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Articles 2581 - 2610 of 6329

Full-Text Articles in Engineering

Combustion Wave Propagation Enhancement Of A Nitrocellulose Solid Monopropellant, Omar R. Yehia, Shourya Jain, Li Qiao Aug 2015

Combustion Wave Propagation Enhancement Of A Nitrocellulose Solid Monopropellant, Omar R. Yehia, Shourya Jain, Li Qiao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Improvement and control of the burning behavior and characteristics of solid fuels promise improved performance of systems ranging from solid rocket motors to microelectromechanical systems. Introducing methods to enhance combustion wave propagation velocities of solid propellants is a crucial step in realizing improved performance in rocket motors that use organic nitrate-based propellants. This work aims to enhance the burning characteristics of solid fuels through the use of thermally guided combustion waves. In order to increase the burning rate of solid nitrocellulose fuel layers, graphite sheets were used as thermally conductive bases in order to substantially improve heat transfer to unburned …

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Cell-Matrix Interactions During En Masse Cell Migration, Meng Zhuang, Altug Ozcelikkale, Bumsoo Han Aug 2015

Cell-Matrix Interactions During En Masse Cell Migration, Meng Zhuang, Altug Ozcelikkale, Bumsoo Han

The Summer Undergraduate Research Fellowship (SURF) Symposium

Extended wound care, including prolonged treatment of burn injuries, acute and chronic wounds, is a significant source of patient discomfort and financial burden to public healthcare programs. Both accelerated healing and prevention of scar formation are highly desired but remain to be challenging to achieve. This is primary due to limited understanding of interactions between cells and the surrounding extracellular matrix (ECM) during wound healing. Particularly, collective migration of fibroblasts through provisional matrix, so called en masse migration, is one of these interactions that play a critical role in later stages of granulation tissue formation and wound closure. In addition …

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Dsmc Simulation Of Microstructure Actuation By Knudsen Thermal Force, Aaron Pikus, Israel Sebastiao, Andrew Strongrich, Alina Alexeenko Aug 2015

Dsmc Simulation Of Microstructure Actuation By Knudsen Thermal Force, Aaron Pikus, Israel Sebastiao, Andrew Strongrich, Alina Alexeenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

In many industrial and research applications there is a need for vacuum sensors with higher accuracy and spatial resolution than what is currently available. Examples of target applications include high-altitude platforms, satellites and in-vacuum manufacturing processes such as freeze-drying of food and pharmaceuticals. In this connection, a novel pressure sensor, named Microelectromechanical In-plane Knudsen Radiometric Actuator (MIKRA), has been developed by at Purdue University. MIKRA is based on Knudsen thermal forces generated by rarefied flow driven by thermal gradients within the microstructure Thus, the goal of this work is to model the rarefied gas flow in the MIKRA sensor under …

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Implantable Device For Wireless Regulation Of The Bladder Through Pelvic Nerve Stimulation, Kelsey C. Bayer, Chris Quinkert, Pedro Irazoqui Aug 2015

Implantable Device For Wireless Regulation Of The Bladder Through Pelvic Nerve Stimulation, Kelsey C. Bayer, Chris Quinkert, Pedro Irazoqui

The Summer Undergraduate Research Fellowship (SURF) Symposium

Urinary incontinence (UI) is the involuntarily urination that usually effects older people or is the result of an injury. UI affects more than eleven million people and the cost of incontinence management in the United States in 2000 was $19.5 billion. Where conventional physical therapies have failed, pelvic nerve stimulation is a promising form of regulating the bladder long term. Piezoresistive pressure sensors consist of two variable resistance values and two known resistance values that are represented on a daughterboard. This unknown resistance represents the change in pressure. The filling and voiding of the bladder was characterized through acute surgeries. …

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Graphene Field Effect Transistor For Radiation Detection On A Micron To Millimeter Scale, Peter C. Lamm, Robert Speer Bean, Zachary Shollar Aug 2015

Graphene Field Effect Transistor For Radiation Detection On A Micron To Millimeter Scale, Peter C. Lamm, Robert Speer Bean, Zachary Shollar

