Chemical Engineering Commons^™

Unveiling The Indoor Performance Of Perovskite/Silicon Tan‑Dem Solar Cells: A Comprehensive Exploration Through Numerically Modelled Energy Band Diagrams, Ziad Khalifa, Sameh O. Abdellatif, Alexander De-Bernardinis, Muath Alkadi, Mostafa Ganoud, Saif Qaid

Chemical Engineering

This paper delves into the indoor performance analysis of Perovskite/Silicon Tandem Solar Cells (PSSTC) through a detailed exploration utilizing numerically modeled energy band diagrams. The primary objective is to uncover the potential of PSSTC for solar energy conversion in indoor settings. Various tandem cell configurations are scrutinized under diverse artificial lighting spectra, with an innovative Li4Ti5O12/ CsPbCl3/MAPbBr3/CH3NH3PbI3/ Si architecture achieving an exceptional maximum power conversion efficiency of 25.25%. This represents a substantial efficiency enhancement of nearly 7% compared to standalone Silicon cells. The study underscores the significance of design optimization in maximizing performance. The energy band diagram analysis reveals a …

Voltammetric Determination Of Hydrogen Peroxide At Decorated Palladium Nanoparticles/Poly 1,5- Diaminonaphthalene Modified Carbon-Paste Electrode, Ziad Khalifa, Mohamed Fathi Abo Oura, Magdi Abdelazzem, Ablah Hathoot

Chemical Engineering

In this work, palladium nanoparticles (PdNPs)/p1,5-DAN/ carbon paste electrode (CPE) and p1,5-DAN/CPE sensors have been developed for determination of hydrogen peroxide. Both sensors showed a highly sensitive and selective electrochemical behaviour, which were derived from a large specific area of poly 1,5 DAN and super excellent electroconductibility of PdNPs. PdNPs/p1,5-DAN/CPE exhibited excellent performance over p1,5-DAN/CPE. Thus, it was used for detecting hydrogen peroxide (H2O2) with linear ranges of 0.1 to 250 μM and 0.2 to 300 μM as well as detection limits (S/N= 3) of 1.0 and 5.0 nM for square wave voltammetry (SWV) and cyclic voltammetry (C.V) techniques, respectively. …

Optogenetic Control Of Bacterial Dormancy, Yousr Dhaouadi Khattab

Dissertations - ALL

The presence of persister cells makes it difficult to eradicate chronic bacterial infections as these dormant subpopulations arise with exposure to stressors and are capable of surviving antimicrobials that target active cells. Persisters can also revert back to normal growing cells when stressors are removed thus reestablishing the infection. It is therefore important to understand the underlying mechanisms of persister formation, as well as wake-up, and target these systems in order to treat chronic bacterial infections. The formation of persisters, however, remains elusive as there is not yet a clear relationship between the various stages of dormancy. Persister cells can …

Chemistry And Processing Of Carbon/Carbon Composites From Furan-Based Polybenzoxazine Resins, Michael Chauby

Theses and Dissertations

Carbon/carbon (C/C) composites are valuable for applications requiring structural integrity at high temperatures. However, their widespread use is limited by high manufacturing costs. Monofunctional furan-based benzoxazine resins were identified as promising candidates for enhancing fabrication efficiency due to their low viscosity, high char yield, and high carbon density. A benzoxazine monomer synthesized from furfurylamine, formaldehyde, and benzyl alcohol (Bz-FA-H) exhibits a crosslinking reaction between the furan group and the hydroxymethyl para substituent on the phenol, not found with other monomers. An investigation using blends of monomers containing Bz-FA-H at various concentrations showed that increasing crosslink density resulted in increased bulk …

Quantifying The Impact Of Microstructure Variation On Charging Capability In Lithium-Ion Batteries, Hunter Teel, Taylor R. Garrick, Mitchell A. Sepe, Joseph S. Lopata, Srikant Srinivasan, Fengkun Wang, Yangbing Zeng, Sirivatch Shimpalee

