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Full-Text Articles in Engineering

Development Of Experimental And Numerical Methods For Investigations Of High-Octane Fuels In Heavy-Duty Applications, Jared James Zeman Jul 2021

Development Of Experimental And Numerical Methods For Investigations Of High-Octane Fuels In Heavy-Duty Applications, Jared James Zeman

Master's Theses (2009 -)

Increasingly stringent emissions regulations has threatened the existence of the internal combustion (IC) engine. In some transportation sectors, non-IC engine powertrains have the potential to be a logical solution. However, in the heavy-duty sector, the IC engine is predicted to remain the dominant propulsion method for the foreseeable future. With ever-increasing demand for heavy-duty power generation platforms, the primary focus for the development of the future heavy-duty IC engine needs to be on increasing engine efficiency and the adoption of lowlife-cycle carbon, clean burning fuels, e.g. methanol. The fuel ignition properties of these fuels, e.g. high octane, cause difficulties when …


Creation And Application Of Various Tools For The Reconstruction, Curation, And Analysis Of Genome-Scale Models Of Metabolism, Wheaton L. Schroeder Jun 2021

Creation And Application Of Various Tools For The Reconstruction, Curation, And Analysis Of Genome-Scale Models Of Metabolism, Wheaton L. Schroeder

Department of Chemical and Biomolecular Engineering: Theses and Student Research

Systems biology uses mathematics tools, modeling, and analysis for holistic understanding and design of biological systems, allowing the investigation of metabolism and the generation of actionable hypotheses based on model analyses. Detailed here are several systems biology tools for model reconstruction, curation, analysis, and application through synthetic biology. The first, OptFill, is a holistic (whole model) and conservative (minimizing change) tool to aid in genome-scale model (GSM) reconstructions by filling metabolic gaps caused by lack of system knowledge. This is accomplished through Mixed Integer Linear Programming (MILP), one step of which may also be independently used as an additional curation …


Rapid Development Technology Of Virtual Maintenance Training Simulation Model For Aviation Equipment, Rongqiang Li, Aibing Wen, Bin Hua, Jiajun Li, Jiang Bing Jun 2021

Rapid Development Technology Of Virtual Maintenance Training Simulation Model For Aviation Equipment, Rongqiang Li, Aibing Wen, Bin Hua, Jiajun Li, Jiang Bing

Journal of System Simulation

Abstract: Taking the practical application of the aircraft virtual maintenance training as the demand, the basic development process and technical means of the aircraft virtual maintenance training simulation model are analyzed, which solves the technical bottleneck in the popularization and application of the large-scale engineering. Aiming at the crucial problems such as the low efficiency in the development of maintenance training simulation model and the difficulties in updating the model, a rapid development process to support the large-scale engineering applications is proposed. The principles and implementation ways of three key technologies supporting the rapid development of virtual maintenance training simulation …


Selective Neural Stimulation By Leveraging Electrophysiological Diversity And Using Alternative Stimulus Waveforms, Bemin Ghobreal May 2021

Selective Neural Stimulation By Leveraging Electrophysiological Diversity And Using Alternative Stimulus Waveforms, Bemin Ghobreal

Dissertations

Efforts on finding the principle mechanism for selective neural stimulation have concentrated on segregating the neurons based on their size and other geometric factors. However, neuronal subtypes found in different parts of the nervous system also differ in their electrophysiological properties. The primary objective of this study is to investigate the feasibility of selective activation of neurons by leveraging the diversity seen in passive and active membrane properties.

Using both a local membrane model and an axon model based on the CRRSS, the diversity of electrophysiological properties is simulated by varying four model parameters (membrane leakage-Gleak and capacitance-Cm, temperature coefficient-Ktemp, …


Computational Design Of Nonlinear Stress-Strain Of Isotropic Materials, Askhad M.Polatov, Akhmat M. Ikramov, Daniyarbek Razmukhamedov May 2021

Computational Design Of Nonlinear Stress-Strain Of Isotropic Materials, Askhad M.Polatov, Akhmat M. Ikramov, Daniyarbek Razmukhamedov

Chemical Technology, Control and Management

The article deals with the problems of numerical modeling of nonlinear physical processes of the stress-strain state of structural elements. An elastoplastic medium of a homogeneous solid material is investigated. The results of computational experiments on the study of the process of physically nonlinear deformation of isotropic elements of three-dimensional structures with a system of one- and double-periodic spherical cavities under uniaxial compression are presented. The influence and mutual influence of stress concentrators in the form of spherical cavities, vertically located two cavities and a horizontally located system of two cavities on the deformation of the structure are investigated. Numerical …


