Aix Marseille Univ, CNRS, LCE, Marseille, France; Institut de Radioprotection et de Sûreté Nucléaire, PSN-RES/SAG/LETR, Cadarache, France.
Aix Marseille Univ, CNRS, LCE, Marseille, France.
Sci Total Environ. 2020 Jun 25;723:137951. doi: 10.1016/j.scitotenv.2020.137951. Epub 2020 Mar 14.
A molecular derivatization method followed by gas chromatographic separation coupled with mass spectrometric detection was used to study photolytic degradation of I adsorbed on solid SiO particles. This heterogeneous photodegradation of I is studied at ambient temperature in synthetic air to better understand I atmospheric dispersion and environmental fate. The obtained laboratory results show a considerably enhanced atmospheric lifetime of molecular iodine adsorbed on solid media. The heterogeneous atmospheric residence time (τ) of I is calculated to be τ ≈ 187 min, i.e., τ ≈ 3 h. The obtained heterogeneous lifetime of I is shown to be considerably longer than its destruction by its principal atmospheric sink, namely, photolysis. The observed enhanced atmospheric lifetime of I on heterogeneous media will likely have direct consequences on the atmospheric transport of I that influences the toxicity or the oxidative capacity of the atmosphere.
采用分子衍生化方法结合气相色谱分离和质谱检测，研究了吸附在固体 SiO 颗粒上的 I 的光降解。在模拟空气中，在环境温度下研究了这种异相光降解，以更好地了解 I 在大气中的分散和环境归宿。得到的实验室结果表明，吸附在固体介质上的分子碘的大气寿命大大延长。计算得到 I 的非均相大气停留时间（τ）为 τ≈187min，即 τ≈3h。结果表明，I 在非均相介质中的非均相寿命比其主要大气汇（即光解）的破坏时间长得多。在异相介质中观察到的 I 的大气寿命延长，很可能会直接影响 I 的大气传输，从而影响大气的毒性或氧化能力。