Faculty Publications

Through the use of electrochemical simulations, variation in the local onset of lithium plating can be predicted and used to set charging guidelines to reduce the risk of lithium plating. The pseudo-two-dimensional (P2D) model is typically used for capturing this behavior; however, it only provides a global lithium plating onset estimate and does not consider the local variation. With material properties translated to an average continuum value, the P2D model can simulate rapid charge and capture global onset of lithium plating. However, this model lacks the ability to resolve localized behaviors across individual components due to local non-uniformities. Our three-dimensional …

Consistent Intraocular Pressure Reduction By Solid Drug Nanoparticles In Fixed Combinations For Glaucoma Therapy, Da Huang, Pedro Norat, Lin Qi, Anna Chernatynskaya, James D. Cole, Vimalin Jeyalatha Mani, Lei Xu, Xiaorong Liu, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Efficient topical drug delivery remains a significant challenge in glaucoma management. Although nanoparticle formulations offer considerable promise, their complex preparation processes, co-delivery issues, and batch consistency have hindered their potential. A scalable fabrication strategy is developed here for preparing solid drug nanoparticles (SDNs) with enhanced drug delivery efficiency. Utilizing hydrophobic antiglaucoma drugs brimonidine (BM) and betaxolol (BX), uniform fixed combination BM/BX SDNs are fabricated through a continuous process, improving batch-to-batch consistency for combined glaucoma treatment. With trehalose being used as a lyoprotectant, BM/BX SDNs can be stored as dry powder and easily reconstituted in phosphate buffered saline. Importantly, reconstituted BM/BX …

Beyond Measures Of Speed & Accuracy: Evaluating Visualization Perception, Reasoning & Decision-Making, Melanie Bancilhon

McKelvey School of Engineering Graduate Student Theses & Dissertations

Visualizations have long been used to support decision-making across various fields. By transforming complex data into graphical representations, such as charts, graphs, and maps, visualizations are generally reputed to make information more accessible and comprehensible for all. While prior work demonstrates that visualizations can improve speed and accuracy across comprehension and analytical tasks, there lacks research on how they can benefit decision-making. Decision-making is a complex task which involves risk comprehension and rational thinking but also various heuristics and external factors. While research has shown that individual traits and situational factors can impact performance with visualizations, they have not been …

A Coarse-Grained Molecular Dynamics Study Of Gas Hydrate Formation And Dissociation, Meisam Adibifard

LSU Doctoral Dissertations

The study of gas hydrates has increased significantly over the last two decades because of their potential application in energy storage, production and transportation, water desalination, refrigeration, gas separation, etc. There is a significant interest in commercially developing natural gas hydrates because the energy content of methane hydrate reservoirs (MHRs) is at least twice that of all conventional fossil fuels combined. Additionally, due to the higher storage capacity of hydrates, it is proposed to sequester CO₂ in the form of CO₂ hydrate, thereby reducing the amount of greenhouse gases. Hence, hydrates offer a dual solution to two of …

Investigation Of Heavy Metal Composition And Associated Health Risks From Selected Groundwater Wells In Temeke, Dar-Es-Salaam, Justin M. Jeremiah

Tanzania Journal of Engineering and Technology (TJET)

Water quality continues to be the challenge to residents in Dar es Salaam due to various anthropogenic activities in the city. This study was conducted to assess groundwater quality by determining concentrations of heavy metals. Both probability and Nonprobability sampling techniques were used to collect samples from 40 groundwater wells in 24 wards of Temeke municipal and analysed using Microwave Plasma Atomic Emission Spectrometer (Agilent 4210 MP-AES) at the Geochemistry Laboratory of the University of Dar es Salaam. Results indicated varying heavy metal concentrations ranging from 0.71 ± 0.08 to 6.64 ± 0.21 mg/l for As, 0.02 ± 0.01 to …

Analysis Of The Factors Affecting The Oil Recovery From Oilseeds In A Multistage Crosscurrent Leaching Process, Samuel V. Manyele

Tanzania Journal of Engineering and Technology (TJET)

