Physical Sciences 2007 Science & Technology Highlights (open access)

Physical Sciences 2007 Science & Technology Highlights

The Physical Sciences Directorate applies frontier physics and technology to grand challenges in national security. Our highly integrated and multidisciplinary research program involves collaborations throughout Lawrence Livermore National Laboratory, the National Nuclear Security Administration, the Department of Energy, and with academic and industrial partners. The Directorate has a budget of approximately $150 million, and a staff of approximately 350 employees. Our scientists provide expertise in condensed matter and high-pressure physics, plasma physics, high-energy-density science, fusion energy science and technology, nuclear and particle physics, accelerator physics, radiation detection, optical science, biotechnology, and astrophysics. This document highlights the outstanding research and development activities in the Physical Sciences Directorate that made news in 2007. It also summarizes the awards and recognition received by members of the Directorate in 2007.
Date: April 7, 2008
Creator: Hazi, A U
Object Type: Report
System: The UNT Digital Library
Quantifying uncertainties of a Soil-Foundation Structure-Interaction System under Seismic Excitation (open access)

Quantifying uncertainties of a Soil-Foundation Structure-Interaction System under Seismic Excitation

We applied a spectrum of uncertainty quantification (UQ) techniques to the study of a two-dimensional soil-foundation-structure-interaction (2DSFSI) system (obtained from Professor Conte at UCSD) subjected to earthquake excitation. In the process we varied 19 uncertain parameters describing material properties of the structure and the soil. We present in detail the results for the different stages of our UQ analyses.
Date: April 7, 2008
Creator: Tong, C
Object Type: Report
System: The UNT Digital Library
Radiographic Capabilities of the MERCURY Monte Carlo Code (open access)

Radiographic Capabilities of the MERCURY Monte Carlo Code

MERCURY is a modern, parallel, general-purpose Monte Carlo code being developed at the Lawrence Livermore National Laboratory. Recently, a radiographic capability has been added. MERCURY can create a source of diagnostic, virtual particles that are aimed at pixels in an image tally. This new feature is compared to the radiography code, HADES, for verification and timing. Comparisons for accuracy were made using the French Test Object and for timing were made by tracking through an unstructured mesh. In addition, self consistency tests were run in MERCURY for the British Test Object and scattering test problem. MERCURY and HADES were found to agree to the precision of the input data. HADES appears to run around eight times faster than the MERCURY in the timing study. Profiling the MERCURY code has turned up several differences in the algorithms which account for this. These differences will be addressed in a future release of MERCURY.
Date: April 7, 2008
Creator: McKinley, M. Scott & Schach von Wittenau, Alexis E.
Object Type: Article
System: The UNT Digital Library
The dipole picture in DIS: saturation and heavy quarks (open access)

The dipole picture in DIS: saturation and heavy quarks

We discuss the description of the proton structure function within the dipole factorization framework. We parameterize the forward dipole amplitude to account for saturation as predicted by the small-x QCD evolution equations. Contrarily to previous models, the saturation scale does not decrease when taking heavy quarks into account. We show that the same dipole amplitude also allows to reproduce diffractive data and exclusive vector meson production.
Date: April 7, 2008
Creator: Soyez,G.
Object Type: Article
System: The UNT Digital Library
A Method to Increase Current Density in a Mono Element Internal Tin Processed Superconductor Utilizing Zr Oxide to Refine Grain Size (open access)

A Method to Increase Current Density in a Mono Element Internal Tin Processed Superconductor Utilizing Zr Oxide to Refine Grain Size

