Engineering Commons^™

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 …

Lyapunov-Based Economic Model Predictive Control For Detecting And Handling Actuator And Simultaneous Sensor/Actuator Cyberattacks On Process Control Systems, Henrique Oyama, Dominic Messina, Keshav Kasturi Rangan, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

The controllers for a cyber-physical system may be impacted by sensor measurement cyberattacks, actuator signal cyberattacks, or both types of attacks. Prior work in our group has developed a theory for handling cyberattacks on process sensors. However, sensor and actuator cyberattacks have a different character from one another. Specifically, sensor measurement attacks prevent proper inputs from being applied to the process by manipulating the measurements that the controller receives, so that the control law plays a role in the impact of a given sensor measurement cyberattack on a process. In contrast, actuator signal attacks prevent proper inputs from being applied …

Lyapunov-Based Economic Model Predictive Control For Online Model Discrimination, Henrique Oyama, Helen Durand

Chemical Engineering and Materials Science Faculty Research Publications

Economic model predictive control (EMPC) is a flexible control design strategy that can be modified to achieve many operating goals while also ensuring safe operation (e.g., by adding Lyapunov-based stability constraints to form Lyapunov-based EMPC, or LEMPC). Prior works have investigated LEMPC capabilities for achieving goals online beyond optimizing process economics, including aiding in model structure selection to benefit model-based control system design since the accuracy and quality of the process model are important for achieving an expected performance from such systems. This work further probes the capabilities of LEMPC to accomplish multiple objectives during process operation, including aiding in …

Impact Of Polymer Rheology On Gel Treatment Performance Of Horizontal Wells With Severe Channeling, Jianqiao Leng, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Gel treatment has been a cost-effective method to control the conformance of a reservoir with severe heterogeneity problems. The water channels in such reservoirs can be classified as open fractures or high permeability porous media with pore-throat network. Many simulation studies have been conducted to discuss gel treatment performance for conformance control. However, nobody considered the polymer rheology difference in open fractures and porous media in simulation. Previous simulation studies also ignored the residual resistance factor as a function of rock permeability rather than a constant parameter. In this study, a conceptual simulation model was established to simulate the linear …

In-Situ Generation Of Hydrocarbons From Kerogen Using Electromagnetic Radiation, Forrest Green

Graduate Theses & Non-Theses

From using surface seeps to modern day exploitation of hydrocarbon source rocks, the petroleum industry is awaiting the next big innovation, accelerated kerogen conversion. In the industry’s history, electromagnetic radiation (EMR) has been used for exploration and now it will be taken to the extreme by determining an effective and efficient method to synthetically generate readily available hydrocarbons. The study starts with examining and defining what kerogen is and its importance as a source material. A strong understanding of what kerogen is, and an analysis of other in-situ projects presents an opportunity to study the finer details of kerogen’s conversion …

Modelling And Validation Of A Gas-Solid Fluidized Bed Using Advanced Measurement Techniques, Sebastián Uribe, Haidar Taofeeq, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

With a Euler-two-phase (E2P) approach, through computational fluid dynamics (CFD) techniques, a mathematical model for the prediction of the local hydrodynamic behavior of a gas-solid fluidized bed was implemented. Simulations are conducted for a fluidized bed of 0.14 m internal diameter packed with Gerdart B glass beads particles, with an average diameter of 365 μm, at dimensionless inlet velocities ranging from (Formula presented.). The implemented model considers the multiphase and multiscale interactions through the inclusion of three sub-models, which allows the model to have a broad range of applicability. Predictions were compared against experimental measurements reported on previous contributions for …

Integrated Direct Air Capture And Oxidative Dehydrogenation Of Propane With Co2 At Isothermal Conditions, Shane Lawson, Khaled Baamran, Kyle Newport, Turki Alghamadi, Gary Jacobs, Fateme Rezaei, Ali A. Rownaghi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Developing routes of utilizing CO₂ emissions is important for long-term environmental preservation, as storing such emissions underground will eventually become unsustainable. One way of utilizing CO₂ emissions is as a light-oxidant feedstock for oxidative dehydrogenation of propane (ODHP) to propylene. However, the adsorption and reaction steps typically occur at widely different temperatures, meaning that the thermal gradients – and by extension process energy requirements – are often unreasonably high. In recent years, dual-functional materials (DFMs) – i.e., materials comprised of a high temperature adsorbent phase alongside a heterogeneous catalyst – have been employed for combined CO₂ adsorption …

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

Honors Capstones

No abstract provided.

