Design and development of a new program for data processing of mass spectra acquired by means of a high-resolution double-focusing glow-discharge mass spectrometer

2001 ◽  
Vol 370 (5) ◽  
pp. 663-670 ◽  
Author(s):  
J. Robben ◽  
Davy Dufour ◽  
R. Gijbels
Keyword(s):  
High Resolution ◽  
Glow Discharge ◽  
Data Processing ◽  
Mass Spectrometer ◽  
Mass Spectra ◽  
Design And Development ◽  
Double Focusing

High speed acquisition and data processing of peaks in theB-E plane of a double focusing mass spectrometer

1981 ◽  
Vol 16 (11) ◽  
pp. 507-511 ◽  
Author(s):  
G. A. Warburton ◽  
R. S. Stradling ◽  
R. S. Mason ◽  
M. Farncombe
Keyword(s):  
Data Processing ◽  
Mass Spectrometer ◽  
High Speed ◽  
Double Focusing

scholarly journals Factor analysis of combined organic and inorganic aerosol mass spectra from high resolution aerosol mass spectrometer measurements

2012 ◽  
Vol 12 (5) ◽  
pp. 13299-13335
Author(s):  
Y. L. Sun ◽  
Q. Zhang ◽  
J. J. Schwab ◽  
T. Yang ◽  
N. L. Ng ◽  
...  
Keyword(s):  
High Resolution ◽  
Ammonium Nitrate ◽  
Mass Spectrometer ◽  
Mass Spectra ◽  
Organic Nitrates ◽  
Aerosol Mass Spectrometer ◽  
Inorganic Aerosols ◽  
Aerosol Mass ◽  
Inorganic Species ◽  
Mixing Characteristics

Abstract. The high resolution mass spectra of organic and inorganic aerosols from aerosol mass spectrometer (AMS) measurements were first combined into positive matrix factorization (PMF) analysis to investigate the sources and evolution processes of atmospheric aerosols. The new approach is able to study the mixing of organic aerosols (OA) and inorganic species, the acidity of OA factors, and the fragment ion patterns related to photochemical processing. In this study, PMF analysis of the unified AMS spectral matrices resolved 8 factors for the submicron aerosols measured at Queens College in New York City in summer 2009. The hydrocarbon-like OA (HOA) and cooking OA (COA) contain very minor inorganic species, indicating the different sources and mixing characteristics between primary OA and secondary species. The two factors that are primarily ammonium sulfate (SO4-OA) and ammonium nitrate (NO3-OA), respectively, are overall neutralized, of which the OA in SO4-OA shows the highest oxidation state (O/C = 0.69) among OA factors. The semi-volatile oxygenated OA comprises two components, i.e., a less oxidized (LO-OOA) and a more oxidized (MO-OOA). The MO-OOA represents a local photochemical product with the diurnal profile exhibiting a pronounced noon peak, consistent with those of formaldehyde (HCHO) and Ox (= O3+NO2). The much higher NO+/NO2+ fragment ion ratio in MO-OOA than that from ammonium nitrate alone provides evidence for the formation of organic nitrates. The amine-related nitrogen-enriched OA (NOA) contains ~25% of acidic inorganic salts, elucidating the formation of secondary OA from amines in acidic environments. The size distributions derived from 3-dimensional size-resolved mass spectra show distinct diurnal evolving behaviors for different OA factors, but overall a progressing evolution from smaller to larger particle mode as a function of oxidation states. Our results demonstrate that PMF analysis by incorporating inorganic aerosols is of importance for gaining more insights into the sources and processes, mixing characteristics, and acidity of OA.

scholarly journals Factor analysis of combined organic and inorganic aerosol mass spectra from high resolution aerosol mass spectrometer measurements

2012 ◽  
Vol 12 (18) ◽  
pp. 8537-8551 ◽  
Author(s):  
Y. L. Sun ◽  
Q. Zhang ◽  
J. J. Schwab ◽  
T. Yang ◽  
N. L. Ng ◽  
...  
Keyword(s):  
High Resolution ◽  
Ammonium Nitrate ◽  
Mass Spectrometer ◽  
Mass Spectra ◽  
Organic Aerosol ◽  
Organic Nitrates ◽  
Spectral Matrix ◽  
Aerosol Mass Spectrometer ◽  
Aerosol Mass ◽  
Inorganic Species

