| abstract |
The presence of trace molecules in air may be determined using an ion mobility spectrometer. Such devices may be used in the fields of explosives detection, identification of narcotics, and in applications characterized by the presence of very low airborne concentrations of organic molecules of special interest. The sensitivity of such instruments is dependent on the method of gas sampling utilized. A cyclone sampling nozzle can greatly improve the sampling efficiency, particularly when the sampling needs to be performed at a distance from the air intake. The cyclone sampling nozzle consists of an intake gas flow and a separate coaxial emitted gas flow which is deflected to move with a circular motion. |