Rapid Removal Of Pfoa And Pfos Via Modified Industrial Solid Waste: Mechanisms And Influences Of Water Matrices, Hongyi Wan, Rollie Mills, Kai Qu, James C. Hower, M. Abdul Mottaleb, Dibakar Bhattacharyya, Zhi Xu

Chemical and Materials Engineering Faculty Publications

Emerging perfluoroalkyl and polyfluoroalkyl substances contaminate waters at trace concentrations, thus rapid and selective adsorbents are pivotal to mitigate the consequent energy-intensive and time-consuming issues in remediation. In this study, coal combustion residuals-fly ash was modified (FA-SCA) to overcome the universal trade-off between high adsorption capacity and fast kinetics. FA-SCA presented rapid adsorption (teq = 2 min) of PFOX (perfluorooctanoic acid and perfluorooctanesulfonic acid, collectively), where the dynamic adsorption capacity (qdyn = qm/teq) was 2–3 orders of magnitude higher than that of benchmark activated carbons and anion-exchange resins. Investigated by advanced characterization and kinetic models, the fast kinetics and superior …

Highly Active And Stable Low-Pgm And Pgm-Free Catalysts For Anion Exchange Membrane Fuel Cells, Horie Adabi Firouzjaie

Theses and Dissertations

Anion exchange membrane fuel cells (AEMFCs) have recently seen significant growth in interest as their achievable current density, peak power density, and longevity have been dramatically improved. Though these advances in performance have been important for demonstrating the feasibility of the technology, nearly all AEMFCs reported in the literature have required a relatively high loading of platinum group metal (PGM)- based catalysts at both the anode and cathode electrodes. However, to take command of the low-temperature fuel cell market, AEMFCs cannot simply reach the same performance as incumbent proton exchange membrane fuel cells (PEMFCs), which have had decades of development …

Possible Storage Of Co₂ In Saline Aquifer: Storage Factor Estimation, Sarah Abdul Aziz Al-Tamimi

Theses

The objective of this study is to perform laboratory measurements and a CO₂ underground storage study to cover the knowledge gap on CO₂-Brine relative permeability and assess various variables on the storage of CO₂ in a selected aquifer. Several factors that affect CO₂ storage have been discussed in the literature. These include both macroscopic and microscopic displacement efficiency of brine as a function of CO₂ pore volume injected. It is clear from the literature that there is still more work needed to investigate the effect of various variables such as formation temperature, brine viscosity, and the possible presence of free …

Application Of Red Cabbage Anthocyanins As Ph-Sensitive Pigments In Smart Food Packaging And Sensors, Reza Abedi-Firoozjah, Shima Yousefi, Mahshid Heydari, Faezeh Seyedfatehi, Shima Jafarzadeh, Reza Mohammadi, Milad Rouhi, Farhad Garavand

Research outputs 2022 to 2026

Anthocyanins are excellent antioxidant/antimicrobial agents as well as pH-sensitive indicators that provide new prospects to foster innovative smart packaging systems due to their ability to improve food shelf life and detect physicochemical and biological changes in packaged food. Compared with anthocyanins from other natural sources, red cabbage anthocyanins (RCAs) are of great interest in food packaging because they represent an acceptable color spectrum over a broad range of pH values. The current review addressed the recent advances in the application of RCAs in smart bio-based food packaging systems and sensors. This review was prepared based on the scientific reports found …

Visible Light Illuminated Tin Oxide-Gold Nanoparticle Schottky Junctions For H2o2 Generation In Water, Sarah Glass

Honors Capstones

No abstract provided.

Observing And Modeling Water Electrolysis Performance Limitations Attributed To Gas Generation And Porous Media Properties, Joseph S. Lopata

Theses and Dissertations

Water electrolysis has been a simple method of hydrogen production for over two centuries, but the exploration of its nuances is still accelerating. This work compiles numerous mechanisms via which electrolysis efficiency is influenced by phenomena that occur within, adjacent to, and nearby functional porous media. Computational and experimental methods are applied to electrolysis systems to quantify the impact of twophase flow patterns and porous media properties on energy losses, primarily those linked directly to the presence of the gas phase.

