Irradiation of pyrimidine in pure H2O ice with high-energy ultraviolet photons

Please use this identifier to cite or link to this item: https://ir.lib.ncu.edu.tw/handle/987654321/105108

Title:	Irradiation of pyrimidine in pure H2O ice with high-energy ultraviolet photons
Authors:	朱慶琪;Nuevo, Michel;Chen, Yu-Jung;Hu, Wei-Jie;Qiu, Jun-Ming;Wu, Shang-Ruei;Fung, Hok-Sum;Chu, Ching-Chi;Yih, Tai-Sone;Ip, Wing-Huen;Wu, C.-Y. Robert
Contributors:	理學院物理學系
Keywords:	Chromatography, High Pressure Liquid;Gas Chromatography-Mass Spectrometry;Half-Life;Ice;Photons;Pyrimidines - radiation effects;Spectrophotometry, Infrared;Synchrotrons;Ultraviolet Rays
Date:	2014-02-01
Issue Date:	2026-04-23 12:07:27 (UTC+8)
Publisher:	Mary Ann Liebert Inc.;Los Angeles, CA: SAGE Publications
Abstract:	摘要： The detection of nucleobases, the informational subunits of DNA and RNA, in several meteorites suggests that these compounds of biological interest were formed via astrophysical, abiotic processes. This hypothesis is in agreement with recent laboratory studies of irradiation of pyrimidine in H2O-rich ices with vacuum UV photons emitted by an H2-discharge lamp in the 6.9–11.3 eV (110–180 nm) range at low temperature, shown to lead to the abiotic formation of several compounds including the nucleobases uracil, cytosine, and thymine. In this work, we irradiated H2O:pyrimidine ice mixtures under astrophysically relevant conditions (14 K, ≤10−9 torr) with high-energy UV photons provided by a synchrotron source in three different ranges: the 0th order light (4.1–49.6 eV, 25–300 nm), the He i line (21.2 eV, 58.4 nm), and the He ii line (40.8 eV, 30.4 nm). The photodestruction of pyrimidine was monitored with IR spectroscopy, and the samples recovered at room temperature were analyzed with liquid and gas chromatographies. Uracil and its precursor 4(3H)-pyrimidone were found in all samples, with absolute and relative abundances varying significantly from one sample to another. These results support a scenario in which compounds of biological interest can be formed and survive in environments subjected to high-energy UV radiation fields. Key Words: Pyrimidine—Nucleobases—Interstellar ices—Cometary ices—High-energy photons—Molecular processes—Prebiotic chemistry. Astrobiology 14, 119–131. 其他題名： Astrobiology 出版者： Los Angeles, CA: SAGE Publications 出版日期： 2014-02 出處： Astrobiology, 2014-02, Vol.14 (2), p.119-131 版權： Copyright 2014, Mary Ann Liebert, Inc. 版權： Copyright 2014, Mary Ann Liebert, Inc. 2014 識別號： ISSN: 1531-1074 識別號： ISSN: 1557-8070 識別號： EISSN: 1557-8070 識別號： DOI: 10.1089/ast.2013.1093 識別號： PMID: 24512484
Appears in Collections:	[Department of Physics] journal & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	22	View/Open

社群 sharing

Loading...