Energy Saving Melting and Revert Reduction Technology (Energy-SMARRT): Surface/Near Surface Indication - Characterization of Surface Anomalies from Magnetic Particle and Liquid Penetrant Indications (open access)

Energy Saving Melting and Revert Reduction Technology (Energy-SMARRT): Surface/Near Surface Indication - Characterization of Surface Anomalies from Magnetic Particle and Liquid Penetrant Indications

The systematic study and characterization of surface indications has never been conducted. Producers and users of castings do not have any data on which they can reliably communicate the nature of these indications or their effect on the performance of parts. Clearly, the ultimate intent of any work in this area is to eliminate indications that do in fact degrade properties. However, it may be impractical physically and/or financially to eliminate all surface imperfections. This project focused on the ones that actually degrade properties. The initial work was to identify those that degrade properties. Accurate numerical simulations of casting service performance allow designers to use the geometric flexibility of castings and the superior properties of steel to produce lighter weight and more energy efficient components for transportation systems (cars and trucks), construction, and mining. Accurate simulations increase the net melting energy efficiency by improving casting yield and reducing rework and scrap. Conservatively assuming a 10% improvement in yield, approximately 1.33 x 1012 BTU/year can be saved with this technology. In addition, CO2 emissions will be reduced by approximately 117,050 tons per year.
Date: February 20, 2014
Creator: Griffin, John
System: The UNT Digital Library
241-AY-102 Leak Detection Pit Drain Line Inspection Report (open access)

241-AY-102 Leak Detection Pit Drain Line Inspection Report

This document provides a description of the design components, operational approach, and results from the Tank AY-102 leak detection pit drain piping visual inspection. To perform this inspection a custom robotic crawler with a deployment device was designed, built, and operated by IHI Southwest Technologies, Inc. for WRPS to inspect the 6-inch leak detection pit drain line.
Date: January 20, 2014
Creator: Boomer, Kayle D.; Engeman, Jason K.; Gunter, Jason R.; Joslyn, Cameron C.; Vazquez, Brandon J.; Venetz, Theodore J. et al.
System: The UNT Digital Library
Atomic-Scale Chemical, Physical and Electronic Properties of the Subsurface Hydride of Palladium (open access)

Atomic-Scale Chemical, Physical and Electronic Properties of the Subsurface Hydride of Palladium

We employed low-temperature, extreme-high vacuum scanning tunneling microscopy (STM) to investigate the roles of subsurface hydride (H) and deuteride (D) in the surface reconstruction and surface reactivity of Pd{110}. Specifically, we gained the ability to tailor the surface structure of Pd{110} both by preparation method and by deposition of deuterium from the gas phase. We observed thiophene at low coverage on Pd{110} to determine its adsorption orientation and electronic structure through scanning tunneling spectroscopy (STS) – namely, conductance spectroscopy and differential conductance imaging. We developed the methods necessary to coadsorb D adatoms with thiophene molecules, and to induce the reaction of individual molecules with predefined subsurface H or D features. In the case of Pd{110}, we found a much more pronounced effect from subsurface D, as it is influenced by the surface directionality. These experiments facilitate an understanding of the role of surface and subsurface H and D in heterogeneous catalytic processes, specifically in the hydrodesulfuization (HDS) of thiophene, an important and ubiquitous component found to be detrimental to petroleum refining.
Date: January 20, 2014
Creator: Weiss, Paul
System: The UNT Digital Library
Local Optical Spectroscopies for Subnanometer Spatial Resolution Chemical Imaging (open access)

Local Optical Spectroscopies for Subnanometer Spatial Resolution Chemical Imaging

The evanescently coupled photon scanning tunneling microscopes (STMs) have special requirements in terms of stability and optical access. We have made substantial improvements to the stability, resolution, and noise floor of our custom-built visible-photon STM, and will translate these advances to our infrared instrument. Double vibration isolation of the STM base with a damping system achieved increased rigidity, giving high tunneling junction stability for long-duration and high-power illumination. Light frequency modulation with an optical chopper and phase-sensitive detection now enhance the signal-to-noise ratio of the tunneling junction during irradiation.
Date: January 20, 2014
Creator: Weiss, Paul
System: The UNT Digital Library
Noble Gas Concept Of Operation (open access)

Noble Gas Concept Of Operation

None
Date: January 20, 2014
Creator: Carrigan, C R
System: The UNT Digital Library
Strategies for Probing Nanometer-Scale Electrocatalysts: From Single Particles to Catalyst-Membrane Architectures (open access)

Strategies for Probing Nanometer-Scale Electrocatalysts: From Single Particles to Catalyst-Membrane Architectures

The project primary objectives are to prepare and elucidate the promoting properties of materials that possess high activity for the conversion of hydrogen and related small molecules (water, oxygen, carbon monoxide and methanol) in polymer electrolyte fuel cells. One area of research has focused on the study of catalyst materials. Protocols were developed for probing the structure and benchmarking the activity of Pt and Pt bimetallic nanometer-scale catalyst against Pt single crystal electrode standards. A second area has targeted fuel cell membrane and the advancement of simple methods mainly based on vibrational spectroscopy that can be applied broadly in the study of membrane structure and transport properties. Infrared and Raman methods combined with least-squares data modeling were applied to investigate and assist the design of robust, proton conductive membranes, which resist reactant crossover.
Date: January 20, 2014
Creator: Korzeniewski, Carol
System: The UNT Digital Library