First, an introduction to the chemistry and operating principle of water electrolysis is presented and relevant works from the …

Rational Synthesis Of Ultra-Small And Durable Platinum-Based Catalysts For Renewable Energy Applications, Fahim Bin Abdur Rahman

Theses and Dissertations

Ultrasmall supported platinum nanoparticles (Pt NPs) are often used in two promising renewable energy production technologies – hybrid-sulfur water splitting for actively catalyzing H2SO4 decomposition and in fuel cells for the oxygen reduction reaction (ORR). However, the stability of Pt NPs under reaction conditions is the ultimate challenge for these processes. Two prevalent ways to overcome this challenge are improving stability by anchoring Pt onto a secondary metal or doping heteroatoms into the support. This dissertation covers the rational design, synthesis, and stabilization of Pt-based catalysts in these two ways to achieve durable catalytic performance with desired activity and selectivity. …

First-Principles Based Heterogeneous Catalyst Design For Energy Conversion And Plastics Upcycling Processes, Kyung-Eun You

Theses and Dissertations

Replacing scarce and expensive Pt-group metals (Pt, Pd, Ir, Rh, and Ru) commonly used in heterogeneous catalysis with earth-abundant and inexpensive materials is an important challenge to achieve sustainability

The main focus of the first project is to develop highly selective non-precious metal catalysts for the hydrodeoxygenation (HDO) of biomass-derived polyols and we chose to examine the HDO of glycerol and its deoxygenated reaction products (1,2- and 1,3- propanediol) over Cu modified Mo₂C (Cu/Mo₂C) catalysts. In this study, we combined experimental and density functional theory (DFT) results to reveal that the Cu modifier can significantly reduce …

Fundamentals Of Adsorption And Large Scale Pressure Swing Adsorption (Psa) Process Design, Huan Jiang

Theses and Dissertations

This work focused on both fundamental of adsorption and large-scale PSA design. Chapter 1 and 2 addressed the analysis of conditions for formation of adsorption azeotropes in binary systems. Chapter 1 theoretically assessed the necessary and sufficient conditions for the formation of an adsorption azeotrope in a binary gas mixture when this mixture exhibits either intersecting or non-intersecting single gas isotherms. Chapter 2 confirmed theoretically whether adsorption azeotropes can form in a binary mixture at a pressure below the intersection pressure of the corresponding single gas isotherms. Analytical expressions derived for both general and dual thermodynamically consistent process Langmuir (DPL) …

Synthesis, Characterization And Evaluation Of Dilute Limit Alloy Bimetallic Catalysts For Bio-Oil Upgrading, Leandro Tagum De Castro

Theses and Dissertations

Well-defined single-atom catalytic sites with unique geometric and electronic properties are at the forefront of catalyst research. One type of SAC is a so-called dilute limit alloy (DLA), where single metal atom sites are supported on (or in) the surface of a second metal. This category of well-dispersed atoms alloyed on a metal surface has shown to be effective in reactions like selective hydrogenation of alkynes and dienes to alkenes, ethanol dehydrogenation, and the Ullmann reaction of aryl chlorides. In biomass conversion, this type of catalyst may find its way to address and improve conversion and yield that are crucial …

Catalytic Cracking Of Oxygenated Polymer Waste Via Zeolite Catalysts, Andrew Jaeschke

Theses and Dissertations

Plastic recycling has been a prevalent issue since the commercialization of plastics due to lack of adoption and insufficient technology. There are many different types of plastics used in modern day society; however, majority of recycling efforts are focused solely on polyethylene terephthalate (PET) and polyethylene plastics. Some of these overlooked plastics include polyols and polyurethanes, which can be found in a variety of applications including furniture stuffing, adhesives, and insulation foams. Recently, plastic research has turned to catalytic cracking units as a means of plastic recyclability. Catalytic cracking of hydrocarbons is a field dominated by zeolites catalysts, especially ZSM-5. …

