Standard:

Not detected:

01: 	16:0	there is no MS/MS present
	17:0	not detected - only noise present
    
02: 	16:0	there is no MS/MS present

03: 	all are found


Biological:
In the biological sample, there are no MS/MS spectra for Cer_Na detectable.
Many FPs are caused by the unspecifity of Na. The small FA chain fragment increases
the specificity, but due the low abundance and high noise intensities cause quite often FPs.
A intensity rule with the PC_head wrong fragment deletes some FPs but also a species
in the standard sample.