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Msu Xtreme: Minnesota State University, Mankato's Entry Into The "Clean Snowmobile Challenge 2001", Scott Betcher, Allen Caldwell, Nathan Lindeman, Brian Mandelkow, Dave Maniak, Randy Rohlf, James Skuya, Dennis Swanson, Aaron Wolff, Mark Brandl, Dan Dobesh, Ryan Erickson, Jeff Gillen, Jan Smith, Jason Wilkie 2014 Minnesota State University, Mankato

Msu Xtreme: Minnesota State University, Mankato's Entry Into The "Clean Snowmobile Challenge 2001", Scott Betcher, Allen Caldwell, Nathan Lindeman, Brian Mandelkow, Dave Maniak, Randy Rohlf, James Skuya, Dennis Swanson, Aaron Wolff, Mark Brandl, Dan Dobesh, Ryan Erickson, Jeff Gillen, Jan Smith, Jason Wilkie

Journal of Undergraduate Research at Minnesota State University, Mankato

Minnesota State University, Mankato’s Automotive Engineering Technology program formed a team to enter the Clean Snowmobile Challenge 2001. Selections for the organization’s machine included a 2001 Polaris Edge Chassis specially outfitted with a 2000 500 cc two-stroke Polaris engine. Modifications to the snowmobile were made specifically for Clean Snowmobile Challenge 2001 events. Acceleration, emissions, cold start, noise, fuel economy/range, handling/drivability, hill climb, and static display made up the list of events featured in the competition. MSU Xtreme has modified the snowmobile in every area with special emphasis on emissions and handling. Testing and analysis of the ...


Surface Modification Of Aluminum Alloys By Plasma Electrolytic Oxidation, Vahid Dehnavi 2014 Western University

Surface Modification Of Aluminum Alloys By Plasma Electrolytic Oxidation, Vahid Dehnavi

University of Western Ontario - Electronic Thesis and Dissertation Repository

Plasma Electrolytic Oxidation (PEO) is a surface treatment for the production of ceramic oxide coatings with great properties, such as high wear and corrosion resistance, on metal substrates, particularly aluminum and magnesium alloys. Formation of PEO coatings involves complex processes and mechanisms that are difficult to study. Currently, the PEO process is in a transition phase from research to commercial application, with a primary focus on the corrosion and wear protection of light alloys, and has recently generated interest as a promising surface treatment for biomedical applications.

To justify the industrial application of PEO, a more systematic and in-depth study ...


On The Interfacial Fracture Mechanics Of Long-Fibre Reinforced Polymer Composites, Ian N. Swentek 2014 Western University

On The Interfacial Fracture Mechanics Of Long-Fibre Reinforced Polymer Composites, Ian N. Swentek

University of Western Ontario - Electronic Thesis and Dissertation Repository

Fibre-reinforced polymer composites are being widely adopted as the de facto material for automotive lightweight design, but lack the material models capable of accurately predicting fracture. To address this research gap, three large-scale experimental studies are undertaken to characterize thermoset polymers during cure, understand the fibre-matrix interfacial bond strength, and predict the fracture of random long-fibre composites via the energy of fracture. In conjunction with the Fraunhofer Project Center in London, Ontario, sample sheet moulded composites were used to verify the key findings with several industrial composite samples. With refined interfacial strength measurement methods, and accurate predictions of the composite ...


Surfactant Assisted Dispersion Of Single-Walled Carbon Nanotubes In Polyvinylpyrrolidone Solutions, Tennison Yu 2014 Western University

Surfactant Assisted Dispersion Of Single-Walled Carbon Nanotubes In Polyvinylpyrrolidone Solutions, Tennison Yu

University of Western Ontario - Electronic Thesis and Dissertation Repository

Obtaining stable aqueous dispersions is one of the main challenges hindering a widespread and effective use of single-walled carbon nanotubes (SWNT) in many applications. Although it has been recognized that their versatility makes them an extremely attractive material, the unique molecular structure that gives SWNTs their unmatched electronic, mechanical, and thermal properties is also responsible for strong van der Waals interactions. This, combined with extremely high aspect ratios and flexibility, causes SWNTs to adhere strongly into tightly bundled ropes. In these bundles, SWNTs are not as useful as their linearized unbundled equivalents. Thus, in order to take advantage of their ...


