The ethyl radical was observed in a low-pressure premixed gasoline/oxygen/argon flame by using tunable vacuum ultraviolet photoionization mass spectrometry. The ionization energy(IE) of the ethyl radical was derived to be(8.24±0.02) eV from the photoionization efficiency curve. In addition, a high-level ab initio Gaussian-3(G3) method was used to calculate the energies of the radical and its cation. The calculated adiabatic ionization potential is 8.17 eV, which is in good agreement with the experimental value.
Here we report a combustion endstation at National Synchrotron Radiation Laboratory (NSRL) and some primary experimental results. Synchrotron radiation can provide the tunable vacuum ultraviolet (VUV) photon with the high intensity and the good collimation. VUV photoioni-zation is a single-photon ionization process. Combined with molecular-beam mass spectrometry (MBMS), the VUV single-photon ionization can be applied to detect the combustion products, especially the intermediates and free radicals produced from combustion process. This method is proved to be a powerful tool for combustion study, which could be helpful for developing combustion kinetic models and understanding the mechanism of combustion reactions.
在有 stoichiometric 等价比率(=1 ) 的 2.667 kPa 的 premixed 乙烯 / 氧 / 氩火焰的全面试验性的研究与悦耳的同步加速器光电游离和分子横梁的采样团 spectrometry 技术被执行。在火焰的最观察的种类的异构体被光电游离效率系列的大小明白地识别，例如 C 3 H 4, C 2 H 4 O 和 C 4 H 4 。直到 C 7 H 8 被在电离阀值，和火焰温度侧面附近在选择光子精力扫描炉子位置测量被使用 Pt/Pt-13%Rh 热电偶获得。与以前的研究相比，很多新火焰种类： C 3 H 2, C 3 H 3, C 3 H 5, C 2 H 6 O ， C 4 H 2, C 4 H 4, C 4 H 6, C 3 H 4 O ， C 3 H 6 O ， C 3 H 8 O ， C 5 H 6, C 4 H 8 O 和 C 7 H 8,被观察。在火焰的一系列自由激进分子被检测是 CH 3, C 2 H 3, C 2 H 5, HCO， C 3 H 3 和 C 3 H 5 。基于试验性的工作，减少的反应机制包括 40 种类和 223 反应被开发。建模并且大小为主要种类和大多数中介同意很好。一个详细运动模型为这火焰被需要。
