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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) (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)

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 obtained by modifying carbon black with nitrogen-containing organic precursor in the absence of transition metal precursor. The catalyst shows the onset potential of approximately 0.76 V (NHE) for ORR and the amount of H2O2 of approximately 3% at 0.5 V (NHE). Furthermore, a carbon composite catalyst was achieved through the high-temperature pyrolysis of the precursors of transition metal (Co and Fe) and nitrogen supported on the nitrogen-modified carbon-based catalyst, followed by chemical post-treatment. This catalyst showed an onset potential for ORR as high as 0.87 V (NHE), and generated less than 1 % of H2O2. The PEM fuel cell exhibited a current density of 2.3 A cm-2 at 0.2 V for a catalyst loading of 6.0 mg cm-2. No …
Date: March 3, 2009
Creator: Popov, Branko N.
System: The UNT Digital Library
Energy Provisions in the American Recovery and Reinvestment Act of 2009 (P.L. 111-5) (open access)

Energy Provisions in the American Recovery and Reinvestment Act of 2009 (P.L. 111-5)

This report discusses the energy appropriations in the American Recovery and Reinvestment Act of 2009 (ARRA, P.L. 111-5). It includes background information, a summary of provisions, and detailed explanations of the relevant appropriations and tax provisions.
Date: March 3, 2009
Creator: Sissine, Fred; Andrews, Anthony; Folger, Peter; Kaplan, Stan M.; Morgan, Daniel; Stine, Deborah D. et al.
System: The UNT Digital Library
Feasibility Analysis For Heating Tribal Buildings with Biomass (open access)

Feasibility Analysis For Heating Tribal Buildings with Biomass

This report provides a feasibility study for the heating of Tribal buildings using woody biomass. The study was conducted for the Confederated Salish and Kootenai Tribes of the Flathead Reservation in western Montana. S&K Holding Company and TP Roche Company completed the study and worked together to provide the final report. This project was funded by the DOE's Tribal Energy Program.
Date: March 3, 2009
Creator: Clairmont, Steve; Bourdon, Micky; Roche, Tom & Frye, Colene
System: The UNT Digital Library
A Low-Cost Soft-Switched DC/DC Converter for Solid-Oxide Fuel Cells (open access)

A Low-Cost Soft-Switched DC/DC Converter for Solid-Oxide Fuel Cells

A highly efficient DC to DC converter has been developed for low-voltage high-current solid oxide fuel cells. The newly developed 'V6' converter resembles what has been done in internal combustion engine that split into multiple cylinders to increase the output capacity without having to increase individual cell size and to smooth out the torque with interleaving operation. The development was started with topology overview to ensure that all the DC to DC converter circuits were included in the study. Efficiency models for different circuit topologies were established, and computer simulations were performed to determine the best candidate converter circuit. Through design optimization including topology selection, device selection, magnetic component design, thermal design, and digital controller design, a bench prototype rated 5-kW, with 20 to 50V input and 200/400V output was fabricated and tested. Efficiency goal of 97% was proven achievable through hardware experiment. This DC to DC converter was then modified in the later stage to converter 35 to 63 V input and 13.8 V output for automotive charging applications. The complete prototype was tested at Delphi with their solid oxide fuel cell test stand to verify the performance of the modified DC to DC converter. The output was tested …
Date: March 3, 2009
Creator: Lai, Jason
System: The UNT Digital Library
Medicare Advantage (open access)

Medicare Advantage

This report is an overview of the Medicare Advantage (MA) program, an alternative way for Medicare beneficiaries to receive covered benefits, and includes legislative history and analysis of recent trends.
Date: March 3, 2009
Creator: Morgan, Paulette C.
System: The UNT Digital Library
Optimal explicit strong-stability-preserving general linear methods : complete results. (open access)

Optimal explicit strong-stability-preserving general linear methods : complete results.

This paper constructs strong-stability-preserving general linear time-stepping methods that are well suited for hyperbolic PDEs discretized by the method of lines. These methods generalize both Runge-Kutta (RK) and linear multistep schemes. They have high stage orders and hence are less susceptible than RK methods to order reduction from source terms or nonhomogeneous boundary conditions. A global optimization strategy is used to find the most efficient schemes that have low storage requirements. Numerical results illustrate the theoretical findings.
Date: March 3, 2009
Creator: Constantinescu, E. M.; Sandu, A.; Science, Mathematics and Computer & Univ., Virginia Polytechnic Inst. and State
System: The UNT Digital Library
Russia-Georgia Conflict in August 2008: Context and Implications for U.S. Interests (open access)

Russia-Georgia Conflict in August 2008: Context and Implications for U.S. Interests

