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Catalysts For The Positional Isomerization Of Internal, Long-Chain Olefins, James Edward Bruno Jan 2015

Catalysts For The Positional Isomerization Of Internal, Long-Chain Olefins, James Edward Bruno

LSU Doctoral Dissertations

Double-bond isomerization of internal C16-C18 olefins is a necessary step in the production of paper sizing agents. In this work, the properties that enable long-lasting solid acid catalysts (both commercial and lab-synthesized) were identified, the efficacy of regenerated solid acid catalysts was tested, and the feasibility of organometallic chain-walking catalysts (both homogeneous and polymer-supported) for olefin isomerization was evaluated. Hexadecene isomerization was investigated using perfluorinated ion exchange resins (Nafion®) supported on SiO2 or Al2O3, sulfonated poly(styrene-co-divinylbenzene) resins (PS-DVBs), tungstated zirconias, and acidic zeolites. Selected catalysts underwent lifetime studies. Oversulfonated PS-DVBs (e.g., Amberlyst 35) were reasonably selective with long lifetimes, only …


Analyses Of The Mec1 Dna Damage Pathway In Saccharomyces Cerevisiae, William Barrett Ainsworth Jan 2015

Analyses Of The Mec1 Dna Damage Pathway In Saccharomyces Cerevisiae, William Barrett Ainsworth

LSU Doctoral Dissertations

Eukaryotic organisms implement conserved surveillance machinery to sense and respond to DNA damage. Fundamental to the repair process is coordinated regulation of repair genes and initiation of cell cycle arrest protocols. Failure to preserve these checkpoints results in accumulation of mutated DNA and aberrant cell phenotypes that are characteristic of human disease. The yeast, Saccharomyces cerevisiae, utilizes the MEC1 checkpoint pathway to regulate the DNA damage response. This study addressed two overarching themes of transcriptional and post-translational regulation within the MEC1 pathway. We first applied our understanding of the MEC1 DNA damage transcriptional response to develop advanced luciferase whole cell …


Aqueous Atmospheric Species, A Dual Study: 1. Comparison Of The Effects Of Temperature, Oxygen Level, Ionic Strength, And Ph On The Reaction Of Benzene With Hydroxyl Radicals At The Air-Water Interface To The Bulk Aqueous Phase. 2. Determination Of Carbonyl Compounds In Fog Water Samples Via Online Concentration And Hplc, Aubrey Anne Heath Jan 2015

Aqueous Atmospheric Species, A Dual Study: 1. Comparison Of The Effects Of Temperature, Oxygen Level, Ionic Strength, And Ph On The Reaction Of Benzene With Hydroxyl Radicals At The Air-Water Interface To The Bulk Aqueous Phase. 2. Determination Of Carbonyl Compounds In Fog Water Samples Via Online Concentration And Hplc, Aubrey Anne Heath

LSU Doctoral Dissertations

The air-water interface is the largest interface in the environment. Atmospheric droplets, such as fog, which can have an exceptionally high surface area-to-volume ratio, also have a large range of physical and chemical properties (e.g. temperature, pH, ionic strength, and chemical composition) based on location, time of day, and emission source. Unlike larger atmospheric droplets, which are predominately characterized by bulk aqueous phase conditions, reactions that take place in fog droplets are determined by both the bulk-aqueous phase and the air-water interface due to a high surface area-to-volume ratio. In order to have a greater understanding of atmospheric processes and …


Ambit Of Multiphase Cfd In Modelling Transport Processes Related To Oil Spill Scenario And Microfluidics, Abhijit Rao Jan 2015

Ambit Of Multiphase Cfd In Modelling Transport Processes Related To Oil Spill Scenario And Microfluidics, Abhijit Rao

LSU Doctoral Dissertations

During the ‘Deepwater Horizon’ accident in the deep sea in 2010, about 4.9 million barrels of oil was released into the Gulf of Mexico, making the spill one of the worst ocean spills in recent times. To mitigate the ill effects of the event on the environment, subsea injection of dispersants was carried out. Dispersant addition lowers the interfacial tension at oil/water interface and presence of local turbulence enhances the droplet disintegration process. The oil droplets contain a plethora of hydrocarbons which are soluble in water. In deep spill scenarios, droplets spend large amounts of time in water column; hence, …


Electrochemical Study Of Ammonium Interaction With Au,Sn And Cu Electrodes In Nonaqueous Electrolytes, Guoying Qu Jan 2015

Electrochemical Study Of Ammonium Interaction With Au,Sn And Cu Electrodes In Nonaqueous Electrolytes, Guoying Qu

LSU Doctoral Dissertations

Nonaqueous electrolytes play an important role in electrochemical devices such as flip chip and lithium-air batteries. In this work, we examine ammonium-Cu, Sn and Li interactions in nonaqueous electrolytes to optimize the future flip chip flux and electrolyte additive of lithium-air battery. The activity of halogen-free carboxylic acid flux is considered one of the most important aspects in controlling flip chip joint quality recently. CuOx removal effectiveness of carboxylic acid solutions at Cu substrates using electrochemical methods at elevated temperatures from 100ºC to 180ºC is studied thoroughly by chronopotentiometry and gravimetric analysis. Carboxylic acid-based solutions with ethanolamine show oxide removal …


