Current Search: Undergraduate Honors Theses (x) » Department of Chemical and Biomedical Engineering (x)
Search results
(1 - 10 of 10)
- Title
- Effect of Conductivity Solution Salt Type on the Formation of Hydrogen Peroxide in a Low Power Gas-Liquid Plasma.
- Creator
-
Seshie, Delanyo, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
In this study, several of the conditions that affect the formation of hydrogen peroxide in a tubular plasma reactor were analyzed. Specifically, the initial conductivities of the inlet deionized water and the type of salt solutions introduced into the tubular plasma reactor were studied. In analysis of each of these variables, the production rate and concentration of hydrogen peroxide, the power, current and voltage waveforms, energy yield for the process, and final outlet solution...
Show moreIn this study, several of the conditions that affect the formation of hydrogen peroxide in a tubular plasma reactor were analyzed. Specifically, the initial conductivities of the inlet deionized water and the type of salt solutions introduced into the tubular plasma reactor were studied. In analysis of each of these variables, the production rate and concentration of hydrogen peroxide, the power, current and voltage waveforms, energy yield for the process, and final outlet solution conductivity were measured and analyzed. The initial study involved altering the initial solution conductivity using salts of sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl2), and calcium chloride (CaCl2). Preliminary studies were also conducted on the effects of the temperature of the deionized water delivered into the reactor. With respect to analysis of conductivities, the results obtained show that the production rate of hydrogen peroxide and energy yield decreased with an increase in conductivity for all salts. For deionized water with an initial conductivity of 1.98μS/cm, better results were obtained in comparison to salt solutions. The production rate and concentration of H2O2 were approximately 0.12 μmol/s and 9.4 mM, respectively. The power and energy yield under the same conditions were 0.70 W and 20 g kW-1·h-1, respectively. In contrast, the best result obtained for conductive solutions was with NaCl solution at 84 μS/cm. The production rate and energy yield were 0.050 μmol/s and 6.8 g kW-1·h-1, respectively. Moreover, the study involved analyzing the effects of salts in the same period but different groups, i.e. K+ and Ca2+, as well as Na+ and Mg2+. It was found that although the solutions with monovalent cations had lower production rates of H2O2, the energy yield for these solutions were higher than the corresponding solutions with divalent cations. The plausible explanation for this result was the ionic mobilities of the cations.
Show less - Date Issued
- 2014
- Identifier
- FSU_migr_uhm-0350
- Format
- Thesis
- Title
- Effectiveness of Recycled N-Methylmorpholine N-Oxide as a Pretreatment Solvent on Agricultural Wastes.
- Creator
-
Wilson, Cory, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
For this study, multiple experiments were performed on corn stover and sugarcane bagasse, in which cellulosic conversion yields using a novel dual-stage pretreatment process (dilute acid, followed by NMMO dissolution, named DAWNT) was compared to yields obtained with independent treatments of each at different conditions. Moreover, the dual-stage treatment using fresh NMMO to dissolve the dilute acid treated corn stover was compared to the same process using recycled NMMO. Results have shown...
Show moreFor this study, multiple experiments were performed on corn stover and sugarcane bagasse, in which cellulosic conversion yields using a novel dual-stage pretreatment process (dilute acid, followed by NMMO dissolution, named DAWNT) was compared to yields obtained with independent treatments of each at different conditions. Moreover, the dual-stage treatment using fresh NMMO to dissolve the dilute acid treated corn stover was compared to the same process using recycled NMMO. Results have shown that the DAWNT process is able to achieve nearly complete digestion of the cellulosic fraction within corn stover and roughly 90% digestion within sugarcane bagasse in 48 hour reaction times with low enzyme concentrations of 10 mgprotein/gglucan. These results were obtained for corn stover at 1 hour and 3 hour NMMO treatment times, while sugarcane bagasse was for a treatment time of only 3 hours. The nearly completely digested corn stover using the DAWNT process is an improvement from 83% (for dilute acid treatment only), 58% (for NMMO treatment only), and 21% (for untreated) after 72 hours reaction time. In addition, it has been shown that recycled NMMO is able to effectively enhance glucan conversion consistently over the course of 3 recycles (used in 4 treatments), to the same degree as was found for the DAWNT results for corn stover using fresh NMMO. Over 97% of the NMMO has been recovered from each recycle, with an overall solvent recovery (after its use in 4 treatments) of 86%.
