2007-10-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/700139摘要：大氣中，氣體和氣膠粒子之間的非均相反應（heterogeneous reactions）在大氣化學的流程中扮演著重要角色，這些反應除了改變大氣中氣態分子的分佈外，氣膠粒子的物理性質亦隨著不同的化學反應而有所變化，進而改變氣膠粒子對人類健康及氣候的影響。因此瞭解氣體的變化和氣膠粒子的反應及其性質變化將有助於我們去估計其影響。 在此計畫，我們將使用氣膠粒子流管紅外線光譜(Aerosol flow tube infrared spectroscopy, AFT-IR)及衰減全反射紅外線光譜(attenuated total reflection infared spectroscopy, ATR-IR)來偵測有機-無機混合氣膠粒子(無機成分: 硫酸銨，有機成分: 油酸或malathion )和活性氣體（例如：臭氧(O3)，氫氧自由基(OH radical)、硝酸自由基(NO3 radical)）在近似大氣環境（不同的溼度和溫度）下的反應動力學，同時我們將使用氣相質譜儀來分析氣膠粒子反應後的成分變化，進而推測其反應機構。綜合實驗結果與計算動力學模型將幫助我們了解氣體和液體在氣體和氣膠粒子界面的擴散反應，這些動力學和化學成分變化數據將可代入模式中評估這些氧化反應對氣候及人類健康所造成的影響。 <br> Abstract: Heterogeneous atmospheric reactions between aerosol particles and gas-phase active molecules play an important role in controlling chemical processes in the atmosphere. In addition to modifying the partitioning of gas-phase species, the varied physical properties of the aerosol can cause impacts on human health by penetrating into human lung, and on climate change by scattering solar radiation back to space. The work proposed here aims to develop quantitative understanding of the mechanisms and kinetics of oxidation reactions involving inorganic-organic internally mixed aerosols (ammonium sulfate mixed with oleic acid or malathion), similar to ambient aerosols, under conditions relevant to the atmosphere in order that such processes can be accurately incorporated into numerical models of atmospheric chemical processes. This information is essential to understanding and quantifying the aging processes of atmospheric particles. The experiments will employ aerosol flow tube (AFT) and attenuated total reflectance (ATR) infrared spectroscopy (IR) methods. The product identification at both gas and aerosol phases will be determined using several mass spectrometry. Integration of experimental results with a computational kinetics model will elucidate mechanistic details such as gas and liquid diffusion, mass accommodation, and chemistry for both the gas and liquid phases, and the interface. The identification of oxidation products will also provide a complete risk assessment for parent chemical species.氣膠氣候aerosolclimate