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Full-Text Articles in Physical Sciences and Mathematics

Evolution Of Structural And Physical Properties Of Transition Metal Oxide Sr₃(Ru₁₋Xmnx)₂O₇ (0 <̲ X >̲ 0.7) With Mn Concentration, Biao Hu Jan 2011

Evolution Of Structural And Physical Properties Of Transition Metal Oxide Sr₃(Ru₁₋Xmnx)₂O₇ (0 <̲ X >̲ 0.7) With Mn Concentration, Biao Hu

LSU Doctoral Dissertations

Correlated Electron Materials (CEMs) have attracted the attention of the materials community because the strong coupling between charge, lattice, orbital, and spin degrees of freedom produces exotic phenomena. Transition metal oxide series Srn+1RunO3n+1 (n = 1 to ∞) is a prototype of CEMs. The n = 2 member of this family Sr3Ru2O7 is the subject of this dissertation. It has a paramagnetic (PM) metallic ground state, which can be driven into an antiferromagnetic (AFM) insulator with a partial substitution of Ru by Mn. The focus of this research is to understand the role of chemical doping as the driving force …


Next Generation Multi-Scale Quantum Simulations For Strongly Correlated Materials, Shuxiang Yang Jan 2011

Next Generation Multi-Scale Quantum Simulations For Strongly Correlated Materials, Shuxiang Yang

LSU Doctoral Dissertations

This thesis represents our effort to develop the next generation multi-scale quantum simulation methods suitable for strongly-correlated materials, where complicated phase-diagrams prevail, suggesting complicated underlying physics. We first give a detailed description of the parquet formalism. With its help, different approximate methods can be unified and a hierarchy of approximate methods with different accuracies and computational complexity can thus be designed. Next, we present a numerical solution of the parquet approximation. Results on the Hubbard model are compared to those obtained from Determinant Quantum Monte Carlo (DQMC), FLuctuation EXchange (FLEX), and self-consistent second-order approximation methods. The comparison shows a satisfactory …


A Multifaceted Phenomenon Of Hydrophobic Effects: Insights Learned From Nucleation Algorithm Based Computer Simulation Approach, Hyunmi Kim Jan 2011

A Multifaceted Phenomenon Of Hydrophobic Effects: Insights Learned From Nucleation Algorithm Based Computer Simulation Approach, Hyunmi Kim

LSU Doctoral Dissertations

We have applied our new approach, a combination of the AVUS-HR nucleation algorithm and a thermodynamic cycle, to the studies of hydrophobicity-related researches. Due to the multifaceted characteristics of hydrophobicity, it is essential to acquire knowledge in various environments where hydrophobic relevant events occur for comprehensive understanding of this process. In this regards, we have chosen two relatively unstudied hydrophobic subjects for application of our new methodology. For the first subject, hydrophobic association behaviors of a methane pair confined into a nanometer sized hydrophobic cavity have been investigated. Our new approach demonstrates that the association behavior between two methane molecules …


Testing And Improving The Luminosity Relations For Gamma-Ray Bursts, Andrew Collazzi Jan 2011

Testing And Improving The Luminosity Relations For Gamma-Ray Bursts, Andrew Collazzi

LSU Doctoral Dissertations

Gamma Ray Bursts (GRBs) have several luminosity relations where a measurable property of a burst light curve or spectrum is correlated with the burst luminosity. These luminosity relations are calibrated for the fraction of bursts with spectroscopic redshifts and hence the known luminosities. GRBs have thus become known as a type of "standard candle"; where standard candle is meant in the usual sense that their luminosities can be derived from measurable properties of the bursts. GRBs can therefore be used for the same cosmology applications as Type Ia supernovae, including the construction of the Hubble Diagram and measuring massive star …


Formation And Stabilization Of Combustion-Generated Environmentally Persistent Free Radicals On Transition Metal Oxides Supported On Silica, Eric Warren Pimentel Vejerano Jan 2011

Formation And Stabilization Of Combustion-Generated Environmentally Persistent Free Radicals On Transition Metal Oxides Supported On Silica, Eric Warren Pimentel Vejerano

LSU Doctoral Dissertations

The formation of environmentally persistent free radicals in combustion system was investigated from chemisorptions of chlorine- and hydroxy-substituted benzenes on transition metal oxide surface under post-combustion conditions. This manuscript reports the formation of EPFRs on silica particles containing 5% Fe(III)2O3, Ni(II)O, and Zn(II)O. The EPFRs are formed by the chemisorption of substituted aromatic molecular adsorbates on the metal cation center followed by electron transfer from the adsorbate to the metal ion at temperatures from 150 to 400 oC. Depending on the nature of the adsorbate and the temperature, two organic EPFRs were formed: a phenoxyl-type radical, which has a lower …


