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Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal
Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal
Browse all Theses and Dissertations
Since their invention in 1958, Integrated Circuits (ICs) have become increasingly more complex, sophisticated, and useful. As a result, they have worked their way into every aspect of our lives, for example: personal electronic devices, wearable electronics, biomedical sensors, autonomous driving cars, military and defense applications, and artificial intelligence, to name some areas of applications. These examples represent both collectively, and sometimes individually, multi-trillion-dollar markets. However, further development of ICs has been predicted to encounter a performance bottleneck as the mainstream silicon industry, approaches its physical limits. The state-of-the-art of today’s ICs technology will be soon below 3nm. At such …
Rheological Modeling And Inkjet Printability Of Electrode Ink Formulation For Miniature And Interdigital Lithium-Ion Batteries, Habib Temitope-Adebayo Ajose
Rheological Modeling And Inkjet Printability Of Electrode Ink Formulation For Miniature And Interdigital Lithium-Ion Batteries, Habib Temitope-Adebayo Ajose
Browse all Theses and Dissertations
The rapid advancement of technology has resulted in a greater need for effective energy storage systems to meet the demands of the transportation and electronics industries. Among various energy storage systems, batteries are the most widely used, primarily because of their ability to store significant amounts of energy. In addition, lithium-ion batteries are prevalent for powering portable electronic devices due to their long cycle life, high energy density, and high operating voltage. The traditional doctor-blade approach has been used over the years for producing batteries. Currently, research is being directed to additively manufacture Li-ion batteries via Drop-on-Demand Inkjet Printing with …
Economic Feasibility Of A Methanol To Dimethyl Ether Production Process To Avoid Contract Failure Shortfalls From The Covid-19 Pandemic, Jacob Noll, Robert Wasson, Harrison Mckinnis
Economic Feasibility Of A Methanol To Dimethyl Ether Production Process To Avoid Contract Failure Shortfalls From The Covid-19 Pandemic, Jacob Noll, Robert Wasson, Harrison Mckinnis
Honors Theses
Our team entered the 2021 AVEVA Academic Competition, where teams of undergraduate senior chemical engineering students competed across the country. The competition was composed of two parts: the base case design and the optimization of a chemical process. As part of the competition, our team is acting as the Engineering team for a fictional company that has given us this project. Due to COVID-19, our methanol producing company has lost a contract with a customer, leaving 23,000 tonnes/yr of unclaimed methanol. We have two choices with this methanol: either sell the methanol on the market at the spot price for …
Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee
Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee
Multidisciplinary Studies Theses and Dissertations
Accomplishing slow translocation speed with high sensitivity has been the greatest mission for solid-state nanopore (SSN) to electrically detect nucleobases in single-stranded DNA (ssDNA). In this study, a method to detect nucleobases in ssDNA using a SSN is introduced by considerably slowing down the translocation speed and effectively increasing its sensitivity. The ultra-thin titanium dioxide (TiO2) coated hexagonal boron nitride (h-BN) nanopore was fabricated, along with an ionic-liquid [bmim][PF6]/2.0 M KCl aqueous (cis/trans) interfacial system, to increase both the spatial and the temporal resolutions. As the ssDNA molecules entered the nanopore, a …
Engineering Dopant Position In Structure-Controlled Ceo2-Zro2 Catalysts, Behnam Safavinia
Engineering Dopant Position In Structure-Controlled Ceo2-Zro2 Catalysts, Behnam Safavinia
LSU Master's Theses
CeO2-ZrO2 (CZO) nanoparticles (NPs) have application in many catalytic reactions, such as methane reformation, due to their oxygen cycling ability. Ni doping has been shown to improve the catalytic activity and acts as an active site for the decomposition of methane. In this work, Ni:CZO NPs were synthesized via a two-step co-precipitation/molten salt synthesis to compare Ni distribution, oxygen vacancy concentration, and catalytic activity relative to a reference state-of-the-art catalyst. To better understand the effects of Ni position and dispersion, and oxygen vacancy formation in these materials, the Ni concentration, reaction time, and deposition methods were varied. …
Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle
Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle
Browse all Theses and Dissertations
Fused silica (silica glass) is transparent in the optical and near-infrared and has a low dielectric constant, making it suitable as a window material for radio frequency radiation. However, at high temperatures (>1100C), fused silica will easily creep and lose dimensional stability. Crystallized silica is much more creep resistant than fused silica. Silica crystallizes to many different structures including quartz, tridymite, and α- and β cristobalite. The only cubic polymorph, which is suitable for both optical and radio frequency transmission in polycrystalline form, is β -cristobalite. Unfortunately, this polymorph transforms to α-cristobalite at ~300C, and the volume change during …
