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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

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

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

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

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

A Novel Demountable TF Joint Design for Low Aspect Ratio Spherical Torus Tokamaks

Description: A novel shaped design for the radial conductors and demountable electrical joints connecting inner and outer legs of copper TF system conductors in low aspect ratio tokamaks is described and analysis results are presented. Specially shaped designs can optimize profiles of electrical current density, magnetic force, heating, and mechanical stress.
Date: June 11, 2009
Creator: Woolley, Robert D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Lessons Learned During the Manufacture of the NCSX Modular Coils

Description: The National Compact Stellarator Experiment's (NCSX) modular coils presented a number of engineering and manufacturing challenges due to their complex shapes, requirements for high dimensional accuracy and high current density requirements due to space constraints. Being the first of their kind, these coils required the implementation of many new manufacturing and measuring techniques and procedures. This was the first time that these manufacturing techniques and methods were applied in the pro… more
Date: September 15, 2009
Creator: James H. Chrzanowski,Thomas G. Meighan, Steven Raftopoulos and Lawrence Dudek and Paul J. Fogarty
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Long-Term Degradation Testing of High-Temperature Electrolytic Cells

Description: The Idaho National Laboratory (INL) has been researching the application of solid-oxide electrolysis cell for large-scale hydrogen production from steam over a temperature range of 800 to 900ºC. The INL has been testing various solid oxide cell designs to characterize their electrolytic performance operating in the electrolysis mode for hydrogen production. Some results presented in this report were obtained from cells, with an active area of 16 cm2 per cell. The electrolysis cells are electrod… more
Date: August 1, 2009
Creator: Stoots, C.M.; O'Brien, J.E.; Herring, J.S.; Housley, G.K.; Milobar, D.G. & Sohal, M.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analytical Study of Stress State in HTS Solenoids

Description: A main challenge for high field solenoids made of in High Temperature Superconductor (HTS) is the large stress developed in the conductor. This is especially constraining for BSCCO, a brittle and strain sensitive ceramic material. To find parametric correlations useful in magnet design, analytical models can be used. A simple model is herein proposed to obtain the radial, azimuthal and axial stresses in a solenoid as a function of size, i.e. self-field, and of the engineering current density fo… more
Date: January 1, 2009
Creator: Barzi, E. & Terzini, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Novel Demountable TF Joint Design for Low Aspect Ratio Spherical Torus Tokamaks

Description: A novel shaped design for the radial conductors and demountable electrical joints connecting inner and outer legs of copper TF system conductors in low aspect ratio tokamaks is described and analysis results are presented. Specially shaped designs can optimize profiles of electrical current density, magnetic force, heating, and mechanical stress.
Date: May 29, 2009
Creator: Woolley, R.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Insights Gained from Testing Alternate Cell Designs

Description: The Idaho National Laboratory (INL) has been researching the application of solid-oxide electrolysis cell for large-scale hydrogen production from steam over a temperature range of 800 to 900ºC. The INL has been testing various solid oxide cell designs to characterize their electrolytic performance operating in the electrolysis mode for hydrogen production. Some results presented in this report were obtained from cells, initially developed by the Forschungszentrum Jülich and now manufactured by… more
Date: September 1, 2009
Creator: O'Brien, J. E.; Stoots, C. M.; Herring, J. S.; Housley, G. K.; Sohal, M. S.; Milobar, D. G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

System Analyses of High and Low-Temperature Interface Designs for a Nuclear-Driven High-Temperature Electrolysis Hydrogen Production Plant

Description: As part of the Next Generation Nuclear Plant (NGNP) project, an evaluation of a low-temperature heat-pump interface design for a nuclear-driven high-temperature electrolysis (HTE) hydrogen production plant was performed using the UniSim process analysis software. The lowtemperature interface design is intended to reduce the interface temperature between the reactor power conversion system and the hydrogen production plant by extracting process heat from the low temperature portion of the power … more
Date: July 1, 2009
Creator: Harvego, E. A. & O'Brien, J. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EVALUATION OF PROTON-CONDUCTING MEMBRANES FOR USE IN A SULFUR-DIOXIDE DEPOLARIZED ELECTROLYZER

Description: The chemical stability, sulfur dioxide transport, ionic conductivity, and electrolyzer performance have been measured for several commercially available and experimental proton exchange membranes (PEMs) for use in a sulfur dioxide depolarized electrolyzer (SDE). The SDE's function is to produce hydrogen by using the Hybrid Sulfur (HyS) Process, a sulfur based electrochemical/thermochemical hybrid cycle. Membrane stability was evaluated using a screening process where each candidate PEM was heat… more
Date: November 11, 2009
Creator: Hobbs, D.; Elvington, M. & Colon-Mercado, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of Li+ alumino-silicate ion source

