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studies. The material used by Scott et al. was silver chloride (horn silver) and the cell was gold plated
internally to reduce light absorption losses. This was a procedure introduced specifically for GC/IR
systems and will be discussed in more detail later.

Figure 4.2
The Heated IR Flow-through Cell

The trap that was attached to the IR cell was electrically heated by appropriate heater coils so that the
temperature could be maintained at 250°C. It was packed with a GC stationary phase that consisted of
15% w/w of Apiezon Grease on 60-80 BS. mesh brick dust (a high-temperature GC packing frequently
used at that time). Around the outside of the trap were a series of cooling coils carrying cold water, the
flow of which was also controlled by a programmed solenoid valve. The column was all glass 60 ft
long, 4.0 mm I.D., and packed with 60-80 BS mesh brick dust