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Subtask 1.23 - Mercury Removal from Barite the Oil Industry (open access)

Subtask 1.23 - Mercury Removal from Barite the Oil Industry

Drilling muds are used by the oil and gas industry to provide a seal and to float rock chips to the surface during the drilling process. Barite (naturally occurring barium sulfate ore) is commonly used as a weighting agent additive in drilling muds because it is chemically nonreactive and has a high specific gravity (between 4.2 and 4.25 at 20 C). Because of environmental concerns, barite used by the oil and gas industry in the Gulf of Mexico must be certified to contain less than 1 mg/kg of mercury. Faced with these regulations, the U.S. Gulf Coast oil industry has looked to foreign sources of low-mercury barite, primarily India and China. These sources tend to have high-grade barite deposits and relatively inexpensive domestic transportation costs; as of late, however, U.S. purchasers have been forced to pay increasing costs for shipping to U.S. grinding plants. The objective of this project was to demonstrate two mercury removal techniques for high-mercury barite sources. Two barite samples of unique origins underwent processing to reduce mercury to required levels. The chemical treatment with dilute acid removed a portion of the mercury in both barite samples. The desired concentration of 1 mg/kg was achieved in both …
Date: September 1, 2008
Creator: Holmes, Michael; Nyberg, Carolyn; Brandt, Katie; Eylands, Kurt; Fiala, Nathan & Dunham, Grant
Object Type: Report
System: The UNT Digital Library
Extraction of niobium and tantalum isotopes using organophosphorus compounds - Part I - Extraction of 'carrier-free' metal concentrations from HCl solutions (open access)

Extraction of niobium and tantalum isotopes using organophosphorus compounds - Part I - Extraction of 'carrier-free' metal concentrations from HCl solutions

The extraction of niobium (Nb) and tantalum (Ta) from hydrochloric acid media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) was studied. The goal of the experiments is to find a system that demonstrates selectivity between the members of group five of the Periodic Table and is also suitable for the study of dubnium (Db, Z = 105). Experiments were performed at the trace level (10-16 M Nb or Ta) using hydrochloric acid with concentrations ranging from 1 - 11 M and short-lived isotopes of Nb and Ta produced in nuclear reactions. When HDEHP was used as the extractant, the Nb extraction yield decreased with increasing acid concentrations above 6 M, while the amount of Ta extracted remained over 75percent for all acid concentrations studied. Tantalum was found to be extracted by BEHP at acid concentrations above 6 M, while niobium was not significantly extracted. The data obtained are used as the basis to discuss the speciation of Nb and Ta under the conditions studied and to evaluate possible extraction mechanisms.
Date: September 1, 2008
Creator: Gates, Jacklyn; Sudowe, Ralf; Stavsetra, Liv; Ali, Mazhar; Calvert, Michael; Dragojevic, Irena et al.
Object Type: Article
System: The UNT Digital Library
Capturing the uncertainty in adversary attack simulations. (open access)

Capturing the uncertainty in adversary attack simulations.

This work provides a comprehensive uncertainty technique to evaluate uncertainty, resulting in a more realistic evaluation of PI, thereby requiring fewer resources to address scenarios and allowing resources to be used across more scenarios. For a given set of dversary resources, two types of uncertainty are associated with PI for a scenario: (1) aleatory (random) uncertainty for detection probabilities and time delays and (2) epistemic (state of knowledge) uncertainty for the adversary resources applied during an attack. Adversary esources consist of attributes (such as equipment and training) and knowledge about the security system; to date, most evaluations have assumed an adversary with very high resources, adding to the conservatism in the evaluation of PI. The aleatory uncertainty in PI is ddressed by assigning probability distributions to detection probabilities and time delays. A numerical sampling technique is used to evaluate PI, addressing the repeated variable dependence in the equation for PI.
Date: September 1, 2008
Creator: Darby, John L.; Brooks, Traci N. & Berry, Robert Bruce
Object Type: Report
System: The UNT Digital Library
Measurement of the Λ<sup>0</sup><sub>b</sub> lifetime in Λ<sup>0</sup><sub>b</sub> → Λ<sup>+</sup><sub>c</sub>π<sup>-</sup> decays at the Collider Detector at Fermilab (open access)

Measurement of the Λ<sup>0</sup><sub>b</sub> lifetime in Λ<sup>0</sup><sub>b</sub> → Λ<sup>+</sup><sub>c</sub>π<sup>-</sup> decays at the Collider Detector at Fermilab

