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Controlling The Emission Of Volatile Platinum Oxides To The Vapor Phase In Diesel Oxidation Catalysts, Arnab Ghosh 2022 University of New Mexico - Main Campus

Controlling The Emission Of Volatile Platinum Oxides To The Vapor Phase In Diesel Oxidation Catalysts, Arnab Ghosh

Nanoscience and Microsystems ETDs

Pt-based catalysts are used for the treatment of emissions from vehicles, particularly in Diesel oxidation catalysts (DOCs). Three-way catalysts are treated at temperatures ranging from 950℃-1050℃ while DOCs are aged at 800℃ for 50 hrs. At 800°C, Pt reacts with O2 to form PtO2 which has a high vapor pressure and can be transported through the vapor phase. These accelerated aging conditions lead to the formation of large Pt particles causing a loss of catalytic activity. In this thesis, we used model thin-film catalysts that made it possible to quantify the emission of Pt to the vapor phase …


Particle Formation And Thermal Radiation In Laminar Diffusion Flames With Applications To Energy And Materials, Phillip Irace 2022 Washington University in St. Louis

Particle Formation And Thermal Radiation In Laminar Diffusion Flames With Applications To Energy And Materials, Phillip Irace

McKelvey School of Engineering Graduate Student Theses & Dissertations

Fossil fuels supply over 80% of the world’s primary energy, and if current policy and technology trends continue, global energy and energy-related carbon dioxide (CO2) emissions are predicted to increase for at least several decades owing to population and economic growth, leading to serious concerns regarding global warming. Natural gas releases less CO2 than other fossil fuels (e.g., coal and oil) and can help meet future CO2 emission targets. Natural gas combustion, however, has poor radiation heat transfer when compared to other fossil fuels owing to its low propensity for soot formation, making it difficult to use as a drop-in …


A Drift-Flux Model For Upward Two-Phase In Pipes With High Velocity Flows, Woochan Lee 2022 Louisiana State University and Agricultural and Mechanical College

A Drift-Flux Model For Upward Two-Phase In Pipes With High Velocity Flows, Woochan Lee

LSU Doctoral Dissertations

This study proposes the evaluation and development of a drift-flux model for upward two-phase high-velocity flow in large diameter pipes. A case where the proposed model is applicable is WCD (Worst-Case-Discharge) calculations for offshore wells. WCD assumes relatively larger pipe diameters and higher flow rates than the flow experiments at laboratory conditions utilized to validate and develop most of the flow models available in the literature.

Most of the two-phase flow models describe flow regime transitions as discrete processes by assigning the required void fraction or velocity for each flow regime transition. Therefore, for each flow regime, flow-regime-dependent correlations or …


Photocatalytic Degradation Of Organic Contaminants By Titania Particles Produced By Flame Spray Pyrolysis, Noah Babik 2022 Mississippi State University

Photocatalytic Degradation Of Organic Contaminants By Titania Particles Produced By Flame Spray Pyrolysis, Noah Babik

Theses and Dissertations

Advanced oxidation of organic pollutants with TiO2 photocatalysts is limited due to the wide bandgap of TiO2, 3.2 eV, which requires ultraviolet (UV) radiation. When nanosized TiO2 is modified by carbon doping, charge recombination is inhibited and the bandgap is narrowed, allowing for efficient photodegradation under visible light. Here, we propose a flame spray pyrolysis (FSP) technique to create TiO2. The facile process of FSP has been successful in preparing highly crystalline TiO2 nanoparticles. Using the same procedure to deposit TiO2 onto biochar, the photocatalyst was doped by the carbonaceous material. The morphology, crystalline and electronic structure of the FSP …


Receptor-Doped Organic Transistors: Transducing Anion Binding From Mixed Ionic-Electronic Transport, Anthony Benasco 2022 University of Southern Mississippi

Receptor-Doped Organic Transistors: Transducing Anion Binding From Mixed Ionic-Electronic Transport, Anthony Benasco

Dissertations

Organic semiconductors based on π-conjugated polymers show remarkable properties such as high tolerance to structural defects, low processing temperature requirements, biocompatibility, ease of fabrication, and tunable properties. Conjugated polymers integrated into device arrays can exhibit collective properties sensitive to minor perturbations in the surrounding media. However, these devices rely on serendipitous sensitivity to the analyte of interest, and strategies for specific detection remain a considerable change. There remains a compelling, global need for technologies to monitor phosphate due to its prevalence in agricultural runoff, leading to fish kills and economic decline for commercial and recreational fisheries. The strong hydration energies …


