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Atmospheric-pressure-ionization mass spectrometry
TrAC Trends in Analytical Chemistry, 1994Mass spectrometer ion sources are normally located inside a high-vacuum envelope. An ion source operating at atmospheric pressure is better suited, it not essential, for a growing number of applications. MS analysis of samples pyrolyzed under controlled conditions makes use of chemical ionization at atmospheric pressure. On-line LC-MS which employs the
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Atmospheric pressure ionization mass spectrometry
Journal of Chromatography A, 1977The analytical system described here consists of a gas chromatograph, an atmospheric pressure ionization mass spectrometer designed for operation in the negative ion mode, and a computer. The gas stream from the gas chromatograph is split in order to obtain concurrent but separate detection with a standard electron capture detector and with the mass ...
E.C. Horning +5 more
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Atmospheric ionization by precipitated electrons
Journal of Atmospheric and Terrestrial Physics, 1974Abstract A relatively simple procedure for the calculation of ionization production rate profiles due to precipitated electrons is described. It is used to show that the exospheric temperature can have an important effect on the production rates in the F-region and that the magnetic dip angle must be taken into account when calculating the profiles ...
Annemarie Wulff, J.A Gledhill
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Cosmic-ray Ionization in the Lower Atmosphere
Health Physics, 1987A high-pressure ion chamber filled with 2.5825 X 10(5) kg m-2 argon as used to measure the dose rates of several sites of interest in an attempt to evaluate the dose rates contributed by cosmic rays. Observation sites included two water reservoirs deeper than 110 m, Mount Ali which is higher than 2500 m, airliners flying at altitudes higher than 6700 m,
P S, Weng, C F, Chen
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Atmospheric pressure photoionization☆II. Dual source ionization
Journal of Chromatography A, 2004In this paper we describe results based on the combination of atmospheric pressure photoionization (APPI) with atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI). The main purpose of combining more than one ionizer is to extend the range of compounds that can be simultaneously analyzed.
Jack A, Syage +4 more
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Atmospheric‐pressure Penning ionization of aliphatic hydrocarbons
Rapid Communications in Mass Spectrometry, 2006Abstract A study has been made of the atmospheric‐pressure Penning ionization (APPeI) of aliphatic hydrocarbons (pentane, hexane, heptane, and octane) with long‐lived rare gas atoms (Rg*). The metastable rare gas atoms (He*, Ne*, Ar* and Kr*) were generated by the negative‐mode corona discharge of atmospheric ...
Kenzo, Hiraoka +5 more
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Atmospheric ionization and its variations
Proceedings of the Physical Society of London, 1924The atmospheric electricity elements dealt with include the potential gradient, the numbers of positive and negative ions and the charges carried by them, the conductivity of the air and the vertical air-earth current. For instantaneous values it suffices to know the potential gradient and either the conductivity or the current. But in the case of mean
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Super‐atmospheric pressure chemical ionization mass spectrometry
Journal of Mass Spectrometry, 2013Super‐atmospheric pressure chemical ionization (APCI) mass spectrometry was performed using a commercial mass spectrometer by pressurizing the ion source with compressed air up to 7 atm. Similar to typical APCI source, reactant ions in the experiment were generated with corona discharge using a needle electrode.
Lee Chuin, Chen +2 more
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Measuring atmospheric trace gases using mass spectrometry
Nature Reviews Earth & Environment, 2021Krystal T Vasquez
exaly