The Summer Undergraduate Research Fellowship (SURF) Symposium

Novel technology in radiation detection is critical to advancing radiation detectors for their many applications. Graphene has shown to be able to change its conductivity in the presence of an electric field; this makes it an excellent candidate to be used as a radiation detector for the detection of the charges generated during radiation interactions. Research has been done on making micron scale graphene field effect transistors (GFET) with graphene on a Si/SiO2 wafer, but it is critical that we try to increase the scale. Unknowns persist in scaling graphene to millimeter sizes. This study plans to elucidate any …

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Detecting Periods Of Flight With High Task Load, James R. Parkinson, Steven J. Landry, Quang Dao, Caitlin Surakitbanharn Aug 2015

Detecting Periods Of Flight With High Task Load, James R. Parkinson, Steven J. Landry, Quang Dao, Caitlin Surakitbanharn

The Summer Undergraduate Research Fellowship (SURF) Symposium

Tools that predict dangerous working conditions empirically in the cockpit could greatly improve aviation safety. In an effort to lay the groundwork for such tools, this study will investigate whether a link exists between task load and pilots’ control strategies, their biometric data, and their planes’ position data. Using X Plane simulation software, an experiment will be run in which licensed pilots will fly a 3-nautical-mile approach into Mineta San Jose International Airport 4 times, under different task load conditions. During the flight, participants’ pupil diameters will be recorded along with the simulated aircraft position data and cognitive control modes. …

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Interactive Computer Aided Design Of Electrochemical Systems, Lucas D. Robinson Mr., R. Edwin García Dr., Aniruddha Jana Mr. Aug 2015

Interactive Computer Aided Design Of Electrochemical Systems, Lucas D. Robinson Mr., R. Edwin García Dr., Aniruddha Jana Mr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

The most popular and widely used rechargeable battery numerical model, the dualfoil, was developed in fortran by John Newman and coworkers1-3, and enables the user to describe the time-dependent electrochemical transport of lithium and charge, through the application of concentrated solution theory in porous media. Such a model has enabled the design of many advanced lithium-ion batteries for hybrid and plug-in electric vehicles that can operate under high current densities. Historically, however, the dualfoil and other subsequently derived models are cumbersome and unwieldy when used, and offer limited flexibility regarding parameter variability, integration into more sophisticated numerical descriptions, coupling to …

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Quantum Modeling Of Thermodynamic Properties Of Warm Dense Aluminum, Nicholas Termini, Gennady Miloshesky, Ahmed Hassanein Aug 2015

Quantum Modeling Of Thermodynamic Properties Of Warm Dense Aluminum, Nicholas Termini, Gennady Miloshesky, Ahmed Hassanein

The Summer Undergraduate Research Fellowship (SURF) Symposium

Warm dense matter is attracting a lot of attention in the scientific community, due to its formation during intense laser-matter interaction and inertial confinement fusion. However, there is no accurate solution to mapping out the thermodynamic properties of warm dense matter. Experimental data are also incredibly scarce making computational models an incredibly useful tool. This paper provides equation of state (EOS) data for aluminum at specific densities within the warm dense matter regime. The EOS data were calculated using quantum molecular dynamics, which was performed by the computational package QuatumEspresso. EOS were determined by collecting and recording pressure after achieving …

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A Non-Invasive Method Of Measuring Respiration While Providing Wireless Power For Rodents With Implantable Devices, Jynx O. Boyne, Daniel J. Pederson, Zhi Wang, Pedro Irazoqui Dr. Aug 2015

A Non-Invasive Method Of Measuring Respiration While Providing Wireless Power For Rodents With Implantable Devices, Jynx O. Boyne, Daniel J. Pederson, Zhi Wang, Pedro Irazoqui Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Respiratory measurements can be used as diagnostic and research tools. Spirometry is the gold standard for gaining these measurements, but is difficult to use in rodents as it requires an invasive procedure. Total Body Plethysmograpy (TBP) is a non-invasive way to measure respiration rates that does not cause stress to the rodent. In this system, the subject is encased in a solid, constant volume chamber with measurements determining the subject’s respiration. When using TBP in medical or research settings, challenges occur in powering devices within the TBP chamber as wires and other recording equipment compromise the airtightness of the chamber. …

