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Hydrogen Production by Water Dissociation Using Ceramic Membranes. Annual Report for FY 2007
The objective of this project is to develop dense ceramic membranes that, without using an external power supply or circuitry, can produce hydrogen via coal/coal gas-assisted water dissociation. This project grew out of an effort to develop a dense ceramic membrane for separating hydrogen from gas mixtures such as those generated during coal gasification, methane partial oxidation, and water-gas shift reactions [1]. That effort led to the development of various cermet (i.e., ceramic/metal composite) membranes that enable hydrogen to be produced by two methods. In one method, a hydrogen transport membrane (HTM) selectively removes hydrogen from a gas mixture by transporting it through either a mixed protonic/electronic conductor or a hydrogen transport metal. In the other method, an oxygen transport membrane (OTM) generates hydrogen mixed with steam by removing oxygen that is generated through water splitting [1, 2]. This project focuses on the development of OTMs that efficiently produce hydrogen via the dissociation of water. Supercritical boilers offer very high-pressure steam that can be decomposed to provide pure hydrogen by means of OTMs. Oxygen resulting from the dissociation of steam can be used for coal gasification, enriched combustion, or synthesis gas production. Hydrogen and sequestration-ready CO{sub 2} can be produced …
Date:
March 4, 2008
Creator:
Balachandran, U.; Chen, L.; Dorris, S. E.; Emerson, J. E.; Lee, T. H.; Park, C. Y. et al.
Object Type:
Report
System:
The UNT Digital Library
In Situ Microbial Community Control of the Stability of Bio-reduced Uranium
In aerobic aquifers typical of many Department of Energy (DOE) legacy waste sites, uranium is present in the oxidized U(VI) form which is more soluble and thus more mobile. Field experiments at the Old Rifle UMTRA site have demonstrated that biostimulation by electron donor addition (acetate) promotes biological U(VI) reduction (2). However, U(VI) reduction is reversible and oxidative dissolution of precipitated U(IV) after the cessation of electron donor addition remains a critical issue for the application of biostimulation as a treatment technology. Despite the potential for oxidative dissolution, field experiments at the Old Rifle site have shown that rapid reoxidation of bio-reduced uranium does not occur and U(VI) concentrations can remain at approximately 20% of background levels for more than one year. The extent of post-amendment U(VI) removal and the maintenance of bioreduced uranium may result from many factors including U(VI) sorption to iron-containing mineral phases, generation of H2S or FeS0.9, or the preferential sorption of U(VI) by microbial cells or biopolymers, but the processes controlling the reduction and in situ reoxidation rates are not known. To investigate the role of microbial community composition in the maintenance of bioreduced uranium, in-well sediment incubators (ISIs) were developed allowing field deployment of …
Date:
March 28, 2008
Creator:
Baldwin, Brett, R.; Peacock, Aaron, D.; Resch, Charles, T.; Arntzen, Evan; Smithgall, Amanda, N.; Pfiffner, Susan et al.
Object Type:
Report
System:
The UNT Digital Library
Next Generation Nuclear Plant Phenomena Identification and Ranking Tables (PIRTs) Volume 1: Main Report
A phenomena identification and ranking table (PIRT) process was conducted for the Next Generation Nuclear Plant (NGNP) design. This design (in the conceptual stage) is a modular high-temperature gas-cooled reactor (HTGR) that generates both electricity and process heat for hydrogen production. Expert panels identified safety-relevant phenomena, ranked their importance, and assessed the knowledge levels in the areas of accidents and thermal fluids, fission-product transport and dose, high-temperature materials, graphite, and process heat for hydrogen production. This main report summarizes and documents the process and scope of the reviews, noting the major activities and conclusions. The identified phenomena, analyses, rationales, and associated ratings of the phenomena, plus a summary of each panel's findings, are presented. Individual panel reports for these areas are provided as attached volumes to this main report and provide considerably more detail about each panel's deliberations as well as a more complete listing of the phenomena that were evaluated.
