100-N Area Strontium-90 Treatability Demonstration Project: Phytoextraction Along the 100-N Columbia River Riparian Zone – Field Treatability Study (open access)

100-N Area Strontium-90 Treatability Demonstration Project: Phytoextraction Along the 100-N Columbia River Riparian Zone – Field Treatability Study

Strontium-90 (90Sr) is present both in the aquifer near the river and in the vadose and riparian zones of the river’s shore at 100-NR-2. Phytoextraction of 90Sr is being considered as a potential remediation system along the riparian zone of the Columbia River. Phytoextraction would employ coyote willow (Salix exigua). Past studies have shown that willow roots share uptake mechanisms for Sr with Ca, a plant macronutrient as well as no discrimination between Sr and 90Sr. Willow 90Sr concentration ratios [CR’s; (pCi 90Sr/g dry wt. of new growth tissue)/(pCi 90Sr/g soil porewater)] were consistently greater than 65 with three-quarters of the assimilated label partitioned into the above ground shoot. Insect herbivore experiments also demonstrated no significant potential for bioaccumulation or food chain transfer from their natural activities. The objectives of this field study were three-fold: (1) to demonstrate that a viable, “managed” plot of coyote willows can be established on the shoreline of the Columbia River that would survive the same microenvironment to be encountered at the 100-NR-2 shoreline; (2) to show through engineered barriers that large and small animal herbivores can be prevented from feeding on these plants; and (3) to show that once established, the plants will provide …
Date: January 11, 2010
Creator: Fellows, Robert J.; Fruchter, Jonathan S.; Driver, Crystal J. & Ainsworth, Calvin C.
Object Type: Report
System: The UNT Digital Library
2010 IRON-SULFUR ENZYMES GORDON RESEARCH CONFERENCE, JUNE 6-11, 2010 (open access)

2010 IRON-SULFUR ENZYMES GORDON RESEARCH CONFERENCE, JUNE 6-11, 2010

Iron-sulfur (FeS) centers are essential for biology and inspirational in chemistry. These protein cofactors are broadly defined as active sites in which Fe is coordinated by S-donor ligands, often in combination with extra non-protein components, for example, additional metal atoms such as Mo and Ni, and soft ligands such as CN{sup -} and CO. Iron-sulfur centers are inherently air sensitive: they are found in essentially all organisms and it is possible that they were integral components of the earliest forms of life, well before oxygen (O{sub 2}) appeared. Proteins containing FeS cofactors perform a variety of biological functions ranging across electron transfer, acid-base catalysis, and sensing where they are agents for cell regulation through transcription (DNA) or translation (RNA). They are redox catalysts for radical-based reactions and the activation of H{sub 2}, N{sub 2} and CO{sub 2}, processes that offer scientific and economic challenges for industry. Iron-sulfur centers provide the focus for fundamental investigations of chemical bonding, spectroscopy and paramagnetism, and their functions have numerous implications for health and medicine and applications for technology, including renewable energy. The 2010 Iron-Sulfur Enzymes GRC will bring together researchers from different disciplines for in-depth discussions and presentations of the latest developments. There will …
Date: June 11, 2010
Creator: Gray, Nancy Ryan
Object Type: Article
System: The UNT Digital Library
2010 MULTIPHOTON PROCESSES GORDON RESEARCH CONFERENCE, JUNE 6-11, 2010, TILTON, NH (open access)

