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Purdue University

2013

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Articles 31 - 60 of 499

Full-Text Articles in Engineering

Prism - Materials Simulation Tool, Ryan Widjaja, Marisol Koslowski Oct 2013

Prism - Materials Simulation Tool, Ryan Widjaja, Marisol Koslowski

The Summer Undergraduate Research Fellowship (SURF) Symposium

MEMS (Micro-electromechanical System) is a combined electrical and mechanical nano-scaled device with rapidly growing applications. We have developed a contacting radio frequency capacitive MEMS that is commonly used as capacitive switches and contact actuators in PRISM (Prediction of Reliability, Integrity and Survivability of Microsystems) lab at Purdue University. Our research team has focused on creating a simulation of MEMS’s survivability towards crazing and cracking. Our particular objective in this project is to create a tool that can help users perform complex quantitative calculations regarding the properties of different materials. This tool will generate various plots visualizing the properties, such as …

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Driftwatch Pollinator Mapping Application, Shreyas G. Sundararaman, Larry Theller, Bernard Engel Oct 2013

Driftwatch Pollinator Mapping Application, Shreyas G. Sundararaman, Larry Theller, Bernard Engel

The Summer Undergraduate Research Fellowship (SURF) Symposium

Over 65% percent of food consumed in the United States is pollinated by bees. Unfortunately, due to poor farming practices, pesticides are sprayed in bee sensitive areas unknowingly and as a result, the bee population is dwindling at an alarming rate. With lesser bees to pollinate crops, produce is compromised on a very large scale and this could have disastrous impacts on the nation's needs for food. Apiarists and beehive owners face the major responsibility of ensuring that their hives aren't affected by dangerous insecticides and pesticides from the farming areas that they might visit during their crop pollination cycles …

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Nanohub - Crystal Viewer 2.0, Kevin Margatan, Gerhard Klimeck Oct 2013

Nanohub - Crystal Viewer 2.0, Kevin Margatan, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

nanoHUB is an online compilation of tools for simulations. Equipped with 3-D simulations and a capability to solve very complex calculations, nanoHUB provides its users worldwide with various tools to help them finish their assignments. One of the tools available is called a Crystal Viewer Tool, an advanced crystal visualization tool. This tool allows users to generate various crystal types including their every single detail. Currently, a newer version, called Crystal Viewer 2.0, is being tested prior to its release. However, this tool is lacking some important features and a GUI that is not as user friendly as expected. The …

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Two-Equation Two-Fluid Model For Bubbly Flow In A Vertical Channel, Jeffrey Feliszak, Martin Bertodano Oct 2013

Two-Equation Two-Fluid Model For Bubbly Flow In A Vertical Channel, Jeffrey Feliszak, Martin Bertodano

The Summer Undergraduate Research Fellowship (SURF) Symposium

The one-dimensional two-fluid model is widely acknowledged as the most detailed and accurate macroscopic formulation of the thermo-fluid dynamics in nuclear reactor safety analysis. Several thermo-fluid dynamics codes have sprung up based on the one dimensional two-fluid model, such as RELAP5, TRAC, RETRAN, CATHARE, etc. However, these codes are quasi-steady because they lack the short wavelength models that are necessary to make the models well-posed; therefore they must rely on excessive numerical viscosity. Not utilizing short wavelength models causes small wavelength waves to grow quickly to infinity. The project objective is to develop a drafting force model for a one …

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Finite-Difference Time-Domain Simulation Of Photovoltaic Structures Using A Graphical User Interface For Meep, Xin Tze Tee, Peter Bermel Oct 2013

Finite-Difference Time-Domain Simulation Of Photovoltaic Structures Using A Graphical User Interface For Meep, Xin Tze Tee, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

There is a large and growing need for accurate full-wave optical simulations of complex systems such as photovoltaic (PV) cells, particularly at the nanoscale. A finite-difference time-domain tool known as MEEP offers this capability in principle, through C++ libraries and the Scheme programming language. For expert users, this approach has been quite successful, but there is also great interest from new and less frequent users in starting to use MEEP. In order to facilitate this process, we have developed a graphical user interface (GUI) for MEEP, geared toward simulation of 2D and 3D PV cell geometries, freely available through a …

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Set-Up Of Digital Image Correlation Apparatus, German A. Parada, Michael Sangid Oct 2013

Set-Up Of Digital Image Correlation Apparatus, German A. Parada, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

