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DOE Award No. DE-FC36-03GO13108 Novel Non-Precious Metal Catalysts for PEMFC: Catalyst Selection Through Molecular Modeling and Durability Studies Final Report (September 2003 – October 2008)

Description: The objective of this project is to develop novel non-precious metal electrocatalysts for oxygen reduction reaction (ORR), and demonstrate the potential of the catalysts to perform at least as good as conventional Pt catalysts currently in use in polymer electrolyte membrane fuel cell (PEMFC) with a cost at least 50 % less than a target of 0.2 g (Pt loading)/peak kW and with durability > 2,000 h operation with less than 10 % power degradation. A novel nitrogen-modified carbon-based catalyst was… more
Date: March 3, 2009
Creator: Popov, Branko N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Electrochemical arsenic remediation for rural Bangladesh

Description: Arsenic in drinking water is a major public health problem threatening the lives of over 140 million people worldwide. In Bangladesh alone, up to 57 million people drink arsenic-laden water from shallow wells. ElectroChemical Arsenic Remediation(ECAR) overcomes many of the obstacles that plague current technologies and can be used affordably and on a small-scale, allowing for rapid dissemination into Bangladesh to address this arsenic crisis. In this work, ECAR was shown to effectively reduce 5… more
Date: January 1, 2009
Creator: Addy, Susan Amrose
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Scalable Methods for Electronic Excitations and Optical Responses of Nanstructures: Mathematics to Algorithms to Observables

Description: This multi-investigator project was concerned with the development and application of new methods and computer codes that would allow realistic modeling of nanosystems. Carter's part in this team effort involved two method/algorithm/code development projects during the first 14 months of this grant. Carter's group has been advancing theory and applications of the orbital-free density functional theory (OF-DFT), the only DFT method that exhibits linear scaling for metals. Such a method offers th… more
Date: January 23, 2009
Creator: Carter, Emily A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

DOE Award No. DE-FC36-03GO13108 Novel Non-Precious Metal Catalysts for PEMFC: Catalyst Selection Through Molecular Modeling and Durability Studies Final Report (September 2003 – October 2008)

Description: The objective of this project is to develop novel non-precious metal electrocatalysts for oxygen reduction reaction (ORR), and demonstrate the potential of the catalysts to perform at least as good as conventional Pt catalysts currently in use in polymer electrolyte membrane fuel cell (PEMFC) with a cost at least 50 % less than a target of 0.2 g (Pt loading)/peak kW and with durability > 2,000 h operation with less than 10 % power degradation. A novel nitrogen-modified carbon-based catalyst was… more
Date: February 20, 2009
Creator: Popov, Branko N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

HANFORD DOUBLE SHELL TANK THERMAL AND SEISMIC PROJECT SUMMARY OF COMBINED THERMAL AND OPERATING LOADS WITH SEISMIC ANALYSIS

Description: This report summarizes the results of the Double-Shell Tank Thermal and Operating Loads Analysis (TaLA) combined with the Seismic Analysis. This combined analysis provides a thorough, defensible, and documented analysis that will become a part of the overall analysis of record for the Hanford double-shell tanks (DSTs). The bases of the analytical work presented herein are two ANSYS{reg_sign} finite element models that were developed to represent a bounding-case tank. The TaLA model includes the… more
Date: January 15, 2009
Creator: TC, MACKEY; JE, DEIBLER; MW, RINKER; KI, JOHNSON; FG, ABATT; NK, KARRI et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of pseudo-random binary gratings and arrays for calibration of surface profile metrology tools

Description: Optical Metrology tools, especially for short wavelength (EUV and X-Ray), must cover a wide range of spatial frequencies from the very low, which affects figure, to the important mid-spatial frequencies and the high spatial frequency range, which produces undesirable flair. A major difficulty in using surface profilometers arises due to the unknown Modulation Transfer Function (MTF) of the instruments. Therefore, accurate calibration of profilometers, the understanding of their MTF limitations,… more
Date: January 16, 2009
Creator: Barber, Samuel K.; Soldate, Paul; Anderson, Erik; Cambie, Rosanna; McKinney, Wayne R.; Takacs, Peter Z. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Comparative Analysis of Natural Convection Flows Simulated by both the Conservation and Incompressible Forms of the Navier-Stokes Equations in a Differentially-Heated Square Cavity

Description: This report illustrates a comparative study to analyze the physical differences between numerical simulations obtained with both the conservation and incompressible forms of the Navier-Stokes equations for natural convection flows in simple geometries. The purpose of this study is to quantify how the incompressible flow assumption (which is based upon constant density advection, divergence-free flow, and the Boussinesq gravitational body force approximation) differs from the conservation form (… more
Date: January 1, 2009
Creator: Martineau, Richard C.; Berry, Ray A.; Esteve, Aurélia; Hamman, Kurt D.; Knoll, Dana A.; Park, Ryosuke et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of multi-layer thin films for energy storage.

