Abstract

Both an advantage and a limitation of current nuclear magnetic resonance techniques is the sensitivity of relaxation times to various chemical and physical environmental conditions. Thus accurate determination of flow is foiled by the similar order of magnetude sensitivity of relaxation measurements to molecular oxygen concentrations. Resolution of the ambigarty that results would occur if it were possible to perform measurements far more sensitive to molecular environment effects and less so to physical factors. Unpaired electrons and spectra that can be gathered from them electron spin responce spectra - fulfill this criterion. Not only do they allow resolution of ambiguities from high spatial resolution nuclear magnetic resonance scans but promise chemically and physiologically interesting measurements in and of themselves.

© 1984 Optical Society of America