摘要
OH与HO2自由基是大气中重要的氧化剂,研究它们的化学反应性质及对其进行实地测量,对深入理解大气氧化过程和了解区域乃至全球大气自净能力有重要意义。自工业革命以来,每年有数千万吨的自然和人为污染物进入对流层,这些物质会严重影响·OH的生成和消除,因此·OH的浓度可能在全球范围内发生大的变化。本文总结了国内外近年来有关·OH与HO2·的最新研究成果,目前比较一致的结论是由于人类活动的影响,全球·OH的浓度比工业革命前降低了。但是在一些污染地区,由于氮氧化合物对·OH的负反馈作用,一定程度上弥补了·OH的净损失。在最近20年中,·OH在对流层中的浓度基本稳定在106cm-3。本文还介绍了实验室研究方法及外场测量技术的进展,提出了尚待解决的一些问题。
The hydrogen radicals, · OH and HO2·, are important oxidants in the atmosphere. Consequently, studying their chemical properties and carrying out the field measurements are significant to understand the atmospheric chemical processes and even the self-cleansing capacity of the global troposphere. This paper reviewed the progress made, in recent years, on ·OH and HO2·, which suggested that the global mean · OH concentration was deceased from pre-industrial time to today due to the release of natural and anthropogenic gases each year, meanwhile, depletion of · OH by reactive carbon gases have been compensated by increased · OH formation by nitrogen oxides, the mean · OH concentration was maintained at 106cm^-3 in the near twenty years. The latest progress in laboratofial techniques and field measurements was summarized, and some research trends in the future were provided.
出处
《化学通报》
CAS
CSCD
北大核心
2005年第10期736-744,735,共10页
Chemistry
基金
国家自然科学基金资助项目(D0524011)
