Engineering Commons^™

Polylactic Acid (Pla) Containing Talc Microparticles And Amorphous Polyhydroxyalkanoates (Aphas) For Improved Barrier And Mechanical Properties In Food Packaging, Mohammed Alfaifi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Polylactic acid (PLA) is a biobased and compostable polymer that is increasingly being used as an alternative to petroleum-based, non-biodegradable polymers for single-use food packaging due to its environmental benefits. It is also commercially available in large quantities, and it can be processed like polyethylene. However, it has a higher water-vapor permeability (WVP) as compared to polyolefins and polyethylene terephthalate that are the incumbent materials. This results in a competitive disadvantage in employing PLA for packaging baked goods since the shelf life of the food is likely to be reduced. In the past, barrier properties of PLA were improved by …

Strategies For Process Systems Mapping And Control Based On Operability Analysis, Victor Manuel Cunha Alves

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation aims to develop strategies for process systems engineering (PSE) mapping using models, emerging tools and algorithms motivated by process operability analysis research. Such strategies will be employed to ensure simultaneous design and control of large-scale industrial systems. The emerging tools and techniques in this research include supervised machine learning-based (ML-based) operability mapping, automatic differentiation (AD) for implicit mapping, and the development of a systematic mapping approach for control structure selection using operability analysis. Thus far, the developed operability algorithms either recur to nonlinear programming (NLP) solutions which are computationally expensive or to linearizing the underlying modeling task at …

Investigation Of Synergistic Effect Between Polystyrene And Polyethylene Under Conventional Thermal Heating And Microwave Heating, Thang Luong

Graduate Theses, Dissertations, and Problem Reports (ETD)

Single-use plastics (Low Density Polyethylene, LDPE; Polystyrene, PS; Polypropylene, PP) are increasingly used in the modern world, with their usage growing every year. An effective method to manage the resulting waste is urgently needed, as landfilling and incineration have proven harmful to the environment in the long term. Mechanical recycling may not maintain the desirable characteristics of the single-use plastics through several cycles. Pyrolysis emerges as a promising approach to address plastic waste. Given that single-use plastic waste often comes in a mixture, combining plastic in the feedstock is a viable solution to effectively convert these polymers altogether to gain …

Electron-Induced Chemical Transformations In Polymer Films: Understanding The Role Of Electrons In Euv Lithography, Maximillian Mueller

Master's Theses

The next generation of computer processors, memory, and nano-scale technologies all rely on our ability to create patterns at the nanometer scale reliably. Extreme ultraviolet (EUV) lithography can create sub-10 nm features by exposing photoresist materials, typically polymers or organic networks, to 13.5 nm, 92 eV light. At these energies, absorption of photons by the photoresist leads to the emission of a primary electron around 80 eV which inelastically scatters throughout the material, initiating chemistry and creating secondary electrons. The resulting cascade of electrons and chemical reactions remains poorly understood for most photoresist materials systems. This work aims to characterize …

Sustainable Materials For Environment − Multifunctional Material Made From Dead Leaves And Nanostructured Materials For Antibiotic Degradation, Siyuan Fang

Dissertations, Master's Theses and Master's Reports

As environmental pollution from industrial processes and human activities continues to rise, finding efficient approaches to recycle waste materials and degrade persistent contaminants becomes increasingly critical. Dead leaves, an abundant but underutilized biomass, present an opportunity for creating value-added materials if their biocomponents can be preserved and transformed. Simultaneously, antibiotics such as tetracycline are widely found in water bodies but pose serious ecological and health risks, necessitating effective degradation methods. This dissertation addresses these challenges by leveraging natural and nanostructured materials to develop multifunctional products and advanced photocatalytic processes.

