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Functional Biopolymers Applied To Sustainable Technologies In The Environment And Healthcare, Fengjie He

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biodegradable polymeric materials (biopolymers) are naturally derived materials known for their excellent biocompatibility, biodegradability, sustainability, and versatile chemical functionality. They have attracted increasing attention in various applications as alternative to synthetic materials ranging from food packaging to tissue engineering. Meanwhile, with intrinsic advantages, biopolymers have also emerged as promising materials in addressing contemporary challenges in both biomedical and environmental fields. Motivated by the significant potential of biopolymers and the growing need for sustainable materials, my research focuses on the design and engineering of biodegradable polymers with novel modification methods and application directions. In this work, two representative biopolymers are selected: …

Bio-Inspired Electroactive Polymer (Eap) Sensors For Surface And Canal Flow Sensing In Dynamic Environments, Nazanin Minaian

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nature can often create some of the most efficient and elegant solutions to complex problems, and engineering stands to benefit greatly from these time-tested designs. One of the more sophisticated examples of this is the lateral line system in fish: a distributed network of superficial and canal neuromasts that enables aquatic species to detect fluid disturbances with remarkable precision. This dissertation leverages that biological framework to explore the potential of electroactive polymers (EAPs), aiming not just to replicate structure, but to emulate function.Two classes of EAPs form the basis of this work: electroactive plasticized polymer gels (EPPGs) and ionic polymer-metal …

Development Of Construction Materials With Natural Fibers And Flax Shives For Green Eco-Friendly Buildings. Mrs Advances (2025), Iman El-Mahallawi, Lamiaa Mohamed, Rania El‑Shorbagy, Mahmoud Tash, Aliaa Abdelfatah

Mechanical Engineering

Sustainability-oriented solutions are essential to address the depletion of natural resources, solid waste accumulation, and high CO2 emissions in the construction industry. This research focuses on the development of environmentally friendly green bricks by replacing high-carbon-footprint constituents with local, natural materials. Specifically, flax shives, a natural agricultural by-product, and marble powder, an industrial waste, were used as partial substitutes in the binder matrix. The natural fibers not only promote sustainability but also enhance insulation and reduce the environmental burden. The bricks were molded into rectangular specimens (60 × 100 × 200 mm) and tested for thermal conductivity, moisture absorption, and …

Development And Optimization Of Gradient Pore Structured Porous Ceramics: Modeling, Properties, And Potential For Industrial Production In Thermal Insulation Engineering, Gang Qi, Minghui Li, Ruoyu Chen, Haichuan Wang, Haiming Wen, Yi Ding, Xiaoyu Xia, Dixin Yan, Can Chen, Saisai Li

Materials Science and Engineering Faculty Research & Creative Works

This study prepared gradient pore structure ceramics from silica fume through direct foaming. The rheological behavior of the slurry was improved by varying the solids content. Physical and mathematical models were developed to describe the longitudinal movement of foam in the ceramic slurry and the mechanism of gradient pore formation. These models were used to predict the pore sizes at different heights within the ceramic. Insulation and mechanical properties were enhanced by optimizing the gradient pore structure. The gradient pore structure resulted in significant directional differences in specimen properties. Additionally, suitable sintering-temperatures for gradient pore structure ceramics are discussed. The …

Wear Of High Entropy Alloys: Understanding Effects Of Cryogenic Temperatures And Surface Nitriding On Wear Behavior, Aubrey Yu Tang

Dartmouth College Ph.D Dissertations

Cryogenic tribological applications have become increasingly important with the development and innovation of advanced equipment in aerospace, polar regions, superconductivity, and more. Traditional lubrication methods are not viable under these harsh environments, so metallic materials must be able to maintain excellent mechanical properties and withstand the constant impact and wear alone. High entropy alloys (HEAs) have emerged as potential candidates for these applications because of their wide variety of excellent room temperature properties and apparent improvement of mechanical properties of some HEAs at extremely low temperatures. Despite their promising nature, very limited work has been done on understanding the wear …

64th Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 64th annual meeting of the Rocky Mountain Conference on Magnetic Resonance. Held in the Snowbird Resort and Conference Center, Snowbird, Utah, August 3-7, 2025.

