Results 21 to 30 of about 1,487 (151)

Canopy-scale flux measurements and bottom-up emission estimates of volatile organic compounds from a mixed oak and hornbeam forest in northern Italy [PDF]

Atmospheric Chemistry and Physics, 2016
This paper reports the fluxes and mixing ratios of biogenically emitted volatile organic compounds (BVOCs) 4 m above a mixed oak and hornbeam forest in northern Italy.
W. J. F. Acton, S. Schallhart, B. Langford, A. Valach, A. Valach, P. Rantala, S. Fares, G. Carriero, R. Tillmann, S. J. Tomlinson, U. Dragosits, D. Gianelle, D. Gianelle, C. N. Hewitt, E. Nemitz   +14 more
doaj   +1 more source

First eddy covariance flux measurements by PTR-TOF [PDF]

Atmospheric Measurement Techniques, 2010
The recently developed PTR-TOF instrument was evaluated to measure methanol fluxes emitted from grass land using the eddy covariance method. The high time resolution of the PTR-TOF allowed storing full mass spectra up to <i>m/z</i> 315 with a
M. Müller, M. Graus, T. M. Ruuskanen, R. Schnitzhofer, I. Bamberger, L. Kaser, T. Titzmann, L. Hörtnagl, G. Wohlfahrt, T. Karl, A. Hansel   +10 more
doaj   +1 more source

Real-time measurement of phase partitioning of organic compounds using a proton-transfer-reaction time-of-flight mass spectrometer coupled to a CHARON inlet [PDF]

Atmospheric Measurement Techniques, 2023
Understanding the gas–particle partitioning of semivolatile organic compounds (SVOCs) is of crucial importance in the accurate representation of the global budget of atmospheric organic aerosols. In this study, we quantified the gas- vs.
Y. Peng, Y. Peng, H. Wang, Y. Gao, S. Jing, S. Zhu, D. Huang, P. Hao, S. Lou, T. Cheng, T. Cheng, C. Huang, X. Zhang   +12 more
doaj   +1 more source

Real-Time Non-Invasive Monitoring of Short-Chain Fatty Acids in Exhaled Breath

Frontiers in Chemistry, 2022
Short-chain fatty acids (SCFAs) are important metabolites produced by the gut microbiome as a result of the fermentation of non-digestible polysaccharides.
Joris Meurs, Evangelia Sakkoula, Simona M. Cristescu   +2 more
doaj   +1 more source

Towards the Use of Metabolic Volatiles in Breath for Determining Drug Response: Gstachamine as an Unlabeled Substrate to Measure CYP3A4 Activity. [PDF]

ChemMedChem
A potential substrate, gstachamine, was engineered for a future CYP3A4 assay. HepG2 cell clones overexpressing CYP3A4 were used to investigate both liquid and headspace phases after incubation. A specific N‐dealkylated metabolite and butanone were detected using LC‐MS and PTR‐ToF‐MS, respectively.
Stock V, Hofer R, Liedl KR, Troppmair J, Langer T, Gstach H, Dank C, Kammerer S, Ruzsanyi V.   +8 more
europepmc   +2 more sources

On the development of a new prototype PTR-ToF-MS instrument and its application to the detection of atmospheric amines [PDF]

Atmospheric Measurement Techniques, 2022
We herein report on the development of a new prototype PTR-ToF-MS (proton-transfer-reaction time-of-flight mass spectrometry) instrument that combines a hollow cathode glow discharge (HCGD) ion source with a focusing ion–molecule reactor (FIMR), which ...
A. Håland, A. Håland, T. Mikoviny, E. E. Syse, A. Wisthaler, A. Wisthaler   +5 more
doaj   +1 more source

Non-methane organic gas emissions from biomass burning: identification, quantification, and emission factors from PTR-ToF during the FIREX 2016 laboratory experiment [PDF]

Atmospheric Chemistry and Physics, 2018
Volatile and intermediate-volatility non-methane organic gases (NMOGs) released from biomass burning were measured during laboratory-simulated wildfires by proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF).
A. R. Koss, A. R. Koss, A. R. Koss, A. R. Koss, K. Sekimoto, K. Sekimoto, K. Sekimoto, J. B. Gilman, V. Selimovic, M. M. Coggon, M. M. Coggon, K. J. Zarzana, K. J. Zarzana, B. Yuan, B. Yuan, B. Yuan, B. M. Lerner, B. M. Lerner, B. M. Lerner, S. S. Brown, S. S. Brown, J. L. Jimenez, J. L. Jimenez, J. Krechmer, J. Krechmer, J. Krechmer, J. M. Roberts, C. Warneke, C. Warneke, R. J. Yokelson, J. de Gouw, J. de Gouw, J. de Gouw   +32 more
doaj   +1 more source

Gas-to-particle partitioning of major biogenic oxidation products: a study on freshly formed and aged biogenic SOA [PDF]

Atmospheric Chemistry and Physics, 2018
Secondary organic aerosols (SOAs) play a key role in climate change and air quality. Determining the fundamental parameters that distribute organic compounds between the phases is essential, as atmospheric lifetime and impacts change drastically ...
G. I. Gkatzelis, T. Hohaus, R. Tillmann, I. Gensch, M. Müller, M. Müller, P. Eichler, P. Eichler, K.-M. Xu, P. Schlag, P. Schlag, S. H. Schmitt, Z. Yu, R. Wegener, M. Kaminski, R. Holzinger, A. Wisthaler, A. Wisthaler, A. Kiendler-Scharr   +18 more
doaj   +1 more source

Revealing the Ion Chemistry Occurring in High Kinetic Energy-Ion Mobility Spectrometry: A Proof of Principle Study

Analytica, 2023
Here, we present proof of principle studies to demonstrate how the product ions associated with the ion mobility peaks obtained from a High Kinetic Energy-Ion Mobility Spectrometer (HiKE-IMS) measurement of a volatile can be identified using a Proton ...
Florentin Weiss, Christoph Schaefer, Stefan Zimmermann, Tilmann D. Märk, Chris A. Mayhew   +4 more
doaj   +1 more source

Observation of Secondary Organic Aerosol and New Particle Formation at a Remote Site in Baengnyeong Island, Korea

Asian Journal of Atmospheric Environment, 2017
To improve the understanding of secondary organic aerosol (SOA) formation from the photo-oxidation of anthropogenic and biogenic precursors at the regional background station on Baengnyeong Island, Korea, gas phase and aerosol chemistries were ...
Jinsoo Choi , Yongjoo Choi, Junyoung Ahn , Jinsoo Park , Jun Oh , Gangwoong Lee, Taehyun Park, Gyutae Park, Jeffrey S. Owen, Taehyoung Lee   +9 more
doaj   +1 more source