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Full-Text Articles in Engineering

Adsorptive Properties And On-Demand Magnetic Response Of Lignin@Fe3o4 Nanoparticles At Castor Oil–Water Interfaces, Mohammad J. Hasan, Emily Westphal, Peng Chen, Abishek Saini, I-Wei Chu, Sarah J. Watzman, Esteban E. Ureña-Benavides, Erick S. Vasquez Jan 2023

Adsorptive Properties And On-Demand Magnetic Response Of Lignin@Fe3o4 Nanoparticles At Castor Oil–Water Interfaces, Mohammad J. Hasan, Emily Westphal, Peng Chen, Abishek Saini, I-Wei Chu, Sarah J. Watzman, Esteban E. Ureña-Benavides, Erick S. Vasquez

Chemical and Materials Engineering Faculty Publications

Lignin@Fe3O4 nanoparticles adsorb at oil–water interfaces, form Pickering emulsions, induce on-demand magnetic responses to break emulsions, and can sequester oil from water. Lignin@Fe3O4 nanoparticles were prepared using a pH-induced precipitation method and were fully characterized. These were used to prepare Pickering emulsions with castor oil/Sudan red G dye and water at various oil/water volume ratios and nanoparticle concentrations. The stability and demulsification of the emulsions under different magnetic fields generated with permanent magnets (0–540 mT) were investigated using microscopy images and by visual inspection over time. The results showed that the Pickering emulsions were more stable at the castor oil/water …


Preparation, Cure, And Characterization Of Cyanate Ester-Epoxy Blends Containing Reactive Flame Retardants, Mustafa Mukhtar, Donald A. Klosterman Jan 2023

Preparation, Cure, And Characterization Of Cyanate Ester-Epoxy Blends Containing Reactive Flame Retardants, Mustafa Mukhtar, Donald A. Klosterman

Chemical and Materials Engineering Faculty Publications

Cyanate ester resins are sometimes mixed with lower cost epoxy monomers to modify cost, toughness, and processing capabilities. Despite the high performance of these thermosetting polymers, flame retardancy remains an issue. This study examined blends of three different commercial cyanate ester monomers (LVT-100, LECy, and XU-71787.02) and diglycidyl ether of bisphenol A (DGEBA) at 50/50 wt% of each type. The blends were successfully reacted with two reactive flame retardants (FR): 9,10-dihydro-9-ox-9-phosphaphenanthrene-10-oxide (DOPO) and poly(m-phenylene methylphosphonate) (PMP) at phosphorus contents ranging from 0 to 3 wt%. The curing behavior of EP/CE blends was investigated using differential scanning calorimetry (DSC). It was …


Synthesis Of A Phosphorus-Based Epoxy Reactive Flame Retardant Analog To Diglycidyl Ether Of Bisphenol A (Dgeba) And Its Behavior As A Matrix In A Carbon Fiber Composite, Mustafa Mukhtar Nov 2022

Synthesis Of A Phosphorus-Based Epoxy Reactive Flame Retardant Analog To Diglycidyl Ether Of Bisphenol A (Dgeba) And Its Behavior As A Matrix In A Carbon Fiber Composite, Mustafa Mukhtar

Chemical and Materials Engineering Faculty Publications

This paper describes the synthesis of a phosphorus-based flame retardant that is a chemical analog of diglycidyl ether of bisphenol A (DGEBA), as well as its incorporation as a matrix into carbon fiber laminates. Carbon fiber composites, if used for structural applications in mass transport vehicles (aircraft, trains), will require some aspects of improved fire performance to be used safely in those applications. The first phase of work involved the development of two separate synthesis routes to produce the flame retardant monomer, referred to as Phosphorus-DGEBA or simply P-DGEBA. The second step was to determine the viability of the compound's …


Identification Of Lithocholic Acid As A Molecular Glass Host For Room-Temperature Phosphorescent Materials, John J. Flynn, Zachary M. Marsh, Douglas M. Krein, Steven M. Wolf, Joy E. Haley, Erick S. Vasquez, Thomas M. Cooper, Nicholas P. Godman, Tod A. Grusenmeyer Aug 2022

