Transport Phenomena Commons^™

Zeolite 13x Particles With Porous Tio2 Coating And Ag2o Nanoparticles As Multi-Functional Filler Materials For Face Masks, Wei Su, Kaiying Wang, Han Yu, Fateme Fayyazbakhsh, Jeremy Watts, Yue-Wern Huang, Jee-Ching Wang, Xinhua Liang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Adsorbent components in face masks are crucial for protecting individuals exposed to dangerous situations. In this study, one porous TiO₂ layer was deposited on zeolite 13X particles by coating hybrid organic/inorganic titanium alkoxide film via molecular layer deposition (MLD), followed by heat treatment to remove organic components in the MLD film. Various concentrations of Ag₂O nanoparticles were impregnated on the TiO₂-coated 13X particles, offering a wide range of antibacterial, antifungal, and antiviral characteristics. The obtained composite particles were characterized using X-ray photoelectron spectroscopy and thermal gravimetric analysis to study the composition and mass loading of …

Fabrication And Performance Of Scalable Bio-Engineered Porous Layers For Efficient Co2 Capture, Mary Sharon Rose Bondugula

Theses and Dissertations

This dissertation addresses the critical challenge of mitigating climate change by advancing CO2 capture technologies. As global CO2 emissions continue to rise, effective methods for capturing and separating CO2 from industrial processes are essential to combat climate change. Existing CO2 capture systems, such as Pressure Swing Adsorption (PSA) and Temperature Swing Adsorption (TSA), often rely on packed bed designs that face limitations, including poor heat and mass transfer, slow gas diffusion, and low thermal conductivity, reducing their efficiency. To overcome these challenges, this dissertation explores innovative solutions by developing advanced adsorbent coatings and scalable bed configurations.

This research begins by …

Collision Dynamics Of Compound Droplets In Microchannels: A Combined Numerical And Data-Driven Study, S M Abdullah Al Mamun

Dissertations

Understanding and predicting the hydrodynamic interactions of micron-scale droplets is crucial in a wide range of industrial and real-life applications, including microfluidics, pharmaceutics, drug delivery, food science, and enhanced oil recovery. These multi-phase and multi-scale phenomena are further complicated by the presence of core droplets of an immiscible fluid within shell droplets, known as compound droplets. The collisions and interactions of droplets in emulsions are influenced by various physical and geometric parameters, leading to distinct rheological and dynamic responses. This research employs numerical methods for a systematic parametric study of both simple and compound droplet pair collisions under confined shear …

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. …

Optoelectronic And Morphological Surface Resistance Evaluation Of Laser-Induced Graphene Counter Electrodes For Potential Applications In Cesium Lead Halide Perovskite Solar Cells, Ziad Khalifa, Sameh Osama Abdellatif, Rami Ghannam

Chemical Engineering

This study investigates the physicochemical, optical, and electrical characterization of laser-induced graphene (LIG) samples for integration as counter electrodes in cesium lead halide perovskite solar cells. The impact of laser processing parameters on electrode performance is explored, including laser power, laser speed, and beam defocus. Density functional theory (DFT) computational modeling is employed for atomistic investigation and work function estimation, demonstrating the density of states (DOS), quantum capacitance of the graphene sheets, and energy work function. NiO is utilized as a hole transport layer, and the energy work function of LIG is tuned accordingly. SEM measurements estimate thin film porosity, …

Model To Demonstrate Effects Of Mass Transfer And Applied Current In An Electrolytic Cell, George Ankrah

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

This study investigates the relationship between applied current and resulting cell potential in an electrolytic system, considering the transport of electroactive species. By applying Michael Faraday's laws of electrolysis and the Nernst-Planck equation, the behavior of electroactive species in diffusion-controlled systems with and without stirring is modeled. The plots demonstrate how stirring enhances ion transport and establishes a stable Nernst diffusion layer, affecting the kinetics of electrochemical reactions. Understanding these dynamics is crucial for optimizing electrolysis processes.

