Chemical Engineering Commons^™

Carboxen Micropreconcentrator Performance For Analyzing Btex In Air., Raymond Daniel Spargo

Electronic Theses and Dissertations

Volatile Organic Compounds (VOCs) are a class of toxic chemicals in environmental air associated with several serious health risks. Some of the most common and concerning VOCs are Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX). To maintain healthy air quality in these environments, researchers pursue instruments and processes to quickly and accurately predict sub-ppb concentrations of BTEX in indoor and outdoor air. By employing a micropreconcentrator (μPC) to combine Solid-Phase Micro-Extraction (SPME) with Gas Chromatography Mass Spectrometry (GC-MS) analysis, trace BTEX content in air samples can be captured, extracted and analyzed. In this thesis, a dual-compartment μPC with Carboxen 1000 …

Comparing Gas Composition From Fast Pyrolysis Of Live Foliage Measured In Bench-Scale And Fire-Scale Experiments, David R. Weise, Thomas H. Fletcher, Timothy J. Johnson, Wei Min Hao, Mark Dietenberger, Marko Princevac, Bret W. Butler, Sara S. Mcallister, Joseph J. O'Brien, E Louise Loudermilk, Roger D. Ottmar, Andrew T. Hudak, Akira Kato, Babak Shotorban, Shankar Mahalingham, Tanya L. Myers, Javier Palarea-Albaladejo, Stephen P. Baker

Faculty Publications

Background. Fire models have used pyrolysis data from oxidising and non-oxidising environments for flaming combustion. In wildland fires pyrolysis, flaming and smouldering combustion typically occur in an oxidising environment (the atmosphere). Aims. Using compositional data analysis methods, determine if the composition of pyrolysis gases measured in non-oxidising and ambient (oxidising) atmospheric conditions were similar. Methods. Permanent gases and tars were measured in a fuel-rich (non-oxidising) environment in a flat flame burner (FFB). Permanent and light hydrocarbon gases were measured for the same fuels heated by a fire flame in ambient atmospheric conditions (oxidising environment). Log-ratio balances of the measured gases …

Genetically-Encoded Optical Barcodes For Single-Cell Analysis, Daniel Pritko

All Theses

Cell barcodes are capable of being used to answer many different biological questions. They have been used to track the lineage of cells to identifying the function of a gene. While there are multiple different methods to creating cell barcodes, they are limited in their scalability and application. In a previous publication we propose and computationally prove an optical single-cell barcoding method that bridges fast and scalable readouts with the benefits of genetic encoding. In this approach fluorescent proteins (fps) are combined to form fluorescent barcodes that can then be analyzed using a spectral flow cytometer. Here, we test the …

Extraction Of Neutron-Gamma Irradiated Diffusion Pump Oils, Cooper L. Tillman

All Theses

This work successfully demonstrates solvent extraction methods for separation of oil from the by-products when two commercially available vacuum pump oils were exposed to an intense neutron and gamma-ray radiation environment. Nuclear fusion power at a commercial scale has accelerated the need for radiation resistant vacuum technology, such as oil-based diffusion pumps. Polyphenyl ether and aromatic silicone oils were irradiated at the Rhode Island Nuclear Science Center (RINSC) up to MGy absorbed doses with neutron and gamma-ray radiation. Solvent extractions were performed using hexane and isopropanol to characterize the oil extraction as a function of total absorbed dose. The by-products …

Modeling Rate Dependent Volume Change In Porous Electrodes In Lithium-Ion Batteries, Taylor R. Garrick, Miguel A. Fernandez, Brian J. Koch, Erin Efimoff, Matthew Jones, Rafid Mollah, Hunter Teel, Xiaoniu Du, Sirivatch Shimpalee, Song-Yul Choe, Venkat R. Subramanian, Jason B. Siegel

Faculty Publications

Automotive manufacturers are working to improve individual cell, module, and overall pack design by increasing the performance, range, and durability, while reducing cost. One key piece to consider during the design process is the active material volume change, its linkage to the particle, electrode, and cell level volume changes, and the interplay with structural components in the rechargeable energy storage system. As the time from initial design to manufacture of electric vehicles decreases, design work needs to move to the virtual domain; therefore, a need for coupled electrochemical-mechanical models that take into account the active material volume change and the …

Mixed Potential Sensor For Natural Gas Leak Detection Design, Manufacturing, And Simulation, Sleight Halley

