关于聚甲基替代在大气中的OH基因降解的理论研究
Hui Zhao1, Shuangjun Wang1, Lu Chenggang1
1School of Environmental and Municipal Engineering, Qingdao University of Technology, Fushun Road 11, Qingdao, Shandong, 266033, PR China.
Chemosphere
|January 21, 2024
概括
研究了甲基 (5-PeMB) 和六甲基 (6-HeMB) 的降解机制. DFT计算显示了有利的添加途径,计算的大气寿命分别为2.17小时和2.78小时,毒性降低.
科学领域:
- 环境化学环境化学
- 大气化学 大气化学
- 计算化学的计算化学
背景情况:
- 五甲基 (5-PeMB) 和六甲基 (6-HeMB) 是石油和煤焦油中普遍存在的挥发性有机化合物 (VOC).
- 这些挥发性有机物释放到大气中,导致光化学烟雾和二次有机气溶 (SOA),对人类健康和生态系统构成风险.
研究的目的:
- 阐明OH启动的5-PeMB和6-HeMB的降解机制.
- 为了确定这些化合物的大气化学和环境影响.
主要方法:
- 用密度函数理论 (DFT) 的计算来研究反应路径.
- 计算了能量障碍和降解速率常数.
- 大气生命周期的估计是基于计算的速率常数.
- 定量结构-活性关系 (QSAR) 模型评估了与降解相关的毒性.
主要成果:
- 补充路径被确定为5-PeMB和6-HeMB最有利的降解路径,具有较低的能量障碍.
- 在298K的降解速率常数计算为2.69 × 10-10cm3分子-1s-1的5-PeMB和1.28 × 10-10cm3分子-1s-1的6-HeMB.
- 5-PeMB和6-HeMB在大气中的估计寿命分别为2.17小时和2.78小时.
- 在QSAR分析中表明,在降解过程中对水生生物 (鱼类,大,绿藻) 的毒性下降.
结论:
- OH启动的5-PeMB和6-HeMB降解主要通过添加途径进行.
- 计算的大气寿命表明大气中的降解速度相对较快.
- 降解过程导致这些化合物的环境毒性减少.
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