Show less - Date Issued
- 2013
- Identifier
- FSU_migr_uhm-0170
- Format
- Thesis
- Title
- Electrochemical Reduction of Co2 Using Cu Catalyst Prepared by Electroless Deposition.
- Creator
-
Ethier, Jeffrey, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
Electroless copper electrocatalyst deposited on carbon Toray paper at varying deposition times was evaluated for possible use in electrochemical reduction of carbon dioxide. The results obtained indicate that the electrochemical reduction of carbon dioxide is feasible using the fabricated electrodes prepared by the electroless deposition method. XRD analysis showed that all the electroless Cu deposits exhibit four major reflection planes (111), (200), (220), and (311) with as (111) the...
Show moreElectroless copper electrocatalyst deposited on carbon Toray paper at varying deposition times was evaluated for possible use in electrochemical reduction of carbon dioxide. The results obtained indicate that the electrochemical reduction of carbon dioxide is feasible using the fabricated electrodes prepared by the electroless deposition method. XRD analysis showed that all the electroless Cu deposits exhibit four major reflection planes (111), (200), (220), and (311) with as (111) the dominant peak. The particle size of the deposit increased non-linearly with deposition time. The solubility and diffusivity of the electrochemically active species in 0.5 M NaHCO3 were determined by electrochemical technique and are reported as 6.59 x 10-5 mol/cm3 and 4.47 x 10-10 cm2/s, respectively. Based on ideal case of single electrode reaction for the formation of the different CO2 reduction products, it is suggested that larger nanoparticle size favors production of hydrocrabons and formation of CO.
Show less - Date Issued
- 2014
- Identifier
- FSU_migr_uhm-0329
- Format
- Thesis
- Title
- Enzymatic Hydrolysis Kinetics: The Study of the Effects of Glucose on the Conversion of Cellulose to Glucose.
- Creator
-
Tacey, Sean, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
(Cellulose, Enzymes, Biofuels) The conversion of cellulose to glucose is one renewable energy strategy under consideration, for glucose can also serve as a feed stock for ethanol and other chemicals currently produced from petroleum. Within sugar production through enzymatic hydrolysis, many steps are believed to occur; this includes the initial adsorption of enzyme onto a cellulose chain, the binding of the enzyme to an accessible site on the chain, the reaction severing the chain, and the...
Show more(Cellulose, Enzymes, Biofuels) The conversion of cellulose to glucose is one renewable energy strategy under consideration, for glucose can also serve as a feed stock for ethanol and other chemicals currently produced from petroleum. Within sugar production through enzymatic hydrolysis, many steps are believed to occur; this includes the initial adsorption of enzyme onto a cellulose chain, the binding of the enzyme to an accessible site on the chain, the reaction severing the chain, and the motion of the enzyme to another site. Measuring changes that occur during these steps is difficult, but one can separate the adsorption step from the chain removal steps using precise measurements of the mass of well-defined cellulose films. A device that can measure the nanogram amounts of enzyme adsorbed onto a cellulose surface and the change in mass of adsorbed material with time is invaluable in this study; a quartz crystal microbalance (QCM), used in this work, has this potential. Glucose has been found to act as an inhibitor to the overall reaction. Through the QCM, the effects of various glucose concentrations in the enzyme mixture were studied to determine the type of inhibition occurring. While our data seems to show some effects of glucose on the enzymatic process, a statistical analysis of all of the data shows no significant effect on either the enzyme adsorption step or the chain breaking. This gives us reason to believe that the real inhibitory effect of glucose is on the homogeneous reaction that produces glucose from cellobiose.
