Quartz-enhanced photoacoustic spectroscopy (QEPAS) and Beat Frequency-QEPAS techniques for air pollutants detection: A comparison in terms of sensitivity and acquisition time [PDF]
Photoacoustics, 2023 In this work, a comparison between Quartz Enhanced Photoacoustic Spectroscopy (QEPAS) and Beat Frequency-QEPAS (BF-QEPAS) techniques for environmental monitoring of pollutants is reported.
Giansergio Menduni +2 more
exaly +7 more sources
High-sensitivity methane detection based on QEPAS and H-QEPAS technologies combined with a self-designed 8.7 kHz quartz tuning fork [PDF]
Photoacoustics, 2023 Methane (CH4) is a greenhouse gas as well as being flammable and explosive. In this manuscript, quartz-enhanced photoacoustic spectroscopy (QEPAS) and heterodyne QEPAS (H-QEPAS) exploring a self-designed quartz tuning fork (QTF) with resonance frequency (
Tiantian Liang +4 more
doaj +5 more sources
Planar Laser-Based QEPAS Trace Gas Sensor [PDF]
Sensors, 2016 A novel quartz enhanced photoacoustic spectroscopy (QEPAS) trace gas detection scheme is reported in this paper. A cylindrical lens was employed for near-infrared laser focusing.
, Rui Sun, Frank K Tittel
exaly +7 more sources
Development of Compact Electronics for QEPAS Sensors [PDF]
SensorsRemarkable advances in Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS) made it one of the most effective gas-sensing techniques in terms of sensitivity and selectivity. Consequently, its range of possible applications is continuously expanding, but in
Luigi Lombardi +2 more
exaly +7 more sources
Assessment of vibrational-translational relaxation dynamics of methane isotopologues in a wet-nitrogen matrix through QEPAS [PDF]
Photoacoustics, 2023 Here we report on a study of the non-radiative relaxation dynamic of 12CH4 and 13CH4 in wet nitrogen-based matrixes by using the quartz-enhanced photoacoustic spectroscopy (QEPAS) technique.
Mariagrazia Olivieri +9 more
doaj +5 more sources
High-Power DFB Diode Laser-Based CO-QEPAS Sensor: Optimization and Performance
Sensors, 2018 A highly sensitive carbon monoxide (CO) trace gas sensor based on quartz-enhanced photoacoustic spectroscopy (QEPAS) was demonstrated. A high-power distributed feedback (DFB), continuous wave (CW) 2.33 μm diode laser with an 8.8 mW output power was used ...
, Yao Tong, Xin Yu
exaly +4 more sources
Improving the Signal to Noise Ratio of QTF Preamplifiers Dedicated for QEPAS Applications
Applied Sciences (Switzerland), 2020 The signal-to-noise ratio (SNR) is a major factor that limits the detection sensitivity of quartz-enhanced photoacoustic spectroscopy (QEPAS) sensors. The higher the electrical signal level compared to the noise amplitude is the lower the concentration ...
Piotr Z Wieczorek +2 more
exaly +4 more sources
Sensors, 2017 All the preamplifiers dedicated for Quartz Enhanced PhotoAcoustic Spectroscopy (QEPAS) applications that have so far been reported in the literature have been based on operational amplifiers working in transimpedance configurations.
Tomasz Starecki, Piotr Z Wieczorek
exaly +4 more sources
SNR Improvement of QEPAS System by Preamplifier Circuit Optimization and Frequency Locked Technique
Photonic Sensors, 2018 Preamplifier circuit noise is of great importance in quartz enhanced photoacoustic spectroscopy (QEPAS) system. In this paper, several noise sources are evaluated and discussed in detail.
Qinduan Zhang +2 more
exaly +4 more sources
Towards low-cost QEPAS sensors for nitrogen dioxide detection
Photoacoustics, 2020 Increasing awareness of the adverse health effects of air pollution leads to a demand of low-cost sensors for the measurement of pollutants such as NO2.
B Schweighofer, H Wegleiter, M Knoll
exaly +5 more sources