Using Nuclear Magnetic Resonance and the Dipolar Field to Study Structural Properties of Two-Phase Liquid Systems

摘要

Nuclear Magnetic Resonance (NMR) is a convenient and noninvasive means for studying the internal structure of diamagnetic substances. The extraction of length scale information in liquid NMR spectroscopy is largely limited to sizes below the diffusion length ((caret) 50 microns). Breaking translational symmetry using the nuclear dipolar field imparts a scale dependence, and provides a means of measuring length scales above this limit. The use of the dipolar field in liquid NMR to make structural measurements is a relatively novel concept in the field, and previous techniques have been largely limited to test cases. This thesis examines the extraction of length-scale information from a relatively complex two-phase liquid system, specifically a poly-disperse oil/water emulsion. Theory is developed and then compared to experimental results, with good agreement. Simple scaling laws are identified which provide a simple means of using the technique for length scale measurements. The thesis then focuses on developing the theory and feasibility of using the developed dipolar NMR technique to study flowing systems, in order to extract average length scale and interfacial properties, including interfacial velocity and interfacial area.