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56 MHZ Cavity Prototype Measurements (open access)

56 MHZ Cavity Prototype Measurements

None
Date: January 2, 2009
Creator: Hahn,H. & Choi, E.
Object Type: Report
System: The UNT Digital Library
56 MHZ Cavity Prototype Measurements (open access)

56 MHZ Cavity Prototype Measurements

N/A
Date: January 1, 2009
Creator: H., Hahn & Choi, E.
Object Type: Report
System: The UNT Digital Library
300 Area D4 Project Fiscal Year 2007 Building Completion Report (open access)

300 Area D4 Project Fiscal Year 2007 Building Completion Report

This report documents the deactivation, decontamination, decommissioning, and demolition (D4) of twenty buildings in the 300 Area of the Hanford Site. The D4 of these facilties included characterization, engineering, removal of hazardous and radiologically contaminated materials, equipment removal, utility disconnection, deactivation, decontamination, demolition of the structure, and stabilization or removal of the remaining slab and foundation, as appropriate.
Date: January 15, 2009
Creator: Westberg, R. A.
Object Type: Report
System: The UNT Digital Library
300 Area D4 Project Fiscal Year 2008 Building Completion Report (open access)

300 Area D4 Project Fiscal Year 2008 Building Completion Report

This report documents the deactivation, decontamination, decommissioning, and demolition (D4) of eighteen buildings in the 300 Area of the Hanford Site that were demolished in Fiscal Year 2008. The D4 of these facilties included characterization, engineering, removal of hazardous and radiologically contaminated materials, equipment removal, utility disconnection, deactivation, decontamination, demolition of the structure, and stabilization or removal of the remaining slab and foundation, as appropriate.
Date: January 15, 2009
Creator: Westberg, R. A.
Object Type: Report
System: The UNT Digital Library
1Surface structure of cleaved (001) USB2 single crystal surface (open access)

1Surface structure of cleaved (001) USB2 single crystal surface

We have achieved what we believe to be the first atomic resolution STM images for a uranium compound USb2 taken at room temperature. The a, b, and c lattice parameters in the images confirm that the tetragonal USb2crystals cleave on the (00 I) basal plane as expected. Our calculations indicate a symmetric cut between Sb planes to be the most favorable cleavage plane and U atoms to be responsible for most ofthe density of states measured by STM. Since the spacing between Sb atoms and between U atoms is the same, STM topography only cannot unambiguously identify the surface atom species.
Date: January 1, 2009
Creator: Chen, Shao-ping
Object Type: Article
System: The UNT Digital Library
2008 Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site (open access)

2008 Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site

This report is a compilation of the groundwater sampling results from the Area 5 Radioactive Waste Management Site (RWMS) including calendar year 2008 results. Each of the three Pilot Wells was sampled on March 11, 2008, and September 10, 2008. These wells were sampled for the following indicators of contamination: pH, specific conductance, total organic carbon, total organic halides, and tritium. Indicators of general water chemistry (cations and anions) were also monitored. Results from all samples collected in 2008 were within the limits established by agreement with the Nevada Division of Environmental Protection for each analyte. These data indicate that there has been no measurable impact to the uppermost aquifer from the Area 5 RWMS. There were no significant changes in measured groundwater parameters compared to previous years. Other information in the report includes an updated Cumulative Chronology for the Area 5 RWMS Groundwater Monitoring Program and a brief description of the site hydrogeology.
Date: January 13, 2009
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
2008 Wind Energy Projects, Wind Powering America (Poster) (open access)

2008 Wind Energy Projects, Wind Powering America (Poster)

The Wind Powering America program produces a poster at the end of every calendar year that depicts new U.S. wind energy projects. The 2008 poster includes the following projects: Stetson Wind Farm in Maine; Dutch Hill Wind Farm in New York; Grand Ridge Wind Energy Center in Illinois; Hooper Bay, Alaska; Forestburg, South Dakota; Elbow Creek Wind Project in Texas; Glacier Wind Farm in Montana; Wray, Colorado; Smoky Hills Wind Farm in Kansas; Forbes Park Wind Project in Massachusetts; Spanish Fork, Utah; Goodland Wind Farm in Indiana; and the Tatanka Wind Energy Project on the border of North Dakota and South Dakota.
Date: January 1, 2009
Creator: unknown
Object Type: Article
System: The UNT Digital Library
3D design activities at Fermilab: Opportunities for physics (open access)

