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Stabilizing and Rebuilding Iraq: U.S. Ministry Capacity Development Efforts Need an Overall Integrated Strategy to Guide Efforts and Manage Risk (open access)

Stabilizing and Rebuilding Iraq: U.S. Ministry Capacity Development Efforts Need an Overall Integrated Strategy to Guide Efforts and Manage Risk

A letter report issued by the Government Accountability Office with an abstract that begins "Iraq's ministries were decimated following years of neglect and centralized control under the former regime. Developing competent and loyal Iraqi ministries is critical to stabilizing and rebuilding Iraq. The President received $140 million in fiscal year 2007 funds and requested an additional $255 million in fiscal year 2008 to develop the capacity of the Iraq's ministries. This report assesses (1) the nature and extent of U.S. efforts to develop the capacity of the Iraqi ministries, (2) the key challenges to these efforts, and (3) the extent to which the U.S. government has an overall integrated strategy for these efforts. For this effort, GAO reviewed U.S. project contracts and reports and interviewed officials from the Departments of State (State), Defense (DOD), and the United States Agency for International Development (USAID) in Baghdad and Washington, D.C."
Date: October 1, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Financial Audit Manual: Volume 1, Exposure Draft, October 2007 (Superseded by GAO-08-585G) (open access)

Financial Audit Manual: Volume 1, Exposure Draft, October 2007 (Superseded by GAO-08-585G)

Guidance issued by the Government Accountability Office with an abstract that begins "This publication has been superseded by GAO-08-585G, Financial Audit Manual: Volume 1, July 2008. The U.S. Government Accountability Office (GAO) and the President's Council on Integrity and Efficiency (PCIE) maintain the GAO/PCIE Financial Audit Manual (FAM). The FAM provides guidance for performing financial statement audits of federal entities. The FAM is a key tool for enhancing accountability over taxpayer-provided resources."
Date: October 1, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Financial Audit Manual: Volume Two, Exposure Draft--October 2007 (Superseded by GAO-08-586G) (open access)

Financial Audit Manual: Volume Two, Exposure Draft--October 2007 (Superseded by GAO-08-586G)

Guidance issued by the Government Accountability Office with an abstract that begins "This publication has been superseded by GAO-08-586G, Financial Audit Manual: Volume 2, July 2008. The U.S. Government Accountability Office (GAO) and the President's Council on Integrity and Efficiency (PCIE) maintain the GAO/PCIE Financial Audit Manual (FAM). The FAM provides guidance for performing financial statement audits of federal entities. The FAM is a key tool for enhancing accountability over taxpayer-provided resources."
Date: October 1, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Shillapoo Wildlife Area, Annual Report 2007-2008. (open access)

Shillapoo Wildlife Area, Annual Report 2007-2008.

This report summarizes accomplishments, challenges and successes on WDFW's Shillapoo Wildlife Area funded under Bonneville Power Administration's (BPA) Wildlife Mitigation Program (BPA project No.2003-012-00) during the Fiscal Year 08 contract period October 1, 2007-September 30, 2008. The information presented here is intended to supplement that contained in BPA's PISCES contract development and reporting system. The organization below is by broad categories of work but references are made to individual work elements in the PISCES Statement of Work as appropriate. Significant progress was realized in almost all major work types. Of particular note was progress made in tree plantings and pasture rehabilitation efforts. This year's tree planting effort included five sites detailed below and in terms of the number of plants was certainly the largest effort on the wildlife area to date in one season. The planting itself took a significant amount of time, which was anticipated. However, installation of mats and tubes took much longer than expected which impacted planned fence projects in particular. Survival of the plantings appears to be good. Improvement to the quality of waterfowl pasture habitats is evident on a number of sites due to replanting and weed control efforts. Continuing long-term weed control efforts will …
Date: October 1, 2007
Creator: Calkins, Brian
Object Type: Report
System: The UNT Digital Library
Metagenomic and Functional Analysis of Hindgut Microbiota of a Wood-Feeding Higher Termite (open access)

Metagenomic and Functional Analysis of Hindgut Microbiota of a Wood-Feeding Higher Termite

