Engineering Commons^™

Cancer Treatment By Targeting Hdac4 Translocation Induced By Microsecond Pulsed Electric Field Exposure: Mechanistic Insights Through Kinases And Phosphatases, Zahra Safaei

Theses and Dissertations

Epigenetic modifications, arising from sub-cellular shifts in histone deacetylase (HDAC) activity and localization, present promising strategies for diverse cancer treatments. HDACs, enzymes responsible for post-translational histone modifications, induce these epigenetic changes by removing acetyl groups from ε-N-acetyl-lysine residues on histones, thereby suppressing gene transcription. Within the HDAC group, class IIa HDACs are notable for their responsiveness to extracellular signals, bridging the gap between external stimuli, plasma membrane, and genome through nuclear-cytoplasmic translocation. This localization offers two significant mechanisms for cancer treatment: nuclear accumulation of HDACs represses oncogenic transcription factors, such as myocyte-specific enhancer factor 2C (MEF2C), triggering various cell death …

Development Of A Xenograft For Annular Repair Using Pulsed Electric Field Exposures For Enhanced Decellularization, Prince Mensah Kwaku Atsu

Theses and Dissertations

Severe back injuries and chronic pain necessitate surgical replacement of damaged intervertebral disc (IVD) cartilage in advanced disease stages. Bovine IVD tissue has been exposed to an upper threshold pulsed electric field (PEF) dose, causing cell death without thermal damage to the tissue. Subsequent PEF exposures at lower magnitudes have accelerated the removal of immunogenic biomolecules though electrokinetic extraction using optimized aqueous solutions. This approach yields a natural scaffold, ready for biocompatibility and mechanical strength assessment. The effects of microsecond pulsed electric fields (µsPEF) on primary bovine AF fibroblast-like cells have been characterized in vitro. PEFs of 10 and 100 …

Integrated Computer-Aided Design, Experimentation, And Optimization Approach For Perovskites And Petroleum Packaging Processes, Swapana Subbarao Jerpoth

Theses and Dissertations

According to the World Economic Forum report, the U.S. currently has an energy efficiency of just 30%, thus illustrating the potential scope and need for efficiency enhancement and waste minimization. In the U.S. energy sector, petroleum and solar energy are the two key pillars that have the potential to create research opportunities for transition to a cleaner, greener, and sustainable future. In this research endeavor, the focus is on two pivotal areas: (i) Computer-aided perovskite solar cell synthesis; and (ii) Optimization of flow processes through multiproduct petroleum pipelines. In the area of perovskite synthesis, the emphasis is on the enhancement …

A Systems Approach To Process Design And Sustainability - Synergy Via Pollution Prevention, Control, And Source Reduction, Emmanuel Apau Aboagye

Theses and Dissertations

Historically, process design prioritized efficiency and profitability, often overlooking environmental and societal implications. However, given the global challenges like climate change and resource scarcity, there is a growing emphasis on embedding sustainability into process design. Adopting a systems-oriented approach provides a comprehensive view, spanning from raw material acquisition to end-of-life product management. Such an approach not only identifies potential sustainability challenges but ensures that solutions foster both environmental responsibility and economic viability. In this study, a comprehensive framework for designing industrial systems is introduced, aiming to encompass the entire lifecycle impacts of chemical processes. The research initially delves into two …

Optimal Control Of Ion Exchange Process For Chromate Removal And Protein A Chromatography For Antibody Extraction, Fadi Ghanem

Theses and Dissertations

Ion exchange resins are widely used in the extraction of hazardous chemicals as well as the recovery of precious molecules. Therefore, an early breakthrough from the resin system can lead to toxic compounds affecting the drinking water quality or inefficient use of costly resins. Hence, accurate modeling of the ion exchange process and control strategy can enable decisions that assist in avoiding leakage when facing fluctuations in the inlet contaminant concentrations. In this work, the ion exchange process is modeled via the method of moments where the system uncertainties are captured via stochastic modeling using Ito processes. The flow rate …

Investigation Of The Performance Of Anti-Corrosive Coating Materials Derived From Bio-Based Feedstocks, Sarah Anne Salazar

Theses and Dissertations

Corrosion is a costly phenomenon that is largely responsible for the deterioration of various infrastructures. While there are many corrosion prevention techniques, polymeric coatings are the most cost-effective and frequently used methods for protection of metal surfaces. The most commonly employed polymeric coatings are non-renewable BPA-based epoxide resins. Common curing agents are also the derivatives of hazardous amines such as ethylene di-amine and methylene dianiline. Therefore, there is a growing demand to develop renewable and less-harmful precursors from biomass to replace rapidly depleting petrochemicals. This thesis focuses on the characterization and optimization of anti-corrosive polymeric coating formulations derived from renewable …