Chapter 3 of this dissertation addresses the challenge of converting waste …

Preliminary Remote Identification Of Unstable Zone On Large-Scale Waste Dump At Mae Moh Mine Using Insar Technique, Chitra Buth

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mae Moh Mine is one of the largest lignite mine in Southeast Asia, operated by the Electricity Generating Authority of Thailand (EGAT). It is located in the northern part of Thailand, in Mae Moh district, Lampang province. In March 2018, a significant sliding incidence occurred at a waste dump site with sliding area of 1.56 km2 approximately, highlighting the pressing issue of instability within this large-scale waste dump area. This study aims to address this concern in the future and demonstrate an innovative method for investigating the failure by employing Interferometric Synthetic Aperture Radar (InSAR) technology. The methodology involves the …

Solvent-Free Manufacturing Of Lithium-Ion Battery Electrodes Via Cold Plasma, Zhiming Liang, Tianyi Li, Holden Chi, Joseph Ziegelbauer, Kai Sun, Ming Wang, Wei Zhang, Tuo Liu, Yang-Tse Cheng, Zonghai Chen, Xiaohong Gayden, Chunmei Ban

Chemical and Materials Engineering Faculty Publications

Slurry casting has been used to fabricate lithium-ion battery electrodes for decades, which involves toxic and expensive organic solvents followed by high-cost vacuum drying and electrode calendering. This work presents a new manufacturing method using a nonthermal plasma to create inter- particle binding without using any polymeric binding materials, enabling solvent-free manufacturing electrodes with any electrochemistry of choice. The cold-plasma-coating technique enables fabricating electrodes with thickness (>200 lm), high mass loading (>30 mg cm^-2), high peel strength, and the ability to print lithium-ion batteries in an arbitrary geometry. This crosscutting, chemistry agnostic, platform technology would increase energy density, …

Type-B Energetic Processes: Introduction And Invitation To Special Issue Of Energies, James Weifu Lee, Daniel P. Sheehan

Chemistry & Biochemistry Faculty Publications

[First paragraph] Currently, there is substantial scientific evidence for the existence of Type-B energetic processes on Earth, such as the naturally occurring transmembrane-electrostatically localized protons (TELP) thermotrophic properties in life [1]. A number of groundbreaking human-made Type-B energetic processes, including (but not limited to) “asymmetric function-gated isothermal electricity production” [2], “epicatalysis generating a temperature difference between catalysis-asymmetric filaments” [3], “artificially made asymmetric membrane concentration cell” [4,5], “Fu’s experiment on heat–electric conversion using surface electron emission under a static magnetic field” [6], and the “dynamic processes in superconductors indicating Type-B energetic process” [7,8,9] have been invented and/or experimentally demonstrated. The innovative …

Synthetic Approaches Of Carbohydrate Based Self-Assembling Systems, Guijun Wang, Anji Chen, Pramod Aryal, Jonathan Bietsch

Chemistry & Biochemistry Faculty Publications

Carbohydrate-based self-assembling systems are essential for the formation of advanced biocompatible materials via a bottom-up approach. The self-assembling of sugar-based small molecules has applications encompassing many research fields and has been studied extensively. In this focused review, we will discuss the synthetic approaches for carbohydrate-based self-assembling (SA) systems, the mechanisms of the assembly, as well as the main properties and applications. This review will mainly cover recent publications in the last four years from January 2020 to December 2023. We will essentially focus on small molecule self-assembly, excluding polymer-based systems, which include various derivatives of monosaccharides, disaccharides, and oligosaccharides. Glycolipids, …

Liposomes-Encapsulating Double-Stranded Nucleic Acid (Poly I:C) For Head And Neck Cancer Treatment, Vidit Singh, Anna Chernatynskaya, Lin Qi, Hsin Yin Chuang, Tristan Cole, Vimalin Mani Jeyalatha, Lavanya Bhargava, W. Andrew Yeudall, Laszlo Farkas, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Polyriboinosinic acid-polyribocytidylic acid (Poly I:C) serves as a synthetic mimic of viral double-stranded dsRNA, capable of inducing apoptosis in numerous cancer cells. Despite its potential, therapeutic benefits, the application of Poly I:C has been hindered by concerns regarding toxicity, stability, enzymatic degradation, and undue immune stimulation, leading to autoimmune disorders. To address these challenges, encapsulation of antitumor drugs within delivery systems such as cationic liposomes is often employed to enhance their efficacy while minimizing dosages. In this study, we investigated the potential of cationic liposomes to deliver Poly I:C into the Head and Neck 12 (HN12) cell line to induce …

Novel Modified Polyethersulfone High Temperature And Low Humidity Fuel Cell Membrane: Experimental And Simulation Study, Mohammed K. Al Mesfer, Muthanna H. Al-Dahhan, Mohd Danish, Mumtaj Shah