2010 MULTIPHOTON PROCESSES GORDON RESEARCH CONFERENCE, JUNE 6-11, 2010, TILTON, NH

The Gordon Research Conference on Multiphoton Processes will be held for the 15th time in 2010. The meeting continues to evolve as it embraces both the rapid technological and intellectual growth in the field as well as the multi-disciplinary expertise of the participants. This time the sessions will focus on: (1) Ultrafast coherent control; (2) Free-electron laser experiments and theory; (3) Generation of harmonics and attosecond pulses; (4) Ultrafast imaging; (5) Applications of very high intensity laser fields; (6) Strong-field processes in molecules and solids; (7) Attosecond science; and (8) Controlling light. The scientific program will blur traditional disciplinary boundaries as the presenters and discussion leaders involve chemists, physicists, and optical engineers, representing both experiment and theory. The broad range of expertise and different perspectives of attendees should provide a stimulating and unique environment for solving problems and developing new ideas in this rapidly evolving field.
Date: June 11, 2010
Creator: Gaarde, Mette
Object Type: Article
System: The UNT Digital Library
Analysis of Failed and Nickel-coated 3093 Beam Clamp Components at the East Tennessee Technology Park (ettp) (open access)

Analysis of Failed and Nickel-coated 3093 Beam Clamp Components at the East Tennessee Technology Park (ettp)

The U.S. Department of Energy and its contractor, Bechtel Jacobs Company (BJC), are undertaking a major effort to clean up the former gaseous diffusion facility (K-25) located in Oak Ridge, TN. The decontamination and decommissioning activities require systematic removal of contaminated equipment and machinery followed by demolition of the buildings. As part of the cleanup activities, a beam clamp, used for horizontal life lines (HLLs) for fall protection, was discovered to be fractured during routine inspection. The beam clamp (yoke and D-ring) was a component in the HLL system purchased from Reliance Industries LLC. Specifically, the U-shaped stainless steel yoke of the beam clamp failed in a brittle mode at under less than 10% of the rated design capacity of 14,500 lb. The beam clamp had been in service for approximately 16 months. Bechtel Jacobs approached Argonne National Laboratory to assist in identifying the root cause of the failure of the beam clamp. The objectives of this study were to (1) review the prior reports and documents on the subject, (2) understand the possible failure mechanism(s) that resulted in the failed beam clamp components, (3) recommend approaches to mitigate the failure mechanism(s), and (4) evaluate the modified beam clamp assemblies. …
Date: October 11, 2010
Creator: Singh, D.; Pappacena, K.; Gaviria, J.; Burtsteva, T. & Division, Nuclear Engineering
Object Type: Report
System: The UNT Digital Library

Analysis of Hydrogen and Competing Technologies for Utility-Scale Energy Storage

Presentation about the National Renewable Energy Laboratory's analysis of hydrogen energy storage scenarios, including analysis framework, levelized cost comparison of hydrogen and competing technologies, analysis results, and conclusions drawn from the analysis.
Date: February 11, 2010
Creator: Steward, D.
Object Type: Presentation
System: The UNT Digital Library
Application Acceleration on Current and Future Cray Platforms (open access)

Application Acceleration on Current and Future Cray Platforms

None
Date: May 11, 2010
Creator: Koniges, A.; Preissl, R.; Kim, J.; Eder, D.; Fisher, A.; Masters, N. et al.
Object Type: Article
System: The UNT Digital Library
Autoignition behavior of unsaturated hydrocarbons in the low and high temperature regions (open access)

Autoignition behavior of unsaturated hydrocarbons in the low and high temperature regions

None
Date: January 11, 2010
Creator: Mehl, M; Pitz, W J; Westbrook, C K; Yasunaga, K & Curran, H J
Object Type: Article
System: The UNT Digital Library
Backscatter measurements for NIF ignition targets (open access)

Backscatter measurements for NIF ignition targets

None
Date: May 11, 2010
Creator: Moody, J. D.; Michel, P. A.; Bond, E.; Datte, P.; Krauter, K.; Glenzer, S. H. et al.
Object Type: Article
System: The UNT Digital Library
Cadmium Manganese Telluride (Cd1-xMnxTe): A potential material for room-temperature radiation detectors (open access)

Cadmium Manganese Telluride (Cd1-xMnxTe): A potential material for room-temperature radiation detectors