Digital Image Correlation (DIC) is a valuable and customizable experimental technique employed to analyze localized strain regions on materials by tracking the displacement of points on the surface of the studied material under applied stress. To investigate materials behavior, it is vital to correctly set-up the DIC apparatus so work has been done to ready the equipment to start measurements on two distinct projects. On the first project, the fatigue crack behavior of a high-strength aluminum alloy will be studied by cyclic loading, testing necessary for the safe design of aircraft parts utilizing this novel alloy. DIC will be carried …

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Crystalline Cellulose – Atomistic Modeling Toolkit, Mateo Gomez, Pablo Zavattieri Dr. Oct 2013

Crystalline Cellulose – Atomistic Modeling Toolkit, Mateo Gomez, Pablo Zavattieri Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Nature has created efficient strategies to make materials with hierarchical internal structure that often exhibit exceptional mechanical properties. One such example is found in cellulose, in fact it is eight times stronger than stainless steel and advantage is that cellulose incredibly cheap, because processing is obtained from purified wood pulp (it is environmental friendly). The most prevalent modeling technique to study the fundamental mechanical behavior of the crystalline cellulose has been Molecular Dynamics (MD). As a predictive tool, MD allows us to study the behavior of crystalline cellulose at the atomic level, and as such, it accurately predicts the crystalline …

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Phase-Field Dislocation Dynamics Code Optimization, Jaime A. Perez, Marisol Koslowski Oct 2013

Phase-Field Dislocation Dynamics Code Optimization, Jaime A. Perez, Marisol Koslowski

The Summer Undergraduate Research Fellowship (SURF) Symposium

The importance of the study of nanocrystalline materials has gained a huge amount of attention these years due to its extraordinary mechanical, electrical and chemical properties. One significant way to progress in this field is by simulating the behavior of the particles in nano scale, which is not only a need but a challenge due to massive interactions that occur there. The phase-field dislocation dynamics (PFDD) method has been successfully employed in the modeling of plastic deformation, creep and grain boundary sliding. In PFDD, the plastic strain and the energy are functions of phase fields that obey a set of …

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Evolution Of Laser Produced Aluminum Plasma In The Presence Of A Transverse Magnetic Field, Nicholaus Mckenna, Niral Shah, Faisal Odeh, Prasoon Diwakar, Fillipo Genco, Sivanandan Harilal, Syed Hassan, Ahmed Hassanein Oct 2013

Evolution Of Laser Produced Aluminum Plasma In The Presence Of A Transverse Magnetic Field, Nicholaus Mckenna, Niral Shah, Faisal Odeh, Prasoon Diwakar, Fillipo Genco, Sivanandan Harilal, Syed Hassan, Ahmed Hassanein

The Summer Undergraduate Research Fellowship (SURF) Symposium

Surface erosion of plasma-facing components is a very important problem in fusion reactors. In order to make fusion reactors economically viable the lifetime of plasma-facing components must be extended. My research entails using magnetic field interactions with plasma in order to determine how the plasma moves through the field, and if it can be stopped by using a certain orientation of magnetic field. A magnetic field should be able to alter the path of evolving plasma due to the interaction of the magnetic field with the charged particles in the plasma. The optimal orientation for slowing the evolution of the …

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Advanced Visualization Techniques Of Hot-Jet Combustion Of Lean And Ultra-Lean Substances, Timothy I. Machin, Li Qiao Oct 2013

Advanced Visualization Techniques Of Hot-Jet Combustion Of Lean And Ultra-Lean Substances, Timothy I. Machin, Li Qiao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Research has been conducted on ignition of natural gas as a potential replacement for fossil fuels. A reason natural gas is not widely used and adapted is because of the harmful emissions created when combusted in rich mixtures, but if the gas can be burned at a lean or ultra-lean equivalence ratio, these emissions can be reduced or even eliminated. One method of burning lean and ultra-lean substances is by use of hot-jet ignition. This method ignites the substance near its combustion temperature, reducing the harmful emissions. This method is not yet fully understood, and so research must be done …

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Prediction Of Fiber Orientation In Compression Molded Parts Of Short-Fiber-Reinforced Thermoplastics, Anshuman Jagtap, R Byron Pipes, Chris Schwall, Ethan Brubaker Oct 2013