3D design activities at Fermilab: Opportunities for physics

Fermilab began exploring the technologies for vertically integrated circuits (also commonly known as 3D circuits) in 2006. These technologies include through silicon vias (TSV), circuit thinning, and bonding techniques to replace conventional bump bonds. Since then, the interest within the High Energy Physics community has grown considerably. This paper will present an overview of the activities at Fermilab over the last 3 years which have helped spark this interest.
Date: January 1, 2009
Creator: Yarema, Raymond; Deptuch, Grezgorz; Hoff, Jim; Shenai, Alpana; Trimpl, Marcel; Zimmerman, Tom et al.
Object Type: Article
System: The UNT Digital Library
Ab-initio calculations of the hydrogen-uranium system. Part I: Surface phenomena, absorption, transport and trapping (open access)

Ab-initio calculations of the hydrogen-uranium system. Part I: Surface phenomena, absorption, transport and trapping

Density functional theory was applied to the initial steps of uranium hydriding: surface phenomena, absorption, bulk transport and trapping. H adsorbs exothermically to the (0 0 1) surface, yet H absorption into the bulk is endothermic, with off-center octahedral absorption having the lowest absorption energy of 0.39 eV, relative to molecular H{sub 2}. H absorption in interstitial sites causes a local softening of the bulk modulus. Diffusion of H in unstrained {alpha}-U has a barrier of 0.6 eV. The energy of H absorption adjacent to the chemical impurities C, S, Si was lowered by an amount proportional to the size of the impurity atom, and the resulting lattice strain Si > S > C. Thus, impurities may promote hydriding by providing surfaces or prestrained zones for H uptake.
Date: January 1, 2009
Creator: Taylor, Christopher D & Lillard, R Scott
Object Type: Article
System: The UNT Digital Library
Accelerating the disposition of transuranic waste from LANL - 9495 (open access)

Accelerating the disposition of transuranic waste from LANL - 9495

Los Alamos National Laboratory (LANL) was established during World War II with a single mission -- to design and build an atomic bomb. In the 65 years since, nuclear weapons physics, design and engineering have been the Laboratory's primary and sustaining mission. Experimental and process operations -- and associated cleanout and upgrade activities -- have generated a significant inventory of transuranic (TRU) waste that is stored at LANL's Technical Area 54, Material Disposal Area G (MDA G). When the Waste Isolation Pilot Plant (WIPP) opened its doors in 1999, LANL's TRU inventory totaled about 10,200 m{sup 3}, with a plutonium 239-equivalent curie (PE Ci) content of approximately 250,000 curies. By December 2008, a total of about 2,300 m3 (61,000 PE Ci) had been shipped to WIPP from LANL. This has resulted in a net reduction of about 1,000 m{sup 3} of TRU inventory over that time frame. This paper presents progress in dispositioning legacy and newly-generated transuranic waste (TRU) from ongoing missions at the LANL. The plans for, and lessons learned, in dispositioning several hundred high-activity TRU waste drums are reviewed. This waste population was one of the highest risks at LANL. Technical challenges in disposition of the high-activity drums …
Date: January 1, 2009
Creator: Shepard, Mark D; Stiger, Susan G; Blankenhorn, James A; Rael, George J & Moody, David C
Object Type: Article
System: The UNT Digital Library
ACRF Instrumentation Status: New, Current, and Future - December 2008 (open access)

ACRF Instrumentation Status: New, Current, and Future - December 2008

The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.
Date: January 15, 2009
Creator: Voyles, J. W.
Object Type: Report
System: The UNT Digital Library
Adaptive anisotropic meshing for steady convection-dominated problems (open access)

Adaptive anisotropic meshing for steady convection-dominated problems

Obtaining accurate solutions for convection–diffusion equations is challenging due to the presence of layers when convection dominates the diffusion. To solve this problem, we design an adaptive meshing algorithm which optimizes the alignment of anisotropic meshes with the numerical solution. Three main ingredients are used. First, the streamline upwind Petrov–Galerkin method is used to produce a stabilized solution. Second, an adapted metric tensor is computed from the approximate solution. Third, optimized anisotropic meshes are generated from the computed metric tensor by an anisotropic centroidal Voronoi tessellation algorithm. Our algorithm is tested on a variety of two-dimensional examples and the results shows that the algorithm is robust in detecting layers and efficient in avoiding non-physical oscillations in the numerical approximation.
Date: January 1, 2009
Creator: Nguyen, Hoa; Gunzburger, Max; Ju, Lili & Burkardt, John
Object Type: Article
System: The UNT Digital Library
Adaptive management: a paradigm for remediation of public facilities (open access)