Cadmium Manganese Telluride (CdMnTe) recently emerged as a promising material for room-temperature X- and gamma-ray detectors. It offers several potential advantages over CdZnTe. Among them is its optimal tunable band gap ranging from 1.7-2.2 eV, and its relatively low (< 50%) content of Mn compared to that of Zn in CdZnTe that assures this favorable band-gap range. Another important asset is the segregation coefficient of Mn in CdTe that is approximately unity compared to 1.35 for Zn in CdZnTe, so ensuring the homogenous distribution of Mn throughout the ingot; hence, a large-volume stoichiometric yield is attained. However, some materials issues primarily related to the growth process impede the production of large, defect-free single crystals. The high bond-ionicity of CdMnTe entails a higher propensity to crystallize into a hexagonal structure rather than to adopt the expected zinc-blend structure, which is likely to generate twins in the crystals. In addition, bulk defects generate in the as-grown crystals due to the dearth of high-purity Mn, which yields a low-resistivity material. In this presentation, we report on our observations of such material defects in current CdMnTe materials, and our evaluation of its potential as an alternative detector material to the well-known CdZnTe detectors. We …
Date: July 11, 2010
Creator: Hossain, A.; Cui, Y.; Bolotnikov, A.; Camarda, G.; Yang, G.; Kim, K. H. et al.
Object Type: Article
System: The UNT Digital Library
Calibration and Characterization of the IceCube Photomultiplier Tube (open access)

Calibration and Characterization of the IceCube Photomultiplier Tube

Over 5,000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-inch diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resolution, late pulses and afterpulses are characterized. Because the PMTs are relatively large, the cathode sensitivity uniformity was measured. The absolute photon detection efficiency was calibrated using Rayleigh-scattered photons from a nitrogen laser. Measured characteristics are discussed in the context of their relevance to IceCube event reconstruction and simulation efforts.
Date: February 11, 2010
Creator: Collaboration, IceCube; Abbasi, R. & al., et
Object Type: Article
System: The UNT Digital Library
Characterizing high energy spectra of NIF ignition hohlraums using a differentially filtered high energy multi-pinhole X-ray imager (open access)

Characterizing high energy spectra of NIF ignition hohlraums using a differentially filtered high energy multi-pinhole X-ray imager

Understanding hot electron distributions generated inside hohlraums is important to the ignition campaign for controlling implosion symmetry and sources of preheat. While direct imaging of hot electrons is difficult, their spatial distribution and spectrum can be deduced by detecting high energy x-rays generated as they interact with the target materials. We used an array of 18 pinholes, with four independent filter combinations, to image entire hohlraums with a magnification of 0.87x during the hohlraum energetics campaign on NIF. Comparing our results with hohlraum simulations indicates that the characteristic 30 keV hot electrons are mainly generated from backscattered laser plasma interactions rather than from hohlraum hydrodynamics.
Date: May 11, 2010
Creator: Park, H.; Dewald, E. D.; Glenzer, S.; Kalantar, D. H.; Kilkenny, J. D.; MacGowan, B. J. et al.
Object Type: Article
System: The UNT Digital Library
Colling Wipe Samples for VX Analysis (open access)

Colling Wipe Samples for VX Analysis

This standard operating procedure (SOP) provides uniform procedures for the collection of wipe samples of VX residues from surfaces. Personnel may use this procedure to collect and handle wipe samples in the field. Various surfaces, including building materials (wood, metal, tile, vinyl, etc.) and equipment, may be sampled based on this procedure. The purpose of such sampling is to determine whether or not the relevant surfaces are contaminated, to determine the extent of their contamination, to evaluate the effectiveness of decontamination procedures, and to determine the amount of contaminant that might present as a contact hazard.
Date: February 11, 2010
Creator: Koester, C & Hoppes, W G
Object Type: Report
System: The UNT Digital Library
Commissioning of the LCLS LINAC (open access)

