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disk on the surface of which rests a zinc selenide plate. The position of the plate is adjusted to be
between 0.125 and 0.5 mm from the center jet of the nebulizer. The gas flow rate used for nebulization
is adjusted to be appropriate for the column flow rate, but should not exceed 80 ml/ min.

Figure 8.8
An Exploded View of the LC/FTIR Interface

It appeared from the report that although the separation was also monitored by a UV detector, the disk
was rotated manually. The disk was moved to a new position just before a peak started to elute, and just
after the elution of the peak was complete. After the separation was finished and the individual solutes
were deposited on the zinc selenide plate, the disk was removed. The spectra were measured off-line,
using a Perkin Elmer Model 1800 FT-IR spectrometer, fitted with a Spectra-Tech IR-Plan microscope.
Good spectra were reported to have obtained, and the system exhibited a very useful sensitivity. The
spectra were obtained from 60 ng of material with a signal to noise ratio of at least 9. It would also
appear that the method of deposition was very efficient, and useful spectra could