Carbon Dioxide Capture Potential Of Chitosan-Nanocrystalline Cellulose Aerogel Composite Materials: Synthesis, Functionalization, And Characterization,
2023
American University in Cairo
Carbon Dioxide Capture Potential Of Chitosan-Nanocrystalline Cellulose Aerogel Composite Materials: Synthesis, Functionalization, And Characterization, Victor Oghenekohwo
Theses and Dissertations
The carbon dioxide capture technology has been established as an invaluable player in the current global efforts to allay the warming of the planet and climate change. In this connection, the study centers on the valorization of waste organic materials for the application described herein. The sorbents, sourced from a combination of by-products of food processing and agricultural residue waste products, viz. seafood waste and sugarcane bagasse, showed prospects for selective carbon dioxide capture, adsorbing up to 5.78 mg/g of the gas at 273 K and 2.82 mg/g at 298 K, as observed on the Micromeritic ASAP 2020 surface area …
Polyethersulfone Thin-Film Nanocomposite Membrane Embedded With Amine-Functionalized Graphene Oxide For Desalination Applications,
2023
American University in Cairo
Polyethersulfone Thin-Film Nanocomposite Membrane Embedded With Amine-Functionalized Graphene Oxide For Desalination Applications, Ahmed Bahaeldin
Theses and Dissertations
Thin-film nanocomposite (TFN) desalination membranes were prepared based on a polyethersulfone (PES) support, where the polyamide (PA) layer was embedded with amine-functionalized graphene oxide (GO). The effect of adding various concentrations of functionalized and un-functionalized GO on the desalination performance, hydrophilicity, and morphology of the membranes was additionally assessed throughout this work. Scanning electron microscopy (SEM) measurements were used to assess the morphology of the membranes in combination with Brunauer-Emmett-Teller (BET) analysis. Contact angle measurements were used to gauge the hydrophilicity of the synthesized membranes. The membrane with the best desalination performance contained 1x10-3 wt/vol% of functionalized GO in …
Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent,
2023
Balai Besar Tekstil
Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani
Journal of Materials Exploration and Findings (JMEF)
Biduri fiber (Calotropis gigantea) is a natural hollow fiber with hydrophobic and oleophilic properties potentially used as oil spilled sorbent from seawater. This study aims to determine the absorption capacity and efficiency of the Biduri fiber and membrane to fuel oil. Measurement of oil absorption to seawater was carried out at various fiber weights (0.5-1.5 g), fiber composition (50-95%), contact time (10-90 minutes), temperature (30 and 50°C), and compared with commercial products. The results showed that the fiber weight variation of 0.5-1.5 g has an average absorption efficiency of 96.67%, and the highest absorption was obtained in a weight of …
Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties,
2023
Murray State University
Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties, Elizabeth Mcgrew, Kevin M. Miller Phd
Posters-at-the-Capitol
Cellulose, an inexpensive and renewable biomacromolecule, represents an intriguing synthetic foundation for new materials with task-specific properties. Here, we wish to report a synthetic route for functionalizing cellulose with a side chain containing two ionic liquid functional groups using azide-alkyne ‘click’ cyclization strategy, followed by quaternization of the two resulting heterocycles (1,2,3-triazole and imidazole). Through this functionalization strategy, the resulting cellulosic materials exhibited significant softening, with several glass transition (Tg) values observed below room temperature, indicating the amorphous nature of the materials, with the Tg dependent on both the length of the side chain and the …
Sunflower Oil-Based Polyol In Flame-Retardant Rigid Polyurethane Foams,
2022
Pittsburg State University
Sunflower Oil-Based Polyol In Flame-Retardant Rigid Polyurethane Foams, Magdalene Asare
Electronic Theses & Dissertations
The current shift from solely depending on petroleum sources to seeking renewable alternatives is due to their fast depletion, spike in prices, and the need to reduce our carbon footprint. For instance, the polyurethane industry currently calls for renewable and less toxic polyols and isocyanates for their synthesis over the traditionally used ones. To tackle an aspect of this matter, this work investigates the generation of polyol from sunflower oil, and further probes their use in rigid foams, one of the widely utilized polyurethanes. Epoxidation and ring-opening reactions were used to convert the sunflower oil into a more reactive form, …
Bio-Based Uv-Curable Films And The Effect Of Bio-Content On The Properties Of The Films,
2022
Pittsburg State University
Bio-Based Uv-Curable Films And The Effect Of Bio-Content On The Properties Of The Films, Sahilkumar Chaudhary
Electronic Theses & Dissertations