The effect of Oxygen on (Nb1Zr)3Sn multifilament conductors manufactured by the Mono Element Internal Tin (MEIT) process was explored to improve the current density by refining the grain size. This followed work first done by General Electric on the Nb3Sn tape process. Techniques to fabricate the more difficult Nb1Zr composites are described and allowed fabrication of long lengths of .254 mm diameter wire from an 88.9 mm diameter billet. Oxygen was incorporated through the use of SnO2 mixed with tin powder and incorporated into the core. These were compared to samples with Ti+Sn and Cu+Sn cores. Heat treatments covered the range of 700 C to 1000 C. Current density vs. H, grain size, and reaction percentages are provided for the materials tested. The Oxygen gave superior results in the temperature range of 815-1000 C. It also stabilized the filament geometry of the array in comparison to the other additions at the higher temperatures. At 815 C a peak in layer Jc yielded values of 2537 A/mm2 at 12 T and 1353 A/mm2 at 15T, 8-22% and 30-73% greater respectively than 700 C values. Results with Oxygen at high temperature show the possibility of high speed continuous reaction of the composite …
Date: April 7, 2008
Creator: Bruce A. Zeitlin, Eric Gregory
Object Type: Report
System: The UNT Digital Library
High Spectral Resolution X-ray Observation of Magnetic CVs: EX Hya (open access)

High Spectral Resolution X-ray Observation of Magnetic CVs: EX Hya

In magnetic cataclysmic variables (CVs) the primary is a highly magnetized white dwarf (WD) whose field controls the accretion flow close to the WD, leading to a shock and accretion column that radiate chiefly in X-rays. We present preliminary results from a 500 ks Chandra HETG observation of the brightest magnetic CV EX Hya. From the observational dataset we are able to measure the temperature and density at different points of the cooling accretion column using sensitive line ratios. We also construct line-based light curves to search for rotational modulation of the X-ray emission.
Date: April 7, 2008
Creator: Luna, G; Brickhouse, N S & Mauche, C W
Object Type: Article
System: The UNT Digital Library
Glucose Regulates the Expression of the Apolipoprotein A5 Gene (open access)

Glucose Regulates the Expression of the Apolipoprotein A5 Gene

The apolipoprotein A5 gene (APOA5) is a key player in determining triglyceride concentrations in humans and mice. Since diabetes is often associated with hypertriglyceridemia, this study explores whether APOA5 gene expression is regulated by alteration in glucose homeostasis and the related pathways. D-glucose activates APOA5 gene expression in a time- and dose-dependent manner in hepatocytes, and the glycolytic pathway involved was determined using D-glucose analogs and metabolites. Together, transient transfections, electrophoretic mobility shift assays and chromatin immunoprecipitation assays show that this regulation occurs at the transcriptional level through an increase of USF1/2 binding to an E-box in the APOA5 promoter. We show that this phenomenon is not due to an increase of mRNA or protein expression levels of USF. Using protein phosphatases 1 and 2A inhibitor, we demonstrate that D-glucose regulates APOA5 gene via a dephosphorylation mechanism, thereby resulting in an enhanced USF1/2-promoter binding. Last, subsequent suppressions of USF1/2 and phosphatases mRNA through siRNA gene silencing abolished the regulation. We demonstrate that APOA5 gene is up regulated by D-glucose and USF through phosphatase activation. These findings may provide a new cross talk between glucose and lipid metabolism.
Date: April 7, 2008
Creator: Fruchart, Jamila; Nowak, Maxime; Helleboid-Chapman, Audrey; Jakel, Heidelinde; Moitrot, Emmanuelle; Rommens, Corinne et al.
Object Type: Article
System: The UNT Digital Library
Analysis of Percent On-Cell Reformation of Methane in SOFC Stacks: Thermal, Electrical and Stress Analysis (open access)

Analysis of Percent On-Cell Reformation of Methane in SOFC Stacks: Thermal, Electrical and Stress Analysis

