Title:
GAS MEASUREMENT DEVICE AND GAS MEASUREMENT METHOD
Document Type and Number:
WIPO Patent Application WO/2020/105118
Kind Code:
A1
Abstract:
According to the present invention, a gas to be measured is introduced into a measurement cell 40 so that the pressure therein becomes a prescribed pressure, and then measurement is performed at a prescribed wavenumber by means of CRDS through a laser light source unit (1), an optical switch (3), an optical resonator (4), and a light detector (5). Next, a portion of the gas to be measured in the measurement cell (40) is discharged to lower the pressure, and measurement is performed at a wavenumber of an absorption peak of 14CO2 that is a target component. Since the influence of absorption of 14CO2 is negligible at the time of measurement under a high pressure, the background concentration of 12CO2 or the like is obtained from a ring-down time. The background influence is included in absorption coefficients calculated from the ring-down time obtained from measurement data under a low pressure, but the background absorption coefficients under the low pressure can be calculated from the background concentration obtained under the high pressure. By using the calculated result, a concentration calculation unit (73) obtains the absorption coefficients of only 14CO2 from which the background influence is removed, and calculates the concentration of only 14CO2. A highly accurate absolute concentration for the target component of 14CO2 or the like can be obtained from the results of measurements performed twice under different pressures, and the measurement time can be reduced from before.
Inventors:
MANO KAZUNE (JP)
Application Number:
PCT/JP2018/042825
Publication Date:
May 28, 2020
Filing Date:
November 20, 2018
Export Citation:
Assignee:
SHIMADZU CORP (JP)
International Classes:
G01N21/3504
Domestic Patent References:
| WO2018135619A1 | 2018-07-26 | |||
| WO2017163452A1 | 2017-09-28 |
Foreign References:
| US9261457B1 | 2016-02-16 | |||
| JPS59180458A | 1984-10-13 | |||
| JPS57127846A | 1982-08-09 | |||
| JPH06129983A | 1994-05-13 | |||
| JP2007510131A | 2007-04-19 | |||
| US8368896B1 | 2013-02-05 |
Attorney, Agent or Firm:
KYOTO INTERNATIONAL PATENT LAW OFFICE (JP)
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