Transformations Of Uzbekistan Quartz Raw Materials – Quartzites Of The Dzherdanak Deposit And Vein Quartz Of The Nurota Deposit Under Thermal Impact, Umar G. Nomazov, Mastura Kh. Aripova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work is to study the transformations of quartz raw materials as a result of high-temperature exposure. The objects of the study were quartzite from the Dzherdanak deposit in the Surkhandarya region and vein quartz from the Nurota deposit in the Samarkand region. The mineralogical composition of natural raw materials and phase and structural transformations during high-temperature exposure to 1430 ° C were studied using X-ray and differential thermal analysis. Based on the results of physicochemical analysis methods, it was found that vein quartz consists entirely of quartz and, therefore, it can be assumed that impurity elements …

Kinetics Of Adsorption Of Copper And Nickel Ions Using A Rice Husk-Based Sorbent, Aziza A. Maksudova, Shukhrat A. Mutalov, Klara M. Adilova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this study is to investigate the adsorption kinetics of Cu(II) and Ni(II) ions from aqueous solutions using an adsorbent obtained by treating rice husk with a solution of monoethanolamine. The experiments evaluated the influence of contact time on the efficiency of metal ion removal and calculated the adsorption capacity. To analyze the adsorption process kinetics, pseudo-first-order and pseudo-second-order kinetic models were applied. The results demonstrated that the adsorption process follows the pseudo-second-order kinetic model. Thus, monoethanolamine-modified rice husk can be considered an effective, environmentally friendly, and economically viable sorbent for the removal of heavy metal ions from …

Quantum-Chemical Study Of Complex Compounds Of Lanthanides With 2-Aminobenzimidazole Derivatives, Bakhtigul Yu. Ruzieva, Feruza F. Fayzullayeva, Zuhra Ch. Kadirova, Shahlo Sh. Daminova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this study is to perform quantum-chemical modeling of mixed-ligand complexes of trivalent lanthanoid ions (Ln³⁺) involving primary ligands — 2-amino-1-methylbenzimidazole (MAB) and 2-phenylmethyl-1H-benzimidazole (FAB), as well as additional ligands — diethyldithiocarbamate (DEDTK), benzohydroxamic acid (BGK), and potassium diisopropyldithiophosphate (DiPDTP). Quantum-chemical calculations were carried out using semi-empirical methods within the PM3 and PM6 approaches, implemented in the BIOVIA Materials Studio (Accelrys Studio 2017) software package. The obtained data made it possible to determine the influence of the nature of the mixed ligands on the coordination behavior of lanthanoids and the stability of the corresponding complexes.

Synthesis And Ir Spectroscopic Study Of Complexes Of Selected 3d-Metals With 2-(Phenylmethyl)-1h-Benzimidazole, Gulnoza O. Babayeva, Gulbeka G. Mamatova, Daminbek A. Ziyatov, Lola Sh. Makhmudova, Shahlo Sh. Daminova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this study was the synthesis and structural investigation of coordination compounds of selected 3d-metals with 2-(phenylmethyl)-1H-benzimidazole (FAB) using IR spectroscopy. Complexes of copper(II), nickel(II), cobalt(II), and zinc(II) with the general formula [M(FAB)₂Cl₂], as well as a complex [Co(FAB)₂(ac)₂], were synthesized. IR spectroscopic analysis revealed that FAB coordinates to metal ions through the nitrogen atom of the benzimidazole ring. Shifts in the ν(C=N), ν(C-N) bands and the appearance of new bands in the 580-430 cm⁻¹ region corresponding to ν(M-N) and ν(M-Cl) confirm the formation of metal complexes. It was established …

Technological And Mechanical Properties Of Polyethylene Filled With Nano-Sized Calcium Carbonate, Ilyos M. Makhmudov, Ravshan I. Adilov, Muzafar G. Alimukhamedov, Farangiz B. Izzatullayeva

CHEMISTRY AND CHEMICAL ENGINEERING

Currently, one of the most effective and cost-effective ways to modify the properties of polyethylene is to introduce various fillers of organic or inorganic origin. The purpose of this work was to study the effect of the concentration of nanosized calcium carbonate on the technological and physicomechanical properties of polyethylenes of various origins. In the work, we used two grades of polyethylene: HDPE (273-83) and LDPE (10803-020) produced by Kazanorgsintez OJSC. The following were used as nanofillers: nanosized calcium carbonate in the form of a compound of the Nano-cal NC-K0117 brand made in China. The dependence of the physicomechanical properties …

Additional Loss On Ignition Of Cement Raw Mixes At High Temperatures, Geun-Seong Lee, Farrukh B. Erkinov, Mastura Kh. Aripova

CHEMISTRY AND CHEMICAL ENGINEERING

Loss on ignition (LOI) of cement, raw materials and raw mixes in cement industry is specified as the weight loss at 900~1000 ^oC and 15~30 minutes in the standards of each region (GOST, ISO, ASTM, JIS, KS) in the world, and the clinker yield produced from the raw mixes feeding to the kiln process is generally derived from the LOI. The kiln conditions are significantly different from those specified in the standards, because the material temperature is up to 1450 ^oC and the residence time is about 15 minutes above 1000 ^oC in the kiln burning process. …

