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U.S. Plans for the Next Fast Reactor Transmutation Fuels Irradiation Test (open access)

U.S. Plans for the Next Fast Reactor Transmutation Fuels Irradiation Test

The U.S. Advanced Fuel Cycle Initiative (AFCI) seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposal and the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is actinide-bearing transmutation fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. Metallic alloy and oxide fuel forms are being developed as the near term options for fast reactor implementation.
Date: September 1, 2007
Creator: Hilton, B. A.
Object Type: Article
System: The UNT Digital Library
Closure Report for Corrective Action Unit 484: Surface Debris, Waste Sites, and Burn Area, Tonopah Test Range, Nevada (open access)

Closure Report for Corrective Action Unit 484: Surface Debris, Waste Sites, and Burn Area, Tonopah Test Range, Nevada

File Part 2 of 10 (Comprises Appendices C through O, Library Distribution List, and Geophysics Data Images
Date: September 1, 2007
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
Closure Report for Corrective Action Unit 484: Surface Debris, Waste Sites, and Burn Area, Tonopah Test Range, Nevada (open access)

Closure Report for Corrective Action Unit 484: Surface Debris, Waste Sites, and Burn Area, Tonopah Test Range, Nevada

File Part 3 of 10 (Comprises Geophysics Data Images)
Date: September 1, 2007
Creator: National Security Technologies, LLC
Object Type: Report
System: The UNT Digital Library
Electrochemical Corrosion Testing of Borated Stainless Steel Alloys (open access)

Electrochemical Corrosion Testing of Borated Stainless Steel Alloys

The Department of Energy Office of Civilian Radioactive Waste Management has specified borated stainless steel manufactured to the requirements of ASTM A 887-89, Grade A, UNS S30464, to be the material used for the fabrication of the fuel basket internals of the preliminary transportation, aging, and disposal canister system preliminary design. The long-term corrosion resistance performance of this class of borated materials must be verified when exposed to expected YMP repository conditions after a waste package breach. Electrochemical corrosion tests were performed on crevice corrosion coupons of Type 304 B4 and Type 304 B5 borated stainless steels exposed to single postulated in-package chemistry at 60°C. The results show low corrosion rates for the test period
Date: September 1, 2007
Creator: lister, tedd e & Mizia, Ronald E
Object Type: Report
System: The UNT Digital Library
Search for resonant t anti-t production in p anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for resonant t anti-t production in p anti-p collisions at s**(1/2) = 1.96-TeV

We report on a search for narrow-width particles decaying to a top and antitop quark pair. The data set used in the analysis corresponds to an integrated luminosity of 680 pb{sup -1} collected with the Collider Detector at Fermilab in Run II. We present 95% confidence level upper limits on the cross section times branching ratio. Assuming a specific top color-assisted technicolor production model, the leptophobic Z{prime} with width {Gamma}{sub Z{prime}} = 0.012M{sub Z{prime}}, we exclude the mass range M{sub Z{prime}} < 725 GeV/c{sup 2} at the 95% confidence level.
Date: September 1, 2007
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Abulencia, A.; /Illinois U., Urbana; Adelman, J.; /Chicago U., EFI et al.
Object Type: Article
System: The UNT Digital Library
Interpretation of Recent Temperature Trends in California (open access)

Interpretation of Recent Temperature Trends in California

Regional-scale climate change and associated societal impacts result from large-scale (e.g. well-mixed greenhouse gases) and more local (e.g. land-use change) 'forcing' (perturbing) agents. It is essential to understand these forcings and climate responses to them, in order to predict future climate and societal impacts. California is a fine example of the complex effects of multiple climate forcings. The State's natural climate is diverse, highly variable, and strongly influenced by ENSO. Humans are perturbing this complex system through urbanization, irrigation, and emission of multiple types of aerosols and greenhouse gases. Despite better-than-average observational coverage, we are only beginning to understand the manifestations of these forcings in California's temperature record.
Date: September 21, 2007
Creator: Duffy, P B; Bonfils, C & Lobell, D
Object Type: Article
System: The UNT Digital Library
Guide to preparing SAND reports and other communication products : version 4. (open access)

Guide to preparing SAND reports and other communication products : version 4.

