自二十世紀以來，科學家藉著天文觀測技術的進步希望能從太空 中尋找出與地球生命起源相關的脈絡。除了天文觀測外，如今在實驗 室中模擬外太空的環境也已可行，透過實驗室中的模擬太空中極端的 化學反應已成為目前瞭解地外化學環境的研究風潮。本論文主要的目 的是希望瞭解如何透過光激發一些簡單的無機分子混合冰來形成CN化 學鍵的鍵結生成，此為生成氨基酸前必要的化學鍵結。我們在低溫下 製備了一系列不同濃度CH4和NH3的混合冰晶，利用真空紫外光及極 紫外光照射這些不同比例混合的冰晶樣品並且透過測量其紅外光譜及 質譜的變化而有系統的研究CN−及CH3NH2的生成機制。我們亦將實 驗結果與Kim和Kaiser(2011)[1]之前以5000 eV的電子照射結果做比對 討論光激發與電子輻射激發機制的不同。我們的實驗結果除了可以用 來模擬冥衛一(Charon)表面的化學反應外也提供了在冥衛一的經過冬 季後偵測CN−的可能性。人們對於外太空的好奇與探索正如我們的宇 宙一樣永無止境。

We never stop the exploration of the outer space. Since 1900s, as- tronomers have observed all over the sky to seek origin of life. Apart from observing stars, we may simulate the outer space environments and make some simple molecules in laboratories on the earth now. To investigate the formation of CN−, we deposite CH4 and NH3 (mechanism proposed by Kim and Kaiser (2011)[1]) to simulate the surface of Charon. We provide VUV and EUV irradiations as energy sources and mainly use Fourier Transform Infrared Spectrometer (FTIR) and Quadrupole Mass Spectrometer (QMS) to study different concentrations of CH4 to NH3 ice mixtures.

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