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Recovering the Elemental Composition of Comet Wild 2 Dust in Five Stardust Impact Tracks and Terminal Particles in Aerogel (open access)

Recovering the Elemental Composition of Comet Wild 2 Dust in Five Stardust Impact Tracks and Terminal Particles in Aerogel

The elemental (non-volatile) composition of five Stardust impact tracks and terminal particles left from capture of Comet 81P/Wild 2 dust were mapped in a synchrotron x-ray scanning microprobe with full fluorescence spectra at each pixel. Because aerogel includes background levels of several elements of interest, we employ a novel 'dual threshold' approach to discriminate against background contaminants: an upper threshold, above which a spectrum contains cometary material plus aerogel and a lower threshold below which it contains only aerogel. The difference between normalized cometary-plus-background and background-only spectra is attributable to cometary material. The few spectra in between are discarded since misallocation is detrimental: cometary material incorrectly placed in the background spectrum is later subtracted from the cometary spectrum, doubling the loss of reportable cometary material. This approach improves precision of composition quantification. We present the refined whole impact track and terminal particle elemental abundances for the five impact tracks. One track shows mass increases in Cr and Mn (1.4x), Cu, As and K (2x), Zn (4x) and total mass (13%) by dual thresholds compared to a single threshold. Major elements Fe and Ni are not significantly affected. The additional Cr arises from cometary material containing little Fe. We exclude Au …
Date: January 4, 2007
Creator: Ishii, H. A.; Brennan, S.; Bradley, J. P.; Luening, K.; Ignatyev, K. & Pianetta, P.
Object Type: Article
System: The UNT Digital Library
Emergence of Strong Exchange Interaction in the Actinide Series: The Driving Force for Magnetic Stabilization of Curium (open access)

Emergence of Strong Exchange Interaction in the Actinide Series: The Driving Force for Magnetic Stabilization of Curium

Using electron energy-loss spectroscopy in a transmission electron microscope, many-electron atomic spectral calculations and density functional theory, we examine the electronic and magnetic structure of Cm metal. We show that angular momentum coupling in the 5f states plays a decisive role in the formation of the magnetic moment. The 5f states of Cm in intermediate coupling are strongly shifted towards the LS coupling limit due to exchange interaction, unlike most actinide elements where the effective spin-orbit interaction prevails. It is this LS-inclined intermediate coupling that is the key to producing the large spin polarization which in turn dictates the newly found crystal structure of Cm under pressure.
Date: January 4, 2007
Creator: Moore, K; der Laan, G v; Haire, D; Wall, M; Schwartz, A & Soderlind, P
Object Type: Article
System: The UNT Digital Library
Cleanup Verification Package for the 118-F-3, Minor Construction Burial Ground (open access)

Cleanup Verification Package for the 118-F-3, Minor Construction Burial Ground

This cleanup verification package documents completion of remedial action for the 118-F-3, Minor Construction Burial Ground waste site. This site was an open field covered with cobbles, with no vegetation growing on the surface. The site received irradiated reactor parts that were removed during conversion of the 105-F Reactor from the Liquid 3X to the Ball 3X Project safety systems and received mostly vertical safety rod thimbles and step plugs.
Date: January 4, 2007
Creator: Appel, M. J.
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 572, Ed. 1 Thursday, January 4, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 572, Ed. 1 Thursday, January 4, 2007

Free weekly newspaper that includes business and classified advertising.
Date: January 4, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 37, No. 573, Ed. 1 Thursday, January 4, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 573, Ed. 1 Thursday, January 4, 2007

Free weekly newspaper that includes business and classified advertising.
Date: January 4, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Texas Jewish Post (Fort Worth, Tex.), Vol. 61, No. 1, Ed. 1 Thursday, January 4, 2007 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 61, No. 1, Ed. 1 Thursday, January 4, 2007

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state and national news along with extensive advertising.
Date: January 4, 2007
Creator: Wisch, Rene
Object Type: Newspaper
System: The Portal to Texas History
The WTO, Intellectual Property Rights, and the Access to Medicines Controversy (open access)

The WTO, Intellectual Property Rights, and the Access to Medicines Controversy

This report discusses issues regarding a World Trade Organization (WTO) on the use of compulsory licenses by developing countries without manufacturing capacity to access life-sustaining medicines.
Date: January 4, 2007
Creator: Fergusson, Ian F.
Object Type: Report
System: The UNT Digital Library
Paperwork Reduction Act Reauthorization and Government Information Management Issues (open access)

Paperwork Reduction Act Reauthorization and Government Information Management Issues