Molecular-Level Control Over Ionic Conduction And Ionic Current Direction By Designing Macrocycle-Based Ionomers, Shyambo Chatterjee, Ehsan Zamani, Seefat Farzin, Iman Evazzade, Oghenetega Allen Obewhere, Tyler James Johnson, Vitaly Alexandrov, Shudipto Konika Dishari 2022 University of Nebraska-Lincoln

Molecular-Level Control Over Ionic Conduction And Ionic Current Direction By Designing Macrocycle-Based Ionomers, Shyambo Chatterjee, Ehsan Zamani, Seefat Farzin, Iman Evazzade, Oghenetega Allen Obewhere, Tyler James Johnson, Vitaly Alexandrov, Shudipto Konika Dishari

Department of Chemical and Biomolecular Engineering: Faculty Publications

Poor ionic conductivity of the catalyst-binding, submicrometer- thick ionomer layers in energy conversion and storage devices is a huge challenge. However, ionomers are rarely designed keeping in mind the specific issues associated with nanoconfinement. Here, we designed nature-inspired ionomers (calix-2) having hollow, macrocyclic, calix[4]arene-based repeat units with precise, sub-nanometer diameter. In ≤100 nm-thick films, the in-plane proton conductivity of calix-2 was up to 8 times higher than the current benchmark ionomer Nafion at 85% relative humidity (RH), while it was 1−2 orders of magnitude higher than Nafion at 20−25% RH. Confocal laser scanning microscopy and other synthetic techniques allowed us …


Chiral Liquid Crystal Microdroplets For Sensing Phospholipid Amphiphiles, Sepideh Norouzi, Jose A. Martinez Gonzalez, Monirosadat (Sanaz) Sadati 2022 University of South Carolina

Chiral Liquid Crystal Microdroplets For Sensing Phospholipid Amphiphiles, Sepideh Norouzi, Jose A. Martinez Gonzalez, Monirosadat (Sanaz) Sadati

Faculty Publications

Designing simple, sensitive, fast, and inexpensive readout devices to detect biological molecules and biomarkers is crucial for early diagnosis and treatments. Here, we have studied the interaction of the chiral liquid crystal (CLC) and biomolecules at the liquid crystal (LC)-droplet interface. CLC droplets with high and low chirality were prepared using a microfluidic device. We explored the reconfiguration of the CLC molecules confined in droplets in the presence of 1,2-diauroyl-sn-glycero3-phosphatidylcholine (DLPC) phospholipid. Cross-polarized optical microscopy and spectrometry techniques were employed to monitor the effect of droplet size and DLPC concentration on the structural reorganization of the CLC molecules. Our results …


Nuclear Energy As A Reliable And Safe Source Of Power Generation, Sarup Dhungana 2022 University of Mississippi

Nuclear Energy As A Reliable And Safe Source Of Power Generation, Sarup Dhungana

Honors Theses

There is a high demand of energy for generating civil applicable power in the world and in the USA, correspondingly. The world has been consuming various sources to extract the power to meet its demands. Most of the power sources include renewable and non-renewable sources like fossil fuels, natural gas, coal, water, solar, wind, and nuclear power. Although most of these sources have many advantages in terms of their capacity and cost of production, nuclear power can be categorized as the emerging driving force in the United States and in the world for power generation, because of its reliability and …


Optimization Of An Ethylbenzene To Styrene Production Facility, John Michels 2022 University of Mississippi

Optimization Of An Ethylbenzene To Styrene Production Facility, John Michels

Honors Theses

The purpose of this case study is to optimize the design and production of an ethylbenzene-to-styrene manufacturing facility, Unit 500. Compared to the original base-case design, the optimizations presented in this document will save approximately $337 million dollars without compromising the production requirements or quality. Optimization of this process used net present value as an objective function, with changes centered around the reactors, but also the separation equipment and exchangers prior to separation, as those devices most directly controlled process stream contents and conditions. The second set of reactors was removed in favor of using one optimized set of reactors, …


Optimization And Analysis Of A Styrene Production Process, Alexis Kimpel 2022 University of Mississippi

