University of Nebraska-Lincoln
Old Dominion University
University of Louisville
Michigan Technological University
University of Massachusetts Amherst
Linfield University
University of Arkansas, Fayetteville
Technological University Dublin
Efficient Sintering Of Lunar Soil Using Concentrated Sunlight,
2023
University of Maine
Efficient Sintering Of Lunar Soil Using Concentrated Sunlight, Diprajit Biswas
Electronic Theses and Dissertations
Construction material is one crucial need for long-term habitation on the moon. When concentrated for high heat flux, solar radiation can heat lunar soil or regolith until it sinters at temperatures above 900°C. The solid, sintered soil simulant can be used as construction material. This work explores the conditions leading to effective lunar soil sintering for both direct and indirect irradiated sintering. Lunar soil simulants were sintered using concentrated light from a xenon-arc lamp with varying heat flux intensity. During direct sintering of LHS-1, a sintering range of 860°C-1140°C corresponding to a peak heat flux of 105-120 kW/m2 was identified …
The Influence Of Heat And Mass Transfer On The Setting Rate Of Adhesives Between Porous Substrates,
2023
The University of Maine
The Influence Of Heat And Mass Transfer On The Setting Rate Of Adhesives Between Porous Substrates, Mubarak Mohammed Khlewee
Electronic Theses and Dissertations
The dynamic penetration of fluid into a porous media where other changes are occurring such as temperature or concentration is of interest to a number of situations. However, little experimental and theoretical analysis of this situation is found in the literature where most of the previously published works have studied the penetration with constant physical properties, where there is no change of the fluid as it enters the pores. This situation is important in the setting of adhesives in porous medium such as in the setting of hot melt and water-based adhesives in the production of paper based packaging. The …
Heat Transfer From Plates,
2023
University of Arkansas, Fayetteville
Heat Transfer From Plates, Leanza Trevino
Chemical Engineering Undergraduate Honors Theses
The purpose of this honors thesis is to create an experiment for the CHEG Lab I course. This is a continuation of work done by Alexa Moreno. She created an experiment to model free convection of a horizontal plate. In this report, free and forced convection of a vertical and horizontal plate, respectively are modeled. This report explains the motivation for creating this heat convection experiment, the results of performing the experiment, and provides recommendations for future work on this experiment. Lab handouts are included in the Appendix.
Bridging The Gap Between Phase Behavior And Processing For Renewable And Refinable Carbonaceous Precursors,
2023
Clemson University
Bridging The Gap Between Phase Behavior And Processing For Renewable And Refinable Carbonaceous Precursors, Graham Tindall
All Dissertations
As a category of materials, engineered carbons, specifically carbon fibers, are first-in-class for properties such as modulus, specific strength, and thermal resilience; however, the inability to directly process atomic carbon necessitates the development and optimization of carbonaceous precursors. Because the structure and properties of carbon are highly dependent on the precursors and requisite processing, numerous materials have been investigated as feedstocks for large-scale production. Although cellulose and rayon were among the first investigated, polyacrylonitrile (PAN) is the current hegemon of carbon fiber precursors. PAN feeds 90% of this market, but it is neither inexpensive nor renewable. Because a significant fraction …
Probing The Structure Of Water On Surfaces: From Water Absorption To Ice Nucleation,
2023
Clemson University
Probing The Structure Of Water On Surfaces: From Water Absorption To Ice Nucleation, Jiarun Zhou
All Dissertations
Water, essential for all life forms, is the most abundant, simple, yet mysterious molecule in the world. This molecule, consisting of only three atoms, behaves in unexpectedly different ways with the change of environment. In the past, studies of water under different conditions (temperature, pressure, on the surfaces, with confinement) have been conducted using experimental and computational methods. However, the influence of a given environment on water properties is yet to be fully understood. This dissertation studies water at complex interfaces (surfaces with various chemistry and physics properties) in both the liquid and crystalline states. Various heterogeneous systems used to …