The lifetime of the Λ<sup>0</sup><sub>b</sub> baryon (consisting of u, d and b quarks) is the theoretically most interesting of all b-hadron lifetimes. The lifetime of Λ<sup>0</sup><sub>b</sub> probes our understanding of how baryons with one heavy quark are put together and how they decay. Experimentally however, measurements of the Λ<sup>0</sup><sub>b</sub> lifetime have either lacked precision or have been inconsistent with one another. This thesis describes the measurement of Λ<sup>0</sup><sub>b</sub> lifetime in proton-antiproton collisions with center of mass energy of 1.96 TeV at Fermilab's Tevatron collider. Using 1070 ± 60pb<sup>-1</sup> of data collected by the Collider Detector at Fermilab (CDF), a clean sample of about 3,000 fully-reconstructed Λ<sup>0</sup><sub>b</sub> →Λ<sub>c</sub><sup>+</sup>π<sup>-</sup> decays (with Λ<sup>+</sup><sub>c</sub> subsequently decaying via Λ<sup>+</sup><sub>c</sub> → p<sup>+</sup> K<sup>-</sup> π<sup>+</sup>) is used to extract the lifetime of the Λ<sup>0</sup><sub>b</sub> baryon, which is found to be cτ(Λ<sup>0</sup><sub>b</sub>) = 422.8 ± 13.8(stat) ± 8.8(syst)μm. This is the most precise measurement of its kind, and is even better than the current world average. It also settles the recent controversy regarding the apparent inconsistency between CDF's other measurement and the rest of the world.
Date: September 1, 2008
Creator: Mumford, Jonathan Reid
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Quality framework proposal for Component Material Evaluation (CME) projects. (open access)

Quality framework proposal for Component Material Evaluation (CME) projects.

This report proposes the first stage of a Quality Framework approach that can be used to evaluate and document Component Material Evaluation (CME) projects. The first stage of the Quality Framework defines two tools that will be used to evaluate a CME project. The first tool is used to decompose a CME project into its essential elements. These elements can then be evaluated for inherent quality by looking at the subelements that impact their level of quality maturity or rigor. Quality Readiness Levels (QRLs) are used to valuate project elements for inherent quality. The Framework provides guidance for the Principal Investigator (PI) and stakeholders for CME project prerequisites that help to ensure the proper level of confidence in the deliverable given its intended use. The Framework also Provides a roadmap that defined when and how the Framework tools should be applied. Use of these tools allow the Principal Investigator (PI) and stakeholders to understand what elements the project will use to execute the project, the inherent quality of the elements, which of those are critical to the project and why, and the risks associated to the project's elements.
Date: September 1, 2008
Creator: Christensen, Naomi G.; Arfman, John F. & Limary, Siviengxay
Object Type: Report
System: The UNT Digital Library
Beam Dynamics in a Muon Ionisation Cooling Channel (open access)

Beam Dynamics in a Muon Ionisation Cooling Channel

The Neutrino Factory has been proposed as a facility to provide an intense source of neutrinos suitable for the measurement of neutrino oscillation parameters and a possible CP violating phase to unprecedented precision. In the Neutrino Factory, neutrinos are produced by the decay of a muon beam with 20-50 GeV per muon. Initially, the muon beam occupies a large volume in phase space, which must be reduced before the beam can be accelerated. The proposed method to achieve this is to use a solenoidal ionisation colling channel.
Date: September 1, 2008
Creator: Rogers, Chris
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 88, No. 245, Ed. 1 Monday, September 1, 2008 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 88, No. 245, Ed. 1 Monday, September 1, 2008

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: September 1, 2008
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Hardware demonstration of high-speed networks for satellite applications. (open access)

Hardware demonstration of high-speed networks for satellite applications.

This report documents the implementation results of a hardware demonstration utilizing the Serial RapidIO{trademark} and SpaceWire protocols that was funded by Sandia National Laboratories (SNL's) Laboratory Directed Research and Development (LDRD) office. This demonstration was one of the activities in the Modeling and Design of High-Speed Networks for Satellite Applications LDRD. This effort has demonstrated the transport of application layer packets across both RapidIO and SpaceWire networks to a common downlink destination using small topologies comprised of commercial-off-the-shelf and custom devices. The RapidFET and NEX-SRIO debug and verification tools were instrumental in the successful implementation of the RapidIO hardware demonstration. The SpaceWire hardware demonstration successfully demonstrated the transfer and routing of application data packets between multiple nodes and also was able reprogram remote nodes using configuration bitfiles transmitted over the network, a key feature proposed in node-based architectures (NBAs). Although a much larger network (at least 18 to 27 nodes) would be required to fully verify the design for use in a real-world application, this demonstration has shown that both RapidIO and SpaceWire are capable of routing application packets across a network to a common downlink node, illustrating their potential use in real-world NBAs.
Date: September 1, 2008
Creator: Donaldson, Jonathon W. & Lee, David S.
Object Type: Report
System: The UNT Digital Library
Advanced Detector Research - Fabrication and Testing of 3D Active-Edge Silicon Sensors: High Speed, High Yield (open access)