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Recovery Of Nutrients From Animal And Human Wastes, Nathaniel E. Kallmyer, Zhe Sun, Kaitlin Harris, Zhi Zhou, Ernest R. Blatchley Iii Aug 2015

Recovery Of Nutrients From Animal And Human Wastes, Nathaniel E. Kallmyer, Zhe Sun, Kaitlin Harris, Zhi Zhou, Ernest R. Blatchley Iii

The Summer Undergraduate Research Fellowship (SURF) Symposium

Removal of nitrogen- and phosphorus-containing molecules from wastewater is necessary to prevent excessive growth of algae and resulting chemical changes to bodies of water. Of wastewater components, urine contains relatively high concentrations of nitrogen and phosphorus, the majority of which is ultimately present as ammonia and phosphate. Separation and stabilization of these nutrients may also allow for their reuse as fertilizer. Before the nutrients may be stored, they must be stabilized. At least a portion of ammonia-N must be converted to nonvolatile nitrogen. This may be achieved by using ammonia- and nitrite-oxidizing bacteria (AOB and NOB, respectively) to convert ammonia …

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Visualization And Analysis Of Sensory Data, Luke Neumann, Sung Yeon Choi, Brian Olsen, Sungahn Ko, David Ebert Dr. Aug 2015

Visualization And Analysis Of Sensory Data, Luke Neumann, Sung Yeon Choi, Brian Olsen, Sungahn Ko, David Ebert Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Recently, California has suffered a severe drought, making water a scarce resource to its population. Many viticulturists are based in this area who rely on heavy irrigation to produce a better grape and a better wine. Not just in California, but throughout the nation, irrigation must be applied intelligently for efficient use of water and funding. By taking measurements of physical characteristics of a vineyard over time, one may be able to visualize trends in the data which lend itself to describing preferred growing methods. Wireless sensors can be used to take measurements including moisture, temperature, sunlight, and more. Sensors …

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A Novel Synthetic Yeast For Enzymatic Biodigester Pretreatment, Tianyu Tan, Mark S. Aronson, Arren Liu, Jill H. Osterhus, Melissa Robins, Suraj Mohan, Erich Leazer, Bowman Clark, Alexa Petrucciani, Katherine Lowery, James Welch, Casey Martin, Helena Lysandrou, Michael E. Scharf, Jenna Rickus Aug 2015

A Novel Synthetic Yeast For Enzymatic Biodigester Pretreatment, Tianyu Tan, Mark S. Aronson, Arren Liu, Jill H. Osterhus, Melissa Robins, Suraj Mohan, Erich Leazer, Bowman Clark, Alexa Petrucciani, Katherine Lowery, James Welch, Casey Martin, Helena Lysandrou, Michael E. Scharf, Jenna Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Lignin, a complex organic polymer, is a major roadblock to the efficiency of biofuel conversion as it both physically blocks carbohydrate substrates and poisons biomass degrading enzymes, even if broken down to monomer units. A pretreatment process is often applied to separate the lignin from biomass prior to biofuel conversion. However, contemporary methods of pretreatment require large amounts of energy, which may be economically uncompelling or unfeasible. Taking inspiration from several genes that have been isolated from termites and fungi which translate to enzymes that degrade lignin, we want to establish a novel “enzymatic pretreatment” system where microbes secrete these …

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High Pressure Combustion And Supersonic Jet Ignition For H2/Air, Michael G. Woodworth, Sayan Biswas, Li Qiao Aug 2015

High Pressure Combustion And Supersonic Jet Ignition For H2/Air, Michael G. Woodworth, Sayan Biswas, Li Qiao

