Quantitative carbon-13 and proton nuclear magnetic resonance spectroscopy of crude oil and petroleum products. 2. Average structure parameters of representative samples

Molecular Structure and Intermolecular Interaction of Asphaltenes by FT-IR, NMR, EPR

“…The assumption that the molar ratio R is equal to the ratio between the number of CH 2 and CH 3 groups in the average side chains was used in equation (12). In Table 2 n IR values are reported and they are in good agreement with the n values obtained from NMR (Table 4).…”

“…An average number of carbon per alkyl side-chain (n IR ) can be now evaluated: (12) where R was defined in equation (1). The assumption that the molar ratio R is equal to the ratio between the number of CH 2 and CH 3 groups in the average side chains was used in equation (12).…”

Analysis of Model Fuels and Their Compatibility with Selected Elastomers. Part 1

“…Fourier transform broad-band multinuclear instrument, operated according to the procedures of Gillet, Rubini, Delpuech, et al (12) Deuterochloroform, CDCI 3 , was used as the solvent, p-dioxane was the internal standard, and ferric acetylacetonate (Fe(acac) 3 ) served as the relaxation agent in the 1 3 C experiments. In addition to developing interpretation of the NMR spectra according to the method of Gillet, et al, an aiternati;!e interpretation of the same spectra, according to the recommendations of Bailey and co-workers (13,14) is also offered.…”

The Use of 13C NMR Spectroscopy and Comprehensive Two-dimensional Gas Chromatography, GC×GC, for Identification of Compounds Involved in Diesel Fuel Oxidative Behavior

“…NMR spectroscopy has proven useful to determine total carbon to proton ratio and to characterize fuels providing information on naphthenic, normal and isoparaffin as well as mono and poliaromatic compound contents. [2][3][4][5][6][7][8] Average chain lengths of normal and isoparaffins can be obtained too. 9,10 Comprehensive two dimensional GC×GC is an analytical technique which provides powerful multidimensional separation and detection of low concentrations of normal paraffins in insoluble sediments.…”