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Car Wash Complex – Object Of Harmful Impact On Water Resources, M. Radkevich, K. Shipilova, M. Abdukodirova, O. Pochugevski Dec 2020

Car Wash Complex – Object Of Harmful Impact On Water Resources, M. Radkevich, K. Shipilova, M. Abdukodirova, O. Pochugevski

Irrigation and Melioration

Deals with the problem of the impact of car wash complexes in the city of Tashkent on water resources. The analysis of the technological process of washing and a sociological survey of car owners and employees of car washes revealed the average amount of water used per car wash per year, as well as the amount of harmful substances entering the sewer network of the city of Tashkent. Calculations have shown that the annual water consumption only for passenger cars in Tashkent is about 4.34 million m3, and the wastewater is not properly treated. From one car wash …


Incorporating Pacific Ocean Climate Information To Enhance The Tree-Ring Based Streamflow Reconstruction Skill, Saria Bukhary, Ajay Kalra, Sajjad Ahmad Dec 2020

Incorporating Pacific Ocean Climate Information To Enhance The Tree-Ring Based Streamflow Reconstruction Skill, Saria Bukhary, Ajay Kalra, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

The Sacramento River Basin (SRB) and the San Joaquin River Basin (JRB) have a history of recurring droughts. Both are important for California, being the crucial source of water supply. The available instrumental records may not depict the long-term hydrologic variability encompassing the duration and frequency of the historic low flow events. Thus, streamflow reconstruction becomes important in the current scenario of climatic alteration, escalating population and growing water needs. Studies have shown that Pacific Decadal Oscillation (PDO), Southern Oscillation Index (SOI), and Pacific Ocean sea surface temperature (SST) influence the precipitation and streamflow volumes of southwestern United States, particularly …


Investigation Of The Moisture Binding Forms In Plant Raw Materials And Thermal Characteristics Determination, Tojiniso Raxmanova, Shaxnoza Sultanova, Jasur Safarov, Esra Capanoglu Dec 2020

Investigation Of The Moisture Binding Forms In Plant Raw Materials And Thermal Characteristics Determination, Tojiniso Raxmanova, Shaxnoza Sultanova, Jasur Safarov, Esra Capanoglu

Technical science and innovation

In this article, the forms of moisture connection and the thermal characteristics of plant materials are studied. Rosehip and hawthorn fruits were chosen as the object of research. In the heat analyzer, a decrease in the mass of the product and an increase in temperature were found when the temperature was controlled in a certain gas environment. The curves of the dependence of the dog rose and hawthorn samples on the mass and temperature are given. DTA-1/10 galvanometer sensitivity; sensitivity of the DTG-1/5 galvanometer; the maximum heating temperature is 300° С and the rate of change of the furnace heating …


Effect Of Reaction Conditions On Cu⁃Catalyzed Co2 Electroreduction, Chang Zhu, Wei Chen, Yan-Fang Song, Xiao Dong, Gui-Hua Li, Wei Wei, Yu-Han Sun Dec 2020

Effect Of Reaction Conditions On Cu⁃Catalyzed Co2 Electroreduction, Chang Zhu, Wei Chen, Yan-Fang Song, Xiao Dong, Gui-Hua Li, Wei Wei, Yu-Han Sun

Journal of Electrochemistry

Electrochemical conversion of carbon dioxide (CO2) driven by renewable electricity that can meet both carbon emission reduction and renewable energy utilization has been rapidly developed in recent years. Copper (Cu) catalyst has long been a promising candidate for CO2 electroreduction applications because of its natural abundance and specific capability of producing a substantial amount of C2 products. However, various metallic Cu electrodes reported have been significantly influenced by the adsorption of certain cation/anion ions, resulting in wide-span catalytic activities and selectivity for various products. In addition, a recent report demonstrated that by virtue of gas-diffusion flow cell …


Recent Advances And Machine Learning Techniques On Sickle Cell Disease, Noorh H. Alharbi, Rana O. Bameer, Shahad S. Geddan, Hajar M. Alharbi Dec 2020

