Master of Science (MS), Ohio University, 2016, Mechanical Engineering (Engineering and Technology)

The aim of this work was to investigate the use of a catalytic material to accelerate the formation of carbonic acid in a thin liquid film using a vertical membrane mass transfer system. Results comparing the rate of formation of Total Inorganic Carbon (TIC) for similar experimental conditions between the non-catalytic and the catalytic mass transfer systems indicated a statistically significant increase in carbonic acid formation with catalytic mass transfer system. The increased rate of TIC accumulation in the media indicated that the catalytic galvanized mesh potentially accelerated the rate limiting step, i.e. the formation of carbonic acid on the thin liquid film.

Committee: David Bayless Ph.D., P.E., Fellow of ASME and NAI (Advisor); Gregory Kremer Ph.D. (Committee Member); Frank Kraft Ph.D. (Committee Member); Morgan Vis-Chiasson Ph.D. (Committee Member) Subjects: Chemical Engineering; Chemistry; Energy; Engineering; Environmental Engineering; Mechanical Engineering

Master of Science (MS), Ohio University, 2014, Mechanical Engineering (Engineering and Technology)

This research was conducted using a novel carbon capture and storage technology that involves the biosequestration of atmospheric CO2. Air with a controlled percentage of CO2, which simulates flue gas, is supplied into a temperature and pH controlled apparatus called the Photobioreactor (PBR). The PBR is circulated with a growth medium onto membranes, on which cultured cyanobacteria are used to fix the atmospheric CO2. The research measured and analyzed the effect of three different membranes on the liquid side mass transfer coefficient (kLa). Reverse Osmosis (RO) water was used instead of an algal growth medium in order to focus solely on analyzing the effect that surface morphology of a membrane material had on the kLa. The parameter kLa was calculated by measuring and recording the Total Inorganic Carbon (TIC) values at 30-second intervals during 20-minute trials. Data were statistical analyzed. The results showed that two of the three fabrics exhibited a higher kLa value. Micrographic images were captured to correlate the difference in kLa to the surface morphology.

Committee: David Bayless Ph.D (Advisor) Subjects: Mechanical Engineering

Master of Science (MS), Ohio University, 2024, Chemical Engineering (Engineering and Technology)

The objective of this research is to continue development of the flowtube, a new type of test equipment developed at the ICMT. Baseline testing is commonly used to validate models and ensure understanding of the electrochemical system. Baseline mass transfer experiments were performed using a rotating cylinder electrode (RCE). Baseline corrosion experiments were completed using an RCE as well as a rotating disk electrode (RDE). Mass transfer within the RDE system was also successfully modeled using computational fluid dynamics (CFD) software Ansys Fluent. Experimental and simulated results were validated using well known and accepted correlations. Validation of the CFD simulations is vital because no physical prototype for the flowtube currently exists to compare with the CFD results. The RDE simulations will serve as a baseline to prove that Fluent is capable of performing accurate mass transfer calculations and potentially future corrosion simulations. Current testing apparatuses for flowing environments tend to be large and/or difficult to use in a small-scale lab. To combat this, the flowtube cell can create a controlled single phase flow regime in a glass cell or autoclave and can test 3 samples at one time in its most recent revision. A new revision is currently being created, so the flowtube was modeled using CFD in order to determine how design alterations will affect the flowing environment within the glass cell. The flowtube hydrodynamics have been successfully modeled using Ansys Fluent. This model can illustrate fluid flow in the glass cell around the flowtube apparatus in both steady state and transient conditions. This model will continue to be expanded upon in the future to reflect the design considerations for the next prototype version. Design considerations and their impact on the hydrodynamics of the flowtube system were analyzed through this research.

Committee: Srdjan Nesic (Advisor); Marc Singer (Committee Member); Bruce Brown (Committee Member); Rebecca Barlag (Committee Member) Subjects: Chemical Engineering; Engineering; Fluid Dynamics

Master of Science, The Ohio State University, 1965, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1964, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1965, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1971, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1971, Graduate School

Committee: Not Provided (Other) Subjects:

MS, University of Cincinnati, 2023, Engineering and Applied Science: Chemical Engineering

The use of Membrane technology is extensively increasing in wastewater treatment and several other industries, due to its versatility, effectiveness, high removal capacity, and ability to meet multiple treatment objectives. Mathematical models have been developed for the different types of flow module configurations to estimate the overall performance of the module. The models are designed to give the output parameters such as the overall mass transfer coefficient and concentration of ammonia in the outlet stream. The mass transfer coefficients of ammonia through the hollow fiber membrane are calculated to understand the transport of ammonia from the liquid side to the strip side. Among the several existing models, the calculation of the overall mass transfer coefficient in this model was done using the penetration model, in which the penetration of the liquids into the pores on both sides of the membrane is considered and the mass transfer coefficients through the wetted pores are calculated. This model also accounts for the change in several input parameters such as temperature, pH, etc. The objective of this study is to understand and optimize the performance of the module for the degassing of ammonia. The performance or efficiency of the module depends on the type of flow configuration it employs and the stripping mechanism it uses to remove the extracted ammonia. The aim of the study is to compare the performances of these different flow configurations and different stripping methods under similar conditions. The effects of several input parameters such as pH, temperature, initial concentration, length of the module, feed flowrate, on the overall mass transfer coefficients, and removal efficiencies are important to understand to find out the optimal conditions for the module to operate. The effect of adding a dense membrane over the porous membrane is also studied in this (open full item for complete abstract)