Exploring Senior Chemical Engineering Students’ Approach To Process Safety Decision Making, Jeffrey Saunders Stransky

Theses and Dissertations

Despite investments in chemical process safety education, evidence suggests that engineers’ decision making may contribute to process safety incidents. Currently, limited educational endeavors in process safety decision making exist, raising the need for a better understanding of how to prepare chemical engineering students for industry decisions. This dissertation fortifies current process safety education through three studies involving senior chemical engineering students. Study One developed the Engineering Process Safety Research Instrument (EPSRI) through exploratory and confirmatory factor analyses. Educators may use the EPSRI to evaluate their students’ moral development. Study Two evaluated a digital process safety game, Contents Under Pressure, on …

Enhancing Sustainable Process Designs Through Strategic Material Utilization And Waste Minimization Approaches, John David Chea

Theses and Dissertations

Sustainability is a growing concern as resources are continually depleted for various applications without adequate renewal plans. The resulting impacts on the ecosystem, health, and resource circularity are often overlooked. This research analyzes improvement opportunities at each major stage in a product's life cycle. Raw material acquisition, product synthesis, process waste management, and the fate of a material in the end-of-life phases were examined. The viability of utilizing renewable resources has been demonstrated in this work by extracting bio-based chemicals from underutilized renewable resources at a commercial scale and transforming the extracted resources into polymeric materials. The optimization of raw …

Towards Environmentally Sustainable, High-Performance, Lightweight Composites For Automotive Applications, Jasmin Zamudio Vasquez

Theses and Dissertations

The increasing public demand in the world automotive industry to improve the environmental sustainability of their manufactured vehicles without sacrificing drivers' comfort and safety and the high cost of lightweight materials have driven researchers to reconsider materials used in the automotive application. Thus, this work aims toward the production of environmentally sustainable, high-performance, lightweight composites, utilizing recycled carbon fibers (RCFs) and pyrolyzed tire particles (PTPs) reclaimed from pyro-gasification of CFRP wastes and end-of-life tires (ELTs), respectively, as reinforcements for cardanol-based epoxy resins. The fabricated composites exhibited rubbery-like behavior at 25 °C. Spectroscopic, rheological, physical, thermal, thermomechanical, and mechanical characterizations were …

Bio-Ionic Liquid Functionalized Hydrogels Towards Smart Tissue Regeneration, Vaishali Krishnadoss

Theses and Dissertations

A blend of scaffolds, biologically active molecules, and cells are required to assemble functional constructs to repair and regenerate damaged tissue or organ via tissue engineering. The scaffold supports cell growth and proliferation and acts as a medium for diverse cellular activities. Even though hydrogel's high-water content and flexible nature make it a pronounced applicant as a scaffold, they exhibit significant technical limitations such as the absence of cell-binding motifs, lack of oxygen, conductivity, adhesive properties, growth of cells in a 3-dimensional (3D) microenvironment. In this thesis, a novel material platform is evaluated and studied to address the concerns mentioned …

Advancing The Development Of Additively Manufactured Sequentially Cured Interpenetrating Polymer Networks, Rachael J. Ross

Theses and Dissertations

Recently vat photopolymerization (VPP), a type of additive manufacturing (AM), has the potential to be used for a variety of commercial and military applications due to the ability to make custom parts rapidly and with complex geometries. Many commercially available photopolymerizable resins consist of (meth)acrylate and epoxy functionality to ensure rapid cure time and minimal shrinkage. Today, researchers continue to find the optimal balance of (meth)acrylate/epoxy functionality in unique formulations and network configurations, such as interpenetrating polymer networks (IPN)s, to enhance processibility and the quality of the final printed part. This work explores the structure-property relationships of a set of …

Centrifugal Assembly Of Bijel Ropes Via Helical Microfluidics, Shankar P. Kharal

Theses and Dissertations

Bicontinuous interfacially jammed emulsion gels (bijels) are soft materials that retain a liquid bicontinuous network stabilized by an interfacially jammed layer of nanoparticles. In this thesis, we investigated a microfluidic twisting method to fabricate micro-ropes of nano-structured bijel fibers. This method shows how weak microfibers with tensile strengths of a few kPa can be reinforced by 4 orders of magnitude by means of microfluidic twisting. Microfluidic twisting allows to produce continuous bijel fiber ropes of controllable architecture. Modelling the fluid flow field reveals the rope geometry dependence on a subtle force balance composed of rotational and translational shear stresses. However, …