Date:
March 1, 2008
Creator:
Ball, Sydney J
Object Type:
Report
System:
The UNT Digital Library
Next Generation Nuclear Plant Phenomena Identification and Ranking Tables (PIRTs) Volume 2: Accident and Thermal Fluids Analysis PIRTs
An accident, thermal fluids, and reactor physics phenomena identification and ranking process was conducted by a panel of experts on the next generation nuclear plant (NGNP) design (consideration given to both pebble-bed and prismatic gas-cooled reactor configurations). Safety-relevant phenomena, importance, and knowledge base were assessed for the following event classes: (1) normal operation (including some reactor physics aspects), (2) general loss of forced circulation (G-LOFC), (3) pressurized loss-of-forced circulation (P-LOFC), (4) depressurized loss-of-forced circulation (D-LOFC), (5) air ingress (following D-LOFC), (6) reactivity transients - including anticipated transients without scram (ATWS), (7) processes coupled via intermediate heat exchanger (IHX) (IHX failure with molten salt), and (8) steam/water ingress. The panel's judgment of the importance ranking of a given phenomenon (or process) was based on the effect it had on one or more figures of merit or evaluation criteria. These included public and worker dose, fuel failure, and primary (and other safety) system integrity. The major phenomena of concern that were identified and categorized as high importance combined with medium to low knowledge follow: (1) core coolant bypass flows (normal operation), (2) power/flux profiles (normal operation), (3) outlet plenum flows (normal operation), (4) reactivity-temperature feedback coefficients for high-plutonium-content cores (normal operation and …
Date:
March 1, 2008
Creator:
Ball, Sydney J; Corradini, M.; Fisher, Stephen Eugene; Gauntt, R.; Geffraye, G.; Gehin, Jess C et al.
Object Type:
Report
System:
The UNT Digital Library
The Disparity Between Retail Gasoline and Diesel Fuel Prices
This report provides a brief overview of the differentiating retail gasoline and diesel fuel prices, including the factors influencing the differences.
Date:
March 31, 2008
Creator:
Bamberger, Robert L. & Pirog, Robert
Object Type:
Report
System:
The UNT Digital Library
[Response to Address Inquiry]
Email containing an address update from Kristopher Banks.
Date:
March 15, 2008
Creator:
Banks, Christopher
Object Type:
Text
System:
The UNT Digital Library
On Sub-linear Convergence for Linearly Degenerate Waves in Capturing Schemes
A common attribute of capturing schemes used to find approximate solutions to the Euler equations is a sub-linear rate of convergence with respect to mesh resolution. Purely nonlinear jumps, such as shock waves produce a first-order convergence rate, but linearly degenerate discontinuous waves, where present, produce sub-linear convergence rates which eventually dominate the global rate of convergence. The classical explanation for this phenomenon investigates the behavior of the exact solution to the numerical method in combination with the finite error terms, often referred to as the modified equation. For a first-order method, the modified equation produces the hyperbolic evolution equation with second-order diffusive terms. In the frame of reference of the traveling wave, the solution of a discontinuous wave consists of a diffusive layer that grows with a rate of t{sup 1/2}, yielding a convergence rate of 1/2. Self-similar heuristics for higher order discretizations produce a growth rate for the layer thickness of {Delta}t{sup 1/(p+1)} which yields an estimate for the convergence rate as p/(p+1) where p is the order of the discretization. In this paper we show that this estimated convergence rate can be derived with greater rigor for both dissipative and dispersive forms of the discrete error. In …
Date:
March 17, 2008
Creator:
Banks, J W; Aslam, T & Rider, W J
Object Type:
Article
System:
The UNT Digital Library
NAWIG News: The Quarterly Newsletter of the Native American Wind Interest Group, Spring 2008
The United States is home to more than 700 American Indian tribes and Native Alaska villages and corporations located on 96 million acres. Many of these tribes and villages have excellent wind resources that could be commercially developed to meet their electricity needs or for electricity export. The Wind Powering America program engages Native Americans in wind energy development, and as part of that effort, the NAWIG newsletter informs readers of events in the Native American/wind energy community. This issue features an interview with Steven J. Morello, director of DOE's newly formed Office of Indian Energy Policy and Programs, and a feature on the newly installed Vestas V-47 turbine at Turtle Mountain Community College.
Date:
March 1, 2008
Creator:
Baranowski, R.