Molecular Dynamics Simulation Of The Structure, Dynamics And Crystallization Of Ionic Liquids Under Confinement And Low Temperature, Xiaoxia He Jan 2015

Molecular Dynamics Simulation Of The Structure, Dynamics And Crystallization Of Ionic Liquids Under Confinement And Low Temperature, Xiaoxia He

LSU Doctoral Dissertations

Ionic liquids (ILs) have sparked widespread interest due to their peculiar properties and the resulting possibility of manifold applications. In this dissertation, molecular dynamics (MD) simulations have been used to elucidate the dynamics, structure and crystallization of ionic liquids in the bulk and confinement. First we studied the properties of the ILs [dmim+][Cl-] and [emim+][NTf2-] when they are confined inside nanomaterials such as CMK-3, CMK-5 and an isolated amorphous carbon nanopipe (ACNP). The results indicate that the ions of the ILs form different layers inside these nanomaterials and their dynamics are slower due to the confinement. We also found significant …


Deepwater Gulf Of Mexico Oil Spill Scenarios Development And Their Associated Risk Assessment, Muhammad Zulqarnain Jan 2015

Deepwater Gulf Of Mexico Oil Spill Scenarios Development And Their Associated Risk Assessment, Muhammad Zulqarnain

LSU Doctoral Dissertations

World’s growing energy demand has pushed oil companies to explore and produce hydrocarbons in complex and technologically challenging deepwater environments. These difficult and complex operations involve the risk of major accidents as well, demonstrated by disasters such as the explosion and fire on the UK production platform Piper Alpha and capsizing of the Deepwater Horizon rig in the Gulf of Mexico (GoM). Accidents cause death, suffering, pollution of the environment, disruption of business and bad reputation to oil industry. A quantitative risk analysis technique has been used in this study to identify and categorize risk associated with different life phases …


Bioplastic Production In Cyanobacteria And Consensus Degenerate Pcr Probe Design, Courtney Edward Lane Jan 2015

Bioplastic Production In Cyanobacteria And Consensus Degenerate Pcr Probe Design, Courtney Edward Lane

LSU Doctoral Dissertations

Cyanobacteria show much promise in reducing biodegradable thermoplastic production costs; however, most currently characterized strains are ill-equipped to do so. The result of Objective I produced a high-throughput assay designed to discover existing cyanobacterial strains and rapidly characterize them as PHA-producers or potential PHA-producers. This assay will play an instrumental role in the attainment of a novel cyanobacteria environmental isolate capable of accumulating high levels of PHA naturally. Objective II produced an open source computer program which dramatically speeds the design of similar assays for any arbitrary genetic screening purpose. The program is not limited to this implementation alone. In …


Application Of Discrete Element Method And Computational Fluid Dynamics To Selected Dispersed Phase Flow Problems, Oladapo Olanrewaju Ayeni Jan 2015

Application Of Discrete Element Method And Computational Fluid Dynamics To Selected Dispersed Phase Flow Problems, Oladapo Olanrewaju Ayeni

LSU Doctoral Dissertations

A parallel discrete particle modelling framework (PAR_DPM3D) is applied to study three fundamental multiphase flow problems: The sedimentation of a cluster of particles in a viscous ambient fluid, multiphase flow in a bench-scale fluidized bed and granular segregation and mixing dynamics in a rotating drum. Various phenomena including torus formation and particle cluster breakup are reproduced. We provide new insights into the volume fraction dependence of the dynamic characteristics of a settling particle cluster and find a similar dependence in the simulations as in the theoretical predictions of Nitsche and Batchelor 1. Similarities in the interaction between a system of …


Laboratory Experimental Demonstration Of The Effect Of Oceanic Whitecaps In The Transport Of Oil And Dispersant Components To The Atmosphere, Paria Avij Jan 2015

Laboratory Experimental Demonstration Of The Effect Of Oceanic Whitecaps In The Transport Of Oil And Dispersant Components To The Atmosphere, Paria Avij

LSU Doctoral Dissertations

During the DWH oil spill, vast quantities of crude oil were released into the sea-surface environment of the Gulf of Mexico. There has been ample research focused on the transport of oil into the different environmental sections. Evaporation has been considered to be the only transport pathway of oil spill matter into the atmosphere. However, the aerosolization of oil and dispersant via bursting bubbles as they occur in whitecaps and breaking waves has not been considered in the oil and dispersant budget calculation. This transport vector is significant as it is the dominant source of particulate matter production in the …


A Comprehensive Optimization Framework For Designing Sustainable Renewable Energy Production Systems, Aryan Geraili Nejadfomeshi Jan 2015

A Comprehensive Optimization Framework For Designing Sustainable Renewable Energy Production Systems, Aryan Geraili Nejadfomeshi

LSU Doctoral Dissertations

As the world has recognized the importance of diversifying its energy resource portfolio away from fossil resources and more towards renewable resources such as biomass, there arises a need for developing strategies which can design renewable sustainable value chains that can be scaled up efficiently and provide tangible net environmental benefits from energy utilization. The objective of this research is to develop and implement a novel decision-making framework for the optimal design of renewable energy systems. The proposed optimization framework is based on a distributed, systematic approach which is composed of different layers including systems-based strategic optimization, detailed mechanistic modeling …