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Reissued 30 May 2017 with Second Reader’s non-NPS affiliation added to title page. / Approved for public release; distribution is unlimited / The purpose of this thesis is to characterize typical levels of vibrational noise on the ocean floor to ascertain the vibration's effect on possible future bottom mounted sensors. The data used for this thesis was obtained from publicly available recorded information from four ocean bottom seismometers (OBS). The OBSs were located in two geographical choke points: the Luzon Strait and west of the Strait of Juan de Fuca. These highly trafficked choke points were considered to be a good representation of where these experimental bottom mounted sensors might be located should they be built. Unix-based seismic processing software available from the Incorporated Research Institutions for Seismology (IRIS) proved essential to obtaining calibrated data, and the methodology used to get the calibrated data is discussed in detail. The results showed that one OBS out of the four was highly variable, with decibel levels varying widely from day to day. The other OBSs remained fairly consistent. In addition, there were no common discrete frequencies between sensors that were in the same geographic area. Recommended future research involves the study of environmental effects on the OBSs, additional research to correlate the results observed in the Luzon Strait, and a look into the electronic noise floors of the OBSs used. / Lieutenant Commander, United States Navy

The method of isotope substitution in neutron spectroscopy is introduced to measure for the rst time the partial vibrational density of states of two network glass forming systems, namely GeSe2 at temperatures of 5, 20 and 292 K and GeO2 at a temperature of 10 K. This work included the development of a new data analysis procedure involving corrections for e.g. beam attenuation, multiple scattering and multiple phonon scattering. The measurements were made using the MARI and MERLIN spectrometers at the ISIS pulsed neutron source where measurements of the elastic lines were used to help deduce the mean squared atomic displacements and Debye-Waller factors. In the case of GeSe2, the latter were found as a function of temperature between 10 and 280 K. The results for GeSe2 glass at temperatures of 5, 20, and 292 K were found to be in good agreement, proving the ecacy of the data correction procedure. For both GeSe2 and GeO2, the results were interpreted with the aid of molecular dynamics simulations to identify the energies corresponding to rocking, bending and stretching motions. The method of in situ high pressure neutron diraction was developed using double toroid sintered diamond anvils in a Paris-Edinburgh press to measure, for the rst time, reliable diraction patterns for GeO2, SiO2 and B2O3 glasses at pressures up to 17.5 GPa. The total pair distribution functions were obtained, allowing the nearest neighbour Ge-O, Si-O or B-O coordination numbers and bond distances to be calculated. The glass networks collapse by two principal mechanisms. The rst mechanism, at lower pressures, involves a rearrangement of the structural motifs on an intermediate range length scale. The second mechanism, above thresholds in pressure of 5, 20 and 9 GPa for GeO2, SiO2 and B2O3, respectively, involves a change in the nature of the structural motifs.

Vibrational and thermal behavior of several important systems were studied. The first study was a measurement of the infrared vibrational spectra of glucose and two important glucose dimers (cellobiose and maltose) as a function of temperature. The purpose of his study was to measure shifts in vibrational band positions to gain insight into carbohydrate reactivity. The second study was on hydrothermally treated coffee waste biomass. Here, collaborators at University of Campinas (UNICAMP, Brazil) treated coffee waste biomass in a flow-through subcritical water hydrolysis reactor. The purpose of the M.S. study on coffee waste was to understand the chemical changes that occurred to the residual solids during hydrolysis treatment. Vibrational spectroscopy and thermal analysis techniques were used. The third and final study was to understand the chemical composition of the solid product resulting from co-solvent enhanced lignin fractionation (CELF) of several biomass feeds. Collaborators at University of California Riverside (UCR) recently developed the CELF process. The purpose of the M.S. study on the CELF solid product was to understand its composition to help guide the CELF reactor design and determine applications for the CELF solids. Taken together, the 3 studies are integrated into a cohesive whole that demonstrates the use of spectroscopic and thermal techniques for characterizing biomass and understanding its composition at the molecular level.