This report provides background information and recent developments in Russia-Georgia conflict in South Ossetia. The report discusses renewed conflict in South Ossetia, implications for Georgia and Russia, and international and U.S. responses.
Date: March 3, 2009
Creator: Nichol, Jim
System: The UNT Digital Library
Securing General Aviation (open access)

Securing General Aviation

This report discusses safety concerns regarding General aviation (GA), which encompasses a wide range of airports, aircraft, and flight operations. Because GA plays a small but important role in the U.S. economy, improving upon GA security without unduly impeding air commerce or limiting the freedom of movement by air remains a significant challenge.
Date: March 3, 2009
Creator: Elias, Bart
System: The UNT Digital Library
SQA(TM): Surface Quality Assured Steel Bar Program (open access)

SQA(TM): Surface Quality Assured Steel Bar Program

OG Technologies, Inc. (OGT) has led this SQA (Surface Quality Assured Steel Bar) program to solve the major surface quality problems plaguing the US special quality steel bars and rods industry and their customers, based on crosscutting sensors and controls technologies. Surface defects in steel formed in a hot rolling process are one of the most common quality issues faced by the American steel industry, accounting for roughly 50% of the rejects or 2.5% of the total shipment. Unlike other problems such as the mechanical properties of the steel product, most surface defects are sporadic and cannot be addressed based on sampling techniques. This issue hurts the rolling industry and their customers in their process efficiency and operational costs. The goal of this program is to develop and demonstrate an SQA prototype, with synergy of HotEye® and other innovations, that enables effective rolling process control and efficient quality control. HotEye®, OGT’s invention, delivers high definition images of workpieces at or exceeding 1,450C while the workpieces travel at 100 m/s. The elimination of surface defect rejects will be achieved through the integration of imaging-based quality assessment, advanced signal processing, predictive process controls and the integration with other quality control tools. The …
Date: March 3, 2009
Creator: Chang, Tzyy-Shuh; Shi, Jianjun & Zhou, Shiyu
System: The UNT Digital Library
TIME-TEMPERATURE-TRANSFORMATION DIAGRAMS FOR THE SLUDGE BATCH 3 - FRIT 418 GLASS SYSTEM (open access)

TIME-TEMPERATURE-TRANSFORMATION DIAGRAMS FOR THE SLUDGE BATCH 3 - FRIT 418 GLASS SYSTEM

As a part of the Waste Acceptance Product Specifications (WAPS) for Vitrified High-Level Waste Forms defined by the Department of Energy - Office of Environmental Management, the phase stability must be determined for each of the projected high-level waste (HLW) types at the Savannah River Site (SRS). Specifically, WAPS 1.4.1 requires the glass transition temperature (Tg) to be defined and time-temperature-transformation (TTT) diagrams to be developed. The Tg of a glass is an indicator of the approximate temperature where the supercooled liquid converts to a solid on cooling or conversely, where the solid begins to behave as a viscoelastic solid on heating. A TTT diagram identifies the crystalline phases that can form as a function of time and temperature for a given waste type or more specifically, the borosilicate glass waste form. In order to assess durability, the Product Consistency Test (PCT) was used and the durability results compared to the Environmental Assessment (EA) glass. The measurement of glass transition temperature and the development of TTT diagrams have already been performed for the seven Defense Waste Processing Facility (DWPF) projected compositions as defined in the Waste Form Compliance Plan (WCP). These measurements were performed before DWPF start-up and the results …
Date: March 3, 2009
Creator: Billings, A & Tommy Edwards, T
System: The UNT Digital Library
Up-Scaling Geochemical Reaction Rates for Carbon Dioxide (CO2) in Deep Saline Aquifers (open access)

Up-Scaling Geochemical Reaction Rates for Carbon Dioxide (CO2) in Deep Saline Aquifers

The overall goal of the project was to bridge the gap between our knowledge of small-scale geochemical reaction rates and reaction rates meaningful for modeling transport at core scales. The working hypothesis was that reaction rates, determined from laboratory measurements based upon reactions typically conducted in well mixed batch reactors using pulverized reactive media may be significantly changed in in situ porous media flow due to rock microstructure heterogeneity. Specifically we hypothesized that, generally, reactive mineral surfaces are not uniformly accessible to reactive fluids due to the random deposition of mineral grains and to the variation in flow rates within a pore network. Expected bulk reaction rates would therefore have to be correctly up-scaled to reflect such heterogeneity. The specific objective was to develop a computational tool that integrates existing measurement capabilities with pore-scale network models of fluid flow and reactive transport. The existing measurement capabilities to be integrated consisted of (a) pore space morphology, (b) rock mineralogy, and (c) geochemical reaction rates. The objective was accomplished by: (1) characterizing sedimentary sandstone rock morphology using X-ray computed microtomography, (2) mapping rock mineralogy using back-scattered electron microscopy (BSE), X-ray dispersive spectroscopy (EDX) and CMT, (3) characterizing pore-accessible reactive mineral surface area, …
Date: March 3, 2009
Creator: Lindquist, W Brent
System: The UNT Digital Library
The Use of Haz-Flote to Efficiently Remove Mercury from Contaminated Materials (open access)

