Supported Metal Nanoparticle Synthesis: Precursor Deposition And Agglomeration At Support Surfaces,
2024
Virginia Commonwealth University
Supported Metal Nanoparticle Synthesis: Precursor Deposition And Agglomeration At Support Surfaces, Edward H. Chandler Jr.
Theses and Dissertations
Catalysis is a critical component of the chemical manufacturing industry. For example, it has been estimated to be essential to more than 90% of the major industrial processes developed during the middle years of the 20th century.1 Heterogeneously supported transition metal catalysts in particular have many benefits such as easy separability from the reaction mixture and high thermal stability. One method of synthesizing these is wet impregnation, wherein a metal solution is brought into contact with an oxide- or carbon-based powder. Given optimal environmental conditions, a metal will adhere to the surface through electrostatic means in a process …
Developing Machine Learning And Time-Series Analysis Methods With Applications In Diverse Fields,
2024
Virginia Commonwealth University
Developing Machine Learning And Time-Series Analysis Methods With Applications In Diverse Fields, Muhammed Aljifri
Theses and Dissertations
This dissertation introduces methodologies that combine machine learning models with time-series analysis to tackle data analysis challenges in varied fields. The first study enhances the traditional cumulative sum control charts with machine learning models to leverage their predictive power for better detection of process shifts, applying this advanced control chart to monitor hospital readmission rates. The second project develops multi-layer models for predicting chemical concentrations from ultraviolet-visible spectroscopy data, specifically addressing the challenge of analyzing chemicals with a wide range of concentrations. The third study presents a new method for detecting multiple changepoints in autocorrelated ordinal time series, using the …
Kinetic Modeling Of Electrostatic Sieving For Lunar Regolith Beneficiation: Case Studies,
2024
Missouri University of Science and Technology
Kinetic Modeling Of Electrostatic Sieving For Lunar Regolith Beneficiation: Case Studies, Easton Ingram, Emmanuela Amen Eze, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han
Materials Science and Engineering Faculty Research & Creative Works
A new kinetic particle modeling framework was developed to investigate electrostatic transport of lunar regolith particles with applications to the concept of electrostatic sieving. the new approach is based on kinetic particle dynamics and includes major modules of sampling the particle size distribution, solving electric fields, and tracking motion of charged dust grains. Case studies for a concept of electrostatic sieving were chosen to validate the new model. the simulation achieved similar yields reported in previous works, which served as validation of the model. the new model is computationally efficient and could serve as a design, analysis, and optimization tool.
Progress Of Lisap-Mse: A Concept Of Producing Aluminum In-Situ On The Moon Through Molten Salt Electrolysis,
2024
Missouri University of Science and Technology
Progress Of Lisap-Mse: A Concept Of Producing Aluminum In-Situ On The Moon Through Molten Salt Electrolysis, Jacob N. Ortega, David Bayless, Daniel Stutts, Daoru Han, Todd P. Sander, Jeffrey Smith, Fateme Rezaei, William Schonberg
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This paper presents a concept of producing aluminum in-situ on the lunar surface, namely, the Lunar In-Situ Aluminum Production through Molten Salt Electrolysis (LISAP-MSE) method developed at Missouri University of Science and Technology. This paper aims to demonstrate the use of electro-deoxidation to reduce aluminum oxide (i.e., alumina) into aluminum and oxygen gas via electrolysis in a molten salt bath for the production of aluminum on the Moon. It is shown that with a steady supply of hydrogen chloride, this in-situ resource utilization (ISRU) method could supply several necessary materials consumed in the electro-deoxidation process except hydrogen chloride to produce …
Sustainable Cementitious Materials For Building And Sorption Applications,
2024
Missouri University of Science and Technology
Sustainable Cementitious Materials For Building And Sorption Applications, Sukanta Kumar Mondal
Doctoral Dissertations
"Ordinary Portland Cement (OPC) is the most widely used cement material, but it contributes over 8% of the global CO2 emission and the process is energy intensive. Moreover, OPC faces durability challenges, particularly in aggressive environments. Hence, there is rapidly increasing interest in sustainable alternative cements with lower carbon footprint, lower energy consumption, and those that offer superior properties that are beneficial for specific applications. Two sustainable cementitious materials that are frequently researched as an alternative to OPC are calcium sulfoaluminate (CSA) cement and alkali-activated materials (AAMs). CSA cement lowers CO2 emission by over 40% compared to OPC, …
Investigations Of Performance And Emissions Of A Fischer-Tropsch Gtl Sustainable Aerospace Fuel With Lubricity Improver In A Compression Ignition Engine With Butanol Port Fuel Injection,
2024
Georgia Southern University
Investigations Of Performance And Emissions Of A Fischer-Tropsch Gtl Sustainable Aerospace Fuel With Lubricity Improver In A Compression Ignition Engine With Butanol Port Fuel Injection, James B. Willis
College of Graduate Studies: Theses & Dissertations
