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A Portable Point-Of-Care Device Using Joule Heating And Latent Energy Storage For The Temperature Regulation Of Isothermal Nucleic Acid Amplification Tests, Aubrey Lynn Schultz 2021 University of Arkansas, Fayetteville

A Portable Point-Of-Care Device Using Joule Heating And Latent Energy Storage For The Temperature Regulation Of Isothermal Nucleic Acid Amplification Tests, Aubrey Lynn Schultz

Graduate Theses and Dissertations

Accurate and early diagnosis of infectious diseases extremely important. Rapid diagnosis allows for effective treatment and increases the chance for recovery without complications. Additionally, the ability to test the populace frequently, swiftly, and affordably significantly aids in containing wide-scale outbreaks. In terms of specificity and sensitivity, nucleic acid amplification tests (NAAT) are one of the best options for diagnosing infectious diseases. Isothermal NAATS present a unique opportunity to create diagnostic tests deployed at a Point-of-Care (POC) level. Specifically, loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA) have the potential to deliver reliable POC diagnostics in low-resource settings. When designing …


Thermodynamic Vapor-Liquid Equilibrium In Naphtha-Water Mixtures, Sandra Milena Lopez-Zamora 2021 The University of Western Ontario

Thermodynamic Vapor-Liquid Equilibrium In Naphtha-Water Mixtures, Sandra Milena Lopez-Zamora

Electronic Thesis and Dissertation Repository

Naphtha is used to dilute the froth from bitumen treatment. Naphtha is recovered using a Naphtha Recovery Unit (NRU) and sent back to the froth dilution step. To minimize the environmental and economic impact of the NRU, it is imperative to maximize the naphtha recovery. It is, in this respect, that enhanced NRU Vapour-Liquid-Liquid equilibrium data is a significant value. The prediction of phase equilibria for hydrocarbon/water blends in separators, is a subject of considerable importance for chemical processes. Despite its relevance, there are still pending questions. Among them, is the prediction of the correct number of phases. While a …


Economic Feasibility Of Mixed Plastic Waste Pyrolysis Using Twin Reactor System In Northwest Arkansas, Carol Rogers, Patricia Means, Renato Gonzalez, Kaida Sheets, Hayden Townsend 2021 University of Arkansas, Fayetteville

Economic Feasibility Of Mixed Plastic Waste Pyrolysis Using Twin Reactor System In Northwest Arkansas, Carol Rogers, Patricia Means, Renato Gonzalez, Kaida Sheets, Hayden Townsend

Chemical Engineering Undergraduate Honors Theses

Plastic waste generation is increasing at an unsustainable rate while recycling solutions remain stagnant. As a chemical means of recycling, mixed plastic waste pyrolysis can generate synthetic oil appropriate for use as fuel in power generation from plastic waste that otherwise accumulates in landfills. With the scaling of a commercial plastic pyrolysis process in Northwest Arkansas (NWA) modeled after an operational sawdust pyrolysis unit in Huntsville, Arkansas, economic analysis resulted in 26.3% internal rate of return. Therefore, construction of a commercial mixed plastic-to-fuel pyrolysis plant is economically justified and should be pursued. To effectively implement the proposed design, NWA must …


Predicting Henry's Law Constants Of Volatile Organic Compounds Present In Bourbon Using Molecular Simulations., Christopher A Abney 2021 University of Louisville

Predicting Henry's Law Constants Of Volatile Organic Compounds Present In Bourbon Using Molecular Simulations., Christopher A Abney

Electronic Theses and Dissertations

Henry’s Law describes the partitioning of molecules into liquid and gas phases at low concentrations. Henry’s Law, which is based upon a species-dependent constant and the gas phase partial pressure, is useful for predicting phase behavior of dilute solutes. However, Henry’s Law constants are difficult to measure experimentally or to predict using structure-property or thermodynamic models. Herein, molecular simulations were used to calculate Henry’s Law constants for 18 volatile organic compounds (VOCs) present in bourbon. The novel simulations analyzed solvation thermodynamics of small organic molecules in 120 proof ethanol. A fast-growth non-equilibrium free energy method was used in which the …


Graphical Design And Analysis Of Mass Exchange Networks Using Composition Driving Forces, Nessren Mohamed Farrag, Dina Ahmed Kamel, Ayat Ossama Ghallab, Mamdouh Ayad Gadalla, Mai Kamal Fouad 2021 The British University in Egypt

Graphical Design And Analysis Of Mass Exchange Networks Using Composition Driving Forces, Nessren Mohamed Farrag, Dina Ahmed Kamel, Ayat Ossama Ghallab, Mamdouh Ayad Gadalla, Mai Kamal Fouad