Modeling And Monitoring Of Water Quantity And Quality In Permeable Pavement Systems Using Geophysical Equipment, Abby Klimowicz May 2021

Modeling And Monitoring Of Water Quantity And Quality In Permeable Pavement Systems Using Geophysical Equipment, Abby Klimowicz

Honors Scholar Theses

Permeable pavements are a type of low impact development (LID) that reduces runoff by increasing the permeability of developed surfaces. Less runoff helps protect the surrounding ecosystems from erosion and pollution. Without pools of accumulating runoff, the potential for the development of ice on roads and parking lots is also decreased. However, sufficient research on the movement of water and the ions dissolved in it through the permeable pavement system has not been completed. In this study, geophysical equipment was used to observe how moisture, measured as volumetric water content (VWC), and ions, approximated by electrical conductivity, pass through constructed …


A Review Of Harmful Algal Bloom Prediction Models For Lakes And Reservoirs, Jade Snyder Echard May 2021

A Review Of Harmful Algal Bloom Prediction Models For Lakes And Reservoirs, Jade Snyder Echard

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Anthropogenic activity has led to eutrophication in water bodies across the world. This eutrophication promotes blooms, cyanobacteria being among the most notorious bloom organisms. Cyanobacterial blooms (more commonly referred to as harmful algal blooms (HABs)) can devastate an ecosystem. Cyanobacteria are resilient microorganisms that have adapted to survive under a variety of conditions, often outcompeting other phytoplankton. Some species of cyanobacteria produce toxins that ward off predators. These toxins can negatively affect the health of the aquatic life, but also can impact animals and humans that drink or come in contact with these noxious waters. Although cyanotoxin’s effects on humans …


3d Printable And Computational Models Of The Bone Marrow Mechanical Environment, Alexander Regner May 2021

3d Printable And Computational Models Of The Bone Marrow Mechanical Environment, Alexander Regner

Boise State University Theses and Dissertations

Aged individuals and astronauts experience bone loss despite rigorous physical activity. Bone mechanoresponse is in part regulated by mesenchymal stem cells (MSCs). We reported that daily low intensity vibration (LIV) restores MSC proliferation in senescence and simulated microgravity models, suggesting reduced mechanical signal delivery to MSCs likely contributes to declining bone mechanoresponse. To this end, we have developed a 3D bone marrow analog which controls trabecular geometry, marrow mechanics and external stimuli.

Finite element (FE) models of hydrogels, representing bone marrow, were generated using instantaneous compression (1000% strain/s, 20% strain) and relaxation experiments (100s) of both gelatin and hyaluronin-based hydrogels. …


Characterizing Students’ Engineering Design Strategies Using Energy3d, Jasmine Singh, Viranga Perera, Alejandra Magana, Brittany Newell Apr 2021

Characterizing Students’ Engineering Design Strategies Using Energy3d, Jasmine Singh, Viranga Perera, Alejandra Magana, Brittany Newell

Discovery Undergraduate Interdisciplinary Research Internship

The goals of this study are to characterize design actions that students performed when solving a design challenge, and to create a machine learning model to help future students make better engineering design choices. We analyze data from an introductory engineering course where students used Energy3D, an open source computer-aided design software, to design a zero-energy home (i.e. a home that consumes no net energy over a period of a year). Student design actions within the software were recorded into text files. Using a sample of over 300 students, we first identify patterns in the data to assess how students …


Modeling Considerations For Built-Up Compression Members In Communication Towers, Ghada M. El-Mahdy P.Eng., Ceng, Amro A. Alawamry Apr 2021

Modeling Considerations For Built-Up Compression Members In Communication Towers, Ghada M. El-Mahdy P.Eng., Ceng, Amro A. Alawamry

Civil Engineering

It is a well-established fact that built-up compression members exhibit extra flexibility than their equivalent solid members due to the shear action which effects the overall stability. This is usually taken into consideration by using a modified slenderness ratio for buckling modes that involve relative deformation of the interconnectors. Built-up members are often used as space truss members in communication towers. When modeling communication towers in structural analysis programs like SAP2000, the built-up member is usually defined as a single member element with a double section cross section. This does not catch the increase in deflection in the member due …


