Benchmarking Of A Sco2 Heat Exchanger Flow Loop,
2024
Embry-Riddle Aeronautical University
Benchmarking Of A Sco2 Heat Exchanger Flow Loop, David Velasco
Doctoral Dissertations and Master's Theses
Heat transfer of supercritical carbon dioxide (sCO2) was studied experimentally by commissioning a sCO2 flow loop featuring a horizontal tube-in-tube counterflow heat exchanger with a circular cross section. The main objective was to establish experimental heat transfer research capabilities for sCO2 at Embry-Riddle Aeronautical University’s (ERAU) Thermal Science Lab. sCO2 experiences a drastic change in thermophysical properties near its critical point that results in unique heat transfer characteristics. The high pressures at which sCO2 exists make the large gradients in thermophysical and transport properties difficult to study, experimentally and numerically. However, understanding the heat transfer characteristics and thermophysical behavior of …
Quasi-Static And Impact Load Response Of Bfrp-Reinforced Concrete Beams And Post-Terrorist-Attack Sub-Assemblages,
2024
Old Dominion University
Quasi-Static And Impact Load Response Of Bfrp-Reinforced Concrete Beams And Post-Terrorist-Attack Sub-Assemblages, José Luis Carrasquillo
Civil & Environmental Engineering Theses & Dissertations
This dissertation presents the outcome of a theoretical and experimental study of Basalt Fiber Reinforced Polymer (BFRP) reinforced concrete beams and post-terrorist-attack subassemblages subjected to either quasi-static or impact load. Both BFRP reinforcement as well as BFRP fabric are used in this investigation. The sub-assemblage consists of an otherwise two-span beam converted to a fixed-end single-span one owing to the loss of a middle column blasted off during the terrorist attack. The simply supported beams are subjected to a midspan quasistatic or an impact load. However, each sub-assemblage is subjected to a quasi-static load up to collapse to simulate the …
Thermo-Elasto-Plastic Stability Of Biaxially Loaded Hollow Rectangular Section Steel Beam-Columns With Applied Torsion,
2024
Old Dominion University
Thermo-Elasto-Plastic Stability Of Biaxially Loaded Hollow Rectangular Section Steel Beam-Columns With Applied Torsion, George Adomako Kumi
Civil & Environmental Engineering Theses & Dissertations
Presented herein is an experimental and theoretical study of biaxially loaded hollow rectangular section steel beam-columns with applied torsion at elevated temperatures. The theoretical analysis is based on a system of simultaneous materially nonlinear differential equations of equilibrium for which an iterative semi-analytic solution approach is formulated. Although the primary goal of this research is to study the influence of elevated temperatures on the steel member with the complex loading, rigorous analysis is also conducted of the member at ambient temperature for comparison. The experimental part of the study involves conducting tests on the members at both ambient and high …
Shorting At Long Duration: Impact Of Extended Discharge Capacity On Battery Solid Electrolytes,
2024
University of Kentucky
Shorting At Long Duration: Impact Of Extended Discharge Capacity On Battery Solid Electrolytes, Ryan C. Hill, Amanda S. Peretti, Leo J. Small, Erik D. Spoerke, Yang-Tse Cheng
Chemical and Materials Engineering Faculty Publications
Long-duration energy storage (LDES) is critical to a stable, resilient, and decarbonized electric grid. While batteries are emerging as important LDES devices, extended, high-power discharges necessary for cost-competitive LDES present new materials challenges. Focusing on a new generation of low-temperature molten sodium batteries, we explore here unique phenomena related to long-duration discharge through a well-known solid electrolyte, NaSICON. Specifically, molten sodium symmetric cells at 110 ° C were cycled at 0.1 A cm−2 for 1–23 h discharges. Longer discharges led to unstable overpotentials, reduced resistances, and decreased electrolyte strength, caused by massive sodium penetration not observed in shorter duration discharges. …
Seismicity Characteristics Of The Gulf Of Aqaba Seismogenic Zone And Their Hazard Implications In Northwestern Saudi Arabia,
2024
Missouri University of Science and Technology
Seismicity Characteristics Of The Gulf Of Aqaba Seismogenic Zone And Their Hazard Implications In Northwestern Saudi Arabia, Ali Abdelfattah, Mohamed Ezzelarab, Hazem Badreldin, Hassan Alzahrani, Saleh Qaysi, Bassam Abuamarah, Neil Lennart Anderson
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The seismogenic characteristics of the Gulf of Aqaba zone have been assessed using the maximum likelihood method to estimate various earthquake recurrence parameters. These parameters encompass the β-value, annual recurrence rate (λ), and maximum probable magnitude (Mmax). This assessment has identified three sub-seismogenic zones, each corresponding to specific structural faults within the Gulf. These zones are associated with the Aragonese, Arnona and Aqaba faults, delineating pull-apart basin structures in the Gulf of Aqaba. An updated earthquake catalogue has been compiled using a unified moment magnitude (Mw) scale to improve the analysis, established by developing two empirical relationships. According to the …