Identification Of Lithocholic Acid As A Molecular Glass Host For Room-Temperature Phosphorescent Materials, John J. Flynn, Zachary M. Marsh, Douglas M. Krein, Steven M. Wolf, Joy E. Haley, Erick S. Vasquez, Thomas M. Cooper, Nicholas P. Godman, Tod A. Grusenmeyer

Chemical and Materials Engineering Faculty Publications

Lithocholic acid was identified as a molecular glass host material for room temperature phosphorescent (RTP) chromophores. Differential scanning calorimetry (DSC) was performed on a series of structurally similar, biologically sourced molecules, including lithocholic acid, β-estradiol, cholesterol, and β-sitosterol, in an effort to identify new amorphous molecular glasses independent of plasticizing additives. DSC analysis revealed lithocholic acid and β-estradiol form stable molecular glasses post thermal processing unlike neat cholesterol and β-sitosterol. The ability of lithocholic acid and β-estradiol to stabilize high wt. % loadings of d10-pyrene and a mixture of d10-pyrene and an iridium chromophore, bis(2,4-difluorophenylpyridinato)-tetrakis(1-pyrazolyl)borate iridium(III) (FIr6), was also investigated. …


Preparation, Cure, And Characterization Of Cyanate Ester-Epoxy Blends, Donald A. Klosterman May 2022

Preparation, Cure, And Characterization Of Cyanate Ester-Epoxy Blends, Donald A. Klosterman

Chemical and Materials Engineering Faculty Publications

Cyanate ester resins are often blended with lower cost epoxy monomers in order to modify the cost, toughness, and processing characteristics. There are also several choices of catalysts that can be used to improve processing, namely by reducing the cure temperature. This study was undertaken to illustrate how a designed experiment approach can be used to systematically investigate a wide range of material combinations and illuminate the basic cure behavior of some simple cyanate ester – epoxy blend combinations. Two commercial cyanate ester resin products were obtained. Each was blended with a bisphenol F based epoxy resin at two different …


Entrepreneurially Minded Learning In The Unit Operations Laboratory Through Community Engagement In A Blended Teaching Environment, Erick S. Vasquez, Kelly Bohrer, Abraham Noe-Hays, Arthur Davis, Matthew Dewitt, Michael J. Elsass Nov 2021

Entrepreneurially Minded Learning In The Unit Operations Laboratory Through Community Engagement In A Blended Teaching Environment, Erick S. Vasquez, Kelly Bohrer, Abraham Noe-Hays, Arthur Davis, Matthew Dewitt, Michael J. Elsass

Chemical and Materials Engineering Faculty Publications

Online and blended learning opportunities in Chemical Engineering curriculum emerged due to COVID-19. After eight weeks of in-person Unit Operations Laboratory sessions, a remote-learning open-ended final project was assigned to student teams. The assignment involved aspects related to entrepreneurial-minded learning (EML) and community-based learning (CBL). Results show correlations between self-directed learning and the EML framework. Continuous support and involvement of a community partner correlate to students' m


Analytical Model For Electromagnetic Induction In Pulsating Ferrofluid Pipe Flows, Huiyu Wang, John G. Monroe, Swati Kumari, Serhiy O. Leontsev, Erick S. Vasquez, Scott M. Thompson, Matthew J. Berg, Dibbon Keith Walters, Keisha B. Walters Aug 2021

Analytical Model For Electromagnetic Induction In Pulsating Ferrofluid Pipe Flows, Huiyu Wang, John G. Monroe, Swati Kumari, Serhiy O. Leontsev, Erick S. Vasquez, Scott M. Thompson, Matthew J. Berg, Dibbon Keith Walters, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

No abstract provided.


