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Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Nonlinear Dispersive Model Equations, Jacob Grey Jan 2015

Analysis Of Nonlinear Dispersive Model Equations, Jacob Grey

LSU Doctoral Dissertations

In this work we begin with a brief survey of the classical fluid dynamics problem of water waves, and then proceed to derive well known evolution equations via a Hamiltonian Variational approach. This method was first introduced in the seminal work of Walter Craig, et al. \cite{CG}. The distinguishing feature of this scheme is that the Dirichlet-Neumann operator of the fluid domain appears explicitly in the Hamiltonian. In the second and third chapters, we utilize the Hamiltonian perturbation theory introduced in \cite{CG} to derive the Benjamin-Bona-Mahony (BBM) and Benjamin-Bona-Mahony-Kadomtsev-Petviashvili (BBM-KP)equations. Finally, we briefly review the existence theory for their corresponding …


Classification In The Presence Of Ordered Classes And Weighted Evaluative Attributes, Forrest Justin Osterman Jan 2015

Classification In The Presence Of Ordered Classes And Weighted Evaluative Attributes, Forrest Justin Osterman

LSU Doctoral Dissertations

We are interested in an important family of problems in the interface of the Multi-Attribute Decision-Making and Data Mining fields. This is a special case of the general classification problem, in which records describing entities of interest have been expressed in terms of a number of evaluative attributes. These attributes are associated with weights of importance, and both the data and the classes are ordinal. Our goal is to use historical records and the corresponding decisions to best estimate the class values of new data points in a way consistent with prior classification decisions, without knowledge of the weights of …


Fish Assemblage Structure, Distribution, And Trophic Ecology At Northwestern Gulf Of Mexico Banks, Todd Langland Jan 2015

Fish Assemblage Structure, Distribution, And Trophic Ecology At Northwestern Gulf Of Mexico Banks, Todd Langland

LSU Doctoral Dissertations

The northwest Gulf of Mexico (Gulf) shelf-edge banks both provide unique hard bottom habitat and support the northernmost coral reefs on the North American continental shelf in a region that is generally characterized by low relief, soft sediments. The habitat value of many of these banks has led to their designation as Habitat Areas of Particular Concern (HAPC) and the Flower Garden Banks National Marine Sanctuary (FGBNMS). However, little is known about the fisheries resources and dynamics of the banks outside the FGBNMS. This study had three main objectives: 1) define reef fish assemblages at northwestern Gulf shelf-edge banks and …


Holocene Palynology Of The Gulf Of Papua, Papua New Guinea: Using Modern Palynomorph Distribution To Better Constrain Paleoenvironmental Changes, Marie Louise Thomas Jan 2015

Holocene Palynology Of The Gulf Of Papua, Papua New Guinea: Using Modern Palynomorph Distribution To Better Constrain Paleoenvironmental Changes, Marie Louise Thomas

LSU Doctoral Dissertations

Multiple NSF (National Science Foundation)-funded MARGINS Source-to-Sink cruises were conducted in the Gulf of Papua (GoP), Papua New Guinea (PNG), from 2003 through 2005 to better understand how sediment is created, transported, and deposited. Although much work has been done on the data collected during these cruises, palynological analysis has never been conducted on the hundreds of available cores. The first phase of this project (Chapters 2 and 3) examines the connection between modern depositional regimes in the GoP and species assemblages recovered. Statistical analysis of palynomaceral assemblages (Chapter 2) indicates a correlation between their distribution and bathymetry, sedimentation rate, …


Effects Of Inbreeding On Endangered Red Wolves (Canis Rufus), Kristin E. Brzeski Jan 2015