The Use of Haz-Flote to Efficiently Remove Mercury from Contaminated Materials

There are thousands of known contaminated sites in the United Stated, including Superfund sites (1500 to 2100 sites), RCRA corrective action sites (1500 to 3500 sites), underground storage tanks (295,000 sites), U.S. Department of Defense sites (7300 sites), U.S. Department of Energy sites (4,000 sites), mining refuse piles, and numerous other hazardous metals and organic contamination sites. Only a small percentage of these sites has been cleaned up. The development of innovative technologies to handle the various clean-up problems on a national and international scale is commonplace. Many innovative technologies have been developed that can be used to effectively remediate contaminated materials. Unfortunately, many of these technologies are only effective for materials coarser than approximately 200 mesh. In addition, these technologies usually require considerable investment in equipment, and the clean-up costs of soil material are relatively high - in excess of $100 to $500 per yd{sup 3}. These costs result from the elaborate nature of the processes, the costs for power, and the chemical cost. The fine materials are disposed of or treated at considerable costs. As a result, the costs often associated with amelioration of contaminated sites are high. Western Research institute is in the process of developing an …
Date: March 3, 2009
Creator: Brown, Terry
System: The UNT Digital Library
The Department of the Treasury’s Authority to Regulate GSE Debt: A Legal Analysis (open access)

The Department of the Treasury’s Authority to Regulate GSE Debt: A Legal Analysis

This report analyzes the Department of the Treasury's legal authority over Fannie Mae and Freddie Mac and concludes that a court would likely hold that the department possesses the power to regulate the amount of debt issued by these two organizations.
Date: March 3, 2008
Creator: Seitzinger, Michael V.
System: The UNT Digital Library
The Design, Construction, and Operation of Long-Distance High-Voltage Electricity Transmission Technologies. (open access)

The Design, Construction, and Operation of Long-Distance High-Voltage Electricity Transmission Technologies.

This report focuses on transmission lines, which operate at voltages of 115 kV and higher. Currently, the highest voltage lines comprising the North American power grid are at 765 kV. The grid is the network of transmission lines that interconnect most large power plants on the North American continent. One transmission line at this high voltage was built near Chicago as part of the interconnection for three large nuclear power plants southwest of the city. Lines at this voltage also serve markets in New York and New England, also very high demand regions. The large power transfers along the West Coast are generally at 230 or 500 kV. Just as there are practical limits to centralization of power production, there are practical limits to increasing line voltage. As voltage increases, the height of the supporting towers, the size of the insulators, the distance between conductors on a tower, and even the width of the right-of-way (ROW) required increase. These design features safely isolate the electric power, which has an increasing tendency to arc to ground as the voltage (or electrical potential) increases. In addition, very high voltages (345 kV and above) are subject to corona losses. These losses are a …
Date: March 3, 2008
Creator: Molburg, J. C.; Kavicky, J. A. & Picel, K. C.
System: The UNT Digital Library
Development and Testing of a Life Cycle Model and a Parameterization of Thin Mid-level Stratiform Clouds (open access)

Development and Testing of a Life Cycle Model and a Parameterization of Thin Mid-level Stratiform Clouds

We used a cloud-resolving model (a detailed computer model of cloud systems) to evaluate and improve the representation of clouds in global atmospheric models used for numerical weather prediction and climate modeling. We also used observations of the atmospheric state, including clouds, made at DOE's Atmospheric Radiation Measurement (ARM) Program's Climate Research Facility located in the Southern Great Plains (Kansas and Oklahoma) during Intensive Observation Periods to evaluate our detailed computer model as well as a single-column version of a global atmospheric model used for numerical weather prediction (the Global Forecast System of the NOAA National Centers for Environmental Prediction). This so-called Single-Column Modeling approach has proved to be a very effective method for testing the representation of clouds in global atmospheric models. The method relies on detailed observations of the atmospheric state, including clouds, in an atmospheric column comparable in size to a grid column used in a global atmospheric model. The required observations are made by a combination of in situ and remote sensing instruments. One of the greatest problems facing mankind at the present is climate change. Part of the problem is our limited ability to predict the regional patterns of climate change. In order to increase …
Date: March 3, 2008
Creator: Krueger, Steven K.
System: The UNT Digital Library
International Illegal Trade in Wildlife: Threats and U.S. Policy (open access)