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Present Study Focuses on Synthesizing a High-Temperature Stable Membrane Working under Low Relative Humidity (RH) by Aminating the Traditional Polyethersulfone Polymer with Aniline for Fuel Cell Applications. a Condensed-Phase Optimized Molecular Potentials for Atomistic Simulation Studies Force Field-Based Molecular Dynamics Simulation Was Used to Explore the Microscopic Properties and Transport of Water and Hydronium (H3O+) Ions Across the Electrolyte at Varied Temperatures and RHs. COMSOL Calculates Oxygen and Hydrogen Concentrations after Examining the Polymer–ion Interaction with the Radial Distribution Function (RDF). the High H3O+ Diffusion Coefficient of the Aniline-Treated Membrane Shows the Benefit of the Modification. the RDF Confirmed …

Robust Triso-Fueled Pebble Identification By Digit Recognition, Roshan Kenia, Jihane Mendil, Ahmed Jasim, Muthanna Al-Dahhan, Zhaozheng Yin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Nuclear Power Plays a Vital Role in Providing Reliable and Clean Energy to Fulfill Increasing Demands in Electricity Worldwide. It Continues to Be an Essential Source of National Power Supply as Growing Concerns About Fossil Fuel Depletion, Global Warming, and Emissions Require Utilizing Sustainable Energy Sources. One Area Contributing to the Growth of Nuclear Power is the Development of Reactors that Have Enhanced Protection and Security, Thermal Efficiency, and Design. Reactor Efficiency Can Be Studied by the Burnup that Occurs When a TRISO-Fueled Pebble is Inserted into the Nuclear Core and Subsequently Removed. the Levels of Burnup Are Measured based …

Thermal Decomposition And Kinetic Parameters Of Three Biomass Feedstocks For The Performance Of The Gasification Process Using A Thermogravimetric Analyzer, Rania Almusafir, Joseph D. Smith

Chemical and Biochemical Engineering Faculty Research & Creative Works

Thermogravimetric analysis (TGA) is a powerful technique and useful method for characterizing biomass as a non-conventional fuel. A TGA apparatus has been utilized to experimentally investigate the impact of biomass feedstock diversity on the performance of the gasification of hardwood (HW), softwood (SW) pellets, and refuse-derived fuel (RDF) materials. The solid conversion rate and the volatile species formation rate have been estimated to quantify the rates of devolatilization for each material. In addition, the combustion kinetic characteristics of the three biomass feedstocks were investigated using TGA at different heating rates, and a thermal kinetic analysis was conducted to describe the …

Injectable Dendrimer Hydrogel Delivers Melphalan In Both Conjugated And Free Forms For Retinoblastoma, Remy C. Cooper, Juan Wang, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

We report the successful synthesis of an injectable dendrimer hydrogel (DH) carrying melphalan, a clinical drug for retinoblastoma treatment, in both conjugated and free forms. Polyamidoamine (PAMAM) dendrimer generation 5 (G5) is surface-modified with an acid-sensitive acetal-dibenzocyclooctyne linker and then undergoes azide-alkyne cycloaddition with melphalan-PEG-N3 conjugate to form G5-acetal-melphalan. During the DH gelation between G5-acetal-melphalan and PEG-diacrylate, free melphalan is added, resulting in a hydrogel (G5-acetal-melphalan-DH/melphalan) that carries the drug in both conjugated and free forms. Melphalan is slowly released from G5-acetal-melphalan-DH/melphalan, with the conjugated melphalan released more quickly at pH 5.3 due to acid-triggered acetal bond cleavage. The formulation's …

Thermal Management Of Adsorption-Based Biogas Upgrading Systems Via Incorporation Of Phase-Change Materials, Kyle Newport, Khaled Baamran, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Thermal management of adsorption columns is necessary to maintain their effectiveness while reducing the energy requirements of the overall separation process. In this work, we aimed at investigating the suitability of blending adsorbents with phase-change materials (PCMs) to adjust the thermal profile of a biogas upgrading column. A commercially available PCM (Nextek 28D) in quantities of 10, 20, and 30 wt. % was blended with zeolite 13X in two configurations, namely, traditional pellets and 3D-printed monoliths. The use of different structures allows for better analysis of thermal profiles and assessment of the effectiveness of the PCM in a packed bed …