Prediction Of Fiber Orientation In Compression Molded Parts Of Short-Fiber-Reinforced Thermoplastics, Anshuman Jagtap, R Byron Pipes, Chris Schwall, Ethan Brubaker

The Summer Undergraduate Research Fellowship (SURF) Symposium

Short Fiber molded thermoplastics like poly ether ketone ketone (PEKK) have the potential to be used to build reinforcement structures for next generation air crafts. Because of the anisotropic properties of these fibers, it is necessary to know the orientation of fibers in molded parts to determine the strength of parts. The goal of the project is to prepare samples that will be used to determine the spatial distribution of fibers as a function of the parts thickness and for comparison with computer generated models to test for accuracy. Using a full factorial method the effects of four key control …

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Ion Beam Sputtering Yield Measurements By Quartz Crystal Microbalance, Norris W. Watkins Ii, Kaitlyn Grundy, Ahmed Hassanein, Theodore J. Novakowski, Al-Montaser Ba Al-Ajlony, Mark Catalfano, Sivanandan Harilal Oct 2013

Ion Beam Sputtering Yield Measurements By Quartz Crystal Microbalance, Norris W. Watkins Ii, Kaitlyn Grundy, Ahmed Hassanein, Theodore J. Novakowski, Al-Montaser Ba Al-Ajlony, Mark Catalfano, Sivanandan Harilal

The Summer Undergraduate Research Fellowship (SURF) Symposium

Quartz-crystal microbalance (QCM) has been used as a sensitive device for the measurement of small mass changes for a long ago. In fact, using QCM we can measure the differential sputtering yield profile of a material, over a hemisphere above the target, very precisely. The sputtering yield depends on properties of both the incident ions (energy, mass, and incidence angle) and the target (mass, surface binding energy, surface topography, and even the crystal orientation). In our present study, we used a highly sensitive QCM to detect the mass change of the electrode material (gold and silver) through oscillations and calculated …

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Testing Self Healing Properties In Polymers, Hamsini Gopalakrishna, John Blendell Oct 2013

Testing Self Healing Properties In Polymers, Hamsini Gopalakrishna, John Blendell

The Summer Undergraduate Research Fellowship (SURF) Symposium

Mussels and barnacles have the ability to stick to underwater surfaces with the help of a cross-linked protein structure. Reduction in the plastic consumption can be achieved by using toughened polymers. Synthesized cross-linking polymers can be used for underwater adhesion by mimicking the protein structure used by mussels and barnacles. One such polymer is poly(3,4-dihydroxystyrene-co-styrene) having enhanced toughness. Traditionally, blister tests measure the adhesion between a substrate to a surface but this was modified to serve as the driving force to drive crack propagation in controlled flaws. The modified blister tests were carried out on polystyrene (PS) samples. Once the …

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Dna Based Carbon Nanotube Porphyrin Nanohybrids Molecular Recognization And Regeneration, Molly M. Riccitelli, Hanyu Zhang, Jong Hyun Choi Oct 2013

Dna Based Carbon Nanotube Porphyrin Nanohybrids Molecular Recognization And Regeneration, Molly M. Riccitelli, Hanyu Zhang, Jong Hyun Choi

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the search to improve solar cells, scientists are exploring new materials that will provide better current transfer. One material that has emerged as a strong contender is the single walled carbon nanotube (SWNT). Current DNA-SWNT based films combined with chromophores have poor operational lifetimes compared to commercial solar cells. Once exposed to light the chromophore begins to degrade, eventually rendering the solar cell unusable. To solve this problem, we used a method involving multiple steps. First we found which DNA sequences formed structures around the SWNT that could hold the most chromophores by using a spectrophotometer to test the …

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Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi Oct 2013

Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi

The Summer Undergraduate Research Fellowship (SURF) Symposium

Motor proteins such as kinesin move along microtubules in order to transport cellular cargos throughout the cell by obtaining energy from RNA hydrolysis which allows the cell to complete the tasks needed to stay alive. In this work, we developed synthetic molecular motors using DNA enzymes (DNAzyme) and fluorescent nanomaterials which mimic the functions and structures of motor proteins. A DNAzyme-capped CdS nanoparticle and a RNA-functionalized single-walled carbon nanotube (SWCNT) were used as a walker and a track in the motor platform, respectively. As a walking mechanism, the DNAzyme cleaved the RNA substrates in the presence of metal cations. The …