International Illegal Trade in Wildlife: Threats and U.S. Policy

This report focuses on the international trade in terrestrial fauna, largely excluding trade in illegal plants, including timber, and fish.
Date: March 3, 2008
Creator: Wyler, Liana S. & Sheikh, Pervaze A.
System: The UNT Digital Library
A Multi-Layered Ceramic Composite for Impermeable Fuel Cladding for COmmercial Wate Reactors (open access)

A Multi-Layered Ceramic Composite for Impermeable Fuel Cladding for COmmercial Wate Reactors

A triplex nuclear fuel cladding is developed to further improve the passive safety of commercial nuclear plants, to increase the burnup and durablity of nuclear fuel, to improve the power density and economics of nuclear power, and to reduce the amount of spent fuel requiring disposal or recycle.
Date: March 3, 2008
Creator: Feinroth, Herbert
System: The UNT Digital Library
Navy Role in Global War on Terrorism (GWOT) — Background and Issues for Congress (open access)

Navy Role in Global War on Terrorism (GWOT) — Background and Issues for Congress

None
Date: March 3, 2008
Creator: unknown
System: The UNT Digital Library
New Markets Tax Credit: An Introduction (open access)

New Markets Tax Credit: An Introduction

None
Date: March 3, 2008
Creator: unknown
System: The UNT Digital Library
On the Long-Term Average Cost of CO2 Transport and Storage (open access)

On the Long-Term Average Cost of CO2 Transport and Storage

Paper describes general trends in the cost of CO2 transport and storage (including measurement, monitoring, and verification) and how these can be used to justify a proxy cost to cover a large number of potential CCS commercial deployment scenarios.
Date: March 3, 2008
Creator: Dooley, James J.; Dahowski, Robert T. & Davidson, Casie L.
System: The UNT Digital Library
Predictions of H-mode performance in ITER (open access)

Predictions of H-mode performance in ITER

Time-dependent integrated predictive modeling is carried out using the PTRANSP code to predict fusion power and parameters such as alpha particle density and pressure in ITER H-mode plasmas. Auxiliary heating by negative ion neutral beam injection and ion cyclotron heating of He3 minority ions are modeled, and the GLF23 transport model is used in the prediction of the evolution of plasma temperature profiles. Effects of beam steering, beam torque, plasma rotation, beam current drive, pedestal temperatures, sawtooth oscillations, magnetic diffusion, and accumulation of He ash are treated self-consistently. Variations in assumptions associated with physics uncertainties for standard base-line DT H-mode plasmas (with Ip=15 MA, BTF=5.3 T, and Greenwald fraction=0.86) lead to a range of predictions for DT fusion power PDT and quasi-steady state fusion QDT (≡ PDT/Paux). Typical predictions assuming Paux = 50-53 MW yield PDT = 250- 720 MW and QDT = 5 - 14. In some cases where Paux is ramped down or shut off after initial flat-top conditions, quasi-steady QDT can be considerably higher, even infinite. Adverse physics assumptions such as existence of an inward pinch of the helium ash and an ash recycling coefficient approaching unity lead to very low values for PDT. Alternative scenarios with …
Date: March 3, 2008
Creator: R.V. Budny, R.Andre, G.Bateman, F.Halpern, C.E.Kessel, A.Kritz, and D.McCune
System: The UNT Digital Library
Pulse Jet Mixer Overblow Testing for Assessment of Loadings During Multiple Overblows (open access)

Pulse Jet Mixer Overblow Testing for Assessment of Loadings During Multiple Overblows

The U.S. Department of Energy (DOE) Office of River Protection’s Waste Treatment Plant (WTP) is being designed and built to pretreat and then vitrify a large portion of the wastes in Hanford’s 177 underground waste storage tanks. The WTP consists of three primary facilities: pretreatment, low-activity waste (LAW) vitrification, and high-level waste (HLW) vitrification. The pretreatment facility will receive waste feed from the Hanford tank farms and separate it into 1) a high-volume, low-activity liquid stream stripped of most solids and radionuclides and 2) a much smaller volume of HLW slurry containing most of the solids and most of the radioactivity. Many of the vessels in the pretreatment facility will contain pulse jet mixers (PJMs) that will provide some or all of the mixing in the vessels. This technology was selected for use in so-called “black cell” regions of the WTP, where maintenance capability will not be available for the operating life of the WTP. PJM technology was selected for use in these regions because it has no moving mechanical parts that require maintenance. The vessels with the most concentrated slurries will also be mixed with air spargers and/or steady jets in addition to the mixing provided by the PJMs. …
Date: March 3, 2008
Creator: Pfund, David M.; Bontha, Jagannadha R.; Michener, Thomas E.; Nigl, Franz; Yokuda, Satoru T.; Leigh, Richard J. et al.
System: The UNT Digital Library