The analysis of the total oil recovery from oilseeds in a multi-stage crosscurrent leaching process is presented. The model created using mass balance equations for three stages was used to analyze the factors affecting total oil recovery, To. The key performance factors (raw meal feed flow rate, solvent feed flow rate in each stage, solvent distribution factor for each stage, percent oil in the raw meal (Poil), solids to solution ratio in the underflow (N), solvent to solids ratio (SSR), solvent to oil ratio (SOR) and wash ratio (WR) were varied while assessing To. While SSRi and SORi ranged from …

Development And Testing Of Small-Scale Flash Dryer For Maize Bran, Eden Ngowi

Tanzania Journal of Engineering and Technology (TJET)

Sun drying is the most common technique used to dry various food products due to its economic convenience. However, it is not effective owing to its unreliable nature leading to microbial deterioration and aflatoxin contamination of food. In Tanzania, about 1.3 million tonnes of maize bran are at risk of deterioration annually due to improper drying. The aim of this study was to design, fabricate and test an efficient small-scale flash dryer for maize bran. Using principles of material and energy balance, a small-scale flash dryer with a throughput of 500 kg of dry product per hour was designed resulting …

Guiding 3d Chiral Self-Assembly At Nano/Micro Length Scales Via 3d Printing, Mohsen Esmaeili

Theses and Dissertations

This thesis delves into the intricate realm of 3D printing bio-inspired materials with tailored nano/microscale architectures. The first chapter investigates the flow-induced alignment of cellulose nanocrystals (CNC) during 3D printing, employing a microfluidic strategy integrated with polarized optical microscopy (POM). Birefringence measurements under varying conditions reveal the influence of initial CNC suspension structures on flow-induced patterns, particularly in the chiral nematic phase. Hydrodynamic simulations complement experimental findings, elucidating the impact on CNC particle alignment, providing insights for designing 3D printed architectures with internal chirality for advanced applications.

The second chapter explores the 3D printing of complex geometries inspired by Bouligand …

Mathematical Modeling And Reconstruction Of Porous Media To Understand Transport Phenomena For Electrochemical System Applications, Mitchell Sepe

Theses and Dissertations

Alternative power generation has grown significantly in the space of energy production over the last ten years. Development of new technologies to produce energy is vital to the growing need for electricity. Batteries, solar panels, wind turbines, and countless other renewable energy options have been deemed necessary to create an overall greener future. Fuels cells when combined with electrolyzer show a promising system for stationary power generation. Both technologies are comprised of multiple parts in contact that must work together simultaneously to create an ideal environment for catalytic reactions to take place. A crucial component to a properly functioning cell …

Development Of Dip-Coated Carbon Fibers For Structural Power Composites And Optimization Of Bus Plates For Passively Propagation Resistant Batteries, David Petrushenko

Theses and Dissertations

Increasing demand for lithium-ion batteries in electric vehicles, portable electronics, and electric aircraft is a driving force for the expansion in new battery architectures to achieve higher gravimetric and volumetric efficiencies. In practice, maximizing energy density can be achieved by introducing state-of-the-art materials to increase the capacity of cells or by reducing the system's mass by incorporating lightweight structural materials. An alternative approach is to develop systems capable of performing multiple functions simultaneously that combine mono-functions of the battery and vehicular structure in a multifunctional component capable of storing electrical energy and providing structural support.

The initial focus of this …

Engineering Electronic Properties Of Random Alloys For Catalytic Applications, Andrew N. Okafor

LSU Doctoral Dissertations

Engineering catalytic materials is a key endeavor in the catalysis science to improve the catalytic activity of existing catalysts for specific applications and reduce the dependence on rare metals and minerals. While alloying, or mixing of metals, has been extensively studied, the focus has conventionally been placed on intermetallic phases or nanostructures such as core-shell particles, which are conceptually described by simple lattice models. This research focuses on understanding the catalytic properties of structurally ordered but compositionally disordered (or random) alloys, which have remained under-explored due to complexity at the atomic scale. Existing research focuses on synthesizing multicomponent alloys and …

