| 摘要 |
PURPOSE:To measure the concn. of the dissolved oxygen in a sample liquid with high accuracy by bubbling a carrier gas in the sample liquid to capture the dissolved oxygen in the sample liquid on the carrier gas and detecting the concn. of the oxygen in the carrier gas by using a sensor for measuring the concn. of the oxygen in the gas. CONSTITUTION:A calibration curve is formed under the specified conditions of a sample liquid temp., gaseous pressure, etc., by confirming that a correlative relation holds between the concn. of the dissolved oxygen in the sample liquid L and the standardized value of the output of a measuring instrument. The carrier gas G is supplied from a gas conduit 2 into the sample liquid L filled in a storage tank 1 and the oxygen in the sample liquid L is removed by bubbling under the same conditions as for the conditions of forming the calibration curve. The gaseous mixture composed of the gas G and the removed oxygen rises in the sample liquid L and is captured by a capturing hood 3; thereafter, the concn. of the oxygen is measured by the sensor 4 for measuring the concn. of the oxygen in the gas. The output of the measured value is detected by a detector 5 using the calibration curve formed from the standardized value. The concn. of the dissolved oxygen in the sample liquid is thus measured with high accuracy. |