The Skyrme model enables us to approximate nuclei via topological solitons known as Skyrmions. The B = 4 Skyrmion is of particular importance as its symmetry and stability means that multiple B = 4 Skyrmions can combine with each other to form larger B = 4N Skyrmions. In this thesis we investigate the properties of these B = 4N Skyrmions and compare them with results found in the wider nuclear physics community. We go beyond rigid body quantization and develop a formalism of using vibrational quantisation to generate the energy spectrum of the Oxygen−16 nucleus. The Oxygen−16 nucleus is treated as an arrangement of four B = 4 Skyrmions, whose dynamics enable us to create a 2−dimensional manifold of B = 16 configurations. We solve the Schrödinger equation on this manifold and discover new states previously not found in the B = 16 sector of the Skyrme model. We compare these states with those found experimentally and find that there is a excellent it to the energy spectrum. In order to apply vibrational quantization to a wider range of nuclei we create a novel approximation for Skyrmions and the interactions between them. By generating Skyrmions with Gaussian sources we find analytic expressions for the pion fields and interaction energies of Skyrmions, with particular focus on the B = 1 and B = 4 Skyrmions, and show how this could be applied to vibrational quantization and the clustering of B = 4 Skyrmions. B = 4N nuclei are the only nuclei with zero spin and isospin, which means that their electric charge density is proportional to their baryon density. This simplification makes these nuclei particularly susceptible to investigation via electron scattering. We develop a classical averaging method to calculate the Patterson function and the form factor for a B = 4N nucleus and make comparisons with experimental data. We also discover a way of using the baryon density directly to approximate the locations of zeroes and stationary points of the form factor.

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The present work examines line measurements of pressure, temperature, and density in high speed, non-isobaric flows emanating from an underexpanded jet nozzle. Line images of rotational and vibrational Raman spectra are collected for a 8-mm linear laser probe, and are combined onto the same EMCCD detector. Combining the two techniques allows for a single-shot measurement of major species, pressure, and temperature in a turbulent non-isobaric environment that is chemically reacting. Temperature measurements along the laser test section are extracted from the rotational Raman spectrum, whereas major species densities are measured by examining the intensities of their respective vibrational Raman lines. Pressure can be calculated using an equation of state, in every location along the linear laser probe. The technique feasibility is examined by performing measurements of pressure, temperature and density in a non-reacting underexpanded air jet where the chemical composition is constant and known. Future work will extend the technique to chemically reacting supersonic flows with unknown chemical composition.

Coherent anti-Stokes Raman scattering (CARS) microscopy allows fast, label-free and chemically selective imaging of condensed-phase samples thanks to its high signal sensitivity. It also offers several other advantages such as intrinsic three-dimensional sectioning capability, longer penetration depth and high spatial resolution. In conventional CARS microscopy, two synchronized narrowband laser pulses are typically used to generate signals at a single vibrational resonance, from which vibrational images are constructed. Although this type of CARS methods has been proven to be an excellent visualizing tool for lipid in biological samples, it has two serious problems. First, the ubiquitous nonresonant background smears out vibrational signals, which makes quantitative image analysis very difficult. Second, the chemical information obtained in this method is seriously limited since only a single vibrational resonance is measured, which is far less information than full vibrational spectrum can offer. In the past few years, we have developed several novel CARS imaging techniques that can overcome these issues. All our methods require only a single broadband laser and produce background-free vibrational spectrum by combining the laser pulse shaping and various signal detection schemes. The first one obtains a vibrational spectrum over 800 ~ 1800 cm-1 in a single measurement by simultaneous excitation of multiple vibrational resonances and analysis of spectral interferences between the resonant and nonresonant signals. The second method adopts the spectral focusing mechanism, where stretched broadband pulses are used to excite a single vibrational resonance with great sensitivity. A novel frequency modulation (FM) scheme is invented to eliminate the non-resonant background. Complimentary spectral analysis algorithm is also developed to obtain quantitative CARS signals at the CH stretching region (2800 ~ 3100 cm-1). In this dissertation, the fundamental mechanisms, experimental implementations and various imaging applications of the above CARS methods are described in detail. / text

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