The use of renewable resources in film formation has become a new focal point for industry because it is abundantly available and has less carbon emission during production than traditional ones. This has drawn researchers to investigate the functionality of bio-based raw materials and their end-usage. By modifying their chemical structures, the properties of these films like thermal resistance, impact resistance, and chemical resistance can be increased. In this research, limonene was used as a partial replacement for petroleum-based chemicals in film formation. A two-step chemical process was carried out to modify the limonene and the final product was used …
Elucidating The Importance Of Structure, Surfaces, And Interfaces In Polymer Nanoparticles And Nanocomposites,
2022
University of Tennessee, Knoxville
Elucidating The Importance Of Structure, Surfaces, And Interfaces In Polymer Nanoparticles And Nanocomposites, Jacob E. Fischer
Doctoral Dissertations
This dissertation details research conducted to elucidate the importance of structure, surfaces, and interfaces in both polymeric nanoparticles and polymer nanocomposites. The fundamental understanding that is garnered in these studies provides a foundation to rationally develop nanocomposites tailored for unique functionalities, performance and applications.
Soft polymeric nanoparticles, have shown to imbue non-traditional diffusive properties, the strength of which decreases with crosslinking density of the nanoparticle. The crosslinking dependent morphology of these nanoparticles is first characterized in a dilute solution of good solvent (Chapter 2). The scattering results revealed that the structure ranges from a swollen polymer in good solvent (0% …
Controlling Polymer Molecular Structure And Morphology: From Illumination Of Conjugated Polymers To Polymer Chain Depolymerization,
2022
University of Tennessee, Knoxville
Controlling Polymer Molecular Structure And Morphology: From Illumination Of Conjugated Polymers To Polymer Chain Depolymerization, Josh Moncada
Doctoral Dissertations
Polymers remain a prominent component of our lives, and finding methods to control their structure or morphology are needed to tune material properties. This dissertation reports methods to alter the conformation, morphology, or structure of polymeric materials. Chapter two describes the impact of exposure to white light during annealing of conjugated polymer blends on their morphology and optoelectronic performance. The observed changes in the morphology correlate strongly to the variation in photoluminescence (PL) with illumination, including that the PL varies less with illumination at higher Poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] loadings, offering foundational understanding to guide the structure and optoelectronic performance of conjugated polymer …
Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites,
2022
University of Texas at El Paso
Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites, Sergio Dante Favela
Open Access Theses & Dissertations
This research will be divided into two sections. The first section discusses direct ink writing and thermomechanical characterization for thermoset composites. The thermoset ink is prepared with fillers aiding the printing process by modifying the rheology of the ink and geometry retention by allowing for the part to have an initial UV cure step. Three specimen formulations with different weight percentages were printed by material extrusion in the shape of tensile specimens following ASTM standard D638 to characterize the mechanical properties at room temperature, 100â?? and 200â??. Furthermore, the ink resin was characterized through DSC, TGA, and rheology testing. The …
Thermal Degradation Of Erythritol,
2022
California Polytechnic State University, San Luis Obispo
Thermal Degradation Of Erythritol, Sudheendra Gamoji
Physics
The Insulated Solar Electric Cooker (ISEC) is a double walled Aluminum pot with a resistive heater directly connected to a solar panel whose goal is to create and disseminate cheap solar cookers in rural areas that primarily rely on biomass for cooking. Phase Change Materials (PCMs) like Erythritol, a sugar substitute, take a tremendous amount of energy to melt, and when they solidify they release the energy. Through the use of PCMs, the ISECs will produce enough heat to cook food even after the sun sets. However, PCMs like Erythritol degrade over repeated heat exposure, so the purpose of this …
Polymer Mimetics For Soil Modeling And Detection Of Biomarkers,
2022
Louisiana State University
Polymer Mimetics For Soil Modeling And Detection Of Biomarkers, Md Ragib Hasan
LSU Doctoral Dissertations
The population of the world is increasing day by day and is expected to reach 9.8 billion by the year 2050. The ever-increasing demand for agricultural products is putting an unprecedented strain on the world's soils as the human population continues to expand. Soil degradation caused by over-farming and the agrochemicals (fertilizers, pesticides, etc.) used in agriculture is a growing problem, although its causes remain murky. In addition, little is understood about the molecular-level interactions of substances that are subsequently introduced to soils, such as agricultural chemicals (ACs). Therefore, it is expected that these constraints may be circumvented by the …