Composition Of Porcelain Mass Based On Clay Shale From The Dzherdanak Deposit, Ripsime V. Mkrtchyan

CHEMISTRY AND CHEMICAL ENGINEERING

Known sources of high-quality raw materials are depleted. To meet the growing demand for porcelain products, natural raw materials from new deposits are being studied. The aim of the study is to develop a composition of porcelain mass for household porcelain based on unconventional raw materials - clay shales of the Dzherdanak deposit. Compositions of hard porcelain based on clay shales and other components of local natural raw materials with and without magnesium oxide have been developed. As a result of X-ray and electron microscopic studies of the porcelain structure, it was determined that the crystalline phases in the porcelain …

Solvent- And Binder-Free Additive Manufacturing Of Polymer-Derived Ceramics: Rheological Tuning And Structural Performance, Laxmi Sai Viswanadha, Jeremy Watts, Mohammad Naraghi

Materials Science and Engineering Faculty Research & Creative Works

Silicon carbide (SiC) ceramic matrix composites are widely used in aerospace applications due to their high strength, heat resistance, and corrosion resistance. However, traditional machining methods make it challenging to fabricate complex shapes. This study presents a solvent-free and binder-free direct ink writing (DIW) method for producing SiC/SiOC composites using polycarbosilane SMP-10, a preceramic polymer that acts as both the ceramic precursor and the liquid phase, thereby eliminating the need for volatile solvents and sacrificial binders. By adjusting the SiC content, printable ink formulations were developed, and their flow properties were analyzed. The influence of geometric factors, such as inter-wall …

Understanding Structure-Property Relationships Within Polyolefin-Derived Vitrimer Systems, Mikaela Sadri

Dissertations

Polyolefins are extremely ubiquitous materials due to their satisfactory material properties, ease of synthesis, and low cost. Unfortunately, their extensive use has led to a global plastic waste mismanagement problem. As such, notable efforts have recently focused on converting these commodity polymers into vitrimers, or dynamic networks, to extend their use-life and tailor their properties. However, the fundamental polymer physics of these emerging materials, remain largely underexplored, hindering their widespread implementation. To address this challenge and enable a more sustainable future, the overarching goal of my dissertation research is to understand the fundamental structure-property relationships within complex polyolefin-derived vitrimer systems. …

Impact Of Humidity From Shrink (Wrap) Tunnels On Refrigeration Systems: Comparing Economic And Environmental Impact Of Natural Gas And Electric, Segun Samuel Oladipo

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This thesis examines the economic and environmental effects of electric and steam shrink-wrapping tunnels used in beef packaging processes, paying particular attention to the indirect refrigeration loads caused by the heat and humidity that each system releases. Traditional sustainability evaluations frequently ignore these indirect impacts, which are especially important in meat processing facilities where 45–55% of electricity use is attributed to refrigeration. Life cycle assessment (LCA), field measurements, and thermodynamic modeling are all used in this work to offer a thorough analysis of both tunnel types.

The case study facility in Nebraska operates both steam and electric shrink tunnels to …

Hardware And Software Design For A Portable Surgical Training Simulator, Victoria Nelson

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

More than 51 million surgeries are performed on patients annually in the United States. That number grows to 310 million surgeries performed globally each year. Most surgeons go through a minimum of five years of residency – where they train and hone their surgical skills. It is important during this time, and throughout their careers, that they get plenty of practice. Surgical training is time intensive, expensive, and frequently under-resourced. There are finite amounts of surgical training modules for students to share at their facilities. The problem of getting adequate surgical training time continues to exist after surgeons begin their …

Grain Boundary Migration And Radiation Induced Segregation In Fe-Cr Alloys, Mohit Dhoriya

All Theses

Radiation-induced segregation (RIS) is a significant phenomenon that occurs in alloys subjected to irradiation, particularly in environments such as nuclear reactors. This thesis investigates RIS in ferritic Fe- Cr alloys through the use of Atomic Kinetic Monte Carlo (AKMC) simulations, focusing on the interaction between solute atoms and migrating grain boundaries. The study explores the influence of temperature, solute concentration, and grain boundary velocity on solute drag, a critical process driving RIS. The results show that solute migration is strongly influenced by the presence of vacancies and interstitials generated under irradiation, which are absorbed by grain boundaries and other defect …

Advancing Multi-Physics Modeling For Microwave Heating: Application In Micro-Reactor Design And Optimization, Raghav Adhikari

All Theses

Microreactors are a type of small-scale chemical reactors for achieving reduced volume, improved product selectivity and higher reaction rate. It allows precise temperature control, which is crucial for sensitive chemical processes. Microreactors can be employed as key components of conducting small-scale reactions with improved reactor configuration and process efficiency. It is important to identify a localized and precise heating mechanism to trigger and control the corresponding chemical reactions.

