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Full-Text Articles in Engineering

Evaluation Of Capacitive Deionization Desalination Technology For Irrigation, Ziad Khalifa, Moustafa Elshafei Prof, Abdalrahman Amer, Eng, Ashraf Seleym Dr, Tamer Samir Eng Feb 2020

Evaluation Of Capacitive Deionization Desalination Technology For Irrigation, Ziad Khalifa, Moustafa Elshafei Prof, Abdalrahman Amer, Eng, Ashraf Seleym Dr, Tamer Samir Eng

Chemical Engineering

Desalination of brackish groundwater has great potential to alleviate the problem of the limited water resources in Egypt. In this paper, we studied the desalination of brackish water for irrigation purposes using capacitive deionization (CDI) technology. We investigated a modular unit for use in greenhouses (GH). A GH for the production of tomato requires about 3.2 m3/d of water. The target CDI unit has a production capacity of 32 m3/d for irrigation of 10 greenhouses from brackish water. The paper provides an extensive simulation study to illustrate the influence of various design parameters and to unveil the CDI technology pros …


Preparation, Characterization And Biological Activity Of Novel Schiff Base Complexes Based On La, Er And Yb Metal Ions, Hoda Ahmed, Walaa H. Mahmoud, Islam M. Al-Akraa Dr, Gehad G. Mohamed Feb 2020

Preparation, Characterization And Biological Activity Of Novel Schiff Base Complexes Based On La, Er And Yb Metal Ions, Hoda Ahmed, Walaa H. Mahmoud, Islam M. Al-Akraa Dr, Gehad G. Mohamed

Chemical Engineering

The tridentate [HL, (4-[(2-(2-quinolinoimino)-3, 5-dibromobenzyl) amino] cyclohexanol)]Schiff base ligand was prepared from the condensation reaction of 2-quinoline carbaldehyde with the drug ambroxol. The prepared HL ligand was further used in the preparation of some new complexes via the reaction with La(III), Er(III) and Yb(III) metal ions. The geometry of the prepared complexes was proposed from elemental analysis, FT-IR, 1H NMR, thermal and magnetic susceptibility. 1H NMR showed that the three nitrogen atoms of the ligand were responsible for the complex formation. The thermal analysis technique provided a clear prospect about the decomposition steps of the Schiff base ligand and its …


Experimental Investigation Of Bio-Enhancer Drilling Fluid Additive: Can Palm Tree Leaves Be Utilized As A Supportive Eco-Friendly Additive In Water-Based Drilling Fluid System?, Abo Taleb T. Al-Hameedi, Husam H. Alkinani, Shari Dunn-Norman, Mustafa A. Al-Alwani, Waleed H. Al-Bazzaz, Abdullah F. Alshammari, Hussien W. Albazzaz, Rusul A. Mutar Feb 2020

Experimental Investigation Of Bio-Enhancer Drilling Fluid Additive: Can Palm Tree Leaves Be Utilized As A Supportive Eco-Friendly Additive In Water-Based Drilling Fluid System?, Abo Taleb T. Al-Hameedi, Husam H. Alkinani, Shari Dunn-Norman, Mustafa A. Al-Alwani, Waleed H. Al-Bazzaz, Abdullah F. Alshammari, Hussien W. Albazzaz, Rusul A. Mutar

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Serious problems will be presented due to using conventional chemical additives to regulate the drilling mud properties, as they have health, safety, and environmental side effects. Thus, there is a considerable necessity for alternative multifunctional bio-enhancer drilling mud additives, which can assist in optimizing the drilling fluid specifications and enhance its effectiveness with the least effects on the environment and the drilling personnel safety. The effects of adding two concentrations of palm tree leaves powder (PTLP) to water-based mud were conducted under fresh and aged conditions using standard API drilling fluids testing methods such as rheometer/viscometer, pH meter and temperature, …


Efficient Catalytic Production Of Biodiesel Using Nano-Sized Sugar Beet Agro-Industrial Waste, Hosam H. Abdelhady, Hany A. Elazab, Emad M. Ewais, Mohamed Saber, Mohamed S. El-Deab Feb 2020

Efficient Catalytic Production Of Biodiesel Using Nano-Sized Sugar Beet Agro-Industrial Waste, Hosam H. Abdelhady, Hany A. Elazab, Emad M. Ewais, Mohamed Saber, Mohamed S. El-Deab