Vascular Endothelial Dysfunction And Effects On Arterial Wall Microstructure, Jeffrey Thomas Rodgers Apr 2021

Vascular Endothelial Dysfunction And Effects On Arterial Wall Microstructure, Jeffrey Thomas Rodgers

Theses and Dissertations

Vascular endothelial cell dysfunction (ECD) is a disease characterized by the inability of the vascular endothelial cells to transmit signaling molecules, namely nitric oxide (NO), in response to changes in blood flow rate. This disease is shown to be incident in the onset of more severe vascular disease such as hypertension, atherosclerosis, and heart failure. Long-term ECD is shown to cause long-term remodeling such as decreased flow-mediated dilation, increased pulse-wave velocity, intimal-medial thickening, and increased wall stiffness due to collagen deposition. We used second harmonic generation (SHG) microscopy to analyze this change in the collagen microstructure of the arterial extracellular …


Coal Pyrolysis Models For Use In Massively Parallel Oxyfuel-Fired Boiler Simulations, Andrew Perry Richards Mar 2021

Coal Pyrolysis Models For Use In Massively Parallel Oxyfuel-Fired Boiler Simulations, Andrew Perry Richards

Theses and Dissertations

Accurately modeling key aspects of coal combustion allows for the virtual testing and application of new technologies and processes without the need for investments in lab- and pilot-scale facilities, since such facilities may only be used for a few small tests. However, modeling of subprocesses must not only be accurate but computationally efficient. Modeling of coal devolatilization reactions and processes are one of the important parts of large-scale simulations of coal combustion systems. The work presented here details efforts to improve the modeling of coal devolatilization processes in massively-parallel simulations of coal combustors, including: (1) devolatilization rate/yield models, (2) modeling …


Integrated Approach For Diversion Route Performance Management During Incidents, Rajib Chandra Saha Mar 2021

Integrated Approach For Diversion Route Performance Management During Incidents, Rajib Chandra Saha

FIU Electronic Theses and Dissertations

Non-recurrent congestion is one of the critical sources of congestion on the highway. In particular, traffic incidents create congestion in unexpected times and places that travelers do not prepare for. During incidents on freeways, route diversion has been proven to be a useful tactic to mitigate non-recurrent congestion. However, the capacity constraints created by the signals on the alternative routes put limits on the diversion process since the typical time-of-day signal control cannot handle the sudden increase in the traffic on the arterials due to diversion. Thus, there is a need for proactive strategies for the management of the diversion …


Strength, Fracture Evolution, And Permeability Changes From Confined Brazilian Tests On Sandstone, Tyler Louis Hagengruber Jan 2021

Strength, Fracture Evolution, And Permeability Changes From Confined Brazilian Tests On Sandstone, Tyler Louis Hagengruber

Civil Engineering ETDs

This research reports on confined Brazilian strength tests and concurrent permeability testing on sandstone. The majority of the tests measured permeability during loading to failure in the confined extension region. Additional testing includes unloading and reloading cycles to detect the development of microcracks and the dependence of permeability on mixed stress conditions. Further testing characterizes fracture networks by observing porosity changes due to microcrack interactions before peak load. All tests involve 5 cm diameter disk-shaped, jacketed samples that are subjected to confining stresses while they are diametrically loaded. Specially designed end caps allow for gas flow measurements. The test configuration …


Development Of A Hurricane Recovery Function And Resilience Model For Single-Family Residential Homes, Uriel Robert Donald Clark Jan 2021

Development Of A Hurricane Recovery Function And Resilience Model For Single-Family Residential Homes, Uriel Robert Donald Clark

Theses and Dissertations

The resilience of communities, infrastructure, and the environment in the face of hurricanes has increasingly become of public interest in the wake of recent natural disasters and environmental activism. Previous methodologies have attempted to quantify resilience for various structures and scenarios. Many studies have primarily investigated the robustness of critical infrastructure (e.g., bridges, emergency facilities, and water systems) which are essential to the function of a community. However, few studies have applied this approach to individual residential buildings. Therefore, this research aimed to adapt the most recent recovery functions developed for residential homes by considering measurable factors that are known …


Architecture Design Of An Emergency Command Simulation Exercise Platform Based On Tena, Peng Zhang, Qinfu Li Jan 2021

Architecture Design Of An Emergency Command Simulation Exercise Platform Based On Tena, Peng Zhang, Qinfu Li