None
Date: January 4, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The U.S.-Panama Free Trade Agreement (open access)

The U.S.-Panama Free Trade Agreement

None
Date: January 4, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 37, No. 1, Ed. 1 Thursday, January 4, 2007 (open access)

Port Aransas South Jetty (Port Aransas, Tex.), Vol. 37, No. 1, Ed. 1 Thursday, January 4, 2007

Weekly newspaper from Port Aransas, Texas on Mustang Island that includes local, state and national news along with extensive advertising.
Date: January 4, 2007
Creator: Judson, Mary Henkel
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 30, No. 269, Ed. 1 Thursday, January 4, 2007 (open access)

The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 30, No. 269, Ed. 1 Thursday, January 4, 2007

Free weekly newspaper that includes business and classified advertising.
Date: January 4, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Final Technical Report DE-FG02-03ER63576 (open access)

Final Technical Report DE-FG02-03ER63576

The magnetic resonance microscopy (MRM) work at Montana State University has provided unique data on transport in biofouled systems by imaging of biofilm structure and velocity in capillary and porous reactors. In poruos media non-invasive MRM directly measures length and time scale dependent dynamics. Our research demonstrates by direct measurement of the propagator, i.e. the displacement conditional probability or van Hove scattering function, the transition from normal to anomalous hydrodynamic dispersion as a function of bioactivity. The microbial activity transforms the porous media from a homogeneous to heterogeneous structure, increasing system complexity asdefined in terms of dynamics. Integration of these new data into model development for subsurface fate and transport of contaminants will be undertaken in future research.
Date: January 4, 2007
Creator: Seymour, Joseph D.
Object Type: Report
System: The UNT Digital Library
Final Removal Action Report of the CPP-603A Basin Facility (open access)

Final Removal Action Report of the CPP-603A Basin Facility

This Final Removal Action Report describes the actions that were taken under the non-time-critical removal action recommended in the Action Memorandum for the Non-Time Critical Removal Action at the CPP-603A Basins, Idaho Nuclear Technology and Engineering Center, as evaluated in the Engineering Evaluation/Cost Analysis for the CPP-603A Bason Non-Time Critical Removal Action, Idaho Nuclear Technology and Engineering Center. The Removal Action implemented consolidation and recording the location of debris objects containing radioactive cobalt (cobalt-60), removal and management of a small high-activity debris object (SHADO 1), the removal, treatment, and disposal of the basin water at the Idaho CERCLA Disposal Facility (ICDF) evaporation ponds, and filling the basins with grout/controlled low strength material.
Date: January 4, 2007
Creator: Croson, D. V.
Object Type: Report
System: The UNT Digital Library
JUSTIFICATION FOR A LIMIT OF 15 PERCENT HYDROGEN IN A 55 GALLON DRUM (open access)

JUSTIFICATION FOR A LIMIT OF 15 PERCENT HYDROGEN IN A 55 GALLON DRUM

The concentration of 15% hydrogen in air in a waste drum is used as the concentration at which the drum remains intact in the case of a deflagration. The following describes what could happen to the drum if 15% hydrogen or more in air were ignited. Table 2 of the Savannah River report WSRC-TR-90-165 ''TRU Drum Hydrogen Explosion Tests'' provides the results of tests performed in 55-gallon drums filled with hydrogen and air mixtures. The hydrogen-air mixtures were ignited by a hot-wire igniter. The results of the tests are shown in Table 1. They concluded that drums can withstand deflagration involving hydrogen concentration up to 15% hydrogen. Testing was performed at Idaho Falls and documented in a letter from RH Beers, Waste Technology Programs Division, EG&G Idaho, to CP Gertz, Radioactive Waste Technology Branch, DOE dated Sept. 29, 1983. In these tests, 55-gallon drums were filled with hydrogen-air mixtures which were ignited. The results in Table 2.2 showed that ignition for drums containing 11% and 14% hydrogen, the drum lid remained on the drum. Ignition in drum with 30% hydrogen resulted in lid loss. It is concluded from the results of these two tests that, for uncorroded drums, a 15% …
Date: January 4, 2007
Creator: MARUSICH, R.M.
Object Type: Report
System: The UNT Digital Library
An in-situ cell for characterization of solids by soft X-rayabsorption (open access)