Sulfonated Lignin-Based Ionomer Biocomposite Membranes For Redox Flow Batteries, Aiswarya Mechoor

All Theses

The current benchmark membrane for vanadium redox flow batteries (VRFBs), Nafion™, accounts for up to 40% of the cost of the battery and suffers from poor ion selectivity, leading to diminished battery performance. Consequently, alternative ionomer membranes, such as sulfonated poly(ether ether ketone) (SPEEK), have recently garnered attention due to their lower cost and similar performance properties to Nafion. However, like Nafion, SPEEK also suffers from poor ion selectivity. In this study, we attempt to address the issue of poor ion selectivity by developing SPEEK–lignin composite membranes containing fractionated and functionalized lignin. Specifically, two lignin fractions – a low molecular …

Smart Manufacturing Of Cement: From Lab-Scale Simulation And Testing To Industry-Scale Deployment., Juan David Tabares Tamayo

Electronic Theses and Dissertations

Cement kilns are controlled by experienced process operators who follow experience-based industry guidelines using data collected and fundamental knowledge. The manufacturing process, which is equipped with sensors and equipment, transfers data/information to the operators to aid standardized decision-making operations. In contrast, companies have used such data to develop and implement digital solutions for predictive control systems; in effect, FLSmidth and Rockwell Automation. However, despite the availability of automated control systems and investigation in automation for process monitoring and optimization, opportunities to radically optimize cement manufacturing are still abundant and in need of implementation. Therefore, this research developed simulation models and …

Improving Static Cold Storage Life Of The Human Heart Before Transplant, Juan Sebastian Rodriguez Paez

Theses and Dissertations

Organ storage and transportation are critical steps for the success of organ transplantation. Static cold storage (SCS) of hearts for heart transplantation (HTx) remains the standard approach. However, SCS may involve damage to the tissue resulting from extended hypothermic preservation, potentially affecting organ viability. More over, the temperature distribution on and within the heart is unknown during heart transplantation. Therefore, there is an interest to study different stages of the heart transplantation process towards determining the 3D temperature distribution on and within the heart. There could be a possibility of having a hypothermic injury in different parts of the heart …

Sulfonated Ionomer Composite Membranes For Use In Vanadium Redox Flow Batteries, Xueting Wang

All Dissertations

While vanadium redox flow batteries (VRFBs) have garnered significant attention as a promising scalable energy storage technology, the current membrane material used in this technology, Nafion™, suffers from high cross mixing of vanadium ions in the liquid electrolytes, directly impacting battery performance properties such as the voltage and coulombic efficiencies, as well as resulting in a reduction in the overall battery lifetime. The use of ionomer nancomposites has proven to be one promising route of directly addressing the issue of high ion crossover, though the mechanism by which the nanoparticles act to reduce crossover remains in open question. Herein, the …

Research Of The Influence Of Physical And Chemical Properties Of Coal On The Gasification Process Using The Example Of Angren Brown Coal, Murodjon Mamitbekovich Kavkatbekov, Rakhimzhan Pachekhanovich Babakhodzhaev

Technical science and innovation

The influence of the properties of Angren brown on the process of layered gasification was studied. The dependence of the calorific value of the resulting gas on the quality characteristics of coal when using air as a gasifying agent has been established. Methods are shown for increasing the calorific value of gas obtained during the gasification process when using coal with different moisture content and different fractional composition. The features of technological processes in the reaction zones of a laboratory gas generator have been studied. Based on generally accepted methods, the volume fractions of flammable components, as well as the …

Development Of Dynamic Modeling And Estimation Techniques For Condition Monitoring Of Advanced Energy Systems, Vivek Saini

Graduate Theses, Dissertations, and Problem Reports (ETD)