Abstract. Positive matrix factorization (PMF) was applied to the merged high resolution mass spectra of organic and inorganic aerosols from aerosol mass spectrometer (AMS) measurements to investigate the sources and evolution processes of submicron aerosols in New York City in summer 2009. This new approach is able to study the distribution of organic and inorganic species in different types of aerosols, the acidity of organic aerosol (OA) factors, and the fragment ion patterns related to photochemical processing. In this study, PMF analysis of the unified AMS spectral matrix resolved 8 factors. The hydrocarbon-like OA (HOA) and cooking OA (COA) factors contain negligible amounts of inorganic species. The two factors that are primarily ammonium sulfate (SO4-OA) and ammonium nitrate (NO3-OA), respectively, are overall neutralized. Among all OA factors the organic fraction of SO4-OA shows the highest degree of oxidation (O/C = 0.69). Two semi-volatile oxygenated OA (OOA) factors, i.e., a less oxidized (LO-OOA) and a more oxidized (MO-OOA), were also identified. MO-OOA represents local photochemical products with a diurnal profile exhibiting a pronounced noon peak, consistent with those of formaldehyde (HCHO) and Ox(= O3 + NO2). The NO+/NO2+ ion ratio in MO-OOA is much higher than that in NO3-OA and in pure ammonium nitrate, indicating the formation of organic nitrates. The nitrogen-enriched OA (NOA) factor contains ~25% of acidic inorganic salts, suggesting the formation of secondary OA via acid-base reactions of amines. The size distributions of OA factors derived from the size-resolved mass spectra show distinct diurnal evolving behaviors but overall a progressing evolution from smaller to larger particle mode as the oxidation degree of OA increases. Our results demonstrate that PMF analysis of the unified aerosol mass spectral matrix which contains both inorganic and organic aerosol signals may enable the deconvolution of more OA factors and gain more insights into the sources, processes, and chemical characteristics of OA in the atmosphere.

Increased Identification of Peptides by Enhanced Data Processing of High-Resolution MALDI TOF/TOF Mass Spectra Prior to Database Searching

2004 ◽  
Vol 76 (20) ◽  
pp. 6017-6028 ◽  
Author(s):  
Tomas Rejtar ◽  
Hsuan-shen Chen ◽  
Victor Andreev ◽  
Eugene Moskovets ◽  
Barry L. Karger
Keyword(s):  
High Resolution ◽  
Data Processing ◽  
Mass Spectra ◽  
Database Searching ◽  
Maldi Tof

Elastic scattering phenomena in mass analyzers with tandem fields

1970 ◽  
Vol 48 (14) ◽  
pp. 1735-1742 ◽  
Author(s):  
D. Ioanoviciu
Keyword(s):  
Elastic Scattering ◽  
Mass Spectrometer ◽  
Current Distribution ◽  
Mass Spectra ◽  
Ion Beam ◽  
Field Mass ◽  
Beam Path ◽  
Double Focusing

The elastic scattering in the tandem field mass analyzing systems is considered. The analysis includes deflecting electrostatic and magnetic converging, dispersing, diverging fields, and also the fields of quadrupoles. The influence of slits located on the ion beam path is indicated. An example illustrates the effect of slits on the elastically scattered current distribution in a double focusing mass spectrometer. Another example gives an idea about the influence of the diverging field on the peak tails in mass spectra.

The Decomposition of Benzene and Deuterated Benzenes under Electron Impact

1967 ◽  
Vol 22 (4) ◽  
pp. 454-459 ◽  
Author(s):  
K. R. Jennings
Keyword(s):  
Electron Impact ◽  
Mass Spectrometer ◽  
Mass Spectra ◽  
Charged Species ◽  
Decomposition Reactions ◽  
Fragment Ions ◽  
Double Focusing ◽  
Doubly Charged

Metastable transitions have been observed in the mass spectra of benzene, hexadeutero-benzene, 1,4-dideuterobenzene and 1,3,5-trideuterobenzene using a double-focusing mass spectrometer. Decomposition maps have been obtained for each substance and decomposition reactions leading to the production of all significant fragment ions have been suggested. Metastable transitions of several doubly-charged species were found. Loss if identity by the H and D atoms of the partly-deuterated benzenes was observed in metastable transitions in their mass spectra, indicating that rapid isomerization occurs before fragmentation.

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