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Reduction of pertechnetate by acetohydroxamic acid: Formation of [TcNO(AHA)2(H2O)]+ and implications for the UREX process. (open access)

Reduction of pertechnetate by acetohydroxamic acid: Formation of [TcNO(AHA)2(H2O)]+ and implications for the UREX process.

Reductive nitrosylation and complexation of ammonium pertechnetate by acetohydroxamic acid has been achieved in aqueous nitric and perchloric acid solutions. The kinetics of the reaction depend on the relative concentrations of the reaction components and are accelerated at higher temperatures. The reaction does not occur unless conditions are acidic. Analysis of the x-ray absorption fine structure spectroscopic data is consistent with a pseudo-octahedral geometry with the linear Tc-N-O bond typical of technetium nitrosyl compounds, and electron spin resonance spectroscopy is consistent with a the d{sup 5} Tc(II) nitrosyl complex. The nitrosyl source is generally AHA, but may be augmented by products of reaction with nitric acid. The resulting low-valency trans-aquonitrosyl(diacetohydroxamic)-technetium(II) complex (1) is highly soluble in water, extremely hydrophilic, and is not extracted by tri-n-butylphosphate in a dodecane diluent. Its extraction properties are not pH-dependent; titration studies indicate a single species from pH 4.5 down to -0.6 (calculated). This molecule is resistant to oxidation by H{sub 2}O{sub 2}, even at high pH, and can undergo substitution to form other technetium nitrosyl complexes. The formation of 1 may strongly impact the fate of technetium in the nuclear fuel cycle.
Date: February 26, 2008
Creator: 1Harry Reid Center for Environmental Studies, Nuclear Science and Technology Division, University of Nevada, Las Vegas, Las Vegas, NV, 89154-4006; Gong, Cynthia-May S; Poineau, Frederic; Lukens, Wayne W & Czerwinski, Kenneth R.
Object Type: Article
System: The UNT Digital Library
Technical Letter Report - Analysis of Ultrasonic Data on Piping Cracks at Ignalina Nuclear Power Plant Before and After Applying a Mechanical Stress Improvement Process, JCN-N6319, Task 2 (open access)

Technical Letter Report - Analysis of Ultrasonic Data on Piping Cracks at Ignalina Nuclear Power Plant Before and After Applying a Mechanical Stress Improvement Process, JCN-N6319, Task 2

Pacific Northwest National Laboratory (PNNL) is assisting the United States Nuclear Regulatory Commission (NRC) in developing a position on the management of primary water stress corrosion cracking (PWSCC) in piping systems previously analyzed for leak-before-break (LBB). Part of this work involves determining whether inspections alone are sufficient or if inspections plus mitigation techniques are needed. The work described in this report addresses the reliability of ultrasonic phased-array (PA) examinations for inspection of cracks that have been subjected to the mitigation method of mechanical stress improvement process (MSIP). It is believed that stresses imparted during MSIP may make ultrasonic crack responses in piping welds more difficult to detect and accurately characterize. To explore this issue, data were acquired, both before and after applying MSIP, and analyzed from cracked areas in piping at the Ignalina Nuclear Power Plant (INPP) in Lithuania. This work was performed under NRC Project JCN-N6319, PWSCC in Leak-Before-Break Systems.
Date: February 26, 2008
Creator: Anderson, Michael T.; Cumblidge, Stephen E. & Crawford, Susan L.
Object Type: Report
System: The UNT Digital Library
Perry Daily Journal (Perry, Okla.), Vol. 116, No. 40, Ed. 1 Tuesday, February 26, 2008 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 116, No. 40, Ed. 1 Tuesday, February 26, 2008

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: February 26, 2008
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 109, No. 230, Ed. 1 Tuesday, February 26, 2008 (open access)

The Altus Times (Altus, Okla.), Vol. 109, No. 230, Ed. 1 Tuesday, February 26, 2008

