Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, 2023 Universitas Indonesia
Combined Risk Based Inspection And Fault Tree Analysis For Repetitive 3-Phase Line Piping Leakage At West Java Offshore Topside Facility, Dona Yuliati, Akhmad Herman Yuwono, Datu Rizal Asral, Donanta Dhaneswara
Journal of Materials Exploration and Findings (JMEF)
Hydrocarbon releases might result in serious consequences in various aspects. In addition to the contribution to environmental pollution, repetitive leakages need high repair costs. This study aim is to minimize potential repetitive leakage for other typical 3-phase piping systems. We conducted the risk assessment by adopting Risk Based Inspection (RBI) API 581 to identify risk level, calculating piping lifetime, recommended inspection plan and mitigations. The most relevant root causes can be obtained through quantitative Fault Tree Analysis (FTA). Observation and investigation was taken from eight 3-phase piping systems that experienced repetitive leakages. It has been found that the risk level …
Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, 2023 University of Indonesia, Depok
Nitrogen Gas Quenching Pressure Effect On Bs S155 Alloy Steel In Vacuum Furnace, Agus Mulyadi Hasanudin, Eddy Sumarno Siradj
Journal of Materials Exploration and Findings (JMEF)
The production of metal and alloy products requires the use of heat treatment, when during the heat treatment process, quenching is a crucial step. The quenching medium can be anything from water, a salt bath, oil, air and gas. In a vacuum furnace, pressurized gas, most frequently nitrogen (N2) gas, serves as one of the quenching mediums. One of the drawbacks of the quenching process is the distortion and dimensional change of the parts. This paper aims to investigate the influence of nitrogen gas quenching pressure on the distortion and dimensional change of aerospace actuator gear planet parts …
Enhanced Mechanical Strength Of Soybean Oil-Based Non-Isocyanate Polyurethane Adhesive For Wood Application By Introducing Nanofillers, 2023 Pittsburg State University
Enhanced Mechanical Strength Of Soybean Oil-Based Non-Isocyanate Polyurethane Adhesive For Wood Application By Introducing Nanofillers, Vatsal Chaudhari
Electronic Theses & Dissertations
Polyurethane (PU) is a versatile material that finds extensive use in various industries including bedding, construction, automotive, and packaging. Historically, this particular polymer relied significantly on petrochemical resources, a practice that was considered to have negative environmental impacts. The conventional method for preparing PU involves the use of isocyanate, which is a disadvantage due to its negative impact on the environment and human health. The resolution of this problem entails identifying an appropriate substitute for petroleum-derived products that minimize their impact on both the environment and human health. The researchers earlier utilized soybean oil, for the formulation of PUs in …
Optimization Of Transition-Metal Inclusive Carbon Aerogels For Electrochemical Energy Applications, 2023 Pittsburg State University
Optimization Of Transition-Metal Inclusive Carbon Aerogels For Electrochemical Energy Applications, Allen Dalton Davis
Electronic Theses & Dissertations
The ever-growing need for energy alongside rising concerns for climate change demands the development of renewable energy technologies. Hydrogen fuel cells are a promising technology that can serve to either supplement energy generation or act as a lone power source. Yet for these devices to be truly green, the hydrogen that serves as fuel must be procured from a renewable resource. Electrolytic water splitting is a process that allows for the dissociation of water into H2 and O2. For this process to be practical, the electrolyzer needs to demonstrate high efficiency and stability, as well as a …
Exploring Soybean Oil-Based Polyol And Effect Of Non-Halogenated Flame Retardants In Rigid Polyurethane Foam, 2023 Pittsburg State University
Exploring Soybean Oil-Based Polyol And Effect Of Non-Halogenated Flame Retardants In Rigid Polyurethane Foam, Sahithi Kondaveeti
Electronic Theses & Dissertations
To address the increasing demand for sustainable biomaterials due to the depletion of fossil fuel resources and growing environmental concerns, a new type of biodegradable and environmentally friendly rigid polyurethane foam (RPUF) has been synthesized. These foams are derived from chemically modified soybean oil-based polyol obtained from soybean oil by epoxidation followed by a ring-opening reaction. Polyurethane foam is generally used in construction, furniture, and automobile industries but is highly flammable and releases toxic gases and smoke during combustion. In this study, a highly efficient synergistic effect halogen-free flame-retardant (FR) melamine salt, 2-carboxyethyl(phenyl)phosphinic acid melamine salt (CMA) was synthesized from …
Synthesis Of Poly(Styrene-Co-Butyl Acrylate) Pickering Emulsion With Montmorillonite Nanoparticles And Its Comparison With Sodium Dodecyl Sulfate Surfactant On Affecting The Water Barrier Properties Of Coated Paper, 2023 University of Maine
Synthesis Of Poly(Styrene-Co-Butyl Acrylate) Pickering Emulsion With Montmorillonite Nanoparticles And Its Comparison With Sodium Dodecyl Sulfate Surfactant On Affecting The Water Barrier Properties Of Coated Paper, Chidubem H. Uchefuna
Electronic Theses and Dissertations
Water-borne barrier dispersion coatings on paper have emerged as an alternative to extrusion coatings on paper due to improved recycling, high application speed, and other end of life attributes. Pigments are often added to improve the performance of dispersion coatings. The use of pigments to form a Pickering emulsion during the polymerization step for the production of a barrier coating on paper has not been discussed in the literature.
