| 摘要 |
<p>A miniature mass spectrometer is disclosed comprising: an atmospheric pressure ionisation source 701; a first vacuum chamber having an atmospheric pressure sampling orifice or capillary 702; a RF ion guide 703 located in a second vacuum chamber; and a mass analyser 704 and ion detector 705 located in third vacuum chamber. A RF ion guide may also be provided within the first vacuum chamber. The product of the pressure in the first vacuum chamber and the length of said chamber or said first RF ion guide is in the range 10-100 mbar-cm; and the product of the pressure in the second vacuum chamber and the length of the second RF ion guide 703 is in the range 0.05-0.3 mbar-cm, most preferably 0.17 mbar-cm..</p> |
