• 作者： 王念夏; 李遠鵬
• 作者服務機構： 國立清華大學化學系
• 中文摘要： 吾人已建立一套可靈敏測量羥基濃度的氣流管裝置，管中之羥基濃度係由共振螢光法測得。其光源使用微波引發羥基放光，而利用干涉濾光片及光電子計量系統偵測管中羥基之螢光。此方法偵測羥基之靈敏度優於每毫升4x10 分子。 羥基與硫化氫之反應速率可利用此裝置在假一次反應狀況下（硫化氫與羥基濃度比大於20，羥基濃度低於每毫升8 x 10 分子）測得。在溫度為300 K時，量得之反應速率常數為K = (4.3 0.6) x 10 毫升/分子．秒，較以往之公認值為低。較低之速率常數表示硫化氫在大氣之存留期會較以往所認為者長一點。
• 英文摘要： A discharge flow system coupled with a sensitive OH detection method has been constructed. Theconcentration of OH radicals in the flow system was determined by the resonance fluorescence techniqueusing a microwave-discharged OH lamp as the light source and an interference filter/photon counting sys-tem for detection. The detection limit for OH is better than 4 x 10 molecule cm . The rate constant of the OH+H S reaction has been studied with this system under pseudo-first-order conditions with [H S]∕【OH]＞20 and [OH] ＜8 X10 molecule cm . The measured rate constantof K ＝(4.3 0.6）x 10 cm molecule s at 300K is lower than the previously recommended rate con-stant of 5.3x10 cm molecule s , and a slightly longer life-time for atmospheric H S is thus expected.
• 中文關鍵字： rate constant; discharge-flow; H2S (hydrogen sulfide); OH (hydroxyl)
• 英文關鍵字： --