Photochemical production of hydroxyl radical and hydroperoxides in water extracts of nascent marine aerosols produced by bursting bubbles from Sargasso seawater
Photochemical production of hydroxyl radical and hydroperoxides in water extracts of nascent marine aerosols produced by bursting bubbles from Sargasso seawater
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DOI：
10.1029/2008gl035418
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发表时间：
2008-10
影响因子：
5.2
通讯作者：
Xianliang Zhou;Andrew J. Davis;D. Kieber;W. Keene;J. Maben;H. Maring;E. Dahl;M. Izaguirre;R. Sander;L. Smoydzyn
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文献类型：
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作者：
Xianliang Zhou;Andrew J. Davis;D. Kieber;W. Keene;J. Maben;H. Maring;E. Dahl;M. Izaguirre;R. Sander;L. Smoydzyn
海洋气溶胶是由海洋表面气泡破裂产生的，相对于海水而言，其有机物（OM）含量非常丰富。这种OM在海洋气溶胶的光化学演化中的重要性，特别是作为活性氧化剂的来源，尚不清楚，但可能很重要。为了研究氧化剂的产生，新生的气溶胶产生鼓泡零空气通过流动的马尾藻海水和光化学生产的OH自由基和氢过氧化物进行了量化的水溶性气溶胶提取物暴露于太阳辐射。外推到环境条件表明，OM光解是新生气溶胶中OH（1.1 × 10−8 M s−1）和氢过氧化物（1.7 × 10−8 M s−1）的主要原位来源; NO3−光解是老化酸化气溶胶的主要来源（分别为1.4 × 10−7和4.1 × 10−8 M s−1）。原位OH光产生与气相吸收相当，而H2 O2光产生较慢。结果提供了重要的限制，海洋气溶胶中的氧化剂来源量化不良。
Marine aerosols produced by bursting bubbles at the ocean surface are highly enriched in organic matter (OM) relative to seawater. The importance of this OM in the photochemical evolution of marine aerosols, particularly as a source of reactive oxidants, is unknown but likely significant. To investigate oxidant production, nascent aerosols were generated by bubbling zero air through flowing Sargasso seawater and photochemical production of OH radical and hydroperoxide were quantified in aqueous aerosol extracts exposed to solar radiation. Extrapolation to ambient conditions indicates that OM photolysis was the primary in situ source for both OH (1.1 × 10−8 M s−1) and hydroperoxides (1.7 × 10−8 M s−1) in nascent aerosols; NO3− photolysis was the primary source in aged, acidified aerosols (1.4 × 10−7 and 4.1 × 10−8 M s−1, respectively). In situ OH photoproduction was comparable to gas‐phase uptake whereas H2O2 photoproduction was slower. Results provide important constraints for poorly quantified oxidant sources in marine aerosols.