In this study, montmorillonite (MMT) pigment varied from 0-6 % pigment volume concentration (PVC) was used to synthesize dispersion coatings consisting of poly(styrene-co-butylacrylate) latex and compared with sodium dodecyl …
Material Formulation And Process Optimization Towards Fabricating Robust 3d Printed Structures, 2023 University of Tennessee, Knoxville
Material Formulation And Process Optimization Towards Fabricating Robust 3d Printed Structures, Austin Riggins
Doctoral Dissertations
This dissertation focuses on understanding and addressing the fundamental physicochemical phenomena that lead to weak interfaces and structural warpage in material extrusion 3D printing. Polymeric feedstocks used for this manufacturing technique were manipulated through the incorporation of additives that alter the dynamics of the matrix during and after printing. In Chapter II, adhesion between layers of structures printed from PEEK was strengthened through a combination of low-molecular weight additive incorporation and post-printing thermal annealing. Chapter III reports a method for decreasing the irreversible thermal strain of structures printed from poly(lactic acid) by introducing nanographene and photoinitiator additives into the feedstock …
Upcyclying Of Polyethylene Terephtalate By Addition Of Thermoplastic Elastomer, 2023 University of Texas at El Paso
Upcyclying Of Polyethylene Terephtalate By Addition Of Thermoplastic Elastomer, Diego Francisco Bermudez
Open Access Theses & Dissertations
Continual overconsumption of single-use plastics has generated challenges of solid waste management across the United States. Common plastic waste management solutions, such as landfill, have caused the migration of contaminants into the environment consequently affecting not only the health of wildlife, but also that of human beings. Alternative strategies for the handling of single-use plastic such as polyethylene terephthalate (PET), used in the food packaging industry, can ultimately help mitigate the noxious consequences of single-use plastics affecting entire ecosystems. This study demonstrates a potential avenue of materials upcycling by studying the effects of coupling PET with the thermoplastic elastomer styrene-ethylene-butylene-styrene …
Nanoparticles And The Environment: Biopolymer Grafted Cellulose And Screen-Printed Carbon Nanotube Composites, 2023 California Polytechnic State University, San Luis Obispo
Nanoparticles And The Environment: Biopolymer Grafted Cellulose And Screen-Printed Carbon Nanotube Composites, Dominique Henry Porcincula
Master's Theses
A host of environmental issues will define the state of the environment in the 21st century, with plastic pollution and water shortages among them. While solutions to these problems require large-scale, multipronged solutions, one way we can address them is through material innovation and the use of nanoparticles.