Molecular Understanding Of Zwitterions And Quantum Computing For Sustainability,
2023
University of Kentucky
Molecular Understanding Of Zwitterions And Quantum Computing For Sustainability, Manh Tien Nguyen
Theses and Dissertations--Chemical and Materials Engineering
The sustainable development of society needs sustainable energy solutions and the mitigation of greenhouse gas emissions. One key subject in this area is the development of safe and efficient ion-based batteries. Moreover, CO2 capture is a crucial pathway in mitigating emissions from the combustion of fossil fuels. Ongoing efforts are to improve both technologies' safety and efficiency. This thesis presents our efforts to conduct computational research on understanding advanced zwitterionic electrolytes and CO2 capture. Chapters 2-4 illustrate the computational research to understand ionic solvation in zwitterionic electrolytes. Solid-state electrolytes are essential for safer batteries. While solid polymer electrolytes …
Teflon Replacement In Pans,
2023
The University of Akron
Teflon Replacement In Pans, Teodora Neamtu
Williams Honors College, Honors Research Projects
The purpose of the project is to determine an optimal prepping method of common cooking oils for pans that will be as effective as Teflon non-stick pans. The reason for this is to replace Teflon coating in pans, which can be very toxic for humans and the environment. Teflon has been a common coating for non-stick surfaces that is useful when cooking things such as eggs. To determine an optimal cooking method, three different oils were used: olive oil, vegetable oil, and shortening. The oils were tested on an aluminum pan by cooking egg whites at various temperatures, cooking times, …
Diseño Conceptual De La Recuperación De Galactooligosacáridos (Gos) De Hidrolizados Enzimáticos Por Adsorción Con Carbón Activado,
2023
Universidad de La Salle, Bogotá
Diseño Conceptual De La Recuperación De Galactooligosacáridos (Gos) De Hidrolizados Enzimáticos Por Adsorción Con Carbón Activado, Juan Sebastián Delgado Burgos, Julián Felipe Duque Romero
Ingeniería de Alimentos
Los galactooligosacáridos (GOS) son un tipo de oligosacáridos prebióticos compuestos por unidades de galactosa y glucosa, que tienen propiedades benéficas para la salud intestinal y usualmente son utilizados en la formulación de alimentos funcionales. Estos compuestos se obtienen por medio de la transgalactosilación de lactosa presente en el lactosuero (un subproducto de la industria láctea que representa una problemática ambiental) que resulta en una mezcla de GOS con otros carbohidratos residuales que reducen su pureza, sus propiedades funcionales y su valor económico. En la actualidad, la separación de GOS mediante procesos de adsorción con carbón activado es uno de los …
Impact Of Spallation And Internal Radiation On Fibrous Ablative Materials,
2023
University of Kentucky, Lexington
Impact Of Spallation And Internal Radiation On Fibrous Ablative Materials, Raghava Sai Chaitanya Davuluri
Theses and Dissertations--Mechanical Engineering
Space vehicles are equipped with Thermal Protection Systems (TPS) that encounter high heat rates and protect the payload while entering a planetary atmosphere. For most missions that interest NASA, ablative materials are used as TPS. These materials undergo several mass and energy transfer mechanisms to absorb intense heat. The size and construction of the TPS are based on the composition of the planetary atmosphere and the impact of various ablative mechanisms on the flow field and the material. Therefore, it is essential to quantify the rates of different ablative phenomena to model TPS accurately. In this work, the impact of …
Fugacity-Based Lattice Boltzmann Method For Multicomponent Multiphase Systems,
2023
Old Dominion University
Fugacity-Based Lattice Boltzmann Method For Multicomponent Multiphase Systems, Muzammil Soomro, Luis F. Ayala, Cheng Peng, Orlando M. Ayala
Engineering Technology Faculty Publications
The free-energy model can extend the lattice Boltzmann method to multiphase systems. However, there is a lack of models capable of simulating multicomponent multiphase fluids with partial miscibility. In addition, existing models cannot be generalized to honor thermodynamic information provided by any multicomponent equation of state of choice. In this paper, we introduce a free-energy lattice Boltzmann model where the forcing term is determined by the fugacity of the species, the thermodynamic property that connects species partial pressure to chemical potential calculations. By doing so, we are able to carry out multicomponent multiphase simulations of partially miscible fluids and generalize …