Effects Of Inbreeding On Endangered Red Wolves (Canis Rufus), Kristin E. Brzeski

LSU Doctoral Dissertations

Inbreeding depression, the reduction in offspring fitness caused by mating among close relatives, is widespread in small populations and a major concern in conservation biology because it can affect population persistence. The negative effects of inbreeding results in the evolution of inbreeding avoidance behaviors; within small populations, such behaviors may encourage individuals to select mates outside of their respective species. Mate choice may also be facilitated by variation at major histocompatibility complex (MHC) genes, a gene group critical for immune response and disease resistance. Given broad impacts of inbreeding and MHC variation on fitness and behavior, evaluating their effects is …


Developing Recognition Criteria For Current-Wave-Enhanced Sediment Gravity Flows, Kathryn Christine Denommee Jan 2015

Developing Recognition Criteria For Current-Wave-Enhanced Sediment Gravity Flows, Kathryn Christine Denommee

LSU Doctoral Dissertations

Sedimentary fabrics preserved in the rock record provide some of the best evidence for interpreting paleo-depositional conditions. Muddy sediments in particular are important paleoenvironmental archives, preserving the most complete stratigraphic record of any rock type in basinal settings. However, the full range of mechanisms responsible for the deposition of muddy sediments, particularly in high-energy settings, remains poorly understood. Although frequently observed in modern settings, muddy prodeltaic deposits are rarely identified in the rock record, in part because no catalogue of easily distinguishable recognition criteria exists for this class of mudstones. In order to help overcome this deficiency, this dissertation project …


Computational Studies On Bimetallic Catalysis And X-Ray Absorption Spectroscopy, Sayakkarage R. G. Fernando Jan 2015

Computational Studies On Bimetallic Catalysis And X-Ray Absorption Spectroscopy, Sayakkarage R. G. Fernando

LSU Doctoral Dissertations

Computational studies are very important to gain an insight into reaction mechanisms and in interpreting and understanding complicated experimental observations. This report contains a discussion on computational studies performed on bimetallic catalysis and on X-ray absorption spectroscopy of insulators. The viability of a bimetallic rhodium and cobalt catalysts for industrially important hydroformylation and aldehyde-water shift catalysis (AWS) is discussed. Density functional theory (DFT) studies were used for bimetallic catalysis and time-dependent DFT studies were used for excited state dynamics. These studies were performed using Gaussian 09 package and NWChem. Hydroformylation is experimentally performed in acetone and 30% water/acetone systems and …


Development Of Transition Metal-Catalyzed Polymerization Reactions And Their Applications For The Preparation Of Well-Defined Conjugated Polymer Architectures, Carlos Anthony Chavez Jan 2015

Development Of Transition Metal-Catalyzed Polymerization Reactions And Their Applications For The Preparation Of Well-Defined Conjugated Polymer Architectures, Carlos Anthony Chavez

LSU Doctoral Dissertations

The synthesis of conjugated polymers and design of complex materials based on them have become increasingly popular as the demand for low-cost efficient and processible optoelectronic and semiconducting devices escalates. While advanced applications of polymeric materials require some degree of sophistication, success can be achieved through careful consideration of polymerization techniques and methodologies. Controlling critical aspects of the polymerization process allows for synthesis of complex macromolecular architectures possessing unique and novel properties that may be worth of further comprehensive investigation. This dissertation primarily focuses on the development and preparation of well-defined hierarchical macromolecular architectures. The foundation of this work encompasses …


Three Year Assessment Of Nearshore Crude Oil Contamination In The Gulf Of Mexico Using Gulf Menhaden (Brevoortia Patronus) As An Indicator Species: Menhaden Watch, Gregory Michael Olson Jan 2015

Three Year Assessment Of Nearshore Crude Oil Contamination In The Gulf Of Mexico Using Gulf Menhaden (Brevoortia Patronus) As An Indicator Species: Menhaden Watch, Gregory Michael Olson