This guide describes the R&A process, Common Look and Feel requirements, and preparation and publishing procedures for communication products at Sandia National Laboratories. Samples of forms and examples of published communications products are provided. This guide takes advantage of the wealth of material now available on the Web as a resource. Therefore, it is best viewed as an electronic document. If some of the illustrations are too small to view comfortably, you can enlarge them on the screen as needed. The most significant changes since Version 1 involve the introduction of the electronic Review and Approval application at the Sandia/California (CA) and Sandia/New Mexico (NM) sites. Authors are advised to check the most current material on the application Web site before initiating the R&A process. The format of this document is considerably different than that expected of a SAND Report. It was selected to permit the large number of illustrations and examples to be placed closer to the text that references them. In the case of forms, covers, and other items that are included as examples, a link to the Web is provided so that you can access the items and download them for use.
Date: September 1, 2007
Creator: Brittenham, Phillip W.
Object Type: Report
System: The UNT Digital Library
Measured Peak Equipment Loads in Laboratories (open access)

Measured Peak Equipment Loads in Laboratories

This technical bulletin documents measured peak equipment load data from 39 laboratory spaces in nine buildings across five institutions. The purpose of these measurements was to obtain data on the actual peak loads in laboratories, which can be used to rightsize the design of HVAC systems in new laboratories. While any given laboratory may have unique loads and other design considerations, these results may be used as a 'sanity check' for design assumptions.
Date: September 12, 2007
Creator: Mathew, Paul A.
Object Type: Report
System: The UNT Digital Library
Watershed Restoration Project (open access)

Watershed Restoration Project

In 2003, the U.S. Department of Energy issued the Eastern Nevada Landscape Coalition (ENLC) funding to implement ecological restoration in Gleason Creek and Smith Valley Watersheds. This project was made possible by congressionally directed funding that was provided through the US Department of Energy, Energy Efficiency and Renewable Energy, Office of the Biomass Program. The Ely District Bureau of Land Management (Ely BLM) manages these watersheds and considers them priority areas within the Ely BLM district. These three entities collaborated to address the issues and concerns of Gleason Creek and Smith Valley and prepared a restoration plan to improve the watersheds’ ecological health and resiliency. The restoration process began with watershed-scale vegetation assessments and state and transition models to focus on restoration sites. Design and implementation of restoration treatments ensued and were completed in January 2007. This report describes the restoration process ENLC undertook from planning to implementation of two watersheds in semi-arid Eastern Nevada.
Date: September 27, 2007
Creator: Thompson, Julie & Macfarlan, Betsy
Object Type: Report
System: The UNT Digital Library
Aqueous Processing Material Accountability Instrumentation (open access)

Aqueous Processing Material Accountability Instrumentation

Increased use of nuclear power will require new facilities. The U.S. has not built a new spent nuclear fuel reprocessing facility for decades. Reprocessing facilities must maintain accountability of their nuclear fuel. This survey report on the techniques used in current aqueous reprocessing facilities, and provides references to source materials to assist facility design efforts.
Date: September 1, 2007
Creator: Bean, Robert
Object Type: Report
System: The UNT Digital Library
Structure-based inference of molecular functions of proteins of unknown function from Berkeley Structural Genomics Center (open access)

Structure-based inference of molecular functions of proteins of unknown function from Berkeley Structural Genomics Center

Advances in sequence genomics have resulted in an accumulation of a huge number of protein sequences derived from genome sequences. However, the functions of a large portion of them cannot be inferred based on the current methods of sequence homology detection to proteins of known functions. Three-dimensional structure can have an important impact in providing inference of molecular function (physical and chemical function) of a protein of unknown function. Structural genomics centers worldwide have been determining many 3-D structures of the proteins of unknown functions, and possible molecular functions of them have been inferred based on their structures. Combined with bioinformatics and enzymatic assay tools, the successful acceleration of the process of protein structure determination through high throughput pipelines enables the rapid functional annotation of a large fraction of hypothetical proteins. We present a brief summary of the process we used at the Berkeley Structural Genomics Center to infer molecular functions of proteins of unknown function.
Date: September 2, 2007
Creator: Kim, Sung-Hou; Shin, Dong Hae; Hou, Jingtong; Chandonia, John-Marc; Das, Debanu; Choi, In-Geol et al.
Object Type: Article
System: The UNT Digital Library
TEM Examination of Advanced Alloys Irradiated in ATR (open access)