Valorization Of The Polymeric Constituents In Plastic Wastes Through Thermo-Chemical Processes By Using Viable Metal Oxides Additives,
2024
United Arab Emirates University
Valorization Of The Polymeric Constituents In Plastic Wastes Through Thermo-Chemical Processes By Using Viable Metal Oxides Additives, Labeeb Hamad Ali
Dissertations
The rapid accumulation of different types of plastic waste necessitates the development of effective and economically viable waste management operations. Such a process should ideally not only mitigate associated environmental burdens but also recycle and recover value-added products. Through incineration or pyrolysis, thermal processing has emerged as a mainstream approach to waste management of the ever-increasing loads of different categorized plastic wastes. Throughout the work of the thesis, we have utilized a multitude of complementary techniques spanning material characterizations, catalysis, kinetic modelling, and density functional theory (DFT) to comprehend the complex chemistry that underpins catalytic chemical recycling of plastic wastes. …
Formate Dehydrogenase Immobilized On Metal Organic Framework For Enhanced Conversion Of Co2 To Formate,
2024
United Arab Emirates University
Formate Dehydrogenase Immobilized On Metal Organic Framework For Enhanced Conversion Of Co2 To Formate, Shadeera Rouf
Dissertations
Enzymatic hydrogenation of carbon dioxide (CO2) to formate by formate dehydrogenase (FDH) is a promising technology for reducing CO2 concentrations in an environmentally friendly manner. For practical and economical implementation of the process, however, enhanced reusability of the enzyme is essential, which requires easy separation from the reaction mixture, coupled with sustained stability. One way to achieve this is by using the enzyme in an immobilized form. In this work, the effectiveness of using different metal organic frameworks (MOFs) as promising alternative supports for FDH immobilization has been assessed. A highly stable zirconium-based MOF, UiO66 and its …
Enzymatic Production Of Cyclodextrin Using Cyclodextrin Glycosyltransferase Immobilized In Metal Organic Frameworks (Mofs),
2024
United Arab Emirates University
Enzymatic Production Of Cyclodextrin Using Cyclodextrin Glycosyltransferase Immobilized In Metal Organic Frameworks (Mofs), Babatunde Azeez Ogunbadejo
Dissertations
Cyclodextrins (CDs) and their derivatives have attracted significant attention in the pharmaceutical, food, and textile industries, which has led to an increased demand for their production. CDs are typically produced by the action of cyclodextrin glycosyltransferase (CGTase) on starch. Owing to the relatively high cost of enzymes, the economic feasibility of the entire process strongly depends on the effective retention and recycling of CGTase in the reaction system, while maintaining the enzyme’s activity and stability. Previous supports used for this purpose such as silica and hydrogels, have numerous drawbacks, including enzyme leaching, activity loss and significant mass transfer limitations. The …
Cfd Study On Two-Phase Flow Patterns In A Pipe With 90º Elbow In Different Operating Conditions,
2024
Faculty of Engineering, Tanta University
Cfd Study On Two-Phase Flow Patterns In A Pipe With 90º Elbow In Different Operating Conditions, Hagar Alm-Eldin Bastawissi, Mohammed Ahmed Khafagy, E. A. El Shenawy Prof. Dr., Ahmed M. Salem Dr
Journal of Engineering Research
Recently, CFD has offered a technological solution for modelling multi-phase flow in which we can make endless simulations with reduced expenses and effort in high accuracy results; we shall also mention that experimental studies have limitations for safety considerations when experimenting with flow in high temperature or pressure values or medium nature as in nuclear or chemical flows.In this paper, we used the ANSYS FLUENT CFD program to simulate the two-phase flow in a pipe to study the effect of attaching a 90-degree elbow fitting to the piping system, seeking to find out the change in the pattern and resulting …
Encapsulation And Release Of Calcein From Herceptin-Conjugated Eliposomes,
2024
American University of Sharjah
Encapsulation And Release Of Calcein From Herceptin-Conjugated Eliposomes, Mah Noor Zafar, William G. Pitt, Ghaleb A. Husseini
Faculty Publications
Achieving an optimal therapeutic level is crucial in effectively eradicating cancer cells during treatment. However, conventional chemotherapy-associated systemic administration of anticancer agents leads to many side effects. To achieve the desired control over the target site, active targeting of HER2-positive breast cancer cells can be achieved by conjugating liposomal vesicles with Human Epidermal growth factor Receptor 2 (HER2) and inducing release of the encapsulated drug using ultrasound. To further enhance the delivery efficiency, nanoemulsion droplets exhibiting responsiveness to low-frequency ultrasound are encapsulated within these lipid vesicles. In this study, we prepared four different liposomal formulations, namely pegylated liposomes …
Recent Advances In Solar Photo(Electro)Catalytic Nitrogen Fixation,
2024
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China
