Autor: |
G. C. Rhoderick, D. Lisak, P. M. Chu, Joseph T. Hodges, J. C. Travis |
Rok vydání: |
2006 |
Předmět: |
|
Zdroj: |
SPIE Proceedings. |
ISSN: |
0277-786X |
Popis: |
Frequency-stabilized cavity ring-down absorption spectrometry (FS-CRDS) with single-mode excitation using a tunable continuous-wave diode laser is being developed to help support the delivery of reference gas concentration standards. This paper describes initial efforts to compare FS-CRDS measurements with National Institute of Standards and Technology (NIST) methane-in-air standard reference materials to demonstrate the potential of this method to deliver standards-grade measurements with uncertainties of 1 % or lower. The current work demonstrates measurements with residual standard deviations of approximately 1 % for methane sample mole fractions of 50 μmol mol -1 and above. The results for lower mole fraction samples are poorer due to the poor signal-to-noise ratios and the higher pressures required for the measurements. The current results are potentially limited by the Voigt line shape which was used to model the data. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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