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Full-Text Articles in Materials Science and Engineering

Free-Troposphere Ozone And Carbon Monoxide Over The North Atlantic For 2001-2011, Aditya Kumar, S. Wu, M. F. Weise, R. Honrath, R. C. Owen, D. Helmig, L. Kramer, M. Val Martin, Q. Li Dec 2013

Free-Troposphere Ozone And Carbon Monoxide Over The North Atlantic For 2001-2011, Aditya Kumar, S. Wu, M. F. Weise, R. Honrath, R. C. Owen, D. Helmig, L. Kramer, M. Val Martin, Q. Li

Michigan Tech Publications

In situ measurements of carbon monoxide (CO) and ozone (O3) at the Pico Mountain Observatory (PMO) located in the Azores, Portugal, are analyzed together with results from an atmospheric chemical transport model (GEOS-Chem) and satellite remote sensing data (AIRS (Atmospheric Infrared Sounder) for CO, and TES (Tropospheric Emission Spectrometer) for O3) to examine the evolution of free-troposphere CO and O3 over the North Atlantic for 2001-2011. GEOS-Chem captured the seasonal cycles for CO and O3 well but significantly underestimated the mixing ratios of CO, particularly in spring. Statistically significant (using a significance level of 0.05) decreasing trends were found for …


Mse Annual Report 2013, Department Of Materials Science And Engineering, Michigan Technological University Jan 2013

Mse Annual Report 2013, Department Of Materials Science And Engineering, Michigan Technological University

Department of Materials Science and Engineering Annual Reports

Table of Contents

  • Paul Sanders, Project-Oriented Learning
  • A New Way to Prevent Deadly Infections
  • 3D Printers for Peace and Progress
  • Faculty and Staff News
  • Graduate Student Update
  • Outreach
  • Undergraduate Student News
  • Alumni at a Glance


Faulted Structures In Li Ion Exchanged Namo2 (M=Ni(0.25)Mn(0.75)), Aaron M. Dewahl Jan 2013

Faulted Structures In Li Ion Exchanged Namo2 (M=Ni(0.25)Mn(0.75)), Aaron M. Dewahl

Dissertations, Master's Theses and Master's Reports - Open

A family of LiMO2 materials (M=Ni0.25Mn0.75) was prepared from Na1.2-xLixMO precursors (0≤x≤0.6) via ion exchange. The resulting IE products were examined via XRD and compared to simulated XRD patterns produced using DIFFax to determine the defect structures resulting from the IE process. For the 0.1≤x≤0.6 materials, it is observed that there are 3 LiMO2 sub-phases with different Li contents present. As the amount of Li in the precursor increases, the amount of each phase changes resulting in a net shift to higher 2-theta; corresponding to an overall decrease in lattice …


Molecular Modeling Of Pmr-15 Polyimide, Fnu Pruthul Kokkada Ravindranath Jan 2013

Molecular Modeling Of Pmr-15 Polyimide, Fnu Pruthul Kokkada Ravindranath

Dissertations, Master's Theses and Master's Reports - Open

PMR-15 polyimide is a polymer that is used as a matrix in composites. These composites with PMR-15 matrices are called advanced polymer matrix composite that is abundantly used in the aerospace and electronics industries because of its high temperature resistivity. Apart from having high temperature sustainability, PMR-15 composites also display good thermal-oxidative stability, mechanical properties, processability and low costs, which makes it a suitable material for manufacturing aircraft structures. PMR-15 uses the reverse Diels-Alder (RDA) method for crosslinking which provides it with the groundwork for its distinctive thermal stability and a range of 280-300 degree Centigrade use temperature. Regardless of …


An Investigation Of Waste Glass-Based Geopolymers Supplemented With Alumina, Mary U. Christiansen Jan 2013

An Investigation Of Waste Glass-Based Geopolymers Supplemented With Alumina, Mary U. Christiansen

Dissertations, Master's Theses and Master's Reports - Open

An increased consideration of sustainability throughout society has resulted in a surge of research investigating sustainable alternatives to existing construction materials. A new binder system, called a geopolymer, is being investigated to supplement ordinary portland cement (OPC) concrete, which has come under scrutiny because of the CO2 emissions inherent in its production.

