Technological And Mechanical Properties Of Polyethylene Filled With Nano-Sized Calcium Carbonate,
2025
«Shurtan Gas Chemical Complex» LLC, Guzar, Uzbekistan
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,
2025
Tashkent Institute of Chemical Technology, Tashkent, Uzbekistan
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,
2025
Tashkent Institute of Chemical Technology
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,
2025
Missouri University of Science and Technology
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,
2025
University of Southern Mississippi
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. …
Influence Of Mixing Duration And Absorption Characteristics Of Superabsorbent Polymers On The Fresh And Hardened Properties Of High-Performance Concrete,
2025
Missouri University of Science and Technology
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 …
Investigation Of Solid-State Reactive Sintering And Rapid Laser Reactive Sintering For Al-Doped Li7la3zr2o12 Solid-State Electrolyte,
2025
Clemson University
Investigation Of Solid-State Reactive Sintering And Rapid Laser Reactive Sintering For Al-Doped Li7la3zr2o12 Solid-State Electrolyte, Aaron Santomauro
All Dissertations
As a society, we’ve exhausted an extreme amount of fossil fuels and put an overwhelming strain on Earth’s natural resources. From this, it is critical to think about the successful future of our planet and ourselves by developing energy devices such as all-solid-state lithium-ion batteries (ASSLIBs). These devices offer a greener and more efficient alternative to power our daily lives, such as electric vehicles (EVs), portable electronics, medical devices, grid-scale energy storage, and aerospace/aviation. ASSLIBs are an excellent alternative to liquid-state batteries, which pose dangerous safety concerns (e.g., flammability, electrolyte leakage, etc.). These ASSLIBs are known to have generally high …
Hardware And Software Design For A Portable Surgical Training Simulator,
2025
University of Nebraska-Lincoln
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 …
Controlling Electroless Deposition On Polymer Interfaces Towards Discrete Functional Particle Synthesis,
2025
University of Arkansas-Fayetteville
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,
2025
Clemson University
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 …
Advancing Lithium-Ion Batteries Through Exploration Of Novel Physico-Chemical Phenomena,
2025
Clemson University
Advancing Lithium-Ion Batteries Through Exploration Of Novel Physico-Chemical Phenomena, Peshal Karki
All Dissertations
Lithium-ion batteries (LIBs) power a wide range of modern devices, from smartphones to electric vehicles. This dissertation integrates materials characterization and electrochemical testing to develop novel Si-based electrode materials, investigate separator effects, and improve electrochemical impedance spectroscopy (EIS) modeling. First, I synthesized Si@CC composites using bio-based carbon sources and discovered a novel in situ disorder reduction in the amorphous carbon cloud during cycling, attributed to Si volume fluctuations and mesoporous carbon structure, which enhanced capacity retention. A binder-free electrode (Si@CC@BP) using bucky paper further improved gravimetric and areal capacities while reducing weight and manufacturing complexity.
Next, I investigated how separator …
Crevice Corrosion Mechanisms Of Cocrmo Alloys In Orthopedic Implants: Retrieval Analysis, Nano-Tribocorrosion And Cellular Responses,
2025
Clemson University
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,
2025
Clemson University
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 …
Ferroelectricity And Multiferroicity In Ultrathin Films Of Unconventional Transition Metal Oxide,
2025
University of Nebraska-Lincoln
Ferroelectricity And Multiferroicity In Ultrathin Films Of Unconventional Transition Metal Oxide, Xin Li
Department of Physics and Astronomy: Dissertations, Theses, and Student Research
Ferroic orders of transition metal oxides, such as ferroelectricity and ferromagnetism, are determined by the intercoupling between spin, charge, lattice. Consequently, ferroic epitaxial thin films have attracted wide interest due to the profuse novel phenomena and the great application potentials for modern electronics. However, the mainstream of the study for transition metal oxides has focused on perovskite structure, limiting the understanding and discovery of novel phenomena associate with ferroic orders. In this thesis, the epitaxial films of hexagonal rare-earth ferrites (h-RFeO3) and fluorite-structure hafnia oxide (HfO2) are studied comprehensively, providing new experimental and theoretic …
Polymer-Enhanced Nanopore Sensing,
2025
University of Arkansas-Fayetteville
Polymer-Enhanced Nanopore Sensing, Eugene Gyasi Agyemang
Graduate Theses and Dissertations
The resistive pulse technique characterizes single analytes by detecting fluctuations in the ion current as they pass through a narrow orifice connecting two electrolyte-filled chambers, each containing a single electrode. The amplitude, shape, frequency, and duration of these fluctuations primarily provide information about the analyte’s size, shape, concentration, and net surface charge, respectively. One configuration for resistive pulse measurements is of an electrolyte-filled nanopipette immersed in a bath, where the nanopipette tip acts as the nanoscale orifice. It was previously shown that incorporating the large quantities polymer polyethylene glycol (PEG 8K, 50% w/v) into the external electrolyte bath dramatically enhanced …
Enhancing The Design Of Strained Superlattice Gallium Arsenide Based Photocathodes With Distributed Bragg Reflector,
2025
Old Dominion University
Enhancing The Design Of Strained Superlattice Gallium Arsenide Based Photocathodes With Distributed Bragg Reflector, Adam D. A. Masters
Electrical & Computer Engineering Theses & Dissertations
Particle accelerators play a crucial role in our understanding of matter and the universe and have numerous practical applications in various fields. These devices enable scientists to examine the smallest components of matter, study the forces that govern their interactions, and probe conditions from the early universe. Moreover, accelerators are valuable in medicine, industry, and research, enhancing imaging methods, cancer therapies, and manufacturing techniques. As the experiments conducted at these facilities evolve and require higher precision, improved particle sources must continue to advance to keep up with their requirements. To do that, we enhanced the design of spin polarized electron …
A Strict Physicality-Preserving Scheme For A 2d Q-Tensor Flow With A Singular Potential,
2025
Old Dominion University
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 …
Two Analytic Issues Arising From Models In Probability And Materials Science,
2025
Old Dominion University
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 …
Feasibility Study On Using Blue Clay As A Supplementary Cementitious Material (Scm).,
2025
University of Louisville
Feasibility Study On Using Blue Clay As A Supplementary Cementitious Material (Scm)., Clark Lemon
Master of Engineering Theses
An effective strategy for reducing CO2 emissions in the global cement industry is replacing a percentage of cement with supplementary cementitious materials (SCMs). As the availability of conventional SCMs such as fly ash and slag is decreasing, alternative SCMs such as calcined clays have been studied for their use as effective pozzolans. The present work investigates the feasibility of using a waste product from the quarrying industry known as blue clay as a viable SCM. It is composed of multiple clay minerals, predominantly muscovite. Raw and calcined at four temperatures (500, 650, 800, and 950°C), blue clay was analyzed …
Shape Memory Behavior In Medium To High Entropy Shape Memory Alloys: Design, Prediction, And Experimental Analysis,
2025
Florida Institute of Technology
Shape Memory Behavior In Medium To High Entropy Shape Memory Alloys: Design, Prediction, And Experimental Analysis, Hatim Raji
Theses and Dissertations
This dissertation provides a data-driven system integrating synthetic data generation and machine learning (ML) techniques to create multicomponent SMA compositions with specific transformation temperatures (TTs). Models were trained to represent the nonlinear dependencies influencing martensitic transformation behavior by using elemental, thermodynamic, and process-related aspects. The capacity of the ML models on medium entropy NiTiHfPd and high entropy NiTiHfZrCu systems accuracy was confirmed by experimental validation showing TTs closely matched with model outputs.