This report summarizes a parametric analysis performed to determine the effect of varying the percent on-cell reformation (OCR) of methane on the thermal and electrical performance for a generic, planar solid oxide fuel cell (SOFC) stack design. OCR of methane can be beneficial to an SOFC stack because the reaction (steam-methane reformation) is endothermic and can remove excess heat generated by the electrochemical reactions directly from the cell. The heat removed is proportional to the amount of methane reformed on the cell. Methane can be partially pre-reformed externally, then supplied to the stack, where rapid reaction kinetics on the anode ensures complete conversion. Thus, the thermal load varies with methane concentration entering the stack, as does the coupled scalar distributions, including the temperature and electrical current density. The endotherm due to the reformation reaction can cause a temperature depression on the anode near the fuel inlet, resulting in large thermal gradients. This effect depends on factors that include methane concentration, local temperature, and stack geometry.
Date: April 7, 2006
Creator: Recknagle, Kurtis P.; Yokuda, Satoru T.; Jarboe, Daniel T. & Khaleel, Mohammad A.
Object Type: Report
System: The UNT Digital Library
Nanoscale Synthesis and Characterization Laboratory Annual Report 2007 (open access)

Nanoscale Synthesis and Characterization Laboratory Annual Report 2007

The Nanoscale Synthesis and Characterization Laboratory's (NSCL) primary mission is to create and advance interdisciplinary research and development opportunities in nanoscience and technology. The NSCL is delivering on its mission providing Laboratory programs with scientific solutions through the use of nanoscale synthesis and characterization. While this annual report summarizes 2007 activities, we have focused on nanoporous materials, advanced high strength, nanostructured metals, novel 3-dimensional lithography and characterization at the nanoscale for the past 3 years. In these three years we have synthesized the first monolithic nanoporous metal foams with less than 10% relative density; we have produced ultrasmooth nanocrystalline diamond inertial confinement fusion capsules; we have synthesized 3-dimensional graded density structures from full density to 5% relative density using nanolithography; and we have established ultrasmall angle x-ray scattering as a non-destructive tool to determine the structure on the sub 300nm scale. The NSCL also has a mission to recruit and to train personnel for Lab programs. The NSCL continues to attract talented scientists to the Laboratory. Andrew Detor from Massachusetts Institute of Technology, Sutapa Ghosal from the University of California, Irvine, Xiang Ying Wang from Shanghai Institute of Technology, and Arne Wittstock from University of Bremen joined the NSCL this …
Date: April 7, 2008
Creator: Hamza, A V
Object Type: Report
System: The UNT Digital Library
Methods for Quantifying Uncertainty in Fast Reactor Analyses. (open access)

Methods for Quantifying Uncertainty in Fast Reactor Analyses.

Liquid-metal-cooled fast reactors in the form of sodium-cooled fast reactors have been successfully built and tested in the U.S. and throughout the world. However, no fast reactor has operated in the U.S. for nearly fourteen years. More importantly, the U.S. has not constructed a fast reactor in nearly 30 years. In addition to reestablishing the necessary industrial infrastructure, the development, testing, and licensing of a new, advanced fast reactor concept will likely require a significant base technology program that will rely more heavily on modeling and simulation than has been done in the past. The ability to quantify uncertainty in modeling and simulations will be an important part of any experimental program and can provide added confidence that established design limits and safety margins are appropriate. In addition, there is an increasing demand from the nuclear industry for best-estimate analysis methods to provide confidence bounds along with their results. The ability to quantify uncertainty will be an important component of modeling that is used to support design, testing, and experimental programs. Three avenues of UQ investigation are proposed. Two relatively new approaches are described which can be directly coupled to simulation codes currently being developed under the Advanced Simulation and …
Date: April 7, 2008
Creator: Fanning, T. H. & Fischer, P. F.
Object Type: Report
System: The UNT Digital Library
The SISCone and anti-k_t jet algorithms (open access)

The SISCone and anti-k_t jet algorithms

We illustrate how the midpoint and iterative cone (with progressive removal) algorithms fail to satisfy the fundamental requirements of infrared and collinear safety, causing divergences in the perturbative expansion. We introduce SISCone and the anti-k{sub t} algorithms as respective replacements that do not have those failures without any cost at the experimental level.
Date: April 7, 2008
Creator: Soyez,G.
Object Type: Article
System: The UNT Digital Library
Biological Review of the Hanford Solid Waste EIS - Borrow Area C (600 Area), Stockpile and Conveyance Road Area (600 Area), Environmental Restoration Disposal Facility (ERDF) (600 Area), Central Waste Complex (CWC) Expansion (200 West), 218-W-5 Expansion Area (200 West), New Waste Processing Facility (200 West)...ECR No. 2002-600-012b (open access)

