Patent ID: 7847935
Filing Date: 2010-12-07
Classification: G01N

Abstract:
1. A gas concentration quantitative analysis method for quantitatively obtaining a concentration of a trace component contained in a sample gas with use of an FTIR (Fourier transform infrared spectrophotometer), the concentration being unknown, the method comprising the steps of: specifying a sample gas and a measurement wavenumber region thereof; specifying a background gas which is not absorbed in said measurement wavenumber region; conducting an FTIR measurement of said background gas to obtain a single beam spectrum SB(BG) and a synthetic single beam spectrum SSB(BG); conducting an FTIR measurement of said sample gas to obtain a single beam spectrum SB(Samp) and a synthetic single beam spectrum SSB(Samp); calculating a double synthetic absorbance spectrum DSAbs of said sample gas as expressed by the following formula: according to the single beam spectrum SB(BG) of said background gas, the synthetic single beam spectrum SSB(BG) of said background gas, the single beam spectrum SB(Samp) of said sample gas and the synthetic single beam spectrum SSB(Samp) of said sample gas; and obtaining the concentration of a trace component contained in said sample gas according to said double synthetic absorbance spectrum.