Chemical and Biological Engineering ETDs

There is a need for a low-cost robust sensor accurately detecting leaks from oil and gas infrastructure. This work presents the development of an electrochemical sensor based on an yttria stabilized zirconia (YSZ) electrolyte with La_0.87Sr_0.13CrO₃, Indium Tin Oxide (In₂O₃ 90 wt%, SnO₂ 10 wt%), Au, Pt electrodes. Selectivity to target gasses of the three sensing electrodes in conjunction with machine learning allows for the accurate discrimination between possible methane sources as well as the quantification of methane concentration. Sensor sensitivity is improved through a low-ionic conductivity substrate of magnesia …

Advances In Electrocatalytic Dehydrogenation Of Ethylamine To Acetonitrile, Yanlin Zhu, Dezhen Wu, Jinyao Tang, Dakota Braaten, Bin Liu, Zhenmeng Peng

Faculty Publications

The electrocatalytic dehydrogenation of ethylamine (EDH), owing to its high hydrogen content, holds broad prospects in electrochemical hydrogen (H2) production, H2 storage, and addressing energy issues, thus deserving wide attention. In this feature article, we first summarized the fundamentals of thermocatalytic and electrocatalytic EDH and reviewed the recent state-of-the-art advances in catalyst research, specifically platinum group metal (PGM) catalysts and non-PGM catalysts. We systematically discussed the potential applications of electrocatalytic EDH in energy storage and conversion. Finally, we provide our perspective on the key challenges and future developments in this field. We believe this feature article will offer helpful guidance …

Opening And Constructing Stable Lithium-Ion Channels Within Polymer Electrolytes, Yangmingyue Zhao, Libo Li, Da Zhou, Yue Ma, Yonghong Zhang, Hang Yang, Shubo Fan, Hao Tong, Suo Li, Wenhua Qu

School of Integrative Biological & Chemical Sciences Faculty Publications

Lithium-ion batteries play an integral role in various aspects of daily life, yet there is a pressing need to enhance their safety and cycling stability. In this study, we have successfully developed a highly secure and flexible solid-state polymer electrolyte (SPE) through the in-situ polymerization of allyl acetoacetate (AAA) monomers. This SPE constructed an efficient Li+ transport channel inside and effectively improved the solid-solid interface contact of solid-state batteries to reduce interfacial impedance. Furthermore, it exhibited excellent thermal stability, an ionic conductivity of 3.82×10-4 S cm-1 at room temperature (RT), and a Li+ transport number (tLi+) of 0.66. The numerous …

Experimental Study On The Effect Of Micro Concentrations Of Hybrid Nanofluids Through Microchannel Heat Sinks, Mohamed Salaheldin Elsherbiny, Moustafa Ali, Moatsem Shahin, Mahmoud El-Kady

Renewable Mechanical Energy

The current study examines the convective heat transfer coefficient experimentally. It assesses the performance of Al2O3, CuO, ZnO, and Ag/ distilled water nanofluids up to a tetra level of hybridization utilized in microprocessor cooling systems equipped with MCHS. An equal ratio of 50%, 33.3%, and 25% for di-, tri-, and tetra-nanofluids, respectively, with a focus on micro-volume fraction 0.025% and comparing it with 0.05%. Operating conditions were as follows: heat loading from 136.4 up to 196.4 watts; and flow rate from 0.35 up to 0.5 LPM. The findings showed that all types of mono nanofluids showed an increase in Nu …

Series Reports From Professor Wei’S Group Of Chongqing University: Advancements In Electrochemical Energy Conversions (1/4): Report 1: High-Performance Oxygen Reduction Catalysts For Fuel Cells, Fa-Dong Chen, Zhuo-Yang Xie, Meng-Ting Li, Si-Guo Chen, Wei Ding, Li Li, Jing Li, Zi-Dong Wei

Journal of Electrochemistry

Two major challenges, high cost and short lifespan, have been hindering the commercialization process of low-temperature fuel cells. Professor Wei’s group has been focusing on decreasing cathode Pt loadings without losses of activity and durability, and their research advances in this area over the past three decades are briefly reviewed herein. Regarding the Pt-based catalysts and the low Pt usage, they have firstly tried to clarify the degradation mechanism of Pt/C catalysts, and then demonstrated that the activity and stability could be improved by three strategies: regulating the nanostructures of the active sites, enhancing the effects of support materials, and …

