id	author	title	date	pages	extension	mime	words	sentence	flesch	summary	cache	txt
cet-2331	Arenas-Diaz, J.P.; Palacio Lozano, D.C.; Ramirez, X.; Cabanzo, R.; Guzman, A.; Mejia-Ospino, E.	Chemical Characterization of Polar Species in Colombian Vacuum Residue and Its Supercritical Fluid Extraction Subfractions Using Electrospray Ionization FT-ICR Mass Spectrometry	2017	6	.pdf	application/pdf	2995	119	45	It is known that the type of nitrogen compounds contained in petroleum samples is important due to the participation of these species in deactivation of catalysts used in hydrotreatment processes (Furimsky et al., 1999). Figure 1: Heteroatom class distribution for vacuum residue and its subfractions from positive-mode ESI FT- ICR MS Negative-mode ESI FT-ICR offers a selectively ionization of acid compounds and non-basic nitrogen compounds.	cache/cet-2331.pdf	txt/cet-2331.txt