Engineering Commons^™

An Investigation Of Strong Electrostatic Adsorption Using Formed Commercial Supports, Connor Brendan Mcdonough

Theses and Dissertations

Strong electrostatic adsorption (SEA) is a well-tested procedure for the synthesis of supported monometallic and bimetallic nanoparticles with ultrasmall size (< 2 nm). Where, previous studies have laid the foundation for SEA using a variety of powdered supports, catalysts in this form are not suited for large volume chemical applications where pressure drop is critical to the process economics. Although there is no fundamental difference between the surface functional groups on powdered and extruded supports, the present study examined electrostatic adsorption as it relates to proton diffusion, precursor diffusion, and capillary imbibition.

Three formed alumina spheres and one carbon extrudate were selected for study. The alumina spheres, provided by BASF, were developmental materials with varying pore size distributions between 12 and 24800 angstroms. The carbon, provided by ADM and manufactured by CABOT, was strictly microporous in structure and was included to investigate the differences in mass transport as a function of support material.

Results indicated, a significant limitation in the approach to pH equilibrium comparing formed alumina spheres with the same …

Printing Quality Improvement For Laser-Induced Forward Transfer Bioprinting: Numerical Modeling And Experimental Validation, Jie Qu, Chaoran Dou, Ben Xu, Jianzhi Li, Zhonghao Rao, Andrew Tsin

Manufacturing & Industrial Engineering Faculty Publications

Laser-induced-forward-transfer (LIFT)-based laser assisted bioprinting (LAB) has great advantages over other three-dimensional (3D) bioprinting techniques, such as none-contact, free of clogging, high precision, and good compatibility. In a typical LIFT based LAB process, a jet flow transfers the bioink from the ribbon to the substrate due to bioink bubble generation and collapse, and the printing quality is highly dependent on the jet flow regime (stable or unstable), so it is a great challenge to understand the connection between the jet flow and the printing outcomes. To tackle this challenge, a novel computational-fluid-dynamics (CFD)-based model was developed in this study to …

An Analysis Of The Factors Affecting Attitudes Toward Drone Delivery And The Moderating Effect Of Covid-19, Jeremy A. Frazier

Doctoral Dissertations and Master's Theses

This research explored the factors affecting attitudes toward drone delivery and the moderating effect of COVID-19. Government effort to address the COVID-19 pandemic has led to social distancing and shelter-in-place guidelines. Many states have imposed additional regulations, restricting retailers from offering in-store shopping and restaurants from offering indoor dining. As a result, the use of delivery services has increased. In a further effort to reduce virus spread, some delivery services now offer a contact-free option. The contact-free option permits orders to be left at a designated location, eliminating the physical-human interaction upon delivery. The contact-free nature and potential speed of …

Additively Manufactured Dielectric Elastomer Actuators: Development And Performance Enhancement, Stanislav Sikulskyi

Doctoral Dissertations and Master's Theses

The recently emerging and actively growing areas of soft robotics and morphing structures promise endless opportunities in a wide range of engineering fields, including biomedical, industrial, and aerospace. Soft actuators and sensors are essential components of any soft robot or morphing structure. Among the utilized materials, dielectric elastomers (DEs) are intrinsically compliant, high energy density polymers with fast and reversible electromechanical response. Additionally, the electrically driven work principle allows DEs to be distributed in a desired fashion and function locally with minimum interference. Thus, a great effort is being made towards utilizing additive manufacturing (AM) technologies to fully realize the …

Developing A Lab-Scale Fluidized Bed Dryer System To Enhance Rough Rice Drying Process, Kaushik Luthra

Graduate Theses and Dissertations

For more than half of the world's population, rice (Oryza sativa L.) is a staple meal. However, rice growers encounter difficulties supplying this demand, particularly in developing nations, where rice is susceptible to spoilage if the moisture content is not lowered to a safe level soon after harvest. As a result, traditional drying methods, such as sun drying and natural air drying, are commonly used by rice growers, particularly in underdeveloped nations. However, these procedures are time-consuming and can lead to rice spoilage. On the other hand, fluidized bed drying is a well-established technology that might give rice growers a …