As there is increasing concern over emissions of traditional fossil fuels, as well as the future of continued reliance on this dwindling resource, it is becoming increasingly evident that alternative fuels are a necessity. This research investigates the use of a Fischer-Tropsch fuel from natural gas feedstocks, S8, in an internal combustion research engine with a common rail fuel injection system. This synthetic kerosene fuel has a high DCN of 62, indicating high affinity to autoignition compared to conventional pump diesel (ULSD) at 48 DCN. However, due to the process by which it is produced, this fuel lacks the necessary …
Investigation Of Asphaltene Instability Under Gas Injection In Unconventional Reservoirs And Its Impact On Oil Recovery Performance,
2024
Missouri University of Science and Technology
Investigation Of Asphaltene Instability Under Gas Injection In Unconventional Reservoirs And Its Impact On Oil Recovery Performance, Mukhtar Elturki
Doctoral Dissertations
"Unconventional reservoirs, such as shale gas and tight oil formations, have become an important source of energy in recent years. However, these reservoirs often contain high levels of asphaltenes, which can lead to deposition and blockages in production wells and reduce the flow of hydrocarbons during gas enhanced oil recovery (GEOR) techniques. This study aims to experimentally evaluate the impact of miscible and immiscible carbon dioxide (CO₂) and nitrogen (N₂) on asphaltene deposition and its impact on oil recovery performance in unconventional shale reservoirs.
This research began with a comprehensive literature review and data analysis of GEOR methods in unconventional …
Design And Development Of Biocompatible Mofs And Silica-Based Nanocarriers With Controlled Pharmacokinetics For Drug Delivery Applications,
2024
Missouri University of Science and Technology
Design And Development Of Biocompatible Mofs And Silica-Based Nanocarriers With Controlled Pharmacokinetics For Drug Delivery Applications, Neila Pederneira
Doctoral Dissertations
"In the past decade, a big interest has drawn into nanoporous metal-organic frameworks (MOFs) and silica-based materials as nanocarriers for drug delivery applications, owing to their exceptionally high surface area and highly structured porous network. The overall goal of this research was to optimize the pharmacokinetic behavior of several highly porous biocompatible drug carriers that have the potential to carry Ibuprofen, 5-Fluorouracil, and Curcumin to the desired tissue without creating a burst effect and minimizing the amount of dosage and size that conventional capsules require. The specific objectives of this study are to (i) assess the effect of drug solubility …
Lithospheric Drip And Mantle Thermal Upwelling Beneath Central Asia And The Southern Great Plains Of North America: Evidence From Receiver Function Imaging,
2024
Missouri University of Science and Technology
Lithospheric Drip And Mantle Thermal Upwelling Beneath Central Asia And The Southern Great Plains Of North America: Evidence From Receiver Function Imaging, Yangyang Liao
Doctoral Dissertations
"Investigating the depth of mantle transition zone (MTZ) discontinuities provides insights into mantle dynamics, including regional-scale downwelling of mantle lithosphere (i.e., lithospheric drip) and upwelling of thermal materials (i.e., mantle plume). In our study, we employ receiver functions to image the 410 km (d410) and 660 km (d660) mantle discontinuities and to ascertain thickness of the MTZ beneath Central Asia and the Great Plains in United States. The findings unveil a significantly thickened transition zone, exhibiting an average thickness of 284 km beneath East Sayan. When considered alongside geochemical observations, our results indicate that the descent of the lithosphere is …
Exploring Seismic Anisotropy In The Crust And Mantle Of The Tibetan Plateau And Analyzing Seismic Velocity Variations In Yellowstone,
2024
Missouri University of Science and Technology
Exploring Seismic Anisotropy In The Crust And Mantle Of The Tibetan Plateau And Analyzing Seismic Velocity Variations In Yellowstone, Cong Shen
Doctoral Dissertations
"Seismology is a scientific discipline that utilizes seismic waves to investigate the deep structures within the Earth's interior, which are otherwise inaccessible to direct observation by humans. These seismic waves can be categorized into two types: body waves and surface waves, each with distinct propagation modes and behaviors, carrying valuable information about their travel paths. The first paper concentrates on the analysis and inversion of body waves produced by large seismic events. It employs shear wave splitting and receiver function methods to explore the geodynamic structure of the south-central Tibetan Plateau, near the plate boundary. The investigation covers the depth …
Improving Syngas Quality In A Downdraft Biomass Gasifier With Blended Feedstocks,
2024
Missouri University of Science and Technology
Improving Syngas Quality In A Downdraft Biomass Gasifier With Blended Feedstocks, Rania Almusafir
Doctoral Dissertations
"Biomass gasification is the greatest potential renewable energy source and will play an important role in the energy mix of the future. To achieve a high quality of produced synthesis gas (syngas) in the gasification system, the syngas cleaning and cooling processes pose challenges. The main objectives of the present work are advancing the knowledge of the gasification process and producing syngas in the studied pilot-scale downdraft biomass gasifier.