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A Generalized Design For Affinity Chromatography Columns, Lee-Wei Kao, Nien-Hwa Linda Wang Oct 2013

A Generalized Design For Affinity Chromatography Columns, Lee-Wei Kao, Nien-Hwa Linda Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

In affinity chromatography, an adsorbent with a high selectivity for a target solute is used to isolate the target molecule from other impurities. With sufficient selectivity, the target molecule can be isolated in a highly purified and concentrated state. Common applications of affinity chromatography include Protein A chromatography for antibody purification and Immobilized Metal Affinity Chromatography (IMAC) for protein purification. The well-known design method based on constant-pattern mass transfer zone analysis does not apply to small feed batches, which are insufficient to form constant-pattern frontal waves. Other literature design methods rely on simulation or experimental trials that can be time-consuming …

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Is Real-Time Mobile Content-Based Image Retrieval Feasible?, Colin G. Graber, Anup Mohan, Yung-Hsiang Lu Oct 2013

Is Real-Time Mobile Content-Based Image Retrieval Feasible?, Colin G. Graber, Anup Mohan, Yung-Hsiang Lu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Content-based image retrieval (CBIR) is a method of searching through a database of images by using another image as a query instead of text. Recent advances in the processing power of smart phones and tablets, collectively known as mobile devices, have prompted researchers to attempt to construct mobile CBIR systems. Most of the research that has been conducted on mobile CBIR has focused on improving either its accuracy or its run-time, but not both simultaneously. We set out to answer the question: is real-time CBIR with manageable accuracy possible on current mobile devices? To find the answer to this question, …

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Absorption Simulation ( Absim ) Software Development, Vipul Vishnu Bhat, Ming Qu Oct 2013

Absorption Simulation ( Absim ) Software Development, Vipul Vishnu Bhat, Ming Qu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Researchers working on air conditioning systems currently use a software called ABSIM ( Absorption Simulation ) to evaluate current absorption systems or simulate new system designs. ABSIM was developed at Oak Ridge National Labs in the 1980s and the latest platform it is compatible with is Windows XP. ABSIM is not compatible on newer platforms and is not very user friendly. A lot of the actions involved in using ABSIM aren’t very intuitive. The goal is to develop a more user friendly simulation program that is based off of ABSIM and see to it that the program can be deployed …

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Silver Oxide-Graphene Sensor For Hydrogen Peroxide, Austin D. Scherbarth, L Stanciu Oct 2013

Silver Oxide-Graphene Sensor For Hydrogen Peroxide, Austin D. Scherbarth, L Stanciu

The Summer Undergraduate Research Fellowship (SURF) Symposium

A nonenzymatic, amperometric sensor for Hydrogen Peroxide (H2O2) was designed by drop coating glassy carbon electrodes (GCEs) with Silver Oxide (Ag2O). Combining Ag2O with Graphene Oxide and a polymer, PEDOT, was also attempted in order to increase stability and electrochemical properties. Using metal oxides along with Graphene Oxide for sensors has been done quite a bit, but Ag2O itself has not been research extensively. So, in order to produce the best H2O2 sensor, the configuration of all components had to be optimized. Three different Ag2O …

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Mems Lab Simulation Tool, Oluwatosin D. Adeosun, Sambit Palit, Ankit Jain, Muhammad A. Alam Oct 2013

Mems Lab Simulation Tool, Oluwatosin D. Adeosun, Sambit Palit, Ankit Jain, Muhammad A. Alam

The Summer Undergraduate Research Fellowship (SURF) Symposium

MEMS actuators have multiple design applications. Understanding their behavior as well as the ability to predict their actuation characteristics and voltage response is important when designing these actuators. In order to know these devices will behave, designers have to solve multiple analytical equations and experiments that can be very time consuming. Over the course of the summer a tool was created on nanoHUB that will allow users to enter information about a MEMS actuator and provide the voltage response of the actuator. To create the tool, scaling equations were first provided for various geometry configurations and the equations were next …

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Intermetalic Growth Rate In Transient Liquid Phase Sintering Of Pb-Free Solder Interconnects, Shuqing Zhang, John Blendell Oct 2013

Intermetalic Growth Rate In Transient Liquid Phase Sintering Of Pb-Free Solder Interconnects, Shuqing Zhang, John Blendell