Commissioning of the LCLS LINAC

The Linac Coherent Light Source (LCLS) X-ray free electron laser project is currently under construction at the Stanford Linear Accelerator Center (SLAC). A new injector and upgrades to the existing accelerator were installed in two phases in 2006 and 2007. We report on the commissioning of the injector, the two new bunch compressors at 250MeV and 4.3 GeV, and transverse and longitudinal beam diagnostics up to the end of the existing linac at 13.6 GeV. The commissioning of the new transfer line from the end of the linac to the undulator is scheduled to start in November 2008 and for the undulator in March 2009 with first light to be expected in July 2009.
Date: June 11, 2010
Creator: Loos, H.; Akre, R.; Brachmann, A.; Decker, F. J.; Ding, Y.; Dowell, D. et al.
Object Type: Article
System: The UNT Digital Library
Compliance and Verification of Standards and Labelling Programs in China: Lessons Learned (open access)

Compliance and Verification of Standards and Labelling Programs in China: Lessons Learned

After implementing several energy efficiency standards and labels (30 products covered by MEPS, 50 products covered by voluntary labels and 19 products by mandatory labels), the China National Institute of Standardization (CNIS) is now implementing verification and compliance mechanism to ensure that the energy information of labeled products comply with the requirements of their labels. CNIS is doing so by organizing check testing on a random basis for room air-conditioners, refrigerators, motors, heaters, computer displays, ovens, and self -ballasted lamps. The purpose of the check testing is to understand the implementation of the Chinese labeling scheme and help local authorities establishing effective compliance mechanisms. In addition, to ensure robustness and consistency of testing results, CNIS has coordinated a round robin testing for room air conditioners. Eight laboratories (Chinese (6), Australian (1) and Japanese (1)) have been involved in the round robin testing and tests were performed on four sets of samples selected from manufacturer?s production line. This paper describes the methodology used in undertaking both check and round robin testing, provides analysis of testing results and reports on the findings. The analysis of both check and round robin testing demonstrated the benefits of a regularized verification and monitoring system for …
Date: June 11, 2010
Creator: Saheb, Yamina; Zhou, Nan; Fridley, David & Pierrot, André
Object Type: Article
System: The UNT Digital Library
Composition of the Earth's Inner Core from High-pressure Sound Velocity Measurements in Fe-Ni-Si alloys (open access)

Composition of the Earth's Inner Core from High-pressure Sound Velocity Measurements in Fe-Ni-Si alloys

None
Date: March 11, 2010
Creator: Antonangeli, D.; Siebert, J.; Badro, J.; Farber, D. L.; Fiquet, G.; Morard, G. et al.
Object Type: Article
System: The UNT Digital Library
Compression and strong rarefaction in high power impulse magnetron sputtering discharges (open access)

Compression and strong rarefaction in high power impulse magnetron sputtering discharges

Gas compression and strong rarefaction have been observed for high power impulse magnetron sputtering (HIPIMS) discharges using a copper target in argon. Time-resolved ion saturation currents of 35 probes were simultaneously recorded for HIPIMS discharges operating far above the self-sputtering runaway threshold. The argon background pressure was a parameter for the evaluation of the spatial and temporal development of the plasma density distribution. The data can be interpreted by a massive onset of the sputtering flux (sputter wind) that causes a transient densification of the gas, followed by rarefaction and the replacement of gas plasma by the metal plasma of sustained self-sputtering. The plasma density pulse follows closely the power pulse at low pressure. At high pressure, the relatively remote probes recorded a density peak only after the discharge pulse, indicative for slow, diffusive ion transport.
Date: November 11, 2010
Creator: Horwat, David & Anders, Andre
Object Type: Article
System: The UNT Digital Library
CONTAINMENT ANALYSIS METHODOLOGY FOR TRANSPORT OF BREACHED CLAD ALUMINUM SPENT FUEL (open access)