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper addresses the use of agro-industrial residue as a promising heterogeneous catalyst for the efficient production of biodiesel. That is, CaO-rich Sugarbeet agro-industrial waste (smashed down to nano-size) shows superb catalytic activity for biodiesel production via transesterification process employing sunflower oil and methanol. Physicochemical properties of the proposed catalyst are probed by TGA–DTG, XRF, XRD, FT-IR, SEM, BET, and CO2-TPD techniques. Biodiesel conversion (%) of Ca. 93% is achieved under the optimal conditions (catalyst loading of 1 wt%, methanol/oil molar ratio of 4.5:1, refluxed at 75 °C for 60 min). The relatively short reaction time indicates the enhanced kinetics …


Mathematica As An Efficient Tool To Optimize The Kinetic Study Of Ethyl Acetate Hydrolysis, M. H. El Dewaik, Mamdouh Gadalla, M. A. Sadek, Hany A. Elazab Feb 2020

Mathematica As An Efficient Tool To Optimize The Kinetic Study Of Ethyl Acetate Hydrolysis, M. H. El Dewaik, Mamdouh Gadalla, M. A. Sadek, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

Mathematica is a powerful program for computing both numeric and algebraic calculations as well as graphing two- and three-dimensional curves and surfaces. It is used increasingly in many fields of science now such as physics, engineering, chemistry and even biology because of the fast interaction of mathematics with almost the fields of science nowadays. We report here, optimizing the kinetic data for the hydrolysis of ethyl acetate through caustic soda via using Mathematica.


Development Of Novel Adsorbent For Industrial Wastewater Treatment, Hassaan M. Shehata, Dalia A. Ali, Islam M. Al-Akraa, Hoda A. Elsawy, Hany A. Elazab Feb 2020

Development Of Novel Adsorbent For Industrial Wastewater Treatment, Hassaan M. Shehata, Dalia A. Ali, Islam M. Al-Akraa, Hoda A. Elsawy, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

The main objective of this research project is to perform some experimental procedures to inform the ability of the novel adsorbent used in this project. The chemical modification of the adsorbent is the chemical oxidation of pure powder chitosan using some specific redox pairs which are potassium dichromate and sodium bisulphite. After preparing the modified chitosan, there are some parameters that must be discussed during the adsorption process. The first parameter is the time parameter, showing experimentally the optimum time for adsorption under certain conditions by collecting values of absorbance and concentration of thymol blue adsorbed after the process from …


Synthesis And Characterization Of Chitosan Based Catalyst For Catalysis Applications, Hany A. Elazab, Yousab G. Remiz, Mostafa A. Radwan, M. A. Sadek Feb 2020

Synthesis And Characterization Of Chitosan Based Catalyst For Catalysis Applications, Hany A. Elazab, Yousab G. Remiz, Mostafa A. Radwan, M. A. Sadek

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this research, chitosan-based catalyst synthesis and characterization was investigated for different application in catalysis as chitosan-based catalyst was combined with metal oxides in order to be used in dye removal of methyl orange (MO). Diluted acetic acid was used to dissolve chitosan then different percentages for metallic ions were mixed with diluted chitosan and then, 500 µL were added to the sample to reduce the metal salts then, microwave was used to heat the mixture for 5 minutes and then dried at 80-100 °C. Finally, X- ray diffraction was used to confirm the catalyst prepared. The aim of this …


Full-Set Measurements Dataset For A Water-Based Drilling Fluid Utilizing Biodegradable Environmentally Friendly Drilling Fluid Additives Generated From Waste, Abo Taleb Al-Hameedi, Husam Hasan Alkinani, Shari Dunn-Norman, Mohammed M. Alkhamis, Justin D. Feliz Feb 2020

Full-Set Measurements Dataset For A Water-Based Drilling Fluid Utilizing Biodegradable Environmentally Friendly Drilling Fluid Additives Generated From Waste, Abo Taleb Al-Hameedi, Husam Hasan Alkinani, Shari Dunn-Norman, Mohammed M. Alkhamis, Justin D. Feliz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The oil and gas industry is moving towards more environmentally friendly practices. The environmental regulations regarding drilling waste management and disposal are motivating the industry to be more efficient with drilling operations. Environmentally friendly drilling fluid additives used in drilling operations reduces not only the negative implications on the environment but also reduces costs. This paper provides an experimental dataset of utilizing biodegradable waste materials as environmentally friendly drilling fluid additives. The data were collected through experimental evaluations of several waste materials including Potato Peels Powder (PPP), Mandarin Peels Powder (MPP), Fibrous Food Waste Material (FFWM), Palm Tree Leaves Powder …