Three Dimensional Transient Asymmetric Flowfields In Physical Vapor Transport, Joseph Dobmeier 2014 Minnesota State University, Mankato

Three Dimensional Transient Asymmetric Flowfields In Physical Vapor Transport, Joseph Dobmeier

Journal of Undergraduate Research at Minnesota State University, Mankato

Physical Vapor Transport is a manufacturing process used to produce single crystals of semiconductor materials such as mercurous chloride (Hg2Cl2). In the past this time-varying process has been studied with numerical simulation by considering three dimensional flow using an axi-symmetric two dimensional model or by restricting the simulation to asymmetric two dimensional flow and dropping the assumption of axi-symmetry from the model. It is generally agreed that neither of these methods accurately represent the true behavior of the process. The purpose of this research was to extend the asymmetric two dimensional model to three dimensions thereby obtaining a solution which ...


Highly Visible Light Active Ag@Zno Nanocomposites Synthesized By Gel-Combustion Route, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho 2014 SelectedWorks

Highly Visible Light Active Ag@Zno Nanocomposites Synthesized By Gel-Combustion Route, Mohammad Mansoob Khan Dr, S. A. Ansari, J. Lee, M. H. Cho

Dr. Mohammad Mansoob Khan

Highly visible light active 1% and 3% Ag@ZnO nanocomposites were synthesized via a gel combustion route using citric acid as a fuel. The formation of the nanocomposites with enhanced properties was confirmed using a range of characterization techniques, photocatalysis and photoelectrochemical studies. Compared to the pristine ZnO nanoparticles, the Ag@ZnO nanocomposites exhibited enhanced visible light photocatalytic activity for the degradation of methylene blue and photoelectrochemical response. A mechanism was proposed to account for the photocatalytic activities of the Ag@ZnO nanocomposite that showed the surface plasmon resonance (SPR) of Ag is an effective way of enhancing the visible ...


Development Of A Silicon Nanowire Mask Using Scanning Probe Microscopy, Ross Gregoriev 2014 California Polytechnic State University

Development Of A Silicon Nanowire Mask Using Scanning Probe Microscopy, Ross Gregoriev

Master's Theses and Project Reports

Scanning probe microscopy techniques were used to investigate the desorption of hydrogen passivated silicon to form SiO2 etch masks The application of the etch masks were planned on being used to manufacture silicon nanowires. Low concentration hydrofluoric acid was used to passivate the surface. The surface was selectively depassivated by SPM techniques. Scanning tunneling microscopy (STM) and atomic force microscopy (AFM) were used to create the masks. The STM system used was found to desorb hydrogen from the surface faster than the STM could image and was considered incapable in the configuration investigated. This led to the use of atomic ...


Effects Of Ball Milling And Sintering On Alumina And Alumina-Boron Compounds, Thomas Cross 2014 University of Wisconsin Milwaukee

Effects Of Ball Milling And Sintering On Alumina And Alumina-Boron Compounds, Thomas Cross

Theses and Dissertations

Alumina has a wide variety of applications, but the processing of alumina based materials can be costly. Mechanically milling alumina has been shown to enhance the sintering properties while decreasing the sintering temperature. Additions of boron have also proven to increase sintering properties of alumina. These two processes, mechanical milling and boron additions, will be combined to test the sintering properties and determine if they are improved upon even further compared to the individual processes.

Multiple samples of pure alumina, 0.2 weight percent boron, and 1.0 weight percent boron are batched and processed in a ball mill for ...