LSU Doctoral Dissertations

Approximately 4.9 million barrels of crude oil along with natural gas were released into the Gulf of Mexico (GoM) from April to July 2010 (Deepwater Horizon, DWH, spill). Impacts of this magnitude seldom occur in the GoM (Ixtoc I was the last spill close to this magnitude occurring in 1979), and one cannot predict when they will happen. Major constituents of concern found in crude oil are Polycyclic Aromatic Hydrocarbons (PAHs), which often have low volatility that allows for prolonged existence in the environment. PAHs are compounds of concern according to the United States Environmental Protection Agency (USEPA), with one …


Investigating The Photorecombination Dynamics In Molecular High-Harmonic Spectra, Benjamin Parker Wilson Jan 2015

Investigating The Photorecombination Dynamics In Molecular High-Harmonic Spectra, Benjamin Parker Wilson

LSU Doctoral Dissertations

The work presented in this dissertation will relate the photorecombination dynamics to photoionization dynamics in SF6 utilizing the self-probing mechanism, high harmonic generation (HHG). This work specifically aims to establish parameters for which the comparison is applicable and the macroscopic complications inherent in HHG do not interfere with the extraction of dynamic information. The first part of this work established the macroscopic experimental apparatus necessary for consistent spectroscopic observation. It is shown that using a gas jet that is an order of magnitude shorter than the Rayleigh length of the driving laser results in more consistent harmonic spatial profiles and …


A New Method In Distribution Theory With A Non-Smooth Framework, Yunyun Yang Jan 2015

A New Method In Distribution Theory With A Non-Smooth Framework, Yunyun Yang

LSU Doctoral Dissertations

In this work, we present a complete treatment of the theory of thick distributions and its asymptotic expansion. We also present several applications of thick distributions in mathematical physics, function spaces, and measure theory. We also discuss regularization using different surfaces. In the last chapter we present some recent applications of distributions in clarifying the moment terms in the heat kernel expansion, and in explaining the relation between the heat kernel expansion and the cylinder kernel expansion.


Holecene Paleoenvironmental Reconstruction From The Shark River Estuary, Everglades, Florida, Qiang Yao Jan 2015

Holecene Paleoenvironmental Reconstruction From The Shark River Estuary, Everglades, Florida, Qiang Yao

LSU Doctoral Dissertations

This dissertation examines the paleoecological records from the Shark River Estuary in the southwestern part of the Everglades National Park (ENP), Florida, with primary goal of reconstructing the Holocene history of the coastal mangrove ecosystem in the Florida Coastal Everglades. Roughly 15 meters of sediments were collected from 4 study sites and subjected to loss-on ignition, palynological, and X-ray fluorescence analyses. According to the literature, the earliest communities of Rhizophora mangle (red mangrove) occurred prior to 8,000 cal yr BP in the south-central area of the Belize Barrier Reef Platform. Between 7,000 and 5,000 cal yr BP, Rhizophora was established …


Polycyclic Aromatic Hydrocarbons Dynamics In The Northern Gulf Of Mexico, Puspa Lal Adhikari Jan 2015

Polycyclic Aromatic Hydrocarbons Dynamics In The Northern Gulf Of Mexico, Puspa Lal Adhikari

LSU Doctoral Dissertations

Polycyclic aromatic hydrocarbons (PAHs) are introduced into the marine environment via oil seeps/spills, riverine discharges, continental runoff, coastal erosion, and atmospheric deposition. An estimated 2.1 x 1010g of PAHs entered into the northern Gulf of Mexico (GOM) during the Deepwater Horizon (DWH) oil spill in 2010. It became evident following the oil spill that accurate quantification of ultimate fate of these potentially carcinogenic and/or mutagenic organic pollutants is extremely challenging. In general, very little is known about PAHs fate, distribution and accumulation in the open ocean ecosystems. This study determines the upper ocean vertical fluxes and sedimentary PAHs accumulation rates …


Game Theoretic Analyses Of The United States-Canada Softwood Lumber Trade, Rajan Parajuli Jan 2015

Game Theoretic Analyses Of The United States-Canada Softwood Lumber Trade, Rajan Parajuli

