跳到主要內容

簡易檢索 / 詳目顯示

回結果列表
研究生： 謝智明
Jhi-Ming Sheh
論文名稱： 16K下H2O+CO2+NH3混合冰晶的光脫附反應之傅氏紅外光譜
FTIR spectra of EUV Photo-desorbed H2O+CO2+NH3 Mixed Ice System at
指導教授： 易台生
Tai-Sone Yih
口試委員:
學位類別： 碩士
Master
系所名稱： 理學院 - 物理學系
Department of Physics
畢業學年度： 91
語文別： 英文
論文頁數： 30
中文關鍵詞： 傅氏紅外光譜儀 、冷凍機 、水 、二氧化碳 、甲烷 、乙烷 、甲醛
外文關鍵詞： C2H6, CH4, H2CO3, H2CO, XCN, NH3, CO2, H2O, cryostat, mixed ice, FTIR
相關次數： 點閱：19  下載：0 
分享至:
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報

    • 我們使用傅氏紅外光譜儀測量混合冰晶，水，二氧化碳，氨在超高真空，低溫16K下使用在新竹同步輻射中心的真空紫外光之光譜，其生成物含有XCN, CO, CH3OH, C2H6, CH3, H2CO, H2CO3, and possibly HCOOH, CH4 及 CO3 等等，但未含乙醇及丙烷。

    Abstract
    Experimental results on the spectral identification of new infrared absorption features and the changes of their absorbances produced through vacuum ultraviolet-extreme ultraviolet(VUV-EUV) photon-induced chemical reactions in the H2O-NH3-CO2 mixed ices at 16K are obtained. The compositions, i.e., H2O:NH3:CO2= 6:1:1 were chosen in this work. Zeroth order white light from the SEYA beamline at Synchrotron Radiation Research Center (SRRC) in Hsinchu was used to provide required VUV-EUV photons. A FTIR spectrometer was employed to obtain the in-situ IR spectra produced through VUV or EVU photolysis of a given ice sample. Ultraviolet photolysis of these ices produces a variety of photoproducts including XCN, CO, CH3OH, C2H6, CH3, H2CO, H2CO3, and possibly HCOOH, CH4 and CO3. However, despite of so many photoproducts were produced by the feeding of strong white light photon energies C2H5OH and C3H8 were still not been found in these experiments.

    Abstract……………………………………………………………………..Ⅱ Contents………………….……..…………………………..………………….Ⅲ Figures List…………………….……………………………………………..Ⅳ Tables List…………………………………………………………………….Ⅴ Chapter Ⅰ Introduction…………………………………………..1 Chapter Ⅱ Experimental Set-up and Procedures…………………………3 Chapter Ⅲ Results & Discussion…………………………………………5 Chapter Ⅳ Conclusion……………………………………………………10 References…………………………………..………………………...…………11 Appendix A: Photon Flux & Quantum Efficiency……………………………28 Appendix B: Column Density & Energy Dose………………………………..29 Appendix C: Summary of the IR spectral positions and their band strengths for the relevant icy molecules………………………………….30 Figures Lists Fig. 1 A schematic diagram of the preparation system………….……..…………14 Fig. 2 A schematic diagram of the ultra-high vacuum chamber………………….15 Fig. 3 The photo of the experiment arrangement…………………………………16 Fig. 4-1 The IR absorbance of the mixed ice sample before photolysis……………..17 Fig. 4-2The IR absorbance of the mixed ice sample that the difference of absorbances ( continuous to next two pages ) of H2O + CO2 + NH3 ( 6:1:1 ) ices taken after the white light irradiation. We have found new products such as CH3OH, C2H6, CO3, H2CO, H2CO3, CH3, HCOOH…………………….……………18 Fig. 4-3 The IR absorbance of the mixed ice sample that the difference of absorbances (continuous to next pages ) of H2O + CO2 + NH3 ( 6:1:1 ) ices taken after the white light irradiation. We have found new products such as CH3OH, C2H6, CO3, H2CO, H2CO3, CH3, HCOOH……………………………………...…19 Fig. 4-4 The IR absorbance of the mixed ice sample that the difference of absorbances of H2O + CO2 + NH3 ( 6:1:1 ) ices taken after the white light irradiation. We have found new products such as CH3OH, C2H6, CO3, H2CO, H2CO3, CH3, HCOOH……………………………………………………………….……20 Fig. 5 The IR absorbance of the mixed ice sample before photolysis ( the left top panel ) and the difference of absorbances of evolution of H2O + CO2 + NH3 ( 6:1:1 ) ices taken after the white light irradiation. We have found new products such as XCN, CO…………………………………………………21 Fig. 6-1 Plot of results for R.G.A. with mass=1, 2, 15, 16, 17, 18, 19, 28, 29, 30, 32, 40, 44, 45 amu…………………………………………………………...…22 Fig. 6-2 Plot of results for R.G.A. with mass=41, 100 amu……………..………..…23 Fig. 7-1 Plot of results for the H2CO3 and CO product column densities as a function of the total incident photon energy in units of eV/cm2……………...……...24 Fig. 7-2Plot of results for the H2CO and CH3OH product column densities as a function of the total incident photon energy in units of eV/cm2……..…,.....25 Fig. 7-3 Plot of results for the C2H4, C2H6 and XCN product column densities as a function of the total incident photon energy in units of eV/cm2……….…...26 Fig. 8 The plot of Ni mesh quantum efficinecy for Seya beamline at SRRC……...28 Fig. 9 The plot of Photon Flux for Seya beamline at SRRC……………………….28 Tables List Table 1 The results of H2CO3, H2CO, CO, CH3OH, C2H4, C2H6 and XCN that column density vs. energy dose…………………………………………………...…27 Table 2 Summary of the IR spectral positions and their band strengths for the relevant icy molecules………………………………………………………………..30