Facile Fabrication And Characterization Of Kraft Lignin@Fe3o4 Nanocomposites Using Ph Driven Precipitation: Effects On Increasing Lignin Content, Frankie A. Petrie, Justin M. Gorham, Robert T. Busch, Serhiy O. Leontsev, Esteban E. Ureña-Benavides, Erick S. Vasquez Jun 2021

Facile Fabrication And Characterization Of Kraft Lignin@Fe3o4 Nanocomposites Using Ph Driven Precipitation: Effects On Increasing Lignin Content, Frankie A. Petrie, Justin M. Gorham, Robert T. Busch, Serhiy O. Leontsev, Esteban E. Ureña-Benavides, Erick S. Vasquez

Chemical and Materials Engineering Faculty Publications

This work offers a facile fabrication method for lignin nanocomposites through the assembly of kraft lignin onto magnetic nanoparticles (Fe3O4) based on pH-driven precipitation, without needing organic solvents or lignin functionalization. Kraft lignin@Fe3O4 multicore nanocomposites fabrication proceeded using a simple, pH-driven precipitation technique. An alkaline solution for kraft lignin (pH 12) was rapidly injected into an aqueous-based Fe3O4 nanoparticle colloidal suspension (pH 7) under constant mixing conditions, allowing the fabrication of lignin magnetic nanocomposites. The effects of increasing lignin to initial Fe3O4 mass content (g/g), increasing in ratio from 1:1 to 20:1, are discussed with a complete chemical, structural, and …


Comparison Of Tensile Properties Of Triaxial Braided Carbon Fiber Composites Made From Vacuum Assisted Resin Transfer Molding (Vartm) And Autoclave Molding, Donald A. Klosterman, Charles Browning May 2021

Comparison Of Tensile Properties Of Triaxial Braided Carbon Fiber Composites Made From Vacuum Assisted Resin Transfer Molding (Vartm) And Autoclave Molding, Donald A. Klosterman, Charles Browning

Chemical and Materials Engineering Faculty Publications

Triaxially braided fiber composites are increasingly being used in aerospace, ballistic, and sporting good applications due to their inherent damage tolerance, torsional stability, and cost compared to woven fabrics and unidirectional preforms. There have been numerous publications over the past 15-20 years on the mechanical properties and failure mechanisms of triaxial braided composites. However, most of these have involved panels made with autoclave curing. In the present study, braided carbon fiber composites were made using autoclave curing and vacuum assisted resin transfer molding (VARTM). The goal of the study was to compare the physical and tensile properties of quasi-isotropic panels …


Detection And Aggregation Of Listeria Monocytogenes Using Polyclonal Antibody Gold-Coated Magnetic Nanoshells Surface-Enhanced Raman Spectroscopy Substrates, Robert T. Busch, Farzia Karim, Yvonne Sun, H. Christopher Fry, Yuzi Liu, Chenglong Zhao, Erick S. Vasquez Apr 2021

Detection And Aggregation Of Listeria Monocytogenes Using Polyclonal Antibody Gold-Coated Magnetic Nanoshells Surface-Enhanced Raman Spectroscopy Substrates, Robert T. Busch, Farzia Karim, Yvonne Sun, H. Christopher Fry, Yuzi Liu, Chenglong Zhao, Erick S. Vasquez

Chemical and Materials Engineering Faculty Publications

Magnetic nanoshells with tailored surface chemistry can enhance bacterial detection and separation technologies. This work demonstrated a simple technique to detect, capture, and aggregate bacteria with the aid of end-functionalized polyclonal antibody gold-coated magnetic nanoshells (pAb-Lis-AuMNs) as surface-enhanced Raman spectroscopy (SERS) probes. Listeria monocytogenes were used as the pathogenic bacteria and the pAb-Lis-AuMNs, 300 nm diameter, were used as probes allowing facile magnetic separation and aggregation. An optimized covalent bioconjugation procedure between the magnetic nanoshells and the polyclonal antibody was performed at pH six via a carbodiimide crosslinking reaction. Spectroscopic and morphological characterization techniques confirmed the fabrication of stable pAb-Lis-AuMNs. …


Fabrication And Characterization Of Electrospun Poly(Acrylonitrile-Co-Methyl Acrylate)/Lignin Nanofibers: Effects Of Lignin Type And Total Polymer Concentration, Suchitha Devadas, Saja M. Nabat Al-Ajrash, Donald A. Klosterman, Kenya A. Crosson, Garry S. Crosson, Erick S. Vasquez Mar 2021

Fabrication And Characterization Of Electrospun Poly(Acrylonitrile-Co-Methyl Acrylate)/Lignin Nanofibers: Effects Of Lignin Type And Total Polymer Concentration, Suchitha Devadas, Saja M. Nabat Al-Ajrash, Donald A. Klosterman, Kenya A. Crosson, Garry S. Crosson, Erick S. Vasquez

