scholarly journals Internal Versus External Sources of Plasma at Saturn: Overview From Magnetospheric Imaging Investigation/Charge-Energy-Mass Spectrometer Data

2018 ◽  
Vol 123 (6) ◽  
pp. 4712-4727 ◽  
Author(s):  
R. C. Allen ◽  
D. G. Mitchell ◽  
C. P. Paranicas ◽  
D. C. Hamilton ◽  
G. Clark ◽  
...  
Keyword(s):  
Mass Spectrometer ◽  
Charge Energy ◽  
External Sources ◽  
Spectrometer Data

scholarly journals In-Situ Chemical and Isotopic Measurements of the Atmosphere of Jupiter

1998 ◽  
Vol 11 (2) ◽  
pp. 1057-1064
Author(s):  
P.R. Mahaffy ◽  
S.K. Atreya ◽  
H.B. Niemann ◽  
T.C. Owen
Keyword(s):  
Mass Spectrometer ◽  
Atmospheric Composition ◽  
Mixing Ratios ◽  
Major Species ◽  
Lateral Mixing ◽  
Detailed Composition ◽  
Different Depths ◽  
Galileo Probe ◽  
Spectrometer Data

AbstractInsights into both the detailed composition of Jupiter’s atmosphere and unexpected local meteorological phenomena were revealed by in-situ measurements from the Galileo Probe Neutral Mass Spectrometer taken on December 7, 1995. Measurements of the neutral atmospheric composition from a pressure of 0.5 bar to approximately 21 bar revealed the mixing ratios of the major species helium and hydrogen as well as numerous minor constituents including methane, water, ammonia, ethane, ethylene, propane, hydrogen sulfide, neon, argon, krypton, and xenon. This instrument measured the isotope ratios3He/4He, D/H, and13C/12C as well as the isotopes of neon, argon, krypton, and xenon. A summary is given of progress that has been made in refining preliminary estimates of the abundances of condensable volatiles and noble gases as a result of an ongoing laboratory study using a nearly identical engineering unit. The depletion of simple condensable species to depths well below their expected condensation levels is explained by a local downdraft in the region of the probe entry. The mass spectrometer data suggests that different species may recover at different depths and this may be due to lateral mixing of Jovian air.

A Method for Estimating Mass-Transfer Coefficients in a Biofilter from Membrane Inlet Mass Spectrometer Data

2009 ◽  
Vol 59 (2) ◽  
pp. 155-162 ◽  
Author(s):  
Anders Michael Nielsen ◽  
Lars Peter Nielsen ◽  
Anders Feilberg ◽  
Knud Villy Christensen
Keyword(s):  
Mass Transfer ◽  
Mass Spectrometer ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Spectrometer Data

Separation and Characterization of Amine Drugs and Their Enantiomers by Capillary Column Gas Chromatography-Mass Spectrometry

1983 ◽  
Vol 66 (6) ◽  
pp. 1443-1446
Author(s):  
Ray H Liu ◽  
Warren W Ku ◽  
Mary P Fitzgerald
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Mass Spectrometer ◽  
Capillary Column ◽  
Gas Chromatography Mass Spectrometry ◽  
Gas Chromatograph ◽  
Capillary Column Gas Chromatography ◽  
Spectrometer Data ◽  
Amine Drug

Abstract A gas chromatograph-mass spectrometer-data system equipped with a capillary column is used to analyze commonly abused amine drug mixtures. Enantiomeric amines are analyzed as N-trifluoroacetyl- I-prolyl chloride derivatives. The 10 compounds included in this study are amphetamine, methamphetamine, norephedrine, ephedrine, 3,-4-methylenedioxyamphetamine, N,N-dimethyltryptamine, N,N-diethyltryptamine, N,N-dimethyl-5-methoxytryptamine, mescaline, and caffeine. All compounds, including possible enantiomers, are resolved and identified by the described method.

