Abstract:
The peak positions and half-widths of the Q-branch of the ν1 band, as well as the ratios of intensities of the Q-branches of ν3 and 2ν2 bands of methane in a methane–helium mixture are measured at various pressures and concentrations. An empirical model has been developed for estimation of the helium concentration in a methane-bearing medium by measuring these spectral parameters. The error in the He concentration is found to be less than 1% when using the ν1 band half-width. The ways of developing this technique and increasing its accuracy are considered.
Keywords:
methane, helium, Raman spectroscopy, gas analysis
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