| 摘要 |
<p>An apparatus and a method for standardizing a gas measuring device has a source capable of emitting a beam of radiation aligned to impinge a detector and gas particles. A hollow, open-ended tube is used as a standardization means and is placed adjacent to the beam. The tube can be moved to enclose the beam, to prevent the gas from intercepting the beam, and to transmit substantially all of the radiation from the source to the detector.</p> |