Redox-Active Liposome Delivery Agents With Highly Controllable Stimuli-Responsive Behavior, Nicole Hollabaugh Carrier Jan 2011

Redox-Active Liposome Delivery Agents With Highly Controllable Stimuli-Responsive Behavior, Nicole Hollabaugh Carrier

LSU Doctoral Dissertations

Over the last few decades, liposomes have generated a lot of interest as drug delivery vehicles to address the need for providing both increased therapeutic efficacy and decreased systemic exposure, simultaneously. The challenge of increasing drug accumulation at diseased sites, without compromising the integrity and stability of the liposomal carrier during circulation, has been met with two possible solutions: (1) active targeting and (2) active triggering. To achieve selective and site-specific delivery of drugs to tumors, active triggering methods have been developed wherein a responsive element is incorporated into the liposomal bilayer, which causes destabilization of the liposome upon exposure …


Guided Modes And Resonant Transmission In Periodic Structures, Hairui Tu Jan 2011

Guided Modes And Resonant Transmission In Periodic Structures, Hairui Tu

LSU Doctoral Dissertations

We analyze resonant scattering phenomena of scalar fields in periodic slab and pillar structures that are related to the interaction between guided modes of the structure and plane waves emanating from the exterior. The mechanism for the resonance is the nonrobust nature of the guided modes with respect to perturbations of the wavenumber, which reflects the fact that the frequency of the mode is embedded in the continuous spectrum of the pseudo-periodic Helmholtz equation. We extend previous complex perturbation analysis of transmission anomalies to structures whose coefficients are only required to be measurable and bounded from above and below, and …


Structure-Function Relationships In Poly(3-Hexylthiophene)S Formed Via Manipulation Of Oxidative Coupling Routes, Warren James Solfiell Jan 2011

Structure-Function Relationships In Poly(3-Hexylthiophene)S Formed Via Manipulation Of Oxidative Coupling Routes, Warren James Solfiell

LSU Doctoral Dissertations

This investigation focused on the analytical characterization of poly(3-hexylthiophene), a heterocyclic conducting polymer system, with an overall objective of elucidating the effects that the experimental conditions during chemical oxidation using iron(III) chloride as an oxidant impart on the structure of the resulting polymers. Poly(3-alkylthiophene)s are extensively studied materials due to their high electrical conductivities and unique optical properties that make them extremely valuable for use in contemporary technological applications and devices. Specifically, the aim of this research was to determine the dependence of structural characteristics, such as endgroups, molecular weights, and regioregularities, on the solvent employed for the reaction and …


Cognitive Radio Network With A Distributed Control Channel And Quality-Of-Service Solution, Urban Terrell Wiggins Jan 2011

Cognitive Radio Network With A Distributed Control Channel And Quality-Of-Service Solution, Urban Terrell Wiggins

LSU Doctoral Dissertations

The proliferation of wireless access and applications to the Internet and the advent of a myriad of highly evolved portable communication devices; creates the need for an efficiently utilized radio spectrum. This is paramount in the licensed and unlicensed radio frequency bands, that spawn an exponential growth in Dynamic Spectrum Access (DSA) research, Cognitive Radio (CR) and Cognitive Radio Networks (CRN) research. DSA research has given way to the paradigm shift toward CR with its dynamic changes in transmission schemas. This paradigm shift from a fixed and centralized frequency spectrum environment has morphed into a dynamic and decentralized one. CR …


Fabrication Of Organosilane Nanostructures As Selective Sites For Surface Chemical Reactions, Kathie Lee Lusker Jan 2011

Fabrication Of Organosilane Nanostructures As Selective Sites For Surface Chemical Reactions, Kathie Lee Lusker

LSU Doctoral Dissertations

Naturally self-assembled mesospheres provide a practical route for controlling the arrangement of materials on surfaces at the nanoscale. Periodic arrays of well-defined nanostructures can be produced with different nanomaterials and interpattern spacings. Results presented in this dissertation demonstrate particle lithography methods developed for fabricating arrays of organosilane nanostructures. Surfaces were designed for the selective deposition of polymers and nanoparticles to produce multicomponent nanopatterns. The approaches for surface patterning provide new directions for studying surface chemistry at the molecular-level, and have practical application for emerging photovoltaic thin film technologies. Atomic force microscopy (AFM) provides unique capabilities for molecular visualization and ultrasensitive …


Integrated Modular Microfluidic System For Forensic Alu Dna Typing, Samuel Kimani Njoroge Jan 2011

Integrated Modular Microfluidic System For Forensic Alu Dna Typing, Samuel Kimani Njoroge