Impact Of Team Formation Approach On Teamwork Effectiveness And Performance In An Upper-Level Undergraduate Chemical Engineering Laboratory Course, Erick S. Vasquez, Matthew J. Dewitt, Zachary J. West, Michael J. Elsass Feb 2020

Impact Of Team Formation Approach On Teamwork Effectiveness And Performance In An Upper-Level Undergraduate Chemical Engineering Laboratory Course, Erick S. Vasquez, Matthew J. Dewitt, Zachary J. West, Michael J. Elsass

Chemical and Materials Engineering Faculty Publications

This study focuses on the impact of team formation approach on teamwork effectiveness and performance spanning three years of instruction of the chemical engineering unit operations laboratory, which is an upper-level undergraduate laboratory course. Team formation approaches changed each year, and assessment tools, including peer-assessment, academic performance, and course evaluations, were employed to evaluate team performance. Approaches included three cases: instructor-selected teams based on GPA with the objective of a similar cumulative average GPA for each team, student self-selected teams, and a combination of self-selected teams with instructor-selected teams for a final experiment. For the third case, new teams were …


Experimental Investigation Of Environmentally Friendly Drilling Fluid Additives (Mandarin Peels Powder) To Substitute The Conventional Chemicals Used In Water-Based Drilling Fluid, Abo Taleb T. Al-Hameedi, Husam H. Alkinani, Shari Dunn-Norman, Mustafa A. Al-Alwani, Abdullah F. Alshammari, Mohammed M. Alkhamis, Rusul A. Mutar, Waleed H. Al-Bazzaz Feb 2020

Experimental Investigation Of Environmentally Friendly Drilling Fluid Additives (Mandarin Peels Powder) To Substitute The Conventional Chemicals Used In Water-Based Drilling Fluid, Abo Taleb T. Al-Hameedi, Husam H. Alkinani, Shari Dunn-Norman, Mustafa A. Al-Alwani, Abdullah F. Alshammari, Mohammed M. Alkhamis, Rusul A. Mutar, Waleed H. Al-Bazzaz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The non-biodegradable additives used in controlling drilling fluid properties cause harm to the environment and personal safety. Thus, there is a need for alternative drilling fluid additives to reduce the amount of non-biodegradable waste disposed to the environment. This work investigates the potential of using mandarin peels powder (MPP), a food waste product, as a new environmentally friendly drilling fluid additive. A complete set of tests were conducted to recognize the impact of MPP on the drilling fluid properties. The results of MPP were compared to low viscosity polyanionic cellulose (PAC-LV), commonly used chemical additive for the drilling fluid. The …


Effect Of Tio2 Doping On Degradation Rate, Microstructure And Strength Of Borate Bioactive Glass Scaffolds, Romina Shafaghi, Omar Rodriguez, Sunjeev Phull, Emil H. Schemitsch, Paul Zalzal, Stephen D. Waldman, Marcello Papini, Mark R. Towler Feb 2020

Effect Of Tio2 Doping On Degradation Rate, Microstructure And Strength Of Borate Bioactive Glass Scaffolds, Romina Shafaghi, Omar Rodriguez, Sunjeev Phull, Emil H. Schemitsch, Paul Zalzal, Stephen D. Waldman, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

A titanium-containing borate glass series based on the system (52-X) B2O3–12CaO–6P2O5–14Na2O–16ZnO-XTiO2 with X varying from 0, 5 and 15 mol% of TiO2 incorporated, identified as BRT0, BRT1 and BRT3, respectively, were used in this study. Scaffolds (pore sizes, 165–230 μm and porosity, 53.51–69.51%) were prepared using a polymer foam replication technique. BRT3 scaffolds exhibited higher compressive strength (7.16 ± 0.22 MPa) when compared to BRT0 (6.02 ± 0.47 MPa) and BRT1 (5.65 ± 0.28 MPa) scaffolds with lower, or no, TiO2 content. The solubility of the scaffolds decreased …


Dry And Wet Torrefaction Of Microalgal Biomass For Biochar Production As Bioenergy Sources, Yong Yang Gan Feb 2020

Dry And Wet Torrefaction Of Microalgal Biomass For Biochar Production As Bioenergy Sources, Yong Yang Gan

Student Works (2020-2029)