Adaptive management: a paradigm for remediation of public facilities

Public facility restoration planning traditionally focused on response to natural disasters and hazardous materials accidental releases. These plans now need to integrate response to terrorist actions. Therefore, plans must address a wide range of potential vulnerabilities. Similar types of broad remediation planning are needed for restoration of waste and hazardous material handling areas and facilities. There are strong similarities in damage results and remediation activities between unintentional and terrorist actions; however, the uncertainties associated with terrorist actions result in a re-evaluation of approaches to planning. Restoration of public facilities following a release of a hazardous material is inherently far more complex than in confined industrial settings and has many unique technical, economic, social, and political challenges. Therefore, they arguably involve a superset of drivers, concerns and public agencies compared to other restoration efforts. This superset of conditions increases complexity of interactions, reduces our knowledge of the initial conditions, and even condenses the timeline for restoration response. Therefore, evaluations of alternative restoration management approaches developed for responding to terrorist actions provide useful knowledge for large, complex waste management projects. Whereas present planning documents have substantial linearity in their organization, the 'adaptive management' paradigm provides a constructive parallel operations paradigm for restoration …
Date: January 1, 2009
Creator: Janecky, David R; Whicker, Jeffrey J & Doerr, Ted B
Object Type: Article
System: The UNT Digital Library
Advanced Fuel Cycle Economic Analysis of Symbiotic Light-Water Reactor and Fast Burner Reactor Systems (open access)

Advanced Fuel Cycle Economic Analysis of Symbiotic Light-Water Reactor and Fast Burner Reactor Systems

The Advanced Fuel Cycle Economic Analysis of Symbiotic Light-Water Reactor and Fast Burner Reactor Systems, prepared to support the U.S. Advanced Fuel Cycle Initiative (AFCI) systems analysis, provides a technology-oriented baseline system cost comparison between the open fuel cycle and closed fuel cycle systems. The intent is to understand their overall cost trends, cost sensitivities, and trade-offs. This analysis also improves the AFCI Program’s understanding of the cost drivers that will determine nuclear power’s cost competitiveness vis-a-vis other baseload generation systems. The common reactor-related costs consist of capital, operating, and decontamination and decommissioning costs. Fuel cycle costs include front-end (pre-irradiation) and back-end (post-iradiation) costs, as well as costs specifically associated with fuel recycling. This analysis reveals that there are large cost uncertainties associated with all the fuel cycle strategies, and that overall systems (reactor plus fuel cycle) using a closed fuel cycle are about 10% more expensive in terms of electricity generation cost than open cycle systems. The study concludes that further U.S. and joint international-based design studies are needed to reduce the cost uncertainties with respect to fast reactor, fuel separation and fabrication, and waste disposition. The results of this work can help provide insight to the cost-related factors …
Date: January 1, 2009
Creator: Shropshire, D. E.
Object Type: Report
System: The UNT Digital Library
Advanced Thermoelectric Materials for Efficient Waste Heat Recovery in Process Industries (open access)

Advanced Thermoelectric Materials for Efficient Waste Heat Recovery in Process Industries

The overall objective of the project was to integrate advanced thermoelectric materials into a power generation device that could convert waste heat from an industrial process to electricity with an efficiency approaching 20%. Advanced thermoelectric materials were developed with figure-of-merit ZT of 1.5 at 275 degrees C. These materials were not successfully integrated into a power generation device. However, waste heat recovery was demonstrated from an industrial process (the combustion exhaust gas stream of an oxyfuel-fired flat glass melting furnace) using a commercially available (5% efficiency) thermoelectric generator coupled to a heat pipe. It was concluded that significant improvements both in thermoelectric material figure-of-merit and in cost-effective methods for capturing heat would be required to make thermoelectric waste heat recovery viable for widespread industrial application.
Date: January 6, 2009
Creator: Polcyn, Adam & Khaleel, Moe
Object Type: Report
System: The UNT Digital Library
Advanced Water-Gas Shift Membrane Reactor (open access)