Kai Wu, The Editorial Board Member Of Journal Of Electrochemistry And Chief Scientist Of Catl, Receives The National Science And Technology Progress Award, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Sorbitol-Electrolyte-Additive Based Reversible Zinc Electrochemistry, Qiong Sun, Hai-Hui Du, Tian-Jiang Sun, Dian-Tao Li, Min Cheng, Jing Liang, Hai-Xia Li, Zhan-Liang Tao

Journal of Electrochemistry

The unstable zinc (Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries. Herein, the hydroxy-rich sorbitol was used as an additive to reshape the solvation structure and modulate the interface chemistry. The strong interactions among sorbitol and both water molecules and Zn electrode can reduce the free water activity, optimize the solvation shell of water and Zn²⁺ ions, and regulate the formation of local water (H₂O)-poor environment on the surface of Zn electrode, which effectively inhibit the decomposition of water molecules, and thus, achieve the thermodynamically stable …

First Announcement Of 76th Annual Meeting Of The International Society Of Electrochemistry, International Society Of Electrochemistry (Ise)

Journal of Electrochemistry

No abstract provided.

Professor Yong Yang, The Editorial Board Member Of Journal Of Electrochemistry, Is Elected As A Fellow Of The Electrochemical Society, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Operational Energy Solutions For A 21st Century Battlefield, Nestor R. Levin

Space and Defense

Development of alternative energy storage and distribution capacity for the modern battlefield is a major national security interest.

Effect Of Local Chain Stiffness On Oligomer Crystallization From A Melt, Pierre Kawak, Christopher Akiki, Douglas R. Tree

Faculty Publications

While the process by which a polymer crystal nucleates from the melt has been extensively studied via molecular simulation, differences in polymer models and simulated crystallization conditions have led to seemingly contradictory results. We make steps to resolve this controversy by computing low-temperature phase diagrams of oligomer melts using Wang-Landau Monte Carlo simulations. Two qualitatively different crystallization mechanisms are possible depending on the local bending stiffness potential. Polymers with a discrete bending potential crystallize via a single-step mechanism, whereas polymers with a continuous bending potential can crystallize via a two-step mechanism that includes an intermediate nematic phase. Other model differences …

Effect Of Flow Velocity On Clogging Induced By Coal Fines In Saturated Proppant Packs: A Transition From Surface Deposition To Bridging, Fansheng Huang, Fengbin Wang, Shuxun Sang, Shiqi Liu, Zhenjiang You

Research outputs 2022 to 2026

Hydraulic fracturing is a widely used technique to enhance the production of coalbed methane reservoirs. However, a common issue is the invasion of coal fines into proppant packs, leading to pore clogging and reduced conductivity. This study investigated the impact of flow velocity on clogging by coal fines in saturated proppant packs to optimize the flow velocity and alleviate clogging during dewatering. Clogging experiments induced by coal fines were conducted on saturated proppant packs with varying superficial velocities. Throughout each experiment, the permeability and effluent concentration were monitored, and the process of clogging was visually observed using an optical microscope. …

Soft Electronics And Systems For Display And Healthcare Applications, Junyi Zhao

McKelvey School of Engineering Graduate Student Theses & Dissertations

Soft electronics are emerging as a revolutionary platform, signifying a pivotal shift from performance-centric priorities to human-centered principles that emphasize accessibility, sustainability, and user experience. As conventional electronics technology approaches its performance ceiling, further improvements in performance metrics have slowed, prompting consumers to place greater importance on user experience and eco-friendliness. Compared to traditional rigid electronics, soft electronics offer the potential to seamlessly integrate biological systems with soft electronic frameworks. Motivated by these demands, this dissertation has been dedicated to bridging fundamental material studies, advanced manufacturing, novel electronic devices, system-level integrations, and practical applications. This interdisciplinary endeavor aims to establish …

Activity: Students Find Conceptual Errors In Ai Output, Janie Brennan

Generative AI Teaching Activities

Instructor asks ChatGPT questions related to a key concept to find one where ChatGPT has conceptual errors. Ask students to find the errors and explain them.

Exploring Co2-Eor Miscibility Flooding Potential For Horus Oil Field, Western Desert, Egypt: A Simulation-Based Investigation, Attia Attia, Adel Salem Prof., Rehab El-Maghraby, Mohamed Youssef Prof.