LSU Doctoral Dissertations

The ongoing softwood lumber trade dispute between the United States (U.S.) and Canada is one of the most contentious and largest bilateral trade battles over the recent decades. The bilateral trade debate is mostly because of the different forestland ownership systems in the U.S. and Canada, and the alleged timber subsidies by provincial governments to Canadian lumber producers. The Softwood Lumber Agreement (SLA) 2006 between the U.S. and Canada is the latest transitory solution of this dispute, entailing Canada to impose mandatory export charges on its lumber shipments to the U.S. In order to understand this trade dispute from a …


Exploring Superconductivity In Chiral Structured Aube, Drew Jared Rebar Jan 2015

Exploring Superconductivity In Chiral Structured Aube, Drew Jared Rebar

LSU Doctoral Dissertations

AuBe is a noncentrosymmetric superconductor with the B20 FeSi-type structure. Noncentrosymmetric superconductors are expected to give rise to unconventional superconductivity due to spin orbit coupling and a mixed spin-singlet, spin-triplet state. The B20 structure of AuBe is particularly interesting since this is one of the only known crystal structures for bulk magnetic skyrmions in materials such as MnSi and Cu2OSeO3. The superconducting state was characterized by specific heat, dc magnetization, ac susceptibility, and resistivity. Specific heat revealed AuBe to host an isotropic gap characteristic of predominantly s-wave spin-singlet pairing in the weak coupling limit. Magnetization and susceptibility measurements revealed a …


A Spatial Dynamic Model Of Population Changes In A Vulnerable Coastal Environment, Kenan Li Jan 2015

A Spatial Dynamic Model Of Population Changes In A Vulnerable Coastal Environment, Kenan Li

LSU Doctoral Dissertations

Achieving coastal sustainability in low-lying coastal areas is a great challenge. This study developed a spatial dynamic model to study the coupled natural-human responses in the form of population changes in the Lower Mississippi River Basin region. The goal was to identify the key social-economic factors (utility) and selected environmental factors (such as hazards damage, elevation, and subsidence rate) that affect population changes, as well as how population changes affect the local utility and the local environment reciprocally. The study area was partitioned into the “north’ and the “south” by a hypothetical boundary to test the differences of the emergence. …


Large-Scale Geometric Data Decomposition, Processing And Structured Mesh Generation, Wuyi Yu Jan 2015

Large-Scale Geometric Data Decomposition, Processing And Structured Mesh Generation, Wuyi Yu

LSU Doctoral Dissertations

Mesh generation is a fundamental and critical problem in geometric data modeling and processing. In most scientific and engineering tasks that involve numerical computations and simulations on 2D/3D regions or on curved geometric objects, discretizing or approximating the geometric data using a polygonal or polyhedral meshes is always the first step of the procedure. The quality of this tessellation often dictates the subsequent computation accuracy, efficiency, and numerical stability. When compared with unstructured meshes, the structured meshes are favored in many scientific/engineering tasks due to their good properties. However, generating high-quality structured mesh remains challenging, especially for complex or large-scale …


String Searching With Ranking Constraints And Uncertainty, Sudip Biswas Jan 2015

String Searching With Ranking Constraints And Uncertainty, Sudip Biswas

LSU Doctoral Dissertations

Strings play an important role in many areas of computer science. Searching pattern in a string or string collection is one of the most classic problems. Different variations of this problem such as document retrieval, ranked document retrieval, dictionary matching has been well studied. Enormous growth of internet, large genomic projects, sensor networks, digital libraries necessitates not just efficient algorithms and data structures for the general string indexing, but indexes for texts with fuzzy information and support for queries with different constraints. This dissertation addresses some of these problems and proposes indexing solutions. One such variation is document retrieval query …


Magnetic Susceptibility Of North American Ordovician Epicontinental Seas: Spatial Variability And Sandbian-Katian Boundary Correlation, Thomas J. Schramm Jan 2015

