Pyrolysis product list, molecular mass (M+), fragment ions used for quantification and retention times relative to guaiacol (RT) code Name [M.sup.+] mass 10:1-28:1 C10-28 alkene 140-392 55+69 10:0-28:0 C10-28 alkane 142-394 57+71 Al1 aliphatic compound n.d.
Aliphatic compounds like alkane and alkene compounds carbon chain start from small to long chain hydrocarbon showing in this fuel is [C.sub.4]-[C.sub.28].
They represent different classes of compounds such as alkaloids, diterpenoid lactones, phenolics and their glycosides, sesquiterpenoids, steroids, aliphatic compounds and polysaccharides (for review Singh et al., 2003).
For instance, polar fractions high in quinones were much more potent in inducing cell death, whereas aromatic compounds high in PAHs had a more moderate effect, and aliphatic compounds had no apparent effect.
Considering the results of fractional composition (Table 4) and SRATR FTIR spectroscopy we can conclude that HA isolated from the same soil type under grassland management contained more newly formed aliphatic compounds and less aromatic compound in their molecule.