CONTAINMENT ANALYSIS METHODOLOGY FOR TRANSPORT OF BREACHED CLAD ALUMINUM SPENT FUEL

Aluminum-clad, aluminum-based spent nuclear fuel (Al-SNF) from foreign and domestic research reactors (FRR/DRR) is being shipped to the Savannah River Site and placed in interim storage in a water basin. To enter the United States, a cask with loaded fuel must be certified to comply with the requirements in the Title 10 of the U.S. Code of Federal Regulations, Part 71. The requirements include demonstration of containment of the cask with its contents under normal and accident conditions. Many Al-SNF assemblies have suffered corrosion degradation in storage in poor quality water, and many of the fuel assemblies are 'failed' or have through-clad damage. A methodology was developed to evaluate containment of Al-SNF even with severe cladding breaches for transport in standard casks. The containment analysis methodology for Al-SNF is in accordance with the methodology provided in ANSI N14.5 and adopted by the U. S. Nuclear Regulatory Commission in NUREG/CR-6487 to meet the requirements of 10CFR71. The technical bases for the inputs and assumptions are specific to the attributes and characteristics of Al-SNF received from basin and dry storage systems and its subsequent performance under normal and postulated accident shipping conditions. The results of the calculations for a specific case of …
Date: July 11, 2010
Creator: Vinson, D.
Object Type: Article
System: The UNT Digital Library
Cosmic Ray Spectra in Nambu-Goldstone Dark Matter Models (open access)

Cosmic Ray Spectra in Nambu-Goldstone Dark Matter Models

We discuss the cosmic ray spectra in annihilating/decaying Nambu-Goldstone dark matter models. The recent observed positron/electron excesses at PAMELA and Fermi experiments are well fitted by the dark matter with a mass of 3TeV for the annihilating model, while with a mass of 6TeV for the decaying model. We also show that the Nambu-Goldstone dark matter models predict a distinctive gamma-ray spectrum in a certain parameter space.
Date: June 11, 2010
Creator: Ibe, Masahiro; Murayama, Hitoshi; Shirai, Satoshi & Yanagida, Tsutomu T.
Object Type: Article
System: The UNT Digital Library
Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured Using Dynamic Mechanical Thermal Analysis with Liquid Nitrogen Cooling (open access)

Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured Using Dynamic Mechanical Thermal Analysis with Liquid Nitrogen Cooling

Dynamic mechanical thermal analysis (DMTA) of virgin TR-55 silicone rubber specimens was conducted. Two dynamic temperature sweep tests, 25 to -100 C and 25 to -70 to 0 C (ramp rate = 1 C/min), were conducted at a frequency of 6.28 rad/s (1 Hz) using a torsion rectangular test geometry. A strain of 0.1% was used, which was near the upper limit of the linear viscoelastic region of the material based on an initial dynamic strain sweep test. Storage (G{prime}) and loss (G{double_prime}) moduli, the ratio G{double_prime}/G{prime} (tan {delta}), and the coefficient of linear thermal expansion ({alpha}) were determined as a function of temperature. Crystallization occurred between -40 and -60 C, with G{prime} increasing from {approx}6 x 10{sup 6} to {approx}4 x 10{sup 8} Pa. The value of {alpha} was fairly constant before ({approx}4 x 10{sup -4} mm/mm- C) and after ({approx}3 x 10{sup -4} mm/mm- C) the transition, and peaked during the transition ({approx}3 x 10{sup -3} mm/mm- C). Melting occurred around -30 C upon heating.
Date: February 11, 2010
Creator: Small, W., IV & Wilson, T. S.
Object Type: Report
System: The UNT Digital Library
Detection, Classification and Estimation of Radioactive Contraband from Uncertain Low-Count Measurements (open access)

Detection, Classification and Estimation of Radioactive Contraband from Uncertain Low-Count Measurements

None
Date: March 11, 2010
Creator: Candy, J V
Object Type: Report
System: The UNT Digital Library
DOE-EPSCOR SPONSORED PROJECT FINAL REPORT (open access)