Chemical and Materials Engineering Faculty Publications

Lignin macromolecules are potential precursor materials for producing electrospun nanofibers for composite applications. However, little is known about the effect of lignin type and blend ratios with synthetic polymers. This study analyzed blends of poly(acrylonitrile-co-methyl acrylate) (PAN-MA) with two types of commercially available lignin, low sulfonate (LSL) and alkali, kraft lignin (AL), in DMF solvent. The electrospinning and polymer blend solution conditions were optimized to produce thermally stable, smooth lignin-based nanofibers with total polymer content of up to 20 wt % in solution and a 50/50 blend weight ratio. Microscopy studies revealed that AL blends possess good solubility, miscibility, and …


Magnetically Induced Demulsification Of Water And Castor Oil Dispersions Stabilized By Fe3o4-Coated Cellulose Nanocrystals, Mohammad J. Hasan, Frankie A. Petrie, Ashley E. Johnson, Joshua Peltan, Meredith Gannon, Robert T. Busch, Serhiy O. Leontsev, Erick S. Vasquez, Esteban E. Ureña-Benavides Mar 2021

Magnetically Induced Demulsification Of Water And Castor Oil Dispersions Stabilized By Fe3o4-Coated Cellulose Nanocrystals, Mohammad J. Hasan, Frankie A. Petrie, Ashley E. Johnson, Joshua Peltan, Meredith Gannon, Robert T. Busch, Serhiy O. Leontsev, Erick S. Vasquez, Esteban E. Ureña-Benavides

Chemical and Materials Engineering Faculty Publications

Superparamagnetic iron oxide (Fe3O4) nanoparticle (NP) coated cellulose nanocrystals (CNCs) were synthesized and used to prepare emulsions with magnetically controlled stability. Magnetite NPs were deposited onto the surface of wood pulp CNCs (WCNCs) and bacterial CNCs (BCNCs) by a one-step coprecipitation method. The effect of the CNC to Fe3O4 mass ratio (1:1, 1:2, and 1:4) was varied to optimize the colloidal, magnetic and emulsifying properties of the hybrid NPs. TEM images showed that the 1:4 ratios lead to greater coverage of Fe3O4 than lower Fe3O4 loadings (1:1, and 1:2). The CNCs and Fe3O4 appeared to interact via hydrogen bonding between …


Investigation Of Various Techniques For Controlled Void Formation In Fiberglass/Epoxy Composites, Donald A. Klosterman, Charles Browning, Issa Hakim, Kyle Lach Aug 2020

Investigation Of Various Techniques For Controlled Void Formation In Fiberglass/Epoxy Composites, Donald A. Klosterman, Charles Browning, Issa Hakim, Kyle Lach

Chemical and Materials Engineering Faculty Publications

The effect of porosity in composite materials has been studied for years due to its deleterious effects on mechanical properties, especially matrix dominated properties. Currently there is an increasing use of composites in infrastructure worldwide, for example bridge components, residential and building structures, marine structures such as piers and docks, and large industrial chemical tanks. Most of these applications use fiberglass composites. Unfortunately, most of the published literature has focused on carbon fiber composites, in which fiber diameter and gas-fiber interactions are different than fiberglass composites. Therefore, the present study was undertaken to revisit the effect of porosity but specifically …


Impact Of Team Formation Approach On Teamwork Effectiveness And Performance In An Upper-Level Undergraduate Chemical Engineering Laboratory Course, Erick S. Vasquez, Matthew J. Dewitt, Zachary J. West, Michael J. Elsass Feb 2020

Impact Of Team Formation Approach On Teamwork Effectiveness And Performance In An Upper-Level Undergraduate Chemical Engineering Laboratory Course, Erick S. Vasquez, Matthew J. Dewitt, Zachary J. West, Michael J. Elsass

Chemical and Materials Engineering Faculty Publications

This study focuses on the impact of team formation approach on teamwork effectiveness and performance spanning three years of instruction of the chemical engineering unit operations laboratory, which is an upper-level undergraduate laboratory course. Team formation approaches changed each year, and assessment tools, including peer-assessment, academic performance, and course evaluations, were employed to evaluate team performance. Approaches included three cases: instructor-selected teams based on GPA with the objective of a similar cumulative average GPA for each team, student self-selected teams, and a combination of self-selected teams with instructor-selected teams for a final experiment. For the third case, new teams were …