TEM Examination of Advanced Alloys Irradiated in ATR

Successful development of materials is critical to the deployment of advanced nuclear power systems. Irradiation studies of candidate materials play a vital role for better understanding materials performance under various irradiation environments of advanced system designs. In many cases, new classes of materials have to be investigated to meet the requirements of these advanced systems. For applications in the temperature range of 500 800ºC which is relevant to the fast neutron spectrum burner reactors for the Global Nuclear Energy Partnership (GNEP) program, oxide dispersion strengthened (ODS) and ferritic martensitic steels (e.g., MA957 and others) are candidates for advanced cladding materials. In the low temperature regions of the core (<600ºC), alloy 800H, HCM12A (also called T 122) and HT 9 have been considered.
Date: September 1, 2007
Creator: Jian Gan, PhD
Object Type: Report
System: The UNT Digital Library
Synthesis and Characterization of Bimodal Nanoporous Cu Foams: Working Towards Inertial Fusion Energy (open access)

Synthesis and Characterization of Bimodal Nanoporous Cu Foams: Working Towards Inertial Fusion Energy

For the National Ignition Facility, at the Lawrence Livermore National Laboratory, nanoporous structures play a crucial role in the development of targets for high energy density experiments. Here we present a new bottom-up synthesis technique termed filter-casting for the creation of bimodal macro/nanoporous Cu structures. Homogeneous nanoporous monoliths can be synthesized using Cu nanoparticles and bimodal porosities can be achieved using sacrificial polystyrene spheres as a template. Control over the structure and composition is critical for target manufacturing. The measured densities of the Cu foam range between 1070-3390 mg/cm{sup 3}. Filter-casting is a powerful new method for directly synthesizing large nanoporous monoliths with predetermined composition, pore size, and pore structure.
Date: September 28, 2007
Creator: Cervantes, O; Hayes, J R & Hamza, A
Object Type: Article
System: The UNT Digital Library
Intelligent Control in Automation Based on Wireless Traffic Analysis (open access)

Intelligent Control in Automation Based on Wireless Traffic Analysis

Wireless technology is a central component of many factory automation infrastructures in both the commercial and government sectors, providing connectivity among various components in industrial realms (distributed sensors, machines, mobile process controllers). However wireless technologies provide more threats to computer security than wired environments. The advantageous features of Bluetooth technology resulted in Bluetooth units shipments climbing to five million per week at the end of 2005 [1, 2]. This is why the real-time interpretation and understanding of Bluetooth traffic behavior is critical in both maintaining the integrity of computer systems and increasing the efficient use of this technology in control type applications. Although neuro-fuzzy approaches have been applied to wireless 802.11 behavior analysis in the past, a significantly different Bluetooth protocol framework has not been extensively explored using this technology. This paper presents a new neurofuzzy traffic analysis algorithm of this still new territory of Bluetooth traffic. Further enhancements of this algorithm are presented along with the comparison against the traditional, numerical approach. Through test examples, interesting Bluetooth traffic behavior characteristics were captured, and the comparative elegance of this computationally inexpensive approach was demonstrated. This analysis can be used to provide directions for future development and use of this prevailing …
Date: September 1, 2007
Creator: Derr, Kurt & Manic, Milos
Object Type: Article
System: The UNT Digital Library

E85 and Biodiesel Deployment

Presentation outlines industry trends and statistics revolving around the use and production of ethanol and biodiesel.
Date: September 18, 2007
Creator: Harrow, G.
Object Type: Presentation
System: The UNT Digital Library
Mercury Oxidation via Catalytic Barrier Filters Phase II (open access)

Mercury Oxidation via Catalytic Barrier Filters Phase II

In 2004, the Department of Energy National Energy Technology Laboratory awarded the University of North Dakota a Phase II University Coal Research grant to explore the feasibility of using barrier filters coated with a catalyst to oxidize elemental mercury in coal combustion flue gas streams. Oxidized mercury is substantially easier to remove than elemental mercury. If successful, this technique has the potential to substantially reduce mercury control costs for those installations that already utilize baghouse barrier filters for particulate removal. Completed in 2004, Phase I of this project successfully met its objectives of screening and assessing the possible feasibility of using catalyst coated barrier filters for the oxidation of vapor phase elemental mercury in coal combustion generated flue gas streams. Completed in September 2007, Phase II of this project successfully met its three objectives. First, an effective coating method for a catalytic barrier filter was found. Second, the effects of a simulated flue gas on the catalysts in a bench-scale reactor were determined. Finally, the performance of the best catalyst was assessed using real flue gas generated by a 19 kW research combustor firing each of three separate coal types.
Date: September 30, 2007
Creator: Seames, Wayne; Mann, Michael; Muggli, Darrin; Hrdlicka, Jason & Horabik, Carol
Object Type: Report
System: The UNT Digital Library
Development of Advanced LED Phosphors by Spray-based Processes for Solid State Lighting (open access)

Development of Advanced LED Phosphors by Spray-based Processes for Solid State Lighting