The Summer Undergraduate Research Fellowship (SURF) Symposium

There are many incentives to increase the fuel efficiency of combustion processes. This paper looks at two available options to achieve this goal. The former aims to develop an experimental method that can analyze combustion at extremely high pressures to improve the understanding of high pressure H2/air combustion. Experimental data has been lacking a suitable combustion diagnostic to visualize high pressure combustion processes, making it difficult to improve the process. Improvement of x-ray diffraction tomography in a windowless combustor makes it possible to see flame propagation at high pressure. The procedure and chamber are still in the design phase, yet …

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Integrating Systems For Liquid/Substrate Characterization And Functional Printing, Jianyi Du, J. William Boley, Rebecca K. Kramer Aug 2015

Integrating Systems For Liquid/Substrate Characterization And Functional Printing, Jianyi Du, J. William Boley, Rebecca K. Kramer

The Summer Undergraduate Research Fellowship (SURF) Symposium

Gallium-Indium alloys are recently applied in fabricating soft devices, such as stretchable sensors, electric circuits, micro pumps and optics. Its printability demonstrates the possibility for a wide extension of the application. Current fabrication methods are inefficient when printing is most handled manually, and are highly dependent on material properties. There is need for a fast way to characterize material properties, and to functionally print the given shape on the substrate. This paper presents the construction of an efficiently integrated system with optical imaging and functional printing for Gallium-Indium alloys. The imaging section allows for characterization of material properties to fast …

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Simulation Design For Photovoltaics Using Finite Difference Time Domain And Quadratic Complex Rational Function Methods, Jacob R. Duritsch, Haejun Chung, Peter Bermel Aug 2015

Simulation Design For Photovoltaics Using Finite Difference Time Domain And Quadratic Complex Rational Function Methods, Jacob R. Duritsch, Haejun Chung, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

Photovoltaics (PV) can in principle supply enough renewable energy to offset a great deal of fossil fuel usage. To achieve this transition, it is critical to develop improved PV cells with decreased material costs and improved efficiencies. This goal can be greatly facilitated by a tool simulating the absorption and efficiency of experimentally relevant 3-D PV designs made of realistic materials, including those that have not yet been discovered. By incorporating the quadratic complex rational function algorithm (QCRF) with the finite difference time domain methods (FDTD), simulations can include frequency response and optical properties, while allowing full customization of tandem …

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Hot Surface Ignition, Yerbatyr Tursyn, Vikrant Goyal, Alicia Benhidjeb-Carayon, Richard Simmons, Scott Meyer, Jay P. Gore Aug 2015

Hot Surface Ignition, Yerbatyr Tursyn, Vikrant Goyal, Alicia Benhidjeb-Carayon, Richard Simmons, Scott Meyer, Jay P. Gore

The Summer Undergraduate Research Fellowship (SURF) Symposium

Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas turbine fuels Jet-A, JP-8, and JP-5 were measured. A test apparatus capable of providing reproducible data was designed and fabricated to experimentally investigate the hot surface ignition …

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Development Of A Parallel Multiphase Lattice-Boltzmann Solver To Study Stokes Number Effects On Particle Trajectories, Lenan Zhang, Anand Samuel Jebakumar, John Abraham Aug 2015

Development Of A Parallel Multiphase Lattice-Boltzmann Solver To Study Stokes Number Effects On Particle Trajectories, Lenan Zhang, Anand Samuel Jebakumar, John Abraham

The Summer Undergraduate Research Fellowship (SURF) Symposium

Particle-laden flows are important owing to their relevance to many engineering devices such as coal combustors, gasifiers and solar thermochemical reactors. In a recent experimental study by Lau and Nathan [1], it was found that particles in a turbulent pipe flow tend to migrate preferentially depending on their Stokes number (St). Particles with a high St (>10) are concentrated near the axis while those with low St (

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Quantification Of Analyte Concentration From A Paper-Based Lateral Flow Assay Device Using Reflective Sensors, Megan Z. Chiu, Jacqueline Linnes Aug 2015

Quantification Of Analyte Concentration From A Paper-Based Lateral Flow Assay Device Using Reflective Sensors, Megan Z. Chiu, Jacqueline Linnes