Geopolymers are produced from the alkali activation of a powdered aluminosilicate source by an alkaline solution, which results in a dense three-dimensional matrix of tetrahedrally linked aluminosilicates. Geopolymers have shown great potential as a building construction material, offering similar mechanical and durability properties to OPC. Additionally, geopolymers have …


Dysprosium Transport In Nd-Fe-B Pellets, Parawee Pumwongpitak Jan 2013

Dysprosium Transport In Nd-Fe-B Pellets, Parawee Pumwongpitak

Dissertations, Master's Theses and Master's Reports - Open

The addition of heavy rare earth (RE) elements to Nd2Fe14B based magnets to form (Nd,Dy)2Fe14B is known to increase the coercivity and high temperature performance required for hybrid vehicle electric motors and other extreme temperature applications. Attempts to conserve heavy rare earth elements for high temperature (RE)2Fe14B based magnets have led to the development of a grain boundary diffusion process for bulk magnets. This process relies on transport of a heavy rare earth, such as Dy, into a bulk Nd2Fe14B magnet along pores, a low volume fraction of …


Parametric Study Of Reaxff Simulation Parameters For Molecular Dynamics Modeling Of Reactive Carbon Gases, Benjamin David Jensen Jan 2013

Parametric Study Of Reaxff Simulation Parameters For Molecular Dynamics Modeling Of Reactive Carbon Gases, Benjamin David Jensen

Dissertations, Master's Theses and Master's Reports - Open

Abstract

The development of innovative carbon-based materials can be greatly facilitated by molecular modeling techniques. Although the Reax Force Field (ReaxFF) can be used to simulate the chemical behavior of carbon-based systems, the simulation settings required for accurate predictions have not been fully explored. Using the ReaxFF, molecular dynamics (MD) simulations are used to simulate the chemical behavior of pure carbon and hydrocarbon reactive gases that are involved in the formation of carbon structures such as graphite, buckyballs, amorphous carbon, and carbon nanotubes. It is determined that the maximum simulation time step that can be used in MD simulations with …


Intergranular Corrosion And Stress Corrosion Cracking Of Extruded Aa6005a, David James Seguin Jan 2013

Intergranular Corrosion And Stress Corrosion Cracking Of Extruded Aa6005a, David James Seguin

Dissertations, Master's Theses and Master's Reports - Open

A research program focused on understanding the intergranular corrosion (IGC) and stress corrosion cracking (SCC) behavior of AA6005A aluminum extrusions is presented in this dissertation. The relationship between IGC and SCC susceptibility and the mechanisms of SCC in AA6005A extrusions were studied by examining two primary hypotheses.

IGC susceptibility of the elongated grain structure in AA6005A exposed to low pH saltwater was found to depend primarily on the morphology of Cu-containing precipitates adjacent to the grain boundaries in the elongated grain structure. IGC susceptibility was observed when a continuous (or semi-continuous) film of Cu-containing phase was present along the grain …


The Processing Of Aluminum Gasarites Via Thermal Decomposition Of Interstitial Hydrides, Joseph James Licavoli Jan 2013

The Processing Of Aluminum Gasarites Via Thermal Decomposition Of Interstitial Hydrides, Joseph James Licavoli

Dissertations, Master's Theses and Master's Reports - Open

Gasarite structures are a unique type of metallic foam containing tubular pores. The original methods for their production limited them to laboratory study despite appealing foam properties. Thermal decomposition processing of gasarites holds the potential to increase the application of gasarite foams in engineering design by removing several barriers to their industrial scale production. The following study characterized thermal decomposition gasarite processing both experimentally and theoretically. It was found that significant variation was inherent to this process therefore several modifications were necessary to produce gasarites using this method. Conventional means to increase porosity and enhance pore morphology were studied. Pore …


Synthesis Of Graphene And Its Applications For Dye-Sensitized Solar Cells, Hui Wang Jan 2013

Synthesis Of Graphene And Its Applications For Dye-Sensitized Solar Cells, Hui Wang

Dissertations, Master's Theses and Master's Reports - Open

Graphene, which is a two-dimensional carbon material, exhibits unique properties that promise its potential applications in photovoltaic devices. Dye-sensitized solar cell (DSSC) is a representative of the third generation photovoltaic devices. Therefore, it is important to synthesize graphene with special structures, which possess excellent properties for dye-sensitized solar cells.

This dissertation research was focused on (1) the effect of oxygen content on the structure of graphite oxide, (2) the stability of graphene oxide solution, (3) the application of graphene precipitate from graphene oxide solution as counter electrode for DSSCs, (4) the development of a novel synthesis method for the three-dimensional …