Advanced Water-Gas Shift Membrane Reactor

The overall objectives for this project were: (1) to identify a suitable PdCu tri-metallic alloy membrane with high stability and commercially relevant hydrogen permeation in the presence of trace amounts of carbon monoxide and sulfur; and (2) to identify and synthesize a water gas shift catalyst with a high operating life that is sulfur and chlorine tolerant at low concentrations of these impurities. This work successfully achieved the first project objective to identify a suitable PdCu tri-metallic alloy membrane composition, Pd{sub 0.47}Cu{sub 0.52}G5{sub 0.01}, that was selected based on atomistic and thermodynamic modeling alone. The second objective was partially successful in that catalysts were identified and evaluated that can withstand sulfur in high concentrations and at high pressures, but a long operating life was not achieved at the end of the project. From the limited durability testing it appears that the best catalyst, Pt-Re/Ce{sub 0.333}Zr{sub 0.333}E4{sub 0.333}O{sub 2}, is unable to maintain a long operating life at space velocities of 200,000 h{sup -1}. The reasons for the low durability do not appear to be related to the high concentrations of H{sub 2}S, but rather due to the high operating pressure and the influence the pressure has on the WGS reaction …
Date: January 7, 2009
Creator: Emerson, Sean; Vanderspurt, Thomas; Opalka, Susanne; Radhakrishnan, Rakesh & Willigan, Rhonda
Object Type: Report
System: The UNT Digital Library
Advanced Waveform Simulation for Seismic Monitoring Events (open access)

Advanced Waveform Simulation for Seismic Monitoring Events

Abstract We conduct a detailed test of a recently developed technique, CAPloc, in recovering source parameters from a few stations against results from a large broadband network in Southern California. The method uses a library of 1D Green’s functions which are broken into segments and matched to waveform observations with adjustable timing shifts. These shifts can be established by calibration against a distribution of well-located earthquakes and assembled in tomographic images for predicting various phase-delays. Synthetics generated from 2D cross-sections through these models indicates that 1D synthetic waveforms are sufficient in modeling but simply shifted in time for most hard-rock sites. This simplification allows the source inversion for both mechanism and location to easily obtain by grid search. We test one-station mechanisms for 160 events against the array for both PAS and GSC which have data since 1960. While individual solutions work well (about 90%), joint solutions produce more reliable and defensible results. Inverting for both mechanism and location also works well except for certain complex paths across deep basins and along mountain ridges.
Date: January 27, 2009
Creator: Helmberger, Donald V.; Tromp, Jeroen & Rodgers, Arthur J.
Object Type: Report
System: The UNT Digital Library
Advances in Dust Detection and Removal for Tokamaks (open access)

Advances in Dust Detection and Removal for Tokamaks

Dust diagnostics and removal techniques are vital for the safe operation of next step fusion devices such as ITER. In the tokamak environment, large particles or fi bers can fall on the electrostatic detector potentially causing a permanent short. An electrostatic dust detector developed in the laboratory is being applied to the National Spherical Torus Experiment (NSTX). We report on the development of a gas puff system that uses helium to clear such particles from the detector. Experiments at atmospheric pressure with varying nozzle designs, backing pressures, puff durations and exit fl ow orientations have given an optimal confi guration that effectively removes particles from a 25 cm² area. Similar removal effi ciencies were observed under a vacuum base pressure of 1 mTorr. Dust removal from next step tokamaks will be required to meet regulatory dust limits. A tri-polar grid of fi ne interdigitated traces has been designed that generates an electrostatic traveling wave for conveying dust particles to a “drain.” First trials with only two working electrodes have shown particle motion in optical microscope images.
Date: January 1, 2009
Creator: Campos, A. & Skinner, C. H.
Object Type: Article
System: The UNT Digital Library
An Affordable Digitizer, Final Report (open access)

An Affordable Digitizer, Final Report

Design of prototype low cost high speed digitizers for physics applications
Date: January 4, 2009
Creator: Sumner, Dr. Richard
Object Type: Report
System: The UNT Digital Library
ALARA ASSESSMENT OF SETTLER SLUDGE SAMPLING METHODS (open access)