Organophosphorus-Hydrazides As Potential Reactive Flame Retardants For Epoxy, Alexander B. Morgan, Vladimir Benin, Donald A. Klosterman, Abdulhamid Bin Sulayman, Mustafa Mukhtar, Mary L. Galaska Jan 2020

Organophosphorus-Hydrazides As Potential Reactive Flame Retardants For Epoxy, Alexander B. Morgan, Vladimir Benin, Donald A. Klosterman, Abdulhamid Bin Sulayman, Mustafa Mukhtar, Mary L. Galaska

Chemical and Materials Engineering Faculty Publications

For structural composites used in vehicles and aircraft, flame retardant chemistries which enhance char formation and reduce heat release are preferred. Phosphorus-based and phosphorus–nitrogen flame retardants for epoxies have been well studied to date, but phosphorus hydrazides have not been studied for their flame-retardant potential in epoxy. These hydrazides offer some novel structures and they can potentially offer a combination of vapor and condensed phase flame retardant action. A series of eight compounds were systematically investigated in this study as reactive flame retardants in a bisphenol F epoxy/aliphatic amine resin system at a level of 2.5 wt% phosphorus. Results suggest …


Assessing Magnetic Iron Oxide Nanoparticles Properties Under Different Thermal Treatments, Erick S. Vasquez, Evan M. Prehn, Keisha B. Walters Dec 2019

Assessing Magnetic Iron Oxide Nanoparticles Properties Under Different Thermal Treatments, Erick S. Vasquez, Evan M. Prehn, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Magnetic nanoparticle structures have been examined as potential carrier vehicles and substrates in a wide range of applications where they undergo mechanical, chemical and/or thermal manipulation to allow for their modification, conjugation and transport. For safe and effective use, it is imperative to not only measure the initial physicochemical and structural properties of nanomaterials, but also identify and quantify any property changes related to a loss of chemical and/or physical integrity during processing and usage conditions. In this study an assessment of iron oxide magnetic nanoparticle thermal stability using modulated differential scanning calorimetry (mDSC) and a controlled-heating system is conducted …


Optothermal Microbubble Assisted Manufacturing Of Nanogap-Rich Structures For Active Chemical Sensing, Farzia Karim, Erick S. Vasquez, Yvonne Sun, Chenglong Zhao Oct 2019

Optothermal Microbubble Assisted Manufacturing Of Nanogap-Rich Structures For Active Chemical Sensing, Farzia Karim, Erick S. Vasquez, Yvonne Sun, Chenglong Zhao

Chemical and Materials Engineering Faculty Publications

Guiding analytes to the sensing area is an indispensable step in a sensing system. Most of the sensing systems apply a passive sensing method, which waits for the analytes to diffuse towards the sensor. However, passive sensing methods limit the detection of analytes to a picomolar range on micro/nanosensors for a practical time scale. Therefore, active sensing methods need to be used to improve the detection limit in which the analytes are forced to concentrate on the sensors. In this article, we have demonstrated the manufacturing of nanogap-rich structures for active chemical sensing. Nanogap-rich structures are manufactured from metallic nanoparticles …


Optimization And Structural Stability Of Gold Nanoparticle–Antibody Bioconjugates, Robert T. Busch, Farzia Karim, John Weis, Yvonne Sun, Chenglong Zhao Sep 2019

Optimization And Structural Stability Of Gold Nanoparticle–Antibody Bioconjugates, Robert T. Busch, Farzia Karim, John Weis, Yvonne Sun, Chenglong Zhao

Chemical and Materials Engineering Faculty Publications

Gold nanoparticles (AuNPs) bound with biomolecules have emerged as suitable biosensors exploiting unique surface chemistries and optical properties. Many efforts have focused on antibody bioconjugation to AuNPs resulting in a sensitive bioconjugate to detect specific types of bacteria. Unfortunately, bacteria thrive under various harsh environments, and an understanding of bioconjugate stability is needed. Here, we show a method for optimizing Listeria monocytogenes polyclonal antibodies bioconjugation mechanisms to AuNPs via covalent binding at different pH values, from 2 to 11, and 2-(N-morpholino)ethanesulfonic acid (MES), 3-(N-morpholino)propanesulfonic acid, NaOH, HCl conditions. By fitting Lorentz curves to the amide I and II regions, we …