Increasing population in global and living standards have risen the consumption of global energy. Thermochemical conversion approaches hold great potential for the biomass conversion into energy applications. Among these approaches, torrefaction is a promising technique to enhance the biomass properties, making it more practical and suitable in biofuel applications. In this study, two different species of microalgae (third generation biofuel feedstock) including Chlorella vulgaris ESP-31 and FSP-E were used as feedstocks for dry and wet torrefaction. Dry torrefaction of microalgae was performed at temperatures of 200, 250 and 300 ºC, and holding times of 15, 30, 45 and 60 min, …


Noble-Transition Alloy Absorbers For Near-Infrared Hot-Carrier Optoelectronics, Sara Karoline Figueiredo Stofela Jan 2020

Noble-Transition Alloy Absorbers For Near-Infrared Hot-Carrier Optoelectronics, Sara Karoline Figueiredo Stofela

LSU Doctoral Dissertations

Optoelectronics is the field of technology concerned with the study and application of electronic devices that source, detect and control light. Here we focus on the optical communications field which relies on optical fiber systems to carry signals to their destinations operating in the near-infrared range. To improve the performance of current optical fiber systems, one of the paths is to develop better near-infrared photodetectors.

The current group of materials used for near-infrared photodetection relies in the III-V semiconductor family. Although their spectral photosensitivity correlates well with the near-infrared, response time performance and electronic circuit integration remain limited for this …


Experimental And Computational Tools For Single Cell Analysis In Cancer Diagnostics, Manibarathi Vaithiyanathan Jan 2020

Experimental And Computational Tools For Single Cell Analysis In Cancer Diagnostics, Manibarathi Vaithiyanathan

LSU Doctoral Dissertations

Substantial evidence shows that cellular heterogeneity commonly exists within an isogenic or clonal population. Whether in isolation or caused through a combination of the above events, cellular heterogeneity can dramatically influence cellular decision making and cell fate, however, this can be masked by the average response from a population. One approach to solve this issue is to analyze a population at the individual cell level. The goal of this work is to develop high-throughput experimental and computational platforms to screen and quantify single cancer cells for specific intracellular enzyme activities. An interdisciplinary approach was taken to 1) better understand the …


Experimental Evaluation Of How Mineralogy And Microstructure Impact Micro-Geomechanics Of Shale Rocks, Hui Du Jan 2020

Experimental Evaluation Of How Mineralogy And Microstructure Impact Micro-Geomechanics Of Shale Rocks, Hui Du

LSU Doctoral Dissertations

Shales play an essential role in petroleum exploration and production because they can occur either as unconventional reservoir rocks for hydrocarbon extraction via hydraulic fracturing or as caprocks for conventional reservoirs and subsurface gas/ waste storage. For both extraction and storage applications, the success rate is directly depending on the rigorous candidate selection. Conventional rock characterization techniques normally measure rock properties by seismic/logging at the reservoir scale, and on drilled/outcrop cores at the core scale. However, shales are highly heterogeneous in composition, containing a large number of reactive minerals in micro/nanoscale with significantly different properties. The structural features and properties …


The Desorption Kinetics Of Methane From Nonaqueous Fluids For Enhanced Well Control, James Lee Nielsen Jr. Jan 2020

The Desorption Kinetics Of Methane From Nonaqueous Fluids For Enhanced Well Control, James Lee Nielsen Jr.

LSU Master's Theses

The mass transfer of a dissolved gas evolving to return to the gaseous phase from a liquid is governed by many parameters. This process affects the development of an oil and gas well due to the possibility of gas contamination occurring from either an influx entering the wellbore, or drilling through gas-bearing formations. Once this dissolved hydrocarbon gas circulates up the wellbore, it will begin to evolve from solution and poses a potential risk to drilling equipment, the environment, and personnel at a drilling rig. Being able to predict the behavior of gas desorption based on a known set of …


First-Principle Study On The Interaction Of Ligands With Gold And Effects On Catalytic Activities, Xun Cheng Jan 2020

First-Principle Study On The Interaction Of Ligands With Gold And Effects On Catalytic Activities, Xun Cheng

LSU Doctoral Dissertations

The extensive use of fossil fuels has increased the atmospheric concentration of CO2, resulting in global climate change. One way to mitigate the CO2 challenge is to convert it into useful chemicals electrocatalytically using renewable energies. Recent studies suggest that ligand-modified gold electrodes can enhance the Faradaic efficiency (FE) and selectivity of the electrochemical CO2 reduction reaction (CO2RR). This theoretical research, primarily based on density functional theory (DFT), has been carried out to understand the interactions of ligands with Au and possible effects on electrocatalytic activities. We systematically modeled and studied the adsorption of …