Date-Leaf Carbon Particles For Green Enhanced Oil Recovery, Bashirul Haq, Md Abdul Aziz, Dhafer Al Shehri, Nasiru Salahu Muhammed, Shaik Inayath Basha, Abbas Saeed Hakeem, Mohammed Ameen Ahmed Qasem, Mohammed Lardhi, Stefan Iglauer

Research outputs 2022 to 2026

Green enhanced oil recovery (GEOR) is an environmentally friendly enhanced oil recovery (EOR) process involving the injection of green fluids to improve macroscopic and microscopic sweep efficiencies while boosting tertiary oil production. Carbon nanomaterials such as graphene, carbon nanotube (CNT), and carbon dots have gained interest for their superior ability to increase oil recovery. These particles have been successfully tested in EOR, although they are expensive and do not extend to GEOR. In addition, the application of carbon particles in the GEOR method is not well understood yet, requiring thorough documentation. The goals of this work are to develop carbon …

Thermochemical Conversion Of Lipid-Extracted Algal Biomass To Value-Added Sustainable Products, Magdalini Tsarpali

USF Tampa Graduate Theses and Dissertations

The extensive use of fossil fuels has increased the CO2 emissions, a phenomenon that has increased the demand for renewable energy and resources. Algae, photosynthetic aquatic organisms, have recently caught attention due to their high growth rate and the high CO2 capture ability. Biofuels and bioproducts from algae are considered promising alternatives because of their lower carbon footprint. Lipids are by far the most popular algal product, as they find applications in both fuels, such as biodiesel, and products, such as nutraceuticals and cosmetics. However, after lipid extraction, conversion of the residual algal biomass to value-added products is viewed as …

High-Octane Gasoline Production Processes Using Catalysts Containing Platinum, Dilnoza Mauletbayevna Ametova, Duysenbay Xojabayevich Abdikamalov, Edil Abilov

Karakalpak Scientific Journal

The catalytic reforming process is designed to increase the detonation resistance of gasolines and to obtain individual aromatic hydrocarbons, mainly benzene, toluene, xylenes - petrochemical feedstocks. It is important to obtain a cheap hydrogen-containing gas in the process for use in other hydrocatalytic processes. The importance of catalytic reforming processes in oil refining increased significantly in the 1990s. due to the need to produce unleaded high-octane gasoline

Development Of Enhanced Algae Strains And Sustainable Cultivation Processes For Production Of Algal Lipids For Biofuels And Bioproducts, Enlin Lo

USF Tampa Graduate Theses and Dissertations

The establishment of an algae industry is crucial for addressing global biofuel and bioproduct demand that meets the Sustainable Development Goals (SDG) worldwide. Photosynthetic microalgae are excellent sources for food, fiber, fuel, feed, and fertilizer, which are the 5Fs of the SDG. However, at present, algae-based materials are not cost-competitive or sufficiently sustainable. Improved productivity, lower cultivation cost, and reduced use of resources are required to transition from lab to industry, necessitating the development of superior strains that have high productivity and can tolerate environmental stress, such as temperature and salinity, so they can be cultivated at large scale outdoors …

In Situ Characterization Of Electrode Structure And Catalytic Processes In The Electrocatalytic Oxygen Reduction Reaction, Ya-Chen Feng, Xiang Wang, Yu-Qi Wang, Hui-Juan Yan, Dong Wang

Journal of Electrochemistry

As an electrochemical energy conversion system, fuel cell has the advantages of high energy conversion efficiency and high cleanliness. Oxygen reduction reaction (ORR), as an important cathode reaction in fuel cells, has received extensive attention. At present, the electrocatalysts are still one of the key materials restricting the further commercialization of fuel cells. The fundamental understanding on the catalytic mechanism of ORR is conducive to the development of electrocatalysts with the enhanced activity and high selectivity. This review aims to summarize the in situ characterization techniques used to study ORR. From this perspective, we first briefly introduce the advantages of …

In-Situ/Operando57Fe Mössbauer Spectroscopic Technique And Its Applications In Nife-Based Electrocatalysts For Oxygen Evolution Reaction, Jafar Hussain Shah, Qi-Xian Xie, Zhi-Chong Kuang, Ri-Le Ge, Wen-Hui Zhou, Duo-Rong Liu, Alexandre I. Rykov, Xu-Ning Li, Jing-Shan Luo, Jun-Hu Wang

