Faust B C, Anastasio C, Allen J M, Arakaki T
Duke University, School of the Environment, Durham, NC 27708.
Science. 1993 Apr 2;260(5104):73-5. doi: 10.1126/science.8465202.
Gas-to-drop partitioning of hydrogen peroxide and its precursor, the hydroperoxyl radical (HO2.), has been considered the predominant or sole source of hydrogen peroxide in atmospheric water drops. However, atmospheric water can absorb solar ultraviolet radiation, which initiates the photoformation of peroxides (primarily hydrogen peroxide). Measurements of peroxide photoformation rates in authentic atmospheric water samples demonstrate that aqueous-phase photochemical reactions are a significant, and in some cases dominant, source of hydrogen peroxide to cloud and fog drops. This additional source could significantly change the current understanding, and hence, the models, of sulfuric acid deposition because hydrogen peroxide is the limiting reagent in the dominant pathway for the oxidation of sulfur dioxide to sulfuric acid in the troposphere over eastern North America.
过氧化氢及其前体氢过氧自由基（HO2·）在气-滴间的分配被认为是大气水滴中过氧化氢的主要或唯一来源。然而，大气水能够吸收太阳紫外线辐射，从而引发过氧化物（主要是过氧化氢）的光生成。对真实大气水样中过氧化物光生成速率的测量表明，水相光化学反应是云滴和雾滴中过氧化氢的一个重要来源，在某些情况下甚至是主要来源。这一额外来源可能会显著改变目前对硫酸沉积的理解，进而改变相关模型，因为在北美东部对流层中，二氧化硫氧化为硫酸的主要途径中，过氧化氢是限制试剂。