The Summer Undergraduate Research Fellowship (SURF) Symposium

Paper-based point-of-care (POC) diagnostics is a growing field in global health due to the extreme portability, accuracy, affordability, and ease of use of these tests. Advancements in recent years have led to more accurate detection and improved functionality using multistep molecular diagnostics. Many such assays utilize lateral flow detection strips for visualization of diagnostic results by eye, which limits the results to qualitative Yes/No readouts. This project focused on combining recent developments in paper-based POC diagnostics to develop and optimize an in-house built quantitative paper-based diagnostic reader for lateral flow detection in low-resource settings. Initially different sensors, including photocell sensors, …

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Identifying Mode Confusion In Recorded Aircraft Data, James Douglas Thomas, Yul Kwon, Steven J. Landry Aug 2015

Identifying Mode Confusion In Recorded Aircraft Data, James Douglas Thomas, Yul Kwon, Steven J. Landry

The Summer Undergraduate Research Fellowship (SURF) Symposium

In recent decades, commercial aviation accidents have occurred due to human-machine interaction (HMI) problems known as “mode confusion.” This is caused, in some cases, by a lack of understanding of onboard systems by pilots. Large amounts of Flight Operational Quality Assurance (FOQA) data are available, analysis of which could assist in identification of safety risks in daily operations. Through analysis of pilot reactions and recorded aircraft data, methods to detect mode confusion are developed to improve aviation safety. This study was conducted by inducing mode confusion into a flight simulation scenario and analyzing aircraft data to detect emerging patterns. Three …

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Analysis Of The Fabrication Conditions In Organic Field-Effect Transistors, Rachel M. Rahn, Yan Zhao, Jianguo Mei Aug 2015

Analysis Of The Fabrication Conditions In Organic Field-Effect Transistors, Rachel M. Rahn, Yan Zhao, Jianguo Mei

The Summer Undergraduate Research Fellowship (SURF) Symposium

Polymer-based organic field-effect transistors have raised substantial awareness because they enable low-cost, solution processing techniques, and have the potential to be implemented in flexible, disposable organic electronic devices. The performance of these devices is highly dependent on the processing conditions, as well as the intrinsic properties of the polymer. Processing conditions play an important role in semiconductor film formation and device performance. These factors may provide an important link between structure and performance. In this study, an empirical analysis tool, Process Scout, was applied to assess processing factors such as polymer concentration and silicon modification. This sanctioned the creation of …

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Simulating Nanowires And Ultra-Thin Body Transistors Using Nemo5 On Nanohub.Org, Liang Yuan Dai, James E. Fonseca, Chu Yuan Chen, Gerhard Klimeck Aug 2015

Simulating Nanowires And Ultra-Thin Body Transistors Using Nemo5 On Nanohub.Org, Liang Yuan Dai, James E. Fonseca, Chu Yuan Chen, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

During the past twenty years, the most important aspects of semiconductor electronics have advanced into the nanometer range, resulting in exponential increases of microprocessor computing performance. As the size of electrical components continues to shrink, the cost of experimental research and industrial fabrication in this field has increased dramatically. Thus, the development of accurate nanoscale model simulations becomes necessary as a measure to decrease the high financial expenses of advancing semiconductor technology. This simulator supports atomistic modeling in order to provide an accurate description of the nanoscale devices, as current electrical components operate in the quantum regime and are affected …

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Kinetic Modeling Of Roll To Roll Rfcvd Plasma, Kudzo S. Ahegbebu, Siva Sashank Tholeti, Alina A. Alexeenko Aug 2015

Kinetic Modeling Of Roll To Roll Rfcvd Plasma, Kudzo S. Ahegbebu, Siva Sashank Tholeti, Alina A. Alexeenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

Roll-to-roll radio frequency plasma enhanced chemical vapor deposition (R2R RFCVD) is a technique for large-scale synthesis of high quality graphitic nanopetals. Graphitic nanopetals are petal-like graphene structures with remarkable electrical and mechanical properties with major industrial applications such as microsupercapacitors. RFCVD uses a non-equilibrium plasma with high energy electrons to catalyze chemical reactions, induce the creation of free radicals, and promote otherwise high temperature chemistry in a low temperature environment. Understanding how bulk plasma characteristics (particularly, power and number densities) vary with changing reactor parameters is an important step towards optimizing synthesis techniques. In our present work we use the …