A Study Of Particle-Laden Flows From Meso And Micro-Scale Perspectives, Daniel Guedes De Oliveira Jan 2020

A Study Of Particle-Laden Flows From Meso And Micro-Scale Perspectives, Daniel Guedes De Oliveira

LSU Doctoral Dissertations

Particle-laden flows are investigated numerically from a meso-scale perspective using Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) and from a micro-scale perspective using Particle Resolved Direct Numerical Simulation (PR-DNS). For the former, the dynamics of a pseudo-2D pulsed fluidized bed (PFB) consisting of 400,000 to 800,000 particles was investigated (Chapters 2 and 3). The focus is on the capabilities of CFD-DEM to (1) reproduce pattern formation in these systems and (2) further the understanding of the dynamics of PFB's as a function of pulsation parameters. In Chapter 4, a two-spheres system is investigated with a recently implemented PR-DNS …


Nanoscale Colocalization Of Fluorogenic Probes Reveals The Role Of Oxygen Vacancies In The Photocatalytic Activity Of Tungsten Oxide Nanowires, Meikun Shen, Tianben Ding, Steven T. Hartman, Fudong Wang, Christina Krucylak, Zheyu Wang, Che Tan, Bo Yin, Rohan Mishra, Matthew D. Lew, Bryce Sadtler Jan 2020

Nanoscale Colocalization Of Fluorogenic Probes Reveals The Role Of Oxygen Vacancies In The Photocatalytic Activity Of Tungsten Oxide Nanowires, Meikun Shen, Tianben Ding, Steven T. Hartman, Fudong Wang, Christina Krucylak, Zheyu Wang, Che Tan, Bo Yin, Rohan Mishra, Matthew D. Lew, Bryce Sadtler

Electrical & Systems Engineering Publications and Presentations

Defect engineering is a strategy that has been widely used to design active semiconductor photocatalysts. However, understanding the role of defects, such as oxygen vacancies, in controlling photocatalytic activity remains a challenge. Here, we report the use of chemically triggered fluorogenic probes to study the spatial distribution of active regions in individual tungsten oxide nanowires using super-resolution fluorescence microscopy. The nanowires show significant heterogeneity along their lengths for the photocatalytic generation of hydroxyl radicals. Through quantitative, coordinate-based colocalization of multiple probe molecules activated by the same nanowires, we demonstrate that the nanoscale regions most active for the photocatalytic generation of …


Catalysts For Polymer Membrane Fuel Cells, William E. Mustain, Bryan Pivovar Jan 2020

Catalysts For Polymer Membrane Fuel Cells, William E. Mustain, Bryan Pivovar

Faculty Publications

No abstract provided.


Carbon-Based Artificial Sei Layers For Aqueous Lithium-Ion Battery Anodes, Usha Subramanya, Charleston Chua, Victor Gin He Leong, Ryan Robinson, Gwenlyn Cruz Cabiltes, Prakirti Singh, Bonnie Yip, Anuja Bokare, Folarin Erogbogbo, Dahyun Oh Jan 2020

Carbon-Based Artificial Sei Layers For Aqueous Lithium-Ion Battery Anodes, Usha Subramanya, Charleston Chua, Victor Gin He Leong, Ryan Robinson, Gwenlyn Cruz Cabiltes, Prakirti Singh, Bonnie Yip, Anuja Bokare, Folarin Erogbogbo, Dahyun Oh

Faculty Publications

Replacing flammable organic electrolytes with aqueous electrolytes in lithium-ion batteries (LIB) can greatly enhance the safety of next-generation energy storage systems. With the extended electrochemical stability window of electrolytes, 'water-in-salt' (WIS) electrolytes containing LIB presented significant performance improvements. However, the solubility limits of lithium salts in water restrain the extent of kinetic protection offered by the high salt concentration. Here, we report design strategies of anode structure to improve the cycle life of LIB with WIS electrolytes. We introduced partially graphitic protective carbon layers on anode particles using a versatile coating method. This protective layer not only improved charge transfer …


Load-Balancing Rendezvous Approach For Mobility-Enabled Adaptive Energy-Efficient Data Collection In Wsns, Jian Zhang, Jian Tang, Zhonghui Wang, Feng Wang, Gang Yu Jan 2020

