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Research On 3d Printing Resin Exposure Properties And Its Application On Centrifugal Microfluidic Platform Based On Fluorescence Detection, Zheng Qiao

LSU Doctoral Dissertations

This dissertation encapsulates significant advancements in the field of SLA 3D printing and centrifugal microfluidics. Central to the research is the development of a novel mathematical model for predicting trapped resin thickness in SLA 3D printing, a groundbreaking contribution that addresses a critical aspect of printing intricate structures. This model, the first to establish a mathematical relationship for resin thickness, is rooted in a comprehensive study of the resin curing process. The research leverages the concept of 'critical dosage' for resin curing, leading to a more refined and theoretically grounded approach for calculating curing thickness. Experimentation further validates the model, …

Investigation Of Gas Dynamics In Water And Oil-Based Muds Using Das, Dts, And Dss Measurements, Temitayo S. Adeyemi

LSU Master's Theses

Reliable prediction of gas migration velocity, void fraction, and length of gas-affected region in water and oil-based muds is essential for effective planning, control, and optimization of drilling operations. However, there is a gap in our understanding of gas behavior and dynamics in water and oil-based muds. This is a consequence of the use of experimental systems that are not representative of field-scale conditions. This study seeks to bridge the gap via the well-scale deployment of distributed fiber-optic sensors for real-time monitoring of gas behavior and dynamics in water and oil-based mud. The aforementioned parameters were estimated in real-time using …

Carbonate Precipitation Behavior In Co2 Mea Electrolyzers With Cu Electrocatalyst, John C. Hendershot

LSU Master's Theses

Annually, over 35 billion metric tons of carbon dioxide (CO₂) are emitted into Earth’s atmosphere. The accumulated CO₂ emissions in the atmosphere over the last century drive climate change. CO₂ electroreduction (CO₂ER) is an emerging technology that aims to recycle carbon emissions from the industrial sector by using CO₂, H₂O, and electricity as a feedstock to produce ethylene (C₂H₄) at current densities as high as 1 A cm^-2 and Faradaic efficiencies (FE) of 60%. However, CO₂ electrolyzers currently demonstrate poor durability at industrially relevant …

Improved Selectivity And Stability In Methane Dry Reforming By Atomic Layer Deposition Onto Ni-Ceo2-Zro2/Al2o3 Catalysts, Jonathan Lucas

LSU Master's Theses

The use of Ni in the dry reforming of methane (DRM) has been widely studied as a replacement for noble metal catalysts (Pt, Pd, Rh) due to Ni’s low cost compared to noble metals, its abundance, and the fact that its DRM activity is near that of noble metal catalysts. However, Ni has been shown to deactivate quickly under DRM conditions. Rare earth oxides such as CeO₂, or as CeO₂-ZrO₂ (CZO) are supports that improve both the activity and stability of Ni DRM systems due to their redox activity. However, this same activity is thought …

A Data-Driven Multivariate Process Monitoring Platform For Knowledge Discovery And Model Building In Industrial Applications, Estelle E. Seghers

LSU Master's Theses

In industrial chemical manufacturing processes, the amount of raw data generated can add complexity in the analysis and understanding of the process dynamics. Being able to properly interpret this data can help improve plant operation, especially regarding safety and profitability. This research has culminated in FastMan-JMP, a platform proposed for monitoring of industrial processes and optimization of the offline data-driven model-building process as part of the process monitoring workflow. FastMan-JMP is a tool developed in Python to apply various data mining and machine learning techniques quickly and easily to better understand valuable patterns and hidden trends in process data. One …

Non-Equilibrium Colloidal Phenomena In Magnetic Fields And Photoillumination: From Controlling Living Microbots To Understanding Microplastics, Ahmed Al Harraq

