The effect of sample age on dynamic nuclear polarization parameters in asphalt suspensions

Abstract

The Overhauser effect type dynamic nuclear polarization was used to study some colloidal suspensions with benzene, toluene, ethylbenzene, mesitylene, tetralin, and chlorobenzene solvent media of asphaltene obtained from MC-30 liquid asphalt in a weak magnetic field of 1.437 mT at room temperature. For each sample of solvent medium, the samples were prepared in three different asphaltene concentrations. The samples were held for ten years and then dynamic nuclear polarization parameters were found via dynamic nuclear polarization experiments that were performed again. Thus, the effect of sample age to dynamic nuclear polarization parameters was investigated. The results were discussed.