Committee: Rakesh Govind Ph.D. (Committee Chair); Stephen Thiel Ph.D. (Committee Member); Anastasios Angelopoulos Ph.D. (Committee Member) Subjects: Chemical Engineering

MS, University of Cincinnati, 2023, Arts and Sciences: Biological Sciences

Though there are multiple lines of evidence that point to a mode of extracellular electron transfer (EET) in Methanosarcina barkeri, there is incomplete understanding of the mechanistic basis for this process. The goal of this Master's thesis is to investigate the protein basis of EET mechanisms in this microbe. In Chapter 1, the current evidence for EET in Methanogens and the state of knowledge for EET in M. barkeri are reviewed. Like other EET systems, it is predicted there is an extracellular protein conduit(s) that bridges the insulating cell envelope and connects the cell's internal redox machinery to the external electron source. However, the biophysical basis of this protein remains unknown. Part of the challenge for identifying such a protein is that the methanogen extracellular proteome is poorly characterized, complicating the search for the unknown protein conduit. To address this issue, in Chapter 2, a whole cell biotin-labeling technique was used to investigate the composition of the extracellular proteome of M. barkeri under methanol growth, poised potential electrochemical conditions, and open circuit control conditions. Combined, a total of 209 proteins was recovered from ten biotin-labeled samples and 48 from five non-biotin-labeled control samples. After accounting for potential non-specific binding, a list of 52 putatively extracellular proteins was curated from this work. Of these proteins, Fe-S oxidoreductase (Q46E87), ferritin-like diiron domain protein (Q46C50), and copper binding protein, plastocyanin/azurin family protein (Q466T4) were the main redox-active proteins of interest and may be worth further investigation regarding a potential role in EET. However, several proteins of unknown function were also identified, with some containing putative S-layer-like protein domains. DUF 1699 family proteins in particular may be worth further investigation, as they are highly conserved within Archaea. While this approach provides evidence of extrace (open full item for complete abstract)

Committee: Annette Rowe Ph.D. (Committee Chair); Amelia-Elena Rotaru Ph.D. (Committee Member); Dennis Grogan Ph.D. (Committee Member) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 2020, Translational Plant Sciences

The use of microbial inoculants to control plant disease is an increasingly used method in agriculture to mitigate damage caused by phytopathogens across a variety of systems. Best management practices to control many plant diseases can include use of multiple types of control measures in which biocontrol is one of a suite of tools used. One bacteria genus commonly investigated as biocontrol agents is Pseudomonas. These bacteria are known to be capable of promoting plant growth and reducing damage caused by disease though a variety of modes of action including nutrient competition and niche exclusion, secretion of antibiotic compounds including phenazines, DAPG, and pyoluteorin, and production of volatile organic compounds (VOCs). The primary focus of this dissertation, broadly, is the use of microorganisms (specifically Pseudomonas spp.) as biocontrol agents. Studies performed using these bacteria, both physically and conceptually, ranged from basic science, to small-scale microplot field trials, to applied market research. The focus of Chapters 2 and 3 of this work was investigating the role of VOCs in the biocontrol of nematodes (Caenorhabditis elegans) and fungi (Fusarium oxysporum) under in vitro conditions. The first objective of this work was to investigate how bacterial VOCs affected the growth and activity of other microorganisms, and determine what bioactive VOCs are produced by the bacteria. In shared-air indirect exposure assays using a diverse group of 20 bacteria (19 strains of Pseudomonas representing seven species and one of Pantoea agglomerans) we established that a majority the of the bacteria tested produced VOCs inhibitory to both C. elegans and F. oxysporum while other strains were only effective in inhibiting C. elegans. We performed VOC profiling using proton transfer reaction time-of-flight mass-spectrometry (PTR-ToF-MS) to compare differences in volatile production between the bioactive and non-bioactive strains. Hydrogen cyanide (HCN) (open full item for complete abstract)

Committee: Christopher Taylor PhD (Advisor); Joshua Blakeslee PhD (Committee Member); Michelle Jones PhD (Committee Member); Sally Miller PhD (Committee Member); Stephanie Strand PhD (Committee Member) Subjects: Plant Pathology; Plant Sciences