LSU Doctoral Dissertations

Colloids are a ubiquitous class of materials composed of microscopic particles suspended in a continuous phase which are found in everyday products and in nature. Colloids are also useful models for studying the spontaneous arrangement of matter from individual building blocks to mesophases. Standard treatment of colloid science is based on the assumption of equilibrium conditions, as defined in traditional thermodynamics. However, novel assembly mechanisms and motility are unlocked by pushing colloids away from equilibrium using external energy. In addition, many colloids in nature and in industrial applications exchange energy and mass with the surrounding environment thus behaving in a …

Computational Study Of C-C Coupling Reactions On Heterogeneous Catalysts, Md Saeedur Rahman

LSU Doctoral Dissertations

The utilization of carbon dioxide (CO₂) in chemical production has attracted global research interest. Reacting CO₂ with methane (CH₄) removes these greenhouse gases from the atmosphere and turns both compounds into building blocks for organic compound synthesis. A commonly explored pathway involves dry reforming of methane (DRM), which reacts CH₄ and CO₂ to form syngas, a mixture of H₂ and CO. Syngas is a widely used feedstock for synthesizing chemicals ranging from methanol to fuels via the Fischer-Tropsch (FT) process. However, DRM has a large positive ΔGº, which requires the …

Application Of Distributed Fiber-Optic Sensing For Pressure Predictions And Multiphase Flow Characterization, Gerald Kelechi Ekechukwu

LSU Doctoral Dissertations

In the oil and gas industry, distributed fiber optics sensing (DFOS) has the potential to revolutionize well and reservoir surveillance applications. Using fiber optic sensors is becoming increasingly common because of its chemically passive and non-magnetic interference properties, the possibility of flexible installations that could be behind the casing, on the tubing, or run on wireline, as well as the potential for densely distributed measurements along the entire length of the fiber. The main objectives of my research are to develop and demonstrate novel signal processing and machine learning computational techniques and workflows on DFOS data for a variety of …

Programming The Properties Of Branched Polymers Through Precision Architectures, Michael R. Dearman

LSU Master's Theses

The glass transition of branched polymers is determined by multiple structural parameters that dictate their inter- and intramolecular interactions, and ultimately, their molecular packing in the amorphous phase. Here we examined the impact of side chain length, backbone length, molecular weight composition, and topology on the glass transition behavior of bottlebrush polymers. Through examining precision bottlebrush polymer libraries (PBP, ĐSC = 1.0), we find the infinite molecular weight Tg is reached at a specific brush length after which the effect of the side-chain length dominates. Being a factor more dominant than the backbone, side-chain length affects the Tg of bottlebrush …

Electric Field Driven Co-Assembly And Transport Of Colloids Using Active-Passive Interaction, Brishty Deb Choudhury

LSU Master's Theses

Over the past few decades, the out-of-equilibrium transport and assembly of colloidal particles have been drawing significant interest due to their myriad applications in biology, engineering, and physics. In the absence of any external force, micro and nanoparticles perform Brownian motion in dispersion and are termed as passive colloids. In contrast, active colloids are a class of particles where a net imbalance of fluid flow around their surface drives their net migration in space when subjected to an external electric field. While several studies have shown the ability to program the dynamics of active colloids using an external electric field, …

Bioremediation Of Petroleum-Based Contaminants By Alkane-Degrading Bacterium Alcanivorax Borkumensis, Amber Julaine Pete

LSU Doctoral Dissertations

The world’s dependence on petroleum hydrocarbons has led to significant environmental implications. For example, oil spills cause lasting environmental damage, and the increase of plastics in the marine environment has been growing, specifically, microplastics that can be difficult to detect due to their small size. Petroleum hydrocarbons occur naturally in nearly all marine environments, which has allowed hundreds of microorganisms to evolve to utilize these hydrocarbons as their primary energy source. These microbes are classified as hydrocarbonoclastic and are utilized to remove spilled oil biodegradation. Over the last ten years, progress has been made in the biodegradation of oil spills …

Scale Up Of A Novel Method To Maximize Malonyl-Coa In Escherichia Coli, Clifford Harris Leblanc Iv