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Towards In Situ Measurements Of Platinum Dissolution Using Metallothionein-Based Biosensor, Stephanie Cernera, Hyowon Lee Aug 2015

Towards In Situ Measurements Of Platinum Dissolution Using Metallothionein-Based Biosensor, Stephanie Cernera, Hyowon Lee

The Summer Undergraduate Research Fellowship (SURF) Symposium

Platinum-based (Pt) electrodes are used ubiquitously in neurostimulation for their high charge capacity and safety. However, Pt electrodes are known to dissolve during stimulation in the presence of chloride (Cl) to form Pt-Cl byproducts. These byproducts may have deleterious effects on surrounding tissue by preventing cell division and causing apoptosis. Several studies have quantified the amount of neurostimulation-induced Pt dissolution in vivo using various analytical methods; however, these approaches require disruptive sampling of tissue. Periodic measurements from a stimulating electrode using an in situ sensor may provide additional insights into Pt dissolution process. To create the sensor for detecting Pt …

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Optimal Surfactant Selection For Chemical Enhanced Oil Recovery In Low Temperature, Low Salinity, High Hardness Reservoirs, Christian D. White, Ryan A. Mulvenna, Rituraj Borgohain, Cliff Johnston, Bryan Boudouris Aug 2015

Optimal Surfactant Selection For Chemical Enhanced Oil Recovery In Low Temperature, Low Salinity, High Hardness Reservoirs, Christian D. White, Ryan A. Mulvenna, Rituraj Borgohain, Cliff Johnston, Bryan Boudouris

The Summer Undergraduate Research Fellowship (SURF) Symposium

Based on the environmental properties of a crude oil reservoir, only 20-30 % of oil product can be recovered using primary and secondary extraction methods. The remaining stranded oil can only be recovered via various enhanced oil recovery methods. Chemical enhanced oil recovery (EOR) uses specialty chemicals to extract trapped oil in rock layers by generating in-situ microemulsion in the presence of reservoir brine and oil. In this case study, phase behavior tests are conducted for microemulsion formation between the surfactant solution and the oil. The phase behavior tests model reservoirs with low temperature and low salinity. In order to …

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Temperature Dependence Of Electrical Performance Of Tritium Sourced Betavoltaic Cells, Darrell S. Cheu, Tom Adams, Shripad Revankar Aug 2015

Temperature Dependence Of Electrical Performance Of Tritium Sourced Betavoltaic Cells, Darrell S. Cheu, Tom Adams, Shripad Revankar

The Summer Undergraduate Research Fellowship (SURF) Symposium

There is an increasing need for devices that can be powered for extended periods of time where it is impossible for maintenance or replacement, such as pacemakers, long term space flight or undisturbed sensors for military use. Since 1971, most devices run off a Lithium-Iodide battery, which gives a high amount of power but could only last approximately 2 to 5 years, requiring frequent replacement. However, replacement is unnecessary for betavoltaic cells as they can last at least 20 years. Commercially available tritium betavoltaic cells provided by City Labs Inc. were tested at a temperature range of -50°C to 150°C …

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Effect Of Helium Ions Energy On Molybdenum Surfaces Under Extreme Conditions, Joseph Fiala, Jitendra K. Tripathi, Sean Gonderman, Ahmed Hassanein Aug 2015

Effect Of Helium Ions Energy On Molybdenum Surfaces Under Extreme Conditions, Joseph Fiala, Jitendra K. Tripathi, Sean Gonderman, Ahmed Hassanein