Recent Advances And Machine Learning Techniques On Sickle Cell Disease, Noorh H. Alharbi, Rana O. Bameer, Shahad S. Geddan, Hajar M. Alharbi

Future Computing and Informatics Journal

Sickle cell disease is a severe hereditary disease caused by an abnormality of the red blood cells. The current therapeutic decision-making process applied to sickle cell disease includes monitoring a patient’s symptoms and complications and then adjusting the treatment accordingly. This process is time-consuming, which might result in serious consequences for patients’ lives and could lead to irreversible disease complications. Artificial intelligence, specifically machine learning, is a powerful technique that has been used to support medical decisions. This paper aims to review the recently developed machine learning models designed to interpret medical data regarding sickle cell disease. To propose an …


A Study On An Accurate Underwater Location Of Hybrid Underwater Gliders Using Machine Learning, Sang-Ki Jeong, Hyeung-Sik Choi, Dea-Hyung Ji, Mai The Vu, Joon-Young Kim, Sung Min Hong, Hyun Joon Cho Dec 2020

A Study On An Accurate Underwater Location Of Hybrid Underwater Gliders Using Machine Learning, Sang-Ki Jeong, Hyeung-Sik Choi, Dea-Hyung Ji, Mai The Vu, Joon-Young Kim, Sung Min Hong, Hyun Joon Cho

Journal of Marine Science and Technology–Taiwan

A hybrid underwater glider (HUG) is marine observation equipment that consumes a small amount of energy and offers greater range and navigation times. To achieve reduced energy consumption, however, the HUG uses imprecise navigation sensors, such as mems-type GPS and AHRS, resulting in inaccurate coordination. This study makes a new attempt on the application of machine learning algorithms in a way that complements sensor data errors to improve navigation performance. The proposed algorithm was used to a simulation of the HUG’s navigation and control system, after which the updated heading angle was decided by using the previous position data and …


Biogas Production Of Lignite And Variation Characteristics Of Cations In Liquid Phase System, Zhao Han, He Huan, Wang Jiangze, Song Yanli, Niu Jianglu, Chen Linyong, Guo Xin, Liu Jian, Guan Jiadong, Yuan Xuefang Dec 2020

Biogas Production Of Lignite And Variation Characteristics Of Cations In Liquid Phase System, Zhao Han, He Huan, Wang Jiangze, Song Yanli, Niu Jianglu, Chen Linyong, Guo Xin, Liu Jian, Guan Jiadong, Yuan Xuefang

Coal Geology & Exploration

Liupan Shan lies between the Tibetan plateau and Ordos block and has been under the remote effect of the northeastward extension of the Tibetan plateau. The former research about the uplift of Liupan Shan mainly focused on the petrology, structural deformation or tectonic evolution study from the Cretaceous to early period of Cenozoic. However, the Late Pleistocene geological study closely connected with the human activities was rarely mentioned. In this study, we carried out systematic sedimentary research in the Qingshuihe basin adjacent to the Liupan Shan tectonic belt, re-determine the sedimentary sequence at first, then reverse the uplift history of …


Water Availability For Cannabis In Northern California: Intersections Of Climate, Policy, And Public Discourse, Betsy Morgan, Kaitlyn Spangler, Jacob Stuivenvolt-Allen, Christina N. Morrisett, Mark W. Brunson, Shih-Yu Simon Wang, Nancy Huntly Dec 2020

Water Availability For Cannabis In Northern California: Intersections Of Climate, Policy, And Public Discourse, Betsy Morgan, Kaitlyn Spangler, Jacob Stuivenvolt-Allen, Christina N. Morrisett, Mark W. Brunson, Shih-Yu Simon Wang, Nancy Huntly