Design Of A Custom Digital Light Projection Printer For In-Situ Production Of Composites With Improved Thermomechanical Properties, Margaret Anne Gillan

Theses and Dissertations

This work seeks to improve upon the existing state-of-the-art for vat photopolymerization additive manufacturing; namely, producing in-situ composites that combine the precision and high-performance materials of the vat photopolymerization with the strength of fiber-reinforced polymer composites. A custom-designed digital light projection printer was designed and built for printing composites, which includes an automated fiber tape system to place woven E-glass fiber mats in-situ. To validate the performance improvement of composites versus the neat matrix, composites were fabricated on the custom printer with hand-placed fiber mats. A high-performance, dual-cure resin was used for these studies. The effect of layer height on …

Integrating Vibratory Membrane-Based Water Recovery Systems For Sustainable Food And Beverage Production, Michael Vincent O. Laurio

Theses and Dissertations

A vibratory nanofiltration (NF) system was investigated for the preconcentration of coffee extracts for soluble coffee production. The simulated coffee extracts studied contained mostly suspended and colloidal organic components that, although were effectively rejected by the NF membrane (>99% turbidity rejection), affected the vibratory NF performance. The vibratory NF operation improved permeate flux, rejection efficiencies, and reduced flux decline from those observed in crossflow (CF) operation. Further, the effects of applied transmembrane pressure (TMP) and vibrational frequency (F) at corresponding displacement (d) were investigated and modeled. A semi-empirical resistance-in-series model was employed to characterize the mass transfer mechanism, osmotic …

Enhancement Of Electrospun Nanofiber Properties Via Automated Track Post-Draw Processing, David Anthony Brennan

Theses and Dissertations

Electrospinning is an alternative manufacturing method, capable of producing fibers with nanoscale diameters from a wide range of different polymers in a process which is relatively simple and inexpensive in comparison to other forms of nanofiber production. This has made electrospinning the subject a great deal of research as a method of producing nanofibers for various high-performance applications. However, electrospun nanofiber tensile strength is weak in comparison to conventional fibers of the same material, preventing widespread use and marketization. This disparity in mechanical strength is attributed to poor polymer chain alignment in individual fibers, caused by the absence of a …

Dewetting Induced Lipid Bilayer Multicomponent Scaffold For Synthetic Cell Vesicle And Their Stability, Anjana Khanal

Theses and Dissertations

This thesis introduces a microfluidic method to generate monodisperse water-in-oil-in water double emulsions. The microfluidic method is able to produce double emulsions with high degree of controllability and flexibility on size and number of droplets. We demonstrate this by producing double emulsions containing 1-8 inner water droplets and studied their dewetting phenomena to lipid bilayer scaffold. Our study shows that for the dewetting phenomenon to occur the oil must be volatile, polar and should make low contact angle with the involved interfaces. The chloroform shows self-emulsification behavior in presence of surfactant F127. The topological droplets formation with multiple compartments is …

Epoxy-Functional Thermoplastic Copolymers And Their Incorporation Into Thermosetting Resins, Kayla Rose Sweet

Theses and Dissertations

While polymers have secured a place in the consumer, industrial, and military markets over the last seventy years, the next generation of polymers must become more renewable, more adaptive, and higher performing to bridge industrial needs and environmental gaps. To this end, unique network configurations of copolymers and interpenetrating polymer networks (IPNs) have been employed to combine features of two or more polymers into a single material that surpasses the sum of its parts. The customization of polymer networks can be made possible via dual-functional monomers, molecules characterized by two different reactive substituents that allow for versatile methods of polymerization. …

Synthesis And Characterization Of Thermosetting Epoxy Resins From Lignin-Inspired Phenolics, Kelli Marie Hambleton

Theses and Dissertations

The need for renewable polymers able to replace their petrochemical counterparts continues to grow as sustainability concerns constantly rise. Bisguaiacol, a bio-based alternative to bisphenol-A, has been synthesized using vanillyl alcohol and guaiacol via an electrophilic aromatic condensation. Purification provides both bisguaiacol and an oligomeric coproduct with a consistent number average molecular weight and dispersity of about 650 Da and 1.00, respectively, across multiple reaction volume scales. This coproduct has been well characterized as a low molecular weight novolac averaging 5 hydroxyls per molecule and was transformed into an epoxy resin suitable for use in thermosetting resin development. By utilizing …

Bijels Made By Solvent Transfer Induced Phase Separation: Formation Principles And Transport, Stephen Boakye-Ansah

Theses and Dissertations

Bijels are made of non-equilibrium particle-stabilized emulsions with a bicontinuous arrangement of the constituent fluid phases. They spontaneously form through arrested spinodal decomposition in mixtures of partially miscible liquids and neutrally wetting colloidal particles. Soon after their discovery over 10 years ago, Prof. Mike Cates, Lucasian Professor of Mathematics, predicted their future use as continuously operated cross-flow reactors for chemical reactions between immiscible reactants.