Intracellular Delivery Of Therapeutic Biomolecules Through Versatile Polymer Nanotechnology,
2022
University of Massachusetts Amherst
Intracellular Delivery Of Therapeutic Biomolecules Through Versatile Polymer Nanotechnology, David C. Luther
Doctoral Dissertations
Advancing pharmaceutical technology has made it possible to treat diseases once considered ‘undruggable.’ Access to these new pharmaceutical targets is possible thanks to the advent of protein and nucleic acid therapeutics. Responses to the COVID-19 pandemic, as well as cutting-edge treatments for cancer and multiple sclerosis have centered on these biologic therapies, promising even greater value in the future. However, their utility is limited at a cellular level by inability to cross the plasma membrane. Nanocarrier technologies encapsulate therapeutics and facilitate uptake into the cell but are often trapped and degraded in endosomes. Arginine-functionalized gold nanoparticles (Arg-NPs) provide efficient, direct …
Expanding The Polymer Zwitterion Library – Novel Phosphonium-Based Polymer Zwitterions And Analogous Structures,
2022
University of Massachusetts Amherst
Expanding The Polymer Zwitterion Library – Novel Phosphonium-Based Polymer Zwitterions And Analogous Structures, Marcel U. Brown
Doctoral Dissertations
This dissertation encompasses the synthesis, characterization and application of novel polymer zwitterions that significantly expand the library of available zwitterionic polymers. Their facile synthesis is facilitated by the preparation of a novel functional sultone precursor molecule, which can be ring-opened by commercially available phosphine, amine and sulfide nucleophiles, affording phosphonium, ammonium or sulfonium sulfonate monomers, respectively. Most notably, this work describes the invention of phosphonium-based polymer zwitterions, establishing a new class of zwitterionic polymer structures with unique solution and interfacial properties. Furthermore, the incorporation of these phosphonium sulfonates into block copolymer architectures with conventional polymer zwitterions, and the resulting switchable …
Conformation Of The U12-U6atac Snrna Complex Of The Minor Spliceosome And Binding By Ntc-Related Protein Rbm22,
2022
The Graduate Center, City University of New York
Conformation Of The U12-U6atac Snrna Complex Of The Minor Spliceosome And Binding By Ntc-Related Protein Rbm22, Joanna Ciavarella
Dissertations, Theses, and Capstone Projects
Splicing of precursor messenger (pre-m)RNA is a critical process in eukaryotes in which the non-coding regions, called introns, are removed and coding regions, or exons, are ligated to form a mature mRNA. This process is catalyzed by the spliceosome, a multi-mega Dalton ribonucleoprotein complex assembled from five small nuclear ribonucleoproteins (snRNP) in the form of small nuclear (sn)RNA-protein complexes (U1, U2, U4, U5 and U6) and >100 proteins. snRNA components catalyze the two transesterification reactions while proteins perform critical roles in assembly and rearrangement. U2 and U6 snRNAs are the only snRNAs directly implicated in catalyzing the splicing of pre-mRNA. …
How Dynamic Bond Results In The Unique Viscoelastic Behavior Of The Associating Polymers,
2022
University of Tennessee, Knoxville
How Dynamic Bond Results In The Unique Viscoelastic Behavior Of The Associating Polymers, Sirui Ge
Doctoral Dissertations
Associating polymer is a special kind of polymer possessing transient reversible bonds in addition to the conventional covalent bonds. The reversible bonds provide unique dynamics and fascinating viscoelastic properties, resulting in attractive applications for these polymers, such as self-healing and shape memory materials. Despite many years of studies, the understanding of dynamics of polymers with reversible bonds, especially on molecular level, is still in the rudimentary stage, preventing the rational design of the potential novel functional materials based on associating polymers. In this dissertation, we provide a detailed and quantitative understanding of the dynamics and viscoelastic properties of associating polymers. …
Functional Bottlebrush Polymer Additives For Thin Films And Coatings,
2022
University of Tennessee, Knoxville
Functional Bottlebrush Polymer Additives For Thin Films And Coatings, Travis S. Laws
Doctoral Dissertations
Bottlebrush polymers are a class of highly branched polymers consisting of polymeric side chains that are densely grafted to a linear backbone. Their highly branched architecture results in surface enrichment across a broad range of materials. The goal of my research has been centered around the design of functional bottlebrush polymers and their use as surface active additives in blend films and coatings.