Doctor of Philosophy, University of Akron, 2020, Integrated Bioscience

Interfaces for air-mediated and evaporative transfer help process heat and substances in a variety of technical systems, from electronic to architectural. Because geometry affects the hydraulics, aerodynamic properties and thermal behavior of these devices, their performance can be tuned and passively enhanced through design. For biological interfaces such as plant leaves, geometry is also a determining factor in the exchange of gases, water management and thermal endurance against environmental exposures. Leaf shape, specifically, modulates the leaf's boundary layer, transpiration, evaporative cooling and convective exchange. In this body of work, design principles extracted from dissipative leaf morphologies were translated into varied evaporative structures (e.g. paper models, ceramic tiles, asphalt shingles). Multiple botanical and design studies were conducted to demonstrate the impact of planar dissection, edge extension, protrusion shape, elongation, scale and dimensionality on evaporative transfer, in controlled and outdoor environments. Overall, this research breaks new interdisciplinary ground and provides further insights into the interpretation of leaves as functionally shaped exchangers. The design outcomes illustrate the potential of leaf-inspired interfaces for thermoregulating the built environment. Ultimately, experimental biomimetics based on design studies with physical models is shown to provide a unique framework for innovating on evaporative technical exchangers.

Committee: Petra Gruber (Advisor); Hunter King (Committee Member); Peter Niewiarowski (Committee Member); Ali Dhinojwala (Committee Member); Junliang Tao (Committee Member) Subjects: Biophysics; Design; Plant Biology

Master of Science (MS), Ohio University, 2019, Mechanical and Systems Engineering (Engineering and Technology)

The aim of this study was to enhance a vertical rotating membrane system that induced gas to liquid mass transfer, and to evaluate its performance by quantifying its inorganic carbon formation rate under different parameters such as carbon dioxide concentration in air, membrane's rotational speed and the composition of the liquid medium. In addition to that, the ability of the zinc plated and nickel wire meshes to catalyze the hydration reaction of carbon dioxide was tested in this study using a bench scale rotating membrane system. The system was enhanced by replacing the mechanism that rotated the mass transfer membrane mesh by a simpler mechanism which depended on rollers to rotate the membrane mesh. Testing the enhanced system indicated that increasing the carbon dioxide concentration from 1% to 2%, from 1% to 10% and from 2% to 10% increased the system's inorganic carbon formation rate within the ranges of 69%-83%, 385%-521% and 179%-240% respectively. Furthermore, increasing the membrane's rotational speed from 70 rpm to 90 rpm resulted in increasing the inorganic carbon formation rate within a percentage range of 27%-38%. Also, the tests showed that using BG-11 as a test medium instead of DI water increased the inorganic carbon formation rate within a percentage range of 27%-33.3% when testing the rotating membrane system under 1% and 2% carbon dioxide concentrations respectively. Also, an increase of 7% was noticed when BG-11 medium was used as a medium instead of DI water under 10% carbon dioxide concentration in air. Moreover, results showed that using zinc plated and nickel wire meshes had no impact on catalyzing the carbon dioxide hydration reaction.

Committee: David Bayless (Advisor); Gregory Kremer (Committee Member); John Cotton (Committee Member); Sarah Davis (Committee Member) Subjects: Engineering

MS, University of Cincinnati, 2017, Engineering and Applied Science: Aerospace Engineering

Film cooling effectiveness can be measured by thermal and mass transfer analysis. We have designed and developed a flat plate adiabatic wind tunnel facility to study film cooling effectiveness of selected film hole geometries by mass transfer analysis using a heavy gas (CO2) as a substitute for the coolant, measuring the mixing by both gas sampling and full field measurements by an optical measurement technique using pressure/oxygen sensitive paint. The flat plate adiabatic wind tunnel consists of a 24” long by 1.5” x 4” rectangular duct with a 0.5” radiused inlet mounted on a 15.5” ID x 24.5” long mainstream air plenum. Air was supplied to one end of the mainstream air plenum and forced through flow straightening components such as a perforated metal plate and honeycomb layers exiting through the wind tunnel.Cooling flow (CO2) was injected into the mainstream air through film cooling holes in test coupons that are attached to the top surface of 1.5” x 4” x 3” high cooling plenum, mounted on an opening in the bottom surface of the wind tunnel, 5” from the duct inlet. The test coupons are 3” x 5.5” x 0.375” thick with a centrally reduced pocket of 2” x 4” x 0.17” thickness. The film cooling holes are of 0.1” diameter. The tests were run for three cases of round (cylindrical), inclined film cooling holes (25°, 30° and 35°) at a coolant to mainstream density ratio of 1.5 and a mainstream Mach number, M# of 0.14 with a Blowing ratio, M ranging from 0.5 to 2.0 in increments of 0.25. The mass concentrations of the coolant gas were measured at discrete locations downstream of coolant injection by bleeding gas samples through instrumentation taps and passing them through a gas (CO2) analyzer. Film cooling effectiveness was then calculated by mass transfer analysis using the coolant gas concentrations. The test facility was validated by comparing the results with published data. The effects of blowing ratio and other flow parameters on film cooling effectiveness were studied (open full item for complete abstract)