Synthesis And Performance Testing Of Ecm Fiber Scaffolds, Cassandra Reed

Graduate Theses and Dissertations

The progression of regenerative medicine has advanced the treatment of multiple illnesses and injuries throughout the years. A good example of the benefits of this research is the work that has gone into volumetric muscle loss (VML), where more than 20% of the muscle is loss. Skeletal muscle makes up 40% of the human body so a loss of that size greatly diminishes the strength, the flexibility, physiology, and quality of life of the injured individual. For that reason, various techniques are used to counteract the loss of structure and innate cellular signaling in order to circumvent that from happening. …

A Portable Point-Of-Care Device Using Joule Heating And Latent Energy Storage For The Temperature Regulation Of Isothermal Nucleic Acid Amplification Tests, Aubrey Lynn Schultz

Graduate Theses and Dissertations

Accurate and early diagnosis of infectious diseases extremely important. Rapid diagnosis allows for effective treatment and increases the chance for recovery without complications. Additionally, the ability to test the populace frequently, swiftly, and affordably significantly aids in containing wide-scale outbreaks. In terms of specificity and sensitivity, nucleic acid amplification tests (NAAT) are one of the best options for diagnosing infectious diseases. Isothermal NAATS present a unique opportunity to create diagnostic tests deployed at a Point-of-Care (POC) level. Specifically, loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA) have the potential to deliver reliable POC diagnostics in low-resource settings. When designing …

Privacy-Preserving Cloud-Assisted Data Analytics, Wei Bao

Graduate Theses and Dissertations

Nowadays industries are collecting a massive and exponentially growing amount of data that can be utilized to extract useful insights for improving various aspects of our life. Data analytics (e.g., via the use of machine learning) has been extensively applied to make important decisions in various real world applications. However, it is challenging for resource-limited clients to analyze their data in an efficient way when its scale is large. Additionally, the data resources are increasingly distributed among different owners. Nonetheless, users' data may contain private information that needs to be protected.

Cloud computing has become more and more popular in …

Electrochemical Deposition In Energy Storage Devices, Witness Atutala Martin

Graduate Theses and Dissertations

Metals, whether in a solid or soluble ion form, are a vital part of any electrochemical storage system. More so, Li metal is widely considered as the ideal anode because of its low density and low electrochemical potential (-3.04 V vs. the standard hydrogen electrode – SHE). However, just like most metals, it does not plate or strip evenly during cycling which can lead to cycling performance issues, short cycling lifespans, and even safety concerns brought about by dendrites that can cause internal short-circuiting within cells. This research focused on investigating the electroplating of metals in both aqueous and non-aqueous …

Decoupling The Effects Of Interfacial Chemistry And Grain Size In Perovskite Stability, Mirra M. Rasmussen, Kyle M. Crowley, Miranda S. Gottlieb, Geneviève Sauvé, Ina T. Martin

Student Scholarship

No abstract provided.

Surface Energy And Microstructure: The Effect Of The Underlying Substrate On Perovskite Film Formation For Solar Cell Absorbers, Mirra M. Rasmussen, Kyle M. Crowley, Ina T. Martin

Student Scholarship

No abstract provided.