Computational And Experimental Approach To Understanding The Structural Interplay Of Self-Assembled End-Terminated Alkanethiolates On Gold Surfaces, Juganta K. Roy, Erick S. Vasquez, Henry P. Pinto, Swati Kumari, Keisha B. Walters, Jerzy Leszcynski Aug 2019

Computational And Experimental Approach To Understanding The Structural Interplay Of Self-Assembled End-Terminated Alkanethiolates On Gold Surfaces, Juganta K. Roy, Erick S. Vasquez, Henry P. Pinto, Swati Kumari, Keisha B. Walters, Jerzy Leszcynski

Chemical and Materials Engineering Faculty Publications

Applications of self-assembled monolayers (SAMs) on surfaces are prevalent in modern technologies and drives the need for a better understanding of the surface domain architecture of SAMs. To explore structural interaction at the interface between gold surfaces and a hydroxyl-terminated alkanethiol, 11-hydroxy-1-undecanethiol, (C11TH) we have employed a combined computational and experimental approach. Density functional theory (DFT) calculations were carried out on the thiol–gold interface using both the Perdew–Burke–Ernzerhof (PBE) and van der Waals (optB86b) density functionals. Our ab initio molecular dynamics (AIMD) simulations revealed that the interface consists of four different distinguished phases, each with different C11TH orientations. Experiments involved …


Development Of A Methodology For Characterizing Reaction Kinetics, Rheology, And In-Situ Compaction Of Polyimide Prepregs During Cure, James Raymond Magato, Donald A. Klosterman Aug 2019

Development Of A Methodology For Characterizing Reaction Kinetics, Rheology, And In-Situ Compaction Of Polyimide Prepregs During Cure, James Raymond Magato, Donald A. Klosterman

Chemical and Materials Engineering Faculty Publications

PMR-type polyimide prepregs are challenging to fabricate into high quality composites due to volatiles that are generated and must be removed in situ during processing. The current work was conducted to develop accurate, reliable, and practical characterization techniques of the prepreg rheology, volatile generation, and subsequent volatile removal from the prepreg during composite fabrication. Thermal analysis was used to characterize volatile generation, reaction rates, and rheology. A novel approach was used to measure the thickness of the prepreg in situ during vacuum bag/oven processing using a high-temperature LVDT. Experimental results are presented for the commercially available RM-1100 polyimide/carbon prepreg system, …


The Effect Of Fabric Architecture On The Processing And Properties Of Composites Made By Vacuum Assisted Resin Transfer Molding, Francois Ntakobatagize, Oscar Ntakontagize, Donald A. Klosterman May 2019

The Effect Of Fabric Architecture On The Processing And Properties Of Composites Made By Vacuum Assisted Resin Transfer Molding, Francois Ntakobatagize, Oscar Ntakontagize, Donald A. Klosterman

Chemical and Materials Engineering Faculty Publications

The goal of this research project was to evaluate and compare the effect of fabric architecture on the processing and properties of composites made by Vacuum Assisted Resin Transfer Molding (VARTM). The fabric architectures investigated included plain weave, satin weave, and warp-knit unidirectional. The fiber types included E-glass and standard modulus carbon fiber. Flat panels were fabricated with a lab scale VARTM process using an epoxy resin system. Fabric plies were cut to 45 cm x 30 cm (18 in. x 12 in.), and the number of plies used depended on the fiber areal weight of each fabric to produce …


Generation Of Silver Nanoparticle Pharmacokinetic Profiles In A Lung Model, Rachel Galaska Apr 2019

Generation Of Silver Nanoparticle Pharmacokinetic Profiles In A Lung Model, Rachel Galaska