Magnetic Susceptibility Of North American Ordovician Epicontinental Seas: Spatial Variability And Sandbian-Katian Boundary Correlation, Thomas J. Schramm

LSU Doctoral Dissertations

Magnetic susceptibility (χ) has gained increased usage as a stratigraphic correlation tool. This project evaluates the utility of a χ correlation tool, including its shortcomings, and attempts its integration with other datasets. The Upper Ordovician of eastern North America represent the stratigraphic interval in which these experiments were conducted. 4566 samples were collected for the purposes of this study, and χ was measured on 3345 of the samples. This project includes three major facets, 1) the spatial variability of χ, 2) correlation of Sandbian-Katian boundary interval strata in eastern North America using χ, and 3) utility of χ for interpreting …


Using Trace Fossils To Determine The Role Of Oceanic Anoxic Event Ii On The Cretaceous Western Interior Seaway Paleoenvironment, Jacob Frederick Grosskopf Jan 2015

Using Trace Fossils To Determine The Role Of Oceanic Anoxic Event Ii On The Cretaceous Western Interior Seaway Paleoenvironment, Jacob Frederick Grosskopf

LSU Doctoral Dissertations

Did well-oxygenated benthic conditions exist in all parts of the Cretaceous Western Interior Seaway (CWIS) during the deposition of Bed 63 at the onset Oceanic Anoxic Event II (OAE II), as suggested by findings from two cores from the central portion of the CWIS? This problem was approached by categorizing the bioturbation that is prevalent through Bed 63 into oxygen-related ichnofabrics (ORI) in order to describe benthic oxygen conditions. These data were collected from outcrop and core among seven different sites along West–East and North–South transects that traversed portions of the CWIS with differing depositional settings and proximities to the …


Numerical Simulation Of Cold Front-Related Hydrodynamics Of Wax Lake Delta, Qian Zhang Jan 2015

Numerical Simulation Of Cold Front-Related Hydrodynamics Of Wax Lake Delta, Qian Zhang

LSU Doctoral Dissertations

This study applies a three-dimensional numerical model ECOM-si to simulate the circulation in the Wax Lake delta under winter cold front conditions. This model uses real topography and bathymetry of the area to reproduce tides and the circulation between December 2012 and January 2013, which captures a total of seven cold front passages. The model results demonstrate that the circulation in the Wax Lake delta area is significantly affected by the winter cold fronts. The major findings are: (1) Water fluxes in the delta distributary network are not solely propagated within the channels but also between the channels, indicating inundation …


Photoelectrons And Recombining Electrons In Atomic And Molecular Systems, Kristen D'Ann Fulfer Jan 2015

Photoelectrons And Recombining Electrons In Atomic And Molecular Systems, Kristen D'Ann Fulfer

LSU Doctoral Dissertations

This work in this dissertation explores how photoelectrons enter and exit atoms and molecules. The electron rescattering events which may occur during photoionization or photorecombination processes play a dominant role in the understanding of how photoelectrons enter and exit molecules, which is intrinsically linked to how chemical reactions occur. Chapters 3-4 of this dissertation present evidence of vibrational mode specific breakdown of the Franck-Condon Principle in the photoionization of low symmetry molecules, acrolein and the singly halogenated thiophenes, due to resonant and non-resonant electron rescattering dynamics. In Chapters 5-6, the disentanglement of the valence electronic structure, as well as evidence …


Platinum Complexes With Tridentate Ligands As Models For Active Monofunctional Anticancer Drugs, Chase Koby Andrepont Jan 2015

Platinum Complexes With Tridentate Ligands As Models For Active Monofunctional Anticancer Drugs, Chase Koby Andrepont