Towards Intelligent Structural Health Monitoring Of Infrastructure Systems: An Interdisciplinary Study Of Acoustic Emission Monitoring, Numerical Simulation, And Artificial Intelligence, Li Ai

Theses and Dissertations

Some complex infrastructure systems, such as nuclear facilities and bridges, are subject to structural damage due to environmental erosion, material deterioration, and other factors after long periods of use. Stress corrosion cracking (SCC) and alkali-silica reaction (ASR) have been identified as the primary degradation mechanisms for steel and concrete structures in nuclear facilities and bridges. Ensuring the integrity and operational safety of structures during their lifetime is an important task. Nondestructive methods and structural health monitoring can be used to detect damage caused by SCC and ASR instead of conventional visual inspection. Among the nondestructive methods, acoustic emission (AE) is …

Regulation Of Inflammatory Processes By Tryptamine, Cannabidiol And 2,3,7,8-Tetrachlorodibenzo-P-Dioxin, Nicholas Dopkins

Theses and Dissertations

Host immunity is a complicated system of pro-inflammatory and anti-inflammatory processes that respond to exogenous and endogenous threats to regulate host physiology, inhibit carcinogenesis, and protect from infections. Sustained deviance from normal immunological function occurs due to a variety of factors both endogenous and exogenous, with some factors that can dysregulate host immunity including: genetics, microbiota composition, toxin exposure, age, gender, and smoking. The etiology of inflammatory disorders is both convoluted and complex due to the sheer number of facets regulating host immunity. To better contribute to understanding how immunological dysregulation occurs we focused on how three anti-inflammatory compounds (tryptamine, …

A Multi Physics Integrated Solution For A High-Pressure Stage Turbine Efficiency And Durability, Sanjay Chopra

Theses and Dissertations

World electricity demand is projected to grow at an annual rate of ~ 2.1% to year 2040₁. EIA projects nearly 50% increase in world energy usage by 2050 led by growth in Asia.[28];[29]. It is predicted that the global electricity demand grows at approximately 1.6 % per year from approximately 2008 and forecasted to approximately 2035, twice the rate of primary energy demand. This raises electricity's usage in total final energy consumption from approximately 19% in 2018 to approximately 24% in 2040. Electricity demand growth is set to be particularly strong in developing economies. .[28];[29];[38] As an enabler, to meet …

Effects Of Overmolding Process Parameters On Bondzone Quality, Vivek Varma Penumetsa

Theses and Dissertations

Urban air mobility (UAM) vehicles refer to small sized systems that transport people or cargo by air. In recent years, the interest in UAM vehicles has risen to combat traffic congestion, provide faster delivery times, or provide easier access to remote places. To meet potential future demand, traditional aircraft manufacturers must introduce manufacturing technologies that can cope with high production rates. One manufacturing technology aircraft manufacturers are investigating is overmolding, a manufacturing technology common to the automotive industry. Overmolding combines the manufacturing and assembly cycles into one by injection molding a component on top of a substrate. The quality of …

An In Vitro Approach To Vascular Therapeutic Testing, Shahd Ali Hasanain

Theses and Dissertations

Aortopathies refer to a broad class of pathological conditions affecting the aorta and are a major cause of morbidity and mortality in the US. Specifically, aortic aneurysms and aortic dissections have diverse etiologies that are initiated by alterations in the tissue’s extracellular-matrix (ECM) proteins, namely collagen and elastin, thereby predisposing the aortic wall to weaken and rupture. Pentagalloyl glucose (PGG) has recently emerged as a non-surgical treatment to reduce the risk of dissection or rupture. PGG is a known antioxidant and anti-inflammatory which has been shown to have ECM-restorative qualities that enhance collagen and elastin’s functional properties. Prior studies using …

Robust Adaptive Model Predictive Control Of Nonlinear Sample-Data Systems, Lixing Yang

Theses and Dissertations

In the past decades, model predictive control (MPC) has been widely used as an efficient tool in areas such as process control, power grids, transportation systems, and manufacturing. It provides an approach that aims to design stabilizing feedback to the system so that the performance criterion gets minimized while the state and input constraints get satisfied. In many situations, MPC may outperform other approaches to design and implement feedback control systems. Furthermore, MPC may solve optimization problems with large and practically important sets of multiple-input multiple-output (MIMO) systems efficiently. A typical implementation of MPC predicts the optimal control inputs that …