Description: We investigate here the feasibility of increasing the energy density of thin-film capacitors by construction of a multi-layer capacitor device through ablation and redeposition of the capacitor materials using a high-power pulsed ion beam. The deposition experiments were conducted on the RHEPP-1 facility at Sandia National Laboratories. The dielectric capacitor filler material was a composition of Lead-Lanthanum-Zirconium-Titanium oxide (PLZT). The energy storage can be increased by using mater… more
Date: January 1, 2009
Creator: Renk, Timothy Jerome & Monson, Todd
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Research and Development of a New Field Enhanced Low Temperature Thermionic Cathode that Enables Fluorescent Dimming and Loan Shedding without Auxiliary Cathode Heating

Description: This is the final report for project entitled 'Research and development of a new field enhanced low temperature thermionic cathode that enables fluorescent dimming and load shedding without auxiliary cathode heating', under Agreement Number: DE-FC26-04NT-42329. Under this project, a highly efficient CNT based thermionic cathode was demonstrated. This cathode is capable of emitting electron at a current density two order of magnitude stronger then a typical fluorescent cathode at same temperatur… more
Date: January 7, 2009
Creator: Jin, Feng
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Simulation of Electron Cloud Density Distributions in RHIC Dipoles at Injection and Transition and Estimates for Scrubbing Times

Description: In this report we summarize electron-cloud simulations for the RHIC dipole regions at injection and transition to estimate if scrubbing over practical time scales at injection would reduce the electron cloud density at transition to significantly lower values. The lower electron cloud density at transition will allow for an increase in the ion intensity.
Date: January 2, 2009
Creator: He, P.; Blaskiewicz, M. & Fischer, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Systematic Approaches to Predictive Computational Chemistry using the Correlation Consistent Basis Sets

Description: The development of the correlation consistent basis sets, cc-pVnZ (where n = D, T, Q, etc.) have allowed for the systematic elucidation of the intrinsic accuracy of ab initio quantum chemical methods. In density functional theory (DFT), where the cc-pVnZ basis sets are not necessarily optimal in their current form, the elucidation of the intrinsic accuracy of DFT methods cannot always be accomplished. This dissertation outlines investigations into the basis set requirements for DFT and how the … more
Date: May 2009
Creator: Prascher, Brian P.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Cavity Light-Emitting Diode for Durable, High-Brightness and High-Efficiency Lighting Applications: First Budget Period Technical Report

Description: A COLED device consists of a top electrode (anode) and a bottom electrode (cathode) separated by a thin dielectric layer. In this metal/dielectric stack, numerous small wells, or cavities, are etched through the top electrode and the dielectric layer. These cavities are subsequently filled with LEP molecules. When a voltage is applied between the top and bottom electrodes, holes (from the top electrode) and electrons (from the bottom electrode) are injected into the polymer. Light emission is g… more
Date: September 30, 2009
Creator: Shi, Yijian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A WEAR MODEL FOR DIESEL ENGINE EXHAUST VALVES

Description: The work summarized here comprises the concluding effort of a multi-year project, funded by the U.S. Department of Energy, Office of Vehicle Technologies. It supports the development of a better understanding of advanced diesel engine designs in which enhanced power density, energy efficiency, and emissions control place increasing demands upon the durability of engine materials. Many kinds of metallic alloys are used in engines depending on the operating stresses, temperatures, and chemical en… more
Date: November 1, 2009
Creator: Blau, Peter Julian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Simulations of Electron-Cloud Current Density Measurements in Dipoles, Drifts And Wigglers at CesrTA

Description: A core component of the CesrTA research program at Cornell is to fully understand the electron cloud effect through the use of simulation programs that have been developed to predict the growth of the cloud and its interaction with the beam. As a local probe of the electron cloud, several segmented retarding field analyzers (RFAs) have been installed in CesrTA in dipole, drift and wiggler regions. Using these RFAs, the energy spectrum of the time-average electron cloud current density striking … more
Date: May 4, 2009
Creator: Calvey, J.; Crittenden, J. A.; Dugan, G.; Greenwald, S.; Livezey, J. A.; Palmer, M. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Effects of Fire on the Function of the 200-BP-1 Engineered Surface Barrier

Description: A critical unknown in use of barrier technology for long-term waste isolation is performance after a major disturbance especially when institutional controls are intact, but there are no resources to implement corrective actions. The objective of this study was to quantify the effects of wild fire on alterations the function of an engineered barrier. A controlled burn September 26, 2008 was used to remove all the vegetation from the north side of the barrier. Flame heights exceeded 9 m and temp… more
Date: September 1, 2009
Creator: Ward, Anderson L.; Link, Steven O.; Hasan, Nazmul & Draper, Kathryn E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Observation of relativistic effects in collective Thomson scattering