Committee: Ephraim Gutmark Ph.D. (Committee Chair); Shaaban Abdallah Ph.D. (Committee Member); Jeffrey Kastner Ph.D. (Committee Member) Subjects: Aerospace Materials

Master of Science in Chemical Engineering, Cleveland State University, 2017, Washkewicz College of Engineering

Air separation using zeolite based adsorption processes is a widely-studied topic. Proper process modeling is a key requirement to simulate the process. Conventional process modeling for air separation is designed for large scale adsorption processes using a long cycle time. However, advanced technology now permits to use of a short cycle time using small particles, which significantly reduces the size of the process. Traditional process models were mostly developed for large particles (dp > 1.5 mm). Typically, it is safely assumed that intra particle diffusion controls the rate of the process while axial dispersion has a much smaller effect. This is a safe assumption since a long diffusional path exists inside the large particles. The diffusional path inside the small particles (dp> 0.5 mm) is reduced significantly. In addition, smaller particle size increases specific particle surface area which reduces the effect of film resistance. Hence, effect of axial dispersion is more significant for process modeling with small particles. The primary objective of this thesis is to determine the impact of external diffusion to the particles in the process. In this study, breakthrough experiments are utilized to understand the behavior of mass transfer in small particles. Mass transfer zone length is measured from breakthrough experiments at different velocities and pressures to identify the effect of axial dispersion in small particles. This thesis demonstrates two important parameters that utilized in determining extent of axial dispersion. depends on the level of adsorbent-adsorbate interaction and represents the level of eddy diffusion in the process. Typical value of 0.7 and 0.5 are assumed for and respectively for large particles. In this study, and are evaluated experimentally using mass transfer zone curve for small particles are 13 and 9 respectively. Comparison between parameter values for large and small particles is varies significantly, which ul (open full item for complete abstract)

Committee: Orhan Talu Ph.D. (Advisor); Rolf Lustig Ph.D. (Committee Member); Sasidhar Gumma Ph.D. (Committee Member) Subjects: Chemical Engineering

Doctor of Philosophy, The Ohio State University, 2017, Food, Agricultural and Biological Engineering

Solid-state anaerobic digestion (SS-AD) can be used to convert abundant, low moisture feedstocks, such as switchgrass, to methane (CH4)-rich biogas. However, biogas is a gas under ambient conditions, and impurities need to be removed before it can be upgraded to other products. Integration of SS-AD with biological conversion of biogas to methanol could provide an environmentally friendly method to convert renewable feedstocks to liquid chemicals. The first project showed that limited air exposure had a minimal effect on SS-AD of switchgrass, and thermophilic conditions (55°C) improved biogas yields (102–145 L CH4 kg VSadded-1) compared to mesophilic (37°C) (88–113 L CH4 kg VSadded-1). Net energy analysis of a theoretical “garage-type” SS-AD reactor suggested that positive net energy could be obtained at elevated total solids contents (= 20% TS). A new methanotroph strain (Methylocaldum sp. 14B) was isolated from the digestate of a mesophilic SS-AD reactor. Strain 14B successfully converted biogas to methanol using phosphate as a methanol dehydrogenase (MDH) inhibitor and formate as an electron donor. The maximum methanol concentration (0.43±0.0 g/L) and CH4 to methanol conversion ratio (25.5±1.8%) were obtained using strain 14B suspended in NMS medium containing 50 mM phosphate and 80 mM formate a biogas:air ratio of 1:2.5 (v/v). Abiotic gas-liquid mass transport of O2 in a trickle-bed reactor (TBR) packed with ceramic balls was two times higher than an unpacked TBR. The results suggested that the TBR enhanced gas oxidation compared to shake flasks. Maximum methanol productivity (0.9 g/L/d) in the non-sterile TBR was obtained at 12 mmol formate and 3.6 mmol phosphate and a biogas:air ratio of 1:2.5. Operation under non-sterile conditions impacted the microbial community of the TBR. A mathematical model that considered mass transport and gas consumption kinetics was used to generate results that were similar to selected semi-batch data from the lab-s (open full item for complete abstract)

Committee: Jay Martin PhD (Advisor); Gonul Kaletunc PhD (Committee Member); Ajay Shah PhD (Committee Member); Zhongtang Yu PhD (Committee Member) Subjects: Agricultural Engineering; Alternative Energy; Environmental Science

Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1980, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1968, Graduate School

Committee: Not Provided (Other) Subjects: Engineering