Biological Review of the Hanford Solid Waste EIS - Borrow Area C (600 Area), Stockpile and Conveyance Road Area (600 Area), Environmental Restoration Disposal Facility (ERDF) (600 Area), Central Waste Complex (CWC) Expansion (200 West), 218-W-5 Expansion Area (200 West), New Waste Processing Facility (200 West)...ECR No. 2002-600-012b

This letter report is a supplement to the letter reports submitted previously under ECRs No. 2002-600-012 (Borrow Area C) and No. 2002-600-012a (CWC expansion). This letter report covers all areas that may be subject to surface disturbance under Alternative Groups A, B, C, D1, D2, D3, E1, E2, E3, and the No Action Alternative of the Hanford Solid Waste Environmental Impact Statement (HSW EIS), except for the following Low-Level Burial Grounds (LLBGs). The LLBGs proposed for use in the HSW EIS that are not subject of this letter report (218-W-3A, 218-W-3AE, 218-W 4B, 218-W-5, the developed portion of 218-W-4C, and the eastern half [except the northeastern corner] of 218-W-6 in the 200 West Area; and 218-E-10 and 218-E-12B in the 200 East Area) are surveyed annually. Annual letter reports concerning these are currently sent to Mr. Brett M. Barnes of Fluor Hanford, Inc. For the areas of surface disturbance described herein we provide a summary of field survey methods, survey results, and considerations and recommendations based on these results.
Date: April 7, 2003
Creator: Sackschewsky, Michael R.
Object Type: Report
System: The UNT Digital Library
Optical Properties of Passivated Silicon Nanoclusters: The Role of Synthesis (open access)

Optical Properties of Passivated Silicon Nanoclusters: The Role of Synthesis

The effect of preparation conditions on the structural and optical properties of silicon nanoparticles is investigated. Nanoscale reconstructions, unique to curved nanosurfaces, are presented for silicon nanocrystals and shown to have lower energy and larger optical gaps than bulk-derived structures. We find that high-temperature synthesis processes can produce metastable non-crystalline nanostructures with different core structures than bulk-derived crystalline clusters. The type of core structure that forms from a given synthesis process may depend on the passivation mechanism and time scale. The effect of oxygen on the optical of different types of silicon structures is calculated. In contrast to the behavior of bulk-like nanostructures, for non-crystalline and reconstructed crystalline structures surface oxygen atoms do not decrease the gap. In some cases, the presence of oxygen atoms at the nanocluster surface can significantly increase the optical absorption gap, due to decreased angular distortion of the silicon bonds. The relationship between strain and the optical gap in silicon nanoclusters is discussed.
Date: April 7, 2004
Creator: Draeger, E; Grossman, J; Williamson, A & Galli, G
Object Type: Article
System: The UNT Digital Library
13.2 nm Table-Top Inspection Microscope for Extreme Ultraviolet Lithography Mask Defect Characterization (open access)

13.2 nm Table-Top Inspection Microscope for Extreme Ultraviolet Lithography Mask Defect Characterization

We report on a reflection microscope that operates at 13.2-nm wavelength with a spatial resolution of 55{+-}3 nm. The microscope uses a table-top EUV laser to acquire images of photolithography masks in 20 seconds.
Date: April 7, 2009
Creator: Brizuela, F.; Wang, Y.; Brewer, C.; Pedaci, F.; Chao, W.; Anderson, E. et al.
Object Type: Article
System: The UNT Digital Library
Country Report on Building Energy Codes in India (open access)

