isobutylene and isoprene in the surface water were 53.0, 49.4, 26.4, 29.2, 186, 62.7, 35.6, 89.9 and 42.4pmol/L, respectively, and the average volume percentages in the atmosphere were 0.043, 21, 0.36, 6.7, 7.5, 0.71, 0.12, 0.16 and 0.085×10^-9. Atmospheric concentrations of ethane, propane, isobutane, n-butane, ethylene, propylene, 1-butene and isobutylene exhibited strong correlations within each other in the atmosphere, and none of them correlated to isoprene. The study shows that the coast shelf seas of China might be an important sources of C₂~C₅ NMHCs. Through the calculation of the ozone generation potential and OH· potential consumption rate of NMHCs, ethylene, propylene, propane and n-butane were found to be the key active components of C₂~C₅ NMHCs in the atmosphere over the Yellow Sea and the Bohai Sea.