Description: We observe relativistic modifications to the Thomson scattering spectrum in a traditionally classical regime: v{sub osc}/c = eE{sub 0}/cm{omega}{sub 0} << 1 and T{sub e} < 1 keV. The modifications result from scattering off electron-plasma fluctuations with relativistic phase velocities. Normalized phase velocities v/c between 0.03 and 0.12 have been achieved in a N{sub 2} gas-jet plasma by varying the plasma density from 3 x 10{sup 18} cm{sup -3} to 7 x 10{sup 19} cm{sup -3} and elect… more
Date: October 8, 2009
Creator: Ross, J S; Glenzer, S H; Palastro, J P; Pollock, B B; Price, D; Divol, L et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Nuclear Lattice Calculation

Description: Thermal property of low-density neutron matter is reliably determined by a large scale computation using supercomputers. Physics of superfluid in neutron matter are clarified, as a basis of the structure of neutron-halo nuclei and of outer crust of neutron stars. In achieving these, a novel method of lattice quantum Monte Carlo technique is applied by combining with effective field theory.
Date: June 30, 2009
Creator: Seki, Ryoichi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance Evaluation for Modular, Scalable Overhead Cooling Systems In Data Centers

Description: Scientific and enterprise data centers, IT equipment product development, and research data center laboratories typically require continuous cooling to control inlet air temperatures within recommended operating levels for the IT equipment. The consolidation and higher density aggregation of slim computing, storage and networking hardware has resulted in higher power density than what the raised-floor system design, coupled with commonly used computer rack air conditioning (CRAC) units, was ori… more
Date: May 1, 2009
Creator: Xu, TengFang T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of High-Te Plasmas Heated by HHFW in NSTX

Description: The implementation in TRANSP of a recent version of TORIC capable of calculating power deposition for HHFW conditions is used to analyze NSTX plasma under different operating conditions. The power deposition profile into the electrons is obtained for high-Te conditions - Te ≤ 5keV - obtained in He and D plasmas with ITB. HHFW heating of NBI-induced H-mode plasmas is discussed. At the RF onset the RF power is divided evenly between the electrons and the fast particles, but as the latter thermali… more
Date: June 26, 2009
Creator: LeBlanc, P.; Bell, R. E.; Bonoli, P.; Hosea, J. C.; Mazzucato, E.; Phillips, C. K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Lower Hybrid Heating and Current Drive on the Alcator C-Mod Tokamak

Description: On the Alcator C-Mod tokamak, lower hybrid current drive (LHCD) is being used to modify the current profile with the aim of obtaining advanced tokamak (AT) performance in plasmas with parameters similar to those that would be required on ITER. To date, power levels in excess of 1 MW at a frequency of 4.6 GHz have been coupled into a variety of plasmas. Experiments have established that LHCD on C-Mod behaves globally as predicted by theory. Bulk current drive efficiencies, n20IlhR/Plh ~ 0.25, in… more
Date: November 20, 2009
Creator: R. Wilson, R. Parker, M. Bitter, P.T. Bonoli, C. Fiore, R.W. Harvey, K. Hill, A.E. Hubbard, J.W. Hughes, A. Ince-Cushman, C. Kessel, J.S. Ko, O. Meneghini, C.K. Phillips, M. Porkolab, J. Rice, A.E. Schmidt, S. Scott,S. Shiraiwa, E. Valeo, G.Wallace, J.C. Wright and the Alcator C-Mod Team
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interpretation of Wild 2 Dust Fine Structure: Comparison of Stardust Aluminium Foil Craters to the Three-Dimensional Shape of Experimental Impacts by Artificial Aggregate Particles and Meteorite Powders

Description: New experimental results show that Stardust crater morphology is consistent with interpretation of many larger Wild 2 dust grains being aggregates, albeit most of low porosity and therefore relatively high density. The majority of large Stardust grains (i.e. those carrying most of the cometary dust mass) probably had density of 2.4 g cm{sup -3} (similar to soda-lime glass used in earlier calibration experiments) or greater, and porosity of 25% or less, akin to consolidated carbonaceous chondrit… more
Date: December 10, 2009
Creator: Kearsley, A T; Burchell, M J; Price, M C; Graham, G A; Wozniakiewicz, P J; Cole, M J et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Performance Evaluation for Modular, Scalable Cooling Systems with Hot Aisle Containment in Data Centers

Description: Scientific and enterprise data centers, IT equipment product development, and research data center laboratories typically require continuous cooling to control inlet air temperatures within recommended operating levels for the IT equipment. The consolidation and higher density aggregation of slim computing, storage and networking hardware has resulted in higher power density than what the raised-floor system design, coupled with commonly used computer rack air conditioning (CRAC) units, was ori… more
Date: May 1, 2009
Creator: Adams, Barbara J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Statistics of particle concentration in free-surface turbulence

Description: Particles on the surface of an incompressible fluid maintained in a turbulent steady-state cluster into spatio-temporally complex flow structures. We experimentally study the statistics of particle concentration n(r, t) over various coarse-grained scales r' in the inertial range. Another control parameter is the Taylor Microscale Reynolds number Re{sub {lambda}}. The focus is on the steady state probability density function {Pi}(n{sub r}). Attention is also given to the variance {sigma}{sup 2}(… more
Date: January 1, 2009
Creator: Bandi, Mahesh M; Larkin, J & Goldburg, W
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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