Recent Advances In Solar Photo(Electro)Catalytic Nitrogen Fixation, Jun-Bo Ma, Sheng Lin, Zhiqun Lin, Lan Sun, Chang-Jian Lin
Journal of Electrochemistry
Ammonia (NH3) is an essential chemical in modern society. It is currently produced in industry by the Haber-Bosch process using H2 and N2 as reactants in the presence of iron-based catalysts at high-temperature (400–600 oC) and extremely highpressure (20–40 MPa) conditions. However, its efficiency is limited to 10% to 15%. At the same time, a large amount of energy is consumed, and CO2 emission is inevitably. The development of a sustainable, clean, and environmentally friendly energy system represents a key strategy to address energy crisis and environmental pollution, ultimately aiming to achieve carbon neutrality. …
Integrated Process Modeling, Techno-Economic Analysis And Life Cycle Assessment For Enhanced Biogas-To-Energy Sustainability And Efficiency,
2024
University of South Florida
Integrated Process Modeling, Techno-Economic Analysis And Life Cycle Assessment For Enhanced Biogas-To-Energy Sustainability And Efficiency, Rarosue Jennifer Amaraibi
USF Tampa Graduate Theses and Dissertations
This dissertation aims to enhance the cost competitiveness and minimize the environmental footprint of technologies that convert biogas to energy, contributing to global climate change mitigation efforts. Biogas, a by-product of the anaerobic decomposition of organic waste from various sources, is a renewable energy source with the potential to reduce carbon emissions and meet local energy needs. However, widespread adoption requires the development of economically viable and environmentally friendly technologies.The central hypothesis of this dissertation suggests that by adopting a holistic strategy that combines cutting-edge techniques to purify biogas and improve its conversion into valuable liquid fuels, we can substantially …
Understanding Effective Elastic Properties And Stress-Strain Evolution In Composite Granular Rocks Using Discrete Element Modeling,
2024
University of North Dakota
Understanding Effective Elastic Properties And Stress-Strain Evolution In Composite Granular Rocks Using Discrete Element Modeling, Prasad Pothana, Fernando E. Garcia, Kegang Ling
Petroleum Engineering Posters and Presentations
The mechanical behavior of composite granular rocks is a multifaceted phenomenon relevant to various geoengineering applications. Traditional homogenization models and continuum mechanics-based numerical methods often fall short of accurately capturing the intricacies of granular materials. Granular materials exhibit heterogeneity and arching mechanisms governing the force networks that ensure system stability. Unlike continuum-based approaches, particulate discrete element methods have an advantage in assessing effective material properties by considering material heterogeneity and grain-level physical interactions. This study evaluates effective elastic properties using particle flow code using flat-joint contact law for composite binary mixtures with a stiff inclusion embedded within a matrix material. …
Investigation Of Gas Dynamics In Water And Oil-Based Muds Using Das, Dts, And Dss Measurements,
2024
Louisiana State University at Baton Rouge
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 …
Modeling Studies Of An Intensified Reforming/Fischer-Tropsch Synthesis Process For Gas To Liquid Conversion,
2024
University of South Florida
Modeling Studies Of An Intensified Reforming/Fischer-Tropsch Synthesis Process For Gas To Liquid Conversion, Brian Gray
USF Tampa Graduate Theses and Dissertations
Despite rigorous study and advancement in fields of green energy, the world's transportation industry remains poised to continue reliance on liquid hydrocarbon fuels. To date, the primary source of diesel and jet fuels is the petroleum industry; however, continuing trends in rising greenhouse gas emissions present a need for study into processes for the production of synthetic hydrocarbon fuels. The most promising technologies to meet this goal are gas-to-liquid (GtL), biomass-to-liquid (BtL) and coal-to-liquid (CtL). The commonality of these technologies is that they utilize a feedstock to produce carbon monoxide and hydrogen gas (syngas) which becomes the building blocks of …
Mitigation Of Potential Risks In Chemical Laboratories: A Focused Review,
2024
Missouri University of Science and Technology
Mitigation Of Potential Risks In Chemical Laboratories: A Focused Review, Hossein Abedsoltan, Mark B. Shiflett
Chemical and Biochemical Engineering Faculty Research & Creative Works
This review paper presents an analysis of safety practices in chemical laboratories. It encompasses a systematic exploration of various facets including risk assessment, hazard mitigation, and the implementation of safety protocols. Emphasis is placed on the critical role of continuous education and training, advocating a proactive safety culture, and adapting to technological advancements. Additionally, the paper underscores the importance of adhering to regulatory standards, promoting exceeding baseline compliance toward establishing best practices in laboratory safety. This comprehensive approach highlights the dynamic, multifaceted nature of laboratory safety, positioning it as a fundamental aspect of scientific research.
