| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a mass spectrometer which can analyze in high sensitivity the sample separated by a gas chromatography (GC). <P>SOLUTION: The mass spectrometer comprises an atmospheric pressure chemical ion source which is equipped with (a1) a first ionizing part which is provided with a needle electrode and an exhaust opening of a primary ion forming gas and forms a primary ion from the primary ion forming gas by discharge of the needle electrode, (a2) a primary ion inlet pore where the primary ion passes through, and (a3) a second ionizing part which is provided with an inlet opening of the primary ion forming gas, and by reaction of the primary ion and a sample gas introduced from the terminal of the column of the GC, forms the sample ion and the terminal of the column is arranged inside, (b) a sample ion movement pore, and (c) a mass spectrometer for carrying out mass spectrometry of the sample ion. When the primary ion forming gas passes through the primary ion inlet pore and is flowed from the top end of the needle electrode to the exhaust opening, and the radius of the primary ion inlet pore is made R and the distance from the axis for connecting the primary ion inlet pore and the sample gas movement pore to the terminal of the column is made r, the terminal of the column is arranged at a position to satisfy r≤2R. Thereby, the mass spectrometer is not affected by contamination and dilution of the sample gas. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
