Page 223 - Tandem Techniques
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It is seen that the two spectroscopic techniques can be used in a complimentary fashion to identify the
very small samples that frequently arise in pollution and environmental studies.
Another source of pollution involving aromatic material is the adsorption of polycyclic hydrocarbons
from car exhaust and other sources onto street dust. Yang and Baumann [27] developed an analytical
method, involving a GC/MS tandem combination for this purpose. The samples were collected form
various sites through out Germany, and were subjected to liquid carbon dioxide extraction's followed by
expansion and deposition in a series of short RP 18 columns [28]. The contents of each column could
be individually selected and passed to the GC/MS instrument. A Hewlett-Packard 5890A gas
chromatograph and a Hewlett-Packard 5970 mass spectrometer were employed for the analysis.
Figure 5.27
Chromatogram of a Dust Sample Extract (ref. 27)
The column was 50 m long, 250 µm I.D. and the separation was selective ion monitored. An example of
a chromatogram obtained by selective ion
