New Signal Processing for Fast and Accurate QEPAS Measurements [PDF]
2018 IEEE International Ultrasonics Symposium (IUS), 2018 Quartz Enhanced Photoacoustic Spectroscopy (QEPAS) gas sensors have been widely developed over the last decade. This technique takes advantage of a high quality factor micro tuning fork to enable high detectivity & high selectivity miniature gas sensors.
Ranhael Levy +3 more
core +5 more sources
Passive Electrical Damping of a Quartz Tuning Fork as a Path to Fast Resonance Tracking in QEPAS
Sensors, 2021 In Quartz-Enhanced PhotoAcoustic Spectroscopy (QEPAS) gas sensors, the acoustic wave is detected by the piezoelectric Quartz Tuning Fork (QTF). Due to its high-quality factor, the QTF can detect very low-pressure variations, but its resonance can also be
Roman Rousseau +4 more
doaj +2 more sources
Greenhouse Gases Detection Exploiting a Multi-Wavelength Interband Cascade Laser Source in a Quartz-Enhanced Photoacoustic Sensor [PDF]
SensorsThis study presents the performance of a multi-gas sensor for greenhouse detection based on quartz-enhanced photoacoustic spectroscopy (QEPAS). The QEPAS sensor exploits an innovative, compact three-wavelength laser module as excitation source.
Raffaele De Palo +10 more
doaj +2 more sources
A Deep Learning Approach to Investigating Clandestine Laboratories Using a GC-QEPAS Sensor [PDF]
ChemosensorsIllicit drug production in clandestine laboratories involves the use of large quantities of different chemicals that can be obtained for legitimate purposes.
Giorgio Felizzato +5 more
doaj +3 more sources
Recent Advances in QEPAS and QEPTS Based Trace Gas Sensing: A Review
Frontiers in Physics, 2020 This invited review paper summarizes and discusses developments of QTF based state-of-the-art quartz-enhanced photoacoustic spectroscopy (QEPAS) and quartz-enhanced photothermal spectroscopy (QEPTS) gas sensing techniques over the past 3 years.
exaly +3 more sources
Effect of gas turbulence in quartz-enhanced photoacoustic spectroscopy: A comprehensive flow field analysis [PDF]
PhotoacousticsHere we present a computational and experimental fluid dynamics study for the characterization of the flow field within the gas chamber of a Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS) sensor, at different flow rates at the inlet of the chamber ...
Andrea Zifarelli +9 more
doaj +2 more sources
Off-Beam Acoustic Micro-Resonator for QEPAS Sensor with a Custom Quartz Tuning Fork
AtmosphereQuartz-enhanced photoacoustic spectroscopy (QEPAS) has shown great promise for monitoring greenhouse gases and pollutants with a high measurement accuracy and limit of detection.
Yong Wang +8 more
doaj +2 more sources
Quartz Enhanced Photoacoustic Spectroscopy on Solid Samples [PDF]
SensorsQuartz-Enhanced Photoacoustic Spectroscopy (QEPAS) is a technique in which the sound wave is detected by a quartz tuning fork (QTF). It enables particularly high specificity with respect to the excitation frequency and is well known for an ...
Judith Falkhofen +3 more
doaj +2 more sources
Sub-ppb level HCN photoacoustic sensor employing dual-tube resonator enhanced clamp-type tuning fork and U-net neural network noise filter [PDF]
PhotoacousticsHydrogen cyanide (HCN) is a toxic industrial chemical, necessitating low-level detection capabilities for safety and environmental monitoring. This study introduces a novel approach for detecting hydrogen cyanide (HCN) using a clamp-type custom quartz ...
Lihao Wang +11 more
doaj +2 more sources
Optics & Laser TechnologyThis paper presents a comparison between quartz-enhanced photoacoustic spectroscopy (QEPAS) and beat-frequency QEPAS (BF-QEPAS) techniques for the sequential detection of methane (C1) and ethane (C2) in the near-infrared spectral range.
Luigi Melchiorre +6 more
openaire +2 more sources