Parsing and Quantification of Raw Orbitrap Mass Spectrometer Data Using RawQuant

2018 ◽  
Vol 17 (6) ◽  
pp. 2237-2247 ◽  
Author(s):  
Kevin A. Kovalchik ◽  
Sophie Moggridge ◽  
David D. Y. Chen ◽  
Gregg B. Morin ◽  
Christopher S. Hughes
Keyword(s):  
Mass Spectrometer ◽  
Orbitrap Mass Spectrometer ◽  
Spectrometer Data

scholarly journals Elemental analysis of chamber organic aerosol using an aerodyne high-resolution aerosol mass spectrometer

2010 ◽  
Vol 10 (9) ◽  
pp. 4111-4131 ◽  
Author(s):  
P. S. Chhabra ◽  
R. C. Flagan ◽  
J. H. Seinfeld
Keyword(s):  
High Resolution ◽  
Elemental Composition ◽  
Mass Spectrometer ◽  
Organic Aerosol ◽  
Uptake System ◽  
Aerosol Mass Spectrometer ◽  
Aerosol Mass ◽  
Single Ring ◽  
Spectrometer Data ◽  
Ambient Measurements

Abstract. The elemental composition of laboratory chamber secondary organic aerosol (SOA) from glyoxal uptake, α-pinene ozonolysis, isoprene photooxidation, single-ring aromatic photooxidation, and naphthalene photooxidation is evaluated using Aerodyne high-resolution time-of-flight mass spectrometer data. SOA O/C ratios range from 1.13 for glyoxal uptake experiments to 0.30–0.43 for α-pinene ozonolysis. The elemental composition of α-pinene and naphthalene SOA is also confirmed by offline mass spectrometry. The fraction of organic signal at m/z 44 is generally a good measure of SOA oxygenation for α-pinene/O3, isoprene/high-NOx, and naphthalene SOA systems. The agreement between measured and estimated O/C ratios tends to get closer as the fraction of organic signal at m/z 44 increases. This is in contrast to the glyoxal uptake system, in which m/z 44 substantially underpredicts O/C. Although chamber SOA has generally been considered less oxygenated than ambient SOA, single-ring aromatic- and naphthalene-derived SOA can reach O/C ratios upward of 0.7, well within the range of ambient PMF component OOA, though still not as high as some ambient measurements. The spectra of aromatic and isoprene-high-NOx SOA resemble that of OOA, but the spectrum of glyoxal uptake does not resemble that of any ambient organic aerosol PMF component.

scholarly journals Receptor modeling of near-roadway aerosol mass spectrometer data in Las Vegas, Nevada, with EPA PMF

2011 ◽  
Vol 11 (8) ◽  
pp. 22909-22950 ◽  
Author(s):  
S. G. Brown ◽  
T. Lee ◽  
G. A. Norris ◽  
P. T. Roberts ◽  
J. L. Collett ◽  
...  
Keyword(s):  
Mass Spectrometer ◽  
Las Vegas ◽  
Organic Aerosol ◽  
Receptor Modeling ◽  
Factor Solution ◽  
Aerosol Mass Spectrometer ◽  
Source Profiles ◽  
Aerosol Mass ◽  
The Us ◽  
Spectrometer Data

Abstract. Ambient non-refractory PM1 aerosol particles were measured with an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-AMS) at an elementary school 20 m from the US 95 freeway in Las Vegas, Nevada, during January 2008. Additional collocated continuous measurements of black carbon (BC), carbon monoxide (CO), nitrogen oxides (NOx), and meteorological data were collected. The US Environmental Protection Agency's (EPA) positive matrix factorization (PMF) data analysis tool was used to apportion organic matter (OM) as measured by HR-AMS, and rotational tools in EPA PMF were used to better characterize the solution space and pull resolved factors toward known source profiles. Three- to six-factor solutions were resolved. The four-factor solution was the most interpretable, with the typical AMS PMF factors of hydrocarbon-like organic aerosol (HOA), low-volatility oxygenated organic aerosol (LV-OOA), biomass burning organic aerosol (BBOA), and semi-volatile oxygenated organic aerosol (SV-OOA). When the measurement site was downwind of the freeway, HOA composed about half the OM, with SV-OOA and LV-OOA accounting for the rest. Attempts to pull the PMF factor profiles toward source profiles were successful but did not qualitatively change the results, indicating that these factors are very stable. Oblique edges were present in G-space plots, suggesting that the obtained rotation may not be the most plausible one. Since solutions found by pulling the profiles or using Fpeak retained these oblique edges, there appears to be little rotational freedom in the base solution. On average, HOA made up 26 % of the OM, and it made up nearly half of the OM when the monitoring site was downwind of US 95 during morning rush hour. LV-OOA was highest in the afternoon and accounted for 26 % of the OM. BBOA occurred in the evening hours, was predominantly from the residential area to the north, and on average constituted 12 % of the OM; SV-OOA accounted for the remaining third of the OM. Use of the pulling techniques available in EPA PMF and ME-2 suggested that the four-factor solution was very stable.

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