Biology Faculty Publications

Availability of water for irrigated crops is driven by climate and policy, as moderated by public priorities and opinions. We explore how climate and water policy interact to influence water availability for cannabis (Cannabis sativa), a newly regulated crop in California, as well as how public discourse frames these interactions. Grower access to surface water covaries with precipitation frequency and oscillates consistently in an energetic 11–17 year wet-dry cycle. Assessing contemporary cannabis water policies against historic streamflow data showed that legal surface water access was most reliable for cannabis growers with small water rights ( < 600 m3) and …


4d Printing Shape Memory Polymers For Biomedical Applications, Kathleen Pieri Dec 2020

4d Printing Shape Memory Polymers For Biomedical Applications, Kathleen Pieri

Dissertations - ALL

The development of 3D printing techniques using shape-memory polymers (SMPs) hascreated potentials for creating dynamic, three-dimensional structures that can be produced rapidly and be customized for specific and complex architectures. These qualities have made 3D printing a popular fabrication method for future SMP parts and devices. While important information about is known about the effects of printing parameters on 3D printed SMPs, there remains a gap in the understanding of these parameters on fundamental shape memory properties. Understanding the shape memory behavior of the SMPs post-printing can implicate potential advantages or weaknesses in using these materials in biomedical applications. Furthermore, …


Wrinkling Patterns On Curved Surface With Gradient Curvature Under Compression, Xiaoxiao Zhang Dec 2020

Wrinkling Patterns On Curved Surface With Gradient Curvature Under Compression, Xiaoxiao Zhang

Dissertations - ALL

This work focuses on understanding the wrinkling patterns on a curved surface, i.e., tori and cones, with varying curvatures and global deformation. By tuning the geometry confine-ment and material properties, we can control the surface morphologies in these systems which can potentially be applied to wide applications in bio-inspired devices, microfluidic, and optical.

First, we investigate the wrinkles on a tri-layer torus consisting of an expanding thin outer layer, an intermediate soft layer, and an inner core with a tunable shear modulus. This study is inspired by pattern formations and evolutions in developmental biology, such as follicle pattern formation during …


Modeling And Simulation Of Morphological Instabilities In Thin Elastic Solids, Junbo Chen Dec 2020

Modeling And Simulation Of Morphological Instabilities In Thin Elastic Solids, Junbo Chen

Dissertations - ALL

The study of morphological instabilities in thin solids, such as buckling of thin shells and wrinkling of thin sheets, is of growing interest to a number of academic disciplines including en-gineering, physics, biology, and many others. For example, buckling has traditionally been re-garded as an unfavorable phenomenon in engineering design, but emerging technologies con-sider such behavior as an opportunity for novel functionality. The formation of wrinkle patterns on thin sheets has also emerged rapidly as canonical problems to investigate pattern formation in the physics community. The nonlinearities of the post-buckling behaviors encountered in these problems make theoretical analysis a challenging …


Cardiac Organoid Technology And Computational Processing Of Cardiac Physiology For Advanced Drug Screening Applications, Plansky Hoang Dec 2020

Cardiac Organoid Technology And Computational Processing Of Cardiac Physiology For Advanced Drug Screening Applications, Plansky Hoang

Dissertations - ALL

Stem cell technology has gained considerable recognition since its inception to advance disease modeling and drug screening. This is especially true for tissues that are difficult to study due to tissue sensitivity and limited regenerative capacity, such as the heart. Previous work in stem cell-derived cardiac tissue has exploited how we can engineer biologically functional heart tissue by providing the appropriate external stimuli to facilitate tissue development. The goal of this dissertation is to explore the potentials of stem cell cardiac organoid models to recapitulate heart development and implement analytical computational tools to study cardiac physiology. These new tools were …


Solar Photovoltaic Performance Monitoring: A Bibliometric Review, Research Gaps And Opportunities, Javed Sayyad, Paresh Nasikkar Dec 2020

Solar Photovoltaic Performance Monitoring: A Bibliometric Review, Research Gaps And Opportunities, Javed Sayyad, Paresh Nasikkar

Library Philosophy and Practice (e-journal)