Journal of System Simulation

Abstract: Based on the analysis of the current situation and development needs of the emergency command simulation exercise platform and the common characteristics of most emergency command case scenarios, an emergency command simulation exercise platform architecture based on TENA (Test and Training Enabling Architecture) is designed and put forward, which can expand various simulation models such as disaster accidents, disaster-bearing subjects, higher-lower linkage command organizations, rescue forces, natural environment, etc. in a multi-granularity and modular manner, and interface with various exercise support and analysis evaluation tools, as well as heterogeneous systems such as external three-dimensional simulation, virtual reality/augmented reality equipment …


Modeling Emergence Of Network Radar Countermeasure System, Huang Chen, Jianqing Qi, Fangzheng Liu Jan 2021

Modeling Emergence Of Network Radar Countermeasure System, Huang Chen, Jianqing Qi, Fangzheng Liu

Journal of System Simulation

Abstract: Network radar countermeasure system (NRCS) is a new kind of integrated electronic warfare system with the integrated network developing trend of radar and EW equipment, and emergence is the typical complex feature of NRCS. The connotation and composition of the NRCS emergence was interpreted. Four sources of the NRCS emergence were analyzed: composition effect, structural effect, interaction effect and environmental effect. The conceptual models and mathematical models of the NRCS emergence were built from three aspects: system reconnaissance detection emergence, system target identification emergence and system jamming emergence. Simulation results coincide with the NRCS emergence source analysis, which verifies …


Modeling And Simulation Of Traction System In Hybrid Shunting Locomotive, Kun Shen, Wang Ling, Wang Jian, Xiaoyang Yao Jan 2021

Modeling And Simulation Of Traction System In Hybrid Shunting Locomotive, Kun Shen, Wang Ling, Wang Jian, Xiaoyang Yao

Journal of System Simulation

Abstract: The structure of traction system in hybrid shunting locomotive was analyzed, and the working principles of traction system under multiform power models were introduced. Based on which, the models of traction system and power accumulators of this hybrid shunting locomotive were built by MATLAB/Simulink, then the simulation experiments on hybrid shunting locomotive with the power models of hybrid power, and pure diesel generator power or pure accumulator power were done respectively. The simulation results show that hybrid shunting locomotive can achieve reliable operation in diflFerent conditions by the designed main circuit structure, parameters and system energy management strategy.


Relating Spontaneous Activity And Cognitive States Via Neurodynamic Modeling, Matthew Singh Jan 2021

Relating Spontaneous Activity And Cognitive States Via Neurodynamic Modeling, Matthew Singh

Arts & Sciences Electronic Theses and Dissertations

Stimulus-free brain dynamics form the basis of current knowledge concerning functional integration and segregation within the human brain. These relationships are typically described in terms of resting-state brain networks—regions which spontaneously coactivate. However, despite the interest in the anatomical mechanisms and biobehavioral correlates of stimulus-free brain dynamics, little is known regarding the relation between spontaneous brain dynamics and task-evoked activity. In particular, no computational framework has been previously proposed to unite spontaneous and task dynamics under a single, data-driven model. Model development in this domain will provide new insight regarding the mechanisms by which exogeneous stimuli and intrinsic neural circuitry …


Management Of The Phosphorus-Cladophora Dynamic At A Site On Lake Ontario Using A Multi-Module Bioavailable P Model, Martin Auer, Cory P. Mcdonald, Anika Kuczynski, Chenfu Huang Jan 2021

Management Of The Phosphorus-Cladophora Dynamic At A Site On Lake Ontario Using A Multi-Module Bioavailable P Model, Martin Auer, Cory P. Mcdonald, Anika Kuczynski, Chenfu Huang

Michigan Tech Publications

The filamentous green alga Cladophora grows to nuisance proportions in Lake Ontario. Stimulated by high phosphorus concentrations, nuisance growth results in the degradation of beaches and clogging of industrial water intakes with attendant loss of beneficial uses. We develop a multi-module bioavailable phosphorus model to examine the efficacy of phosphorus management strategies in mitigating nuisance algal growth. The model platform includes modules simulating hydrodynamics (FVCOM), phosphorus-phytoplankton dynamics (GEM) and Cladophora growth (GLCMv3). The model is applied along a 25 km stretch of the Lake Ontario nearshore, extending east from Toronto, ON and receiving effluent from three wastewater treatment plants. Simulation …


