3D Sedimentological and Geophysical Studies of Clastic Reservoir Analogs: Facies Architecture, Reservoir Properties, and Flow Behavior Within Delta Front Facies Elements of the Cretaceous Wall Creek Member, Frontier Formation, Wyoming (open access)

3D Sedimentological and Geophysical Studies of Clastic Reservoir Analogs: Facies Architecture, Reservoir Properties, and Flow Behavior Within Delta Front Facies Elements of the Cretaceous Wall Creek Member, Frontier Formation, Wyoming

Significant volumes of oil and gas occur in reservoirs formed by ancient river deltas. This has implications for the spatial distribution of rock types and the variation of transport properties. A between mudstones and sandstones may form baffles that influence productivity and recovery efficiency. Diagenetic processes such as compaction, dissolution, and cementation can also alter flow properties. A better understanding of these properties and improved methods will allow improved reservoir development planning and increased recovery of oil and gas from deltaic reservoirs. Surface exposures of ancient deltaic rocks provide a high-resolution view of variability. Insights gleaned from these exposures can be used to model analogous reservoirs, for which data is sparser. The Frontier Formation in central Wyoming provides an opportunity for high-resolution models. The same rocks exposed in the Tisdale anticline are productive in nearby oil fields. Kilometers of exposure are accessible, and bedding-plane exposures allow use of high-resolution ground-penetrating radar. This study combined geologic interpretations, maps, vertical sections, core data, and ground-penetrating radar to construct geostatistical and flow models. Strata-conforming grids were use to reproduce the observed geometries. A new Bayesian method integrates outcrop, core, and radar amplitude and phase data. The proposed method propagates measurement uncertainty and yields …
Date: December 21, 2009
Creator: White, Christopher D.
Object Type: Report
System: The UNT Digital Library
Bridging the Gap in the Chemical Thermodynamic Database for Nuclear Waste Repository: Studies of the Effect of Temperature on Actinide Complexation (open access)

Bridging the Gap in the Chemical Thermodynamic Database for Nuclear Waste Repository: Studies of the Effect of Temperature on Actinide Complexation

Recent results of thermodynamic studies on the complexation of actinides (UO{sub 2}{sup 2+}, NpO{sub 2}{sup +} and Pu{sup 4+}) with F{sup -}, SO{sub 4}{sup 2-} and H{sub 2}PO{sub 4}{sup -}/HPO{sub 4}{sup 2-} at elevated temperatures are reviewed. The data indicate that, for all systems except the 1:1 complexation of Np(V) with HPO{sub 4}{sup 2-}, the complexation of actinides is enhanced by the increase in temperature. The enhancement is primarily due to the increase in the entropy term (T{Delta}S) that exceeds the increase in the enthalpy ({Delta}H) as the temperature is increased. These data bridge the gaps in the chemical thermodynamic database for nuclear waste repository where the temperature could remain significantly higher than 25 C for a long time after the closure of the repository.
Date: December 21, 2009
Creator: Rao, Linfeng; Tian, Guoxin; Xia, Yuanxian; Friese, Judah I.; Zanonato, PierLuigi & Di Bernardo, Plinio
Object Type: Book
System: The UNT Digital Library
Curvature of the Lanthanide Contraction: An Explanation (open access)

Curvature of the Lanthanide Contraction: An Explanation

A number of studies have shown that for isostructural series of the lanthanides (elements La through Lu), a plot of equivalent metal-ligand bond lengths versus atomic number differs significantly from linearity and can be better fit as a quadratic equation. However, for hydrogen type wave functions, it is the inverse of the average distance of the electron from the nucleus (an estimate of size) that varies linearly with effective nuclear charge. This generates an apparent quadratic dependence of radius with atomic number. Plotting the inverse of lanthanide ion radii (the observed distance minus the ligand size) as a function of effective nuclear charge gives very good linear fits for a variety of lanthanide complexes and materials. Parameters obtained from this fit are in excellent agreement with the calculated Slater shielding constant, k.
Date: December 21, 2009
Creator: Raymond, Kenneth; Wellman, Daniel; Sgarlata, Carmelo & Hill, Aru
Object Type: Article
System: The UNT Digital Library
Dye Sensitized Tandem Photovoltaic Cells (open access)

Dye Sensitized Tandem Photovoltaic Cells

This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.
Date: December 21, 2009
Creator: Barber, Greg D.
Object Type: Report
System: The UNT Digital Library
Expected Performance of the LHC Synchrotron-Light Telescope (BSRT) and Abort-Gap Monitor (BSRA) (open access)