Object Type:
Report
System:
The UNT Digital Library
Structural characterization of terrestrial microbial Mn oxides from Pinal Creek, AZ
The microbial catalysis of Mn(II) oxidation is believed to be a dominant source of abundant sorption- and redox-active Mn oxides in marine, freshwater, and subsurface aquatic environments. In spite of their importance, environmental oxides of known biogenic origin have generally not been characterized in detail from a structural perspective. Hyporheic zone Mn oxide grain coatings at Pinal Creek, Arizona, a metals-contaminated stream, have been identified as being dominantly microbial in origin and are well studied from bulk chemistry and contaminant hydrology perspectives. This site thus presents an excellent opportunity to study the structures of terrestrial microbial Mn oxides in detail. XRD and EXAFS measurements performed in this study indicate that the hydrated Pinal Creek Mn oxide grain coatings are layer-type Mn oxides with dominantly hexagonal or pseudo-hexagonal layer symmetry. XRD and TEM measurements suggest the oxides to be nanoparticulate plates with average dimensions on the order of 11 nm thick x 35 nm diameter, but with individual particles exhibiting thickness as small as a single layer and sheets as wide as 500 nm. The hydrated oxides exhibit a 10-A basal-plane spacing and turbostratic disorder. EXAFS analyses suggest the oxides contain layer Mn(IV) site vacancy defects, and layer Mn(III) is inferred …
Date:
March 19, 2008
Creator:
Bargar, John; Fuller, Christopher; Marcus, Matthew A.; Brearley, Adrian J.; Perez De la Rosa, M.; Webb, Samuel M. et al.
Object Type:
Article
System:
The UNT Digital Library
Framework for Proliferation Resistance and Physical Protection for Nonproliferation Impact Assessments.
This report describes a framework for proliferation resistance and physical protection evaluation for the fuel cycle systems envisioned in the expansion of nuclear power for electricity generation. The methodology is based on an approach developed as part of the Generation IV technical evaluation framework and on a qualitative evaluation approach to policy factors similar to those that were introduced in previous Nonproliferation Impact Assessments performed by DOE.
Date:
March 1, 2008
Creator:
Bari, R.
Object Type:
Report
System:
The UNT Digital Library
BAE/Orion Hybrid Electric Buses at New York City Transit: A Generational Comparison (Revised)
Paper describes the evaluation of hybrid-electric transit buses purchased by New York City Transit (NYCT) in an order group of 200 (Gen II) and compares their performance to those of similar hybrid-electric transit buses purchased by NYCT in an order group of 125 (Gen I).
Date:
March 1, 2008
Creator:
Barnitt, R.
Object Type:
Report
System:
The UNT Digital Library
Sustaining knowledge in the neutron generator community and benchmarking study.
In 2004, the Responsive Neutron Generator Product Deployment department embarked upon a partnership with the Systems Engineering and Analysis knowledge management (KM) team to develop knowledge management systems for the neutron generator (NG) community. This partnership continues today. The most recent challenge was to improve the current KM system (KMS) development approach by identifying a process that will allow staff members to capture knowledge as they learn it. This 'as-you-go' approach will lead to a sustainable KM process for the NG community. This paper presents a historical overview of NG KMSs, as well as research conducted to move toward sustainable KM.
Date:
March 1, 2008
Creator:
Barrentine, Tameka C.; Kennedy, Bryan C.; Saba, Anthony W.; Turgeon, Jennifer L.; Schneider, Julia Teresa; Stubblefield, William Anthony et al.
Object Type:
Report
System:
The UNT Digital Library
Sub-Scale Prototype Spent Nuclear Fuel/High Level Waste (SNF/HLW) Containers - B559010 REV 02
None
Date:
March 6, 2008
Creator:
Beardsley, M
Object Type:
Report
System:
The UNT Digital Library
Iron-Based Amorphous Coatings Produced by HVOF Thermal Spray Processing-Coating Structure and Properties
The feasibility to coat large SNF/HLW containers with a structurally amorphous material (SAM) was demonstrated on sub-scale models fabricated from Type 316L stainless steel. The sub-scale model were coated with SAM 1651 material using kerosene high velocity oxygen fuel (HVOF) torch to thicknesses ranging from 1 mm to 2 mm. The process parameters such as standoff distance, oxygen flow, and kerosene flow, were optimized in order to improve the corrosion properties of the coatings. Testing in an electrochemical cell and long-term exposure to a salt spray environment were used to guide the selection of process parameters.