Advanced Detector Research - Fabrication and Testing of 3D Active-Edge Silicon Sensors: High Speed, High Yield

Development of 3D silicon radiation sensors employing electrodes fabricated perpendicular to the sensor surfaces to improve fabrication yields and increasing pulse speeds.
Date: September 1, 2008
Creator: Parker, Sherwood I
Object Type: Report
System: The UNT Digital Library
Cathode Ion Bombardment in RF Photoguns (open access)

Cathode Ion Bombardment in RF Photoguns

N/A
Date: September 1, 2008
Creator: E., Pozdeyev; Kayran, D. & Litvinenko, V.
Object Type: Report
System: The UNT Digital Library
User Guide for UAL (C++ Interface) (open access)

User Guide for UAL (C++ Interface)

N/A
Date: September 1, 2008
Creator: N., Malitsky & Talman, R.
Object Type: Report
System: The UNT Digital Library
RESULTS OF TESTS TO DEMONSTRATE A SIX-INCH DIAMETER COATER FOR PRODUCTION OF TRISO-COATED PARTICLES FOR ADVANCED GAS REACTOR EXPERIMENTS (open access)

RESULTS OF TESTS TO DEMONSTRATE A SIX-INCH DIAMETER COATER FOR PRODUCTION OF TRISO-COATED PARTICLES FOR ADVANCED GAS REACTOR EXPERIMENTS

The Next Generation Nuclear Plant (NGNP)/Advanced Gas Reactor (AGR) Fuel Development and Qualification Program includes a series of irradiation experiments in Idaho National Laboratory's (INL's) Advanced Test Reactor. TRISOcoated particles for the first AGR experiment, AGR-1, were produced at Oak Ridge National Laboratory (ORNL) in a twoinch diameter coater. A requirement of the NGNP/AGR Program is to produce coated particles for later experiments in coaters more representative of industrial scale. Toward this end, tests have been performed by Babcock and Wilcox (B&amp;W) in a six-inch diameter coater. These tests are expected to lead to successful fabrication of particles for the second AGR experiment, AGR-2. While a thorough study of how coating parameters affect particle properties was not the goal of these tests, the test data obtained provides insight into process parameter/coated particle property relationships. Most relationships for the six-inch diameter coater followed trends found with the ORNL two-inch coater, in spite of differences in coater design and bed hydrodynamics. For example the key coating parameters affecting pyrocarbon anisotropy were coater temperature, coating gas fraction, total gas flow rate and kernel charge size. Anisotropy of the outer pyrolytic carbon (OPyC) layer also strongly correlates with coater differential pressure. In an effort …
Date: September 1, 2008
Creator: Marshall, Douglas W.
Object Type: Article
System: The UNT Digital Library
Hole doping in high temperature superconductors using the XANES technique (open access)

Hole doping in high temperature superconductors using the XANES technique

Superconducting and physical properties of F-doped HgPb-1223 and Ce-doped Tl-1223 systems were considerably improved through adjusting the hole content of the two systems. In this study, we have used the x-ray absorption near-edge structure (XANES) technique to investigate the electronic structure of the two systems by probing the unoccupied electronic states. For the F-doped Hg-1223 system, the O K-edge, Ca L{sub 2,3} and Cu L{sub 2,3}-edge structures were thoroughly investigated. The pre-edge features of O K-edge spectra, as a function of doping, reveal important information about the projected local density of unoccupied states on the O sites in the region close to the absorption edge, which is a measure of O 2p hole concentration in the valence band. In the originally under-doped Hg-1223, the results indicate that the number of O 2p holes in the CuO{sub 2} planes increases as fluorine was introduced up to an optimal value, after which it decreases. Furthermore, the Cu L{sub 2,3} absorption edge provides useful information about the valence state of Cu which is also related to the hole density in the CuO{sub 2} planes and confirms the same previous conclusion. The Ca L{sub 2,3}-edge shows the presence crystal field splitting in HgPb1223/F{sub x} …
Date: September 1, 2008
Creator: Hamdan, Nasser & Hussain, Zahid
Object Type: Article
System: The UNT Digital Library
Long-Term Surveillance and Maintenance Plan for the U.S. Department of Energy Amchitka, Alaska, Site (open access)