From the standpoints of both basic research and biotechnology, there is considerable interest in reaching a clearer understanding of the diversity of biological mechanisms employed during lignocellulose degradation. Globally, termites are an extremely successful group of wood-degrading organisms and are therefore important both for their roles in carbon turnover in the environment and as potential sources of biochemical catalysts for efforts aimed at converting wood into biofuels. Only recently have data supported any direct role for the symbiotic bacteria in the gut of the termite in cellulose and xylan hydrolysis. Here we use a metagenomic analysis of the bacterial community resident in the hindgut paunch of a wood-feeding Nasutitermes species to show the presence of a large, diverse set of bacterial genes for cellulose and xylan hydrolysis. Many of these genes were expressed in vivo or had cellulase activity in vitro, and further analyses implicate spirochete and fibrobacter species in gut lignocellulose degradation. New insights into other important symbiotic functions including H{sub 2} metabolism, CO{sub 2}-reductive acetogenesis and N{sub 2} fixation are also provided by this first system-wide gene analysis of a microbial community specialized towards plant lignocellulose degradation. Our results underscore how complex even a 1-{micro}l environment can be.
Date: October 1, 2007
Creator: Warnecke, Falk; Warnecke, Falk; Luginbuhl, Peter; Ivanova, Natalia; Ghassemian, Majid; Richardson, Toby H. et al.
Object Type: Article
System: The UNT Digital Library
Syntheses, Structure, Magnetism, and Optical Properties of Lutetium-based Interlanthanide Selenides (open access)

Syntheses, Structure, Magnetism, and Optical Properties of Lutetium-based Interlanthanide Selenides

Ln{sub 3}LuSe{sub 6} (Ln = La, Ce), {beta}-LnLuSe{sub 3} (Ln = Pr, Nd), and Ln{sub x}Lu{sub 4-x}Se{sub 6} (Ln = Sm, Gd; x = 1.82, 1.87) have been synthesized using a Sb{sub 2}Se{sub 3} flux at 1000 C. Ln{sub 3}LuSe{sub 6} (Ln = La, Ce) adopt the U{sub 3}ScS{sub 6}-type three-dimensional structure, which is constructed from two-dimensional {infinity}{sup 2} [Ln{sub 3}Se{sub 6}]{sup 3-} slabs with the gaps between these slabs filled by octahedrally coordinated Lu{sup 3+} ions. The series of {beta}-LnLuSe{sub 3} (Ln = Pr, Nd) are isotypic with UFeS{sub 3}. Their structures include layers formed from LuSe6 octahedra that are separated by eight-coordinate larger Ln{sup 3+} ions in bicapped trigonal prismatic environments. Sm{sub 1.82}Lu{sub 2.18}Se{sub 6} and Gd{sub 1.87}Lu{sub 2.13}Se{sub 6} crystallize in the disordered F-Ln{sub 2}S{sub 3} type structure with the eight-coordinate bicapped trigonal prismatic Ln(1) ions residing in the one-dimensional channels formed by three different double chains via edge and corner sharing. These double chains are constructed from Ln(2)Se{sub 7} monocapped trigonal prisms, Ln(3)Se{sub 6} octahedra, and Ln(4)S{sub 6} octahedra, respectively. The magnetic susceptibilities of {beta}-PrLuSe{sub 3} and {beta}-NdLuSe{sub 3} follow the Curie-Weiss law. Sm{sub 1.82}Lu{sub 2.18}Se{sub 6} shows van Vleck paramagnetism. Magnetic measurements show that Gd{sub …
Date: October 1, 2007
Creator: Booth, Corwin H; Jin, Geng Bang; Choi, Eun Sang; Guertin, Robert P.; Brooks, James S.; Booth, Corwin H. et al.
Object Type: Article
System: The UNT Digital Library
Tevatron results on the discovery of sigma^(*)_b, b_s oscillations and the measurement of delta m_s, the lifetime difference delta gamma_s and the cp-violating phase phi (open access)

Tevatron results on the discovery of sigma^(*)_b, b_s oscillations and the measurement of delta m_s, the lifetime difference delta gamma_s and the cp-violating phase phi

The author discusses results from the Tevatron experiments on mixing and CP-violation in B{sub s} mesons, including the observation of B{sub s} oscillations and the first precision measurement of the mixing frequency, as well as a measurement of the lifetime difference {Delta}{Lambda}{sub s} and the first measurement of the CP-violating phase {delta}{sub s}. The author also briefly reports on the observation of four new bottom baryons at CDF.
Date: October 1, 2007
Creator: Heijboer, Aart
Object Type: Article
System: The UNT Digital Library
Idaho National Laboratory Cultural Resource Monitoring Report for Fiscal Year 2007 (open access)