Show less - Date Issued
- 2014
- Identifier
- FSU_migr_uhm-0360
- Format
- Thesis
- Title
- Lanthanide-Encapsulated Single-Walled Carbon Nanotubes for Transplantable Cell Monitoring at High Magnetic Field.
- Creator
-
Hampe, Alexander, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
The use of nanoparticles as intracellular contrast agents for magnetic resonance imaging (MRI) has been explored in recent years at clinical magnetic field strengths. Lanthanides such as gadolinium and dysprosium are ideal for enhancing contrast because of their paramagnetic properties. When encapsulated by ultra-short single-walled carbon nanotubes (SWNTs), MR relaxivity may be significantly improved. These particles may be suitable for intracellular labeling of human mesenchymal stem cells ...
Show moreThe use of nanoparticles as intracellular contrast agents for magnetic resonance imaging (MRI) has been explored in recent years at clinical magnetic field strengths. Lanthanides such as gadolinium and dysprosium are ideal for enhancing contrast because of their paramagnetic properties. When encapsulated by ultra-short single-walled carbon nanotubes (SWNTs), MR relaxivity may be significantly improved. These particles may be suitable for intracellular labeling of human mesenchymal stem cells (hMSCs) in the treatment of stroke. The delivery of these stem cells to areas of ischemic injury has been shown to facilitate angiogenesis and neurogenesis. High magnetic field strengths may further augment detectability of labeled cells, enabling implanted cells to be tracked in vivo. Additionally, the route of delivery (intravenous, intra-arterial, intranasal) of hMSCs may impact cell engraftment and stroke recovery. The aim of this study was to evaluate the relaxivity potential of both gadolinium- and dysprosium-encapsulated nanotubes at varying magnetic field strengths, as well as the transplantation of SWNT-labeled hMSCs in ischemic rats, with multiple methods of delivery considered. Results from T2- and T2*-weighted in vitro images of labeled hMSCs indicate that dysprosium-encapsulated SWNTs reduce transverse relaxation times, but cellular uptake may be limited to levels below the experimental concentrations. Scans performed in vivo suggest that SWNTs may not be as suitable for hMSC labeling compared to other nanoparticles. Additional experimentation is necessary for determining optimal SWNT loadings and delivery methods, relaxometric measurements on gadolinium-encapsulated SWNTs, and effects on cell viability, differentiation, and gene expression.
Show less - Date Issued
- 2014
- Identifier
- FSU_migr_uhm-0414
- Format
- Thesis
- Title
- MR Quantitative Susceptibility Mapping: A Potential Analysis of Metal Content in Neurodegenerative Brain.
- Creator
-
Chin, Adam, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
Many neurodegenerative diseases have neither a cure nor a clear delineation of causation at the root of the pathology. However, several neurological diseases do present significant metal deposition that gradually increases with the progression and evolution of the disease. For example, a characteristic of certain amyloid related neuropathologies, such as Alzheimer's and Parkinson's diseases, is not only the presence of beta amyloid plaques and neurofibrillary tangles but also the accumulation...
Show moreMany neurodegenerative diseases have neither a cure nor a clear delineation of causation at the root of the pathology. However, several neurological diseases do present significant metal deposition that gradually increases with the progression and evolution of the disease. For example, a characteristic of certain amyloid related neuropathologies, such as Alzheimer's and Parkinson's diseases, is not only the presence of beta amyloid plaques and neurofibrillary tangles but also the accumulation of metals, particularly iron, co-localized with these hallmarks. Quantitative susceptibility mapping (QSM) is a fairly new post-processing method that provides a map of the distribution of magnetic susceptibilities across tissue based on the perturbation of the main magnetic field used to generate an MR image. As such, QSM techniques should be sensitive not only to underlying differences in the material properties of tissues and structures but also to pathological depositions of metals that could have diagnostic relevance as early biomarkers. This preliminary study evaluated the effectiveness of QSM coupled with high magnetic fields to provide a useful, non-invasive technique to assess brain tissue composition and assess end-stage neurodegeneration.
