Abstract

An experimental setup for kinetic and product studies in a flow system has been developed. For detection, a nonresonant optoacoustic technique combined with a tunable lead-salt diode laser has been employed. The performance of the system was tested on ammonia in argon, and a detection limit (S/N = 2) of 8 × 10¹² molecules cm^-3 (corresponding to 320 ppb at atmospheric pressure) was obtained at a pressure of about 7 kPa when frequency modulation was employed. At 1.5 kPa the detection limit was about 2 × 10¹⁴ molecules cm^-3. With a multipass cell the sensitivity was increased by a factor of four.

Optoacoustic trace-gas monitoring with near-infrared diode lasers

Miklós Fehér, Yuan Jiang, John P. Maier, and András Miklós
Appl. Opt. 33(9) 1655-1658 (1994)

Pulsed laser optoacoustic detection of flame species

Gregory P. Smith, Mark J. Dyer, and David R. Crosley
Appl. Opt. 22(24) 3995-4003 (1983)

Diode laser measurements of trace concentrations of ammonia in an entrained-flow coal reactor

Joel A. Silver, David S. Bomse, and Alan C. Stanton
Appl. Opt. 30(12) 1505-1511 (1991)

Quantum noise-limited FM spectroscopy with a lead-salt diode laser

Clinton B. Carlisle, David E. Cooper, and Horst Preier
Appl. Opt. 28(13) 2567-2576 (1989)

Two-tone optical heterodyne spectroscopy with a tunable lead-salt diode laser

David E. Cooper and J. P. Watjen
Opt. Lett. 11(10) 606-608 (1986)