Effect of sample age of fluorocarbons on MC800 asphaltene on dynamic nuclear polarization parameters

Abstract

Nuclear Magnetic Resonance and Overhauser effect type dynamic nuclear polarization (DNP) experiments were performed to study suspensions of asphaltene in the fluorocarbons at a low magnetic field of 1.53 mT at room temperature. Asphaltene was extracted from MC800 liquid asphalt, which was Heavy Iran origin. Each sample of the solvent medium was produced at three different concentrations of asphaltene. These samples were kept for a period of seven years until DNP parameters were discovered through new DNP tests. The influence of sample age on parameters of DNP was studied and then the findings were analyzed. It was found that the  nuclear-electron coupling parameter was smaller. In low magnetic fields the nuclear-electron coupling parameter. varies from +0.5 (pure dipolar) to -1.0 (pure scalar), and new  obtained values are between these limits. New  values in our study are positive and this shows that the dipolar part of intermolecular spin-spin interactions is dominant.