scholarly journals An approach to estimate the activation energies of fragmentation occurring in quadrupole collision cell of the mass spectrometer

2017 ◽  
Vol 52 (10) ◽  
pp. 672-680 ◽  
Author(s):  
Ákos Kuki ◽  
Lajos Nagy ◽  
Miklós Zsuga ◽  
Sándor Kéki
Keyword(s):  
Mass Spectrometer ◽  
Activation Energies ◽  
Collision Cell ◽  
Quadrupole Collision Cell

Reactive collisions in quadrupole cells. 6. H/D exchange reactions of protonated alkylbenzenes with D2O, CH3OD, and C2H5OD

1995 ◽  
Vol 73 (11) ◽  
pp. 1779-1784 ◽  
Author(s):  
Jinsong Ni ◽  
Alex. G. Harrison
Keyword(s):  
Mass Spectrometer ◽  
Alkyl Group ◽  
Collision Cell ◽  
Tandem Mass ◽  
Exchange Reactions ◽  
Deuterium Incorporation ◽  
Tandem Mass Spectrometer ◽  
Quadrupole Collision Cell ◽  
Reactive Collisions

The H/D exchange reactions occurring on collision of protonated alkylbenzenes with C2H5OD, CH3OD, and D2O at low collision energies in the quadrupole collision cell of a hybrid tandem mass spectrometer have been studied for 22 alkylbenzenes. The exchange reactions with D2O are much less efficient than the exchange reactions with C2H5OD or CH3OD; this difference is rationalized on energetics grounds. The H/D exchange of the protonated alkylbenzenes with C2H5OD or CH3OD leads, typically, to 40–70% deuterium incorporation in the protonated alkylbenzene and, for most cases, to significant ion signals corresponding to exchange of the added hydrogen and the aromatic hydrogens. Thus, the method is a feasible approach to counting the number of aromatic hydrogens in alkylbenzenes. The extent of exchange decreases with increasing size of the alkyl group in monoalkylbenzenes for reasons that are not readily understood. Keywords: protonated alkylbenzenes, H/D exchange, reactive collisions.

THE INTERACTIONS OF NITROGEN AND CARBON MONOXIDE ON POLYCRYSTALLINE TUNGSTEN

1964 ◽  
Vol 42 (6) ◽  
pp. 1256-1269 ◽  
Author(s):  
L. J. Rigby
Keyword(s):  
Carbon Monoxide ◽  
Mass Spectrometer ◽  
Tungsten Wire ◽  
Activation Energies ◽  
Β Phase ◽  
Polycrystalline Tungsten

Desorption spectra from a polycrystalline tungsten wire have been obtained with a mass spectrometer to study: (a) the effect of preadsorbed nitrogen on the adsorption of carbon monoxide; (b) the reversibility and rearrangement of the carbon monoxide monolayer; and (c) the slow replacement of carbon monoxide by nitrogen. Surface coverages have been measured, and the activation energies of desorption obtained for all phases of carbon monoxide and the β phase of nitrogen.

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