Development And Analysis Of A Methanol-To-Gasoline Reaction Setup For Use In An Undergraduate Setting, Ryan Michael Beere
Development And Analysis Of A Methanol-To-Gasoline Reaction Setup For Use In An Undergraduate Setting, Ryan Michael Beere
Graduate Theses - Chemical Engineering
The primary goal of this research was to develop a framework for a setup for use in an undergraduate laboratory setting to study catalyzed reactions. A setup was developed with packed ZSM-5 catalyst for the Methanol-to-Gasoline (MTG) reaction. This research demonstrates and explains some of the trends that can be observed in catalytic reactions based on the effects of various process variables that can be used in a unit operations laboratory. Process conditions such as temperature, particle diameter, and nitrogen flow rate were studied. The temperature trials confirmed that 375 °𝐶 was the optimal temperature for methanol conversion. Selectivity towards …
Catalytic Waste Gasification: Water-Gas Shift & Selectivity Of Oxidation For Polyethylene, Mason J. Lang
Catalytic Waste Gasification: Water-Gas Shift & Selectivity Of Oxidation For Polyethylene, Mason J. Lang
ETD Archive
As landfills approach capacity and take up valuable land space, metropolitan areas have realized the need for waste disposal alternatives. Thus, there has been a widespread use of waste incinerators in Europe and the United States [1]; [2]. Although newer technology has made incinerators more efficient, there is an increasing interest in formulating `greener’ alternatives to incinerators. Gasification converts organic and carbonaceous materials into a combination of gaseous products known as “syngas,” or synthetic gas. This process greatly reduces the amount of hazardous emissions. The syngas produced by gasifiers has a wide range of uses, including their conversion into diesel, …
Adsorption Induced Solid Phase Transition Of Mil-53(Al), Rushik G. Bandodkar
Adsorption Induced Solid Phase Transition Of Mil-53(Al), Rushik G. Bandodkar
ETD Archive
Metal organic frameworks (MOFs) are nano-porous solids with potential applications in a wide range of fields including gas separation and catalysis. A number of metal organic frameworks show structural transformation and exceptional flexibility on changing the temperature, pressure and adsorption of certain guest molecules. On the contrary, most of the porous solids like zeolites and activated carbon used in applications are rigid. The structural flexibility makes MOF materials very interesting to study and show promise in applications such as sensors, actuators, membrane separation and adsorptive separation. In this study, we examine the chemical potential difference (Δμ) of MIL-53 (Al), a …
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
ETD Archive
Magnetophoresis of red blood cells (RBCs) at varying partial pressures of oxygen (pO2) is hypothesized to rejuvenate stored blood to be utilized beyond the FDA regulated 42-day storage time. Magnetophoresis is a particle or cells motion induced by an applied magnetic field in a viscous media. The average magnetophoretic mobility of an oxygenated RBC is -0.126x10-6 mm3-s/kg, and a deoxygenated RBC is 3.66x10-6 mm3-s/kg, presenting magnetophoresis as a resource for RBC rejuvenation in hopes of storing it longer than 42 days. The main objective of this paper was to determine if controlling the pO2 within an RBC suspension, can singly- …
Chronoamperometry Analysis Of Sweat Sensor Technology, Evan Fritz
Chronoamperometry Analysis Of Sweat Sensor Technology, Evan Fritz
Williams Honors College, Honors Research Projects
Due to the demand for in-situ electrolyte sodium sensors, prototype sensors have been produced to create a product for athletes and marathoners to monitor hydration levels. These senors address a desire in the marketplace for athletic monitoring for overall athlete wellness and performance. Sweat sensor samples were created using Multi-walled Carbon Nanotubes functionalized on a Nylon-6 fiber mat using cyclo-oligomeric Calixarene. This production process produces sensors capable of detecting sodium ion concentration present in human sweat in presence of an electric current. Chronoamperometry analysis is used in this manner to determine the functionality of the sensors. Much of the research …
Extrusion-Based Direct Write Of Functional Materials From Electronics To Magnetics, Alan Shen
Extrusion-Based Direct Write Of Functional Materials From Electronics To Magnetics, Alan Shen
Doctoral Dissertations
New micro- and nanoscale fabrication methods are of vital importance to drive scientific and technological advances in electronics, materials science, physics and biology areas. Direct ink writing (DW) describes a group of mask-less and contactless additive manufacturing (AM), or 3D printing, processes that involve dispensing inks, typically particle suspensions, through a deposition nozzle to create 2D or 3D material patterns with desired architecture and composition on a computer-controlled movable stage. Much of the functional material printing and electronics area remains underdeveloped for this new technology. There is a need to understand and establish the advantages and shortcomings of extrusion-based DW …