An in-situ cell for characterization of solids by soft X-rayabsorption

An in-situ cell using ''lab-on-a-chip'' technologies has been designed and tested for characterization of catalysts and environmental materials using soft X-ray absorption spectroscopy and spectromicroscopy at photon energies above 250 eV. The sample compartment is 1.0 mm in diameter with a gas path length of 0.8 mm to minimize X-ray absorption in the gas phase. The sample compartment can be heated to 533 K by an Al resistive heater and gas flows up to 5.0 cm{sup 3} min{sup -1} can be supplied to the sample compartment through microchannels. The performance of the cell was tested by acquiring Cu L{sub 3}-edge XANES data during the reduction and oxidation of a silica-supported Cu catalyst using the beam line 11.0.2 Scanning Transmission X-ray Microscope (STXM) at the Advanced Light Source of LBNL. Two-dimensional images of individual catalyst particles were recorded at photon energies between 926 eV and 937 eV, the energy range in which the Cu(II) and Cu(I) L{sub 3} absorption edges are observed. Oxidation state specific images of the catalyst clearly show the disappearance of Cu(II) species during the exposure of the oxidized sample to 4% CO in He while increasing the temperature from 308 K to 473 K. Reoxidation restores the …
Date: January 4, 2007
Creator: Drake, Ian J.; Liu, Teris C.N.; Gilles, Mary; Tyliszczak, Tolek; Kilcoyne, A.L. David; Shuh, David K. et al.
Object Type: Article
System: The UNT Digital Library
Unregulated Contaminant Monitoring Regulation (UCMR) for Public Water Systems Revisions; Final Rule (open access)

Unregulated Contaminant Monitoring Regulation (UCMR) for Public Water Systems Revisions; Final Rule

Section of the Federal Register related to rules and regulations established by the U.S. Environmental Protection Agency (EPA) as of January 2007. This text addresses the final rule for 40 CFR parts 9, 141, and 142: Unregulated Contaminant Monitoring Regulation (UCMR) for Public Water Systems Revisions.
Date: January 4, 2007
Creator: United States. Office of the Federal Register.
Object Type: Text
System: The UNT Digital Library
Archer County News (Archer City, Tex.), No. 1, Ed. 1 Thursday, January 4, 2007 (open access)

Archer County News (Archer City, Tex.), No. 1, Ed. 1 Thursday, January 4, 2007

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date: January 4, 2007
Creator: Lewis, Shelley
Object Type: Newspaper
System: The Portal to Texas History
Polk County Enterprise (Livingston, Tex.), Vol. 125, No. 1, Ed. 1 Thursday, January 4, 2007 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 125, No. 1, Ed. 1 Thursday, January 4, 2007

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: January 4, 2007
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 22, No. 1, Ed. 1 Thursday, January 4, 2007 (open access)

Timpson & Tenaha News (Timpson, Tex.), Vol. 22, No. 1, Ed. 1 Thursday, January 4, 2007

Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date: January 4, 2007
Creator: Alexander, Nancy
Object Type: Newspaper
System: The Portal to Texas History
Comanche Chief (Comanche, Tex.), No. 36, Ed. 1 Thursday, January 4, 2007 (open access)

Comanche Chief (Comanche, Tex.), No. 36, Ed. 1 Thursday, January 4, 2007

Weekly newspaper from Comanche, Texas that includes local, state, and national news along with advertising.
Date: January 4, 2007
Creator: Wilkerson, James C., III
Object Type: Newspaper
System: The Portal to Texas History
The Odem-Edroy Times (Odem, Tex.), Vol. 61, No. 1, Ed. 1 Thursday, January 4, 2007 (open access)

The Odem-Edroy Times (Odem, Tex.), Vol. 61, No. 1, Ed. 1 Thursday, January 4, 2007

Weekly newspaper from Odem, Texas that includes local, state, and national news along with advertising.
Date: January 4, 2007
Creator: Tracy, Jimmy
Object Type: Newspaper
System: The Portal to Texas History
Hondo Anvil Herald (Hondo, Tex.), Vol. 121, No. 1, Ed. 1 Thursday, January 4, 2007 (open access)

Hondo Anvil Herald (Hondo, Tex.), Vol. 121, No. 1, Ed. 1 Thursday, January 4, 2007

Weekly newspaper from Hondo, Texas that includes local, state, and national news along with extensive advertising.
Date: January 4, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Sachse News (Sachse, Tex.), Vol. 2, No. 49, Ed. 1 Thursday, January 4, 2007 (open access)

The Sachse News (Sachse, Tex.), Vol. 2, No. 49, Ed. 1 Thursday, January 4, 2007

Weekly newspaper from Sachse, Texas that includes local, state and national news along with advertising.
Date: January 4, 2007
Creator: Fisher, Donnita Nesbit
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 39, Ed. 1 Thursday, January 4, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 39, Ed. 1 Thursday, January 4, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: January 4, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History