Abstract
Nuclear Magnetic Resonance Imaging has rapidly advanced since the first imaging experiments were performed in 1973. Today high quality liquids images are routinely formed for non invasive medical diagnosis. At present solids imaging lags far behind liquids imaging in terms of image quality. This is primarily due to the technical difficulty in imaging very broad linewidths inherent for solids. Since the mid 1980's a vast range of diverse and ingenious solids imaging techniques have been invented. This thesis represents work in one of the most promising lines of research for solids imaging; multiple pulse line narrowing. The research was performed on a 30 MHz Magnex Scientific Ltd superconducting magnet, magnetic field gradient set and three Vechron 7780 amplifiers. This equipment replaced the existing Varian Electromagnet and amplifiers. A large portion of the work in interfacing and programming the multiple pulse sequences with the homebuilt spectrometer of Dr P. J. McDonald is not described. Only the most important experiments and calculations were included for coherence and brevity The reader is brought on a clear route through the thesis: The fundamentals of NMR is described followed by the theory and analysis of the zig zag 6 pulse imaging sequence. It is theoretically shown that a more efficient sequence can be made from 4 sub cycles of the zig zag sequence with blipped gradients. The sequence is implemented and images shown from chapter 5. A new Patented 2DFT imaging technique is implemented and demonstrated. It is compared to three other techniques. An analysis of gradient amplifier properties, eddy currents and the manufacture of a new commercial high field actively shielded gradient set is described. The quantitive analysis of water mobility in zeolite A using multiple pulse imaging techniques to illucidate structure is described. Conclusions of the research and success of multiple pulse NMR are given. Future experiments are suggested.