Application Of A Light Switchable System In Redirecting Escherichia Coli Metabolic Fluxes, Xintong Xia
Application Of A Light Switchable System In Redirecting Escherichia Coli Metabolic Fluxes, Xintong Xia
Graduate Theses - Chemical Engineering
Optogenetics has gained increasing attention for enabling reversible and non-invasive control in biochemical engineering. The purpose of this project is to investigate the application of a genetically engineered light-switchable system, Cph8-OmpR, for controlling the accumulation of the useful central metabolite glucose-6-phosphate (G6P) in Escherichia coli. This could be accomplished by linking expression of an adaptor protein, SspB, which increases enzyme phosphofructokinase (Pfk) degradation, with different light intensities. Pfk is the enzyme that catalyzes the conversion of fructose-6-phosphate (F6P), an isomer of G6P from an equilibrium reaction, to fructose 1,6-biphosphate for downstream metabolism. This step is considered the major control point …
Optimization Of The Production Of Long-Chain Dicarboxylic Acids From Distillers Corn Oil Using Candida Viswanathii, Jennifer Ann Mobley
Optimization Of The Production Of Long-Chain Dicarboxylic Acids From Distillers Corn Oil Using Candida Viswanathii, Jennifer Ann Mobley
Graduate Theses - Chemical Engineering
This thesis explores the viability of using the yeast Candida viswanathii to convert distillers corn oil, a byproduct of the ethanol industry, into long-chain α,ω-dicarboxylic acids used in lubricants, cosmetics, and biopolymers. Glucose, xylose, and glycerol were used as carbon sources for the determination of growth parameters of this strain, of which it was found that growth on glucose resulted in the highest specific growth rate of 0.482 hr-1 and the lowest biomass yield coefficient of 0.566 - 0.754 g DCW per g substrate on average. A prior developed analytical method for determining feed and product concentrations in fermentation broth …
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Graduate Theses and Dissertations
Growing population and climate change inevitably requires longstanding dependency on sustainable sources of energy that are conducive to ecological balance, economies of scale and reduction of waste heat. Plasmonic-photonic systems are at the forefront of offering a promising path towards efficient light harvesting for enhanced optoelectronics, sensing, and chemical separations. Two-dimensional (2-D) metamaterial arrays of plasmonic nanoparticles arranged in polymer lattices developed herein support thermoplasmonic heating at off-resonances (near infrared, NIR) in addition to regular plasmonic resonances (visible), which extends their applicability compared to random dispersions. Especially, thermal responses of 2-D arrays at coupled lattice resonance (CLR) wavelengths were comparable …
A Proposed Process And Economic Analysis For A Manufacturing Facility For Nylon 6,6, Perry Doles
A Proposed Process And Economic Analysis For A Manufacturing Facility For Nylon 6,6, Perry Doles
Chemical Engineering Undergraduate Honors Theses
The global nylon market is a multi-billion-dollar industry that has been thriving in recent years due to advances in the process technology and its flexibility as a material. Nylon 6,6 is a versatile material with uses in many industries because of its ability manipulated into many forms. It is commonly used in applications that require heat resistance, chemical resistance, and high mechanical strength. It is commonly used in luggage, car parts, carpets, and many other plastic products that require the properties that nylon 6,6 exhibits. The versatility and demand for nylon 6,6 make it an attractive process for many potential …
Limits Of Small Scale Pressure Swing Adsorption, Aaron A. Moran
Limits Of Small Scale Pressure Swing Adsorption, Aaron A. Moran
ETD Archive
Portable or small scale pressure swing adsorption (PSA) systems have gained increasing popularity in both industry and literature due to the commercial success of personal oxygen concentrators (POCs). While these processes have much in common with larger PSA systems, significant differences exist that make understanding process limitations difficult. These include faster cycle times, smaller adsorbent particles, and a reduced column size. Macropore diffusion is traditionally assumed to control the mass transfer rate in columns packed with zeolite particles in an oxygen production process. While numerous studies have confirmed this assumption for the particle size used in industrial size PSA processes, …
Spurious Grain Formation During Directional Solidification In Microgravity, Supriya Ramashankar Upadhyay
Spurious Grain Formation During Directional Solidification In Microgravity, Supriya Ramashankar Upadhyay
ETD Archive
