A Quick-Mounting Sample Holder for Infrared Work We have recently been n~nnirrglarge numbers of Nujol mulls on a Perkin-Elmer hlodel 137 Infmeord. The fitandud sample
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Journal o f Chemical Education
holder, with its retaining plate mounted with four knurled nuts, was found to be inconvenient in use. First, there was the simple, but tiresome, matter of screwing the nuts on and off the four long screws for each sample run. In addition, overtightening led to occasional cracking of salt plates, even when a rubber gasket ring (another inconvenience) was used. We have solved all of these problems by making spring retaining clipsfrom suitably cut and bent 2-in. safety pins. No rubber gasket is necessary t o protect the salt plates and assembly and disassembly of the cell is done virtually instantaneously.