Integrated Downhole-Measurement-Enabled Coiled Tubing And Mechanical Wireline Recovery Of E-Line Cable In A Live, Sour Gas Well, C. Villagrana, A. Abouganem, A. M. Afsal, M. Al-Dahhan, J. Delaune, W. R. Tapia, M. Amri

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study details a complex wire recovery operation in a live well that involved transitioning from coiled tubing (CT) to mechanical wireline (MWL), in both slickline [MA1] or braided line, to retrieve the wire in good condition and later hand it over to an electrical wireline (e-line) unit to spool it onto a drum. the operation was carried out on a live, sour gas well, demanding a unique setup and emphasizing safety. Two successful recovery operations removed a significant amount of e-line left in the well plus the upper section of the e-line bottomhole assembly (BHA) while safely pushing the …

Role Of Nitrogenous Functional Group Identity In Accelerating 1,2,3- Trichloropropane Degradation By Pyrogenic Carbonaceous Matter (Pcm) And Sulfide Using Pcm-Like Polymers, Han Cao, Jingdong Mao, Paul G. Tratnyek, Wenqing Xu

Chemistry & Biochemistry Faculty Publications

Groundwater contamination by 1,2,3-trichloropropane (TCP) poses a unique challenge due to its human toxicity and recalcitrance to degradation. Previous work suggests that nitrogenous functional groups of pyrogenic carbonaceous matter (PCM), such as biochar, are important in accelerating contaminant dechlorination by sulfide. However, the reaction mechanism is unclear due, in part, to PCM's structural complexity. Herein, PCM-like polymers (PLPs) with controlled placement of nitrogenous functional groups [i.e., quaternary ammonium (QA), pyridine, and pyridinium cations (py⁺)] were employed as model systems to investigate PCM-enhanced TCP degradation by sulfide. Our results suggest that both PLP-QA and PLP-py⁺ were highly effective …

Type-B Energetic Processes: Their Identification And Implications, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

We have now identified two thermodynamically distinct types (A and B) of energetic processes naturally occurring on Earth. Type-A energy processes, such as classical heat engines, apparently well follow the second law of thermodynamics; Type-B energy processes, such as the newly discovered thermotrophic function that isothermally utilizes environmental heat energy to perform useful work in driving ATP synthesis, follow the first law of thermodynamics (conservation of mass and energy) but do not have to be constrained by the second law, owing to their special asymmetric functions. Several Type-B energy processes such as asymmetric function-gated isothermal electricity production and epicatalysis have …

Calculation Of Elastic Constants Of Bulk Metallic Glasses From Indentation Tests, Zhitong Xu, Ming Liu, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

One of the challenges in the applications of instrumented indentation is to simultaneously measure elastic modulus and Poisson’s ratio of homogeneous, isotropic materials. This work proposes empirical equations for simultaneous calculation of elastic modulus and Poisson’s ratio of bulk metallic glasses (BMGs) from the ratio of the short diagonal length to the long diagonal length and the area of the Knoop imprint. The parameters pre- sented in the empirical equations are determined first by Knoop microhardness tests of 24 BMGs, whose elastic moduli and Poisson’s ratios are measured by resonant ultrasound spectroscopy. These empirical equations are further validated by the …

“Zero” Porosity High Loading Nmc622 Positive Electrodes For Li-Ion Batteries, Haidar Y. Alolaywi, Kubra Uzun, Yang-Tse Cheng

Chemical and Materials Engineering Faculty Publications

LiNi0.6 Mn0.2Co0.2 O 2 (NMC622) is a widely used positive electrode material for lithium-ion batteries, including electric vehicles. In this work, we investigated the effects of porosity, ranging from “zero” to the typical 35%, on the electrochemical behavior of high- loading NMC622 electrodes. Although it is well known that the energy density of the electrode increases with increasing areal capacity and decreasing porosity, NMC-positive electrodes with exceedingly low porosity (e.g., near zero) and high loading (e.g., 4 mAh cm−2 ) have not been investigated. Here, we report an intriguing observation that the “zero porosity” NMC electrode can have higher capacity …

Oxygen Fugacity Of Global Ocean Island Basalts, Lori N. Willhite, Ricardo Arevalo, Philip Piccoli, John C. Lassiter, Devin Rand, Matthew G. Jackson, James M.D. Day, Robert W. Nicklas, Marek Locmelis, Thomas J. Ireland, Igor S. Puchtel