Date:
March 26, 2008
Creator:
Beardsley, M B
Object Type:
Article
System:
The UNT Digital Library
Development of a low-power, low-cost front end electronics module for large scale distributed neutrino detectors
A number of concepts have been presented for distributed neutrino detectors formed of large numbers of autonomous detectors. Examples include the Antarctic Ross Ice Shelf Antenna Neutrino Array (ARIANNA) [Barwick 2006], as well as proposed radio extensions to the IceCube detector at South Pole Station such as AURA and IceRay. [Besson 2008]. We have focused on key enabling technical developments required by this class of experiments. The radio Cherenkov signal, generated by the Askaryan mechanism [Askaryan 1962, 1965], is impulsive and coherent up to above 1 GHz. In the frequency domain, the impulsive character of the emission results in simultaneous increase of the power detected in multiple frequency bands. This multiband triggering approach has proven fruitful, especially as anthropogenic interference often results from narrowband communications signals. A typical distributed experiment of this type consists of a station responsible for the readout of a cluster of antennas either near the surface of the ice or deployed in boreholes. Each antenna is instrumented with a broadband low-noise amplifier, followed by an array of filters to facilitate multi-band coincidence trigger schemes at the antenna level. The power in each band is detected at the output of each band filter, using either square-law diode …
Date:
March 8, 2008
Creator:
Beatty, James J. & Kass, Richard D.
Object Type:
Report
System:
The UNT Digital Library
Energy and Water Development: FY2009 Appropriations
None
Date:
March 18, 2008
Creator:
Behrens, Carl E.; Andrews, Anthony; Bearden, David M.; Carter, Nicole T.; Holt, Mark; Lane, Nic et al.
Object Type:
Report
System:
The UNT Digital Library
Basic Research Needs: Catalysis for Energy
The report presents results of a workshop held August 6-8, 2007, by DOE SC Basic Energy Sciences to determine the basic research needs for catalysis research.
Date:
March 11, 2008
Creator:
Bell, Alexis T.; Gates, Bruce C.; Ray, Douglas & Thompson, Michael R.
Object Type:
Report
System:
The UNT Digital Library
Calculation of asymptotic and RMS kicks due to higher order modes in the 3.9-GHz cavity
FLASH plans to use a 'third harmonic' (3.9 GHz) superconducting cavity to compensate nonlinear distortions of the longitudinal phase space due to the sinusoidal curvature of the cavity voltage of the TESLA 1.3 GHz cavities. Higher order modes (HOMs) in the 3.9 GHz have a significant impact on the dynamics of the electron bunches in a long bunch train. Kicks due to dipole modes can be enhanced along the bunch train depending on the frequency and Q-value of the modes. The enhancement factor for a constant beam offset with respect to the cavity has been calculated. A simple Monte Carlo model of these effects, allowing for scatter in HOM frequencies due to manufacturing variances, has also been implemented and results for both FLASH and for an XFEL-like configuration are presented.
Date:
March 1, 2008
Creator:
Bellantoni, L.; Edwards, H. & Wanzenberg, R.
Object Type:
Report
System:
The UNT Digital Library
Final Report for LDRD Project 06-ERD-063
None
Date:
March 10, 2008
Creator:
Beller, H R; Chakicherla, A; Coleman, M A; Esser, B K; Kane, S R; Legler, T C et al.
Object Type:
Report
System:
The UNT Digital Library
Battery Test Manual For Plug-In Hybrid Electric Ve
This battery test procedure manual was prepared fo
Date:
March 1, 2008
Creator:
Belt, Jeffrey
Object Type:
Report
System:
The UNT Digital Library
Use and selection of bridges as day roosts by Rafinesque's Big Eared Bats.
ABSTRACT.—Rafinesque’s big-eared bats (Corynorhinus rafinesquii) use bridges as day roosts in parts of their range, but information on bridge use across their range is lacking. From May to Aug. 2002 we surveyed 1129 bridges (12.5%) within all 46 counties of South Carolina to determine use and selection of bridges as day roosts by big-eared bats and to document their distribution across the state. During summer 2003, we visited 235 bridges in previously occupied areas of the state to evaluate short-term fidelity to bridge roosts. We found colonies and solitary big-eared bats beneath 38 bridges in 2002 and 54 bridges in 2003. Construction type and size of bridges strongly influenced use in both years; bats selected large, concrete girder bridges and avoided flat-bottomed slab bridges. The majority of occupied bridges (94.7%) were in the Upper and Lower Coastal Plains, but a few bridges (5.3%) were located in the Piedmont. Rafinesque’s big-eared bats were absent beneath bridges in the Blue Ridge Mountains. We established new records of occurrence for 10 counties. In the Coastal Plains, big-eared bats exhibited a high degree of short-term fidelity to roosts in highway bridges. For bridges that were occupied at least once, mean frequency of use was …
Date:
March 1, 2008
Creator:
Bennett, Frances, M.; Loeb, Susan, C.; Bunch, Mary, S. & Bowerman, William, W.
