Theses and Dissertations at Montana State University (MSU)
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Item Transient and steady state Rheo-NMR of shear banding wormlike micelles(Montana State University - Bozeman, College of Engineering, 2020) Al Kaby (Al Qayem), Rehab Noor; Chairperson, Graduate Committee: Sarah L. Codd and Jennifer Brown (co-chair); Jayesha S. Jayaratne, Timothy I. Brox, Sarah L. Codd, Joseph D. Seymour and Jennifer R. Brown were co-authors of the article, 'Rheo-NMR of transient and steady state shear banding under shear stratup' in the journal 'Journal of rheology' which is contained within this dissertation.; Sarah L. Codd, Joseph D. Seymour and Jennifer R. Brown were co-authors of the article, 'Characterization of velocity fluctuations and the transition from transient to steady state shear banding with and without pre-shear in a wormlike micelle solution under shear startup by Rheo-NMR' submitted to the journal 'Journal of applied rheology' which is contained within this dissertation.Over many years, the combination of nuclear magnetic resonance (NMR) techniques with rheometry, referred to as Rheo-NMR has been used to study materials under shear noninvasively. Rheo-NMR methods can provide valuable information on the rheological responses of materials or their behavior by temporally and spatially resolved mapping of the flow field. In this thesis, 1D velocity profiles across the fluid gap of a Couette shear cell are recorded using Rheo-NMR velocimetry to investigate the wormlike micelles (WLMs) surfactant system under transient and steady state flow conditions. The WLM system was a solution of 6 wt. % cetylpyridinium chloride (CPCl) and sodium salicylate (NaSal) in 0.5 M NaCl brine which is well-known for its ability to exhibit a mechanical response during flow known as shear banding. The shear banding phenomena is simply defined as the splitting of the flow into two macroscopic layers, a high and low shear band bearing different viscosities and local shear rates. Elastic instabilities are well known to develop in the unstable high shear band and manifest as fluctuations in the 1D measurements. Recently, it has been suggested that 1D velocimetry alone cannot reveal information about those observed fluctuations in terms of a sequence of elastic instabilities and 2D or 3D measurements are required. In this thesis, new Rheo-NMR equipment and quantitative analysis are used to characterize those fluctuations and show that 1D velocity measurements still have the potential to provide valuable information about 3D flows. Transient and steady state shear banding was observed for a range of shear rates across the stress plateau and the impact of several flow protocols were studied. The evolution of the high, low, and true shear rates, as well as interface position with time after shear startup was used to evaluate changes in the kinetics of shear band formation as a function of applied shear rate and flow protocol. Ultimately, these results will help in understanding the correlation between the macroscopic flow field and the microscopic structure and dynamics of WLMs and can also be a way to gain information about the presence and the dynamic of secondary flow without the need of a 3D measurement.Item Nuclear magnetic resonance studies to characterize phase transitions in porous systems(Montana State University - Bozeman, College of Engineering, 2018) Thrane, Linn Winsnes; Chairperson, Graduate Committee: Sarah L. Codd; Emily A. Berglund, James N. Wilking, David Vodak and Joseph D. Seymour were co-authors of the article, 'NMR relaxometry to characterize drug structural phase in a porous construct' in the journal 'Molecular pharmaceutics' which is contained within this thesis.; Sarah L. Codd and Joseph D. Seymour were co-authors of the article, 'Probing molecular dynamics during hydrate formation by high field NMR relaxometry and diffusometry' submitted to the journal 'Journal of magnetic resonance' which is contained within this thesis.; Ryanne L. Daily, Abby Thane, Catherine M. Kirkland, Evan R. McCarney, Robin Dykstra, Sarah L. Codd and Adrienne J. Phillips were co-authors of the article, 'Detecting microbially induced calcite precipitation in porous systems using low-field nuclear magnetic resonance relaxometry' submitted to the journal 'Environmental science & technology' which is contained within this thesis.Nuclear magnetic resonance (NMR) allows for in-situ non-invasive studies of a wide range of systems at microscopic time and length scales. NMR relaxometry and diffusometry techniques along with magnetic resonance imaging (MRI) are applied to explore and characterize various phase transitions in complex systems. NMR techniques are highly sensitive to the thermodynamic phase of the system as well as restrictions on molecular motion, and the ability to detect and monitor phase transitions non-invasively is of great interest for various industrial applications NMR frequency spectra and 1D T 2 relaxation measurements are used to characterize the presence of an amorphous drug and its liquid-solid phase transition. T 1- T 2 magnetic relaxation correlation experiments monitor the impact of long-time storage at high relative humidity on the drug in a porous silica tablet. The results indicate the ability of non-solid-state NMR to characterize crystalline and amorphous solid structural phases, and the potential for drug quality control by NMR methods. High resolution MRI along with T 1-T 2 magnetic relaxation correlation experiments and pulsed gradient stimulated echo (PGStE) NMR methods are demonstrated to characterize hydrate formation. MRI monitors the spatial heterogeneity of the system as well as local hydrate growth rates. Using T 1-T 2 correlation NMR and spectrally resolved diffusometry, the transition from mobile to restricted dynamics is observed simultaneously for both water and cyclopentane throughout the hydrate formation process. The combination of these MR techniques allows for exploration of the complex molecular dynamics involved in hydrate formation processes. Using a low-field NMR system, microbially induced calcite precipitation (MICP) processes in granular media are explored by means of 1D T 2 relaxation measurements. The 1D T 2 distributions allowed for in-situ monitoring of the mineral precipitation progress and indicates decrease in total pore volume and a significant change in the surface mineralogy of the granular media. The results confirm the potential for detailed characterization of MICP progression in