Remaining Sites Verification Package for the 100-F-26:12, 1.8-m (72-in.) Main Process Sewer Pipeline, Waste Site Reclassification Form 2007-034 (open access)

Remaining Sites Verification Package for the 100-F-26:12, 1.8-m (72-in.) Main Process Sewer Pipeline, Waste Site Reclassification Form 2007-034

The 100-F-26:12 waste site was an approximately 308-m-long, 1.8-m-diameter east-west-trending reinforced concrete pipe that joined the North Process Sewer Pipelines (100-F-26:1) and the South Process Pipelines (100-F-26:4) with the 1.8-m reactor cooling water effluent pipeline (100-F-19). In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: April 29, 2008
Creator: Capron, J. M.
Object Type: Report
System: The UNT Digital Library
Worldlines as Wilson Lines (open access)

Worldlines as Wilson Lines

Gravitational theories do not admit gauge invariant local operators. We study the limits under which there exists a quasi-local description for a class of non-local gravitational observables where a sum over worldlines plays the role of the Wilson line for gauge theory observables. We study non-local corrections to the local description and circumstances where these corrections become large. We find that these operators are quasi-local in at space and AdS, but fail to be quasi-local in de Sitter space.
Date: April 29, 2008
Creator: Green, Daniel & /SLAC /Stanford U., Dept. Phys.
Object Type: Article
System: The UNT Digital Library
Triple Differential Cross sections and Nuclear Recoil in Two-Photon Double Ionization of Helium (open access)

Triple Differential Cross sections and Nuclear Recoil in Two-Photon Double Ionization of Helium

Triple differential cross sections (TDCS) for two-photon double ionization of helium are calculated using the method of exterior complex scaling both above and below the threshold for sequential ionization (54.4 eV). It is found that sequential ionization produces characteristic behavior in the TDCS that identifies that process when it is in competition with nonsequential ionization. Moreover we see the signature in the TDCS and nuclear recoil cross sections of"virtual sequential ionization" below the threshold for the sequential process.
Date: April 29, 2008
Creator: Horner, Daniel A.; McCurdy, C. William & Rescigno, Thomas N
Object Type: Article
System: The UNT Digital Library
Modeling Light Capture Efficiency on Various Radiation Detector Geometries Using Monte-Carlo Optical Transport Software (open access)

Modeling Light Capture Efficiency on Various Radiation Detector Geometries Using Monte-Carlo Optical Transport Software

Investigates the optimization of light capture efficiency in a two scintillation cell radiation detector
Date: April 29, 2008
Creator: Jones, Sean E.; McIntyre, Justin I.; Cooper, Matthew W.; Keillor, Martin E.; Kiff, Scott D. & Tan, Hui
Object Type: Report
System: The UNT Digital Library
Final report: results of the 2007 targeted investigation at Hilton, Kansas. (open access)

Final report: results of the 2007 targeted investigation at Hilton, Kansas.

The Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), operated a grain storage facility in Hilton, Kansas, in 1954-1965. In 1992, carbon tetrachloride was first identified, at a concentration of 910 {micro}g/L, in groundwater from well GW01 at Hilton. This discovery occurred in association with the sale of the private grain storage facility on which well GW01 is located to the current owner, the Mid-Kansas Cooperative Association. The Kansas Department of Health and Environment conducted investigations at Hilton in 1992-1994. In 1996-1997, Argonne National Laboratory conducted Phase I and Phase II investigations on behalf of the CCC/USDA to characterize the distribution of the carbon tetrachloride contamination identified in well GW01, the stratigraphic units potentially hosting contaminant migration, and local hydrogeology in the Hilton area. The 2007 targeted investigation reported here focused specifically on the former CCC/USDA property at Hilton, west of the railroad tracks. (Until a property record search in 2005, the location of the CCC/USDA's former facility at Hilton was not known with certainty.) The objectives of the investigation, as implemented, were to (1) investigate for carbon tetrachloride contamination in the shallower soil and shallow aquifer units below the former CCC/USDA property and (2) …
Date: April 29, 2008
Creator: LaFreniere, L. M.
Object Type: Report
System: The UNT Digital Library
Mesure de l'angle Gamma du triangle d'unitarit_ de la matrice CKM dansles d_sint_grations B to D*K aupr_s de l'exp_rience BaBaR (open access)

Mesure de l'angle Gamma du triangle d'unitarit_ de la matrice CKM dansles d_sint_grations B to D*K aupr_s de l'exp_rience BaBaR

None
Date: April 29, 2008
Creator: Latour, Emmanuel & Polytechnique, /Ecole
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Dirac charge dynamics in graphene by infrared spectroscopy (open access)