In the first project, we address the issue of plastic pollution by creating nanocomposites of biodegradable polymers (PLA and PCL) with cellulose nanofibrils. Here, PLA and PCL are grafted from the surface of cellulose nanofibrils via ring-opening polymerization of cyclic ester monomers. Polymer-grafted cellulose (PGC) is characterized with structural analysis, solubility …
The Influence Of Ion-Ion Correlations On Conductivity In Concentrated Ionic Systems, 2023 University of Tennessee, Knoxville
The Influence Of Ion-Ion Correlations On Conductivity In Concentrated Ionic Systems, Md Dipu Ahmed
Masters Theses
This study delves into the fascinating realm of concentrated ionic systems, such as ionic liquids, superionic materials, organic ionic plastic crystals, and polyelectrolytes, which hold immense potential for energy storage applications. The focus is on understanding the intricate role of ionic correlations in shaping their ionic conductivity behavior. These correlations can either boost or impede conductivity, yet their underlying mechanisms remain elusive. Through extensive investigation of various materials, including ionic liquids with differing anionic masses, pure organic ionic plastic crystals, and doped systems, this research employs advanced techniques like dielectric spectroscopy and innovative momentum conservation models to quantify these correlations. …
Synthesis Of Block Copolymer Additives For Examining Phase Morphology And Improving Mechanical Properties Of Thermoplastics Elastomers., 2023 University of Tennessee, Knoxville
Synthesis Of Block Copolymer Additives For Examining Phase Morphology And Improving Mechanical Properties Of Thermoplastics Elastomers., Bishal Upadhyay
Masters Theses
Polystyrene-block-poly(1,4-butaidene)-block-polystyrene (PS-PB-PS) triblock copolymers are one of the most widely studied thermoplastic elastomers (TPEs) due to their ease of synthesis, non-polar nature, and commercial applicability. Like many block copolymers, incompatibility between PS and PB causes these TPEs to undergo microphase segregation. Many studies have examined the mechanical properties of blends of TPEs and PS homopolymer additives. However, there have been few studies focused on understanding the morphology and mechanical properties of blends of TPEs and copolymer additives with different architectures. Herein, I describe the synthesis of linear and graft copolymer additives based on the random copolymers poly(methyl methacrylate-random-cyclohexyl methacrylate) (PrC). …
Polymer-Based Nanotherapeutics To Combat Difficult-To-Treat Bacterial Infections, 2023 University of Massachusetts Amherst
Polymer-Based Nanotherapeutics To Combat Difficult-To-Treat Bacterial Infections, Jessa Marie V. Makabenta
Doctoral Dissertations
The continuous emergence and spread of antibiotic-resistant bacteria are a global health emergency, debilitating the capability to prevent and cure various infectious diseases that were once treatable. Antibiotic therapy is further rendered ineffective due to biofilm formation and the ability of bacteria to thrive and colonize inside mammalian cells. Given the diminishing efficacy of available antibiotics combined with the scarcity of new therapeutics entering the antibiotic pipeline, innovative treatment strategies are urgently in demand. Nanomaterial-based strategies offer ‘outside of the box’ approach for the treatment of antibiotic-resistant bacterial infections. Nanomaterials feature tunable physicochemical properties that can be carefully modified to …
Reactive Chemistries For Protein Labeling, Degradation, And Stimuli Responsive Delivery, 2023 University of Massachusetts Amherst
Reactive Chemistries For Protein Labeling, Degradation, And Stimuli Responsive Delivery, Myrat Kurbanov
Doctoral Dissertations
Reactive chemistries for protein chemical modification play an instrumental role in chemical biology, proteomics, and therapeutics. Depending on the application, the selectivity of these modifications can range from precise modification of an amino acid sequence by genetic manipulation of protein expression machinery to a stochastic modification of lysine residues on the protein surface. Ligand-Directed (LD) chemistry is one of the few methods for targeted modification of endogenous proteins without genetic engineering. However, current LD strategies are limited by stringent amino acid selectivity. To bridge this gap, this thesis focuses on the development of highly reactive LD Triggerable Michael Acceptors (LD-TMAcs) …
Machine Learning Modeling Of Polymer Coating Formulations: Benchmark Of Feature Representation Schemes, 2023 University of Massachusetts Amherst
Machine Learning Modeling Of Polymer Coating Formulations: Benchmark Of Feature Representation Schemes, Nelson I. Evbarunegbe
Masters Theses
Polymer coatings offer a wide range of benefits across various industries, playing a crucial role in product protection and extension of shelf life. However, formulating them can be a non-trivial task given the multitude of variables and factors involved in the production process, rendering it a complex, high-dimensional problem. To tackle this problem, machine learning (ML) has emerged as a promising tool, showing considerable potential in enhancing various polymer and chemistry-based applications, particularly those dealing with high dimensional complexities.