Object Type:
Article
System:
The UNT Digital Library
JV Task 90 - Activated Carbon Production from North Dakota Lignite
The Energy & Environmental Research Center (EERC) has pursued a research program for producing activated carbon from North Dakota lignite that can be competitive with commercial-grade activated carbon. As part of this effort, small-scale production of activated carbon was produced from Fort Union lignite. A conceptual design of a commercial activated carbon production plant was drawn, and a market assessment was performed to determine likely revenue streams for the produced carbon. Activated carbon was produced from lignite coal in both laboratory-scale fixed-bed reactors and in a small pilot-scale rotary kiln. The EERC was successfully able to upgrade the laboratory-scale activated carbon production system to a pilot-scale rotary kiln system. The activated carbon produced from North Dakota lignite was superior to commercial grade DARCO{reg_sign} FGD and Rheinbraun's HOK activated coke product with respect to iodine number. The iodine number of North Dakota lignite-derived activated carbon was between 600 and 800 mg I{sub 2}/g, whereas the iodine number of DARCO FGD was between 500 and 600 mg I{sub 2}/g, and the iodine number of Rheinbraun's HOK activated coke product was around 275 mg I{sub 2}/g. The EERC performed both bench-scale and pilot-scale mercury capture tests using the activated carbon made under various …
Date:
March 31, 2008
Creator:
Benson, Steven; Crocker, Charlene; Zaman, Rokan; Musich, Mark & Olson, Edwin
Object Type:
Report
System:
The UNT Digital Library
The Two-Loop Six-Point MHV Amplitude in Maximally Supersymmetric Yang-Mills Theory
We give a representation of the parity-even part of the planar two-loop six-gluon MHV amplitude of N = 4 super-Yang-Mills theory, in terms of loop-momentum integrals with simple dual conformal properties. We evaluate the integrals numerically in order to test directly the ABDK/BDS all-loop ansatz for planar MHV amplitudes. We find that the ansatz requires an additive remainder function, in accord with previous indications from strong-coupling and Regge limits. The planar six-gluon amplitude can also be compared with the hexagonal Wilson loop computed by Drummond, Henn, Korchemsky and Sokatchev in arXiv:0803.1466 [hep-th]. After accounting for differing singularities and other constants independent of the kinematics, we find that the Wilson loop and MHV-amplitude remainders are identical, to within our numerical precision. This result provides non-trivial confirmation of a proposed n-point equivalence between Wilson loops and planar MHV amplitudes, and suggests that an additional mechanism besides dual conformal symmetry fixes their form at six points and beyond.
Date:
March 12, 2008
Creator:
Bern, Z.; Dixon, L.J.; Kosower, D.A.; Roiban, R.; Spradlin, M.; Vergu, C. et al.
Object Type:
Article
System:
The UNT Digital Library
Field Validation of Toxicity Tests to Evaluate the Potential for Beneficial Use of Produced Water
This study investigated potential biological effects of produced water contamination derived from occasional surface overflow and possible subsurface intrusion at an oil production site along the shore of Skiatook Lake, Oklahoma. We monitored basic chemistry and acute toxicity to a suite of standard aquatic test species (fathead minnow-Pimephales promelas, Daphnia pulex, Daphnia magna, and Ceriodaphnia dubia) in produced water and in samples taken from shallow groundwater wells on the site. Toxicity identification evaluations and ion toxicity modeling were used to identify toxic constituents in the samples. Lake sediment at the oil production site and at a reference site were also analyzed for brine intrusion chemically and by testing sediment toxicity using the benthic invertebrates, Chironomus dilutus, and Hyallela azteca. Sediment quality was also assessed with in situ survival and growth studies with H. azteca and the Asian clam, Corbicula fluminea, and by benthic macroinvertebrate community sampling. The produced water was acutely toxic to the aquatic test organisms at concentrations ranging from 1% to 10% of the whole produced water sample. Toxicity identification evaluation and ion toxicity modeling indicated major ion salts and hydrocarbons were the primary mixture toxicants. The standardized test species used in the laboratory bioassays exhibited differences in …
Date:
March 31, 2008
Creator:
Bidwell, Joseph; Fisher, Jonathan & Cooper, Naomi
Object Type:
Report
System:
The UNT Digital Library