Figure 3 shows the relative abundance of the basic classes identified from the positive-ion ESI FT-ICR mass spectra
of four samples of shale oil at a heating rate of 5-20 [degrees]C [min.
Recent advances in mass spectrometry have facilitated the routine acquisition of mass spectra
at high resolution with sufficient resolution and peak capacity to handle the complexity of the mixture with only a single dimension of chromatographic separation.
cereus) and served as an internal standard allowing comparison between mass spectra
in this study and previous ones.
were obtained scanning in the range m/z 600-900.
Fast atom bombardment (FAB) mass spectra
of each of the trinuclear 4,4'-bipyridine complexes as acetonitrile solutions display a distinctive set of ions with masses corresponding to the series [[Cr.
and LRI were obtained for identification, and external standards were used for quantification.
The mass spectra
of the only characterized alkaloids ([M.
The software's ability to deconvolve mass spectra
in the presence of high noise levels and co-elutants permits the use of extremely short and simple GC temperature programmes, and virtually eliminates the need for extensive sample clean-up or lengthy separations prior to MS detection.
Figure 2 shows four ESI mass spectra
of polyethylene glycol (PEG) samples with increasing average molecular weight.
Both dimethyldichlorosilane and trifluoroacetic anhydride gave distinctive mass spectra
with both molecular and fragment ions that were suitable for selected ion monitoring of 9-hydroxyphenanthrene at trace levels.
This gives good mass spectra
with the advantage that the spectrum is the same at all points on the target, that is, "sweet spots" (defined as regions giving especially strong analyte signal) are eliminated.
for NA were registered in SCAN and SIM modes.