Description: To uniformly heat targets to electron-volt temperatures for the study of warm dense matter, one strategy is to deposit most of the ion energy at the peak of energy loss (dE/dx) with a low (E< 5 MeV) kinetic energy beam and a thin target[1]. Lower mass ions have a peak dE/dx at a lower kinetic energy. To this end, a small lithium (Li+) alumino-silicate source has been fabricated, and its emission limit has been measured. These surface ionization sources are heated to 1000-1150 C where they pr… more
Date: April 21, 2009
Creator: Roy, P.K.; Seidl, P.A.; Waldron, W.; Greenway, W.; Lidia, S.; Anders, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

In situ PEM fuel cell water measurements

Description: Efficient PEM (Polymer Electrolyte Membrane) fuel cell performance requires effective water management. To achieve a deeper understanding of water transport and performance issues associated with water management, we have conducted in situ water examinations to help understand the effects of components and operations. High Frequency Resistance (HFR), AC Impedance and Neutron imaging were used to measure water content in operating fuel cells, with various conditions, including current density, r… more
Date: January 1, 2009
Creator: Borup, Rodney L; Mukundan, Rangachary; Davey, John R; Spendelow, Jacob S; Hussey, Daniel S; Jacobson, David L et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Characteristics of Energy Transport of Li-conditioned and non-Li-conditioned Plasmas in the National Spherical Torus Experiment (NSTX)

Description: The transport properties of NSTX plasmas obtained during the 2008 experimental cam- paign have been studied and are reported here. Transport trends and dependences have been isolated, and it is found that both electron and ion energy transport coefficients have strong dependences on local values of nΔT, which in turn is strongly dependent on local current density profile. Without identifying this dependence, it is difficult to identify others, such as the dependence of transport coefficients on… more
Date: October 21, 2009
Creator: S. Ding, S.M. Kaye, R.E. Bell, R. Kaita, H. Kugel, B.P. LeBlanc, S. Paul, B. Wan
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

DARHT 2 kA Cathode Development

Description: In the campaign to achieve 2 kA of electron beam current, we have made several changes to the DARHT-II injector during 2006-2007. These changes resulted in a significant increase in the beam current, achieving the 2 kA milestone. Until recently (before 2007), the maximum beam current that was produced from the 6.5-inch diameter (612M) cathode was about 1300 A when the cathode was operating at a maximum temperature of 1140 C. At this temperature level, the heat loss was dominated by radiation wh… more
Date: March 9, 2009
Creator: Henestroza, E.; Houck, T.; Kwan, J. W.; Leitner, M.; Miram, G.; Prichard, B. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Drift distance survey in DPIS for high current beam production

Description: In a laser ion source, plasma drift distance is one of the most important design parameters. Ion current density and beam pulse width are defined by plasma drift distance between laser target and beam extraction position. In direct plasma injection scheme (DPIS), which uses a laser ion source and Radio Frequency Quadrupole (RFQ) linac, we can apply relatively higher electric field at the beam extraction due to the unique shape of a positively biased electrode. However, when we aim at very high … more
Date: September 20, 2009
Creator: Kanesue,T.; Okamura, M.; Kondo, K.; Tamura, J.; Kashiwagi, H. & Zhang, Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Optimization of interdigitated back contact silicon heterojunction solar cells by two-dimensional numerical simulation

Description: In this paper, two-dimensional (2D) simulation of interdigitated back contact silicon heterojunction (IBC-SHJ) solar cells is presented using Sentaurus Device, a software package of Synopsys TCAD. A model is established incorporating a distribution of trap states of amorphous-silicon material and thermionic emission across the amorphous-silicon / crystalline-silicon heterointerface. The 2D nature of IBC-SHJ device is evaluated and current density-voltage (J-V) curves are generated. Optimization… more
Date: June 9, 2009
Creator: Lu, Meijun; Das, Ujjwal; Bowden, Stuart; Hegedus, Steven & Birmire, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Performance of Single Electrode-Supported Cells Operating in the Electrolysis Mode

Description: An experimental study is under way to assess the performance of electrode-supported solid-oxide cells operating in the steam electrolysis mode for hydrogen production over a temperature range of 800 to 900ºC. Results presented in this paper were obtained from single cells, with an active area of 16 cm2 per cell. The electrolysis cells are electrode-supported, with yttria-stabilized zirconia (YSZ) electrolytes (~10 µm thick), nickel-YSZ steam/hydrogen electrodes (~1400 µm thick), and manganite (… more
Date: November 1, 2009
Creator: O'Brien, J. E.; Housley, G. K. & Milobar, D. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High Performance Electrolyzers for Hybrid Thermochemical Cycles

Description: Extensive electrolyzer testing was performed at the University of South Carolina (USC). Emphasis was given to understanding water transport under various operating (i.e., temperature, membrane pressure differential and current density) and design (i.e., membrane thickness) conditions when it became apparent that water transport plays a deciding role in cell voltage. A mathematical model was developed to further understand the mechanisms of water and SO2 transport, and to predict the effect of o… more
Date: May 10, 2009
Creator: Weidner, Dr. John W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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