Results 1 to 10 of about 27,664 (259)

Recovery of Odorants from an Olfactometer Measured by Proton-Transfer-Reaction Mass Spectrometry [PDF]

Sensors, 2013
The aim of the present study was to examine the recovery of odorants during the dilution in an olfactometer designed according to the European standard for dynamic olfactometry.
Anders Feilberg, Michael Jørgen Hansen, Anders Peter S. Adamsen   +2 more
doaj   +4 more sources

Identifying volatile in vitro biomarkers for oral bacteria with proton-transfer-reaction mass spectrometry and gas chromatography–mass spectrometry [PDF]

Scientific Reports, 2021
We have measured the volatile fingerprints of four pathogenic oral bacteria connected to periodontal disease and dental abscess: Porphyromonas gingivalis (three separate strains), Prevotella intermedia, Prevotella nigrescens and Tannerella forsythia ...
Kajsa Roslund, Markku Lehto, Pirkko Pussinen, Kari Hartonen, Per-Henrik Groop, Lauri Halonen, Markus Metsälä   +6 more
doaj   +2 more sources

Breath profiles in paediatric allergic asthma by proton transfer reaction mass spectrometry [PDF]

BMJ Open Respiratory Research
Introduction Enhancing paediatric asthma diagnosis is crucial. Molecular analysis of exhaled breath is a rapidly evolving field aimed at harnessing established and innovative technologies for clinical applications. This study evaluates the feasibility of
Alexander Moeller, Lamkaddam Houssni, Micic Srdjan, Bruderer Tobias, Baumann Yvette, Di Francesco Fabio, Koch Patricia, Lomonaco Tommaso, Prévôt André, Prince Tiwari, Reale Serena, Ripszam Matyas, Weber Ronja, Imad El Haddad   +13 more
doaj   +2 more sources

Proton transfer reaction mass spectrometry: A green alternative for food volatilome profiling

Green Analytical Chemistry, 2022
Proton transfer reaction mass spectrometry (PTR-MS) has been developed for the direct, high sensitivity and high time resolution monitoring of volatile organic compounds (VOCs).
Maria Mazzucotelli, Brian Farneti, Iuliia Khomenko, Karina Gonzalez-Estanol, Michele Pedrotti, Mariagiovanna Fragasso, Vittorio Capozzi, Franco Biasioli   +7 more
doaj   +5 more sources

Evaluation of Terpene Decomposition in Kaffir Lime Juice during Storage Using Gas Chromatography–Mass Spectrometry and Proton Transfer Reaction–Mass Spectrometry [PDF]

Molecules
Kaffir lime juice, often treated as production waste, can be a good source of terpenes. These compounds undergo various decomposition processes under the influence of external factors, especially during transportation and storage.
Martyna Lubinska-Szczygeł, Żaneta Polkowska, Blanka Tobolkova, Tomasz Majchrzak, Martin Polovka, Parichart Promchote, Shela Gorinstein   +6 more
doaj   +2 more sources

Advances in the application of proton transfer reaction mass spectrometry [PDF]

E3S Web of Conferences
With the continuous development of social science and technology, micro-area information has become an important part of modern material information research, environmental scanning electron microscope (ESEM) is a new type of scanning electron microscope
Li Zhengpei
doaj   +2 more sources

Measurement of alkyl and multifunctional organic nitrates by proton-transfer-reaction mass spectrometry [PDF]

Atmospheric Measurement Techniques, 2017
A commercial PTR-TOF-MS has been optimized in order to allow the measurement of individual organic nitrates in the atmosphere. This has been accomplished by shifting the distribution between different ionizing analytes, H3O+∕ H3O+(H2O)n or NO+∕ NO2+. The
M. Duncianu, M. David, S. Kartigueyane, M. Cirtog, J.-F. Doussin, B. Picquet-Varrault   +5 more
doaj   +6 more sources

Hydroxyl transfer versus cyclization reaction in the gas phase: Sequential loss of NH3 and CH2CO from protonated phenylalanine derivatives

Frontiers in Chemistry, 2023
Collisional activation of protonated phenylalanine derivatives deamination products leads to hydroxyl skeletal rearrangement versus cyclization reaction, and to form hydroxylbenzyl cation via elimination of CH2CO.
Mingyu Zheng, Xiaoping Zhang, Yihao Cheng, Lili Sun, Xinglei Zhang   +4 more
doaj   +1 more source

OH clock determination by proton transfer reaction mass spectrometry at an environmental chamber [PDF]

Atmospheric Measurement Techniques, 2012
The hydroxyl free radical (OH) is the major oxidizing species in the lower atmosphere. Measuring the OH concentration is generally difficult and involves elaborate, expensive, custom-made experimental setups.
P. Barmet, J. Dommen, P. F. DeCarlo, T. Tritscher, A. P. Praplan, S. M. Platt, A. S. H. Prévôt, N. M. Donahue, U. Baltensperger   +8 more
doaj   +1 more source

Formaldehyde measurements by Proton transfer reaction – Mass Spectrometry (PTR-MS): correction for humidity effects [PDF]

Atmospheric Measurement Techniques, 2010
Formaldehyde measurements can provide useful information about photochemical activity in ambient air, given that HCHO is formed via numerous oxidation processes.
A. Vlasenko, A .M. Macdonald, S. J. Sjostedt, J. P. D. Abbatt   +3 more
doaj   +1 more source