Reduced Order Modeling Based On Hybrid Snapshot Simulation, Feng Bai

Theses and Dissertations

Reduced order model (ROM) is an emerging technique for rapid and efficient numerical simulation and computation in science and engineering applications. The ROM consists of two stages: (1) the offline snapshot simulation to produce high-quality snapshot data representative of model trajectories, from which the projection subspace can be extracted and used for ROM construction; and (2) the online simulation to utilize the ROM built in stage 1. The snapshot simulation is traditionally performed with full order model (FOM) and is computationally demanding, which is one of the most critical limiting factors for the development and deployment of ROM in real-world …

Heterogeneous Extended Langmuir Model With A Truncated Multi-Normal Energy Distribution For Fitting Unary Data And Predicting Mixed-Gas Adsorption Equilibria, Sofia Tosso

Theses and Dissertations

A heterogeneous extended Langmuir model (HEL) that uses a truncated frequency energy distribution based on a one, two or three normal distributions is presented to predict gas adsorption mixtures of single, binary, and ternary gas experimental data involving CO2, H2S and C3H8 on H-modernite reported in the work of Ritter et al (1986) in terms of both solid phase molar fractions and total loadings. These models were initially fitted against single gas data and then used to predict binary data and to establish the type of perfect correlations, whether positive or negative, exist amongst these three species. The models then …

Optimizing Heat Pipes With Partially-Hybrid Mesh-Groove Wicking Structures And Its Capillary-Flowing Analysis By Simulation, Guanghan Huang

Theses and Dissertations

Heat pipes are known as efficient two-phase heat transfer devices and widely utilized in thermal management of power plants and electronics. The hybrid mesh-groove wick promises to attain a higher thermal performance of the heat pipe by balancing the permeability and capillarity. However, traditional fully hybrid mesh-groove wick presents considerable condensation thermal resistance due to the condensed quiescent working fluid and thick, saturated wick.

In this study, a novel partially hybrid mesh-groove wick has been proposed to enhance the evaporation of L-shaped copper-ethanol heat pipes. L-shaped heat pipe promotes high-efficient draining of condensed liquid by gravity, while traditional straight-shaped heat …

Jme 4110: Lego-Lock Block, Diana Engelhardt, Dmitriy Kornyukhov, Chelsea Borders

Washington University / UMSL Mechanical Engineering Design Project JME 4110

Design a building block device that assembles similarly to a LEGO brick, but also has the capability to lock an assembly state between two bricks. Scale (size) not critical for this proof of concept (standard LEGO blocks may be too small for this first attempt).

Jme 4110: Drag Line Wind Energy Generator, David Gengenbacher, Mouhamadou Bamba Kane, Brian Bakula

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The goal of this project was to develop a prototype capable of power a 10 watt light bulb using only the energy from wind.

Jme 4110: Extended Hole Punch, Lucas Mennemeier, Jason Zobrist

Washington University / UMSL Mechanical Engineering Design Project JME 4110

DESIGN AND DEVELOP A WORKING PROTOTYPE OF A SINGLE-HAND, SINGLE-HOLE PUNCH WITH AN EXTENDED THROAT THAT WILL BE ABLE TO REACH FURTHER INTO A SHEET OF PAPER THAN A STANDARD SINGLE-HOLE PUNCH. THIS CAN BE A PUNCH ATTACHMENT OR A STAND-ALONE DEVICE. EITHER DESIGN CHOSEN WILL ALSO BE ABLE TO BE CONVERTED INTO AN EMBOSSING TOOL FOR EMBOSSING SEALS INTO DOCUMENTS

Jme 4110: Data Cooling Center, Christopher Schmidt, Brennan Fogarty, Suruchi Aryal

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The group will design a way to efficiently move heat within a framework of using dielectric fluid as a heat transfer medium. The heat will be removed from a data center or a simulated data center. The group will evaluate the best possible design with the understanding that cooling data centers generate a large amount of heat. The design will also be constructed in such a manner that it can be scaled up to a larger size. Dielectric fluid will be used due to its efficiency compared to that of an air cooled system or a compressed refrigerant system. Account …