The integration of renewable energy sources into the electric grid requires the current fleet of fossil-fired power plants to operate more flexibly, leading to frequent load changes that stress critical high temperature boiler components that were primarily designed for base load operations. The more complex operating scenarios can modify component damage, compromising reliability and increasing operational costs. To ensure efficient plant operations, adaptive condition monitoring tools generalizable for different plant configurations are essential for recognizing the impacts of load-following, improving safety, and preventing outages. This dissertation work is primarily focused on the development of advanced modeling and estimation techniques frameworks …

Experimental Evaluation Of Mesh Size In Physically Crosslinked Polymer Gels Using Dynamic Light Scattering, Duncan M. Hill

Honors Theses

Block copolymer gels are under consideration as drug delivery patches. Controlling and modeling the transport inside the gel is an important contribution to the successful delivery of pharmaceuticals. The diffusive transport of a solute – such as a therapeutic compound – within the gel can be described by the mesh size of the gel, which is defined as the distance between polymer chains. Existing experimental evaluations of mesh size do not work for block copolymer gels due to differences in the fundamental gel structure. As such, an experimental method of measuring mesh size of block copolymer gels using dynamic light …

Cellular Level Changes Induced In Cancer Cells Due To Microgravity, Sai Deepika Reddy Yaram

Graduate Theses, Dissertations, and Problem Reports (ETD)

The increase in human activity in space has revealed several kinds of physiological challenges brought on by the absence of Earth's gravitational pull. NASA observed that during spaceflight, astronauts experience a 1-1.5% monthly loss in the mineral density of weight-bearing bones, with rehabilitation efforts on Earth often proving ineffective. This issue extends to muscles, the neuro vestibular system, the cardiovascular system, and vision. Cancer has emerged as a significant cause of mortality among astronauts, with studies up to 2017 showing that 41.3% of natural cause deaths among U.S. astronauts were due to cancer, primarily due to space radiation exposure. Cancer …

Mathematical Modeling Of Coupled Heat And Mass Transfer In Metal-Hydride Hydrogen Storage Systems, Muhammad Hasnain

College of Graduate Studies: Theses & Dissertations

As a promising clean energy carrier hydrogen has recently gained significant interest, but its efficient and safe storage is a major challenge. Compared to the gaseous state and liquid state, metal hydrides (MH) offer a potentially more effective storage approach for hydrogen. However, the main challenge in this approach is the low thermal conductivity of the MH bed that leads to low heat transfer and ultimately to higher charging and discharging times. The purpose of this work is to develop an in-house comprehensive heat and mass transfer model for hydrogen sorption in MH reactors to simulate the dynamic behavior of …

Nanoparticle Stabilized Interfaces And Their Effect On Foam Stability, Nicole T. Donovan

Dissertations and Theses

No abstract provided.

Alkaline Potassium Polyacrylate Electrolytes For Rechargeable Zinc-Manganese Dioxide Batteries, Jungsang Cho

Dissertations and Theses

Zinc (Zn)–manganese dioxide (MnO₂) rechargeable batteries have high specific theoretical capacity as well as being environmentally friendly, intrinsically safe and low-cost. Liquid electrolytes, such as potassium hydroxide (KOH), are historically used in these batteries; however, many failure mechanisms of the Zn–MnO₂ battery chemistry result from the use of liquid electrolytes, including the formation of electrochemically inactive compounds and shape change of Zn electrodes during charge and discharge cycling. This led to incorporation of an alkaline polymer electrolyte as an alternative to the liquid KOH electrolyte in Zn-MnO₂ rechargeable batteries, with the aim of making them non-spillable …

Hydrodynamics Of Drops And Particles Driven By Marangoni And Diffusiophoretic Forces, Subramaniam Chembai Ganesh

Dissertations and Theses

This study investigates the hydrodynamics of particles and drops driven by forces generated by an asymmetrical physical and chemical surrounding environment. In the first part, a novel colloidal motor design driven by surface tension forces is proposed, utilizing an active Janus particle encapsulated in an immiscible liquid drop to form a compound drop/particle. Marangoni forces induced by asymmetric solute adsorption at the liquid-liquid interface of the drop propels the compound system. The propulsion speeds of the motor are analyzed for various relative sizes and configurations of the Janus particle and the encapsulating drop and the effects of varying the transport …