Electrical power generation has been revolutionized by growing demand and use of Renewable Energy (RE) sources such as Solar Photovoltaic (SPV) as the main electricity source in modern times. The main objective of this bibliometric analysis is to understand the scope of the literature available for SPV performance characterization. This detailed reviewed was performed on the documents related to SPV research considering all the subject categories from Scopus and Web of Science (WoS) databases. The patterns for the particular set of keywords were broke down with the recuperated outcomes from Scopus database in the language, publication type, year of publication, …


Effect Of Microcapsule Content On Diels-Alder Room Temperature Self-Healing Thermosets., Sadella C Santos, John J La Scala, Giuseppe R Palmese Dec 2020

Effect Of Microcapsule Content On Diels-Alder Room Temperature Self-Healing Thermosets., Sadella C Santos, John J La Scala, Giuseppe R Palmese

Henry M. Rowan College of Engineering Departmental Research

A furan functionalized epoxy-amine thermoset with an embedded microcapsule healing system that utilizes reversible Diels-Alder healing chemistry was used to investigate the influence of microcapsule loading on healing efficiency. A urea-formaldehyde encapsulation technique was used to create capsules with an average diameter of 150 µm that were filled with a reactive solution of bismaleimide in phenyl acetate. It was found that optimum healing of the thermoset occurred at 10 wt% microcapsule content for the compositions investigated. The diffusion of solvent through the crack interface and within fractured samples was investigated using analytical diffusion models. The decrease in healing efficiency at …


Advanced Thermal Characterization And Temperature Control To Enable The Next Generation Of Micro-Electronic Technologies, Assaad El Helou Dec 2020

Advanced Thermal Characterization And Temperature Control To Enable The Next Generation Of Micro-Electronic Technologies, Assaad El Helou

Mechanical Engineering Research Theses and Dissertations

In the electronics world, self-heating is an inevitable by-product of electrical activation that has a major impact on device performance and reliability. Thermal technologies have been in constant development to effectively dissipate the generated heat and keep device operation temperatures within reliable limits. Moreover, thermal characterization technologies have been implemented to understand the thermal performance within microelectronic sys- tems, but not without facing experimental and numerical challenges. This work presents ad- vanced thermal investigations, both experimental and numerical, that are adapted and most suited for emerging micro-electronic technologies. Initially, the main experimental and numerical modeling challenges faced in the thermal …


Microparticle Propulsion For In Vivo Navigation, Louis Rogowski Dec 2020

Microparticle Propulsion For In Vivo Navigation, Louis Rogowski

Mechanical Engineering Research Theses and Dissertations

Microscale propulsion impacts a diverse array of fields, with simplistic microrobots allowing for novel innovations in microscale surgery and drug delivery. Propulsion at the microscale is constrained by physics, with time-reversal and geometric symmetries limiting available propulsion mechanisms. However, certain fluid environments and surface coatings allow for the propulsion of microparticles through externally applied magnetic fields. Presented here is a detailed analysis of microparticles propelling using spontaneous symmetry breaking, flagella surface coatings, and multi-modal actuation mechanisms. Spontaneous symmetry breaking in nonlinearly viscoelastic fluids is presented for the first time in literature, with two equal and opposite propulsion states existing along …


The Effect Of Surface Air Entrapment On Oscillating Fin Flow At Intermediate Reynolds Number, Nicholas Davis Dec 2020

The Effect Of Surface Air Entrapment On Oscillating Fin Flow At Intermediate Reynolds Number, Nicholas Davis

Mechanical Engineering Research Theses and Dissertations

Oscillating fin flow has been a subject of study due to its simplicity and similarity to aquatic propulsion methods found in nature. At intermediate Reynolds numbers, in the range of 10 to 1000, drag tends to have a larger impact than at higher Reynolds numbers and the boundary layer thickness on the fin surface tends to be larger, which can alter the vortices shed during oscillation. To attempt to reduce these effects, an apparent slip condition may be placed on the surface of the fin. In this investigation, entrapment of pneumatically supplied air at a perforated fin surface was used …


Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee Dec 2020

Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee

Multidisciplinary Studies Theses and Dissertations

Accomplishing slow translocation speed with high sensitivity has been the greatest mission for solid-state nanopore (SSN) to electrically detect nucleobases in single-stranded DNA (ssDNA). In this study, a method to detect nucleobases in ssDNA using a SSN is introduced by considerably slowing down the translocation speed and effectively increasing its sensitivity. The ultra-thin titanium dioxide (TiO2) coated hexagonal boron nitride (h-BN) nanopore was fabricated, along with an ionic-liquid [bmim][PF6]/2.0 M KCl aqueous (cis/trans) interfacial system, to increase both the spatial and the temporal resolutions. As the ssDNA molecules entered the nanopore, a …


Modeling Residence Time Distribution Of Chromatographic Perfusion Resin For Large Biopharmaceutical Molecules: A Computational Fluid Dynamic Study, Kevin Vehar Dec 2020

Modeling Residence Time Distribution Of Chromatographic Perfusion Resin For Large Biopharmaceutical Molecules: A Computational Fluid Dynamic Study, Kevin Vehar

KGI Theses and Dissertations

The need for production processes of large biotherapeutic particles, such as virus-based particles and extracellular vesicles, has risen due to increased demand in the development of vaccinations, gene therapies, and cancer treatments. Liquid chromatography plays a significant role in the purification process and is routinely used with therapeutic protein production. However, performance with larger macromolecules is often inconsistent, and parameter estimation for process development can be extremely time- and resource-intensive. This thesis aimed to utilize advances in computational fluid dynamic (CFD) modeling to generate a first-principle model of the chromatographic process while minimizing model parameter estimation's physical resource demand. Specifically, …


Stress Relaxation In Orthodontic Aligner Plastics; An In Vitro Comparison Study, Kristopher J. Keller Dec 2020

Stress Relaxation In Orthodontic Aligner Plastics; An In Vitro Comparison Study, Kristopher J. Keller

Theses & Dissertations

The purpose of this study was to ascertain if repeated stresses from extension cycling would result in accumulated damage in aligner materials and affect force delivery. A secondary goal was to identify potential differences in mechanical behavior present among orthodontic aligner polymers. Four thermoplastic polymers (Essix ACE, Taglus, Zendura, and Zendura FLX) were thermoformed, cut into strips, and extension cycled to 0.4 millimeters in a 37C water bath. Force decay, maximum and minimum force, and elastic modulus were measured during cycling. Additional samples were subjected to controlled tension until failure, allowing the measurement of yield strength, ultimate strength, and elastic …


A Survey On Underwater Bionic Electric Perception, Guangming Xie, Junzheng Zheng, Wang Chen Dec 2020

A Survey On Underwater Bionic Electric Perception, Guangming Xie, Junzheng Zheng, Wang Chen

Journal of System Simulation

Abstract: Sensing and detection technologies for underwater robots in complex underwater environments have been urgently needed.Weakly electric fields-based underwater bionic electric perception is a promising technical route.A kind of fish in nature,called weakly electric fish,can perceive their surrounding environment and other creatures through the varied electric field generated by themselves.Inspired by the electric fish,researchers have focused on the principle and methods of underwater perception based on weakly electric fields and the applications for intelligent underwater robots.The biological mechanism of weakly electric fish,the modeling and perception theory of underwater electric field,the underwater electric perception technology,and their applications are reviewed,and the …


Analyzing Dispatching Wave Policies For E-Commerce Logistics Based On The Multi-Agent-Based Simulation, Zhiqiang Niu, Chaoyang Li, Hongyu Dong, Zhang Feng, Lingyun Meng, Tong Lu, Shengnan Wu Dec 2020

Analyzing Dispatching Wave Policies For E-Commerce Logistics Based On The Multi-Agent-Based Simulation, Zhiqiang Niu, Chaoyang Li, Hongyu Dong, Zhang Feng, Lingyun Meng, Tong Lu, Shengnan Wu

