Abstract
Although some of the first magnetic resonance imaging (MRI) experiments involved the imaging of solids, the progress of broadline (solid state) MRI has not followed as rapidly as that of its liquid state counterpart. The lack of progress to date has been due to the short spin spin relaxation times found in solid materials, which are typically of the order of microseconds as opposed to the seconds found in liquids. The fast relaxation rates mean that the relatively weak magnetic field gradients which are used extensively in liquid state MRI can no longer be utilised. In addition to solid materials, liquids in confined environments also exhibit shortened spin spin relaxation times. Thus the development of broadline MRI is necessary for the study of both solid systems and the behaviour of liquids within porous media. In recent years solid state MRI has been the focus of increasing interest as new technology and methods have been devised to combat the problems encountered in the imaging of solid materials. This thesis begins by reviewing several of the techniques commonly used for solid state MRI experiments. In Chapters 3 and 4 original theoretical work conducted on improvements to the broadline gradient and spin echo imaging techniques is then presented. This is followed in Chapter 5 by a theoretical analysis of the use of solid echo sequences in the extremely high magnetic field gradients found at the edge of superconducting magnets and in Chapter 6 by the investigation of a new pulse sequence for stray field imaging. In each case experimental work has been conducted to verify the theoretical predictions. Finally, an illustration of some of the practical applications of broadline MRI using the aforementioned techniques is given in Chapter 7.