Dirac charge dynamics in graphene by infrared spectroscopy

A remarkable manifestation of the quantum character of electrons in matter is offered by graphene, a single atomic layer of graphite. Unlike conventional solids where electrons are described with the Schrödinger equation, electronic excitations in graphene are governed by the Dirac hamiltonian. Some of the intriguing electronic properties of graphene, such as massless Dirac quasiparticles with linear energy-momentum dispersion, have been confirmed by recent observations. Here, we report an infrared spectromicroscopy study of charge dynamics in graphene integrated in gated devices. Our measurements verify the expected characteristics of graphene and, owing to the previously unattainable accuracy of infrared experiments, also uncover significant departures of the quasiparticle dynamics from predictions made for Dirac fermions in idealized, free-standing graphene. Several observations reported here indicate the relevance of many-body interactions to the electromagnetic response of graphene.
Date: April 29, 2008
Creator: Martin, Michael C.; Li, Z. Q.; Henriksen, E. A.; Jiang, Z.; Hao, Z.; Martin, Michael C et al.
Object Type: Article
System: The UNT Digital Library
A pulsed-laser calibration system for the laser backscatter diagnostics at the Omega laser (open access)

A pulsed-laser calibration system for the laser backscatter diagnostics at the Omega laser

A calibration system has been developed that allows a direct determination of the sensitivity of the laser backscatter diagnostics at the Omega laser. A motorized mirror at the target location redirects individual pulses of a mJ-class laser onto the diagnostic to allow the in-situ measurement of the local point response of the backscatter diagnostics. Featuring dual wavelength capability at the 2nd and 3rd harmonic of the Nd:YAG laser, both spectral channels of the backscatter diagnostics can be directly calibrated. In addition, channel cross-talk and polarization sensitivity can be determined. The calibration system has been employed repeatedly over the last two years and has enabled precise backscatter measurements of both stimulated Brillouin scattering and stimulated Raman scattering in gas-filled hohlraum targets that emulate conditions relevant to those in inertial confinement fusion targets.
Date: April 29, 2008
Creator: Neumayer, P.; Sorce, C.; Froula, D. H.; Rekow, V.; Loughman, K.; Knight, R. et al.
Object Type: Article
System: The UNT Digital Library
Electronic structure effects in liquid water studied by photoelectron spectroscopy and density functional theory (open access)

Electronic structure effects in liquid water studied by photoelectron spectroscopy and density functional theory

We present valence photoelectron emission spectra of liquid water in comparison with gas-phase water, ice close to the melting point, low temperature amorphous and crystalline ice. All aggregation states have major electronic structure changes relative to the free molecule, with rehybridization and development of bonding and anti-bonding states accompanying the hydrogen bond formation. Sensitivity to the local structural order, most prominent in the shape and splitting of the occupied 3a{sub 1} orbital, is understood from the electronic structure averaging over various geometrical structures, and reflects the local nature of the orbital interaction.
Date: April 29, 2008
Creator: Nordlund, Dennis; Odelius, Michael; Bluhm, Hendrik; Ogasawara, Hirohito; Pettersson, Lars G.M. & Nilsson, Anders
Object Type: Article
System: The UNT Digital Library
21st Century Locomotive Technology: Quarterly Technical Status Report 21 DOE/AL68284-TSR21 (open access)

21st Century Locomotive Technology: Quarterly Technical Status Report 21 DOE/AL68284-TSR21

Development of thermal analysis capabilities for a sodium metal halide battery system was initiated.
Date: April 29, 2008
Creator: Salasoo, Lembit
Object Type: Report
System: The UNT Digital Library
Repair of radiation-induced heat-labile sites is independent of DNA-PKcs, XRCC1 or PARP (open access)

Repair of radiation-induced heat-labile sites is independent of DNA-PKcs, XRCC1 or PARP

Ionizing radiation induces a variety of different DNA lesions: in addition to the most critical DNA damage, the DSB, numerous base alterations, SSBs and other modifications of the DNA double-helix are formed. When several non-DSB lesions are clustered within a short distance along DNA, or close to a DSB, they may interfere with the repair of DSBs and affect the measurement of DSB induction and repair. We have previously shown that a substantial fraction of DSBs measured by pulsed-field gel electrophoresis (PFGE) are in fact due to heat-labile sites (HLS) within clustered lesions, thus reflecting an artifact of preparation of genomic DNA at elevated temperature. To further characterize the influence of HLS on DSB induction and repair, four human cell lines (GM5758, GM7166, M059K, U-1810) with apparently normal DSB rejoining were tested for bi-phasic rejoining after gamma irradiation. When heat-released DSBs were excluded from the measurements the fraction of fast rejoining decreased to less than 50% of the total. However, neither the half-times of the fast (t{sub 1/2} = 7-8 min) or slow (t{sub 1/2} = 2.5 h) DSB rejoining were changed significantly. At t=0 the heat-released DSBs accounted for almost 40% of the DSBs, corresponding to 10 extra DSB/cell/Gy …
Date: April 29, 2008
Creator: Stenerlöw, Bo; Karlsson, Karin H.; Radulescu, Irina; Rydberg, Bjorn & Stenerlow, Bo
Object Type: Article
System: The UNT Digital Library