A Study Of Direct Sensitivity Method Solving Optimal Control Problems With Single And Multiple Time Grids With An Application In An Experimental Hybrid System, Hainan Wang

Theses and Dissertations

Computational methods for optimal control are important for dealing with bottlenecks in industries. By implementing optimal operation strategies obtained from the computational methods into dynamic systems, objectives such as saving energy, reducing cost, exploiting potential, and improving efficiency can be achieved. Computational methods for optimal control have been used in a broad range of disciplines, including aeronautics and astronautics, oil and chemical engineering, power systems, clean energy, biomedical engineering, economics, and management. Due to the great application value of optimal control, its computational methods have drawn worldwide attention. Direct methods are most effective in computational methods for optimal control. Direct …

On The Use Of Cfd Modeling And Analytic Methods To Describe Pressure Drop In Highly Dense Structured Adsorbents In Gas Separation Processes And Fundamentals Of Adsorption, Ryan Timothy Sanders

Theses and Dissertations

The scope of this work can be divided into two main thrusts on topics found within adsorption. The first, and primary, topic is the use of CFD and analytical modeling to describe the flow of gas through a parallel, structured adsorbent channel which is described in Chapters 1 and 2. Chapter 1 establishes a non-experimental methodology based on using a 3D Navier-Stokes (NS) computational fluid dynamics (CFD) model in lieu of experiments, for developing 1D axial pressure drop correlations for structured adsorbents with parallel channels. Chapter 2 utilizes the methodology established in Chapter 1 in order to develop a new …

A Click Chemistry Amplified Nanopore Assay For High Performance Testing Of Protein Biomarkers In Diseases, Xiaoqin Wang

Theses and Dissertations

Nanopore detection technology enables nanometer-scale single-molecule detection, yielding valuable insights into analyte molecules' properties such as size, shape, charge, and concentration. Due to its label-free nature, high sensitivity, and real-time capabilities, it finds widespread application in genomics, proteomics, drug discovery, and environmental monitoring. Click chemistry, encompassing the attachment of a probe or substrate to a biomolecule, termed bioconjugation, features the copper-catalyzed azide-alkyne cycloaddition as a quintessential reaction, forming a 5-membered heteroatom ring. This study harnesses this reaction to craft single-strand DNA probes for nanopore testing, leveraging copper's catalytic properties for signal amplification. Host-guest reaction, a noncovalent bond between molecules, specifically …

Cybersecurity, Image-Based Control, And Process Design And Instrumentation Selection, Dominic Messina, Akkarakaran Francis Leonard, Ryan Hightower, Kip Nieman, Renee O'Neill, Paloma Beacham, Katie Tyrrell, Muhammad Adnan, Helen E. Durand

Chemical Engineering and Materials Science Faculty Research Publications

Within an Industry 4.0 framework, a variety of new considerations are of increasing importance, such as securing processes against cyberattacks on the control systems or utilizing advances in image processing for image-based control. These new technologies impact relationships between process design and control. In this work, we discuss some of these potential relationships, beginning with a discussion of side channel attacks and what they suggest about ways of evaluating plant design and instrumentation selection, along with controller and security schemes, particularly as more data is collected and there is a move toward an industrial Internet of Things. Next, we highlight …

Coal Wettability: A Holistic Overview Of The Data Sets, Influencing Factors, And Knowledge Gaps, Muhammad Arif, Faisal Ur Rahman Awan, Haiyang Zhang, Mirhasan Hosseini

Research outputs 2022 to 2026

Coal seams are naturally occurring geological media offering tremendous potential for gas storage. The wetting characteristics of coals at typical geological formations underpin a diverse array of processes spanning coal resource recovery, combustion, enhanced coal beneficiation, enhanced methane recovery, and CO2 storage for sustainable energy transition. An accurate characterization of coal wettability is thus crucial and remains an active area of research. The intrinsic heterogeneity of coal surfaces and the presence of multicomponent systems add layers of intricacy to wetting behavior. In particular, coal wettability characterization is challenging because it is a complex and multifaceted function of a range of …