Our research aims to develop a physics-guided ML approach to facilitate the formulations of polymer coatings. As the first step, this …
Supramolecular And Covalent Crosslinking Of Organic Semiconductors, 2023 University of Windsor
Supramolecular And Covalent Crosslinking Of Organic Semiconductors, Audithya Narasimha Nyaychavadi
Electronic Theses and Dissertations
Organic semiconductors are a class of materials that are uniquely positioned to be the platform for next generation technologies that possess properties that transcend the limitations of silicon materials such as inherent biocompatibility, stretchability and degradability, all while being manufactured sustainably and at lower cost. These materials have good electronic properties that arise from their π-delocalized network, which when combined with rational chemical design allow for highly specialized materials for targeted applications and properties. Furthermore, their ability to be solution processed provides an avenue for low-cost, scalable mass production techniques, such as printing and roll-to-roll coating. Despite these advantages, however, …
Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, 2023 University of Arkansas-Fayetteville
Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley
Graduate Theses and Dissertations
Poly(ionic liquid)s (PILs) are a fascinating subclass of strong polyelectrolytes formed from polymerizable ionic liquids. As a result of their unique properties and counterion exchangeability, PILs can exhibit conformation structure or material property changes in response to external stimuli such as changes in pH/ionic environment, magnetic fields, and electric potentials. In Chapter 1, a comprehensive review of PILs design as well as their stimuli-responsive behavior is provided. Additional motivation for each dissertation chapter is also discussed. In Chapter 2, magnetically responsive PILs (MPILs) are developed from complexing paramagnetic salts with a random PIL copolymer containing a metal-coordinating co-monomer, acrylamide. A …
Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, 2023 Clemson University
Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, Mahsa Shabani Samghabady
All Theses
Polylactic acid (PLA) is a biopolymer made from renewable resources such as sugar and corn. PLA filament is a popular material used in Fused Deposition Modeling (FDM) 3D-printing. While this material has many advantages, all the failed parts, support structures, rafts, nozzle tests, and the many prototype iterations during the 3D-printing process contribute to the plastic pollution and release of greenhouse gases. Although PLA is biodegradable, it can take years to degrade in landfills. Instead of throwing away PLA waste and buying new filaments, PLA can be recycled. Amongst the different recycling technologies, mechanical recycling is the most environmentally friendly. …
Redox-Active Polymerization Catalysts And Their Applications, 2023 University of Tennessee, Knoxville
Redox-Active Polymerization Catalysts And Their Applications, Nicholas M. Shawver
Masters Theses
Traditional catalyst systems are reliable means to produce polymers with well-defined architectures and thermomechanical properties; however, they are often limited by a narrow monomer scope and their ability access few, if any, advanced polymer architectures. To address this limitation, a new class of catalysts have recently emerged that feature redox-active moieties that may access advanced architectures through catalyst electronic modulation that arises from redox events occurring on the ligand scaffold or at the active metal center itself. For example, researchers have explored the ability of redox-active catalysts to impart “on-off” kinetic control during ring-opening polymerizations and their ability to access …
Functional Nanocomposite Coatings For Use In Food Packaging, 2023 California Polytechnic State University, San Luis Obispo
Functional Nanocomposite Coatings For Use In Food Packaging, Camden N. Webb
Master's Theses
Plastics are a class of materials known for their cost and property advantages, increasing significantly in their usage worldwide. Unfortunately, these benefits come with an increasingly concerning environmental impact. A combination of inadequate disposal options and combinations of materials have led to environmental disasters that will impact generations. One of the worst areas for plastic waste is food packaging. Plastic as a material generally excels at durability and longevity, but as food packaging, it outlives its intended purpose by several orders of magnitude. This leads to plastic food packaging materials sitting in landfill or leading to the environment for hundreds …
Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, 2023 University of Arkansas, Fayetteville
Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino
Biological Sciences Undergraduate Honors Theses
This honors thesis aims to investigate the reusability and performance of cell coatings for cell therapy applications. Cell therapy, which involves the use of human cells to repair or replace damaged tissues, holds immense potential for medical advancements. However, ensuring the survival and functionality of transplanted cells remains a significant challenge. We focused on studying the effectiveness of coatings applied to cells for improved cell growth and viability. The research project involved the preparation of the coatings using a layer-by-layer method and the subsequent seeding of cells. The coated cells were then subjected to a series of experiments to assess …