Results 91 to 100 of about 909 (177)

A Mid-infrared QEPAS sensor device for TATP detection

Journal of Physics: Conference Series, 2009
Recent developments of external cavity quantum cascade lasers (EC-QC lasers) enable new applications in laser spectroscopy of trace gas species in the mid-infrared spectral region. We report the application of quartz enhanced photo acoustic spectroscopy (QEPAS) with widely tuneable EC-QC lasers as excitation sources for chemical sensing of different ...
C Bauer, U Willer, R Lewicki, A Pohlkötter, A Kosterev, D Kosynkin, F K Tittel, W Schade   +7 more
openaire   +1 more source

An electrically and optically cooperated QEPAS device for highly integrated gas sensors

, 2022
S.111-118A QEPAS device is demonstrated where the quartz tuning fork (QTF) is not only excited by a laser-induced acoustic wave but also driven electrically by a CMOS circuit at the same time.
Schade, W., Willer, U., Mordmüller, M., Köhring, M.   +3 more
core   +1 more source

Compact QEPAS sensor for trace methane and ammonia detection in impure hydrogen [PDF]

, 2011
A compact two-gas sensor based on quartz enhanced photoacoustic spectroscopy (QEPAS) was developed for trace methane and ammonia quantification in impure hydrogen.
Peters, B., Wright, J., Ferguson, B., Mcwhorter, S.   +3 more
core  

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

Simultaneous dual-gas QEPAS detection based on a fundamental and overtone combined vibration of quartz tuning fork

, 2017
A dual-gas quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor system based on a frequency division multiplexing technique of a quartz tuning fork (QTF) was developed and experimentally demonstrated.
Sampaolo A., Yin W., Yin X., Zhang L., Jia S., Ma W., Pei K., Dong L., Patimisco P., Tittel F. K., Wu H., Xiao L., Spagnolo V., Zheng H.   +13 more
core   +2 more sources

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  

QEPAS based ppb-level detection of CO and N2O using a high power CW DFB-QCL

, 2013
An ultra-sensitive and selective quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor platform was demonstrated for detection of carbon monoxide (CO) and nitrous oxide (N2O). This sensor used a stateof- the art 4.61 μm high power, continuous wave
Razeghi, Manijeh, Ma, Yufei, Tittel, Frank K., Lewicki, Rafał   +3 more
core   +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