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Flash desorption mass spectrometry

Prior to 1970 our understanding of the bonding of diatomic molecules to surfaces, and in many cases the type of adsorption (i.e., molecular or dissociative) was almost entirely dependent on indirect experimental evidence. By this we mean that deductions were made on the basis of data obtained from monitoring the gas phase whether in the context of kinetic studies based on gas uptake or flash desorption, mass spectrometry, or isotopic exchange. The exception was the important information that had accrued from infrared studies of mainly adsorbed carbon monoxide, a molecule that lent itself very well to this approach owing to its comparatively large extinction coefficient. [Pg.65]

Analytical pyrolysis is defined as the characterization of a material or a chemical process by the instrumental analysis of its pyrolysis products (Ericsson and Lattimer, 1989). The most important analytical pyrolysis methods widely applied to environmental samples are Curie-point (flash) pyrolysis combined with electron impact (El) ionization gas chromatography/mass spectrometry (Cp Py-GC/MS) and pyrolysis-field ionization mass spectrometry (Py-FIMS). In contrast to the fragmenting El ionization, soft ionization methods, such as field ionization (FI) and field desorption (FD) each in combination with MS, result in the formation of molecule ions either without, or with only very low, fragmentation (Lehmann and Schulten, 1976 Schulten, 1987 Schulten and Leinweber, 1996 Schulten et al., 1998). The molecule ions are potentially similar to the original sample, which makes these methods particularly suitable to the investigation of complex environmental samples of unknown composition. [Pg.540]


See other pages where Flash desorption mass spectrometry is mentioned: [Pg.695]    [Pg.168]    [Pg.168]    [Pg.444]    [Pg.46]    [Pg.43]    [Pg.229]    [Pg.270]    [Pg.176]    [Pg.162]    [Pg.598]    [Pg.399]   
See also in sourсe #XX -- [ Pg.42 ]




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