Petroleum Engineering and Gas

Carbon dioxide (CO2) miscible flooding is becoming increasingly vital in enhanced oil recovery (EOR) not only for residual oil extraction but also for holding a potential for environmental protection, given its association with global warming. This paper explores the impact of EOR using miscible continuous gas injection on enhancing the oil productivity of the aging Horus oil field in Egypt's Western Desert. Horus field faces declining production rates and a significant water cut, with only eight wells out of 24 wells actively producing. Currently, the field maintains a stabilized oil production plateau of 1050 barrels per day, accompanied by a …

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, …

The Role Of Furan Moieties On The Thermal Decomposition And Char Formation Of Intrinsically Fire-Resistant Epoxy Thermosets For Composites, Amy E. Honnig Bassett

Theses and Dissertations

Fire-retardant chemicals added to epoxy thermosets used as coatings, adhesives, and fiber-reinforced polymer composites (FRPCs) negatively impact performance and the environment. This dissertation takes a novel approach to mitigate the flammability of these systems by designing intrinsically fire-resistant epoxies via the incorporation of furan moieties. Glycidyl amines based on furfuryl amine and judiciously selected derivatives of furfuryl amine were synthesized to produce furan-based di-epoxies (FDEs) that were cured by anionic polymerization and with amine curing agents. The furan ring was found to impart additional reactivity for cross-linking and to induce char-forming reactions at higher temperatures. More importantly, the placement of …

Ready, Set, Grow: From Micelles To Giant Vesicles Via Biocatalytic Activation, Nicholas P. Bair, Qinyu Zhu, Bryon A. Staynings, Douglas R. Tree, Walter F. Paxton

Faculty Publications

Controlling physicochemical processes that drive changes in supramolecular aggregates is an important objective toward creating artificial soft micro- and nanomachines. Previous research explored the morphology control of membrane-based materials subjected to externally imposed chemical stimuli. Here, we modulate the microscale morphology of pH-responsive assemblies by using biocatalysis to internally generate changes in global pH. Catalytic reactions offer flexibility in the mechanism and rate at which stimuli are introduced to responsive assemblies, ultimately enabling precision and control over size and morphology. We observed, by dynamic light scattering and fluorescence microscopy, substantial microscale differences between assemblies subjected to manually titrated pH changes …

Biocompatibility Of Mussel-Inspired Water-Soluble Tissue Adhesives, Aishwarya V. Menon, Amelia A. Putnam-Neep, Caitlin E. Brown, Christa J. Crain, Gert Breur, Sanjeev K. Narayanan, Jonathan Wilker, Julie C. Liu

School of Chemical Engineering Faculty Publications

Wound closure in surgeries is traditionally achieved using invasive methods such as sutures and staples. Adhesion-based wound closure methods such as tissue adhesives, sealants, and hemostats are slowly replacing these methods due to their ease of application. Although several chemistries have been developed and used commercially for wound closure, there is still a need for better tissue adhesives from the point of view of toxicity, wet-adhesion strength, and long-term bonding. Catechol chemistry has shown great promise in developing wet-set adhesives that meet these criteria. Herein, we have studied the biocompatibility of a catechol-based copolymer adhesive, poly([dopamine methacrylamide]-co-[methyl methacrylate]-co-[poly(ethylene glycol) methyl …

Development And Characterization Of Automated Screen Mesh-Based Microfluidic Device To Perform Continuous Countercurrent Liquid-Liquid Extraction, Quinn Mcculloch

Nanoscience and Microsystems ETDs

Continuous Countercurrent Microfluidic Liquid-Liquid Extraction (CC-MLLE) shows tremendous potential to generate large numbers of equilibrium stages of separation in a small footprint, with a minimum of pumping, valving, and phase separation steps. However, CC-MLLE rarely appears in literature because it requires a delicate balance between capillary and hydrodynamic forces for deterministic flow.