    Wu C. Y. R., D. L. Judge, B. M. Cheng, W. H. Shih, T. S. Yih and W. H. Ip, 2002a, Extreme Ultraviolet Photon-Induced Chemical Reactions in the C2H2-H2O Mixed Ices at 10 K, Icarus 156, pp. 456-473.
    Wu C. Y. R., D. L. Judge and B. M. Cheng, 2002b, EUV Photolysis of CH4 +H2O Mixed Ice Systems at 10K, Bull. Am. Astron. Soc., 34, No. 3, pp. 908.
    Bernstein M. P., S. A. Sandford and L. J. Allamandola, 2000, H, C, N, and O Isotopic Substitution Studies of the 2165 Wavenumber (4.62 Micron) “XCN” Feature Produced by Ultraviolet Photolysis of Mixed Molecular Ices, APJ., 542, pp. 894-897.
    Bernstein, M., S. A. Sandford, and L. J. Allamandola, 1999, Life’s Far-Flung Raw Materials, Scientific American, p. 26, the July issue.
    Dalton, J. B., T. L. Roush, and C. S. Jamieson, Studies of Planetary Materials Using Cryogenic Reflectance Spectroscopy, Bull. Am. Astron. Soc., 34, No. 3,912(abstr.).
    D’Hendecourt, L. B., L. J. Allamandola, R. J. A. Grim, and J. M. Greenberg, 1986, Time-Dependent Chemistry in Dense Molecular Clouds, II. Ultraviolet Photoprocessing and Infrared Spectroscopy of Grain Mantles, Astron. Astrophys., 158, pp. 119-134.
    D’Hendecourt, L. B., L. J. Allamandola, 1986, Time-Dependent Chemistry in Dense Molecular Clouds, III. Infrared Band Cross Section of Molecules in the Solid State at 10 K, Astron. Astrophys. Suppl. Ser., 64, 453-467.
    Ehrenfreund P. and S. B. Charnley, 2000, Organic Molecules in the Interstellar Medium, Comets, and Meteorites: A Voyage from Dark Clouds to the Early Earth, Annu. Rev. Astron. Astrophys. VOL. 38, pp.427-483.
    Elsila J., L. J. Allamandola and S. A. Sandford, 1997, The 2140 cm-1(4.673 Microns ) Solid CO Band :The Case for Interstellar O2 and N2 and The Photochemistry of Nonpolar Interstellar Ice Analogs, APJ.,479, pp. 818-838.
    Gerakines P. A., M. H. Moore, and R. L. Hudson, 2000, Carbonic Acid Production in the H2O:CO2 Ices. UV Photolysis vs. Proton Bombardment, Astron. Astrophys., 357, 793-800.
    Gerakines P. A. and M. H. Moore, 2001, Energetic Processing of Laboratory Ice Analogs: UV Photolysis versus Ion Bombardment, J. Geophys. Res., VOL. 106, pp. 33,381-33,385.
    Greeley R., S. Heiner, J. E. Klemaszewski, 2001, Infrared Spectra of Proton Irradiated Ices Containing Methanol, J. Geophys. Res. Planets, 106, pp. 32610
    Gerakines P. A., W. A. Schutte, J. M. Greenberg, and E. F. van Dishoeck, 1995, The Infrared Band Strengths of H2O, CO and CO2 in Laboratory Simulations of Astrophysical Ice Mixtures, Astron. Astrophys, 296, pp. 810-818.
    Gerakines, P. A., M. H. Moore, and R. L. Hudson, 2000, Carbonic Acid Production In H2O:CO2 Ices UV Photolysis Vs. Proton Bombardment, Astron. Astrophys., 357, pp. 793-800.
