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In-plane quartz-enhanced photoacoustic spectroscopy

Applied Physics Letters, 2020
An optical gas sensing technique based on in-plane quartz-enhanced photoacoustic spectroscopy (IP-QEPAS) is reported. In IP-QEPAS, the laser beam is aligned in the plane of the quartz tuning fork (QTF) to increase the interaction area between the acoustic wavefront and the QTF.
Yufei Ma   +6 more
openaire   +2 more sources

Quartz-Enhanced Photoacoustic Spectroscopy-Conductance Spectroscopy for Gas Mixture Analysis

Analytical Chemistry, 2023
A novel spectroscopic method, named quartz-enhanced photoacoustic spectroscopy-conductance spectroscopy (QEPAS-CS), was first developed for gas mixture analysis. In QEPAS-CS, the advantage of photoacoustic detection and conductance analysis was realized by a quartz tuning fork (QTF).
Ruobin Zhuang   +11 more
openaire   +2 more sources

Quartz-enhanced photoacoustic spectroscopy of methane isotopologues

Photonic Instrumentation Engineering VIII, 2021
We report on the detection of the isotopologues 12CH4 and 13CH4 by employing a quartz-enhanced photoacoustic spectroscopy (QEPAS)-based sensor. By properly selecting the exciting light source and the working conditions, two absorption lines, having a negligible cross-section ratio temperature coefficient of -6.7‰/°C and a cross section ratio of ~ 0.06 ...
Marilena Giglio   +10 more
openaire   +1 more source

Double acoustic microresonator quartz-enhanced photoacoustic spectroscopy

Optics Letters, 2014
Quartz-enhanced photoacoustic spectroscopy (QEPAS) based on double acoustic microresonators (AmRs) is developed and experimentally investigated. The double AmR spectrophone configuration exhibits a strong acoustic coupling between the AmR and the quartz tuning fork, which results in a ∼5  ms fast response time.
Lei, Dong   +11 more
openaire   +2 more sources

Elliptical-tube off-beam quartz-enhanced photoacoustic spectroscopy

Applied Physics Letters, 2022
We propose an elliptical-tube off-beam quartz-enhanced photoacoustic spectroscopy (EO-QEPAS) method in which an elliptical tube is employed as an acoustic resonator, instead of a circular resonator in QEPAS, to match the stripe-like beam emitted from a high-power multimode laser diode (MLD).
Zhijin Shang   +4 more
openaire   +1 more source

Off-plane quartz-enhanced photoacoustic spectroscopy

Optics Letters
In this work, we developed off-plane quartz-enhanced photoacoustic spectroscopy (OP-QEPAS). In the OP-QEPAS the light beam went neither through the prong spacing of the quartz tuning fork (QTF) nor in the QTF plane. The light beam is in parallel with the QTF with an optimal distance, resulting in low background noise. A radial-cavity (RC) resonator was
Huijian Luo   +11 more
openaire   +2 more sources

Comparison of Quartz-enhanced Photoacoustic Spectroscopy and Conventional Photoacoustic Spectroscopy based Detectors

Lasers, Sources and Related Photonic Devices, 2010
Performance of quartz-enhanced photoacoustic spectroscopy and conventional photoacoustic spectroscopy based detectors applied to trace gas sensing was compared. Nitrogen with 10 ppmv of acetylene and a diode laser accessing 6529.17 cm−1 absorption line were used.
Lei Dong   +3 more
openaire   +1 more source

Trace HCN quantification using quartz enhanced photoacoustic spectroscopy

2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006
Detection of trace HCN concentrations in dry nitrogen and ambient air was performed by means of quartz enhanced photoacoustic spectroscopy using a near-infrared DFB laser source. A normalized detection sensitivity of 2.5middot10-9 cm-1 W/radicHz was achieved.
A.A. Kosterev, F.K. Tittel
openaire   +1 more source

Ethylene Trace Detection by Quartz Enhanced Photoacoustic Spectroscopy

Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, 2009
Ethylene (C 2 H 4 ) absorption line intensity at 6172.95 cm−1 was determined for trace gas detection. C 2 H 4 trace concentration measurements were performed using quartz enhanced photoacoustic spectroscopy (QEPAS) with a sensitivity of 1.3 ppmv (1σ) for τ=1s time constant. The effect of modulation frequency accuracy on QEPAS signal was investigated.
K. Liu   +5 more
openaire   +1 more source

Quartz Enhanced Photoacoustic Spectroscopy: Today and Beyond

Lasers, Sources and Related Photonic Devices, 2010
Current theoretical understanding and practical applications of the trace gas sensing technique called quartz enhanced photoacoustic spectroscopy (QEPAS) will be presented. Work in progress and planned QEPAS developments will be discussed.
openaire   +1 more source

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