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 26, 2008
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Boerne Star (Boerne, Tex.), Vol. 102, No. 17, Ed. 1 Tuesday, February 26, 2008 (open access)

The Boerne Star (Boerne, Tex.), Vol. 102, No. 17, Ed. 1 Tuesday, February 26, 2008

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: February 26, 2008
Creator: Cartwright, Brian
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 88, No. 57, Ed. 1 Tuesday, February 26, 2008 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 88, No. 57, Ed. 1 Tuesday, February 26, 2008

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: February 26, 2008
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
The University News (Irving, Tex.), Vol. 38, No. 17, Ed. 1 Tuesday, February 26, 2008 (open access)

The University News (Irving, Tex.), Vol. 38, No. 17, Ed. 1 Tuesday, February 26, 2008

Weekly student newspaper from the University of Dallas in Irving, Texas that includes campus news and commentaries along with advertising.
Date: February 26, 2008
Creator: Crotty, Sarah
Object Type: Newspaper
System: The Portal to Texas History
Stochastic Hard-Sphere Dynamics for Hydrodynamics of Non-Ideal Fluids (open access)

Stochastic Hard-Sphere Dynamics for Hydrodynamics of Non-Ideal Fluids

A novel stochastic fluid model is proposed with a nonideal structure factor consistent with compressibility, and adjustable transport coefficients. This stochastic hard-sphere dynamics (SHSD) algorithm is a modification of the direct simulation Monte Carlo algorithm and has several computational advantages over event-driven hard-sphere molecular dynamics. Surprisingly, SHSD results in an equation of state and a pair correlation function identical to that of a deterministic Hamiltonian system of penetrable spheres interacting with linear core pair potentials. The fluctuating hydrodynamic behavior of the SHSD fluid is verified for the Brownian motion of a nanoparticle suspended in a compressible solvent.
Date: February 26, 2008
Creator: Donev, A; Alder, B J & Garcia, A L
Object Type: Article
System: The UNT Digital Library
Nanostructured Assemblies of Thermoelectric Composite Materials (open access)

Nanostructured Assemblies of Thermoelectric Composite Materials

At the end of the funding period (March 2003) for our program in ferroelectric oxide nanomaterials, we had 3 publications in print, one more had been submitted and two more were in preparation in peer-reviewed journals and invited symposia lectures had been given since starting the project in the Fall of 1999. We hired two postdoctoral fellows, Dr. Ki-Seog Chang and Dr. Wenzhong Wang. We have also trained two graduate students, Ms. Keri Williams and Ms. Bernadette Hernandez, and one undergraduate student (Mr. Michael Scancella).
Date: February 26, 2008
Creator: Dorhout, Peter K. & Fisher, Ellen R.
Object Type: Report
System: The UNT Digital Library

Guest Artist Recital: 2008-02-26 - Trio Amsterdam

Access: Use of this item is restricted to the UNT Community
Guest artist and faculty recital presented at the UNT College of Music Winspear Performance Hall.
Date: February 26, 2008
Creator: Egarr, Richard, 1963-; Mitchell, Mimi & Wentz, Jed
Object Type: Sound
System: The UNT Digital Library
Compound-Nuclear Reaction Cross Sections from Surrogate Measurements: Status and Challenges (open access)

Compound-Nuclear Reaction Cross Sections from Surrogate Measurements: Status and Challenges

None
Date: February 26, 2008
Creator: Escher, J.
Object Type: Article
System: The UNT Digital Library
Congressional Oversight and Related Issues Concerning the Prospective Security Agreement Between the United States and Iraq (open access)

Congressional Oversight and Related Issues Concerning the Prospective Security Agreement Between the United States and Iraq

This report provides information about the Congressional Oversight and Related Issues Concerning the Prospective Security Agreement Between the United States and Iraq.
Date: February 26, 2008
Creator: Garcia, Michael John; Mason, R. Chuck & Elsea, Jennifer K.
Object Type: Report
System: The UNT Digital Library
Evaluating EUV mask pattern imaging with two EUV microscopes (open access)