Chemical Engineering

Pinch analysis is a methodology for minimizing energy and mass consumption in different industries. It has been widely applied for more efficient processes. This study presents a new graphical-approach to analyze and design Mass Integration (MI) and exchange networks that follows Pinch principles to guarantee maximum mass recovery with minimum losses. This technique uses the composition driving forces in network representation as it rules the mass transfer between streams. The proposed approach can be applied on both existing mass networks as well as new ones. This graphical representation a visual descriptive design tool to describe and explain the details of …


Relationship Between Thermal Conductivity And Free Electrons In Metal, Yansong Liu 2021 Linfield University

Relationship Between Thermal Conductivity And Free Electrons In Metal, Yansong Liu

Senior Theses

An experiment was designed and conducted to explore the relationship between thermal conductivity with free electrons in metal. In the experiment, copper, iron, aluminum, and titanium rods with close diameters were used to carry out the experiment. Each rod was heated up by a heat unit at one end while cooled on the other end with a heat sink to maintain a steady state. DC current was applied to rods in the direction along, as well as against, the heat flow. Thermal conductivities were measured in these two situations for each rod. Results showed electrons do dominate thermal flow inside …


Statistics Of Particle Diffusion Subject To Oscillatory Flow In A Porous Bed, Kelly Curran 2021 University of Vermont

Statistics Of Particle Diffusion Subject To Oscillatory Flow In A Porous Bed, Kelly Curran

Graduate College Dissertations and Theses

Enhanced diffusion of a suspended particle in a porous medium has been observed when an oscillatory forcing has been imposed. The mechanism of enhancement, termed oscillatory diffusion, occurs when oscillating particles occasionally become temporarily trapped in the pore spaces of the porous medium, and are then later released back into the oscillatory flow. This thesis investigates the oscillatory diffusion process experimentally, stochastically, and analytically. An experimental apparatus, consisting of a packed bed of spheres subjected to an oscillatory flow field, was used to study the dynamics of a single particle. A variety of statistical measures were used and developed to …


Thermal And Thermophysical Properties Of Anionic Amines And Their Aqueous Solutions For Co2 Capture In Confined Environments, Randi Swanson 2021 University of South Alabama

Thermal And Thermophysical Properties Of Anionic Amines And Their Aqueous Solutions For Co2 Capture In Confined Environments, Randi Swanson

Undergraduate Honors Theses

Air revitalization for the International Space Station (ISS) has been identified by NASA as a mission critical need which requires improvement. The current method uses13X zeolite, a solid adsorbent, to adsorb carbon dioxide. While this is effective, the zeolite adsorbent produces dust that is unwelcome on the space station. Furthermore, the adsorbentis too sensitive to humidity in moderate temperature gas streams [1]. Aqueous solutions of ionic amines show promise as a safe and efficient solution, as they do not volatilize and are not water sensitive [2]. Specifically, anionic amines have the most potential because of the amine functional group’s ability …


Thermal/Structural Analysis Of The Axion Quantum Metrology Cavity And Its Components, Tyler Funk 2021 Northern Illinois University

Thermal/Structural Analysis Of The Axion Quantum Metrology Cavity And Its Components, Tyler Funk

Graduate Research Theses & Dissertations

This research was centered around maximizing the capability to cool dielectric material within a containment unit, or Photonic Band Gap (PBG) cavity, designed for detecting axion dark matter and identifying the unit’s thermal properties. There are multiple types of PBG cavities, but the latest version that axion researchers wish to use has been theorized to contain possible issues related to its thermal properties. Thermal conductivity is an issue with the dielectric material because it is made from alumina which is highly insulative. This is important since the research is being done in a cryogenic environment and the thermal noise affects …


Tailoring Thermoresponsive Poly(N-Isopropylacrylamide) Toward Sensing Perfluoroalkyl Acids, Dustin Thomas Savage 2021 University of Kentucky

Tailoring Thermoresponsive Poly(N-Isopropylacrylamide) Toward Sensing Perfluoroalkyl Acids, Dustin Thomas Savage

Theses and Dissertations--Chemical and Materials Engineering

Widespread distribution of poly- and perfluoroalkyl substances (PFAS) in the environment combined with concerns for their potentially negative health effects has motivated regulators to establish strict standards for their surveillance. The United States Environmental Protection Agency issued a cumulative domestic threshold of 70 ppt for water supplies, and this bar is even lower in some local districts and other countries. Monitoring PFAS consequently requires sensitive analytical equipment to meet regulatory specifications, and liquid chromatography with tandem mass spectroscopy (LC/MS/MS) is the most common technique used to satisfy these requirements. Though extremely sensitive, the instrument is often burdened by pretreatment regimens, …


