title: Phosphorus-31 studies on lecithin in ethanol solutions.
abstract: 31P relaxation times of lecithin in ethanol solutions have been measured in dependence on temperature and water concentration. Trial calculations have been carried out on the assumption of a 2-site exchange model. The results suggest first, the relaxation behaviour is determined by various motional and exchange processes; second, at 29 MHz the dipole-dipole interaction between 31P and protons provides the dominant contribution; third, in general we are not concerned with the case of "extreme narrowing". Morover, there are no negligible intermolecular contributions to relaxation.
mesh_terms: D002151:Calorimetry; D004578:Electron Spin Resonance Spectroscopy; D000431:Ethanol; D008968:Molecular Conformation; D010713:Phosphatidylcholines; D010759:Phosphorus Isotopes; D013816:Thermodynamics
chemical_list: D010713:Phosphatidylcholines; D010759:Phosphorus Isotopes; D000431:Ethanol