Evaluating EUV mask pattern imaging with two EUV microscopes

Aerial image measurement plays a key role in the development of patterned reticles for each generation of lithography. Studying the field transmitted (reflected) from EUV masks provides detailed information about potential disruptions caused by mask defects, and the performance of defect repair strategies, without the complications of photoresist imaging. Furthermore, by measuring the continuously varying intensity distribution instead of a thresholded, binary resist image, aerial image measurement can be used as feedback to improve mask and lithography system modeling methods. Interest in EUV, at-wavelength, aerial image measurement lead to the creation of several research tools worldwide. These tools are used in advanced mask development work, and in the evaluation of the need for commercial at-wavelength inspection tools. They describe performance measurements of two such tools, inspecting the same EUV mask in a series of benchmarking tests that includes brightfield and darkfield patterns. One tool is the SEMATECH Berkeley Actinic Inspection Tool (AIT) operating on a bending magnet beamline at Lawrence Berkeley National Laboratory's Advanced Light Source. The AIT features an EUV Fresnel zoneplate microscope that emulates the numerical aperture of a 0.25-NA stepper, and projects the aerial image directly onto a CCD camera, with 700x magnification. The second tool is …
Date: February 26, 2008
Creator: Goldberg, Kenneth A.; Takase, Kei; Naulleau, Patrick P.; Han, Hakseung; Barty, Anton; Kinoshita, Hiroo et al.
Object Type: Article
System: The UNT Digital Library

[Photograph of MAV members Derek Kerl and Patrick Partida]

Photograph of Men Against Violence members Derek Kerl and Patrick Partida standing next to each other, looking at the camera. They are both smiling.
Date: February 26, 2008
Creator: Ha, Khai
Object Type: Photograph
System: The UNT Digital Library
Congressional Budget Resolutions: Selected Statistics and Information Guide (open access)

Congressional Budget Resolutions: Selected Statistics and Information Guide

This report provides current and historical information on the budget resolution. It provides a list of the budget resolutions adopted and rejected by Congress since implementation of the Budget Act, including the U.S. Statutes-at-Large citations and committee report numbers, and describes their formulation and content. The report provides a table of selected optional components, a list of reconciliation measures, and information on the number of years covered by budget resolutions.
Date: February 26, 2008
Creator: Heniff, Bill, Jr. & Murray, Justin
Object Type: Report
System: The UNT Digital Library
Rains County Leader (Emory, Tex.), Vol. 120, No. 37, Ed. 1 Tuesday, February 26, 2008 (open access)

Rains County Leader (Emory, Tex.), Vol. 120, No. 37, Ed. 1 Tuesday, February 26, 2008

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: February 26, 2008
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iriduim and Gold (open access)

Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iriduim and Gold

We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from osmium (Z = 76) to gold (Z = 79). Of particular interest are the cross sections on Ir and Au including reactions on isomeric targets.
Date: February 26, 2008
Creator: Hoffman, R. D.; Dietrich, F. S.; Kelley, K.; Escher, J.; Bauer, R. & Mustafa, M. G.
Object Type: Report
System: The UNT Digital Library
Guam: U.S. Defense Deployments (open access)

Guam: U.S. Defense Deployments

This report mainly discusses about the U.S. Defense Deployments on Guam. The U.S military is building up forces on he U.S territory of Guam to maintain deterrence and war fighting capabilities for possible reason to disaster.
Date: February 26, 2008
Creator: Kan, Shirley A. & Niksch, Larry A.
Object Type: Report
System: The UNT Digital Library
Side-by-Side Comparison of Flood Insurance Reform Legislation in the 110th Congress (open access)

Side-by-Side Comparison of Flood Insurance Reform Legislation in the 110th Congress