LSU Master's Theses

The instability of oil’s price along with its limited availability and impact on the environment motivate the search for an alternative feedstock that can sustain the profitability of chemical companies. Industrial biotechnology can promote renewable sources of energy and products by using microorganisms to produce a wide range of chemical compounds. The three-carbon metabolite, malonyl-CoA, can serve as a precursor to a variety of industrial chemicals. The major hurdle with using malonyl-CoA in industry is that its intracellular concentration in Escherichia Coli is very low. Previous attempts to increase the intracellular level of malonyl-CoA have ranged from genetic engineering of …

Assembly Of Nanostructures At Solid-Liquid And Liquid-Air Interfaces, Yingzhen Ma

LSU Doctoral Dissertations

Molecular and nanoscale colloids such as surfactant, fatty acid and metallic nanoparticles are widely used in numerous applications such as detergents, biomedicine, and catalyst. The assemblies of these colloids show different morphological behavior in aqueous solution due to the wide range of intermolecular interactions such as hydrogen bonding, van der Waals, and electrostatics. The morphology of these assemblies can be changed by environmental factors including temperature, ionic strength, and salinity. However, the guidance to direct assembled state of colloidal assemblies at heterogenous interfaces under various external stimuli remains poorly understand. In this Ph.D. dissertation, we show the adsorption and reconfiguration …

Model-Guided Design Of Rna-Based Synthetic Circuits For The Dynamic Regulation Of Gene Expression, Jordan R. Ryan

LSU Master's Theses

A longstanding goal in synthetic biology has been to build synthetic gene circuits with the ability to harness nature’s capability of precise gene expression regulation. Advancements in RNA technology have established RNA-based regulators with distinct advantages over traditional protein-based regulators such as faster signal propagation, versatile programmability, and low cellular burden, which has created an interest in the field to construct innovative synthetic gene circuits using de novo RNA- based regulators. However, our understanding of the behavior and kinetics of RNA-RNA interactions for the construction of gene circuits is incomplete. This thesis proposes a model-guided design framework that integrates mechanistic …

Directed 3d Chemotaxis Of Cancer Cells In Response To Oscillating Chemical Gradients Using A Microfluidic Device, Trevor R. Thrasher

Honors Theses

No abstract provided.

Tuning Electrochemical Interactions And Polymer Electrolyte Interfaces For Enhanced Organic Acid Separations Using Electrodeionization, Matthew Leo Jordan

LSU Doctoral Dissertations

Chemical separations are critical processes for chemical and industrial plants to purify and isolate products however current separation technologies, such as distillation, rely on energy intensive processes. Electrochemical separation processes, such as electrodialysis and electrodeionization, are an energy efficient alternative that are emerging as an alternative for thermal-based separations. Organic acids are weakly ionizable species and susceptible for purification from process streams using electrochemical processes. Recently the fermentation route has garnered greater attention as a means for producing value-added chemicals, such as organic acids, from a renewable feedstock and aiding the circular economy. Some of the challenges electrodialysis faces for …

Computational Study Of The Reactions Of Heteroatomic Compounds On Ceo2, Suman Bhasker Ranganath

LSU Doctoral Dissertations

The mechanisms of ambient-temperature reactions of heteroatomic compounds catalyzed by ceria (CeO₂), an archetypical reducible oxide, for enzyme mimetics, environmental protection, and chemical synthesis are investigated in this dissertation using theoretical methods. CeO₂ is modeled with thermodynamically stable low-index surfaces exposed by commonly studied ceria thin films and nano particles. To understand phosphatase-like dephosphorylation activity, stable adsorption states and surface reactions of model phosphates are examined. Binding of the central P-atom to surface lattice oxygen (O_latt) supplemented by phosphoryl O-Ce interaction is the only stable adsorption state for the un-dissociated molecule. Deprotonation of phosphate monoesters, …

Heteroaggregation Of Lignin-Zein Nanoparticles: Effects Of Relative Size And Concentration, Yada Chulakham