Idaho National Laboratory Cultural Resource Monitoring Report for Fiscal Year 2007

This report describes the cultural resource monitoring activities of the Idaho National Laboratory’s (INL) Cultural Resource Management (CRM) Office during fiscal year 2007 (FY 2007). In FY 2007, 40 localities were revisited: two locations of heightened Shoshone-Bannock tribal sensitivity, four caves, three butte/craters, twelve prehistoric archaeological sites, two historic stage stations, nine historic homesteads, a portion of Goodale’s Cutoff of the Oregon Trail, a portion of historic trail T-16, one World War II dump, four buildings from the World War II period, and Experimental Breeder Reactor –I, a modern scientific facility and National Historic Landmark. Several INL project areas were also monitored in FY 2007. This included direct observation of ground disturbing activities within the Power Burst Facility (PBF, now designated as the Critical Infrastructure Test Range Complex – CITRC), backfilling operations associated with backhoe trenches along the Big Lost River, and geophysical surveys designed to pinpoint subsurface unexploded ordnance in the vicinity of the Naval Ordnance Disposal Area. Surprise checks were also made to three ongoing INL projects to ensure compliance with INL CRM Office recommendations to avoid impacts to cultural resources. Although some impacts were documented, no significant adverse effects that would threaten the National Register eligibility of …
Date: October 1, 2007
Creator: Pace, Brenda R.
Object Type: Report
System: The UNT Digital Library
Progress In High Temperature Electrolysis At The Idaho National Laboratory (open access)

Progress In High Temperature Electrolysis At The Idaho National Laboratory

The United States is considering the development of a domestic hydrogen-based energy economy. Hydrogen is of particular interest as a secondary energy carrier because it has the potential to be storable, transportable, environmentally benign, and useful in many chemical processes. Obviously, before a hydrogen economy can be implemented, an efficient and environmentally friendly means for large scale hydrogen production must be identified, proven, and developed. Hydrogen is now produced primarily via steam reforming of methane. However, from a long-term perspective, methane reforming is not a viable process for large-scale production of hydrogen since such fossil fuel conversion processes consume non-renewable resources and emit greenhouse gases. The U. S. National Research Council has recommended the use of water-splitting technologies to produce hydrogen using energy derived from a nuclear reactor. For the past several years, the Idaho National Laboratory has been actively studying the use of solid oxide fuel cells in conjunction with nuclear power for large-scale, high-temperature, electrolytic hydrogen production.
Date: October 1, 2007
Creator: Stoots, Carl M.; E.O'Brien, James; Herring, J. Steve & Hartvigsen, Joseph
Object Type: Article
System: The UNT Digital Library
Measuring the maturity of a technology : guidance on assigning a TRL. (open access)

Measuring the maturity of a technology : guidance on assigning a TRL.

This report provides guidance on how to assign a technology readiness level (TRL). The method proposed assists in assigning TRLs through a series of questions that focus on a set of unambiguous maturation metrics. This method is slightly biased towards the environment and approach to technology maturation at Sandia National Laboratories where customers and suppliers are in very close proximity to one another, allowing for supplier-customer interactions at a very early stage in technology development. The hope is that this report can serve as a practical guide to anyone trying to understand the maturity of a specific technology. Risk is reduced in system acquisition by selecting mature technologies for inclusion in system development. TRLs are used to assess the maturity of evolving technologies and therefore become part of an overall risk reduction strategy in system development.
Date: October 1, 2007
Creator: Mitchell, John Anthony
Object Type: Report
System: The UNT Digital Library
A search for z boson pair production at the Fermilab Tevatron Collider (open access)

A search for z boson pair production at the Fermilab Tevatron Collider

This dissertation describes a search for Z/{gamma}* boson pair production decaying into {mu}{mu}{mu}{mu}, {mu}{mu}ee, and eeee final states with approximately 1 fb{sup -1} of data at the Fermilab Tevatron Collider at {radical}s = 1.96 TeV. The small cross section times branching ratio for each channel mandated a thorough study of the acceptance and efficiencies. After optimization, 1.7 {+-} 0.1 events are expected for Standard Model production with a background of 0.13 {+-} 0.03 events. One event was found in the {mu}{mu}ee channel. A cross section limit of 4.4 pb is determined at a 95% confidence level for Standard Model production. Additionally, one parameter and two parameter 95% C.L. limits are found for the anomalous neutral trilinear gauge couplings ZZZ* and ZZ{gamma}*. The one parameter 95% C.L. coupling limits with a form factor scale of 1.2 TeV are: -0.28 < f{sub 40}{sup Z} < 0.28, -0.31 < f{sub 50}{sup Z} < 0.29, -0.26 < f{sub 40}{gamma} < 0.26, and -0.30 < f{sub 50}{sup {gamma}} < 0.28.
Date: October 1, 2007
Creator: Jarvis, Chad Ryan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Current Activities of the ASME Subgroup NUPACK (open access)