LSU Doctoral Dissertations

Pt(II) complexes bind preferentially at N7 of G residues of DNA, causing DNA structural distortions associated with anticancer activity. Some distortions induced by difunctional cisplatin are also found for monofunctional Pt(II) complexes with carrier ligands having bulk projecting toward the guanine base. This ligand bulk can be correlated with impeded rotation about the Pt–N7(guanine) bond. The objective of this study is to understand the influences of in-plane bulk of Pt(Ltri)G adducts (Ltri = tridentate carrier ligand, G = guanine derivative bound to a metal, but not tethered to another nucleobase). NMR spectroscopy provided conclusive evidence that Pt(Ltri)G (Ltri = di-(2-picolyl)amine …


Seismic Velocity Characteristics Of Partially Saturated Unconsolidated Sediments, Jie Shen Jan 2015

Seismic Velocity Characteristics Of Partially Saturated Unconsolidated Sediments, Jie Shen

LSU Doctoral Dissertations

Seismic velocity models of the near-surface (< 30 m) better explain seismic velocities when all elements of total effective stress are considered, particularly in materials with large cohesive and soil suction stress such as clays. Traditional constitutive elastic models assume interparticle and soil suction stresses are negligible. This study proposes a new methodology which corrects total effective stress in Hertz-Mindlin theory for interparticle and soil suction and calculates the elastic moduli by extending Biot-Gassmann theory to include pressure effects induced by water saturation changes and cohesion. The proposed model predicts seismic velocities that correlate well with measured field velocities from the literature. Soil density, porosity, elastic moduli and the soil-water characteristic curve (SWCC) are important properties for soil characterization. Currently, geotechnical and laboratory tests for soil properties are costly and limited to point sampling sites. Seismic surveys can potentially provide laterally continuous soil property values that may complement geotechnical borehole tests with low cost. We propose a new method to invert for soil properties and the SWCC from seismic P- and S-wave velocity-vs.-depth profiles interpreted from shallow (< 25 m depth) unconsolidated sediments under conditions of near-full saturation (> 99%). The results from seismic soil property inversion are validated by comparison to geotechnical and laboratory results conducted independently in the same area as the seismic survey. Knowledge of homogeneous and heterogeneous fluid-distribution patterns is important for the estimation of oil reserves, reservoir simulation, the interpretation of time-lapse seismic, and the selection of remediation techniques for groundwater contamination. Problems exist in determining in-situ fluid-distribution patterns in unconsolidated sediments because laboratory tests on core samples may not be representative of in-situ conditions. We propose a new method to determine in-situ fluid-distribution patterns by inverting …


A Trust-Based Relay Selection Approach To The Multi-Hop Network Formation Problem In Cognitive Radio Networks, Brandy Michelle Tyson Jan 2015

A Trust-Based Relay Selection Approach To The Multi-Hop Network Formation Problem In Cognitive Radio Networks, Brandy Michelle Tyson

LSU Doctoral Dissertations

One of the major challenges for today’s wireless communications is to meet the growing demand for supporting an increasing diversity of wireless applications with limited spectrum resource. In cooperative communications and networking, users share resources and collaborate in a distributed approach, similar to entities of active social groups in self organizational communities. Users’ information may be shared by the user and also by the cooperative users, in distributed transmission. Cooperative communications and networking is a fairly new communication paradigm that promises significant capacity and multiplexing gain increase in wireless networks. This research will provide a cooperative relay selection framework that …


Chemically Patterned Surfaces As Test Platforms To Study Magnetic And Solvent-Responsive Properties At The Nanoscale: Investigations Using Scanning Probe Microscopy, Shalaka Kulkarni Jan 2015

Chemically Patterned Surfaces As Test Platforms To Study Magnetic And Solvent-Responsive Properties At The Nanoscale: Investigations Using Scanning Probe Microscopy, Shalaka Kulkarni

LSU Doctoral Dissertations

Chemically patterned surfaces were fabricated using a combination of molecular self-assembly and particle lithography to generate billions of nanostructures of organosilane self-assembled monolayers (SAMs). Monodisperse mesospheres were used as surface masks to prepare nanostructures on flat surfaces using the simple benchtop chemistry steps of mixing, centrifuging, evaporation, and drying. Periodic arrays of well-defined organosilane nanostructures serve as discrete surface sites for the selective deposition of polymers and magnetic nanoparticles.