Journal of System Simulation

Abstract: To provide superior on-line shopping experiences and maintain sustained profitability,e-commerce logistics companies need design an effective dispatching wave policy strategy to handle the tradeoff between the advantage of economies of scale and fast-pace delivery services.A multi-agent-based simulation framework is proposed,where business processes in logistics are built as different nodes in the simulation network.Case studies are conducted to test the order delivery process with various wave strategies in the Beijing metropolitan area.Experimental results show that situation-dependent wave strategies are sensitive to different patterns of online shopping demands.


Nanoscale Material Interaction With Multicellular 3d Cancer Culture, Emilie Darrigues Dec 2020

Nanoscale Material Interaction With Multicellular 3d Cancer Culture, Emilie Darrigues

Theses and Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer, it is difficult to diagnose, often recurs, has high resistance to chemotherapies, and can be marked by advanced metastatic stages. There is an urgent need to fill the knowledge on nanoparticle penetration, diffusion, and cellular interaction in the context of adaptive PDAC tumor microenvironment to allow the development of new imaging and therapeutic supports. Traditionally, cancer-treating nanoparticles have been engineered and tested on 2D cell cultures, but several studies indicate that this in vitro model does not mimic tumor features closely enough. In contrast, 3D culture models offer …


Interface Engineering Of Materials For Energy And Biological Applications, Ardalan Chaichi Dec 2020

Interface Engineering Of Materials For Energy And Biological Applications, Ardalan Chaichi

LSU Doctoral Dissertations

Interface interactions are generally classified into solid-liquid, solid-gas, solid-vacuum, liquid-gas, light-matter and electron-matter categories. Surface morphological studies as well as surface chemical reactions can be studied in various types of complex systems thanks to technological advances in materials characterization methods. By employing interface engineering in different applications, it is possible to control electrical, chemical, mechanical, optical and biological properties of materials. Accordingly, we have applied interface engineering in three different areas of energy materials, biomaterials and surface imaging. As a result, firstly, we have introduced a high intensity light flash-based method on engineered substrates for delamination of reduced graphene oxide …


Experimental And Modeling Of Biomass Char Gasification, Ruochen Wu Dec 2020

Experimental And Modeling Of Biomass Char Gasification, Ruochen Wu

Theses and Dissertations

This investigation provides a comprehensive experimental dataset and kinetic model for biomass gasification, over a wide temperature range (1150-1350 °Ï¹) in CO2, H2O and the combination of these two reactant gases over the mole fraction ranges of 0 to 0.5 for H2O and 0 to 0.9 for CO2. The data come from a unique experimental facility that tracks continuous mass loss rates for poplar wood, corn stover and switchgrass over the size range of 6-12.5 mm. In addition, the data include char size, shape, surface and internal temperature and discrete measurements of porosity, total surface area, pore size distribution and …


Inter-Cross De-Modulated Refractive Index And Temperature Sensor By An Etched Multi-Core Fiber Of A Mzi Structure, Farhan Mumtaz, Yutang Dai, Muhammad Aqueel Ashraf Dec 2020

Inter-Cross De-Modulated Refractive Index And Temperature Sensor By An Etched Multi-Core Fiber Of A Mzi Structure, Farhan Mumtaz, Yutang Dai, Muhammad Aqueel Ashraf

Electrical and Computer Engineering Faculty Research & Creative Works

We present a relative sensitivity of in-fiber inter-cross demodulation of a Mach-Zehnder interferometer (MZI) based on an etched multi-core fiber (eMCF). The sensor can measure the external refractive index (RI) and temperature with a large fringe visibility of 15 dB. It is tuned using a simple technique of slow chemical etching. When the outer cores of MCF will be exposed to the surrounding, a large difference of relative effective RI is observed, which enhances the sensitivity of the sensor. The sensor's wavelength and intensity responses have displayed that it can function with three different inter-cross-demodulation phenomena. A superior RI sensitivity …