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Mantle plumes contain heterogenous chemical components and sample variable depths of the mantle, enabling glimpses into the compositional structure of Earth's interior. In this study, we evaluated ocean island basalts (OIB) from nine plume locations to provide a global and systematic assessment of the relationship between fO₂ and He-Sr-Nd-Pb-W-Os isotopic compositions. Ocean island basalts from the Pacific (Austral Islands, Hawaii, Mangaia, Samoa, Pitcairn), Atlantic (Azores, Canary Islands, St. Helena), and Indian Oceans (La Réunion) reveal that fO₂ in OIB is heterogeneous both within and among hotspots. Taken together with previous studies, global OIB have elevated and heterogenous fO …

Evaluation Of Novel Preformed Particle Gel System For Conformance Control In Mature Oil Reservoirs, Abdulaziz Almakimi, Ahmed Ben Ali, Ibnelwaleed A. Hussein, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To address challenges associated with excessive water production in mature oil reservoirs, this study introduces a carboxymethyl cellulose (CMC)-based material as a novel preformed particle gel (PPG) designed to plug excessive water pathways and redistribute the subsequent injected water toward unswept zones. Through microwave-assisted grafting copolymerization of CMC with acrylamide (AM), we successfully generated multi-sized dry particles within the range of 250–800 µm. Comprehensive analyses, including Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), have confirmed the chemical composition and morphology of the resulting carboxymethyl cellulose-grafted crosslinked polyacrylamide (CMC/PAMBA). Swelling kinetics and rheology tests were conducted to confirm the …

Mantle Flow And Olivine Fabric Transition In The Myanmar Continental Subduction Zone, Enbo Fan, Yinshuang Ai, Stephen S. Gao, Yumei He, Kelly H. Liu, Mingming Jiang, Guangbing Hou, Shun Yang, Chit Thet Mon, Myo Thant, Kyaing Sein

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

One of the Major Advances in Mineral Physics and Seismology is the Realization that Different Olivine Fabric Types Are Functions of Temperature, Shear Stress, and Water Content in Oceanic Subducting Systems. the Distribution of Different Olivine Fabric Types and Geodynamic Processes in the Mantle Wedge above a Subducting Continental Slab Remain Poorly Understood. Here, based on Splitting Analysis of Shear Waves Recorded by 46 Stations Recently Deployed in Central Myanmar, We Reveal Trench-Perpendicular Fast Orientations between the 80 and 100 Km Slab Contours Sandwiched between Trench-Parallel Fast Orientations from the Mantle Wedge Tip to the Backarc. the Dramatic Change in …

Descriptive Statistical Analysis Of Experimental Data For Wettability Alteration With Smart Water Flooding In Carbonate Reservoirs, Muhammad Ali Buriro, Mingzhen Wei, Baojun Bai, Ya Yao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Smart water flooding is a promising eco-friendly method for enhancing oil recovery in carbonate reservoirs. The optimal salinity and ionic composition of the injected water play a critical role in the success of this method. This study advances the field by employing machine learning and data analytics to streamline the determination of these critical parameters, which are traditionally reliant on time-intensive laboratory work. The primary objectives are to utilize data analytics to examine how smart water flooding influences wettability modification, identify key parameter ranges that notably alter the contact angle, and formulate guidelines and screening criteria for successful lab design. …

Lessons Learned From Laboratory Study And Field Application Of Re-Crosslinkable Preformed Particle Gels Rppg For Conformance Control In Mature Oilfields With Conduits/Fractures/Fracture-Like Channels, Baojun Bai, Thomas P. Schuman, David Smith, Tao Song

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This Paper Surveys the Role of Re-Crosslink able Preformed Particle Gels (RPPG) in Addressing Conformance Challenges within Mature Oilfields. Despite Widespread Preformed Particle Gel (PPG) Application in 15,000+ Wells, their Limitations in Sealing Fractures and Conduits Prevalent in Mature Reservoirs Have Driven the Development of RPPG Formulations. Synthesized in Various Sizes from Micrometer to Millimeter Levels, These Environmentally Friendly RPPGs Are Tailored for Diverse Reservoir Conditions. Findings Showcase the Successful Laboratory-Scale Creation and Upscaling of RPPG Products, Offering Adaptability to Temperatures from 20 to 175°C, Customizable Sizes, Swelling Ratios (5 to 40 Times), and Re-Crosslinking Times Spanning Minutes to Days. …