Country Report on Building Energy Codes in India

This report is part of a series of reports on building energy efficiency codes in countries associated with the Asian Pacific Partnership (APP) - Australia, South Korea, Japan, China, India, and the United States of America. This reports gives an overview of the development of building energy codes in India, including national energy policies related to building energy codes, history of building energy codes in India, recent national projects and activities to promote building energy codes. The report also provides a review of current building energy codes (such as building envelope, HVAC, lighting, and water heating) for commercial buildings in India.
Date: April 7, 2009
Creator: Evans, Meredydd; Shui, Bin & Somasundaram, Sriram
Object Type: Report
System: The UNT Digital Library
A Modelica-based Model Library for Building Energy and Control Systems (open access)

A Modelica-based Model Library for Building Energy and Control Systems

This paper describes an open-source library with component models for building energy and control systems that is based on Modelica, an equation-based objectoriented language that is well positioned to become the standard for modeling of dynamic systems in various industrial sectors. The library is currently developed to support computational science and engineering for innovative building energy and control systems. Early applications will include controls design and analysis, rapid prototyping to support innovation of new building systems and the use of models during operation for controls, fault detection and diagnostics. This paper discusses the motivation for selecting an equation-based object-oriented language. It presents the architecture of the library and explains how base models can be used to rapidly implement new models. To demonstrate the capability of analyzing novel energy and control systems, the paper closes with an example where we compare the dynamic performance of a conventional hydronic heating system with thermostatic radiator valves to an innovative heating system. In the new system, instead of a centralized circulation pump, each of the 18 radiators has a pump whose speed is controlled using a room temperature feedback loop, and the temperature of the boiler is controlled based on the speed of the …
Date: April 7, 2009
Creator: Wetter, Michael
Object Type: Article
System: The UNT Digital Library
A DATA-CENTERED COLLABORATION PORTAL TO SUPPORT GLOBAL CARBON-FLUX ANALYSIS (open access)

A DATA-CENTERED COLLABORATION PORTAL TO SUPPORT GLOBAL CARBON-FLUX ANALYSIS

Carbon-climate, like other environmental sciences, has been changing. Large-scalesynthesis studies are becoming more common. These synthesis studies are often conducted by science teams that are geographically distributed and on datasets that are global in scale. A broad array of collaboration and data analytics tools are now available that could support these science teams. However, building tools that scientists actually use is hard. Also, moving scientists from an informal collaboration structure to one mediated by technology often exposes inconsistencies in the understanding of the rules of engagement between collaborators. We have developed a scientific collaboration portal, called fluxdata.org, which serves the community of scientists providing and analyzing the global FLUXNET carbon-flux synthesis dataset. Key things we learned or re-learned during our portal development include: minimize the barrier to entry, provide features on a just-in-time basis, development of requirements is an on-going process, provide incentives to change leaders and leverage the opportunity they represent, automate as much as possible, and you can only learn how to make it better if people depend on it enough to give you feedback. In addition, we also learned that splitting the portal roles between scientists and computer scientists improved user adoption and trust. The fluxdata.org portal …
Date: April 7, 2009
Creator: Agarwal, Deborah A.; Humphrey, Marty; Beekwilder, Norm; Jackson, Keith; Goode, Monte & van Ingen, Catharine
Object Type: Article
System: The UNT Digital Library
Semi-inclusive DIS:Factorization (open access)

Semi-inclusive DIS:Factorization

In this talk, we win present a QCD factorization theorem for the semi-inclusive deep-inelastic scattering with hadrons in the current fragmentation region detected at low transverse momentum.
Date: April 7, 2008
Creator: Yuan,F.
Object Type: Article
System: The UNT Digital Library
Dark Matter in the MSSM (open access)

Dark Matter in the MSSM

We have recently examined a large number of points in the parameter space of the phenomenological MSSM, the 19-dimensional parameter space of the CP-conserving MSSM with Minimal Flavor Violation. We determined whether each of these points satisfied existing experimental and theoretical constraints. This analysis provides insight into general features of the MSSM without reference to a particular SUSY breaking scenario or any other assumptions at the GUT scale. This study opens up new possibilities for SUSY phenomenology both in colliders and in astrophysical experiments. Here we shall discuss the implications of this analysis relevant to the study of dark matter.
Date: April 7, 2009
Creator: Cotta, R. C.; Gainer, J. S.; Hewett, J. L. & Rizzo, T. G.
Object Type: Article
System: The UNT Digital Library
Integrated Building Energy Systems Design Considering Storage Technologies (open access)