The overarching goal of the project was to develop luminescent materials using aerosol processes for making improved LED devices for solid state lighting. In essence this means improving white light emitting phosphor based LEDs by improvement of the phosphor and phosphor layer. The structure of these types of light sources, displayed in Figure 1, comprises of a blue or UV LED under a phosphor layer that converts the blue or UV light to a broad visible (white) light. Traditionally, this is done with a blue emitting diode combined with a blue absorbing, broadly yellow emitting phosphor such as Y{sub 3}Al{sub 5}O{sub 12}:Ce (YAG). A similar result may be achieved by combining a UV emitting diode and at least three different UV absorbing phosphors: red, green, and blue emitting. These emitted colors mix to make white light. The efficiency of these LEDs is based on the combined efficiency of the LED, phosphor, and the interaction between the two. The Cabot SSL project attempted to improve the over all efficiency of the LED light source be improving the efficiency of the phosphor and the interaction between the LED light and the phosphor. Cabot's spray based process for producing phosphor powders is able …
Date: September 30, 2007
Creator: Corporation, Cabot
Object Type: Report
System: The UNT Digital Library
Development of an Immersed Boundary Method to Resolve Complex Terrain in the Weather Research and Forecasting Model (open access)

Development of an Immersed Boundary Method to Resolve Complex Terrain in the Weather Research and Forecasting Model

Flow and dispersion processes in urban areas are profoundly influenced by the presence of buildings which divert mean flow, affect surface heating and cooling, and alter the structure of turbulence in the lower atmosphere. Accurate prediction of velocity, temperature, and turbulent kinetic energy fields are necessary for determining the transport and dispersion of scalars. Correct predictions of scalar concentrations are vital in densely populated urban areas where they are used to aid in emergency response planning for accidental or intentional releases of hazardous substances. Traditionally, urban flow simulations have been performed by computational fluid dynamics (CFD) codes which can accommodate the geometric complexity inherent to urban landscapes. In these types of models the grid is aligned with the solid boundaries, and the boundary conditions are applied to the computational nodes coincident with the surface. If the CFD code uses a structured curvilinear mesh, then time-consuming manual manipulation is needed to ensure that the mesh conforms to the solid boundaries while minimizing skewness. If the CFD code uses an unstructured grid, then the solver cannot be optimized for the underlying data structure which takes an irregular form. Unstructured solvers are therefore often slower and more memory intensive than their structured counterparts. …
Date: September 4, 2007
Creator: Lunquist, K A; Chow, F K; Lundquist, J K & Mirocha, J D
Object Type: Article
System: The UNT Digital Library
Analysis of Images from Experiments Investigating Fragmentation of Materials (open access)

Analysis of Images from Experiments Investigating Fragmentation of Materials

Image processing techniques have been used extensively to identify objects of interest in image data and extract representative characteristics for these objects. However, this can be a challenge due to the presence of noise in the images and the variation across images in a dataset. When the number of images to be analyzed is large, the algorithms used must also be relatively insensitive to the choice of parameters and lend themselves to partial or full automation. This not only avoids manual analysis which can be time consuming and error-prone, but also makes the analysis reproducible, thus enabling comparisons between images which have been processed in an identical manner. In this paper, we describe our approach to extracting features for objects of interest in experimental images. Focusing on the specific problem of fragmentation of materials, we show how we can extract statistics for the fragments and the gaps between them.
Date: September 10, 2007
Creator: Kamath, C & Hurricane, O
Object Type: Report
System: The UNT Digital Library
Final Hazard Categorization for the Remediation of the 116-C-3 Chemical Waste Tanks (open access)

Final Hazard Categorization for the Remediation of the 116-C-3 Chemical Waste Tanks

This final hazard categorization (FHC) document examines the hazards, identifies appropriate controls to manage the hazards, and documents the commitments for the 116-C-3 Chemical Waste Tanks Remediation Project. The remediation activities analyzed in this FHC are based on recommended treatment and disposal alternatives described in the Engineering Evaluation for the Remediation to the 116-C-3 Chemical Waste Tanks (BHI 2005e).
Date: September 10, 2007
Creator: Blakley, T. M. & Schofield, W. D.
Object Type: Report
System: The UNT Digital Library
M-theory through the looking glass: Tachyon condensation in the E8 heterotic string (open access)

M-theory through the looking glass: Tachyon condensation in the E8 heterotic string