Sae Formula Team Carbon Fiber Seat, Jacob Jaksic Jan 2021

Sae Formula Team Carbon Fiber Seat, Jacob Jaksic

Williams Honors College, Honors Research Projects

roject is for the Formula SAE Zips Racing team here at the University of Akron. The team includes Jacob Jaksic, Sean Turner, Dovydas Sodys, Mike White, and Sevin Johnson. We are tasked with reducing the weight of their current seat, while remaining comfortable to the driver. Our plan was to do this with a lightweight material, specifically carbon fiber. Many different steps were required when outlining this project: finalizing a design with verification from our Zips racing advisor, completing FEA analysis on finished design, acquiring material to be molded into seat, and finding a company to fabricate out of carbon …


Creating A Driving Workload Model And Identifying Best Practices, Josalin Kumm, Holly Handley, Yusuke Yamani Jan 2021

Creating A Driving Workload Model And Identifying Best Practices, Josalin Kumm, Holly Handley, Yusuke Yamani

Psychology: Interdisciplinary Research in Behavioral Sciences of Transportation Issues

One major way to investigate distracted driving is to have drivers engage in a secondary task. Driving models are one way to better understand workload during driving which could result in safer driving. During this study, we create a driving model using cognitive task analysis software to analyze workload with N-Back tasks. N-Back task requires the driver to memorize and repeat numbers and letters. The result will help us determine if we can continue using this software in future research and analysis workload in a scenario with secondary tasks by comparing it to other analysis software in the framework of …


Quantifying The Impacts Of Land Use, Management And Climate Change On Water Resources In Missouri River Basin, Arun Bawa Jan 2021

Quantifying The Impacts Of Land Use, Management And Climate Change On Water Resources In Missouri River Basin, Arun Bawa

Electronic Theses and Dissertations

A location-specific evaluation of hydrological landscape responses concerning past and projected climate and land use land cover (LULC) changes can provide a powerful intellectual basis for developing efficient and profitable agroecosystems, and overcoming uncertain and detrimental consequences of LULC and climate shifts. This dissertation assessed the impacts of land use, management, and climate change on water resources in the Missouri River Basin (MRB) through four specific studies that included: (i) to study the responses of leached nutrient concentrations and soil health to winter rye cover crop (CC) under no-till corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation, (ii) to …


Effect Of Ultra-High Pulse Frequency On The Resolution In The Electrochemical Deposition Of Nickel, Abishek Balsamy Kamaraj, Natalie Reed, Murali Sundaram Jan 2021

Effect Of Ultra-High Pulse Frequency On The Resolution In The Electrochemical Deposition Of Nickel, Abishek Balsamy Kamaraj, Natalie Reed, Murali Sundaram

Industrial & Manufacturing Engineering Presentations And Conference Materials

Using localized electrochemical deposition (LECD) as a mask-less direct writing methodology, metal shapes are printed. The electrochemical double-layer capacitance at ultra-high frequencies is hypothesized to cause a localized deposition and the effect of pulse frequency on the current density is modeled to predict the deposition resolution and rate of deposition. Experimental results confirm that the deposition resolution and efficiency of the LECD process increase with the increase of pulse frequency. Deposition resolution 80% smaller than the tool diameter is feasible in the LECD of nickel used with a ø 250 μm tool at 1 MHz pulsed power.


Understanding The Weather- And Soil-Related Variability In Agricultural Water Footprints: Case Study Of Maize And Soybeans Grown In The St. Joseph Watershed, Karleigh M. Krieg Jan 2021

Understanding The Weather- And Soil-Related Variability In Agricultural Water Footprints: Case Study Of Maize And Soybeans Grown In The St. Joseph Watershed, Karleigh M. Krieg

Dissertations, Master's Theses and Master's Reports

Introduced in 2002, the water footprint is a valuable tool for understanding the consumption of freshwater resources. The traditional approach to quantifying the water footprint is to sum the green, blue, and gray water footprint components. The green water footprint is the volume of water that comes from precipitation, is stored in the soil, and used by vegetation. The blue water footprint is the volume of surface or ground water that is withdrawn and applied to cultivated lands via irrigation. These components are based on the evapotranspiration of green and blue water resources, respectively. The gray water footprint is the …