engineering applications. Ultimately, NMR is demonstrated as an effective method for detecting, characterizing, and monitoring several distinct phase transitions at various time- and length-scales.Item Diffusion and diffusive exchange are sensitive to the structure of cartilage as measured by nuclear magnetic resonance(Montana State University - Bozeman, College of Engineering, 2017) Mailhiot, Sarah Elizabeth; Chairperson, Graduate Committee: Ronald K. June II; Nathan H. Williamson, Jennifer R. Brown, Joseph D. Seymour, Sarah L. Codd and Ronald K. June were co-authors of the article, 'T1-T2 correlation and biopolymer diffusion within human osteoarthritic cartilage measured with nuclear magnetic resonance' in the journal 'Applied magnetic resonance' which is contained within this thesis.; Sarah L. Codd, Jennifer R. Brown, Joseph D. Seymour and Ronald K. June were co-authors of the article, 'Pulsed gradient stimulated echo (PGSTE) NMR shows spatial dependence of fluid diffusion in human stage IV OA cartilage' submitted to the journal 'Magnetic resonance in medicine' which is contained within this thesis.; Fangrong Zong, James E. Maneval, Ronald K. June, Petrik Galvosas and Joseph D. Seymour were co-authors of the article, 'Quantifying NMR relaxation correlation and exchange in articular cartilage with time domain analysis' submitted to the journal 'Journal of magnetic resonance' which is contained within this thesis.; James E. Maneval, Ronald K. June and Joseph D. Seymour were co-authors of the article, 'Relaxation exchange in human OA cartilage impacts the observable T 2 relaxation rates' submitted to the journal 'Magnetic resonance in medicine' which is contained within this thesis.Osteoarthritis (OA) is the deterioration of the tissue on the surface of the articulating joints in mammals. OA is the progression loss of articular cartilage. OA affects 50% of people over age 65 and is the leading cause of workplace disability. There is no cure for OA and the state of the art treatment is joint replacement. One limitation for treating OA is the difficulty of diagnosing OA before tissue failure. Magnetic Resonance Imaging (MRI) is capable of detecting early pathologic changes to cartilage but challenges remain. The goal of this work is to evaluate how parameters, specifically relaxation and diffusion, used for creating imaging contrast in MRI are affected by disease in naturally occurring human osteoarthritis. Nuclear Magnetic Resonance (NMR) is utilized to measure the diffusion and magnetic relaxation in human OA cartilage samples. Diffusion Weighted Imaging (DWI) is a proposed imaging mechanism for diagnosing OA. The hypothesis is that fluid diffusion is faster in diseased tissue than in healthy tissue. We show that diffusion of fluid increases when cartilage is damaged by enzymes, such as during OA. We also show that the diffusion of fluid is donor specific in human OA cartilage. Diffusion of proteins in cartilage is also sensitive to enzyme degradation and donor as well as to the size and structure of the proteins in cartilage. These are complementary measures of the fluid and solid phase of cartilage. Relaxation weighted imaging is the most common way to image cartilage and is capable of measuring small structure changes due to OA. One limitation of this method is that reported relaxation rates vary between studies. We show that exchange, or motion of fluid, between the two sites of relaxation in cartilage alters the observed relaxation. Further, we show that the exchange rate is sensitive to donor and enzyme degradation. The results suggest that exchange rate is a sensitive measure of structure in cartilage and that relaxation should be cautiously interpreted when exchange occurs. Overall, this work shows that NMR and MRI are sensitive to the structure of cartilage and capable of detecting pathological damage to cartilage.Item NMR studies of supercritical CO 2 in carbon sequestration and immiscible two phase flow in porous media(Montana State University - Bozeman, College of Engineering, 2015) Prather, Cody Allen; Chairperson, Graduate Committee: Sarah L. CoddNuclear magnetic resonance (NMR) was used to research mechanisms related to two-phase flow in porous media. Experiments were conducted to further understand; 1) the capillary trapping mechanism that occurs during sequestration of CO 2 in deep underground sandstone reservoirs, 2) the viscous fingering phenomena that occurs when scCO 2 convectively dissolves in brine under reservoir conditions, and 3) flow patterns and fluid mechanisms in immiscible two-phase flow in porous media for the two pressure gradient regimes formed under different capillary numbers. Capillary trapping is a prominent mechanism for initially trapping CO 2 in pore structures of deep underground rock formations during the sequestration process. Because of its significant role in securing CO 2 underground, it is important to characterize and understand the residual saturation and distribution of CO 2 within the pore structure. A setup was developed in which drainage and imbibition of a Berea Sandstone core takes place within an NMR spectrometer under reservoir conditions. NMR results provide comparisons between the different nonwetting fluids used and help characterize the capillary trapping of each nonwetting fluid. In conclusion, scCO 2 is trapped 13% less efficiently than air or CO 2, and the nonwetting fluid is preferentially trapped in larger pores. Viscous fingering is a significant long-term trapping mechanism that further increases storage security by enhancing mass transfer through convective dissolution. A setup was developed in which scCO 2 could dissolve into a water saturated bead pack, under reservoir conditions, within the NMR spectrometer. NMR results track spatial changes in T 2 relaxation time and signal intensity. The results are inconclusive and the phenomena could not be directly observed but results do suggest dissolution is occurring during the experiment. Immiscible two-phase flow in porous media is unpredictable and existent in many industries. Therefore, determining flow patterns and understanding the fluid mechanisms from a capillary number/pressure gradient relationship could prove valuable. A setup was developed in which an immiscible two-phase flow through a bead pack was monitored, for different capillary numbers, with NMR techniques. NMR results provide snapshots of the water saturation distribution within the bead pack. The results suggest there's a consistent slug-type flow pattern during the steady state.