Jme 4110: Water Reservoir Energy Storage, Kristen Grace, Supapan Thammanok, Leticia Zoratto Lunge

Washington University / UMSL Mechanical Engineering Design Project JME 4110

The goal of this project was to create a demonstrative model of a Pumped Hydroelectric Storage System (PHS). A PHS stores energy by draining water from an upper reservoir through a turbine to generate electricity. This water is then pumped from a lower reservoir to the original upper reservoir to restart the system cycle. Using existing PHS applications, a small-scale prototype was built using an aquarium pump and mini turbine, along with PVC and plastic containers. When water is run through the system, a multimeter can be used to show the power output of the system. In addition to functionality, …

Jme 4110: Vibratory Parts Feeder, Adin Stambolic, Patrick Edward Vastola, Noah Herrin

Washington University / UMSL Mechanical Engineering Design Project JME 4110

Design an inexpensive, modular and tunable vibratory feeder to move different size particles from one place to another. The feeder can change according to the shape and size of the particles while in use.

Jme 4110: Mass Production Of Multi-Sphere Approximated Parts, Christopher Hartley, Chad Gorski, Matthew Brady

Washington University / UMSL Mechanical Engineering Design Project JME 4110

For this project, the team needs to design a mass production manufacturing process. The product of the process will be parts that represent, as closely as possible, approximations of parts developed using Discrete Element Modelling (DEM) software. Since the software uses spheres to efficiently model complex parts, the manufacturing process must also utilize spheres as the building blocks for the approximated parts. As a proof of concept, this project uses river pebbles as the parts being approximated by the software and modeled by the multi-sphere production process.

Near-Shore Sediment Transport Under Cnoidal Waves Using Particle Image Velocimetry, Jenna Rose Katrina

Theses and Dissertations

With future trends showing a higher percentage of the human population living along the coast, coastal resilience is a significant topic of concern for many researchers. The purpose of this research was to analyze near-shore sediment transport under different wave parameters using the technique of Particle Image Velocimetry (PIV) and laboratory studies for linear and nonlinear cnoidal waves. At the deeper extent of the nearshore profile, waves will tend to be linear, having an Ursell number less than 40, with little or no net sediment transport due to orbital velocities. The velocities are the same under the crest and trough …

Visualizing Publication Trends In Webology Journal: A Bibliometric Review Based On The Scopus Database (2006-2020), Ayush Kumar Patel, Madan Singh, Kunwar Singh, Avadhesh Kumar Patel, Akhilesh Kumar Varma, Ramesh Kuri

Library Philosophy and Practice (e-journal)

This study aims to explore the publication trends in Webology Journal. The Scopus database was chosen for the extraction of bibliographic data for the period 2006 to 2020. Then, VOSviewer software was used to analyse the data and generate visualization network maps. A total of 295 publications were found during the study period. The various bibliometrics indicators have been applied to identify the publication trends of Webology Journal. The finding revealed that the highest number of papers (92) and the maximum number of citations (273) appeared in 2020. Among the most contributing nations, Iran has contributed 63 documents, followed by …

Reduced Sample Minimum Strength Estimates For Novel Material Systems: Effects On Confidence And Structural Risk, Andrew Carl Ollikainen

Theses and Dissertations

There are ongoing efforts to standardize the materials, methods and process controls used in additive manufacturing. To support the broader use of additive manufacturing (AM) in the aerospace industry, the statistics working group of the Composite Materials Handbook (CMH-17) is evaluating whether its current methods of calculating minimum strength values are suitable for these new materials. The work presented in this dissertation investigates methods for determining minimum strength estimates in a way that will benefit application of AM materials in engineering practice. The greatest challenge in conducting such an assessment is accounting for the many variables in material, processing, and …