A New Gas Chromatography Mass Spectrometer Equipped with a Hyperthermal Surface Ionization as a Ion Source

配备高温表面电离作为离子源的新型气相色谱质谱仪

• 批准号: 09554052
• 负责人: KISHI Hiroshi
• 金额: $ 6.66万
• 依托单位: Oyama National College of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09554052/
• 关键词: Surface Ionization; Aerodynamical Acceleration of Molecules; GC; MS; Kinetic Energy; Detector; イオン化エネルギー; 内部エネルギー; エネルギー変換; 正・負イオン; 質量分析

A new gas chromatography-mass spectrometer system equipped with a hyperthermal surface ionization (HSI) system as an ion source is described. The HSI is a combination of molecular acceleration in supersonic molecular beam (SMB) and surface ionization (SI). To examine the effect of various parameters on operational characteristics of this system, ionization mechanism of HSI was studied.In the article No.1, we defined the "γ-factor" as the fraction of the kinetic energy used for ionization, and was estimated from two unique Ek and Ts correlation with measured ion current, where, Ek is the molecular kinetic energy and Ts is the surface temperature. The γ values estimated from the two independent methods agreed fairly well. Deduced conclusions are : (1) the kinetic energy is partially used for ionization, (2) the efficiency of energy conversion (γ value) varies from molecule to molecule, (3) the energy required for surface ionization is associated with the energy gap due to the difference in ionization energy (IE) and the surface work function (ψ).In the article No.2, a method to estimate the conversion rate of the molecular kinetic energy used for the excitation of the vibrational degrees in the molecule is described. The experimental results obtained by this method led to the following conclusions : (1) The kinetic energy is partially used for excitation of the vibrational degree, and the conversion rate amount to some 30 %. (2) The total rate amounts to some 50 % of the initial kinetic energy converted to the internal energy of the molecule. (3) There is only a very small probability of surface thermal energy being transferred to the internal energy of the molecule.The article No.3 summarizes the recent development in surface ionization (SI) of organics. This includes (1) basic principles, (2) instrumentation, (3) response characteristics, and (4) applications.

介绍了一种以高温表面电离(HSI)系统为离子源的新型气相色谱-质谱仪系统。HSI是超声分子束(SMB)中的分子加速和表面电离(SI)的结合。为了考察各种参数对该系统运行特性的影响，研究了高能半导体的电离机理。在第一篇文章中，我们定义了“γ因子”为电离动能的比例，并根据两个唯一的Ek和Ts与被测离子流的关联式进行估算，其中Ek是分子动能，Ts是表面温度。两种独立方法估算的γ值吻合较好。推导的结论是：(1)动能部分用于电离，(2)能量转换效率(γ值)因分子而异，(3)表面电离所需的能量与由于电离能(IE)和表面功函数(ψ)的差异而产生的能隙有关。在第二篇文章中，描述了一种估算用于激发分子振动度的分子动能转化率的方法。实验结果表明：(1)动能部分用于振动度的激发，转化率达30%左右。(2)总速率相当于将初始动能转换为分子内能的约50%。(3)表面热能转移到分子内能的可能性很小。文献3综述了有机物表面电离的最新进展。这包括(1)基本原理、(2)仪器、(3)响应特性和(4)应用。

项目成果

Hiroshi Kishi, Hiromi Arimoto and Toshihiro Fujii: "Internal energy deposition through collision of hyperthermal neutral molecules with energies up to 5 eV with a surface"International Journal of Mass Spectrometry. Vol. 194. 75-83 (2000)

Hiroshi Kishi、Hiromi Arimoto 和 Toshihiro Fujii：“通过能量高达 5 eV 的超高温中性分子与表面碰撞实现内部能量沉积”国际质谱杂志。

Hiroshi Kishi and Toshihiro Fujii ;: "Internal energy deposition through collision of hyperthermal neutral molecules with energies up to 5 eV with a surface ;"International Journal of Mass Spectrometry ;. Vol194. 75-83 (2000)

Hiroshi Kishi 和 Toshihiro Fujii；：“通过能量高达 5 eV 的超高温中性分子与表面碰撞实现内部能量沉积；”国际质谱杂志；。

Hiroshi Kishi and Toshihiro Fujii: "Organic gas/surface interaction:Fraction(γ value)of the kinetic energy used for ionization" Journal of the Chemical Physics. Vol.108 No.5. 1940-1943 (1998)

Hiroshi Kishi 和 Toshihiro Fujii：“有机气体/表面相互作用：用于电离的动能的分数（γ 值）”化学物理杂志第 108 卷第 5 期（1940-1943）。

Hiroshi Kishi and Toshihiro Fujii ;: "Organic gas/surface interaction : Fraction(γ value) of the kinetic enrgy used for ionization ;"The Journal of Chemical Physics ;. Vol108, No. 5 ;. 1940-1943 (1998)

Hiroshi Kishi 和 Toshihiro Fujii；：“有机气体/表面相互作用：用于电离的动能分数（γ 值）”；《化学物理学杂志》；第 108 卷，第 5 期；1940-1943 年。

Toshihiro Fujii ;: "Principles and application of surface ionization in GC-MS in "Current Practice of GC/MS""Marcel Dekker W. M. A. Niessen(ed. )(in press. ). (2000)

Toshihiro Fujii；：“GC-MS 中表面电离的原理和应用，《GC/MS 的当前实践》”Marcel Dekker W. M. A. Niessen（编辑）（出版中）。