Load-Balancing Rendezvous Approach For Mobility-Enabled Adaptive Energy-Efficient Data Collection In Wsns, Jian Zhang, Jian Tang, Zhonghui Wang, Feng Wang, Gang Yu

Faculty and Student Publications

Copyright © 2020 KSII The tradeoff between energy conservation and traffic balancing is a dilemma problem in Wireless Sensor Networks (WSNs). By analyzing the intrinsic relationship between cluster properties and long distance transmission energy consumption, we characterize three node sets of the cluster as a theoretical foundation to enhance high performance of WSNs, and propose optimal solutions by introducing rendezvous and Mobile Elements (MEs) to optimize energy consumption for prolonging the lifetime of WSNs. First, we exploit an approximate method based on the transmission distance from the different node to an ME to select suboptimal Rendezvous Point (RP) on the …


Revisiting Lightweight Encryption For Iot Applications: Error Performance And Throughput In Wireless Fading Channels With And Without Coding, Yazid M. Khattabi, Mustafa M. Matalgah, Mohammed M. Olama Jan 2020

Revisiting Lightweight Encryption For Iot Applications: Error Performance And Throughput In Wireless Fading Channels With And Without Coding, Yazid M. Khattabi, Mustafa M. Matalgah, Mohammed M. Olama

Faculty and Student Publications

© 2013 IEEE. Employing heavy conventional encryption algorithms in communications suffers from added overhead and processing time delay; and in wireless communications, in particular, suffers from severe performance deterioration (avalanche effect) due to fading. Consequently, a tremendous reduction in data throughput and increase in complexity and time delay may occur especially when information traverse resource-limited devices as in Internet-of-Things (IoT) applications. To overcome these drawbacks, efficient lightweight encryption algorithms have been recently proposed in literature. One of those, that is of particular interest, requires using conventional encryption only for the first block of data in a given frame being transmitted. …


Cooperative Relay Selection For Load Balancing With Mobility In Hierarchical Wsns: A Multi-Armed Bandit Approach, Jian Zhang, Jian Tang, Feng Wang Jan 2020

Cooperative Relay Selection For Load Balancing With Mobility In Hierarchical Wsns: A Multi-Armed Bandit Approach, Jian Zhang, Jian Tang, Feng Wang

Faculty and Student Publications

© 2013 IEEE. Energy efficiency is the major concern in hierarchical wireless sensor networks(WSNs), where the major energy consumption originates from radios for communication. Due to notable energy expenditure of long-range transmission for cluster members and data aggregation for Cluster Head (CH), saving and balancing energy consumption is a tricky challenge in WSNs. In this paper, we design a CH selection mechanism with a mobile sink (MS) while proposing relay selection algorithms with multi-user multi-armed bandit (UM-MAB) to solve the problem of energy efficiency. According to the definition of node density and residual energy, we propose a conception referred to …


Tuning The Size And Composition Of Manganese Oxide Nanoparticles Through Varying Temperature Ramp And Aging Time, Celia Martinez De La Torre, Jasmine H. Grossman, Andrey A. Bobko, Margaret F. Bennewitz Jan 2020

Tuning The Size And Composition Of Manganese Oxide Nanoparticles Through Varying Temperature Ramp And Aging Time, Celia Martinez De La Torre, Jasmine H. Grossman, Andrey A. Bobko, Margaret F. Bennewitz

Faculty & Staff Scholarship

Manganese oxide (MnO) nanoparticles (NPs) can serve as robust pH-sensitive contrast agents for magnetic resonance imaging (MRI) due to Mn2+ release at low pH, which generates a ~30 fold change in T1 relaxivity. Strategies to control NP size, composition, and Mn2+ dissolution rates are essential to improve diagnostic performance of pH-responsive MnO NPs. We are the first to demonstrate that MnO NP size and composition can be tuned by the temperature ramping rate and aging time used during thermal decomposition of manganese(II) acetylacetonate. Two different temperature ramping rates (10°C/min and 20°C/min) were applied to reach 300°C and NPs were aged …


Investigating New Methods To Develop Perovskite Solar Cells, Amani Hussain Alfaifi Jan 2020

Investigating New Methods To Develop Perovskite Solar Cells, Amani Hussain Alfaifi

Electronic Theses and Dissertations

Discovering the potential of organic-inorganic metal halide perovskites (MHP) as a harvesting material in solar cells has strongly affected the research direction in solar energy. The fascinating optical and electronic properties offered by MHP combined with tremendous effort from scientists around the world have improved the efficiency to about 25% in a decade.