Combustion Characteristics Of Methane, Ethane, Propane, And Butane Blends Under Conditions Relevant Of A Dual-Fuel Diesel And Natural Gas Engine,
2023
West Virginia University
Combustion Characteristics Of Methane, Ethane, Propane, And Butane Blends Under Conditions Relevant Of A Dual-Fuel Diesel And Natural Gas Engine, Christopher Joseph Ulishney
Graduate Theses, Dissertations, and Problem Reports
As natural gas production infrastructure is already in place in most of the world and will continue expanding for the foreseeable future, natural gas is an alternative to traditional liquid petroleum fuels in heavy-duty engines. Dedicated natural gas or dual-fuel diesel-natural gas heavy-duty engines are alternatives to diesel-only power generation equipment. One challenge is the large variation in the natural gas composition available for such applications, which is known to significantly affect engine’s combustion characteristics and the emissions composition. As the literature on dual-fuel combustion under low load engine operating conditions that use more realistic natural gas mixtures (i.e., mixtures …
Outstanding Advantages, Current Drawbacks, And Significant Recent Developments In Mechanochemistry: A Perspective View,
2023
Old Dominion University
Outstanding Advantages, Current Drawbacks, And Significant Recent Developments In Mechanochemistry: A Perspective View, Silvina Pagola
Chemistry & Biochemistry Faculty Publications
Although known since antiquity, mechanochemistry has remained dormant for centuries. Nowadays, mechanochemistry is a flourishing research field at the simultaneous stages of gathering data and (often astonishing) observations, and scientific argumentation toward their analysis, for which the combination of interdisciplinary expertise is necessary. Mechanochemistry’s implementation as a synthetic method is constantly increasing, although it remains far from being fully exploited, or understood on the basis of fundamental principles. This review starts by describing many remarkable advantages of mechanochemical reactions, simplifying and “greening” chemistry in solutions. This description is followed by an overview of the current main weaknesses to be addressed …
More On The Demons Of Thermodynamics,
2023
University of San Diego
More On The Demons Of Thermodynamics, Daniel P. Sheehan, Garret Moddel, James W. Lee
Chemistry & Biochemistry Faculty Publications
No abstract provided.
Operation And Preliminary Energy Balance Of A Portable Kelp Dryer In Maine,
2022
University of Maine
Operation And Preliminary Energy Balance Of A Portable Kelp Dryer In Maine, Tuqa Al-Asadi
Electronic Theses and Dissertations
Seaweed (macroalgae) is a marine resource that has a high economic value. Seaweeds are important commodities as raw material for food or additives and as a source of biomass. One popular species of seaweed is Sugar kelp (Saccharina latissima) – a brown algae that is native to the Maine coast and also a commonly farmed species. It is a rich source of fibers, vitamins, minerals, and antioxidants. Seaweeds are highly perishable due to their high moisture content and will spoil quickly if not preserved, therefore a common practice is to dry the product to prolong storage life and to minimize …
Elucidation Of Active Site And Mechanism Of Metal Catalysts Supported In Nu-1000,
2022
Clemson University
Elucidation Of Active Site And Mechanism Of Metal Catalysts Supported In Nu-1000, Hafeera Shabbir
All Dissertations
Advances in extraction of shale oil and gas has increased the production of geographically stranded natural gas (primarily consisting of methane (C1) and ethane (C2)) that is burned on site. A potential utilization strategy for shale gas is to convert it into fuel range hydrocarbons by catalytic dehydrogenation followed by oligomerization by direct efficient catalysts. This work focuses on understanding metal cation catalysts supported on metal-organic framework (MOF) NU-1000 that will actively and selectively do this transformation under mild reaction conditions, while remaining stable to deactivation (via metal agglomeration or sintering). I built computational models validated by experimental methods to …
Generation Of Phase Transitions Boundaries Via Convolutional Neural Networks,