In the first chapter, we examine the segregation behavior of polystyrene bottlebrushes that are blended with linear polystyrene. We systematically vary the lengths of the bottlebrush backbone (Nb), side-chain (Nsc), and the linear matrix (Nm) in order …
Bbt Acoustic Alternative Top Bracing Cadd Data Set-Norev-2022jun28,
2022
East Tennessee State University
Bbt Acoustic Alternative Top Bracing Cadd Data Set-Norev-2022jun28, Bill Hemphill
STEM Guitar Project’s BBT Acoustic Kit
This electronic document file set consists of an overview presentation (PDF-formatted) file and companion video (MP4) and CADD files (DWG & DXF) for laser cutting the ETSU-developed alternate top bracing designs and marking templates for the STEM Guitar Project’s BBT (OM-sized) standard acoustic guitar kit. The three (3) alternative BBT top bracing designs in this release are
(a) a one-piece base for the standard kit's (Martin-style) bracing,
(b) 277 Ladder-style bracing, and
(c) an X-braced fan-style bracing similar to traditional European or so-called 'classical' acoustic guitars.
The CADD data set for each of the three (3) top bracing designs includes …
Designing Dynamic And Degradable Polymeric Materials With Thiol-X Chemistries,
2022
The University of Southern Mississippi
Designing Dynamic And Degradable Polymeric Materials With Thiol-X Chemistries, Reese Sloan
Dissertations
With plastic production poised to increase in coming years, there arises a need to develop new polymeric materials designed to combat the global pollution crisis. A commonly utilized approach in addressing this challenge is to employ a responsive functional moiety into the polymer architecture. Thiol-X reactions, a commonly utilized class of “click” reactions, have garnered broad implementation in new stimuli-responsive materials. This work specifically focuses on utilizing radical-mediated thiol-ene coupling and base-catalyzed thiol-isocyanate reactions to develop a library of ternary thiol-ene/thiourethane covalent adaptable networks (CANs) and hydrolytically labile poly(thioether ketal) thermoplastics. CANs are a class of network materials capable of …
Bbt Side Mold Assy,
2022
East Tennessee State University
Bbt Side Mold Assy, Bill Hemphill
STEM Guitar Project’s BBT Acoustic Kit
This electronic document file set covers the design and fabrication information of the ETSU Guitar Building Project’s BBT (OM-sized) Side Mold Assy for use with the STEM Guitar Project’s standard acoustic guitar kit. The extended 'as built' data set contains an overview file and companion video, the 'parent' CADD drawing, CADD data for laser etching and cutting a drill &/or layout template, CADD drawings in AutoCAD .DWG and .DXF R12 formats of the centerline tool paths for creating the mold assembly pieces on an AXYZ CNC router, and support documentation for CAM applications including router bit specifications, feeds, speed, multi-pass …
Biomass Estimation Of Marine Biofilms On Plastic Surfaces,
2022
California Polytechnic State University, San Luis Obispo
Biomass Estimation Of Marine Biofilms On Plastic Surfaces, Kian Banihashemi, Fernando Javier Gil
Biological Sciences
Plastics have become a major source of marine pollution, which threatens food safety and quality, human health, and marine ecosystems. Due to the drastic negative effects of plastics in a marine environment, alternative biodegradable plastics are being generated that are more eco-friendly and have less environmental impact. Though some of these plastics are known to biodegrade, the process of degradation for bioplastics has not been heavily studied in a marine environment. This pilot project sought to both quantify the process of biodegradation and compare across different methods for effectiveness of biomass estimation, which serves as an indicator of biodegradation. Plastics …