Numerical Modeling Of Thermal Runaway In Lithium-Ion Batteries Using Decomposition Kinetics And Inter-Cell Contact Resistance, Shehzad Khan

College of Graduate Studies: Theses & Dissertations

Lithium-ion batteries (LIBs) are central in numerous high-demand applications due to their high energy density and prolonged cycle life. Despite these advantages, their susceptibility to thermal runaway (TR) poses a significant safety risk, with the potential for catastrophic failures. This study focuses on the thermal behavior of prismatic lithium-ion cells, using a finite volume-based partial differential equation (PDE) solver developed in MATLAB and JULIA to model TR behavior. This solver accurately simulates transient behaviors, convection, diffusion, and source terms across various coordinate systems. By engaging in a series of increasing complex case studies, this research aims to identify the critical …

Sustained Release Systems For Endometrial Cancer, Claire E. Rowlands

Theses and Dissertations--Chemical and Materials Engineering

Endometrial cancer (EC) is the sixth most common cancer in women worldwide and is the most common cancer of female reproductive organs. From 2007-2016 there has been a global rise in incidence of EC of 1.3 %. Typically, EC is treated with surgery, but at later stages surgery is less effective requiring chemotherapy and/or radiation therapy. These treatment options are less effective than surgery and there are very few FDA approved chemotherapies for EC. The minuscule number of effective treatment options as well as an increase in incidence shows the need for creating improved treatments for EC. There has been …

Novel Membrane Materials For Nutrient Recovery From Nutrient-Rich Resources, Km Prottoy Shariar Piash

Graduate Theses, Dissertations, and Problem Reports (ETD)

Global demand for fertilizer production is expanding substantially to meet the food demand of an increasing world population. Anaerobic digestate (AD) of various centralized wastewater facilities contains substantial amounts of ammonium (NH₄⁺) (300-800 mg/L), potassium (K⁺) (13-120 mg/L), and phosphorus (P) (30-100 mg/L)- based nutrients. In addition to reducing energy costs and CO₂ emissions compared to conventional fertilizing raw material manufacturing, recovering nutrients from these waste streams could help mitigate problems such as eutrophication, which otherwise incurs billions of dollars losses to US economy annually. Apart from nutrients, wastewater streams also contain organic pollutants …

Polylactic Acid (Pla) Containing Talc Microparticles And Amorphous Polyhydroxyalkanoates (Aphas) For Improved Barrier And Mechanical Properties In Food Packaging, Mohammed Alfaifi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Polylactic acid (PLA) is a biobased and compostable polymer that is increasingly being used as an alternative to petroleum-based, non-biodegradable polymers for single-use food packaging due to its environmental benefits. It is also commercially available in large quantities, and it can be processed like polyethylene. However, it has a higher water-vapor permeability (WVP) as compared to polyolefins and polyethylene terephthalate that are the incumbent materials. This results in a competitive disadvantage in employing PLA for packaging baked goods since the shelf life of the food is likely to be reduced. In the past, barrier properties of PLA were improved by …

Data-Driven Modeling Of Oxygen Kinetics In La0.6sr0.4co0.2fe0.8o3−Δ (Lscf) For High-Temperature Reduction Of Co2 In An Electrolysis Cell, Ferron Campbell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electrolysis systems are critical to several societal applications, particularly energy storage and conversion. Developing these systems requires a detailed knowledge of the chemistry and thermodynamics of the materials used in the electrolysis cell. This work focuses on using embedded scientific machine learning as an efficient way to build an interpretable model for the reaction and transport kinetics in the LSCF electrode, whose performance directly influences the electrolysis system’s performance. The models developed in this study are trained using the publicly available machine learning package, FoKL-GP. This package incorporates a robust Gibbs sampler that employs a forward variable selection process to …