Results 91 to 100 of about 825 (180)

Atmospheric CH4 and N2O measurements near Greater Houston area landfills using a QCL-based QEPAS sensor system during DISCOVER-AQ 2013 [PDF]

, 2014
A quartz-enhanced photoacoustic absorption spectroscopy (QEPAS)-based gas sensor was developed for methane (CH4) and nitrous-oxide (N 2O) detection. The QEPAS-based sensor was installed in a mobile laboratory operated by Aerodyne Research, Inc.
Griffin R. J., SPAGNOLO, Vincenzo Luigi, Jahjah M., Rei W., Ren W., Jiang W., Patimisco P., Tittel F. K., Jahjaj M., Sanchez N. P., Sanchez P. N., Herndon S. C., Spagnolo V.   +12 more
core   +1 more source

Influence of Tuning Fork Resonance Properties on Quartz-Enhanced Photoacoustic Spectroscopy Performance

Sensors, 2019
A detailed investigation of the influence of quartz tuning forks (QTFs) resonance properties on the performance of quartz-enhanced photoacoustic spectroscopy (QEPAS) exploiting QTFs as acousto-electric transducers is reported.
Huadan Zheng, Haoyang Lin, Lei Dong, Yihua Liu, Pietro Patimisco, John Zweck, Ali Mozumder, Angelo Sampaolo, Vincenzo Spagnolo, Bincheng Huang, Jieyuan Tang, Linpeng Dong, Wenguo Zhu, Jianhui Yu, Zhe Chen, Frank K. Tittel   +15 more
doaj   +1 more source

Quartz-Enhanced Photoacoustic Spectroscopy with Right-Angle Prism

Sensors, 2016
A right-angle prism was used to enhance the acoustic signal of a quartz-enhanced photoacoustic spectroscopy (QEPAS) system. The incident laser beam was parallelly inverted by the right-angle prism and passed through the gap between two tuning fork prongs
Yongning Liu, Jun Chang, Jie Lian, Zhaojun Liu, Qiang Wang, Zengguang Qin   +5 more
doaj   +1 more source

Fiber-Amplifier-Enhanced QEPAS Sensor for Simultaneous Trace Gas Detection of NH3 and H2S

, 2015
A selective and sensitive quartz enhanced photoacoustic spectroscopy (QEPAS) sensor, employing an erbium-doped fiber amplifier (EDFA), and a distributed feedback (DFB) laser operating at 1582 nm was demonstrated for simultaneous detection of ammonia (NH3)
Suotang Jia, Huadan Zheng, Wangbao Yin, Xukun Yin, Weiguang Ma, Lei Zhang, Hongpeng Wu, Lei Dong, Xiaoli Liu   +8 more
core   +1 more source

Measurement precision improving with adaptive Kalman filter for quartz-enhanced photoacoustic spectroscopy methane sensor

AIP Advances
Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS) has shown significant progress in trace gas sensing in recent years; however, its detection performance remains constrained by system noise.
Yu Zhou, Li Wang, Yingchao Xie, Hao Xiong, Qilei Zhang, Shenlong Zha   +5 more
doaj   +1 more source

Sub-parts-per-billion level detection of SF6 with a fiber-coupled QCL-QEPAS sensor

, 2012
The detection and quantification of trace chemical species in the gas phase is of great interest in a wide range of applications such as environmental monitoring, industrial process control and medical diagnostics.
Kriesel J., Scamarcio G, SPAGNOLO, Vincenzo Luigi, Patimisco P, Bernacki B. E, . Borri S   +5 more
core  

Intrinsic Spectral Resolution Limitations of QEPAS Sensors for Fast and Broad Wavelength Tuning

, 2020
Quartz-enhanced photoacoustic sensing is a promising method for low-concentration trace-gas monitoring due to the resonant signal enhancement provided by a high-Q quartz tuning fork.
Jan C. Petersen, Ming-Hsien Chou, Jesper B. Christensen, Mikael Lassen, Lasse Høgstedt, Søren M. M. Friis, Jui-Yu Lai, David Balslev-Harder   +7 more
core   +1 more source

Absorption spectroscopy of CO2 at 4.3 m utilizing an off-beam QEPAS Spectrophone and an IR-LED

, 2022
2 S.An IR-LED at 4.3 m and an off-beam QEPAS spectrophone as optical detector are utilized for absorption spectroscopy.
Schade, W., Böttger, S., Willer, U.
core  

HCN ppt-level detection based on a QEPAS sensor with amplified laser and a miniaturized 3D-printed photoacoustic detection channel

, 2018
Ultra-high sensitive and stable detection of hydrogen cyanide (HCN) based on a quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor was realized using an erbium-doped fiber amplifier (EDFA) as well as a miniaturized 3D-printed photoacoustic ...
Yu, Xin, He, Ying, Ma, Yufei, Tittel, Frank K., Tong, Yao   +4 more
core   +1 more source

1D U-Net Enhanced QEPAS Sensor for Trace Water Vapor Detection

Optics
We report a deep learning-assisted quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor for trace water vapor detection in air. A 1392 nm butterfly-packaged DFB laser is wavelength-modulated at f0/2, and the QEPAS signal is retrieved by second ...
Huiming Xiao, Jiahui Wu, Haoyang Lin, Lihao Wang, Jianfeng He, Leqing Lin, Ruobin Zhuang, Guantian Hong, Jiabao Xie, Jianhui Yu, Wenguo Zhu, Yongchun Zhong, Zhigang Song, Huadan Zheng   +13 more
doaj   +1 more source