A purged-gas containment cell for infrared absorbance measurements

Abstract

The purged gas containment cell is composed of readily available materials. This cell is charged with analyte samples under the conditions of ambient temperature and pressure. The analyte samples are obtained from dilution of commercially available pure material in lecture bottles. This is achieved by injecting pure analyte material into a Tedlar ® bags during filling with a known amount of nitrogen diluent. This study demonstrates the utility of the approach using a series of gas samples with concentration-pathlength products spanning the Beer's law range of infrared absorbances. These absorbance values and blackbody radiance levels are within the linearity range of both the active and passive Fourier transform infrared spectrometers that are used in this study. In addition, these conditions are representative of environments that are often encountered in open-air measurements.