LSU Master's Theses

Nanotechnology has become an advanced tool for manufacturing materials of the future. As the size of a material is reduced to a nanoscale, its surface area to volume ratio increases drastically, and its surface property becomes size dependent. This allows scientists to make use of unique properties that nanomaterials have to offer to create novel materials that otherwise could not have been achieved in meter-scale materials. As more industrial companies have planned to incorporate different types of nanomaterials into their products, it is undeniable that some of these nanomaterials will be released to the environment. Such possibility has led to …

Application Of Gravity Data For Hydrocarbon Exploration Using Machine Learning Assisted Workflow, Oluwafemi Temidayo Alaofin

LSU Master's Theses

Gravity survey has played an essential role in many geoscience fields ever since it was conducted, especially as an early screening tool for subsurface hydrocarbon exploration. With continued improvement in data processing techniques and gravity survey accuracy, in-depth gravity anomaly studies, such as characterization of Bouguer and isostatic residual anomalies, have the potential to delineate prolific regional structures and hydrocarbon basins. In this study, we focus on developing a cost-effective, quick, and computationally efficient screening tool for hydrocarbon exploration using gravity data employing machine learning techniques. Since land-based gravity surveys are often expensive and difficult to obtain in remote places, …

Cfd Simulations Of Macroscopic And Microscopic Multiphase Fluid Flow And Droplet Interaction, Aaron Harrington

LSU Master's Theses

Multiphase flow is a complex phenomenon which can be modeled on numerous different length scales, both macroscopically and microscopically. The use of a Euler-Euler model for Computation Fluid Dynamics (CFD) simulations of subcooled boiling phenomena is discussed in detail. The CFD conditions have been set up to mimic previous experimental conditions. A cylindrical vessel with subcooled liquid flow is heated along part of the axial wall of the vessel. A constant heat flux is applied to produce subcooled boiling. We discuss the development of the phase change within the vessel as well as the temperature profile, and validate the results …

Investigating Black Silicon Surface Geometry Via Parameter Modification And Low Flow Inductively Coupled Plasma Deep Reactive Ion Etching, Noah Mulherin Smith

Honors Theses

No abstract provided.

Engineering The Surface Of Fe3o4 Nanoparticles For Catalytic And Magnetic Applications, Natalia Da Silva Moura

LSU Doctoral Dissertations

With the rapid depletion of the U.S. energy resources coupled with population growth, heat management technologies must be improved to sustain our quality of life. Precisely, in catalysis, it is estimated that only ~50% of the energy supplied to the reactor is used for product conversion due to dissipation losses. Among the emerging technologies with a promising reduction in heat losses is induction heating, offering targeted heat delivery with magnetic nanoparticles. Under alternating magnetic fields (AMF), these nanoparticles can absorb the energy from Radio-Frequency (RF) fields and dissipate it as heat on the nanoparticle surface. This in situ heat generation …

Direct Activation Of Light Alkanes To Value-Added Chemicals Using Supported Metal Oxide Catalysts, Md Ashraful Abedin

LSU Doctoral Dissertations

One of the most challenging aspects of modern-day catalysis is the conversion of methane. Direct conversion of methane via dehydroaromatization (MDHA) is a well-known process which can produce valuable hydrocarbons. Mo oxide supported on ZSM-5/MCM-22 has been studied extensively in recent years for MDHA. Mo carbides are responsible for activating methane by forming CHx species. These are dimerized into C2Hy and oligomerized on ZSM-5/MCM-22 Brønsted acid sites to form aromatics. Sulfated zirconia (SZ) supported Mo catalyst contains the acid sites necessary to produce benzene in MDHA. Here, sulfated hafnia (SH), a homologous oxide like SZ, has been proposed to provide …

Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent, Bulbul Ahmed

LSU Master's Theses

Hemp is considered as one of the sustainable agricultural fiber materials. Degumming or surface modification of hemp bast is needed to produce single fibers for ensuing textile and industrial applications. The traditional degumming process necessitates a high amount of alkali, which causes detrimental environmental pollution. This study offers a new method to degum hemp fibers with reduced use of harmful alkali and precious water resources. In this work, hemp bast fibers were degummed by using combined microwave energy and deep eutectic solvent (DES). The properties of hemp fibers manufactured by this method were investigated and compared with the traditional alkali …