    Gerakines, P. A., M. H. Moore, and R. L. Hudson, 2001, Energetic Processing of Laboratory Ice Analogs:UV Photolysis Versus Ion Bombardment, J. Geophys. Res., VOL. 106, No. E12, pp. 33,381-33,385.
    Hagen, W., A. G. G. M. Tielens, and J. M. Greenberg, 1983, A Laboratory Study of the Infrared Spectra of Interstellar Ices, Astron. Astrophys. Supp. Ser., 51, pp. 389-416.
    Hudson R. L. and Moore M. H.,1992, A Far-IR Study of Irradiated Amorphous Ice: An Unreported Oscillation Between Amorphous and Crystalline Phases, J. Phys. Chem., 96, pp. 6500-6504.
    Hudson R. L. and M. H. Moore, 1995, Far-IR Spectral Changes Accompanying Proton Irradiation of Solids of Astrochemical Interest, Radiat. Phys. Chem. VOL. 45, No. 5, pp. 779-789.
    Hudson R. L. and M. H. Moore, 1995, Note : Hydrocarbon Radiation Chemistry In Ices of Cometary Relevance, Icarus, 126, pp. 233-235.
    Hudson R. L. and M. H. Moore, 2000, New Experiments and Interpretations Concerning The “XCN” Band in Interstellar Ice Analogues, Astron. Astrophys. VOL.357, pp.787-792.
    Hudson R. L. and M. H. Moore, 1999, Laboratory Studies of the Formation of Methanol and Other Organic Molecules by Water + Carbon Monoxide Radiolysis: Relevance to Comets, Icy Satellites, and Interstellar Ices, Icarus 140, pp. 451-461.
    McCord, T. B., G. B. Hansen, F. P. Fanale, R. W. Carlson, D. L. Matson, T. V. Johnson, W. D. Smythe, J. K. Crowley, P. D. Martin, A. Ocampo, C. A. Hibbitts, J. C. Granahan, and the NIMS Team, 1998, Salts on Europ’a Surface Detected by Galileo’s Near Infrared Mapping Spectrometer, Science, 280, 1242-1245.
    Morre M. H., R. Khanna, and B. Doon, 1991, Studies of Proton Irradiated H2O+CO2 and H2O+CO Ices and Analysis of Synthesized Molecules, J. Geophys. Res. Vol. 96 pp.17541-17545.
    Moore M. H. and R. L. Hudson, 1998, Infrared Study of Ion-Irradiated Wate –Ice Mixtures with Hydrocarbons Relevant to Comets, Icarus 135, pp. 518-527
    Moore M. H., R. F. Ferrante and J. A. Nuth III, 1996, Infrared Spectra of Proton Irradiated Ices Containin Methanol, Planet. Space Sci., VOL 44, No. 9, pp. 927-935
    Pendletion, Y. J. and L. J. Allamandola, 2002, The Organic Refractory Material in The Diffuse Interstellar Medium:Mid_Infrared Spectroscopic Constraints, APJ.,138, pp. 75-98.
    Pirronello, V., W. L. Brown, L. J. Lanzerotti, K. J. Marcantonio, and E. H. Simmons, 1982, Formaldehyde Formation in a H2O/CO2 Ice Mixture Under Irradiation by Fast Ions, APJ., 262, pp. 636-640.
    Sandford, S. A. and L. J. Allamandola, 1993, Condensation and Vaporization Studies of CH3OH and NH3 Ices: Major Implications for Astrochemistry, APJ., 417, pp. 815-825.

    QR CODE
    :::