In this dissertation, particle lithography approaches for surface patterning provide new directions for studying surface chemistry at the molecular-level using high resolution investigations with scanning probe microscopy (SPM). Atomic force microscopy …


Seavipers - Computer Vision And Inertial Position Reference Sensor System (Cviprss), Justin Lee Erdman Jan 2015

Seavipers - Computer Vision And Inertial Position Reference Sensor System (Cviprss), Justin Lee Erdman

LSU Doctoral Dissertations

This work describes the design and development of an optical, Computer Vision (CV) based sensor for use as a Position Reference System (PRS) in Dynamic Positioning (DP). Using a combination of robotics and CV techniques, the sensor provides range and heading information to a selected reference object. The proposed optical system is superior to existing ones because it does not depend upon special reflectors nor does it require a lengthy set-up time. This system, the Computer Vision and Inertial Position Reference Sensor System (CVIPRSS, pronounced \nickname), combines a laser rangefinder, infrared camera, and a pan--tilt unit with the robust TLD …


First-Principles And Many-Body Methods: Implementations And Applications To Study Spintronic Materials, Ryky Nelson Jan 2015

First-Principles And Many-Body Methods: Implementations And Applications To Study Spintronic Materials, Ryky Nelson

LSU Doctoral Dissertations

Diluted magnetic semiconductors (DMSs) and magnetoresistive materials are instrumental for the development of spintronic technology. Before we are able to engineer spintronic devices, it is necessary to understand the properties of materials from which spintronic devices are made, otherwise time and other resources will be wasted. In this thesis, we investigate some aspects of diluted magnetic semiconductors and a magnetoresistive material Ta2PdSe6 with first-principle and many-body methods. Particularly, we investigate the Mn valence in (Ga,Mn)N and derive low-energy models of (Ga,Mn)N by making use of a first-principles Wannier-function analysis. Additionally, we also study the disorder-driven localization in DMSs with the …


A Monte Carlo Approach To Studying The Hydrogen Storage Capabilities Of Potassium Magnesium Hydride (Kmgh3), Brandon L. Borill Jan 2015

A Monte Carlo Approach To Studying The Hydrogen Storage Capabilities Of Potassium Magnesium Hydride (Kmgh3), Brandon L. Borill

LSU Doctoral Dissertations

Grand Canonical Monte Carlo (GCMC) simulations and the weighted histogram analysis method (WHAM) were employed at selected temperatures and pressures in the study of the hydrogen storage capabilities of KMgH3. A specially tailored addition/removal algorithm was employed to add hydrogen directly at the lattice sites. Agreement between experimental results was obtained through GCMC simulations. WHAM type studies were employed to obtain probability distributions for the purpose of learning the probability of finding hydrogen atoms at specific temperatures and hydrogen pressures. The radial distribution function was employed to study the changes in the structure of KMgH3 for the selected model as …


Design And Application Of Task-Specific Organic Salts For Chemical And Biochemical Sensing, Waduge Indika Subodha Galpothdeniya Jan 2015

Design And Application Of Task-Specific Organic Salts For Chemical And Biochemical Sensing, Waduge Indika Subodha Galpothdeniya

LSU Doctoral Dissertations

There is an increasing demand for development of new sensors and sensor strategies for accurate detection and discrimination of various analytes. In this regard, colorimetric and fluorometric sensor approaches have attracted considerable attention, primarily because they represent facile and inexpensive analytical tools. In this dissertation, I discuss the design and application of sensors and sensor arrays using task specific organic salts: ionic liquids (ILs) and a group of uniform materials based on organic salts (GUMBOS). As compared to typical ionic compounds, these two classes of organic salts exhibit relatively lower melting points due to bulky organic cations and/or anions. Interestingly, …