Optimization And Analysis Of A Styrene Production Process, Alexis Kimpel

Honors Theses

The production of styrene from ethylbenzene in Unit 500 is designed to start up in 2024 and operate for 12 years after startup. The engineering team was tasked with designing the process, creating an economic model, and optimizing the net present value (NPV). The process was simulated in AVEVA PRO/II Simulation for the design process and to estimate the size of equipment. Parametric and topological optimization was performed subsequently on the unit operations in the process. The NPV was improved by $423M from a base case of -$919M to an optimized case of -$496M. The project is recommended to continue …


The Design And Economic Optimization Of A Warehouse Refrigeration System, Hannah Talbot 2022 University of Mississippi

The Design And Economic Optimization Of A Warehouse Refrigeration System, Hannah Talbot

Honors Theses

The purpose of this project was to design a cool warehouse refrigeration system for Acme Frozen Foods, Inc located in Newark, New Jersey. The refrigeration system was used to cool eighteen 300,000 ft3 refrigerated units (200 ft x 100 ft x 15 ft), each requiring 200 cooling tons of refrigeration at a level of 0 F. The scope of this project included determining the appropriate refrigeration cycle, selecting the most desirable refrigerant, and temperature ranges to optimize the performance of the system. This project also considered the economic cost of the power needed to run the refrigerated units and …


Optimization Of Styrene From Ethylbenzene Case Study, Jabria Daria Thompson 2022 University of Mississippi

Optimization Of Styrene From Ethylbenzene Case Study, Jabria Daria Thompson

Honors Theses

The following pages detail the optimization process of styrene from ethylbenzene in the Styrene Production Plant, Unit 500. There were two parts of the assignment, each with slightly different end goals. The goal of the first part of the assignment, was to create a process that would effectively and efficiently increase the negative Net Present Value (NPV) of the production plant. Procedures taken in this process included developing a working kinetic process simulation model and optimizing this model through unit operations and heat integration, as well as developing an accurate economic model that will be used to evaluate the proposed …


Energy And Resource-Saving Method For Enriching The Waste Water Purified Without Sufficient Purification With Oxygen, Dilobar KHURRAMOVA, Mukhtor KHURRAMOV, Sharifa GANIEVA, Zulqaynar NAZIROV 2022 Karshi State University, Karshi, Uzbekistan

Energy And Resource-Saving Method For Enriching The Waste Water Purified Without Sufficient Purification With Oxygen, Dilobar Khurramova, Mukhtor Khurramov, Sharifa Ganieva, Zulqaynar Nazirov

CHEMISTRY AND CHEMICAL ENGINEERING

In order to implement a reliable and environmentally safe, economically viable method of wastewater enrichment, the goal is to develop an energy- and resource-saving method of oxygen enrichment of wastewater that has not undergone sufficient treatment. Cleaning is carried out in a tank, which is built using rock, which is an algal limestone. Limestone contributes to the improvement of the oxygen regime due to the “conservation” of organic matter in anoxic bottom layers and the acceleration of the process of photosynthesis of unicellular algae. Calcium carbonate is a reagent that provides not only automatic stabilization of water pH at 2/dm …


Kinetics Of Carboxymethylation Reaction Of Cellulose Samples With Different Degree Of Crystallinity, Ilkhom GOYIBNAZAROV, Sherzod YULDOSHOV, Abdushukhur SARIMSOKOV 2022 Institute of Polymer Chemistry and Physics, Tashkent, Uzbekistan

Kinetics Of Carboxymethylation Reaction Of Cellulose Samples With Different Degree Of Crystallinity, Ilkhom Goyibnazarov, Sherzod Yuldoshov, Abdushukhur Sarimsokov

CHEMISTRY AND CHEMICAL ENGINEERING

No abstract provided.


Mathematical Modeling Of Synthesis 4´,4´´-Di-(1-Methyl-1-Hydroxy-2-Phenylethynyl)-Dibenzo-18-Crown-6, Lyubov KOZINSKAYA, Dilorom MIRKHAMITOVA 2022 National University of Uzbekistan, Tashkent, Uzbekistan

Mathematical Modeling Of Synthesis 4´,4´´-Di-(1-Methyl-1-Hydroxy-2-Phenylethynyl)-Dibenzo-18-Crown-6, Lyubov Kozinskaya, Dilorom Mirkhamitova