Long-Term Surveillance and Maintenance Plan for the U.S. Department of Energy Amchitka, Alaska, Site

This Long-Term Surveillance and Maintenance Plan describes how the U.S. Department of Energy (DOE) intends to fulfill its mission to maintain protection of human health and the environment at the Amchitka, Alaska, Site1. Three underground nuclear tests were conducted on Amchitka Island. The U.S. Department of Defense, in conjunction with the U.S. Atomic Energy Commission (AEC), conducted the first nuclear test (Long Shot) to provide data that would improve the United States' capability of detecting underground nuclear explosions. The second nuclear test (Milrow) was a weapons-related test conducted by AEC as a means to study the feasibility of detonating a much larger device. The final nuclear test (Cannikin), the largest United States underground test, was a weapons-related test. Surface disturbances associated with these tests have been remediated. However, radioactivity remains deep below the surface, contained in and around the test cavities, for which no feasible remediation technology has been identified. In 2006, the groundwater model (Hassan et al. 2002) was updated using 2005 data collected by the Consortium for Risk Evaluation with Stakeholder Participation. Model simulation results indicate there is no breakthrough or seepage of radionuclides into the marine environment within 2,000 years. The Amchitka conceptual model is reasonable; the …
Date: September 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Post-Closure Inspection and Monitoring Report for Corrective Action Unit 417: Central Nevada Test Area Surface, Hot Creek Valley, Nevada, for Calendar Year 2007 (open access)

Post-Closure Inspection and Monitoring Report for Corrective Action Unit 417: Central Nevada Test Area Surface, Hot Creek Valley, Nevada, for Calendar Year 2007

This report presents data collected during the annual post-closure site inspection conducted at the Central Nevada Test Area Surface Corrective Action Unit (CAU) 417 in May 2007. The annual post-closure site inspection included inspections of the UC-1, UC-3, and UC-4 sites in accordance with the Post-Closure Monitoring Plan provided in the CAU 417 Closure Report (NNSA/NV 2001). The annual inspection conducted at the UC-1 Central Mud Pit (CMP) indicated the site and soil cover were in good condition. No new cracks or fractures were observed in the soil cover during the annual inspection. A crack on the west portion of the cover was observed during the last quarterly inspection in December 2006. This crack was filled with bentonite as part of the maintenance activities conducted in February 2007 and will be monitored during subsequent annual inspections. The vegetation on the soil cover was adequate but showing signs of the area's ongoing drought. No issues were identified with the CMP fence, gate, or subsidence monuments. New DOE Office of Legacy Management signs with updated emergency phone numbers were installed as part of this annual inspection, no issues were identified with the warning signs and monuments at the other two UC-1 locations. …
Date: September 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
[Stonewall Democrats of Dallas Reminder] (open access)

[Stonewall Democrats of Dallas Reminder]

A printed email that lays out and explains all of the upcoming events that the Stonewall Democrats of Dallas have planned.
Date: September 1, 2008
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Letter of Gratitude from Texas Stonewall Democratic Caucus] (open access)

[Letter of Gratitude from Texas Stonewall Democratic Caucus]

Copy of a letter of gratitude from the Texas Stonewall Democratic Caucus addressed to Trey in response to his donation and attendance at a convention held on June 5, 2008. The letter is dated September 1, 2008.
Date: September 1, 2008
Creator: Texas Stonewall Democratic Caucus
Object Type: Letter
System: The UNT Digital Library
Analysis of HFIR Dosimetry Experiments Performed in Cycles 400 and 401 (open access)