A Systematic Study Of The Process-Structure Relationship For Building Polymer Interphase Regions In Carbon Nanotube Composites, Yiying Zhang 2014 Northeastern University

A Systematic Study Of The Process-Structure Relationship For Building Polymer Interphase Regions In Carbon Nanotube Composites, Yiying Zhang

Mechanical Engineering Dissertations

As the world's demands for new high-performance materials continuously grow, reinforcing polymer materials with carbon nanotubes (CNT) to produce lightweight composites with high properties has been pursued since their discovery. However, to date composites with the anticipated superior properties have not been achieved yet. This is mainly due to the lack of fundamental understanding regarding processing these materials as well as manipulating the nano-scale assemblies, which would dictate the desired macroscopic performance.

This dissertation work focuses on understanding the development of interfacial zones in polymer/CNT composites, which is necessary for producing mechanically outstanding composite materials. Highly crystalline and ...


Finite Volume Numerical Analysis Of The Thermal Property Of Cellular Concrete Based On Two And Three Dimensional X-Ray Computerized Tomography Images, She Wei, Yang Yonggan, Xie Deqing, Zhang Yunsheng 2014 Purdue University

Finite Volume Numerical Analysis Of The Thermal Property Of Cellular Concrete Based On Two And Three Dimensional X-Ray Computerized Tomography Images, She Wei, Yang Yonggan, Xie Deqing, Zhang Yunsheng

International Conference on Durability of Concrete Structures

Cellular concrete is one kind of lightweight concrete, which are widely used in thermal insulation engineering project. In this study, a three dimensional (2D and 3D) finite-volume-based models was developed for analyzing the heat transfer mechanisms through the porous structures of cellular concretes under steady-state heat transfer condition and also for investigating the differences between 2D and 3D modeling results. 2D and 3D reconstructed pore networks were generated from the microstructural information measured by a 3D image captured by X-ray computerized tomography (X-CT). In addition, the 3D-computed value of the effective thermal conductivity was found to be in better agreement ...


On Utilization Of Elliptical Rings In Assessing Cracking Tendency Of Concrete, Xiangming Zhou, Olayinka G. Oladiran, Wei Dong 2014 Purdue University

On Utilization Of Elliptical Rings In Assessing Cracking Tendency Of Concrete, Xiangming Zhou, Olayinka G. Oladiran, Wei Dong

International Conference on Durability of Concrete Structures

A new experimental method by utilizing elliptical rings to replace circular rings recommended by ASTM and AASHTO was explored for assessing cracking potential of concrete and other cement-based materials under restrained condition. A series of thin and thick elliptical concrete rings were tested alongside circular ones until cracking. Cracking age, position, and propagation were carefully examined. It is found that thin elliptical rings with appropriate geometry can initiate cracks quicker than circular ones, which is desirable for accelerating the ring test. However, thick elliptical rings seem not to exhibit a desirable geometry effect of accelerating ring test compared with circular ...


The Correlation Of Chloride Diffusion Coefficient And Concrete Maturity Value And Its Application In Hong Kong–Zhuhai–Macao Bridge Engineering, Pengping Li, Shengnian Wang, Jianbo Xiong, Rui Chai, Yu Yan 2014 Purdue University

The Correlation Of Chloride Diffusion Coefficient And Concrete Maturity Value And Its Application In Hong Kong–Zhuhai–Macao Bridge Engineering, Pengping Li, Shengnian Wang, Jianbo Xiong, Rui Chai, Yu Yan

International Conference on Durability of Concrete Structures

The correlation of chloride diffusion coefficient and concrete maturity value within 56 days of curing was investigated by the chemically combined water content method, rapid chloride migration (RCM) test, and concrete maturity test. The experimental results showed that chloride diffusion coefficient of concretes decreased not only with increasing curing ages but also with increasing curing temperature, which can promote the hydration degree of cementitous materials. There is a significant correlation between the chloride diffusion coefficient of indoor cured specimens and the concrete maturity value when expressed as a power function (R2 = 0.976). In addition, the calculated values of ...