The Summer Undergraduate Research Fellowship (SURF) Symposium

Plasma facing components (PFCs) in fusion devices must be able to withstand high temperatures and erosion due to incident energetic ion radiations. Tungsten has become the material of choice for PFCs due to its high strength, thermal conductivity, and low erosion rate. However, its surface deteriorates significantly under helium ion irradiation in fusion-like conditions and forms nanoscopic fiber-like structures, or fuzz. Fuzz is brittle in nature and has relatively lower thermal conductivity than that of the bulk material. Small amounts of fuzz may lead to excessive contamination of the plasma, preventing the fusion reaction from taking place. Despite recent efforts, …

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3d Printing Nanostructured Thermoelectric Device, Qianru Jia, Collier Miers, Amy Marconnet Aug 2015

3d Printing Nanostructured Thermoelectric Device, Qianru Jia, Collier Miers, Amy Marconnet

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermoelectric materials convert thermal energy to electrical energy and vice versa. Thermoelectrics have attracted much attention and research efforts due to the possibility solving electronic cooling problems and reducing energy consumption through waste heat recovery. The efficiency of a thermoelectric material is determined by the dimensionless figure of merit ZT, which depends on both thermal and electrical properties. Researchers have worked for several decades to improve the ZT, but there had been little progress until nanomaterials and nanofabrication became widely available. Nanotechnology makes the ZT enhancement attainable by disconnecting the linkage between thermal and electrical transport. Printing customized, flexible thermoelectric …

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Molecular Precursors In Aqueous Solution For Cigse Solar Cells, Bethany L. Mcilrath, Rakesh Agrawal, Mark J. Koeper Aug 2015

Molecular Precursors In Aqueous Solution For Cigse Solar Cells, Bethany L. Mcilrath, Rakesh Agrawal, Mark J. Koeper

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thin film solar cells are one of the most promising alternatives to traditional silicon based solar cells. Copper, indium, gallium, and sufur/selenium (CIGS) act as the absorber layer in one type of thin films. CIGS films are preferable to silicon because they can have wider applications, such as flexible solar cells. The highest efficiency CIGS solar cells have been made using either expensive vacuum equipment or highly toxic chemicals. This study investigates non-toxic molecular precursor solutions deposited by spray coating. Stoichiometric amounts of CIGS are dissolved in ammonium thioglycolate and ammonium hydroxide to create the molecular precursor solution. This solution …

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Viewing The Extracellular Matrix: An Imaging Method For Tissue Engineering, Michael Drakopoulos, Sarah Calve Aug 2015

Viewing The Extracellular Matrix: An Imaging Method For Tissue Engineering, Michael Drakopoulos, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

The field of regenerative medicine seeks to create replacement tissues and organs, both to repair deficiencies in biological function and to treat structural damage caused by injury. Scaffoldings mimicking extracellular matrix (ECM), the structure to which cells attach to form tissues, have been developed from synthetic polymers and also been prepared by decellularizing adult tissue. However, the structure of ECM undergoes significant remodeling during natural tissue repair, suggesting that ECM-replacement constructs that mirror developing tissues may promote better regeneration than those modeled on adult tissues. This work investigated the effectiveness of a method of viewing the extracellular matrix of developing …

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Identifying And Correcting Biases In Digital Image Correlation At Multiple Length Scales, Catalina Parada, Alberto W. Da Silva Mello, Michael D. Sangid, Hannah K. Woods, Samuel E. Otto Aug 2015

Identifying And Correcting Biases In Digital Image Correlation At Multiple Length Scales, Catalina Parada, Alberto W. Da Silva Mello, Michael D. Sangid, Hannah K. Woods, Samuel E. Otto

The Summer Undergraduate Research Fellowship (SURF) Symposium

Accurate strain measurement at grain and sub-grain levels is important to predict and understand crack initiation during fatigue of materials. During cyclic loading, low magnitude strain is accumulated in the material and any distortion in the images can lead to inaccurate strain measurements and false prediction of the material’s behavior. Digital Image Correlation (DIC) is a reliable tool used to measure strain localization by correlating images before, during, and after cyclic loading. DIC tracks the deformation of nano/micro-scale patterns placed on the surface of the specimens to determine strain fields. However, DIC software does not account for biases due to …

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