Investigation Of Iron-Nickel Based Nanoparticles As Catalysts For Oxygen Evolution Reaction (Oer), Prashant Acharya 2021 University of Arkansas, Fayetteville

Investigation Of Iron-Nickel Based Nanoparticles As Catalysts For Oxygen Evolution Reaction (Oer), Prashant Acharya

Graduate Theses and Dissertations

Hydrogen fuel is increasingly seen as an appealing alternative by both the scientific and the industrial communities in the drive towards a clean energy future. Hydrogen, unlike fossil-based fuels, does not release carbon dioxide, a chief component of greenhouse gases, upon combustion. However, more than 95% of the hydrogen in the world is still produced by burning fossil fuels as this method is currently the only economically feasible option at a large industrial scale.

Water electrolysis shows a lot of potential in both hydrogen generation and in the storage of energy from renewable sources such as wind and sunlight. Likewise, …


New Horizons For Processing And Utilizing Red Mud, M. Archambo 2021 Michigan Technological University

New Horizons For Processing And Utilizing Red Mud, M. Archambo

Dissertations, Master's Theses and Master's Reports

Red mud is an industrial slurry waste that is produced as a byproduct of the Bayer process for alumina. The waste is generated in large quantities, up to a ratio of 2:1 against the valued product alumina. Red mud exhibits many chemical and physical properties that categorize it as a hazardous material. Due to the addition of sodium hydroxide in processing, the pH is typically at values close to 13. Small particle size discourages separation from water for disposal, so drying red mud happens over many years.

The pH of red mud can be reduced with inexpensive reagents. Carbon dioxide …


Interactions Of Lignin Dimers With Engineered Surfaces And Model Cell Membranes For Design Of Lignin-Based Materials, Mahsa Moradipour 2021 University of Kentucky

Interactions Of Lignin Dimers With Engineered Surfaces And Model Cell Membranes For Design Of Lignin-Based Materials, Mahsa Moradipour

Theses and Dissertations--Chemical and Materials Engineering

Capitalizing on byproducts of industrial and agricultural economies is among the utmost goals of sustainability. Of particular interest for commercial upgrading is lignin, a phenolic biopolymer found in the cell walls of plants which is the second most abundant biopolymer on Earth after cellulose. Due to its heterogeneous structure, deconstructing lignin to selected small molecules for use as chemicals or advanced materials has been elusive. This work capitalizes on a “bottom up” approach to the synthesis of lignin oligomers of known bond chemistry to better understand their interfacial interactions.

The potential pharmacological mechanism of lignin deconstruction components and their toxicological …


Understanding Absorption, Supersaturation, And Drug Activity In Solution: Working Towards Developing A More Biorelevant Media, Freddy Arce 2021 University of Kentucky

Understanding Absorption, Supersaturation, And Drug Activity In Solution: Working Towards Developing A More Biorelevant Media, Freddy Arce

Theses and Dissertations--Pharmacy

With the looming dominance of poorly water-soluble chemical entities within the pharmaceutical pipeline, the pharmaceutical industry has leaned on the use of supersaturating drug delivery systems (SDDSs) to achieve efficacious concentrations within the gastrointestinal fluids. SDDSs aim to achieve concentrations in solutions greater than the solubility of the lowest energy crystalline form. However, the generation of supersaturated solutions of active pharmaceutical ingredients (APIs) creates a strong crystallization potential, which is undesirable.

In product development, supersaturating products often fail in Phase I and Phase II clinical trials due to poor oral bioavailability and a lack of in vivo efficacy. Pre-clinical testing …


Ultrafast Thermal Modification Of Strong Coupling In An Organic Microcavity, Bin Liu, Vinod M. Menon, Matthew Y. Sfeir 2021 CUNY City College

Ultrafast Thermal Modification Of Strong Coupling In An Organic Microcavity, Bin Liu, Vinod M. Menon, Matthew Y. Sfeir

Publications and Research

There is growing interest in using strongly coupled organic microcavities to tune molecular dynamics, including the electronic and vibrational properties of molecules. However, very little attention has been paid to the utility of cavity polaritons as sensors for out-of-equilibrium phenomena, including thermal excitations. Here, we demonstrate that non-resonant infrared excitation of an organic microcavity system induces a transient response in the visible spectral range near the cavity polariton resonances. We show how these optical responses can be understood in terms of ultrafast heating of electrons in the metal cavity mirror, which modifies the effective refractive index and subsequently the strong …