In fact, microwave heating has gathered significant attention in recent years due to its ability to deliver efficient, rapid, and localized heating, which can accelerate reaction rates and enhances the reaction selectivity. …

Controlling Electroless Deposition On Polymer Interfaces Towards Discrete Functional Particle Synthesis, Grecia Pierina Alvarado Munoz

Graduate Theses and Dissertations

Electroless deposition is a process that facilitates the formation of metal layers on surfaces through the reduction of metal ions onto a surface in the presence of a sacrificial reducing agent. This process can be applied to synthesize conductive metal layers on insulators such as glass or polymers. The kinetics of heterogeneous deposition depend on the interfacial surface chemistry, including the presence of added catalyst materials, as well as the bulk chemical environment, such as the concentration of metal ions and sacrificial reductants. Furthermore, the homogeneous formation of metal nanoparticles may compete with the deposition reaction, adversely affecting the control …

Discovery Of High-Performance Cathode Materials For Protonic Ceramic Fuel Cells, Liang Han

All Dissertations

Environmental pollution and rapid energy consumption have become common problems in global development and will continue to grow with the world population. PCFCs use proton-conducting ceramics as electrolytes, with low activation energy and high ionic conductivity at intermediate temperatures, enabling them to operate at intermediate-temperature conditions, which can effectively solve the problems of poor stability and high cost of exotic materials of traditional solid oxide fuel cells. However, as the operating temperature decreases, the electrocatalytic activity of the cathode decreases significantly, seriously affecting PCFC’s performance. Therefore, developing high-performance cathode material suitable for working under intermediate-temperature conditions has become the key …

Considerations For Developing Dna-Templated Dye-Aggregate Systems, Simon Kristopher Roy

Boise State University Theses and Dissertations

Molecular excitons have been the subject of significant research interest for nearly 100 years. Molecular excitons arise when conjugated organic molecules (dyes) are excited such that the resulting excitation is delocalized over multiple dyes in a wavelike manner. The shared excited states that allow the excitation energy to hop between molecules is of particular interest for applications that can make use of the wavelike properties of excitons, including applications in quantum information science. A key challenge for developing materials for these advanced applications is to overcome the knowledge gaps associated with precisely templating dyes with spatial control of their aggregation, …

Crevice Corrosion Mechanisms Of Cocrmo Alloys In Orthopedic Implants: Retrieval Analysis, Nano-Tribocorrosion And Cellular Responses, Hwaran Lee

All Dissertations

Mechanically assisted corrosion and non-mechanically (chemically) driven corrosion in modular junctions of orthopedic implants using cobalt-chromium-molybdenum (CoCrMo) alloys remain clinical concerns and may contribute to implant failure. The underlying corrosion mechanisms are not yet fully understood, leaving a critical research gap. We hypothesized that corrosion in modular junctions may be driven by aggressive local environments, including fretting, metal ion release (cobalt ion, Co²⁺), low pH and reactive oxygen species (ROS). This dissertation aims to (1) analyze corrosion modes and potential causes in modular junctions; (2) identify chemically driven corrosion modes on CoCrMo alloys using simulated inflammatory modular taper …

Self-Poled P(Vdf-Trfe) Based Composites For Energy Harvesting And Wearable Sensor Applications, Lavanya Muthusamy

All Dissertations

The growing demand for flexible, low-power, and self-powered wearable electronic systems has accelerated research interest in polymer-based sensors and energy harvesting technologies. Among piezoelectric polymer materials, Poly(vinylidene fluoride-trifluoro ethylene) [P(VDF-TrFE)], over the years, has garnered significant attention due to its unique piezoelectric properties, high dielectric constant, mechanical flexibility, thermal stability, chemical resistance, biocompatibility and compatibility with scalable fabrication processes. Despite its advantages, conventional P(VDF-TrFE)-based devices often require external poling and face limitations in integration with low-cost, flexible substrates. To overcome these limitations, this research study explores the nanofiller approach, along with facile fabrication processes, and structural design strategies aimed at …

Integration Of Highly Mismatched Iii-Sb Virtual Substrates On Silicon Via Interfacial Misfit Arrays For Short-, Mid-, And Long-Wave Infrared Applications, Trent Garrett

Boise State University Theses and Dissertations

Lattice constants of the III-V semiconductors range from 5.45 Å (GaP) to 6.48 Å (InSb). III-V semiconductors are grown on commercially available substrates made from binary III-V materials (e.g., GaAs, InP, and GaSb), or group IV materials (e.g., Si or Ge). These substrates offer very high quality, but only offer access to a small number of specific lattice constants. Given this constraint, it is desirable to develop growth methods that would allow the grower to modulate from the substrate lattice constant into the lattice constant of the material structure under investigation.

