Results 151 to 160 of about 3,338,318 (170)

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, Rafal Lewicki, Frank K. Tittel, Anatoliy A. Kosterev   +3 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, Junming Li, Haohua Lv, Jiabao Xie, Chenglong Wang, Haoyang Lin, Ruobin Zhuang, Wenguo Zhu, Yongchun Zhong, Ruifeng Kan, Jianhui Yu, Huadan Zheng   +11 more
openaire   +2 more sources

Quartz enhanced photoacoustic spectroscopy for the detection of acetone

Sixth International Conference on Optical and Photonic Engineering (icOPEN 2018), 2018
Quartz enhanced photoacoustic spectroscopy (QEPAS) is an extremely effective tool for the detection and quantification of trace gases, which offers advantages of fast response, high sensitivity and high resolution. In this paper, a gas sensor based on quartz-enhanced photoacoustic detection and an external cavity quantum cascade laser (ECQCL) was ...
Jinsong Li, Tianbo He, Sheng Zhou, Weikai Hu   +3 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

Quartz Enhanced Photoacoustic Spectroscopy for Human Breath Analysis

Frontiers in Optics 2016, 2016
Simultaneous monitoring of several trace gases requires source tunability and highly sensitive detection. To serve this purpose a MIR-OPO light source pumping a quartz-enhanced photoacoustic sensor is demonstrated. The sensor targets exhaled human breath analysis.
M. Lassen, L. Lamard, Y. Feng, A. Peremans, J. C. Petersen   +4 more
openaire   +1 more source

New developments in THz quartz enhanced photoacoustic spectroscopy

SPIE Proceedings, 2016
We will report on new developments of quartz-enhanced photo-acoustic (QEPAS) sensor employing THz quantum cascade laser (QCLs). The extension of the QEPAS technique in the THz range was made possible by the realization of custom made QTFs. With the aim to improve the QTF acousto-electric transduction efficiency, we designed and realized new QTF designs.
Spagnolo V, Patimisco P, Sampaolo A, Giglio M, Vitiello MS, Scamarcio G, Tittel FK   +6 more
openaire   +3 more sources

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, T. Wu, X. Gao, W. Zhang, E. Fertein, W. Chen   +5 more
openaire   +1 more source

Double resonant quartz-enhanced photoacoustic spectroscopy with a spherical resonator

Optics Letters
In this Letter, double resonant quartz-enhanced photoacoustic spectroscopy (QEPAS) with a spherical resonator is proposed for the first time to our knowledge. This spherical resonator, which functions both as an acoustic resonator and a gas chamber, facilitates efficient sound wave coupling between the resonator and the quartz ...
Chu Zhang, Shunda Qiao, Ying He, Yufei Ma   +3 more
openaire   +2 more sources

Quartz-Enhanced Photoacoustic Spectroscopy for Environmental Monitoring

Air pollution is a critical global issue, contributing to over 4.2 million deaths annually due to stroke, heart disease, lung cancer, and chronic respiratory diseases. It also poses significant economic and social challenges, including increased healthcare costs and reduced productivity. The need for real-time, high-resolution air quality monitoring is
Pietro Patimisco, Andrea Zifarelli, Raffaele De Palo, Mariagrazia Olivieri, Angelo Sampaolo, Vincenzo Spagnolo   +5 more
openaire   +1 more source

Tapered acoustic resonator-based quartz-enhanced photoacoustic spectroscopy

Optics Letters
In this paper, a quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor based on a novel tapered acoustic resonator (TAR) was proposed for the first time, to our knowledge. The proposed structure not only enhances acoustic signals but also substantially reduces the demands on beam quality and optical alignment, leading to ...
Chenzhao Sang, Chu Zhang, Runqiu Wang, Shunda Qiao, Ying He, Yufei Ma   +5 more
openaire   +2 more sources