Testing The Effectiveness Of Various Fabrics For Use In Protective Face Coverings, Isaac Daley 2021 The University of Akron

Testing The Effectiveness Of Various Fabrics For Use In Protective Face Coverings, Isaac Daley

Williams Honors College, Honors Research Projects

Facemask requirements have been heavily implemented as a result of the COVID-19 pandemic. The purpose of this study was to test various fabrics that could be used in face coverings and determine which materials are best for reducing virus transmission rates. Of the seven fabrics tested, five were conventional home-use fabrics and the other two were surfaces modified with hydrophobic organosilanes. Wettability and droplet adherence tests were performed on each material. The materials that performed the best were decyltrichlorosilane (DTS) modified cotton, perfluorotrichlorosilane (FTS) modified cotton, and polyester. Contact angles for water droplets on these fabrics were 106°, 93°, and …


Dynamic Modelling And Control Of Grid-Level Energy Storage Systems, Sai Pushpitha Vudata 2021 West Virginia University

Dynamic Modelling And Control Of Grid-Level Energy Storage Systems, Sai Pushpitha Vudata

Graduate Theses, Dissertations, and Problem Reports

The focus of this work is on two energy storage technologies, namely pumped storage hydroelectricity (PHS) and secondary batteries. Under secondary battery technologies, two potential technologies for grid-scale storage, namely high-temperature sodium-sulfur (NaS) battery and vanadium redox flow battery (VRFB), are investigated. PHS is a largescale (>100 MW) technology that stores and generates energy by transporting water between two reservoirs at different elevations. The goal is to develop a detailed dynamic model of PHS and then design the controllers to follow the desired load trajectory accurately with high efficiency. The NaS battery and VRFB are advanced secondary batteries which …


Reduction Of Copper And Iron Oxide Mixture With Local Reducing Gases, Shokhrukh Khojiev 2020 Tashkent State Technical University named after Islam Karimov

Reduction Of Copper And Iron Oxide Mixture With Local Reducing Gases, Shokhrukh Khojiev

Acta of Turin Polytechnic University in Tashkent

The article analyzes the scientific problems of the copper industry. In particular, the main problem with the classical production of copper is the causes of large amounts of slag and the negative impact of these wastes on the environment. Accordingly, the main component that forms the slag is iron, and the higher its content in the original copper concentrate, the more slag is formed, and at the same time a large amount of copper metal is released into the waste. The departure is indicated by evidence. To prevent this problem, a technology has been proposed to reduce copper sulfide concentrates …


A Computational Investigation Of The Interstitial Oxidation Thermodynamics Of A Mo-Nb-Ta-W High Entropy Alloy Beyond The Dilute Regime, Adib J. Samin 2020 Air Force Institute of Technology

A Computational Investigation Of The Interstitial Oxidation Thermodynamics Of A Mo-Nb-Ta-W High Entropy Alloy Beyond The Dilute Regime, Adib J. Samin

Faculty Publications

High entropy alloys (HEAs) are promising candidates for high-temperature structural material applications. Oxidation is a major factor that must be accounted for when designing such materials and it is thus important to study the oxidation behavior of HEAs to enable the optimum design of next generation materials. In this study, the thermodynamic behavior of interstitial oxygen in a Mo-Nb-Ta-W high entropy alloy was explored beyond the dilute limit. This was accomplished by sampling configurations of the HEA and HEA-oxygen systems from an isothermal–isobaric ensemble using a series of first-principle-based Monte Carlo simulations. It was found that the interstitial oxygen had …


Local Structure And Dynamic Studies Of Mixed Ch4-Co2 Gas Hydrates Via Computational Simulation And Neutron Scattering, Bernadette Rita Cladek 2020 University of Tennessee, Knoxville

Local Structure And Dynamic Studies Of Mixed Ch4-Co2 Gas Hydrates Via Computational Simulation And Neutron Scattering, Bernadette Rita Cladek

Doctoral Dissertations

Permeated throughout the ocean floor and arctic permafrost, natural gas hydrates contain an estimated 3000 trillion cubic meters, over three times that of traditional shale deposits, of CH4 that is accessible for extraction. Gas hydrates are a crystal structure in which water molecules form a cage network, the host, through hydrogen bonds while trapping a guest molecule such as CH4 in the cavities. These compounds form naturally where the appropriate low temperature and high pressure conditions occur. A promising and tested method of methane recovery is through exchange with CO2, which energetically takes place of the …


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