Results 21 to 30 of about 1,306,141 (231)

Near infrared spectroscopy for fibre based gas detection [PDF]

, 2010
Gas sensing systems based on fibre optic linked near infra red absorption cells are potentially a flexible and effective tool for monitoring accumulations of hazardous and noxious gases in enclosed areas such as tunnels and mines.
Culshaw, B., Johnstone, W., Thursby, G.J., Stewart, G.   +3 more
core   +4 more sources

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, I. Salma, Z. Németh, Z. Németh, T. Weidinger, W. Maenhaut, M. Claeys, M. Molnár, I. Major, T. Ajtai, N. Utry, Z. Bozóki   +11 more
doaj   +1 more source

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, Ming Yan, Zhaoyang Wen, Hui Ma, Ran Li, Kun Huang, Heping Zeng   +6 more
doaj   +1 more source

Correlation of trans-Lycopene Measurements by the HPLC Method with the Optothermal and Photoacoustic Signals and the Color Readings of Fresh Tomato Homogenates [PDF]

, 2009
The trans-lycopene content of fresh tomato homogenates was assessed by means of the laser photoacoustic spectroscopy, the laser optothermal window, micro-Raman spectroscopy, and colorimetry; none of these methods require the extraction from the product ...
Ksenija Marković, Charlotte van Twisk, Bicanic, D., Dane Bicanic, Bicanic, Dane, Bicanic, D.D., Dimitrovski, Darko, Buijnsters, J.G., Markovic, Ksenija, Buijnsters, Josephus Gerardus, van Twisk, C., Twisk, C., van, Otto Dóka, Luterotti, S., Luterotti, Svjetlana, Doka, O., Doka, Otto, Darko Dimitrovski, Dimitrovski, D., van Twisk, Charlotte, Svjetlana Luterotti, Markovic, K., Josephus G. Buijnsters, Twisk, C. van   +23 more
core   +1 more source

Cantilever-Enhanced Photoacoustic Spectroscopy of Radioactive Methane [PDF]

, 2020
We report the first high-resolution spectroscopy study of radiocarbon methane, 14CH4. Several absorption lines of the fundamental vibrational band n3 were measured using a continuous-wave mid-infrared optical parametric oscillator with cantilever ...
Lauri Halonen, Vainio, Markku, Halonen, L., Juho Karhu, Karhu, J., Teemu Tomberg, Markus Metsälä, Genoud, G., Markku Vainio, Hieta, Tuomas, Vainio, M., Tuomas Hieta, Tomberg, T., Tomberg, Teemu, Larnimaa, S., Metsälä, Markus, Hieta, T., Karhu, Juho, Halonen, Lauri, Guillaume Genoud, Larnimaa, Santeri, Genoud, Guillaume, Metsälä, M., Santeri Larnimaa   +23 more
core   +1 more source

Photoacoustic detection based permeation measurements: Case study for separation of the instrument response from the measured physical process

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, Tibor Guba, Tibor Ajtai, Anna Szabó, Gábor Szabó   +4 more
doaj   +1 more source

Quantitative analysis of a closed photoacoustic cell that uses a high compliance piezoelectric transducer [PDF]

, 2005
A treatment of the operation of low-frequency closed photoacoustic cells is presented, which considers the compliance of various cell elements. The optimum detector, according to our predictions, has a sensor whose compliance is large compared to that
Johnson, Mark, Jane Hodgkinson, Hodgkinson, Jane, John P. Dakin, Dakin, John P., Mark Johnson   +5 more
core   +1 more source

Optical gas sensing: a review [PDF]

, 2013
The detection and measurement of gas concentrations using the characteristic optical absorption of the gas species is important for both understanding and monitoring a variety of phenomena from industrial processes to environmental change.
Hodgkinson, Jane, Tatam, Ralph P.
core   +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, R. Molnár, T. Tőkés, R. N. Turányi, P. Hartmann, A. T. Mészáros, G. Strifler, I. Földesi, A. Siska, A. Szabó, Á. Mohácsi, G. Szabó, M. Boros   +12 more
doaj   +1 more source