The bonding of serine, phenylalanine, and mandelic acid enantiomers on an N-3,5-dinitrobenzoyl-l-leucine chiral stationary phase (on zeolite A support) has been investigated by FT-Raman spectrometry. It was found that retention is due to hydrogen bonds and π-stacking interactions between the stationary phase and the analyte. The involvement of the two different amide groups (as donor and/or acceptor) in the complexation reaction can be followed based on spectral data. A correlation was found between the ratio of the amide I and the ring stretching (1532 cm(-)(1)) bands and retention data.

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Fourier transform infrared spectroscopy has been used for in situ analysis of HBr, CH3Br, and CO within light bulbs at different stages of burning time. The interference fringes originated in the quartz walls of the bulbs have been eliminated by different methods. The NIPALS procedure yielded higher S/N ratio than the fringe-elimination method applied. The CO and HBr showed time-dependent concentration changes during the burning period. The maximum CO concentration (approximately 6 ppm) was detected after 30-50 s of burning time, and then it practically burned out after 5 h. The HBr concentration increased in the first 3 min of burning, and then its concentration stabilized at a 10-15 ppm level. After 5 s of illumination, the CH3Br concentration became undetectable.