| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a discharge ionization current detector capable of improving the measurement accuracy and measurement sensitivity by suppressing the baseline current comparing with the conventional device.SOLUTION: A sapphire or high purity alumina is used as a metallic cylindrical tube 2 that is used for causing a low frequency barrier discharge and covers the surfaces of electrodes 4, 5, and 6 for plasma generation. In the low frequency barrier discharge, H or O derived from the OH contained in a dielectric substance is discharged into plasma gas for a long term, and it is found that this is a main factor of the increase in baseline current. However, by using the sapphire or high purity alumina, the baseline current can be significantly decreased, and thus, S/N and detection limit can be also improved.</p> |
