Publication
Methane monitoring by near infrared photoacoustic spectroscopy: The importance of relaxation phenomena
Related publications (24)
Multi-hydrogenated compounds monitoring in optical fibre manufacturing process by photoacoustic spectroscopy
Luc Thévenaz, Jean-Philippe Besson
Sub-ppm hydrogen chloride (HCl) and water vapour (H2O) monitoring using photoacoustic spectroscopy in optical fibre manufacturing is reported. The development and performance of a sensor based on an acoustic resonant configuration is described, and on-site ...
Springer Verlag2006Optical, electrical and mechanical properties of the tantalum oxynitride thin films deposited by pulsing reactive gas sputtering
Thin films of tantalum oxynitride were prepared by reactive magnetron sputtering using a Ta target and N2 and O2 as reactive gases. The nitrogen flow was kept constant while the oxygen flow was pulsed periodically. The film composition evolves progressivel ...
2006Methane monitoring by near infrared photoacoustic spectroscopy: the importance of relaxation phenomena
Luc Thévenaz, Jean-Philippe Besson
The importance of molecular relaxation in photoacoustic spectroscopy is discussed. The particular case of methane monitoring in dry oxygen using a 1.65-μm laser-based photoacoustic sensor is reported. The slow vibration-to-translation energy transfer occur ...
EDP Sciences2005Individually ventilated cages microclimate monitoring using photoacoustic spectroscopy
Luc Thévenaz, Jean-Philippe Besson, Marcel Gyger
A multi-gas photoacoustic sensor was developed In order to monitor microclimatic parameters at ppm level from the atmosphere of Individually ventilated cages housing mice. Ammonia, water vapour and carbon dioxide were measured on-line and in real-time duri ...
VDI Verlag GMBH2004Sub-ppm multi gas sensing based on photoacoustic spectroscopy using DFB laser diodes
Luc Thévenaz, Jean-Philippe Besson
Sensitive photoacoustic detection of methane (CH4), hydrogen chloride (HCI) and water vapour (H2O) in the near-infrared range using semiconductor DFB lasers is reported. A detection limit of 0.17 ppm of CH4, 0.2 ppm of HCI and 0.024 ppm of H2O (signal-to-n ...
VDI Verlag GMBH2004Multi-gas sensing based on photoacoustic spectroscopy using tunable laser diodes
Luc Thévenaz, Jean-Philippe Besson
Multi-hydrogenated compounds detection based on photoacoustic (PA) spectroscopy is reported. Three near-infrared semiconductor lasers are used with a resonant PA cell operated in its first longitudinal mode to monitor methane, water vapour and hydrogen chl ...
Elsevier2004Development and application of UV-visible and mid-IR differential absorption spectroscopy techniques for pollutant trace gas monitoring
Spatial representativeness is an important quality criterion in trace gas monitoring, especially if measurements are intended for regulatory and model validation purposes. Open-path absorption spectroscopy techniques meet the representativeness requirement ...
EPFL2004Ammonia monitoring at trace level using photoacoustic spectroscopy in industrial and environmental applications
An ammonia traces analyser based on photoacoustic spectroscopy is described. The system uses a CO2 laser and a properly designed resonant photoacoustic cell to achieve ammonia detection at sub-parts-per- billion (ppb) level. The instrument features unatten ...
Elsevier2004Application of antimonide diode lasers in photoacoustic spectroscopy
First investigations of photoacoustic (PA) spectroscopy (PAS) of methane using an antimonide semiconductor laser are reported. The laser fabrication is made in two steps. The structure is firstly grown by molecular beam epitaxy, then a metallic distributed ...
Elsevier2004Mesure de traces de gaz à l'aide de lasers à semi-conducteur
Infrared spectroscopy using semiconductor lasers is a promising technique for trace gas detection. It allows a continuous and real time monitoring of several species, with a high sensitivity and a good selectivity. Among all the possible methods two are pa ...
EPFL2002