Electromagnetic Near-Field Scanning With A Spatially Sparse Sampling Strategy Utilizing Kriging-Dmd, Yanming Zhang, Steven Gao, Lijun Jiang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This paper proposes a hybrid method for time-resolved electromagnetic near-field scanning, merging model-based (Gaussian processes regression model, a.k.a. Kriging method) and data-driven (dynamic mode decomposition) techniques. Specifically, Latin hypercube sampling enables spatially sparse measurements, followed by dynamic mode decomposition to analyze resulting sparse spatial-temporal data, extracting frequency information and sparse dynamic modes. The Kriging method is then employed for full-state reconstruction. The proposed approach is evaluated using crossed dipole antennas. Results indicate that, even with a spatial subsampling factor of 130, achieving a fully reconstructed field distribution suitable for engineering applications with frequency information extraction is feasible. This hybrid framework …

Improving Insar Accuracy For Slow Deformation And Change Detection With Lidar And Gps, Yusupujiang Aimaiti, Vasit Sagan, Cagri Gul, Jeremy Maurer, Jackson D. Cothren, Carla Klehm, Elizabeth A. Koenig, Nathan Scott

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Interferometric Synthetic Aperture Radar (InSAR) uses two or more SAR images over the same region for mapping ground surface displacements through time. InSAR displacements are relative to a reference point due to the 2π phase ambiguity that from unwrapping, and as a result ground control points (GCPs) are often used to calibrate the displacement model and obtain absolute measurements. Errors in InSAR time-series are typically measured with respect to the reference point, but absolute errors are not currently well constrained. To develop absolute error models for InSAR, we generate Sentinel-1 InSAR time-series for Belleville, Illinois and compare time-series with Global …

Borate-Based Bioactive Glasses Properties: Clinical And Biomedical Applications, Sarah Fakher, David J. Westenberg

Biological Sciences Faculty Research & Creative Works

Borate bioactive glasses (BBGs) constitute the recently produced bioactive glasses (BGs) in the domain of bioactive materials, offering enhanced functionalities over conventional silicate and phosphate BGs. This advancement is primarily characterized by BBGs' rapid yet controllable degradation rates, superior bioactivity, and the ability to swiftly form a hydroxyapatite layer (HAP) upon interaction with physiological fluids. A distinguishing feature of BBGs lies in their customizability; doping with therapeutic metal ions tailors their bioactivity towards specific physiological responses, including promoting angiogenesis, antibacterial activity, and osteogenesis. This versatility of BBGs' applications extends to bone regeneration, wound healing, drug delivery systems, and potentially nerve …

Developing Smart Textiles Encapsulated With Single Walled Carbon Nanotubes For Biomedical Applications, Devleena Chowdhury

Open Access Master's Theses

This thesis investigates the creation of core-shell nanofibers for enhanced wound healing applications using a variety of polymer combinations. Chronic wounds are a major worry in the biomedical sector, and researchers are looking at new materials to help the healing process. The PVDF/PVA core-shell structure with single-walled carbon nanotubes (SWCNTs) was chosen due to its balanced mechanical strength, high biocompatibility, and DNA-SWCNT complex stability. PVDF is a preferred shell material due to its biocompatibility and water solubility, making it excellent for wound dressings, implanted scaffolds, and sensors that monitor healing.

The study focuses on improving the electrospinning method to produce …

Beneficiation Of Lunar Regolith Simulants Through Electrostatic Sieving And Magnetic Separation, Peter Bachle, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

In the light of future development of lunar structures, in-situ feldspar beneficiation is imperative for metal extraction. This research incorporates the tandem use of electrostatic sieving and magnetic separation for collecting a specific size range and mineral composition from lunar soil that optimizes subsequent chemical processing. While earlier works focused on silt-sized particles, this work expands that range up to medium-grained sand with a greater variety of potential lunar regolith compositions. This work shows that a 2.5 kV, 7 Hz to 30Hz frequency, single-phase square wave can lift silt and fine sand for collection. This lifting is successful directly from …