Influence Of Controlled Permeability Formwork On The Permeability Of Concrete, Wei Lin, Q. Jiang, J. Liu, J. Liu 2014 Purdue University

Influence Of Controlled Permeability Formwork On The Permeability Of Concrete, Wei Lin, Q. Jiang, J. Liu, J. Liu

International Conference on Durability of Concrete Structures

Corrosion of steel reinforcement related to the intrusion of chloride ion is still the main threats to the durability of concrete structure, especially in marine environment. For the purpose of delaying the Cl concentration at the surface of steel reinforcement reaching the critical value leading to initial corrosion, the permeability of concrete is usually improved by optimizing the concrete mixture to achieve high compatibility as well as optimized pore structure. In recent years, controlled permeability formwork (CPF) which was originally developed to obtain much smoother surface of the concrete proves to promote the service performance of the concrete by enhancing ...


Opto-Electronic Devices With Nanoparticles And Their Assemblies, Chieu Van Nguyen 2014 University of Nebraska - Lincoln

Opto-Electronic Devices With Nanoparticles And Their Assemblies, Chieu Van Nguyen

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

Nanotechnology is a fast growing field; engineering matters at the nano-meter scale. A key nanomaterial is nanoparticles (NPs). These sub-wavelength (< 100nm) particles provide tremendous possibilities due to their unique electrical, optical, and mechanical properties. Plethora of NPs with various chemical composition, size and shape has been synthesized. Clever designs of sub-wavelength structures enable observation of unusual properties of materials, and have led to new areas of research such as metamaterials. This dissertation describes two self-assemblies of gold nanoparticles, leading to an ultra-soft thin film and multi-functional single electron device at room temperature. First, the layer-by-layer self-assembly of 10nm Au nanoparticles and polyelectrolytes is shown to behave like a cellular-foam with modulus below 100 kPa. As a result, the composite thin film (~ 100nm) is 5 orders of magnitude softer than an equally thin typical polymer film. The thin film can be compressed reversibly to 60% strain. The extraordinarily low modulus and high compressibility are advantageous in pressure sensing applications. The unique mechanical properties of the composite film lead to development of an ultra-sensitive tactile imaging device capable of screening for breast cancer. On par with human finger sensitivity, the tactile device can detect a 5mm imbedded object up to 20mm below the surface with low background noise. The second device is based on a one-dimensional (1-D) self-directed self-assembly of Au NPs mediated by dielectric materials. Depending on the coverage density of the Au NPs assembly deposited on the device, electronic emission was observed at ultra-low bias of 40V, leading to low-power plasma generation in air at atmospheric pressure. Light emitted from the plasma is apparent to the naked eyes. Similarly, 1-D self-assembly of Au NPs mediated by iron oxide was fabricated and exhibits ferro-magnetic behavior. The multi-functional 1-D self-assembly of Au NPs has great potential in modern electronics such as solid state lighting, plasma-based nanoelectronics, and memory devices.

Adviser: Ravi F. Saraf


Infrared Transmitting Glasses With High Glass Transition Temperatures, Steve W. Martin 2014 Iowa State University

Infrared Transmitting Glasses With High Glass Transition Temperatures, Steve W. Martin

Iowa State University Patents

A chalcogenide glass capable of infrared transmission which is either sulfur, selenium or tellurium based and consists of compositions of the formula MX+M.sub.2 'X.sub.3 +SiX.sub.2, wherein M is one of the metals calcium, strontium, barium, zinc and lead, and M' is either aluminum or gallium and X is either sulfur, selenium or tellurium. Aluminum or gallium chalcogenide acts to increase the covalent bonding network structure of the glass with the result being that excellent high temperature 8-14 micron IR transmitting glasses with transition temperatures above 500C are prepared.


Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang 2014 SelectedWorks

Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang

AZMAN ISMAIL

The external surface hardness of friction stir welded aluminum alloy 6063 pipe joint was investigated in this paper. The 89mm of outside diameter pipe with 5mm of wall thickness was used as test pipe piece for this experiment on closed butt joint configuration by utilising Bridgeport 2216 CNC milling machine and orbital clamping unit specially designed to cater for this task and function. Several welded samples were produced on varying process parameters which were successfully joined by using a non-consumable tool with a flat shoulder and a cylindrical pin.


Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang 2014 SelectedWorks

Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang

Azman Ismail

The external surface hardness of friction stir welded aluminum alloy 6063 pipe joint was investigated in this paper. The 89mm of outside diameter pipe with 5mm of wall thickness was used as test pipe piece for this experiment on closed butt joint configuration by utilising Bridgeport 2216 CNC milling machine and orbital clamping unit specially designed to cater for this task and function. Several welded samples were produced on varying process parameters which were successfully joined by using a non-consumable tool with a flat shoulder and a cylindrical pin.


Wetting And Reactivity Of Active Metal Braze Alloys On Tungsten Carbide, Hayden Peck, Alan Meier, Ph.D. 2014 Montana Tech Library

Wetting And Reactivity Of Active Metal Braze Alloys On Tungsten Carbide, Hayden Peck, Alan Meier, Ph.D.

2014 Summer Poster Symposium

Background

Tungsten carbide is useful because of its hardness and strength. Joining of dissimilar materials especially non-metallic materials is very challenging. Active metals such as titanium can be added to a ductile filler metals such as copper to get wetting via a reduction reaction.

Conclusions

All alloy conditions wet the tungsten carbide/cobalt substrates. Two different interfacial reaction types were observed: dissolution and reduction reactions. An important issue has been identified: the braze interface reactions change the chemistry of the braze alloy which change the interaction between the braze alloy and the other material substrate.


Use Of Liquid Pressure-Pulse Decay Permeameter In Experimental Evaluation Of Permeability In Wellbore Cement Under Geopressured Geothermal Conditions, Kolawole Bello, Mileva Radonjic 2014 Engineering Conferences International

Use Of Liquid Pressure-Pulse Decay Permeameter In Experimental Evaluation Of Permeability In Wellbore Cement Under Geopressured Geothermal Conditions, Kolawole Bello, Mileva Radonjic

5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry

Geopressured reservoirs in the northern Gulf of Mexico basin along the coast of Louisiana have been determined to be viable source of geothermal energy and potential sites for carbon sequestration, where CO2 can be utilized to induce convective flow of geofluids and enhance heat harvesting. These reservoirs are made of unconsolidated sandstone capped by shale layers and possess temperatures as high as 140⁰C. At high temperatures, cement strength retrogression occur when calcium silicate hydrate phase in hydrated cement converts to alpha dicalcium silicate hydrate phase. The higher the temperature, the quicker the rate of transformation of calcium silicate hydrate. The ...


Numerical Solution Of Burgers' Equation Arising In Longitudinal Dispersion Phenomena In Fluid Flow Through Porous Media By Crank-Nicolson Scheme, Ravi Borana, Vikas Pradhan, Manoj Mehta 2014 Engineering Conferences International

Numerical Solution Of Burgers' Equation Arising In Longitudinal Dispersion Phenomena In Fluid Flow Through Porous Media By Crank-Nicolson Scheme, Ravi Borana, Vikas Pradhan, Manoj Mehta

5th International Conference on Porous Media and Their Applications in Science, Engineering and Industry

The present paper discusses the numerical solution of the Burgers’ equation arising in longitudinal dispersion phenomenon in fluid flow through porous media. In the porous medium pure water, salt water or contaminated water disperse in longitudinal direction gives rise to a non-linear partial differential equation in the form of Burgers’ equation. The equation is solved by using Crank-Nicolson finite difference scheme with appropriate initial and boundary conditions. The longitudinal dispersion phenomenon may be miscible or immiscible fluid flow through porous media. The problem of miscible displacement can be seen in the coastal areas, where fresh water beds are gradually displaced ...


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