Integrated Building Energy Systems Design Considering Storage Technologies

The addition of storage technologies such as flow batteries, conventional batteries, and heat storage can improve the economic, as well as environmental attraction of micro-generation systems (e.g., PV or fuel cells with or without CHP) and contribute to enhanced demand response. The interactions among PV, solar thermal, and storage systems can be complex, depending on the tariff structure, load profile, etc. In order to examine the impact of storage technologies on demand response and CO2 emissions, a microgrid's distributed energy resources (DER) adoption problem is formulated as a mixed-integer linear program that can pursue two strategies as its objective function. These two strategies are minimization of its annual energy costs or of its CO2 emissions. The problem is solved for a given test year at representative customer sites, e.g., nursing homes, to obtain not only the optimal investment portfolio, but also the optimal hourly operating schedules for the selected technologies. This paper focuses on analysis of storage technologies in micro-generation optimization on a building level, with example applications in New York State and California. It shows results from a two-year research projectperformed for the U.S. Department of Energy and ongoing work. Contrary to established expectations, our results indicate that PV …
Date: April 7, 2009
Creator: Stadler, Michael; Marnay, Chris; Siddiqui, Afzal; Lai, Judy & Aki, Hirohisa
Object Type: Article
System: The UNT Digital Library
Infrastructure for Collaborative Protein Structure Prediction (open access)

Infrastructure for Collaborative Protein Structure Prediction

This project was designed to promote comparison and exchange of results within the protein structure prediction community.
Date: April 7, 2006
Creator: Moult, J.
Object Type: Report
System: The UNT Digital Library
Design of a Robotic Welding System for Closure of Waste Storage Canisters (open access)

Design of a Robotic Welding System for Closure of Waste Storage Canisters

This work reported here was done to provide a conceptual design for a robotic welding and inspection system for the Yucca Mountain Repository waste package closure system. The welding and inspection system is intended to make the various closure welds that seal and/or structurally join the lids to the waste package vessels. The welding and inspection system will also perform surface and volumetric inspections of the various closure welds and has the means to repair closure welds, if required. The system is designed to perform these various activities remotely, without the necessity of having personnel in the closure cell.
Date: April 7, 2005
Creator: Smartt, H. B.; Watkins, A. D.; Pace, D. P.; Bitsoi, R. J.; McJunkin, E. D. & Tolle, C. R.
Object Type: Report
System: The UNT Digital Library
Energy Production from Zoo Animal Wastes (open access)

Energy Production from Zoo Animal Wastes

Elephant and rhinoceros dung was used to investigate the feasibility of generating methane from the dung. The Knoxville Zoo produces 30 cubic yards (23 m{sup 3}) of herbivore dung per week and cost of disposal of this dung is $105/week. The majority of this dung originates from the Zoo's elephant and rhinoceros population. The estimated weight of the dung is 20 metric tons per week and the methane production potential determined in experiments was 0.033 L biogas/g dung (0.020 L CH{sub 4}/g dung), and the digestion of elephant dung was enhanced by the addition of ammonium nitrogen. Digestion was better overall at 37 C when compared to digestion at 50 C. Based on the amount of dung generated at the Knoxville Zoo, it is estimated that two standard garden grills could be operated 24 h per day using the gas from a digester treating 20 metric ton herbivore dung per week.
Date: April 7, 2003
Creator: Klasson, KT
Object Type: Report
System: The UNT Digital Library
Transverse Spin Physics: Recent Developments (open access)

Transverse Spin Physics: Recent Developments

None
Date: April 7, 2008
Creator: Yuan,F.
Object Type: Article
System: The UNT Digital Library