A Thermogravimetric analysis (TGA) has been developed and utilized to experimentally investigate the impact of biomass feedstock diversity on the performance of the gasification process of hardwood (HW), softwood (SW) pellets, …
High Viscosity Friction Reducer Evaluation At High Temperature And High Tds Environments,
2024
Missouri University of Science and Technology
High Viscosity Friction Reducer Evaluation At High Temperature And High Tds Environments, Ghith Ali Ahmed Biheri
Doctoral Dissertations
"In unconventional reservoirs, proppant transport during hydraulic fracturing treatments could be successful when the proppant is placed further within the reservoir's fracture networks. This could increase the reservoir formation conductivities and improve the productivity of the wells. This job of improving the reservoir conductivity by distributing and transporting proppant can be conducted by reliable fracture fluids with excellent fluid rheology (e.g., viscosity and elasticity). However, several challenges, including the high temperatures and the presence of high TDS in produced water, may limit the capability of fracture fluids to transport proppant. Additionally, the use of fracture fluid has raised fears regarding …
A Critical Review Of Capillary Pressure Behavior And Characterization In Fractional-Wet Reservoirs,
2024
Edith Cowan University
A Critical Review Of Capillary Pressure Behavior And Characterization In Fractional-Wet Reservoirs, Yihang Xiao, Zhenjiang You, Lei Wang, Zhengtong Du
Research outputs 2022 to 2026
Fractional wettability is common in oil and gas reservoirs, resulting in complex fluid distribution and transport phenomena. A precise understanding of capillary pressure behavior and characterization in fractional-wet reservoirs, including the two-phase flow mechanisms within pores and relationship between capillary pressure and saturation in porous media, is significant to enhanced oil recovery strategies. In this paper, an in-depth review of the two-phase flow mechanisms in fractional-wet pores and capillary entry pressures in various displacement processes was conducted. Furthermore, the effects of oil-wet proportion and contact angle on capillary pressure characterization were summarized, highlighting the emergence of similar capillary pressure curves …
Regeneration By Electrodialysis Of Secondary Spent Monoethanolamine Solution Obtained After Mineralisation Of Captured Carbon Dioxide With Calcium Sulfate,
2024
Faculty of Engineering
Regeneration By Electrodialysis Of Secondary Spent Monoethanolamine Solution Obtained After Mineralisation Of Captured Carbon Dioxide With Calcium Sulfate, Ketwarang Nimnualrat
Chulalongkorn University Theses and Dissertations (Chula ETD)
The greenhouse effect has been impacting our planet further than we even realized. In recent years, the earth’s atmosphere has rapidly changed at a faster pace than ever. The main villain, mostly released from industry, is carbon dioxide (CO2), which contributes about 79.7 percent of total greenhouse gases. Consequently, Carbon Capture, Utilization and Storage (CCUS) has now become an important role to mitigate this problem. A widely used industrial medium for capturing CO2 is aqueous solution of monoethanolamine (MEA), which is capable of capturing CO2 from fossil fuel-fired processes. However, current MEA regeneration by stripping has high energy requirements for …
Polylactic Acid-Carbon Quantum Dots Composite (Pla/Cqds) For 3d-Printing Filament: Thermal, Mechanical, Morphological, And Electrical Properties,
2024
Faculty of Engineering
Polylactic Acid-Carbon Quantum Dots Composite (Pla/Cqds) For 3d-Printing Filament: Thermal, Mechanical, Morphological, And Electrical Properties, Saran Inthirach
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates polylactic acid carbon quantum dots composite (PLA/CQDs) for 3D-printing filament. composites were prepared by extrusion technique to ensure homogeneous dispersion of CQDs within the PLA matrix with various CQDs loadings (0.25 to 5 wt.%), Thermal analysis showed that 3 wt.% CQDs increased decomposition temperature from 369 °C to 382 °C and raised residual mass, indicating better heat resistance. Mechanical analysis revealed that 1 wt.% CQDs significantly improved tensile strength and 3 wt.% CQDs increased Young’s modulus, though elongation at break fell at 5 wt.% due to CQD aggregation. SEM-EDX confirmed smooth, well dispersed CQDs at low loadings, …
Enhance Effectiveness Of Monitoring Scheme Using Insar On Tailings Storage Facility No. 2, Chatree Gold Mine, Thailand,
2024
Faculty of Engineering
Enhance Effectiveness Of Monitoring Scheme Using Insar On Tailings Storage Facility No. 2, Chatree Gold Mine, Thailand, Shanghai Chea