In the first part of the dissertation, we studied the lamination process as a new fabrication method for producing self-encapsulated perovskite solar cells based on laminating half stacks,as opposed to the conventional layer-by-layer method. Our work focused on optimizing the lamination process of complex triple cations perovskite …


Experimental Investigation Of Low-Voltage Silicon Carbide (Sic) Semiconductor Devices For Power Conversion Applications, Saleh Salem H. Alharbi Jan 2020

Experimental Investigation Of Low-Voltage Silicon Carbide (Sic) Semiconductor Devices For Power Conversion Applications, Saleh Salem H. Alharbi

Electronic Theses and Dissertations

Enhancing the performance and efficiency of power converter systems requires fast-switching power devices with considerably low switching and conduction losses. Silicon (Si) semiconductor devices are the essential components in electronic converter designs, and their behaviors and switching characteristics determine the system’s overall performance and efficiency. These conventional Si devices are nearing to hit their physical and operational limits in meeting power converter requirements with respect to high temperature and large voltage conditions. However, silicon carbide (SiC) power devices enable greater converter efficiency and better power density, particularly under hard switching frequencies and high output voltages due to their outstanding material …


Experimental Evaluation Of Medium-Voltage Cascode Gallium Nitride (Gan) Devices For Bidirectional Dc–Dc Converters, Salah Salem H. Alharbi Jan 2020

Experimental Evaluation Of Medium-Voltage Cascode Gallium Nitride (Gan) Devices For Bidirectional Dc–Dc Converters, Salah Salem H. Alharbi

Electronic Theses and Dissertations

As renewable energy sources, such as photovoltaic (PV) cells and wind turbines, are rapidly implemented in DC microgrids, energy storage systems play an increasingly significant role in ensuring uninterrupted power supply and in supporting the reliability and stability of microgrid operations. Power electronics, especially bidirectional DC–DC converters, are essential parts in distributed energy storage and alternative energy systems because of their grid synchronization, DC power management, and bidirectional power flow capabilities. While there is increasing demand for more efficient, compact, and reliable power converters in numerous applications, most existing power converters are hindered by traditional silicon (Si) based semiconductors, which …


Enhancing Protection Of Vehicle Drivers And Road Safety By Deploying Adas And Facial Features Pattern Analysis (Ffpa) Technologies, Raymond Sze Wai Fu, Xueying Wang, Antonio Wong, Chi-Wing Tsang Jan 2020

Enhancing Protection Of Vehicle Drivers And Road Safety By Deploying Adas And Facial Features Pattern Analysis (Ffpa) Technologies, Raymond Sze Wai Fu, Xueying Wang, Antonio Wong, Chi-Wing Tsang

Faculty of Science & Technology (THEi)

The latest technology associated with Intelligent Transportation Systems (ITS) have been designed with the aim to minimize the numbers of person injury in road accidents and improve the overall road safety. The driver behavior is one major concern in many accidents in HK urban road links. In particular, the driver's attitudes, such as fatigue, drowsiness and concentration are the major causes to road accidents. It will affect the driver's ability and decisions in properly controlling their vehicles. Very often, this kind of driver distraction is particularly obvious when driving after 2 to 3 hours from most research sources. In the …


Seed-Mediated Crystallization Of Charge-Transfer Complexes And Their Applications For Gas Sensing, Xuecheng Yu Jan 2020

Seed-Mediated Crystallization Of Charge-Transfer Complexes And Their Applications For Gas Sensing, Xuecheng Yu

Wayne State University Dissertations

The dissertation focused on controllable seed-mediated nucleaton of charge transfer complex, namely tetrathiafulvalene bromide ((TTF)Br) and Krogmann’s salts (KCP), and their applications in sensing. On gold nanoparticle (AuNP) decorated highly oriented pyrolytic graphite (HOPG) substrate, the presence of AuNP promotes the formation of charge transfer salt nanowires. The size of these nanowires, both (TTF)Br and KCP, were found to be confined by the size of AuNPs, shown by SEM and AFM characterization. On micro-disk electrodes, charge transfer salt nanowires were found to own a linear time dependency, by both SEM and in-situ optical microscopy. The micro-disk electrodes promoted higher crystallization …