Show less - Date Issued
- 2013
- Identifier
- FSU_migr_uhm-0159
- Format
- Thesis
- Title
- The Role of Alpha-7 Nicotine Acetylcholine Receptors in Angiogenesis After In Vivo Nicotine Administration.
- Creator
-
Rodriguez, Monica, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
Coronary Heart Disease (CHD) is one of the deadliest heart diseases in the United States. CHD is described as the narrowing of capillaries. Risk factors that contribute to this disease are smoking and stress. In the Cappendijk Lab, the effects of nicotine are studied in zebra finches, an established model to study cognitive processes. Nicotine acts on nicotinic acetylcholine receptors (nAChRs) to induce effects. Of interest are alpha-7 nAChRs, which are involved in cognitive processes and...
Show moreCoronary Heart Disease (CHD) is one of the deadliest heart diseases in the United States. CHD is described as the narrowing of capillaries. Risk factors that contribute to this disease are smoking and stress. In the Cappendijk Lab, the effects of nicotine are studied in zebra finches, an established model to study cognitive processes. Nicotine acts on nicotinic acetylcholine receptors (nAChRs) to induce effects. Of interest are alpha-7 nAChRs, which are involved in cognitive processes and found on endothelial heart cells (ECs). The number of ECs is positively linked with the process of angiogenesis. Angiogenesis is a physiological process for cell survival and development. There are indications that alpha-7 nAChRs on ECs are a target for revascularization in therapeutic angiogenesis of heart disease. During angiogenesis an increased expression of heat shock protein (HSP) 70, is observed. The aim of the project was to identify the role of alpha-7 nAChRs and HSP70 in angiogenesis in the adult male zebra finch heart following single and repetitive administrations of nicotine. We found that alpha-7 nAChR expression and wall thickness increased in nicotine-exposed animals immediately after nicotine (single and repetitive) treatment. Wall thickness increased only in mid-sized vessels 3 months (long-term) following the cessation of nicotine, but not after 24hr withdrawal from nicotine. The expression of HSP70 was dependent on vessel size (diameter) and decreased after repetitive exposures to nicotine. These results suggest that nicotine could induce a long-term effect on heart tissue and the process of angiogenesis in the adult male zebra finch.
Show less - Date Issued
- 2012
- Identifier
- FSU_migr_uhm-0059
- Format
- Thesis
- Title
- A Simplified Protein Folding Simulation Using a Metropolis Monte Carlo Algorithm.
- Creator
-
Franklin, Robert D., Department of Chemical and Biomedical Engineering
- Abstract/Description
-
The major outcome of this project is "Protein Folding Toy," an iPad program (app) which is designed to allow children (ages 10-18) to interact with a system that behaves like a single polymer chain on the molecular level. The user can design a single chain, specifying a sequence of beads that each could be neutral (black), hydrophobic (green), or charged (red/blue). The app can then perform a Metropolis Monte Carlo simulation and allows the user to vary temperature in real time. Observed...
Show moreThe major outcome of this project is "Protein Folding Toy," an iPad program (app) which is designed to allow children (ages 10-18) to interact with a system that behaves like a single polymer chain on the molecular level. The user can design a single chain, specifying a sequence of beads that each could be neutral (black), hydrophobic (green), or charged (red/blue). The app can then perform a Metropolis Monte Carlo simulation and allows the user to vary temperature in real time. Observed chain behavior depends on inter-bead interactions as well as temperature-dependent stochastic motions.
Show less - Date Issued
- 2015
- Identifier
- FSU_migr_uhm-0521
- Format
- Set of related objects
- Title
- A Study of Glucose as an Inhibitor to the Enzymatic Hydrolysis of Cellulose Using a Quartz Crystal Microbalance.