Towards this goal, work in this thesis focuses on designing bijels via Solvent Transfer Induced Phase Separation (STrIPS) for microfluidic transport applications. Structure-function relationships of STrIPS bijels stabilized by silane functionalized nanoparticles are developed. In-situ surfactant …

Study And Characterization Of Conductive Elastomers For Biomedical Applications, Hadis Gharacheh

Theses and Dissertations

Health issues have always been one of humankind's biggest challenges. Over the last century, there has been significant and monumental progress in health and biomedical science, with the end goal of alleviating and eliminating illnesses and ailments. For developing biomedical devices, polymers and elastomers group among other types of biomaterials have been highlighted to be used due to high flexibility, stability, biocompatibility, and mechanical and rheological characteristics. In this work, the characterization of acrylated poly glycerol_sebacate (PGSA) polymer conjugated with bio ionic liquid (BIL) was investigated. Results showed high biocompatibility, high printability with tunable mechanical, adhesive, and conductivity properties. For …

Synthesis And Evaluation Of Catalytic Application Of Porous Resin, Mahboubeh Nabavinia

Theses and Dissertations

The abilities to tailor catalytic functional groups and chemical characteristics onto a robust polymer structure make mesoporous phenolic resins great candidates for catalytic support applications. The use of a template synthesis method for configuring a catalytic structure is neither commercially nor environmentally friendly. In this Ph.D. thesis, new one-pot template-free methods for synthesizing mesoporous metal-doped phenol-formaldehyderesin were developed. The methods facilitate scaling for industrial catalytic applications in pharmaceutical, environmental, and medical applications. Heterogeneous palladium centered catalytic mesoporous structures were synthesized by a single-stage template-free method. BET adsorption measurements, SEM, EDX, XPS, and TEM were used to study the surface area, …

Hybrid Monomers & Resins For High-Performance Thermosetting Polymers, Thermoplastics, & Additive Manufacturing, Alexander William Bassett

Theses and Dissertations

Vinyl ester and epoxy resins are used to produce thermosetting polymeric materials for a variety of commercial and military applications due to their relatively high moduli (2-3 GPa at 25 deg C), glass transition temperatures (Tgs) (greater than or equal to 120 deg C), and adequate fracture toughness (G1C approx. 200-250 J m-2). Most commercially available vinyl ester and epoxy resins are typically cured via traditional manufacturing techniques such as resin transfer molding and thermal curing. However, additive manufacturing (AM) has gained significant traction as a favorable manufacturing technique over traditional methods due to the ability to create customizable parts …

Fabrication Of Enhanced Carbon Based Biocompatible And Biodegradable Microelectronic Materials Derived From Lignocellulosic Biomass, Harrison Thomas Hawkins

Theses and Dissertations

The development of materials capable of harmlessly being broken down and removed from the body is a crucial step towards the development of short-term application electronic biomedical implants. Once developed, these implants, known as bioresorbable electronics, will open a wide array of temporary applications in the field of biomedical implantable devices. Necessary to the operation of bioresorbable electronics within the body is a power source that is similarly biocompatible and biodegradable. To this end, enhanced carbon-based materials and a bio-ionic liquid were developed for the fabrication of a preliminary implantable and bioresorbable battery and tested for functional properties. Electrodes were …

Bio-Based Thiol-Ene Polymer Electrolytes, Elyse Antonia Baroncini

Theses and Dissertations

Industrial and consumer demand for smaller and safer technologies motivates a global research effort to improve electrolytic polymer separators in lithium-ion batteries (LIBs). To incorporate the aromatic structural advantages of lignin, an abundant and renewable resource, into polymer electrolytes, molecules that can be derived from lignin are functionalized and UV-polymerized with multifunctional thiol monomers. Monomer aromaticity, thiol molecular weight, and total functionality are varied, allowing for analysis of the relationships between polymer structure and electrochemical properties.