Chulalongkorn University Theses and Dissertations (Chula ETD)
Tailings storage facility (TSF) is a critical component of the mining industry, serving to safely contain waste generated during mineral extraction. At Chatree Gold Mine, the largest and only active gold mine in Thailand, TSF No.2 handles approximately 5 million tons of tailings annually. Effective monitoring of the facility is crucial for hazard prevention and regulatory compliance. This study aims to enhance the monitoring scheme of TSF No.2 by employing Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique, processed via MintPy software, to analyze ground deformation. Despite traditional monitoring methods, such as in-situ geodetic surveying, offering valuable insights, they …
Recovery Of Tin From Kaolin Mine Tailing, Rangoon, Thailand,
2024
Faculty of Engineering
Recovery Of Tin From Kaolin Mine Tailing, Rangoon, Thailand, Archana Pandit
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates the recovery of tin from kaolin waste using gravity, electrostatic, and magnetic separation techniques. A total of 123.500 kg of sand and 103.200 kg of silt were processed using a shaking table, spiral concentrator, high-tension separator, induced roll magnetic separator, and Frantz magnetic separator. Mineralogical and chemical characterization was conducted using X-ray diffractometer (XRD), X-ray fluorescence (XRF), and microscopic analysis to determine tin distribution and occurrence. Experimental results showed that the silt fractions generally exhibited higher tin content than the sand fractions. In this study, Case A refers to the samples (Sand A and Silt A) processed …
Ethanol-Assisted Co2 Hydrogenation To Methanol In A Trickle-Bed Reactor,
2024
Faculty of Engineering
Ethanol-Assisted Co2 Hydrogenation To Methanol In A Trickle-Bed Reactor, Pattarapol Akeakkharanusorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
The hydrogenation of carbon dioxide (CO2) to methanol is a promising approach for CO2 utilization. However, conventional methanol synthesis is thermodynamically limited at high temperatures. Alcohol-assisted methanol synthesis has emerged as a novel low-temperature method, using alcohol as a catalytic solvent to alter reaction pathways. Equilibrium analysis using Gibbs free energy minimization in Aspen Plus showed that increasing ethanol enhanced CO2 conversion and methanol yield. At high ethanol concentrations, ethanol remained in the liquid phase. This study investigated ethanol-assisted CO2 hydrogenation in a trickle-bed reactor using a commercial Cu/ZnO/Al2O3 catalyst. CO2 and H2 were introduced in gaseous form, while ethanol …
Simulation Study For Enhancing Thermal Performance Of Cotton Facemasks Through Integration Of Organic Phase Change Materials,
2024
Faculty of Engineering
Simulation Study For Enhancing Thermal Performance Of Cotton Facemasks Through Integration Of Organic Phase Change Materials, Poptham Chaviengpop
Chulalongkorn University Theses and Dissertations (Chula ETD)
Climate change has caused temperature extremities around the world. Maintaining body temperature against cold temperatures is important for preventing long term health risks. PCM incorporated facemasks offers the solution to this problem. In this study, computational fluid dynamics utilizing laminar flow of air in a simulated wind chamber is used to model the human breathing cycle in cold environments (0-10°C) through four different types of PCM incorporation facemasks (random, coating, hollow fiber, and lamination) used in the industry and three separate PCM candidates (n-octadecane, capric acid, and PEG-600). The findings indicates that the facemask utilizing the coating PCM incorporation method …
Mg And Ce Doping On Cu/Zno/Al2o3 Catalysts For Methanol Synthesis From Ethanol-Assisted Carbon Dioxide Hydrogenation In Fixed-Bed Reactor,
2024
Faculty of Engineering
Mg And Ce Doping On Cu/Zno/Al2o3 Catalysts For Methanol Synthesis From Ethanol-Assisted Carbon Dioxide Hydrogenation In Fixed-Bed Reactor, Panisara Kampaeng
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, the world is facing the problem of global warming causing by excessive carbon dioxide (CO2). According to the WMO report, the global surface temperature is expected to increase if no serious mitigation strategies are implemented. Carbon capture utilization (CCU) of a low value greenhouse gas into high-value chemicals is an approach to reduce emissions and valuable chemical production. Among the various CO2 conversion technologies, thermo-catalytic reaction using hydrogen is the most suitable for industrial applications. Methanol is used as a fuel, solvent, and raw material for high value chemicals. Conventional methanol synthesis has thermodynamic limitations, as the reaction is …