This report discusses the key policy objectives of the National Flood Insurance Program (NFIP) that were threefold: (1) reduce the nation's flood risk through floodplain management; (2) improve flood hazard data and risk assessment by mapping the nation's floodplains; and (3) make affordable flood insurance widely available in communities that adopt and enforce measures to make future construction safer from flooding.
Date: February 26, 2008
Creator: King, Rawle O.
Object Type: Report
System: The UNT Digital Library
Grassroots Lobbying: Constitutionality of Disclosure Requirements (open access)

Grassroots Lobbying: Constitutionality of Disclosure Requirements

This report discusses the constitutional issues that may arise with respect to a federal law that would require disclosures of efforts to stimulate so-called "grassroots" lobbying activities by those entities and persons who are are compensated to engage in such activities.
Date: February 26, 2008
Creator: Maskell, Jack
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 93, No. 90, Ed. 1 Tuesday, February 26, 2008 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 93, No. 90, Ed. 1 Tuesday, February 26, 2008

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: February 26, 2008
Creator: Mattox, Jami
Object Type: Newspaper
System: The Gateway to Oklahoma History
Removal of Lattice Imperfections that Impact the Optical Quality of Ti:Sapphire using Advanced Magnetorheological Finishing Techniques (open access)

Removal of Lattice Imperfections that Impact the Optical Quality of Ti:Sapphire using Advanced Magnetorheological Finishing Techniques

Advanced magnetorheological finishing (MRF) techniques have been applied to Ti:sapphire crystals to compensate for sub-millimeter lattice distortions that occur during the crystal growing process. Precise optical corrections are made by imprinting topographical structure onto the crystal surfaces to cancel out the effects of the lattice distortion in the transmitted wavefront. This novel technique significantly improves the optical quality for crystals of this type and sets the stage for increasing the availability of high-quality large-aperture sapphire and Ti:sapphire optics in critical applications.
Date: February 26, 2008
Creator: Menapace, J. A.; Schaffers, K. I.; Bayramian, A. J.; Davis, P. J.; Ebbers, C. A.; Wolfe, J. E. et al.
Object Type: Article
System: The UNT Digital Library
National Aeronautics and Space Administration: Overview, FY2009 Budget, and Issues for Congress (open access)

National Aeronautics and Space Administration: Overview, FY2009 Budget, and Issues for Congress

This report discusses the budget of the fiscal year of 2009 and the requests of the National Aeronautics and Space Administration.
Date: February 26, 2008
Creator: Morgan, Daniel & Behrens, Carl E.
Object Type: Report
System: The UNT Digital Library
Thermal-Structural Analysis of the MacArthur Maze Freeway Collapse (open access)

Thermal-Structural Analysis of the MacArthur Maze Freeway Collapse

At approximately 3:41 AM on the morning of April 29, 2007, a tractor-trailer rig carrying 8,600 gallons (32.6 m{sup 3}) of fuel overturned on Interstate 880 in Oakland, CA. The resultant fire weakened the surrounding steel superstructure and caused a 50-yard (45.7 m) long section of the above connecting ramp from Interstate 80 to Interstate 580 to fail in approximately 18 minutes. In this study, we performed a loosely-coupled thermal-structural finite element analysis of the freeway using the LLNL Engineering codes NIKE3D, DYNA3D and TOPAZ3D. First, we applied an implicit structural code to statically initialize the stresses and displacements in the roadway at ambient conditions due to gravity loading. Next, we performed a thermal analysis by approximating the tanker fire as a moving box region of uniform temperature. This approach allowed for feasible calculation of the fire-to-structure radiative view factors and convective heat transport. We used a mass scaling methodology in the thermal analysis to reduce the overall simulation time so an explicit structural analysis could be used, which provided a more computationally efficient simulation of structural failure. Our approach showed structural failure of both spans due to thermal softening under gravity loading at approximately 20 minutes for a fixed …
Date: February 26, 2008
Creator: Noble, C. R.; Wemhoff, A. P. & McMichael, L. D.
Object Type: Article
System: The UNT Digital Library