2022
University of Texas at El Paso
Generation Of Phase Transitions Boundaries Via Convolutional Neural Networks, Christopher Alexis Ibarra
Open Access Theses & Dissertations
Accurate mapping of phase transitions boundaries is crucial in accurately modeling the equation of state of materials. The phase transitions can be structural (solid-solid) driven by temperature or pressure or a phase change like melting which defines the solid-liquid melt line. There exist many computational methods for evaluating the phase diagram at a particular point in temperature (T) and pressure (P). Most of these methods involve evaluation of a single (P,T) point at a time. The present work partially automates the search for phase boundaries lines utilizing a machine learning method based on convolutional neural networks and an efficient search …
Frontiers In The Self-Assembly Of Charged Macromolecules,
2022
University of Massachusetts Amherst
Frontiers In The Self-Assembly Of Charged Macromolecules, Khatcher O. Margossian
Doctoral Dissertations
The self-assembly of charged macromolecules forms the basis of all life on earth. From the synthesis and replication of nucleic acids, to the association of DNA to chromatin, to the targeting of RNA to various cellular compartments, to the astonishingly consistent folding of proteins, all life depends on the physics of the organization and dynamics of charged polymers. In this dissertation, I address several of the newest challenges in the assembly of these types of materials. First, I describe the exciting new physics of the complexation between polyzwitterions and polyelectrolytes. These materials open new questions and possibilities within the context …
Detectability Of Wormholes Through Various Methods,
2022
University of North Florida
Detectability Of Wormholes Through Various Methods, Jonathan W. Keathley
PANDION: The Osprey Journal of Research and Ideas
There are three methods that can possibly detect wormholes: Negative Temperature, Hawking/ Phantom Radiation, and Kα iron emission lines. This paper discusses whether or not any of these three methods are useful ways to detect wormholes with today’s technology and if so, which one is the best and which is the worst. As it turns out, all of these methods have their flaws and impracticalities. After looking through all the evidence and comparing it to what capabilities we have currently, there is clearly a best and worst method. The best method to detect possible wormhole candidates is through the detection …
Droplet-Based Two-Phase Thermal Management,
2022
Washington University in St. Louis
Droplet-Based Two-Phase Thermal Management, Junhui Li
McKelvey School of Engineering Theses & Dissertations
The rapid development of electronic systems with ever-higher power densities in a wide range of applications requires new advanced thermal management methods. Droplet-based two-phase thermal management technologies are considered promising solutions to conquer the cooling challenges in the electronic industries. The heat transfer behavior of droplets is based on several important fundamental processes, such as droplet evaporation, droplet impact on heated surfaces, and molten droplet impact. In this dissertation, four research projects are completed to explore the insights of these fundamental processes. For droplet evaporation, I introduce an investigation of diffusion confinement of droplets evaporating on a supported pillar structure. …
Droplet Dynamics And Heat Transfer During Condensation On Lubricant-Infused Surfaces,
2022
Washington University in St. Louis
Droplet Dynamics And Heat Transfer During Condensation On Lubricant-Infused Surfaces, Jianxing Sun
McKelvey School of Engineering Theses & Dissertations
Inspired by pitcher plants, a micro/nano- structured solid surface infused with low-surface-tension lubricant constitutes a novel class of biomimetic surfaces—lubricant-infused surfaces (LISs). Unlike solid hydrophobic and superhydrophobic surfaces, a LIS is “hemi-solid and hemi-liquid”. The thin lubricating film can extraordinarily decrease adhesion and avoid contact line pinning between the working fluid and the underlying solid, displaying many desirable properties, such as excellent liquid repellency, suppression of fouling, and self-healing. Hence, LISs are ideal for applications where liquids or contaminants must be efficiently removed from surfaces in harsh environments. For example, LISs can promote stable dropwise condensation of water or low-surface-tension …