Device structures made from III-V semiconductors lattice-mismatched to these …

Development Of A Wearable Biosensor For Cortisol Detection In Human Sweat Utilizing Pani/Peo Polymer Blend And Nitrogen-Doped Graphene Quantum Dots, Cesar Sanchez

Theses and Dissertations

Since the development of the first biosensor in 1962, the evolution of commercially available wearable biosensors has been driven by an increasing consumer interest in real-time health tracking. However, challenges related to sensor sensitivity and cost have hindered progress. Deploying a novel approach, the biosensor integrates a blend of Polyaniline (PANi) and Polyethylene Oxide (PEO) along with Nitrogen-doped Graphene Quantum Dots (N-GQDs) to enhance sensitivity and electroactivity, crucial for cortisol detection. To optimize performance, three distinct synthesis methods for N-GQDs; hydrothermal, microwave, and hot plate synthesis were compared employing a bottom-up approach utilizing citric acid (CA) as the primary reactant …

Two Analytic Issues Arising From Models In Probability And Materials Science, Giang Vu Thanh Nguyen

Mathematics & Statistics Theses & Dissertations

This dissertation explores two distinct topics centered on mathematical models in probability theory and materials science. The first part investigates a series of functions derived from an adaptive algorithm designed to address the score-based secretary problem, a classic challenge in probability theory. This problem involves making immediate decisions to select the best candidate from a sequence of interviews. The algorithm aims to maximize the probability of selecting the optimal candidate based on observed scores. We prove two fundamental analytic properties of this sequence of functions as a theoretic support of the algorithm: first, the functions in the sequence each possess …

Towards Improving Computational Modeling Of The Lumbar Spine - Impact Of Material Properties And Laminotomy On Spinal Biomechanics, Isaac K. Kumi

Mechanical & Aerospace Engineering Theses & Dissertations

Spinal ligaments play a crucial role in maintaining the mechanical stability of the lumbar spine. These dense, collagenous tissues not only resist excessive motion but also distribute loads between spinal components to protect neural structures. Traditionally, the mechanical response of ligaments has been modeled using linear elastic assumptions, which treat the tissue as having a constant stiffness regardless of loading history. While this simplifies analysis, it fails to capture the time-dependent behaviors, such as creep, stress relaxation, and hysteresis, that are characteristic of biological tissues.

Viscoelastic modeling may provide a more physiologically accurate representation by incorporating both elastic and viscous …

A Strict Physicality-Preserving Scheme For A 2d Q-Tensor Flow With A Singular Potential, Md Mashud Parvez

Mathematics & Statistics Theses & Dissertations

Nematic liquid crystals are a state of matter that exhibit properties between those of conventional liquids and solid crystals. Their unique ability to align molecules in specific directions makes them essential in various applications, including display technologies and advanced materials. To model their complex behavior, mathematical frameworks such as the Q-tensor model are used to describe the orientation and degree of molecular order. In this work, we introduce a numerical scheme for a two-dimensional (2D) dynamic Q-tensor model, which is formulated as an L²-gradient flow driven by the liquid crystal free energy and incorporates a singular potential to …

Influence Of Mixing Duration And Absorption Characteristics Of Superabsorbent Polymers On The Fresh And Hardened Properties Of High-Performance Concrete, Yu Cun Gu, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the combined influence of superabsorbent polymers (SAPs) with distinct absorption kinetics and extended mixing sequences on the rheological, mechanical, and transport properties of high-performance concrete (HPC). Two SAPs—an ionic acrylamide-co-acrylic acid copolymer (SAP-P) and a non-ionic acrylamide polymer (SAP-B)—were incorporated at an internal curing level of 100%. The impact of extended mixing times (3, 5, and 7 min) following SAP addition was systematically evaluated. Results showed that longer mixing durations led to increased superplasticizer demand and higher plastic viscosity due to continued water absorption by SAPs. However, yield stress remained relatively stable owing to the dispersing effect …