Current Activities of the ASME Subgroup NUPACK

Current activities of the American Society of Mechanical Engineers (ASME), Section III Subgroup on Containment Systems for Spent Fuel High-Level Waste Transport Packagings (also known as Subgroup NUPACK) are reviewed with emphasis on the recent revision of Subsection WB. Also, brief insightson new proposals for the development of rules for internal support structures and for a strain-based acceptance criteria are provided.
Date: October 1, 2007
Creator: Foster, Gerald M.; Morton, D. Keith & McConnell, Paul
Object Type: Article
System: The UNT Digital Library
Cell Phone Detection Techniques (open access)

Cell Phone Detection Techniques

A team composed of Rick Pratt, Dave Puczyki, Kyle Bunch, Ryan Slaugh, Morris Good, and Doug McMakin teamed together to attempt to exploit cellular telephone features and detect if a person was carrying a cellular telephone into a Limited Area. The cell phone’s electromagnetic properties were measured, analyzed, and tested in over 10 different ways to determine if an exploitable signature exists. The method that appears to have the most potential for success without adding an external tag is to measure the RF spectrum, not in the cell phone band, but between 240 and 400MHz. Figures 1- 7 show the detected signal levels from cell phones from three different manufacturers.
Date: October 1, 2007
Creator: Pratt, Richard M.; Bunch, Kyle J.; Puzycki, David J.; Slaugh, Ryan W.; Good, Morris S. & McMakin, Douglas L.
Object Type: Report
System: The UNT Digital Library
Alloys for advanced steam turbines--Oxidation behavior (open access)

Alloys for advanced steam turbines--Oxidation behavior

Advanced or ultra supercritical (USC) steam power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy (DOE) include power generation from coal at 60% efficiency, which would require steam temperatures of up to 760°C. Current research on the oxidation of candidate materials for advanced steam turbines is presented with a focus on a methodology for estimating chromium evaporation rates from protective chromia scales. The high velocities and pressures of advanced steam turbines lead to evaporation predictions as high as 5 × 10-8 kg m-2s-1 of CrO2(OH)2(g) at 760°C and 34.5 MPa. This is equivalent to 0.077 mm per year of solid Cr loss.
Date: October 1, 2007
Creator: Holcomb, G. R.
Object Type: Article
System: The UNT Digital Library
Mapping the geometry of the E6 group (open access)

Mapping the geometry of the E6 group

In this paper we present a construction for the compact form of the exceptional Lie group E{sub 6} by exponentiating the corresponding Lie algebra e{sub 6}, which we realize as the sum of f{sub 4}, the derivations of the exceptional Jordan algebra J{sub 3} of dimension 3 with octonionic entries, and the right multiplication by the elements of J{sub 3} with vanishing trace. Our parameterization is a generalization of the Euler angles for SU(2) and it is based on the fibration of E{sub 6} via a F{sub 4} subgroup as the fiber. It makes use of a similar construction we have performed in a previous article for F{sub 4}. An interesting first application of these results lies in the fact that we are able to determine an explicit expression for the Haar invariant measure on the E{sub 6} group manifold.
Date: October 1, 2007
Creator: Cerchiai , Bianca; Bernardoni, Fabio; Cacciatori, Sergio L.; Cerchiai, Bianca L. & Scotti, Antonio
Object Type: Article
System: The UNT Digital Library
Search for stop pairs in the emu channel (open access)