Honors Theses

Nanomaterial technologies are becoming increasingly prevalent in consumer and industrial applications, including drug delivery, energy harvesting, environmental applications, and medicine due to their unique physiochemical properties. As nanomaterial use increases, so too does human exposure. This has made it progressively more important to understand the toxicological effects of nanomaterials and their interactions with the human body. Silver nanoparticles (AgNPs) are one of the most commonly used nanomaterials due to their antibacterial properties. As inhalation is one of the most common exposure routes, understanding the toxicity of these AgNPs on lung tissue was studied. Using A549 cells for a lung tissue …


Effect Of Activated Carbon On The Performance Of A Solar Thermal Adsorptive Refrigerator (Star) Using Activated Carbon-Ethanol, Joshua Romo Apr 2019

Effect Of Activated Carbon On The Performance Of A Solar Thermal Adsorptive Refrigerator (Star) Using Activated Carbon-Ethanol, Joshua Romo

Honors Theses

The Solar Thermal Adsorptive Refrigerator (STAR) project at the University of Dayton seeks to bridge sustainability and the need for reliable refrigeration in developing communities. Cost-effective construction, operation, and maintenance as well as the use of a sustainable adsorption pair, activated carbon-ethanol, give STAR great potential in the realm of humanitarian engineering. This project explores the effect of using two activated carbon brands, 8x16 and CocoPlus, on the cyclic performance of the STAR system. Although both brands have similar specifications given by the manufacturer, one (8x16) inhibited successful performance while the other (CocoPlus) enabled it. This project highlights both the …


Development Of A Simple Lab-Scale Vacuum Assisted Resin Transfer Molding (Vartm) Process, Donald A. Klosterman Oct 2018

Development Of A Simple Lab-Scale Vacuum Assisted Resin Transfer Molding (Vartm) Process, Donald A. Klosterman

Chemical and Materials Engineering Faculty Publications

The goal of the current study was to develop and demonstrate a simple and quick lab-scale VARTM process for the purpose of making flat panels for subsequent characterization, for example in new materials development efforts. This process was not intended to be optimized for final production, rather it served as the quickest way to make lab-scale composite panels using VARTM while maintaining all the salient features of typical VARTM processes used in larger scale manufacturing. There is a wide variety of ways to implement VARTM, as well as a diverse list of potential materials and supplies from which to choose. …


The Impact Of A Dynamic Environment On Deposition And Cellular Response To Silver Nanoparticles, Robert F. Uhrig Apr 2017

The Impact Of A Dynamic Environment On Deposition And Cellular Response To Silver Nanoparticles, Robert F. Uhrig

Honors Theses

Silver nanoparticles (AgNPs) are utilized in many different applications, such as an antibacterial agents or as protective coating against ultraviolet light. However, these AgNPs are known to cause potentially harmful biological effects, including toxicity, induction of stress, and immune activation. In this study, the effects of AgNPs on a human lung cell model were examined within both a static and dynamic environment. Most NP-based research is carried out in static environments, but do not accurate reflect dynamic physiological conditions. Dynamic fluid movement was introduced to the cell culture through the use of a multi-channel peristaltic pump. To further characterize the …


Failure Mechanism Of Woven Roving Fabric/Vinyl Ester Composites In Freeze–Thaw Saline Environment, Elias Anis Toubia, Sadra Emami, Donald A. Klosterman Nov 2016

Failure Mechanism Of Woven Roving Fabric/Vinyl Ester Composites In Freeze–Thaw Saline Environment, Elias Anis Toubia, Sadra Emami, Donald A. Klosterman

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

This experimental study investigates the degradation mechanisms of a glass fiber-reinforced plastic material commonly used in civil engineering applications. A substantial reduction in tensile, shear, and compression properties was observed after 100 days of freeze–thaw cycling in saline environment (-20°C to 20°C). Non-destructive inspection techniques were progressively conducted on unexposed (ambient condition) and exposed (conditioned) specimens. The dynamic mechanical analysis showed permanent decrease in storage modulus that was attributed to physical degradation of the polymer and/or fiber–matrix interface. This indicated the formation of internal cracks inside the exposed glass fiber-reinforced plastic laminate. The 3D X-ray tomography identified preferred damage sites …


Bioluminescent Magnetic Nanoparticles As Potential Imaging Agents For Mammalian Spermatozoa, Erick Salvador Vasquez, Jean M. Feugang, Scott T. Willard, Peter L. Ryan, Keisha B. Walters Jan 2016