Gas Evolution Phenomenon Of Methane In Base Fluids Of Non-Aqueous Drilling Muds Under Controlled Depressurization, Damilola Ojedeji

LSU Master's Theses

As wells become more complex and drilling conditions to reach targets prove even more challenging, being able to detect influx event early and safely handle these influxes has become one of the most important focus areas for improvement in well control safety. The high solubility of formation gas in non-aqueous drilling fluids however makes kick detection and safe handling of kicks more complicated. Recent studies are beginning to incorporate desorption kinetics in well control models to simulate the transient multiphase flow phenomenon associated with gas kicks in non-aqueous drilling fluids to foster safe handling of kicks. However, there is currently …

Enhanced Oil Recovery In Tight Rocks Using The “Slot-Drill” Completion, Hassan Amer

LSU Master's Theses

Enhanced oil recovery (EOR) is essential in shale/tight formations because primary recovery typically produces less than 10% of the original hydrocarbon in-place (OHIP). This work presents a novel “slot-drill” EOR technology, which involves injecting gas through a horizontal fracture that is cut into the formation near the top of the reservoir (using a tensioned abrasive cutting cable mounted to the drillstring) and producing oil from a second slot-drilled horizontal fracture near the bottom of the reservoir.

The dusty-gas diffusion model was implemented in a compositional simulator to account for the diffusion mechanism expected during the injection of gases in this …

Blowout - Capping - Fracturing - Relief Well, A Full Cycle Workflow, Youssuf A. Elnoamany

LSU Master's Theses

Broaching is defined as the uncontrolled release of hydrocarbons to ocean seafloor after a loss of subsurface well control event. Failed attempts to cap the offshore wells undergoing worst case discharge may lead to hydraulic fracture initiation and subsequent propagation, leading to renewed release of hydrocarbon to the seafloor. During the capping stack shut-in process, pressure build-up will occur along the wellbore, exposing locations of possible fracture initiation to overpressurized fluid, such as directly below the casing shoe, and critical points along the well casing. Shall there be enough build-up pressure to exceed the minimum horizontal stress in an exposed …

Controlling The Orientation Of Fluorescent Dyes Using External Electric Fields, Henry J. Kantrow

Honors Theses

No abstract provided.

High Temperature Polymer Electrolytes For Hydrogen Fuel Cells And Electrochemical Pumps, Gokul Venugopalan

LSU Doctoral Dissertations

Hydrogen fuel cell and separation technologies such as proton exchange membrane fuel cells (PEMFCs) and electrochemical hydrogen pump (ECHP) offer a profound advantage in the transition to a low-carbon economy. An imperative hitch in hydrogen fuel cells and ECHP technology has been the electrocatalyst poisoning by carbon monoxide (CO) and other contaminants in the reactant mixture. By operating, hydrogen fuel cells and ECHPs at high temperatures (>200 °C), the effect of CO adsorption on the electrocatalyst surface could be curtailed. The high-temperature operation of devices necessitates a proton exchange membrane (PEM) to operate under anhydrous conditions.

In this work, …

Adsorption And Transport Of Colloids At Interface And In Bulk, Jingyun Lee

LSU Doctoral Dissertations

Colloids are suspensions of microscopic insoluble particles dispersed in a continuum phase such as liquid or gas. Colloids are found in our everyday life from food and cosmetic industries to pharmaceutical and biomedical applications. Depending on a global minimum of the free-energy landscape, colloidal suspensions can be classified as two major classes: equilibrium or active colloidal system. This Ph.D dissertation presents strategies to engineer equilibrium self-assembled structures and out-of-equilibrium active matter using various interparticle forces.

First, we introduce the means to promote the equilibrium self-assembled structures driven by adsorption of colloids at interface. Typically, adsorption of colloids at interface is …