燃燒化學中重要自由基之反應動力學研究(III)

Abstract

我們計畫研究燃燒化學中重要自由基的反應動力學。首先利用一套無膜震波管／原子 吸收光譜系統，研究在高溫下(> 1500 K) CH2 自由基與H2 及O2 之反應動力學。CH2 由 熱解CH2I2 而得，藉由偵測氫及氧原子濃度之時間變化，並與詳細之反應機制比對來 得到動力學資訊。若經費及人力許可，我們除了將利用已建立之雷射光解／雷射誘發 螢光系統NCN 自由基之製造及偵測技術，繼續研究NH + CN  NCN+ H 反應之動力 學外，將開始建立HNCN 自由基之製造及偵測技術，以便在以後年度進行其與O2, NO, NO2 等分子之反應速率常數值量測。研究所得結果將與理論計算之結果相比較，可提 供重要的動力學資料。

The reaction kinetics of 3CH2 radicals with H2 and O2 will be studied in our laboratory using a diaphragmless shock tube coupled with atomic resonance absorption spectroscopy technique at elevated temperatures ( > 1500 K). Thermal decomposition of CH2I2 will be used to generate CH2 radicals and H and/or O atom will be detected in the presence of H2 or O2. Kinetic information will be yielded by fitting the temporal profiles of the atomic species to detailed mechanisms. If time and manpower permit, a laser photolysis/laser induced fluorescence system will be used to study the reaction kinetics of NCN and HNCN radicals. The generation and detection techniques of NCN have been established, the rate coefficient of the reaction of CN + NH -> NCN + H will be determined. We will also proceed to the kinetics of the reaction of HNCN with O2. The results will be compared with that of theoretical calculations and offer valuable information.