The Summer Undergraduate Research Fellowship (SURF) Symposium

Following the electron devices are widely used in daily life, Pb-free solder alloy, as the replacement of Pb solder joint material, needs extensive researches to observe the properties for using and simulation purpose. Solder are used as the joint to connect two work pieces in printed wiring board of electronics. Most lead-free solders comprise tin (Sn) as the majority component, and nominally pure b-Sn is the majority phase in the microstructure of these solders. The most important thing for solder joint that researchers care about is its life cycle. Due to the incomplete of the mechanical profile of Pb-free solder …

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Design Of A Novel Actuation System For Variable Displacement Gear Machine, Mark W. Mahuren, Andrea Vacca Oct 2013

Design Of A Novel Actuation System For Variable Displacement Gear Machine, Mark W. Mahuren, Andrea Vacca

The Summer Undergraduate Research Fellowship (SURF) Symposium

External spur gear pumps are exceedingly useful components in common hydraulic systems. The main issue with external gear pumps is that all current models are limited to only fixed-displacement. This means that for every revolution of the gears inside the pump, a set amount of fluid will always be displaced. Consequently, external gear pumps are limited in their use because they can only operate at full throttle causing inefficiencies when reduced displacement is needed. The successful procurement of a variable displacement gear pump will allow a more efficient use of hydraulic systems, such as in the displacement controlled systems used …

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Effect Of Compression On The Transmission Loss Of Porous Material, Yingchao Yang, J Stuart Bolton Oct 2013

Effect Of Compression On The Transmission Loss Of Porous Material, Yingchao Yang, J Stuart Bolton

The Summer Undergraduate Research Fellowship (SURF) Symposium

Porous materials are commonly applied in sound absorption in different places. Transmission loss, one of the vital parameters determining the performance of the material, will change when the material is compressed. Usually the compression that might affect the properties to the greatest extent are normal compression and the deformation can be simplified as 1D compression model. In order to verify the prediction, some formulas taking several parameters (porosity, tortuosity, flow resistivity and characteristic lengths) into account are applied and also the Johnson et al’s model of limp structure. Dynamic density of limp model and bulk modulus are thus obtained and …

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Bicistronic Design For Precise And Reliable Gene Expression, Nidhi N. Menon, Jenna Rickus Oct 2013

Bicistronic Design For Precise And Reliable Gene Expression, Nidhi N. Menon, Jenna Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Despite having progressed extensively in the field of synthetic biology in terms of DNA synthesis, analysis and transplanting, we still cannot reliably, quantitatively measure expression of new genetic constructs. We engineered a biobrick compatible expression cassette to control transcription and translation initiation which can be reused in new genetic contexts. Previous research has shown that the Bicistronic design have much lesser variations in expression with varying genes of interest as compared to the regular monocistronic design.(Mutalik, Endy, Guimaraes, Cambray, Lam, Juul, Tran & Paull, 2013) The Bicistronic design(BCD) consists of two Shine-Dalgarno sequences in its translation element which when combined …

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Synthesizing Bismuth Telluride Nanowires In A Large Scale And Investigating The Energy Filtering Effect By Blending Bismuth Telluride Nanowires And Silver Nanoparticle In Thermoelectrics, Henka Darsono, Haiyu Fang, Yue Wu Oct 2013

Synthesizing Bismuth Telluride Nanowires In A Large Scale And Investigating The Energy Filtering Effect By Blending Bismuth Telluride Nanowires And Silver Nanoparticle In Thermoelectrics, Henka Darsono, Haiyu Fang, Yue Wu

The Summer Undergraduate Research Fellowship (SURF) Symposium

More than 50% of the energy sources becomes “waste” energy generally dissipated to the atmosphere in the form of heat. Thermoelectric effect is a conversion of temperature difference to electric voltage and can be used to convert the wasted heat to useful work. Nanomaterials have great potentials in the field of thermoelectric effect since they have properties that can allow higher efficiency in converting this wasted heat to electricity as compared to bulk materials. The purpose of this project is to develop a method to synthesize bismuth telluride (Bi2Te3) nanowires on a large scale and incorporate …

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Collimation Effects On Magnetically Confined Laser Produced Plasmas, Niral Shah, Nick Mckenna, Faisal Odeh, Prasoon Diwakar, Fillipo Genco, Sivanandan Harilal, Syed Hassan, Ahmed Hassanein Oct 2013

Collimation Effects On Magnetically Confined Laser Produced Plasmas, Niral Shah, Nick Mckenna, Faisal Odeh, Prasoon Diwakar, Fillipo Genco, Sivanandan Harilal, Syed Hassan, Ahmed Hassanein

