Resonant photoacoustic cell for pulsed laser analysis of gases at high temperature.
A new approach to high temperature gas analysis by means of photoacoustic (PA) spectroscopy is presented. The transverse modes of the resonant PA cell were excited with a pulsed laser and detected with a microphone. Changes in the properties of the PA cell resulting from a varying temperature are discussed and considered when processing the PA signal. The feasibility of the proposed method was demonstrated by studying PA response from saturated vapor of potassium chloride (KCl) in the temperature range extending from 410 to 691 degrees C. The PA spectrum, the detection limit, and the signal saturation of KCl vapor are discussed. At 245 nm excitation wavelength and 300 microJ pulse energy, the achieved detection limit for KCl is 15 ppb.
Sorvajärvi
Tapio
T
Department of Physics, Optics Laboratory, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland.
Manninen
Albert
A
Toivonen
Juha
J
Saarela
Jaakko
J
Hernberg
Rolf
R