| 摘要 |
<p>An ion mobility spectrometer (10) for detecting gas constituents in an ambient air (95) incorporating a cylindrical tube (20) containing a reaction region (74), a shutter assembly (64) and a drift region (44) therein, the cylindrical tube (20) fits within a housing (12, 14) having a chamber or space (31) between the cylindrical tube (20) and the housing (12, 14) for heating drift gas (27) prior to entry into the drift region (44). Further, the cylindrical tube (20) may have interior annular ledges (49, 55) to facilitate positioning of the shutter assembly (64) and an aperture grid (107). The invention overcomes the problem of controlling the temperature of the drift gas (27) prior to entry into the drift region (44) to enhance the uniformity of ion drift mobility times and the problem of a mechanical assembly which is difficult to disassemble.</p> |