Search for stop pairs in the emu channel

The Standard Model gives a satisfying description of subatomic processes at low energy (< 1 TeV). Beyond this energy scale, other models must be considered. Supersymmetry is one of them. It gives in an elegant way, solutions to several Standard Model short comings. This document reports the search for a supersymmetric signal characterized by the production of two stops decaying into two b-jets, one electron, one muon and missing energy. This study has been performed at the D0 experiment, located on the ring of Tevatron collider at FermiLab, (Chicago, USA), whose energy in the center of mass reaches {radical}s = 1.96 TeV. The data used for this analysis have been collected during Run IIa of D0 detector; from april 2003 to march 2006 ({approx} 1fb{sup -1}). The objects handled for this analysis require a good understanding of both calorimeters, muon detectors and trackers. As Tevatron is an hadronic collider and the number of Standard Model processes with the same signature as the signal is low, the background is thus dominated by QCD processes. After the selection cuts, no excess of data has been observed with respect to the Standard Model expectation. D0 experiment sensibility has been improved and the 95% …
Date: October 1, 2007
Creator: Tissandier, Fabrice & U., /Clermont-Ferrand
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The mechanics of soft biological composites. (open access)

The mechanics of soft biological composites.

Biological tissues are uniquely structured materials with technologically appealing properties. Soft tissues such as skin, are constructed from a composite of strong fibrils and fluid-like matrix components. This was the first coordinated experimental/modeling project at Sandia or in the open literature to consider the mechanics of micromechanically-based anisotropy and viscoelasticity of soft biological tissues. We have exploited and applied Sandia's expertise in experimentation and mechanics modeling to better elucidate the behavior of collagen fibril-reinforced soft tissues. The purpose of this project was to provide a detailed understanding of the deformation of ocular tissues, specifically the highly structured skin-like tissue in the cornea. This discovery improved our knowledge of soft/complex materials testing and modeling. It also provided insight into the way that cornea tissue is bio-engineered such that under physiologically-relevant conditions it has a unique set of properties which enhance functionality. These results also provide insight into how non-physiologic loading conditions, such as corrective surgeries, may push the cornea outside of its natural design window, resulting in unexpected non-linear responses. Furthermore, this project created a clearer understanding of the mechanics of soft tissues that could lead to bio-inspired materials, such as highly supple and impact resistant body armor, and improve our …
Date: October 1, 2007
Creator: Nguyen, Thao D. (Sandia National Laboratories, Livermore, CA); Grazier, John Mark; Boyce, Brad Lee & Jones, Reese E. (Sandia National Laboratories, Livermore, CA)
Object Type: Report
System: The UNT Digital Library
Emittance growth scaling laws for crossing systematic space-charge driven sixth-order resonances and random octupole driven fourth-order resonances in FFAGs (open access)

Emittance growth scaling laws for crossing systematic space-charge driven sixth-order resonances and random octupole driven fourth-order resonances in FFAGs

None
Date: October 1, 2007
Creator: Pang, X.; Wang, F.; Wang, X.; Lee, S. Y. & Ng, K. Y.
Object Type: Report
System: The UNT Digital Library
MAPMT H7546B anode current response study for ILC SiD muon system prototype (open access)

MAPMT H7546B anode current response study for ILC SiD muon system prototype

The proposed Silicon Detector (SiD) concept for the ILC has barrel and end cap muon systems. An SiD scintillator based muon system prototype has 256 strips and was constructed from extruded strips, WLS fibers, clear fibers, and multianode photo multiplier tubes (MAPMT) Hamamatsu H7546B. Six MAPMTs were used. As a first step to understand strip output, the response of every anode to a given brightness of light and applied voltage must be measured. For the test, a custom made light source was used. Each MAPMT output was measured independently. The anode currents were measured at constant (green) input light brightness and the same photocathode to anode voltage (800V). The anode currents have a wide spread; for all tubes the maximum value is 5.23 times larger than the minimum value. The MAPMT cross talk was measured for one of the central inputs. The maximum cross talk value is about 4.9%. The average cross talk for the nearest four neighboring channels is 3.9%, for the farthest four is 1%. To assure the reproducibility and repeatability of the measurements, the double reference method was used.
Date: October 1, 2007
Creator: Dyshkant, A.; Blazey, G.; Francis, K.; Hedin, D.; Zutshi, V.; Fisk, H. et al.
Object Type: Article
System: The UNT Digital Library
Residual phase noise measurements of the input section in a receiver (open access)

Residual phase noise measurements of the input section in a receiver

If not designed properly, the input section of an analog down-converter can introduce phase noise that can prevail over other noise sources in the system. In the paper we present residual phase noise measurements of a simplified input section of a classical receiver that is composed of various commercially available mixers and driven by an LO amplifier.
Date: October 1, 2007
Creator: Mavric, Uros & Chase, Brian
Object Type: Article
System: The UNT Digital Library
Lifetime Difference and CP Asymmetry in the Bs -> J/psi phi decay (open access)

