ISSN:
0030-493X
Schlagwort(e):
Chemistry
;
Analytical Chemistry and Spectroscopy
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The individual steps of the consecutive reactions arising from metastable molecular ions, derived from vitamin D3, vitamin D2 and their respective provitamins (7-dehydrocholesterol, ergosterol), were examined in different field-free regions of a triple-sector mass spectrometer of B/E/E geometry. The comparison of the translational energy release (T) and the metastable peak shapes corresponding to these reactions, as well as unimolecular and collision-induced dissociation mass-analysed ion kinetic energy spectra, showed that there are probably two structures of the [M - H2O]+· and [M - CH3·]+ ions depending upon whether the respective ions are formed in the ion source through high-energy reactions, or from the fragmentation of metastable molecular ions through slow, low-energy processes which occur in the first field-free region.
Zusätzliches Material:
3 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/oms.1210221008
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