This research is aimed at carrying out a systematic investigation of the nucleation, and growth of spurious “misoriented” grains during directional solidification in the low gravity environment of space. Three Al–7 wt. % Si alloy cylindrical samples (MICAST-6, MICAST-7 and MICAST2-12) were directionally solidified on the Space Station at growth speeds varying from 5 to 50 µms-1 under thermal gradients varying from 14 to 33 K cm-1 in alumina crucibles, under a joint NASA-ESA (European Space Agency) project called, MICAST (Microstructure formation in casting of technical alloys under a diffusive and magnetically controlled convection conditions). The primary purpose of directionally …
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
ETD Archive
The U.S Environmental Protection Agency (EPA) launched the Transform Tox Testing Challenge in 2016 with the goal of developing practical methods that can be integrated into conventional high-throughput screening (HTS) assays to better predict the toxicity of parent compounds and their metabolites in vivo. In response to this need and to retrofit existing HTS assays for assessing metabolism-induced toxicity of compounds, we have developed a 384-pillar plate that is complementary to traditional 384-well plates and ideally suited for culturing human cells in three dimensions (3D) at a microscale. Briefly, human embryonic kidney (HEK) 293 cells in a mixture of alginate …
Treatment Of Dye Wastewater Using Dehydrated Peanut Hull, Nikitha Shamirpet
Treatment Of Dye Wastewater Using Dehydrated Peanut Hull, Nikitha Shamirpet
ETD Archive
The release of dye waste water into environment causes harm to aquatic life when they reach drains or other water sources. They pollute the soil and causes change in cycles of plant and animal life through bio-accumulation and nutrient cycle. Dyes which form residue or precipitate causes mutations or changes in the DNA of living organisms in and around the area of release of the dye into atmosphere. In this thesis, several runs were attempted to treat the synthetically prepared dye waste water using dehydrated peanut hull. The initial dye waste water samples were all collected and checked for absorbance, …
Effect Of History On The Binary Adsorption Equilibria Of Aluminium Terephthalate (Mil-53(Al)), Ufuoma Israel Kara
Effect Of History On The Binary Adsorption Equilibria Of Aluminium Terephthalate (Mil-53(Al)), Ufuoma Israel Kara
ETD Archive
Metal organic frameworks (MOFs) are highly porous solids with potential applications in a wide range of fields including gas separations and catalysis. Most of porous solids used in these applications such as zeolites and activated carbon usually have rigid structures. In contrast, a number of metal-organic frameworks (MOFs) exhibit structural transformation in response to external stimuli. Such materials show promise for applications such as sensors, actuators and adsorptive separations. Several thermodynamic formalisms were proposed in literature to explain this phenomenon, often known as gate-opening or “breathing” of the MOF material. In this study, the adsorptive behavior of MIL-53(Al), a MOF …
Determination Of Growth Kinetics, Yield Coefficients And Biodiesel Properties For The Green Microalgae Scenedesmus Dimorphus In Freshwater And Saline Medias, Morgan L. Cohara
Determination Of Growth Kinetics, Yield Coefficients And Biodiesel Properties For The Green Microalgae Scenedesmus Dimorphus In Freshwater And Saline Medias, Morgan L. Cohara
ETD Archive
Of the many alternative resources capable of generating biofuel, microalgal oil serves as a promising feedstock. Unfortunately, biodiesel production from microalgae is currently hindered by high operational costs. One primary causes for these high costs is the large quantity of freshwater required for cultivation. This experiment was designed to assess the feasibility of growing the green, freshwater microalgae Scenedesmus dimorphus in an increasingly saline environment. Both average yield coefficients and growth rates were monitored with increasing salt concentration. Determination of average yield coefficients allows for process scale-up and the optimization of production costs by minimizing raw material waste. Salinity was …
Kinetics And Ensemble Dynamics Of Colloidal Ellipsoids Near An Ac Electrode, Jiarui Yan
Kinetics And Ensemble Dynamics Of Colloidal Ellipsoids Near An Ac Electrode, Jiarui Yan
ETD Archive
The manipulation of colloidal particles via applying electric fields has been studied over the past 30 years due to the unique properties associated with the fabricated colloidal crystals. Most works in this field focused on utilizing an alternating current (AC) electric field with spherical particles. However, utilizing spherical colloidal particles as building blocks for complex microstructures has been challenging. Consequently, more recent work has shifted to employing complex colloids (anisotropic in nature) as building blocks for advanced materials. In our work, the phase diagram and the kinetics of assembling colloidal polystyrene ellipsoids under an AC electric field at low frequencies …
Influence Of Natural Convection During Dendritic Array Growth Of Metal Alloys (Gradient Freeze Directional Solidification), Suyog N. Mahajan
Influence Of Natural Convection During Dendritic Array Growth Of Metal Alloys (Gradient Freeze Directional Solidification), Suyog N. Mahajan
ETD Archive