Lifetime Difference and CP Asymmetry in the Bs -> J/psi phi decay

The B{sub s} meson is an interesting particle to study because a sizable mixing induced CP violation in the B{sub s} -- {bar B}{sub s} system would be an indication for physics beyond the Standard Model. In this paper we present a measurement of the lifetime difference {Delta}{Gamma} between the B{sub s} mass eigenstates and the CP violating phase in the decay B{sub s} {yields} J/{psi}{phi}. In 1.7 fb{sup -1} of data collected with the CDF II detector at the Tevatron p{bar p} collider we measure {Delta}{Gamma} = 0.076{sup +0.059}{sub -0.063} (stat.) {+-}0.006 (syst.) ps{sup -1}, well consistent with the Standard Model prediction, and a mean B{sub s} lifetime of c{sub tau}{sub s} = 456 {+-} 13 (stat.) {+-} (syst.) {micro}m. We find no evidence for CP violation.
Date: October 1, 2007
Creator: Kuhr, Thomas
Object Type: Article
System: The UNT Digital Library
The CMS dataset bookkeeping service (open access)

The CMS dataset bookkeeping service

The CMS Dataset Bookkeeping Service (DBS) has been developed to catalog all CMS event data from Monte Carlo and Detector sources. It provides the ability to identify MC or trigger source, track data provenance, construct datasets for analysis, and discover interesting data. CMS requires processing and analysis activities at various service levels and the DBS system provides support for localized processing or private analysis, as well as global access for CMS users at large. Catalog entries can be moved among the various service levels with a simple set of migration tools, thus forming a loose federation of databases. DBS is available to CMS users via a Python API, Command Line, and a Discovery web page interfaces. The system is built as a multi-tier web application with Java servlets running under Tomcat, with connections via JDBC to Oracle or MySQL database backends. Clients connect to the service through HTTP or HTTPS with authentication provided by GRID certificates and authorization through VOMS. DBS is an integral part of the overall CMS Data Management and Workflow Management systems.
Date: October 1, 2007
Creator: Afaq, Anzar,; /Fermilab; Dolgert, Andrew; /Cornell U., Phys. Dept.; Guo, Yuyi; /Fermilab et al.
Object Type: Article
System: The UNT Digital Library
Visualization of Trajectories of Electron Beams Emitted by an IonSource with Closed Electron Drift (open access)

Visualization of Trajectories of Electron Beams Emitted by an IonSource with Closed Electron Drift

Trajectories of electron beams emitted by an ion source with an anode layer and Hall electron closed drift orbits were visualized using light emission from a working gas excited by electrons. Gas discharge of magnetron type, arising in the beam drift region under the influence of an electric field of a target bias potential, was visualized.
Date: October 1, 2007
Creator: Institue of Physics, National Academy of Sciences of Ukraine; Brown, Ian G.; Bordenjuk, Ian V.; Panchenko, Oleg A.; Sologub, Sergei V. & Brown, Ian G.
Object Type: Article
System: The UNT Digital Library
Measurement of tritium permeation in flibe (2LiF•BeF2) (open access)

Measurement of tritium permeation in flibe (2LiF•BeF2)

This paper reports on the experimental investigation of tritium permeation in flibe (2LiF-BeF2) at the Safety and Tritium Applied Research facility of the Idaho National Laboratory. A stainless steel cell formed by two independent volumes separated by a 2mm thick nickel membrane is maintained at temperatures between 500 and 700 degrees Celsius. A controlled amount of T2 gas is flown in excess of argon in the source volume in contact with the bottom side of the nickel membrane, while a layer of molten salt is in contact with the top side. The tritium permeating above the liquid surface is carried by an argon flow to a diagnostic system comprised of a quadrupole mass spectrometer, a gas chromatographer and a proportional counter. Tritium permeability in flibe as a function of temperature is determined by the measured permeation flow rates reached in steady-state conditions, while the diffusivity is determined by fitting the transient process with the analytical solution for the diffusion process. As a result, the solubility of tritium in flibe as a function of temperature is also determined.
Date: October 1, 2007
Creator: Calderoni, P.; Sharpe, P.; Hara, M. & Oya, Y.
Object Type: Article
System: The UNT Digital Library