Year
1984
Abstract
The Phemto-Chem® Model 100 Ion Mobility Spectrometer (IMS) operates in air and measures a number of explosive vapors at levels as low as partsper- trillion in seconds. The theory and operation of this instrument is discussed. The IMS inhales the vapor sample in a current of air and generates characteristic ions which are separated by time-of -ion drift in the atmospheric pressure gas. Quantitative results, using a dilution tunnel and standard signal generator with TNT, nitroglycerine, ethylene glycol dinitrate, cyclohexanone, methylamine, octafluoronaphthalene and hexafluorobenzene, are given. Rapid sample treatment with sample concentrations, microprocessor signal readout and chemical identification, offer a realistic opportunity of rapid explosive vapor detection at levels down to 10\"11* parts by volume in air.