LSU Doctoral Dissertations

Driven by the numerous applications of genome-related research, fully integrated microfluidic systems have been developed that have advanced the capabilities of molecular and, in particular, genetic analyses. A brief overview on integrated microfluidic systems for DNA analysis is given in Chapter 1 followed by a report on micro-capillary electrophoresis (µCE) of Alu elements with laser-induced fluorescence (LIF) detection, in which the monomorphic Alu insertions on the X and Y chromosomes were utilized to detect male DNA in large female DNA background (Y: X = 1:19) without cell sorting prior to the determination. The polymorphic Alu loci with known restricted geographical …


Quality Of Service Based Data-Aware Scheduling, Archit Kulshrestha Jan 2011

Quality Of Service Based Data-Aware Scheduling, Archit Kulshrestha

LSU Doctoral Dissertations

Distributed supercomputers have been widely used for solving complex computational problems and modeling complex phenomena such as black holes, the environment, supply-chain economics, etc. In this work we analyze the use of these distributed supercomputers for time sensitive data-driven applications. We present the scheduling challenges involved in running deadline sensitive applications on shared distributed supercomputers running large parallel jobs and introduce a ``data-aware'' scheduling paradigm that overcomes these challenges by making use of Quality of Service classes for running applications on shared resources. We evaluate the new data-aware scheduling paradigm using an event-driven hurricane simulation framework which attempts to run …


Semiconducting Polymers And Block Copolymers Prepared By Chain-Growth Living Polymerization, Jinwoo Choi Jan 2011

Semiconducting Polymers And Block Copolymers Prepared By Chain-Growth Living Polymerization, Jinwoo Choi

LSU Doctoral Dissertations

Organic semiconducting polymers are the unique materials that considered a basis for the next generation of electronic and optoelectronic applications. However, high device performance of semiconducting polymers strongly depends on their molecular structure and nanoscale organization. Therefore, it is an essential task to develop robust and versatile synthetic approaches to build such well-defined semiconducting polymer materials. This Ph.D. study aimed at design of state-of-the-art synthetic approaches towards organic semiconducting polymers via chain-growth living polymerization as well as development of polymer architectures which can self-organize into supramolecular nanoassemblies or allow external control of the polymer’s properties. First, we prepared a series …


Exotic Ground States: A Study In The Structural Effects On Frustration And Dimensionality, Melissa C. Menard Jan 2011

Exotic Ground States: A Study In The Structural Effects On Frustration And Dimensionality, Melissa C. Menard

LSU Doctoral Dissertations

Structural disorder and dimensionality play central roles in the characterization of structure and properties of crystalline materials. Although structural disorder is commonly considered an undesirable quality, structural disorder may be desirable when searching for new materials with exotic properties. Disorder can be used as a tunable parameter when considering atomic sizes, coordination preferences, and electronegativity differences can be varied by substituting elements into a given structure. Dimensionality can be viewed as another adjustable parameter when searching for new materials presenting unique challenges when characterizing new materials. One way to tune dimensionality is by chemical doping to affect coupling between layers/chains. …


Fragmentation Sensitivity And Its Consequences On Demography And Host-Ectoparasite Dynamics In Amazonian Birds, Erik I. Johnson Jan 2011

Fragmentation Sensitivity And Its Consequences On Demography And Host-Ectoparasite Dynamics In Amazonian Birds, Erik I. Johnson

LSU Doctoral Dissertations

The Amazon rainforest is experiencing rapid deforestation due to ranching, agriculture, and urban development, which often leads to remnant patches serving as refugia for forest organisms. By mist-netting passerines in 11 forest fragments (1-, 10-, and 100-ha patches) and nearby continuous forest at the Biological Dynamics of Forest Fragmentation Project near Manaus, Brazil, I conducted a series of studies to identify mechanisms that drive population changes in fragmented landscapes. First, I examined the age structure of bird populations from six ecological guilds in fragments and continuous forest. Immatures are the dispersing age group in birds, and their relative abundance in …


A Comprehensive Study Of Dust Formation And Evolution In Core Collape Supernovae, Jennifer Erin Andrews Jan 2011

A Comprehensive Study Of Dust Formation And Evolution In Core Collape Supernovae, Jennifer Erin Andrews

LSU Doctoral Dissertations

Detection of large amounts of dust in high redshift galaxies suggests that core collapse supernovae (CCSNe) may play a critical role in the dust budget of galaxies in the early universe, when galaxies are only a few hundred million years old. At an age of only 1Gyr, asymptotic giant branch (AGB) stars may not have had the time to become significant dust contributors, leaving CCSNe as an alternative explanation since they quickly evolve and return their material to the surrounding interstellar medium. For the past three years, I have been observing the CCSNe 2007it and 2007od with Gemini, Hubble Space …