Analysis of HFIR Dosimetry Experiments Performed in Cycles 400 and 401

The High Flux Isotope Reactor (HFIR) has been in operation at Oak Ridge National Laboratory since 1966. To upgrade and enhance capabilities for neutron science research at the reactor, a larger HB-2 beam tube was installed in April of 2002. To assess, experimentally, the impact of this larger beam tube on radiation damage rates [i.e., displacement-per-atom (dpa) rates] used in vessel life extension studies, dosimetry experiments were performed from April to August 2004 during fuel cycles 400 and 401. This report documents the analysis of the dosimetry experiments and the determination of best-estimate dpa rates. These dpa rates are obtained by performing a least-squares adjustment of calculated neutron and gamma-ray fluxes and the measured responses of radiometric monitors and beryllium helium accumulation fluence monitors. The best-estimate dpa rates provided here will be used to update HFIR pressure vessel life extension studies, which determine the pressure/temperature limits for reactor operation and the HFIR pressure vessel's remaining life. All irradiation parameters given in this report correspond to a reactor power of 85 MW.
Date: September 1, 2008
Creator: Remec, Igor & Baldwin, Charles A.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, September 1, 2008 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, September 1, 2008

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: September 1, 2008
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
FY08 MEMBRANE CHARACTERIZATION REPORT FOR HYBRID SULFUR ELECTROLYZER (open access)

FY08 MEMBRANE CHARACTERIZATION REPORT FOR HYBRID SULFUR ELECTROLYZER

This report summarizes results from all of the membrane testing completed to date at the Savannah River National Laboratory (SRNL) for the sulfur dioxide-depolarized electrolyzer (SDE). Several types of commercially-available membranes have been analyzed for ionic resistance and sulfur dioxide transport including perfluorinated sulfonic acid (PFSA), sulfonated polyether-ketone-ketone (SPEKK), and polybenzimidazole membranes (PBI). Of these membrane types, the poly-benzimidazole membrane, Celtec-L, exhibited the best combination of characteristics for use in an SDE. Several experimental membranes have also been analyzed including hydrated sulfonated Diels-Alder polyphenylenes (SDAPP) membranes from Sandia National Laboratory, perfluorosulfonimide (PFSI) and sulfonated perfluorocyclobutyl aromatic ether (S-PFCB) prepared by Clemson University, hydrated platinum-treated PFSA prepared by Giner Electrochemical Systems (GES) and Pt-Nafion{reg_sign} 115 composites prepared at SRNL. The chemical stability, SO{sub 2} transport and ionic conductivity characteristics have been measured for several commercially available and experimental proton-conducting membranes. Commercially available PFSA membranes such as the Nafion{reg_sign} series exhibited excellent chemical stability and ionic conductivity in sulfur dioxide saturated sulfuric acid solutions. Sulfur dioxide transport in the Nafion{reg_sign} membranes varied proportionally with the thickness and equivalent weight of the membrane. Although the SO{sub 2} transport in the Nafion{reg_sign} membranes is higher than desired, the excellent chemical stability and conductivity makes …
Date: September 1, 2008
Creator: Hobbs, D; Hector Colon-Mercado, H & Elvington, Mark C.
Object Type: Report
System: The UNT Digital Library
Validation of thermal models for a prototypical MEMS thermal actuator. (open access)

Validation of thermal models for a prototypical MEMS thermal actuator.

This report documents technical work performed to complete the ASC Level 2 Milestone 2841: validation of thermal models for a prototypical MEMS thermal actuator. This effort requires completion of the following task: the comparison between calculated and measured temperature profiles of a heated stationary microbeam in air. Such heated microbeams are prototypical structures in virtually all electrically driven microscale thermal actuators. This task is divided into four major subtasks. (1) Perform validation experiments on prototypical heated stationary microbeams in which material properties such as thermal conductivity and electrical resistivity are measured if not known and temperature profiles along the beams are measured as a function of electrical power and gas pressure. (2) Develop a noncontinuum gas-phase heat-transfer model for typical MEMS situations including effects such as temperature discontinuities at gas-solid interfaces across which heat is flowing, and incorporate this model into the ASC FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (3) Develop a noncontinuum solid-phase heat transfer model for typical MEMS situations including an effective thermal conductivity that depends on device geometry and grain size, and incorporate this model into the FEM heat-conduction code Calore to enable it to simulate these effects with …
Date: September 1, 2008
Creator: Gallis, Michail A.; Torczynski, John R.; Piekos, Edward Stanley; Serrano, Justin Raymond; Gorby, Allen D. & Phinney, Leslie Mary
Object Type: Report
System: The UNT Digital Library
Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 25, No. 7, Ed. 1 Monday, September 1, 2008 (open access)

Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 25, No. 7, Ed. 1 Monday, September 1, 2008

Monthly periodical from Oklahoma City, Oklahoma published by and for members of the Oklahoma State Firefighters Association that includes news and information along with advertising.
Date: September 1, 2008
Creator: Bain, Chris
Object Type: Journal/Magazine/Newsletter
System: The Gateway to Oklahoma History