This dissertation showcases a patented screen mesh-based CC-MLLE invention that performs stable, long-duration (> 36 hr.), countercurrent liquid-liquid extraction and achieves 37 equilibrium stages within a 38.5 μl internal volume. The device is fabricated from chemically resistant polyetheretherketone plastic, using standard machine shop equipment, a plotting cutter, screen …

Performance And Environmental Assessment Of Biochar-Based Membranes Synthesized From Traditional And Eco-Friendly Solvents, Abelline Katusiime Fionah, Isaac Oluk, Laura Brady, Diana M. Byrne, Isabel Escobar

UK CARES Faculty Publications

Water contamination resulting from coal spills is one of the largest environmental problems affecting communities in the Appalachia Region of the United States. This coal slurry contains potentially toxic substances, such as hydrocarbons, heavy metals, and coal cleaning chemicals, and its leakage into water bodies (lakes, rivers, and aquifers) can lead to adverse health effects not only for freshwater bodies and plant life but also for humans. This study focused on two major experiments. The first experiment involved the use of biochar to create a biochar–polysulfone (BC-PSf) flat-sheet multifunctional membrane to remove organic contaminants, and the other major experiment compared …

Investigation Of Ethane Dehydrogenation And Hydrogenolysis On Pt(111), Pt(211) And Pt(100): Bayesian Quantification And Correction Of Dft-Based Enthalpic And Entropic Uncertainties, Mubarak Bello

Theses and Dissertations

Computational investigations of heterogeneously catalyzed reactions using density functional theory (DFT) are often inaccurate, largely due to uncertainties in the choice of DFT functional (enthalpic uncertainty) and approximations for modeling adsorbate movement along the catalyst surface (entropic uncertainty). This work illustrates that both uncertainties are significant in the investigation of the ethane dehydrogenation (EDH) and hydrogenolysis on Pt catalysts by considering the complete deconstruction of ethane on Pt(111), Pt(211), and Pt(100) using microkinetic modeling (MKM). Hence, this work uses both non-calibrated and Bayesian calibrated MKMs to quantify and correct inaccuracies in macroscopic properties due to both uncertainties. A Bayesian approach …

An Experimental Study On Mixed Hydrocarbon Gas On Transport Through Subsurface And Atmospheric Interfaces With Application To Natural Gas Pipline Leak Dection And Quantification, Richard Kolodziej

Civil and Environmental Engineering Theses and Dissertations

Natural gas (NG) production and usage as a fuel source have surged in recent years, becoming a critical component of the global energy system and requiring extensive belowground pipeline infrastructure. Leaks in belowground pipelines release fugitive methane (CH₄) emissions, posing significant environmental, safety, and economic risks. Effective leak detection and quantification (LDAQ) methods are essential for identifying and measuring leaks to enable timely repairs and accurately address these threats. However, few studies have characterized the effectiveness of current and advanced LDAQ survey methods for belowground NG pipelines, with existing work often limited to technology-centric evaluations or studies of …

Pulsing-Induced Healing Of A Surface Crack Of A Nickel-Based Alloy, Liwei Wang, Mingming Quan, Zhen Tan, Ming Liu, Dianlong Wang, Xiao Yang, Ying Liu, Yaning Mao, Zhimin Liang, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

In this work, we demonstrate the feasibility of applying electric pulses to heal surface cracks on nickel-based alloy GH4169 under compressive load. There exists an incubation time for the onset of the healing of a crack, which is associated with local temperature at the crack tip. The crack size decreases with increasing the pulsing time at a constant healing rate prior to complete healing of the crack. Increasing compressive load accelerates the healing process. The electric pulsing leads to the formation of an influential zone surrounding the crack with the finest grain sizes in the healed crack and the coarsest …

Rock Structural Changes Monitored By Fibre Bragg Grating Sensors And Nuclear Magnetic Resonance During Static And Dynamic Carbonated Brine Core Flooding Experiments, Bruno Da Silva Falcão, Lionel Esteban, Ausama Giwelli, Ahmed Al-Yaseri, Alireza Keshavarz, Jeremie Dautriat, Stephanie Vialle, Stefan Iglauer

Research outputs 2022 to 2026

One proposed solution to reduce greenhouse gas emissions is the capture and storage of carbon dioxide (CCS) in geological formations such as depleted oil and gas reservoirs. Injected carbon dioxide (CO2) forms carbonic acid once dissolved in the formation water, which can lead to dissolution of certain types of rock minerals. This may weaken rock geomechanical properties that can jeopardize the safety of long-term storage. In this work, the use of Fibre Bragg Grating (FBG) sensors associated with Nuclear Magnetic Resonance (NMR) was investigated to measure the change in rock strain during core flooding experiments. Optical fibres were glued onto …