Abstract: Method and device for identifying gases and/or ion mobility spectrometer and method for offsetting residual humidity are provided. The object of the invention is to develop a generic method for offsetting residual humidity in an ion mobility spectrometer and a related device, which has a simple structure and which fully exploits the reduced diffusion. This is achieved by a variable drift chamber drift gas velocity, which leads to differing penetration depths of the humidity into the drift chamber, and thus to variable residual humidities in the drift chamber. Methods of this type and the associated devices for detecting and identifying gases are used to recognise and identify chemical compounds, in particular explosive materials or material compounds and/or those which are damaging to health, and which must be identified in very low concentrations.

Abstract: Method and device for identifying gases and/or ion mobility spectrometer and method for offsetting residual humidity are provided. The object of the invention is to develop a generic method for offsetting residual humidity in an ion mobility spectrometer and a related device, which has a simple structure and which fully exploits the reduced diffusion. This is achieved by a variable drift chamber drift gas velocity, which leads to differing penetration depths of the humidity into the drift chamber, and thus to variable residual humidities in the drift chamber. Methods of this type and the associated devices for detecting and identifying gases are used to recognise and identify chemical compounds, in particular explosive materials or material compounds and/or those which are damaging to health, and which must be identified in very low concentrations.

Abstract: The invention relates to identifying not easily volatilized substances, in particular hazardous material, in a gas phase. A measurement cell and gas supply installations connected to the measurement cell are heated, and a plasmonic surface arranged in the measurement cell is temperature-controlled such that the plasmonic surface has a lower temperature than the measurement cell and the gas supply installations. The gas phase is guided through the gas supply installations into the measurement cell such that the gas phase reaches the plasmonic surface. Substances adsorbed out of the gas phase on the plasmonic surface are analyzed by an optical process. Surface-enhanced Raman spectroscopy or surface-enhanced infrared spectroscopy may be used. Selectivity can be increased by combining both methods. Selectivity can be additionally increased by using a gas detector, preferably an ion-mobility spectrometer. Thus the false alarm rate is reduced without a loss of time.