Results 31 to 40 of about 1,555,141 (308)
Photoacoustics, 2022 Photoacoustic spectroscopy (PAS) combines the advantages of high sensitivity, high specificity and zero background, which is very suitable for trace gas detection.
Yonggang Yin +4 more
doaj +1 more source
Non-contact quartz-enhanced photoacoustic spectroscopy
Applied Physics Letters, 2023 Non-contact quartz-enhanced photoacoustic spectroscopy (NC-QEPAS) was proposed and developed for trace gas analysis. The NC-QEPAS aims at solving the problem that the quartz tuning fork (QTF) must be immersed in the gases for photoacoustic wave ...
Haoyang Lin +8 more
semanticscholar +1 more source
Source apportionment of carbonaceous chemical species to fossil fuel combustion, biomass burning and biogenic emissions by a coupled radiocarbon–levoglucosan marker method [PDF]
Atmospheric Chemistry and Physics, 2017 An intensive aerosol measurement and sample collection campaign was conducted in central Budapest in a mild winter for 2 weeks. The online instruments included an FDMS-TEOM, RT-OC/EC analyser, DMPS, gas pollutant analysers and meteorological sensors ...
I. Salma +11 more
doaj +1 more source
Applications of Near Infrared Photoacoustic Spectroscopy for Analysis of Human Respiration: A Review
Molecules, 2020 In this review, applications of near-infrared photoacoustic spectroscopy are presented as an opportunity to evaluate human respiration because the measurement of breath is fast, intact and simple to implement.
Dan C. Dumitras +3 more
doaj +1 more source
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
doaj +1 more source
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
doaj +1 more source
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
doaj +1 more source
Photoacoustic spectroscopy of bacteriorhodopsin photocycle
Biophysical Journal, 1983 Photoacoustic spectroscopy was applied to study the energetics and the kinetics of the slow intermediates of the bacteriorhodopsin photocycle. An analysis of the modulation frequency dependence of the photoacoustic signal allowed us to estimate the enthalpy changes and the kinetic parameters associated with those intermediates.
M. Delmelle, P. Thirion, M. Renard
openaire +3 more sources
Direct Absorption and Photoacoustic Spectroscopy for Gas Sensing and Analysis: A Critical Review
Laser & Photonics Reviews, 2022 Optical spectroscopy has a broad scientific basis in chemistry, physics, and material science, with diverse applications in medicine, pharmaceuticals, agriculture, and environmental monitoring.
A. Fathy +4 more
semanticscholar +1 more source
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
core +1 more source