Bioluminescent Magnetic Nanoparticles As Potential Imaging Agents For Mammalian Spermatozoa, Erick Salvador Vasquez, Jean M. Feugang, Scott T. Willard, Peter L. Ryan, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Background: Nanoparticles have emerged as key materials for developing applications in nanomedicine, nanobiotechnology, bioimaging and theranostics. Existing bioimaging technologies include bioluminescent resonance energy transfer-conjugated quantum dots (BRET-QDs). Despite the current use of BRET-QDs for bioimaging, there are strong concerns about QD nanocomposites containing cadmium which exhibits potential cellular toxicity.

Results: In this study, bioluminescent composites comprised of magnetic nanoparticles and firefly luciferase (Photinus pyralis) are examined as potential light-emitting agents for imaging, detection, and tracking mammalian spermatozoa. Characterization was carried out using infrared spectroscopy, TEM and cryo-TEM imaging, and ζ-potential measurements to demonstrate the successful preparation of these nanocomposites. Binding …


Influence Of Carbon Nanofillers On The Curing Kinetics Of Epoxy-Amine Resin, Luigi Vertuccio, Salvatore Russo, Marialuigia Raimondo, Khalid Lafdi, Liberata Guadagno Oct 2015

Influence Of Carbon Nanofillers On The Curing Kinetics Of Epoxy-Amine Resin, Luigi Vertuccio, Salvatore Russo, Marialuigia Raimondo, Khalid Lafdi, Liberata Guadagno

Chemical and Materials Engineering Faculty Publications

The cure kinetics of an epoxy resin based on the tetrafunctional epoxy precursor N,N′-tetraglycidyl methylene dianiline-(TGMDA) hardened with 4,4-diaminodiphenyl sulfone is investigated. The influence of carbon nanofillers (carbon nanotubes, carbon nanofibers, and graphene based nanoparticles) on the cure kinetic is studied. Kinetic analysis is performed by dynamic and isothermal differential scanning calorimetry (DSC).

In dynamic experiments, the activation energy was computed using an advanced isoconversional method while under isothermal conditions, the Kamal’s model of diffusion control was applied to simulate the systems throughout the curing process. The isothermal analysis shows that the introduction of the diluent decreases, …


The Role Of Biological Fluid And Dynamic Flow In The Behavior And Cellular Interactions Of Gold Nanoparticles, Emily K. Breitner, Saber M. Hussain, Kristen K. Comfort Sep 2015

The Role Of Biological Fluid And Dynamic Flow In The Behavior And Cellular Interactions Of Gold Nanoparticles, Emily K. Breitner, Saber M. Hussain, Kristen K. Comfort

Chemical and Materials Engineering Faculty Publications

Background: Due to their distinctive physicochemical properties, nanoparticles (NPs) have proven to be extremely advantageous for product and application development, but are also capable of inducing detrimental outcomes in biological systems. Standard in vitro methodologies are currently the primary means for evaluating NP safety, as vast quantities of particles exist that require appraisal. However, cell-based models are plagued by the fact that they are not representative of complex physiological systems. The need for a more accurate exposure model is highlighted by the fact that NP behavior and subsequent bioresponses are highly dependent upon their surroundings. Therefore, standard in vitro models …


Characterization Of Iron Phthalocyanine As The Cathode Active Material For Lithium-Ion Batteries, Sarwan S. Sandhu, Joseph P. Fellner Sep 2015

Characterization Of Iron Phthalocyanine As The Cathode Active Material For Lithium-Ion Batteries, Sarwan S. Sandhu, Joseph P. Fellner

Chemical and Materials Engineering Faculty Publications

The developed thermodynamic functions for the determination of Gibbs free energy, enthalpy, and entropy of formation of solid lithium-iron phthalocyanine (LixFePc) from solid lithium and iron phthalocyanine as a function of x, defined as g-moles of the intercalated lithium per g-mole of iron phthalocyanine, at a fixed set of temperature and pressure conditions are presented. In addition, a proposed expression for the evaluation of lithium diffusion coefficient in solid iron phthalocyanine as a function of both x and temperature, and the experimental results from the ongoing research/development work on the lithium/iron phthalocyanine cells are included.