DOE-EPSCOR SPONSORED PROJECT FINAL REPORT

Concern over the quality of environmental management and restoration has motivated the model development for predicting water and solute transport in the vadose zone. Soil hydraulic properties are required inputs to subsurface models of water flow and contaminant transport in the vadose zone. Computer models are now routinely used in research and management to predict the movement of water and solutes into and through the vadose zone of soils. Such models can be used successfully only if reliable estimates of the soil hydraulic parameters are available. The hydraulic parameters considered in this project consist of the saturated hydraulic conductivity and four parameters of the water retention curves. To quantify hydraulic parameters for heterogeneous soils is both difficult and time consuming. The overall objective of this project was to better quantify soil hydraulic parameters which are critical in predicting water flows and contaminant transport in the vadose zone through a comprehensive and quantitative study to predict heterogeneous soil hydraulic properties and the associated uncertainties. Systematic and quantitative consideration of the parametric heterogeneity and uncertainty can properly address and further reduce predictive uncertainty for contamination characterization and environmental restoration at DOE-managed sites. We conducted a comprehensive study to assess soil hydraulic parameter …
Date: March 11, 2010
Creator: Zhu, Jianting
Object Type: Report
System: The UNT Digital Library
DRAINING HAZARDOUS FLUIDS DURING BUILDING 221-1F DEACTIVATION AT THE SAVANNAH RIVER SITE (open access)

DRAINING HAZARDOUS FLUIDS DURING BUILDING 221-1F DEACTIVATION AT THE SAVANNAH RIVER SITE

Several years ago, SRS completed a four year mission to decommission {approx}250 excess facilities. As part of that effort, SRS deactivated multiple facilities (e.g. Building 247-F, Naval Fuels Facility, and Building 211-F, Outside Facilities for F-Canyon) that contained extensive piping systems filled with hazardous material (e.g. nitric acid). Draining of hazardous materials from piping was successfully completed in all facilities without incident. In early 2009, the decommissioning program at SRS was restarted as a result of funding made available by the American Recovery & Reinvestment Act (ARRA). Under ARRA, draining of piping containing hazardous material was initiated in multiple facilities including Building 221-1F (or A-Line). This paper describes and reviews the draining of piping containing hazardous materials at A-Line, with emphasis on an incident involving the draining of nitric acid. The paper is intended to be a resource for engineers, planners, and project managers, who face similar draining challenges.
Date: May 11, 2010
Creator: Musall, J.
Object Type: Article
System: The UNT Digital Library
Driving Oxygen Coordinated Ligand Exchange at Nanocrystal Surfaces using Trialkylsilylated Chalcogenides (open access)

Driving Oxygen Coordinated Ligand Exchange at Nanocrystal Surfaces using Trialkylsilylated Chalcogenides

A general, efficient method is demonstrated for exchanging native oxyanionic ligands on inorganic nanocrystals with functional trimethylsilylated (TMS) chalcogenido ligands. In addition, newly synthesized TMS mixed chalcogenides leverage preferential reactivity of TMS-S bonds over TMS-O bonds, enabling efficient transfer of luminescent nanocrystals into aqueous media with retention of their optical properties.
Date: November 11, 2010
Creator: Caldwell, Marissa A.; Albers, Aaron E.; Levy, Seth C.; Pick, Teresa E.; Cohen, Bruce E.; Helms, Brett A. et al.
Object Type: Article
System: The UNT Digital Library
Dual Selectivity Expressed in [2+2+1] Dynamic Clipping of Unsymmetrical [2]Catenanes (open access)

Dual Selectivity Expressed in [2+2+1] Dynamic Clipping of Unsymmetrical [2]Catenanes

A {pi}-templated dynamic [2+2+1] clipping protocol is established for the synthesis of [2]catenanes from two parts dialdehyde, two parts diamine and one part tetracationic cyclophane. It is further diversified for the selective formation of an unsymmetrical [2]catenane showing great translational selectivity by employing two different dialdehydes in a one-pot reaction. The dual selectivity and the dynamic nature are verified by {sup 1}H NMR spectroscopy, X-ray single crystal structural studies and exchange experiments.
Date: June 11, 2010
Creator: Liu, Yi
Object Type: Article
System: The UNT Digital Library