Investigation Of Rare Earth Element Binding To A Surface-Bound Affinity Peptide Derived From Ef-Hand Loop I Of Lanmodulin,
2024
Case Western Reserve University
Investigation Of Rare Earth Element Binding To A Surface-Bound Affinity Peptide Derived From Ef-Hand Loop I Of Lanmodulin, Geeta Verma, Jacob D. Hostert, Alex A. Summerville, Christine E. Duval, Julie N. Renner
Faculty Scholarship
Bioinspired strategies have been given extensive attention for the recovery of rare earth elements (REEs) from waste streams because of their high selectivity, regeneration potential, and sustainability as well as low cost. Lanmodulin protein is an emerging biotechnology that is highly selective for REE binding. Mimicking lanmodulin with shorter peptides is advantageous because they are simpler and potentially easier to manipulate and optimize. Lanmodulin-derived peptides have been found to bind REEs, but their properties have not been explored when immobilized on solid substrates, which is required for many advanced separation technologies. Here, two peptides, LanM1 and scrambled LanM1, are designed …
Engineering Nanofibers: Laboratory Characterization, Microstructural Analysis, And Image Processing Insights,
2024
University of Nebraska at Omaha
Engineering Nanofibers: Laboratory Characterization, Microstructural Analysis, And Image Processing Insights, Sayed Ahmadreza Razian, Mohammad Arjomandi, Kaspars Maleckis
UNO Student Research and Creative Activity Fair
Polymer nanofibers have attracted high interest in a wide array of applications, including biomaterial scaffolding, textiles, sensors, reinforcement in composites, and filtration systems. Many of these applications combine nanofibers into non-woven fabrics for better properties and easier manipulation. The properties and performance of nanofiber-based fabrics are affected by various microstructure parameters, including fiber alignment, diameter, and gap sizes between the nanofibers. These structural parameters can be controlled by adjusting various process parameters during manufacturing process, but the exact process parameter-microstructure relationships vary depending on the polymer system and need to be studied individually. The goal of this study is to …
Aphid-Ant Relationships: The Role Of Cuticular Hydrocarbons
And Different Chemical Stimuli In Triggeringmutualistic Behavior,
2024
Humboldt-Universität zu Berlin, University of Agriculture and Life Sciences, Desert Research Center
Aphid-Ant Relationships: The Role Of Cuticular Hydrocarbons And Different Chemical Stimuli In Triggeringmutualistic Behavior, Amged El-Harairy, Ahmed El-Harairy, Alaa Mahfouz
Department of Chemical and Biomolecular Engineering: Faculty Publications
In ant-aphid interactions, various aphid species offer honeydew to the ant partner and increase their density by ant attendance, whilst others never attend ant species, in which case ants tend to treat them as prey. In this regard, ants should have the ability to distinguish myrmecophile aphid species from non-mutualistic species, so that mutualistic aphids will be accepted as partners rather than prey. Although ant-aphid interactions are now the focus of chemical ecology studies, the role of the different chemical stimuli in determining mutualistic interactions has not been completely clarified. Therefore, we have investigated the cuticular hydrocarbon profile of four …
BUE
Exploring The Morphological Surface Resistance And Optical Absorption Of Thin Black Carbon Nanotube Films For Electronic And Optoelectronic Devices, Ziad Khalifa, Sameh Osama Abdellatif
Chemical Engineering
This study investigates the optical and electrical properties of thin black films of carbon nanotubes (CNTs) fabricated under various conditions to explore their potential integration as either a perfect broadband absorber or enhanced counter electrode. The study involves SEM measurements, surface resistance measurements, and UV–Vis. spectrometer analysis. The results show that the CNT thin films exhibit high electrical conductivity and strong light absorption across various wavelengths. Optically, we investigated the impact of varying the growth temperature and catalyst temperature on the absorption profile of the thin films. The fabricated and deposited CNTs showed broadband absorption spectra, reaching 92.8% of the …