- Creator
-
Quintanilla, Adam, Department of Chemical and Biomedical Engineering
- Abstract/Description
-
Cellulose derived from lignocellulose has become the focus of many groups globally as a potential replacement for biofuel feedstock production. The most important step involved in this process is the enzymatic hydrolysis of cellulose. The Quartz Crystal Microbalance (QCM) has recently shown value in its ability to analyze hydrolysis in real time while controlling important reaction variables. The two main points of interest are the mass of enzyme bound to cellulose and the rate at which it is...
Show moreCellulose derived from lignocellulose has become the focus of many groups globally as a potential replacement for biofuel feedstock production. The most important step involved in this process is the enzymatic hydrolysis of cellulose. The Quartz Crystal Microbalance (QCM) has recently shown value in its ability to analyze hydrolysis in real time while controlling important reaction variables. The two main points of interest are the mass of enzyme bound to cellulose and the rate at which it is removed by enzymes. Hydrolysis was run at three enzyme concentrations: 0.0613 FPU/mL, 0.1247 FPU/mL, and 0.2475 FPU/mL. It has been also shown in multiple studies that glucose could be acting as an inhibitor to cellulase. Four glucose concentrations were observed at each enzyme concentration: 1 mg/mL, 2 mg/mL, 5 mg/mL, and 10 mg/mL. Analysis of the data revealed that there was a significant relationship between enzyme concentration and both the mass of enzyme bound and the rate of removal. The effects were determined to not be linear in nature, but more likely follow a model which suggests a maximum possible binding and rate. The effect of glucose on enzyme binding was insignificant due to large standard deviations seen amongst all conditions. This insignificance was strengthened by a two-way analysis of variance which revealed that the data collected was not repeatable. The overall effect of glucose on hydrolysis rates was negative in that rates generally decreased. The type of inhibition was determined to be competitive using an inverse rate plot versus glucose concentration.
Show less - Date Issued
- 2013
- Identifier
- FSU_migr_uhm-0179
- Format
- Thesis
- Title
- Studying Voltage Stability of Polymer Electrolyte on Planar Metal Electrodes.
- Creator
-
Rausch, Alexander D., Department of Chemical and Biomedical Engineering
- Abstract/Description
-
Lithium batteries offer high energy density, high capacity, and long cycle life. However, these batteries use dangerous organic solvents in the electrolytes that can lead to malfunction, fires, and explosions. Polymer electrolytes are being used to replace these dangerous organic solvents as safer alternatives. In order for polymer electrolytes to become commercially feasible, they must be stable at high voltages. This project aims to determine the voltage stability of solid polymer...
Show moreLithium batteries offer high energy density, high capacity, and long cycle life. However, these batteries use dangerous organic solvents in the electrolytes that can lead to malfunction, fires, and explosions. Polymer electrolytes are being used to replace these dangerous organic solvents as safer alternatives. In order for polymer electrolytes to become commercially feasible, they must be stable at high voltages. This project aims to determine the voltage stability of solid polymer electrolyte with different metal current collectors for use in solid-state lithium batteries. In particular, it focuses on poly(ethylene oxide) (PEO) doped with lithium bis-triflouromethanesulfonimide salt (LiTFSI) as the electrolyte at a molar ratio of 0.085 mol(Li+)/mol(EO). Also, polystyrene - b - poly(ethylene oxide) block copolymer (SEO) was studied with LiTFSI. Copper, aluminum, and gold are used as the various working electrodes, and lithium is used as the counter electrode. Impedance spectroscopy is used to verify that the half-cells are well assembled by comparing the conductivity to literature values. Voltammetry is used to characterize the voltage stability of the electrolyte in the different half-cell assemblies. Aluminum electrodes experienced corrosion at potentials above 3.5 V. Au and Cu experienced an electrolyte degradation reaction with an onset potential of 3.16 V. There is strong evidence suggesting the degradation reaction rate is influenced by mass transport and Ohmic limitations.
Show less - Date Issued
- 2015
- Identifier
- FSU_migr_uhm-0458
- Format
- Thesis