The synthesized polymers display conductivities on the order of 10^-5 S/cm for gel polymer electrolytes and 10^-4 S/cm for solid polymer electrolytes, comparable to …

The Creation, Validation, And Implementation Of The Engineering Process Safety Research Instrument, Brittany Lynn Butler

Theses and Dissertations

The purpose of this study was to develop and validate an instrument that can measure how senior chemical engineering students make process safety decisions. The Engineering Process Safety Research Instrument (EPSRI) contains dilemmas that represent process safety scenarios, followed by three decision options, and 12-15 considerations that fall into pre-conventional, conventional, or post-conventional forms of reasoning. Three studies were completed as a part of this research. The content validation study ensured the dilemmas represented process safety scenarios, the considerations matched their perceived theoretical definitions, and that no content areas were omitted. This study resulted in validation of the content, following …

Process Intervention For Water Recovery In Food Manufacture, Christian Michael Wisniewski

Theses and Dissertations

A case study has been conducted for the recovery of water from complex wastewater at a soluble coffee manufacturing factory. The study has evaluated separation methods for process intervention based on environmental and economic assessments. Water recovery was identified in two possible wastewater streams at the factory: the overall plant effluent and an intermediate stream before it enters on-site pre-treatment. A novel vibratory field membrane separation was tested at the laboratory scale using real factory wastewater and scaled-up using appropriate design protocols. Recovery of water from the intermediate stream proved the most effective, both environmentally and economically. The full-scale vibratory …

Synthesis Of Novel, Highly Bio-Based Monomeric Materials Derived From Lignocellulosic Biomass And Their Respective Epoxy Resins, Polycarbonates, And Polyesters, Joseph Randall Mauck

Theses and Dissertations

The development of high performance polymers from renewable feedstocks is a crucial step toward a global economy that is less dependent on fossil resources and has been a field of increasing study. The development of novel and interesting bio-based monomers, resins, and functional building blocks is critical to the improvement of polymers produced across the field, as well as to increasing the resource base from which chemical and materials engineers can draw to meet specific polymer property requirements. To this end, interesting tri-functional (trisguaiacol) and 4-vinyl guaiacol based hetero-difunctional monomers were developed and screened for preliminary polymer properties. The applications …

Sustainable P2 Design For Batch-Based Specialty Chemical Manufacture, Brigitte Pastore

Theses and Dissertations

A case study has been conducted on the reduction of n-methyl-2-pyrrilodone (NMP) solvent waste in the manufacture of polyimide and polybenzoxazole precursors. The evaluation includes the environmental and economic assessment of solvent recovery and substitution strategies. A two-step distillation process proved effective in recovering 95% of the NMP at a purity of 99.97% from the aqueous solvent waste stream. Yearly operating costs were reduced by 83% and total life cycle emissions were reduced by 44%, due to reduction in virgin NMP use and hazardous waste disposal. With capital acquisition, the recovery option would still result in a net present value …

Lignin-Derived Thermosetting Vinyl Ester Resins For High Performance Applications, Daniel Rogers

Theses and Dissertations

Vinyl ester (VE) resins are utilized to produce polymer matrix composites for use in a wide range of applications due to possessing relatively high moduli, strengths, and glass transition temperatures while maintaining low weight and cost. VE resins often contain high concentrations of a petroleum-based reactive diluent (RD), such as styrene. Many of the commonly used RDs have been designated as hazardous air pollutants, potential carcinogens, and volatile organic compounds. Renewable VE resins and RDs with similar performance to petroleum-based RDs are desired to potentially mitigate the aforementioned hazards as well as to facilitate the transition from petrochemical feedstocks to …

Synthesis And Characterization Of Vanillyl Alcohol Based Thermosetting Epoxy Resins, Eric Hernandez

Theses and Dissertations

Lignin is a natural and abundant renewable material composed of crosslinked phenylpropenyl units that when strategically depolymerized could potentially yield renewable bio-based aromatic building blocks for applications in high-performance thermosetting epoxy resins. Vanillyl alcohol, a lignin derived aromatic diol, is a potential platform chemical for the production of renewable bisphenols and epoxy thermosets. A new bio-based bisphenol (bisguaiacol) was synthesized via electrophilic aromatic condensation of vanillyl alcohol and guaiacol, from which diglycidyl ether of bisguaiacol (DGEBG) was prepared via epoxidation with epichlorohydrin.The thermomechanical properties of DGEBG blended with a commercial BPA-based epoxy resin and cured with a diamine were investigated …