We study the spacetime decay to nothing in string theory and M-theory. First we recall a nonsupersymmetric version of heterotic M-theory, in which bubbles of nothing -- connecting the two E_8 boundaries by a throat -- are expected to be nucleated. We argue that the fate of this system should be addressed at weak string coupling, where the nonperturbative instanton instability is expected to turn into a perturbative tachyonic one. We identify the unique string theory that could describe this process: The heterotic model with one E_8 gauge group and a singlet tachyon. We then use worldsheet methods to study the tachyon condensation in the NSR formulation of this model, and show that it induces a worldsheet super-Higgs effect. The main theme of our analysis is the possibility of making meaningful alternative gauge choices for worldsheet supersymmetry, in place of the conventional superconformal gauge. We show in a version of unitary gauge how the worldsheet gravitino assimilates the goldstino and becomes dynamical. This picture clarifies recent results of Hellerman and Swanson. We also present analogs of R_\xi gauges, and note the importance of logarithmic CFT in the context of tachyon condensation.
Date: September 20, 2007
Creator: Horava, Petr; Horava, Petr & Keeler, Cynthia A.
Object Type: Article
System: The UNT Digital Library
Assessment of Computer Simulation Software and Process Data for High Pressure Die Casting of Magnesium (open access)

Assessment of Computer Simulation Software and Process Data for High Pressure Die Casting of Magnesium

Computer software for the numerical simulation of solidification and mold filling is an effective design tool for cast structural automotive magnesium components. A review of commercial software capabilities and their validation procedures was conducted. Aside form the software assessment, the program addressed five main areas: lubricant degradation, lubricant application, gate atomization, and heat transfer at metal mold interfaces. A test stand for lubricant application was designed. A sensor was used for the direct measurement of heat fluxes during lubricant application and casting solidification in graphite molds. Spray experiments were conducted using pure deionized water and commercial die lubricants. The results show that the sensor can be used with confidence for measuring heat fluxes under conditions specific to the die lube application. The data on heat flux was presented in forms suitable for use in HPDC simulation software. Severe jet breakup and atomization phenomena are likely to occur due to high gate velocities in HPDC. As a result of gate atomization, droplet flow affects the mold filling pattern, air entrapment, skin formation, and ensuing defects. Warm water analogue dies were designed for obtaining experimental data on mold filling phenomena. Data on break-up jet length, break-up pattern, velocities, and droplet size distribution …
Date: September 1, 2007
Creator: Sabau, Adrian S; Hatfield, Edward C; Dinwiddie, Ralph Barton; Kuwana, Kazunori; Viti, Valerio; Hassan, Mohamed I et al.
Object Type: Report
System: The UNT Digital Library
Evaluation of Fluid Conduction and Mixing within a Subassembly of the Actinide Burner Test Reactor (open access)

Evaluation of Fluid Conduction and Mixing within a Subassembly of the Actinide Burner Test Reactor

The RELAP5-3D code is being considered as a thermal-hydraulic system code to support the development of the sodium-cooled Actinide Burner Test Reactor as part of the Global Nuclear Energy Partnership. An evaluation was performed to determine whether the control system could be used to simulate the effects of non-convective mechanisms of heat transport in the fluid, including axial and radial heat conduction and subchannel mixing, that are not currently represented with internal code models. The evaluation also determined the relative importance of axial and radial heat conduction and fluid mixing on peak cladding temperature for a wide range of steady conditions and during a representative loss-of-flow transient. The evaluation was performed using a RELAP5-3D model of a subassembly in the Experimental Breeder Reactor-II, which was used as a surrogate for the Actinide Burner Test Reactor.
Date: September 1, 2007
Creator: Davis, Cliff B.
Object Type: Article
System: The UNT Digital Library
Impact of Including Higher Actinides in Fast Reactor Transmutation Analyses (open access)

Impact of Including Higher Actinides in Fast Reactor Transmutation Analyses

Previous fast reactor transmutation studies generally disregarded higher mass minor actinides beyond Cm-246 due to various considerations including deficiencies in nuclear cross-section data. Although omission of these higher mass actinides does not significantly impact the neutronic calculations and fuel cycle performance parameters follow-on neutron dose calculations related to fuel recycling, transportation and handling are significantly impacted. This report shows that including the minor actinides in the equilibrium fast reactor calculations will increase the predicted neutron emission by about 30%. In addition a sensitivity study was initiated by comparing the impact of different cross-section evaluation file for representing these minor actinides.
Date: September 1, 2007
Creator: Forget, B.; Asgari, M.; Ferrer, R. & Bays, S.
Object Type: Report
System: The UNT Digital Library