AI Article Synopsis
- A new method was created to measure the absorption coefficient spectrum of tiny coal grains (down to 10^{-7}) in the C-H stretching band region (2700-3200 cm^{-1}) using infrared transflection microspectroscopy.
- The approach involved using an optimization algorithm with the Kramers-Kronig transform to accurately calculate the complex refractive index (n - ik) so that the theoretical transflection spectrum matched the experimental data.
- The resulting absorption coefficients from this method were then compared to bulk values obtained through the potassium bromide (KBr) pellet measurement technique.
Article Abstract
A method was developed to obtain the absorption coefficient spectrum of a grain of coal (as small as 10(-7)) in the region of aliphatic and aromatic C-H stretching bands (2700-3200 cm(-1)) using infrared transflection microspectroscopy. In this method, the complex refractive index n - ik was determined using an optimization algorithm with the Kramers-Kronig transform so that the calculated transflection spectrum from the Fresnel equation corresponded to the measured one. The obtained absorption coefficients were compared with the bulk values determined from the potassium bromide (KBr) pellet measurement method.
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| http://dx.doi.org/10.1366/13-07063 | DOI Listing |
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