ALARA ASSESSMENT OF SETTLER SLUDGE SAMPLING METHODS

The purpose of this assessment is to compare underwater and above water settler sludge sampling methods to determine if the added cost for underwater sampling for the sole purpose of worker dose reductions is justified. Initial planning for sludge sampling included container, settler and knock-out-pot (KOP) sampling. Due to the significantly higher dose consequence of KOP sludge, a decision was made to sample KOP underwater to achieve worker dose reductions. Additionally, initial plans were to utilize the underwater sampling apparatus for settler sludge. Since there are no longer plans to sample KOP sludge, the decision for underwater sampling for settler sludge needs to be revisited. The present sampling plan calls for spending an estimated $2,500,000 to design and construct a new underwater sampling system (per A21 C-PL-001 RevOE). This evaluation will compare and contrast the present method of above water sampling to the underwater method that is planned by the Sludge Treatment Project (STP) and determine if settler samples can be taken using the existing sampling cart (with potentially minor modifications) while maintaining doses to workers As Low As Reasonably Achievable (ALARA) and eliminate the need for costly redesigns, testing and personnel retraining.
Date: January 30, 2009
Creator: LA, NELSEN
Object Type: Report
System: The UNT Digital Library
Algorithms for optimal dyadic decision trees (open access)

Algorithms for optimal dyadic decision trees

A new algorithm for constructing optimal dyadic decision trees was recently introduced, analyzed, and shown to be very effective for low dimensional data sets. This paper enhances and extends this algorithm by: introducing an adaptive grid search for the regularization parameter that guarantees optimal solutions for all relevant trees sizes, revising the core tree-building algorithm so that its run time is substantially smaller for most regularization parameter values on the grid, and incorporating new data structures and data pre-processing steps that provide significant run time enhancement in practice.
Date: January 1, 2009
Creator: Hush, Don & Porter, Reid
Object Type: Article
System: The UNT Digital Library
Alloys for 1000 degree C service in the Next Generation Nuclear Plant NERI 05-0191 (open access)

Alloys for 1000 degree C service in the Next Generation Nuclear Plant NERI 05-0191

The objective of the proposed research is to define strategies for the improvement of alloys for structural components, such as the intermediate heat exchanger and primary-to-secondary piping, for service at 1000 degree C in the He environment of the NGNP. Specifically, we will investigate the oxidation/carburization behavior and microstructure stability and how these processes affect creep. While generating this data, the project will also develop a fundamental understanding of how impurities in the He environment affect these degradation processes and how this understanding can be used to develop more useful life prediction methodologies.
Date: January 15, 2009
Creator: Was, Gary S.; Jones, J.W. & Pollock, T.
Object Type: Report
System: The UNT Digital Library
Alternative Donor--Acceptor Stacks from Crown Ethers and Naphthalene Diimide Derivatives: Rapid, Selective Formation from Solution and Solid State Grinding (open access)

Alternative Donor--Acceptor Stacks from Crown Ethers and Naphthalene Diimide Derivatives: Rapid, Selective Formation from Solution and Solid State Grinding

Self assembling {pi}-conjugated molecules into ordered structures are of increasing interest in the field of organic electronics. One particular example is charge transfer complexes containing columnar alternative donor-acceptor (ADA) stacks, where neutral and ionic ground states can be readily tuned to modulate electrical, optical, and ferroelectrical properties. Aromatic-aromatic and charge transfer interactions have been the leading driving forces in assisting the self-assembly of ADA stacks. Various folding structures containing ADA stacks were assembled in solution with the aid of solvophobic or ion-binding interactions. Meanwhile, examples of solid ADA stacks, which are more appealing for practical use in devices, were obtained from cocrystalization of binary components or mesophase assembly of liquid crystals in bulk blends. Regardless of these examples, faster and more controllable approaches towards precise supramolecular order in the solid state are still highly desirable.
Date: January 22, 2009
Creator: Lawrence Berkeley National Laboratory. Advanced Light Source.
Object Type: Article
System: The UNT Digital Library
ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE (open access)

ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE

Hydrogen storage is one of the challenges to be overcome for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods. The direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali metal alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, …
Date: January 9, 2009
Creator: Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B & Joshua Gray, J
Object Type: Article
System: The UNT Digital Library