Purpose of this study was to examine the microstructural evolution of primary dendrites during Gradient Freeze Directional Solidification process in cylindrical Pb-5.8% Sb alloy samples to generate the ground- based research data to support a future microgravity experiment on the Space Station in a convection free environment. Pb-5.8Sb was selected for this study because of its ease of processing and availability of physical property data which will be required for predicting the dendrite morphology parameters, such as, primary dendrite spacing and dendrite trunk diameter. This alloy is also susceptible to thermosolutal convection caused by density inversion of the met in …
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
ETD Archive
Hepatocellular carcinoma (HCC) is an invasive and aggressive cancer of the liver that arises due to chronic cirrhosis. Research into understanding HCC has focused on two-dimensional (2D) and three-dimensional (3D) technologies to simulate the liver microenvironment and use animal models to model how HCC affects the rest of the body. 3D hydrogel models are desired because they can mimic the transport behavior observed in vivo by structurally mimicking the extracellular matrix (ECM) without the ethical concerns of animal models. However, hydrogels can be toxic to cells and require optimal procedures for appropriate handling. In this study, we created 3D models …
Current State Of The Assets In The Chemical Engineering Laboratory At Rose-Hulman Institute Of Technology And Their Use In The Undergraduate Laboratory Course Sequence, Matthew Adams
Graduate Theses - Chemical Engineering
The Chemical Engineering Laboratory, also referred to as the Unit Operations (UO) Laboratory, is integral to any undergraduate Chemical Engineering curriculum as it provides students with the opportunity to gain practical and hands-on experience with processes that are commonplace throughout industry. The Chemical Engineering Department at Rose-Hulman Institute of Technology prides itself in providing its students with a practical education that will allow for an easy transition into industry as well as continued success throughout the students’ careers; as such, the assets in the Chemical Engineering Laboratory space and their use are paramount to this objective. The Chemical Engineering Department …
Beer, Booze, And Biofuels: An Introduction To Chemical Engineering, Kayla Revelle, Jacob Lambert, Kelly Kopchak
Beer, Booze, And Biofuels: An Introduction To Chemical Engineering, Kayla Revelle, Jacob Lambert, Kelly Kopchak
Senior Theses
The goal of this thesis project was to provide the layout, curriculum, and scheduling for an introductory course regarding chemical engineering for non-majors. Throughout the course of our studies in chemical engineering and engineering in general it had come to our attention that there were many myths regarding the classes and curriculum. We had heard countless times things such as “I am glad I’m not an engineering major”, “those classes seem so hard and boring”, or “It’s all math”. The purpose of this project and class was to dispel those myths and show non-majors what chemical engineering is all about. …
Pure And Binary Adsorption Equilibrium Of Nitrogen And Oxygen In Lilsx Zeolite, Himabindu Gandra
Pure And Binary Adsorption Equilibrium Of Nitrogen And Oxygen In Lilsx Zeolite, Himabindu Gandra
ETD Archive
Chemical products are made by combination of processes that includes synthesis, separation and purification. Separation processes comprises a large portion in these industries and are considered to be critical as most of the applications in chemical industries involves mixtures. Traditional separation methods such as distillation, evaporation, drying etc., requires high energy. For example, air separation to produce nitrogen and oxygen was previously practiced by cryogenic distillation that involves high pressure units and large energy requirement. On other hand, adsorption processes utilize less energy resources and is unique among separation methods. The phase separation is achieved by the existence of a …
Evaluation Of Mass Transfer Rate In Column Of Small Lilsx Particles, Mihikumar S. Patel
Evaluation Of Mass Transfer Rate In Column Of Small Lilsx Particles, Mihikumar S. Patel
ETD Archive
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 …
Effect Of Convection Associated With Cross-Section Change During Directional Solidification Of Binary Alloys On Dendritic Array Morphology And Macrosegregation, Masoud Ghods
ETD Archive
This dissertation explores the role of different types of convection on macrosegregation and on dendritic array morphology of two aluminum alloys directionally solidified through cylindrical graphite molds having both cross-section decrease and increase. Al- 19 wt. % Cu and Al-7 wt. % Si alloys were directionally solidified at two growth speed of 10 and 29.1 µm s-1 and examined for longitudinal and radial macrosegregation, and for primary dendrite spacing and dendrite trunk diameter.
Directional solidification of these alloys through constant cross-section showed clustering of primary dendrites and parabolic-shaped radial macrosegregation profile, indicative of “steepling convection” in the mushy-zone. The degree …