Results 21 to 30 of about 11,035 (147)
Photoacoustic correlation technique for low-speed flow measurement [PDF]
SPIE Proceedings, 2010 A photoacoustic correlation spectroscopy (PACS) technique was proposed for the first time. This technique is inspired by its optical counterpart-the fluorescence correlation spectroscopy (FCS), which is widely used in the characterization of the dynamics of fluorescent species.
Sung-Liang, Chen +5 more
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Photoacoustic Techniques for Trace Gas Sensing Based on Semiconductor Laser Sources
Sensors, 2009 The paper provides an overview on the use of photoacoustic sensors based on semiconductor laser sources for the detection of trace gases. We review the results obtained using standard, differential and quartz enhanced photoacoustic techniques.
Vincenzo Spagnolo +3 more
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Biosensors, 2022 The photoacoustic (PA) effect occurs when sound waves are generated by light according to the thermodynamic and optical properties of the materials; they are absorption spectroscopic techniques that can be applied to characterize materials that absorb ...
Unsang Jung, Jaemyung Ryu, Hojong Choi
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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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Whole-Body Photoacoustic Imaging Techniques for Preclinical Small Animal Studies
Sensors, 2022 Photoacoustic imaging is a hybrid imaging technique that has received considerable attention in biomedical studies. In contrast to pure optical imaging techniques, photoacoustic imaging enables the visualization of optical absorption properties at deeper
Hyunjun Kye +4 more
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Comparison of photoacoustic spectroscopy and cavity ring-down spectroscopy for ambient methane monitoring at Hohenpeißenberg [PDF]
Atmospheric Measurement Techniques, 2023 With an atmospheric concentration of approximately 2000 parts per billion (ppbV, 10−9), methane (CH4) is the second most abundant greenhouse gas (GHG) in the atmosphere after carbon dioxide (CO2).
M. Müller +9 more
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Frontiers in Physics, 2022 Photoacoustic imaging can be used to extract functional information at the molecular level for imaging the whole body of small animals in vivo. However, the use of a mechanical scanner to image the whole body involves acquiring the data for a period of ...
Haeni Lee +6 more
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Scientific Reports, 2017 Photoacoustic sensing and imaging techniques have been studied widely to explore optical absorption contrast based on nanosecond laser illumination. In this paper, we report a long laser pulse induced dual photoacoustic (LDPA) nonlinear effect, which ...
Fei Gao +6 more
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Sensors, 2021 Multispectral photoacoustic imaging is a powerful noninvasive medical imaging technique that provides access to functional information. In this study, a set of methods is proposed and validated, with experimental multispectral photoacoustic images used ...
Aneline Dolet +6 more
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Photoacoustic investigation of QCL modulation techniques
Journal of Physics: Conference Series, 2010 High detection sensitivity and spectral selectivity is important for gas analysers to identify the measured compound and to detect low concentrations. We investigated three different modulation methods – pulse gate modulation, pulse frequency modulation and chopper modulation – for a new pulsed quantum cascade laser based photoacoustic sensor.
M Germer, M Wolff
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