Twisted Frobenius-Schur Indicators For Hopf Algebras, Maria Vega Jan 2011

Twisted Frobenius-Schur Indicators For Hopf Algebras, Maria Vega

LSU Doctoral Dissertations

The classical Frobenius--Schur indicators for finite groups are character sums defined for any representation and any integer $m\ge 2$. In the familiar case $m=2$, the Frobenius--Schur indicator partitions the irreducible representations over the complex numbers into real, complex, and quaternionic representations. In recent years, several generalizations of these invariants have been introduced. Bump and Ginzburg in 2004, building on earlier work of Mackey from 1958, have defined versions of these indicators which are twisted by an automorphism of the group. In another direction, Linchenko and Montgomery in 2000 defined Frobenius--Schur indicators for finite dimensional semisimple Hopf algebras. In this dissertation, …


Preface Dec 2010

Preface

Communications on Stochastic Analysis

No abstract provided.


On The Characteristic Function Of Random Variables Associated With Boson Lie Algebras, Luigi Accardi, Andreas Boukas Dec 2010

On The Characteristic Function Of Random Variables Associated With Boson Lie Algebras, Luigi Accardi, Andreas Boukas

Communications on Stochastic Analysis

No abstract provided.


Cosine And Gaussian Transforms, Carlos Lizama, Rolando Rebolledo Dec 2010

Cosine And Gaussian Transforms, Carlos Lizama, Rolando Rebolledo

Communications on Stochastic Analysis

No abstract provided.


Markov Chains And Dynamical Systems: The Open System Point Of View, Stéphane Attal Dec 2010

Markov Chains And Dynamical Systems: The Open System Point Of View, Stéphane Attal

Communications on Stochastic Analysis

No abstract provided.


Characterization Of Unitary Processes With Independent Increments, Un Cig Ji, Lingaraj Sahu, Kalyan B Sinha Dec 2010

Characterization Of Unitary Processes With Independent Increments, Un Cig Ji, Lingaraj Sahu, Kalyan B Sinha

Communications on Stochastic Analysis

No abstract provided.


How To Differentiate A Quantum Stochastic Cocycle, J Martin Lindsay Dec 2010

How To Differentiate A Quantum Stochastic Cocycle, J Martin Lindsay

Communications on Stochastic Analysis

No abstract provided.


Robin Hudson's Pathless Path To Quantum Stochastic Calculus, David Applebaum Dec 2010

Robin Hudson's Pathless Path To Quantum Stochastic Calculus, David Applebaum

Communications on Stochastic Analysis

No abstract provided.


Quantum Filtering In Coherent States, John E Gough, Claus Köstler Dec 2010

Quantum Filtering In Coherent States, John E Gough, Claus Köstler

Communications on Stochastic Analysis

No abstract provided.


E-Semigroups Subordinate To Ccr Flows, Stephen J Wills Dec 2010

E-Semigroups Subordinate To Ccr Flows, Stephen J Wills

Communications on Stochastic Analysis

No abstract provided.


Transformation Of Quantum Lévy Processes On Hopf Algebras, Michael Schürmann, Michael Skeide, Silvia Volkwardt Dec 2010

Transformation Of Quantum Lévy Processes On Hopf Algebras, Michael Schürmann, Michael Skeide, Silvia Volkwardt

Communications on Stochastic Analysis

No abstract provided.


Quantum Quasi-Markov Processes, L-Dynamics, And Noncommutative Girsanov Transformation, V P Belavkin Dec 2010

Quantum Quasi-Markov Processes, L-Dynamics, And Noncommutative Girsanov Transformation, V P Belavkin

Communications on Stochastic Analysis

No abstract provided.


Plankton Community Respiration And Productivity For The Louisiana Offshore Ecosystem, July 2007 Results, Brandon Michael Boyd Oct 2010

Plankton Community Respiration And Productivity For The Louisiana Offshore Ecosystem, July 2007 Results, Brandon Michael Boyd

Honors Theses

No abstract provided.


Beneath The Salt Marsh Canopy: Loss Of Soil Strength With Increasing Nutrient Loads, R. Eugene Turner Sep 2010

Beneath The Salt Marsh Canopy: Loss Of Soil Strength With Increasing Nutrient Loads, R. Eugene Turner

Faculty Publications

Although the broadly observed increase in nutrient loading rates to coastal waters in the last 100 years may increase aboveground biomass, it also tends to increase soil metabolism and lower root and rhizome biomass—responses that can compromise soil strength. Fourteen different multiyear field combinations of nutrient amendments to salt marshes were made to determine the relationship between soil strength and various nitrogen, phosphorus, and nitrogen+phosphorus loadings. There was a proportional decline in soil strength that reached 35% in the 60- to 100-cm soil layer at the highest loadings and did not level off. These loading rates are equivalent to those …