The Summer Undergraduate Research Fellowship (SURF) Symposium

Tokamaks for fusion research are extremely complex and are still limited by inherent instabilities such as material erosion from plasma instabilities. Due to the lack of data and high demand of resources, simulations to portray Tokamaks are essential. A Particle-In-Cell (PIC) simulation for plasma erosion on materials within the Tokamak is to be benchmarked using the experimental data obtained in these experiments. The effects of an axial magnetic field (magnetic field lines are along the plasma propagation direction) on an expanding laser produced plasma plume are investigated. A Continuum Surelite Nd:YAG laser system at 1064 nm wavelength and 6 ns …

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Characterization Of Lead-Free Piezo-Ceramics, Hanhan Zhou, John Blendell Oct 2013

Characterization Of Lead-Free Piezo-Ceramics, Hanhan Zhou, John Blendell

The Summer Undergraduate Research Fellowship (SURF) Symposium

Lead zirconate titanate (PZT) has been the most commonly used piezoelectric material due to its high piezoelectric performance under varied operating conditions. However, it has been noticed that the lead component is toxic, causing some environmental issues and a lead free substitute material was introduced. The substituted environmental friendly piezoelectric material, Ba(Zr0.2Ti0.8)O3–x(Ba0.7Ca0.3)TiO3 (BZT-xBCT) system that can fulfill the need of high piezoelectricity has been developed. The research was conducted to characterize the BZT-xBCT system with five different compositions (x=0.06, 0.08, 0.1, 0.12 and 0.14).. XRD was applied to examine the crystal structure of the samples before and after poling and …

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High-Order Shock Capturing For Computational Aeroacoustics, Samuel Otto, Gregory Blaisdell Oct 2013

High-Order Shock Capturing For Computational Aeroacoustics, Samuel Otto, Gregory Blaisdell

The Summer Undergraduate Research Fellowship (SURF) Symposium

Jet noise is not only an annoyance to passengers and communities near airports, it is a major contributor to hearing loss in veterans who served on aircraft carriers, as well as a significant limiting factor for the growth of commercial airlines. High-fidelity large eddy simulation (LES) is an important tool for analyzing and predicting jet noise; however the utilized non-dissipative high order finite difference schemes produce instabilities at shock waves. Schemes for capturing shock waves, however, are more dissipative and do a poor job preserving turbulent structures and acoustic waves. To maximize the strengths of both approaches, hybrid methods utilize …

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Characterization Of Hardness And Elastic Modulus Of A Pharmaceutical Material For Multiple Crystal Orientations, Alexis L. Mertz, David F. Bahr Oct 2013

Characterization Of Hardness And Elastic Modulus Of A Pharmaceutical Material For Multiple Crystal Orientations, Alexis L. Mertz, David F. Bahr

The Summer Undergraduate Research Fellowship (SURF) Symposium

Nanoindentation has made it possible to test material properties of extremely brittle molecular crystals, which include many pharmaceuticals. An antifungal, griseofulvin, is tested to determine differences in hardness and elastic modulus for different crystal orientations. Hardness and elastic modulus are determined by nanoindentation on single crystals that are rotated in 15° intervals. There are differences in hardness at rotation degrees of 45°, 60°, and 75° from the 0° orientation and differences in elastic modulus at rotation degrees of 15°, 60°, and 75° from the 0° orientation. It is also found that the elastic modulus and hardness values of the 75° …

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Pvpanel Sim 2.0 – Pv Module Simulation With Improved Device Physics, Mario Rentería Piñón, Muhammad A. Alam Oct 2013

Pvpanel Sim 2.0 – Pv Module Simulation With Improved Device Physics, Mario Rentería Piñón, Muhammad A. Alam

The Summer Undergraduate Research Fellowship (SURF) Symposium

Efficiency is a crucial parameter to consider when fabricating thin film (TF) photovoltaic panels because there is a significant efficiency drop between lab scale cells and large modules. PVpanel Sim is a circuit simulation using SPICE tool which combines the effects of the major reasons of efficiency reduction, like shunt leakages and sheet resistance, with external factors like irradiance and the effects of shadowing in order to provide the user with a better understanding of how a solar panel would behave. For the current version of the tool a basic equivalent model for individual cells is used with ideal components, …

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