Results 21 to 30 of about 25,059 (249)
Dual-comb quartz-enhanced photoacoustic spectroscopy
Photoacoustics, 2022 Photoacoustic spectroscopy (PAS) using two optical combs is a new-born technique, offering appealing features, including broad optical bandwidths, high resolutions, fast acquisition speeds, and wavelength-independent photoacoustic detection, for chemical
Xinyi Ren +6 more
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Photoacoustics, 2018 In a carrier flow based permeation system the measured permeation curve is the convolution of two processes: the intrinsic permeation process and the transfer of the permeated molecules through the measuring system.
Zoltán Bozóki +4 more
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Recent Advances in QEPAS and QEPTS Based Trace Gas Sensing: A Review
Frontiers in Physics, 2020 This invited review paper summarizes and discusses developments of QTF based state-of-the-art quartz-enhanced photoacoustic spectroscopy (QEPAS) and quartz-enhanced photothermal spectroscopy (QEPTS) gas sensing techniques over the past 3 years.
Yufei Ma
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Excessive alcohol consumption induces methane production in humans and rats
Scientific Reports, 2017 Various studies have established the possibility of non-bacterial methane (CH4) generation in oxido-reductive stress conditions in plants and animals.
E. Tuboly +12 more
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Float-polishing process and analysis of float-polished quartz [PDF]
, 1994 A fluid-mechanical model is developed for the float-polishing process. In this model laminar flow between the sample and the lap results in pressure gradients at the grooves that support the sample on a fluid layer. The laminar fluid motion also produces
Baselt, D. R. +4 more
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Quartz-enhanced photoacoustic spectroscopy [PDF]
Optics Letters, 2002 A new approach to detecting a weak photoacoustic signal in a gas medium is described. Instead of a gas-filled resonant acoustic cavity, the sound energy is accumulated in a high- Q crystal element. Feasibility experiments utilizing a quartz-watch tuning fork demonstrate a sensitivity of 1.2x10(-7) cm(-1) W/ radicalHz .
A A, Kosterev +3 more
openaire +2 more sources
Detection of Molecular Oxygen at Low Concentrations Using Quartz Enhanced Photoacoustic Spectroscopy
Sensors, 2010 Molecular oxygen is detected at low concentrations using photoacoustic spectroscopy despite its unfavorable photoacoustic properties. The system consists of a seed laser diode, a tapered amplifier and a quartz tuning fork based spectrophone, thus ...
Andreas Pohlkötter +3 more
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Consideration of Temperature and Slip Correction for Photothermal Spectrometry
Asian Journal of Atmospheric Environment, 2015 Temperature was considered to estimate the minimum detectable absorption coefficient of aerosol particles from photothermal spectroscopy. Light energy absorbed by subsequent emission from the aerosol results in the heating of the aerosol sample and ...
Jeonghoon Lee
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Quartz-Enhanced Photoacoustic Spectroscopy for One-Health [PDF]
EPJ Web of Conferences, 2023 We report on the development of Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS) technology to detect 8 different air pollutants, namely CH4, NO2, CO2, N2O, CO, NO, SO2 and NH3, with the same acoustic detection module and interchangeable laser sources,
Patimisco Pietro +9 more
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High-sensitivity all-optical PA spectrometer based on fast swept laser interferometry
Photoacoustics, 2022 A high-sensitivity all-optical photoacoustic spectroscopy based on fast swept laser interferometry is proposed to trace gas detection. The momentary cavity length of the fiber-optic Fabry–Perot microphone is demodulated by a fast swept-laser ...
Xuefeng Mao +4 more
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