Sae Formula Team Carbon Fiber Seat, Sean Turner, Jacob Jaksic Jan 2021

Sae Formula Team Carbon Fiber Seat, Sean Turner, Jacob Jaksic

Williams Honors College, Honors Research Projects

This project is for the Formula SAE Zips Racing team here at the University of Akron. The team includes Jacob Jaksic, Sean Turner, Dovydas Sodys, Mike White, and Sevin Johnson. We are tasked with reducing the weight of their current seat, while remaining comfortable to the driver. Our plan was to do this with a lightweight material, specifically carbon fiber. Many different steps were required when outlining this project: finalizing a design with verification from our Zips racing advisor, completing FEA analysis on finished design, acquiring material to be molded into seat, and finding a company to fabricate out of …


Workspace And Kinematic Modeling And Analysis Of Semi-Robotic Laparoscopic Surgery, Immanuel E. Girgis Jan 2021

Workspace And Kinematic Modeling And Analysis Of Semi-Robotic Laparoscopic Surgery, Immanuel E. Girgis

Honors Undergraduate Theses

Laparoscopic Surgery has been revolutionized by the world of Surgical Robotics. Robot-Assisted Surgeries have been proven to have many advantages over the fundamental, traditional "by-hand" procedures previously conducted, and still currently being done for certain operations. Robot-assisted surgery may offer benefits to patients through the use of minimally invasive techniques, which may result in reduced blood loss, reduced blood transfusion, fewer complications, reduced postoperative pain, shorter hospital stays, and reduced recovery times (Ho et al., 2011). Studies have proven that robotic surgery may lead to patients recovering faster depending on the timeframe and the type of procedure (Tang et al., …


Role Of Eta Phase Evolution On Creep Properties Of Nickel Base Superalloys Used In Advanced Electric Power Generation Plants, Ninad Mohale Jan 2021

Role Of Eta Phase Evolution On Creep Properties Of Nickel Base Superalloys Used In Advanced Electric Power Generation Plants, Ninad Mohale

Dissertations, Master's Theses and Master's Reports

Advanced fossil energy power generation plants require materials that withstand high temperatures and corrosive environments. One such material that is used in steam turbines is Nimonic 263. It is a nickel-base superalloy that is principally strengthened by gamma primephase (Ni3(Ti, Al)) and has an L12structure. At extended times and at turbine operating temperatures however, eta (Ni3Ti) phase is known to form at the expense of gamma prime. Eta has a complex DO24structure and is the stable phase between 750°C and 900°C, but with slow kinetics of formation. Little is understood about eta …


Improving Real-Time Methane Monitoring In Longwall Coal Mines Through System Response Characterization Of A Multi-Nodal Methane Detection Network, Brian Philip Cappellini Jan 2021

Improving Real-Time Methane Monitoring In Longwall Coal Mines Through System Response Characterization Of A Multi-Nodal Methane Detection Network, Brian Philip Cappellini

Graduate Theses, Dissertations, and Problem Reports

Machine automation and atmospheric monitoring are used by many industries to improve safety and productivity in the workplace. The underground Methane Watchdog System (MWS) is a multi-nodal network of sensors currently under development. The MWS aims to improve safety and productivity by introducing 10 compact sampling units designed to be easily integrated within the current roof support equipment of the mine. Each unit contains an array of sensors used to continuously monitor the environmental conditions which include methane concentration, temperature, pressure, and relative humidity. All MWS units report information back to a remote central processing hub (CPH) which collects nodal …


Theoretical Analysis Of Experimental Data Of Sodium Diffusion In Oxidized Molybdenum Thin Films, Orlando Ayala, Benjamin Belfore, Tasnuva Ashrafee, John Akwari, Grace Rajan, Shankar Karki, Deewakar Poudel, Sylvain Marsillac Jan 2021

Theoretical Analysis Of Experimental Data Of Sodium Diffusion In Oxidized Molybdenum Thin Films, Orlando Ayala, Benjamin Belfore, Tasnuva Ashrafee, John Akwari, Grace Rajan, Shankar Karki, Deewakar Poudel, Sylvain Marsillac

Engineering Technology Faculty Publications

In this work, the diffusion process of sodium (Na) in molybdenum (Mo) thin films while it was deposited on soda lime glass (SLG) was studied. A small amount of oxygen was present in the chamber while the direct-current (DC) magnetron sputtering was used for the deposition. The substrate temperatures were varied to observe its effect. Such molybdenum films, with or without oxidations, are often used in thin film solar cells, either as back contact or as hole transport layers. Secondary ion mass spectrometry (SIMS) was used to quantify the concentration of the species. A grain diffusion mechanistic model incorporating the …