Abstract
The detection of propane with the use of ATR spectroscopy at 3.3 µm, as the gas diffuses through the Teflon® cladding of a fluoride optical fiber, is reported. A theoretical expression for the time-dependent absorbance of the fiber sensor as a function of diffusion coefficient and cladding dimensions is developed. The experimental data fitted to the model give a diffusion coefficient of 8.85 × 10−14 m2 s−1 for propane in Teflon®. The potential of the technique for remote or distributed sensing of hydrocarbons is discussed.
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