中文摘要：

气相自由基能与各种气体发生快速反应,在大气化学、燃烧化学和星际化学等重要的化学过程中起着关键性的催化作用。许多实验方法（例如荧光法和吸收法）已经用于研究气相自由基反应动力学过程,并取得许多重要的成果,但这些技术局限于探测小分子自由基反应。流动管反应器和闪光光解结合光电离质谱的实验技术以其通用性、多重探测性、选择性和灵敏性等多种优势,成为研究气相自由基反应的主要实验方法。本文介绍利用高通量、高分辨、连续可调的同步辐射光电离质谱开展多种自由基反应研究所取得的一些独创性的成果。另外,该技术具有独有的时间分辨、能量分辨和异构体分辨的能力,能够广泛用于大气化学、燃烧化学和星际化学中一些重要的气相自由基（如烷氧自由基、烃类自由基等）反应宏观动力学过程的研究。

英文摘要：

Gas-phase radicals can react rapidly with various gaseous molecules, which play a vital role in catalyzing reactions in atmospheric, combustion and interstellar chemistry. A range of experimental techniques such as fluorescence and absorption spectrometry have been employed to study the reaction processes of gas-phase radicals and acquired some important results. Despite of the sufficient sensibility in the measurement of transient species, most of these techniques are limited to small radicals with small molecules, inaccessible to bigger radicals or multiplexed detection. Lately, a combination of flow reactor, flash laser photolysis and synchrotron radiation （SR） photoionization mass spectrometry （PIMS）, serves as a universal, multiplexed, selective and sensitive method, ideal for the chemical kinetics study. Pulsed photolysis laser is used to initiate radical reaction, SR vacuum ultraviolet （VUV） light source to ionize the molecules emerging from the side pinepole and mass spectrometer to detect multiple species in the reactions （ especially many-atom species）. A plenty of original works such as the studies of CN, OH and alkylperoxy radical reactions have been done using double-focusing mass spectrometer or time-of-flight mass spectrometer and identified to be in fair agreement with the previous methods. Furthermore, the extra ordinary capability of time- and energy- resolution can be widely applicable in the kinetics study of some important radicals such as alkylperoxy and aromatic radicals in atmospheric, combustion, and interstellar chemistry.