CHEMISTRY AND CHEMICAL ENGINEERING

The main goal of this study is the mathematical modeling of the optimal conditions for the synthesis of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 by the least squares method. In the STAT program, iconograms of mathematical modeling of the synthesis and the dependence of the rate of formation of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 on temperature and reaction time were obtained, the corresponding analytical dependencies are determined. Mathematical processing of the results of the synthesis of 4´,4´´-di-(1-methyl-1-hydroxy-2-phenylethynyl)-dibenzo-18-crown-6 was carried out, a system of linear equations was compiled using the matrix method. The average reaction rate and the optimum of the mathematical model were determined, and the experimental and calculated …


Optimization Of A Styrene Prodcution And Separation Process, Bryce Little 2022 University of Mississippi

Optimization Of A Styrene Prodcution And Separation Process, Bryce Little

Honors Theses

A step wise optimization of Unit 500 was completed. Unit 500 is a planned ethylbenzene to styrene production plant that has a annual production goal of 100,000 metric tons of styrene. The cost of styrene on the market is $1,598. The base case of Unit 500 produced styrene at a cost of $2,650. Optimization was completed with an emphasis on parametric changes though material of construction and heat integration were also considered. The optimized Unit 500 design reduced the cost of styrene production to $2,035 per metric ton. While this represents a significant improvement on the base case cost, it …


Probing Myosin Ensemble Mechanics In Actin Filament Bundles Using Optical Tweezers, Omayma Al Azzam, Janie C. Watts, Justin E. Reynolds, Juliana E. Davis, Dana N. Reinemann 2022 University of Mississippi

Probing Myosin Ensemble Mechanics In Actin Filament Bundles Using Optical Tweezers, Omayma Al Azzam, Janie C. Watts, Justin E. Reynolds, Juliana E. Davis, Dana N. Reinemann

Faculty and Student Publications

Myosins are motor proteins that hydrolyze ATP to step along actin filament (AF) tracks and are essential in cellular processes such as motility and muscle contraction. To understand their force-generating mechanisms, myosin II has been investigated both at the single-molecule (SM) level and as teams of motors in vitro using biophysical methods such as optical trapping. These studies showed that myosin force-generating behavior can differ greatly when moving from the single-molecule level in a three-bead arrangement to groups of motors working together on a rigid bead or coverslip surface in a gliding arrangement. However, these assay constructions do not permit …


Optimization Of A Fluidized Bed Reactor For The Production Of Styrene From Ethylbenzene, Gregory Espenan 2022 University of Mississippi

Optimization Of A Fluidized Bed Reactor For The Production Of Styrene From Ethylbenzene, Gregory Espenan

Honors Theses

In order to optimize Unit 500, a styrene production plant, the Net Present Value (NPV) was used as the objective function to ensure every optimization strategy had a positive economic effect. To optimize a chemical plant, it is important to note efficiency, economics, product specifications, and production requirements. The goal of this project was to make changes to the base case of Unit 500 to minimize the cost to produce styrene for an upstream unit. PRO/II was used to simulate various points in different unit operations throughout the process. The NPV was measured after each unit operation was simulated to …


A Data-Based Framework For Monitoring And Controlling Particulate Systems, Vidhyadhar Manee 2022 Louisiana State University and Agricultural and Mechanical College

A Data-Based Framework For Monitoring And Controlling Particulate Systems, Vidhyadhar Manee

LSU Doctoral Dissertations

One of the limitations of conventional monitoring tools in crystallization is the inability to deal with high solids concentration. Image-based monitoring, in which RGB images of the solution are captured and analyzed by an object detection software, has been a promising alternative. The software used in these tools primarily depends on hand-coded heuristics to distinguish between the signal and the noise. With the recent success of supervised deep learning, a newer paradigm has emerged in which the heuristics can be learnt from labeled images. This approach is founded on the idea that it is easier to develop labels for data …


A New Look At Landslides Of The Vermilion And Echo Cliffs, Northern Arizona, Conor M. Watkins, J. David Rogers 2022 Missouri University of Science and Technology

A New Look At Landslides Of The Vermilion And Echo Cliffs, Northern Arizona, Conor M. Watkins, J. David Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Vermilion and Echo Cliffs form a nearly continuous escarpment more than 160 km long within the Colorado Plateau physiographic province of North America. The cliffs overlie the Marble Platform in northern Arizona and are located along the Colorado River, just upstream of the Grand Canyon. Large rotational block landslides mantle the erosional escarpment along most of its extent. Although these landslides have been noted for over 100 years, their likely origin has never been explained. Landslide failure surfaces appear to be influenced by the Petrified Forest Member of the Triassic Chinle Formation, a shale layer containing smectite clay weathered …


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