Journal of Electrochemistry

The development of highly efficient and cost-effective electrocatalysts for the sluggish oxygen evolution reaction (OER) remains a significant barrier to establish effective utilization of renewable energy storage systems and water splitting to produce clean fuel. The current status of the research in developing OER catalysts shows that NiFe-based oxygen evolution catalysts (OECs) have been proven as excellent and remarkable candidates for this purpose. But it is critically important to understand the factors that influence their activity and underlying mechanism for the development of state-of-the-art OER catalysts. Therefore, the development of in-situ/operando characterizations is urgently required to detect key intermediates along …

Hydrogen Flooding Of A Coal Core: Effect On Coal Swelling, Stefan Iglauer, Hamed Akhondzadeh, Hussein Abid, Adriana Paluszny, Alireza Keshavarz, Muhammad Ali, Ausama Giwelli, Lionel Esteban, Joel Sarout, Maxim Lebedev

Research outputs 2022 to 2026

Hydrogen is a clean fuel which has the potential to drastically decarbonize the energy supply chain. However, hydrogen storage is currently a key challenge; one solution to this problem is hydrogen geo-storage, with which very large quantities of H2 can be stored economically. Possible target formations are deep coal seams, and coal permeability is a key parameter which determines how fast H2 can be injected and withdrawn again. However, it is well known that gas injection into coal can lead to coal swelling, which drastically reduces permeability. We thus injected H2 gas into a coal core and measured dynamic permeability, …

Photo-Induced Drug Release From Polymeric Micelles And Liposomes: Phototriggering Mechanisms In Drug Delivery Systems, Najla M. Salkho, Nahid S. Awad, William G. Pitt, Ghaleb A. Husseini

Faculty Publications

Chemotherapeutic drugs are highly effective in treating cancer. However, the side effects associated with this treatment lower the quality of life of cancer patients. Smart nanocarriers are able to encapsulate these drugs to deliver them to tumors while reducing their contact with the healthy cells and the subsequent side effects. Upon reaching their target, the release of the encapsulated drugs should be carefully controlled to achieve therapeutic levels at the required time. Light is one of the promising triggering mechanisms used as external stimuli to trigger drug release from the light-responsive nanocarriers. Photo-induced drug release can be achieved at a …

Microcystin-Lr Removal From Water Via Enzymatic Linearization And Ultrafiltration, Abelline Fionah, Cannon Hackett, Hazim Aljewari, Laura Brady, Faisal Alqhtani, Isabel C. Escobar, Audie K. Thompson

Chemical Engineering Faculty Publications and Presentations

Microcystin-LR (MC-LR) is a toxin produced by cyanobacteria that can bloom in freshwater supplies. This study describes a new strategy for remediation of MC-LR that combines linearization of the toxin using microcystinase A, MlrA, enzyme with rejection of linearized byproducts using membrane filtration. The MlrA enzyme was expressed in Escherichia coli (E. coli) and purified via a His-tag with 95% purity. Additionally, composite membranes made of 95% polysulfone and 5% sulfonated polyether ether ketone (SPEEK) were fabricated and used to filter a solution containing cyclic and linearized MC-LR. Tests were also performed to measure the adsorption and desorption of MC-LR …

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 …

A Comparison Of Square-Wave Voltammetry Models To Determine The Number Of Electrons Exchanged In Metal Deposition, Ranon Fuller, Tyler Williams, Mark H. Schvaneveldt, Devin Rappleye

Faculty Publications

A comparison of square-wave voltammetry models for calculating the number of electrons exchanged in a metal deposition reaction. Experiments were conducted for silver deposition on platinum in an aqueous HNO₃ solution and for nickel and lanthanum deposition on platinum in molten LiCl. Diffusion coefficients for Ni²⁺ and La³⁺ in LiCl at 700^oC are calculated. Accuracy of soluble-soluble models versus a soluble-insoluble model is discussed. A simple method for determining the number of electrons exchanged under the constraint of well-compensated ohmic drop is proposed and evaluated.