Feasibility Of Continuous Fever Monitoring Using Wearable Devices, Benjamin L. Smarr, Kirstin Aschbacher, Sarah M. Fisher, Anoushka Chowdhary, Stephan Dilchert, Karena Puldon, Adam Rao, Frederick M. Hecht, Ashley E. Mason Dec 2020

Feasibility Of Continuous Fever Monitoring Using Wearable Devices, Benjamin L. Smarr, Kirstin Aschbacher, Sarah M. Fisher, Anoushka Chowdhary, Stephan Dilchert, Karena Puldon, Adam Rao, Frederick M. Hecht, Ashley E. Mason

Publications and Research

Elevated core temperature constitutes an important biomarker for COVID-19 infection; however, no standards currently exist to monitor fever using wearable peripheral temperature sensors. Evidence that sensors could be used to develop fever monitoring capabilities would enable large-scale health-monitoring research and provide high-temporal resolution data on fever responses across heterogeneous populations. We launched the TemPredict study in March of 2020 to capture continuous physiological data, including peripheral temperature, from a commercially available wearable device during the novel coronavirus pandemic. We coupled these data with symptom reports and COVID-19 diagnosis data. Here we report findings from the first 50 subjects who reported …


Probing The Impacts Of Ultra-Low Platinum Loadings On Membrane Degradation Mechanisms, Andre J. Spears Dec 2020

Probing The Impacts Of Ultra-Low Platinum Loadings On Membrane Degradation Mechanisms, Andre J. Spears

Nanoscience and Microsystems ETDs

Membrane chemical degradation is one of many factors that can impact fuel cell durability. The fuel cell’s performance and lifetime heavily depends on the membrane and its ability to maintain chemical and mechanical integrity. In Nafion® membranes, hydroxyl radicals are the primary cause of chemical membrane degradation as they attack the membrane’s polymer structure. Radical formation can ensue via peroxide decomposition at the cathode or gases reacting on Pt particles or contaminants like Fe (a fenton's reagent) within the membrane. As radicals attack the membrane’s polymer structure the membrane thins, and fluoride and sulfate ions are released. This consequently …


Copper Electrodeposition In Full Wafer Thickness Through-Silicon Vias, Rebecca P. Schmitt Dec 2020

Copper Electrodeposition In Full Wafer Thickness Through-Silicon Vias, Rebecca P. Schmitt

Chemical and Biological Engineering ETDs

Through-silicon vias (TSVs) are a key interconnect technology for advanced packaging of microelectronic devices, and full wafer thickness TSVs are required for certain microelectromechanical systems (MEMS) applications. In this work, electrolytes containing copper sulfate, an acid, chloride, and Tetronic 701 suppressor were implemented for Cu filling of high aspect ratio (10:1), full wafer thickness TSVs. For each electrolyte system, rotating disk electrode voltammetry was used to identify a voltage range for bottom-up Cu filling in the TSVs. Die level feature filling was performed using voltage ramping, which moved active deposition through the vias to yield void-free Cu features. During voltage-controlled …


Solar Insolation Micro-Forecasts Using Longwave Infrared Sensors And Artificial Intelligence, Anthony R. Menicucci Dec 2020

Solar Insolation Micro-Forecasts Using Longwave Infrared Sensors And Artificial Intelligence, Anthony R. Menicucci

Mechanical Engineering ETDs

Solar Insolation Micro-Forecasts (SIMF) are used by Independent Service Operators (ISOs) and other grid operators to maintain constant and stable electrical grid frequency, voltage, power factor and waveform across their transmission infrastructure. Intermittent, thick, dense and typically cumulus clouds negatively impact the electrical grid by quickly turning on and off power production from large solar photovoltaic (PV) fields, causing grid stability problems between generation and load. Forecasting insolation values over large PV fields allows operators the chance to anticipate and proactively implement mitigation strategies like engaging spinning reserve from gas turbines, deploying generators, buying power in the spot market, and …