Expected Performance of the LHC Synchrotron-Light Telescope (BSRT) and Abort-Gap Monitor (BSRA)

This Report presents calculations of the synchrotron light from proton and lead-ion beams in the LHC at all energies from 0.45 to 7 TeV. It computes the emission from three sources: the uniform-field region of the D3 dipole, the dipole's edge field, and the short undulator just upstream. Light emitted at or near visible wavelengths is assessed for making optical measurements of transverse beam profiles and for monitoring the emptiness of the abort gap in the fill pattern. There is sufficient light for both applications, although both species pass through energy ranges in the ramp with small photon counts. Effects limiting image resolution are examined, including geometric optics, depth of field, and diffraction. The Report also considers recent suggestions that the undulator, intended to supplement the dipole for low energies, should not be ramped off at high energies and perhaps should not be used at all. We conclude that the undulator is essential at low energy for both species, but that it is possible to leave the undulator on at the cost of some blurring at intermediate energies.
Date: December 21, 2009
Creator: Fisher, Alan S.
Object Type: Report
System: The UNT Digital Library
Improving Corrosion Behavior in SCWR, LFR and VHTR Reactor Materials by Formation of a Stable Oxide (open access)

Improving Corrosion Behavior in SCWR, LFR and VHTR Reactor Materials by Formation of a Stable Oxide

The objective of this study is to understand the influence of the alloy microstructure and composition on the formation of a stable, protective oxide in the environments relevant to the SCWR and LFR reactor concepts, as well as to the VHTR. It is proposed to use state-of-the art techniques to study the fine structure of these oxides to identify the structural differences between stable and unstable oxide layers. The techniques to be used are microbeam synchrotron radiation diffraction and fluorescence, and cross-sectional transmission electron microcopy on samples prepared using focused ion beam.
Date: December 21, 2009
Creator: Motta, Arthur T.; Comstock, Robert; Li, Ning; Allen, Todd & Was, Gary
Object Type: Report
System: The UNT Digital Library
Metal-Air Electric Vehicle Battery: Sustainable, High-Energy Density, Low-Cost Electrochemical Energy Storage – Metal-Air Ionic Liquid (MAIL) Batteries (open access)

Metal-Air Electric Vehicle Battery: Sustainable, High-Energy Density, Low-Cost Electrochemical Energy Storage – Metal-Air Ionic Liquid (MAIL) Batteries

Broad Funding Opportunity Announcement Project: ASU is developing a new class of metal-air batteries. Metal-air batteries are promising for future generations of EVs because they use oxygen from the air as one of the battery’s main reactants, reducing the weight of the battery and freeing up more space to devote to energy storage than Li-Ion batteries. ASU technology uses Zinc as the active metal in the battery because it is more abundant and affordable than imported lithium. Metal-air batteries have long been considered impractical for EV applications because the water-based electrolytes inside would decompose the battery interior after just a few uses. Overcoming this traditional limitation, ASU’s new battery system could be both cheaper and safer than today’s Li-Ion batteries, store from 4-5 times more energy, and be recharged over 2,500 times.
Date: December 21, 2009
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Nuclear Recoil Cross Sections from Time-dependent Studies of Two-Photon Double Ionization of Helium (open access)

Nuclear Recoil Cross Sections from Time-dependent Studies of Two-Photon Double Ionization of Helium

We examine the sensitivity of nuclear recoil cross sections produced by two-photon double ionization of helium to the underlying triple differential cross sections (TDCS) used in their computation. We show that this sensitivity is greatest in the energy region just below the threshold for sequential double ionization. Accurate TDCS, extracted from non-perturbative solutions of the time-dependent Schroedinger equation, are used here in new computations of the nuclear recoil cross section.
Date: December 21, 2009
Creator: Horner, Daniel A.; Rescigno, Thomas N. & McCurdy, C. William
Object Type: Article
System: The UNT Digital Library
Products of the Benzene + O(3P) Reaction (open access)

Products of the Benzene + O(3P) Reaction

The gas-phase reaction of benzene with O(3P) is of considerable interest for modeling of aromatic oxidation, and also because there exist fundamental questions concerning the prominence of intersystem crossing in the reaction. While its overall rate constant has been studied extensively, there are still significant uncertainties in the product distribution. The reaction proceeds mainly through the addition of the O atom to benzene, forming an initial triplet diradical adduct, which can either dissociate to form the phenoxy radical and H atom, or undergo intersystem crossing onto a singlet surface, followed by a multiplicity of internal isomerizations, leading to several possible reaction products. In this work, we examined the product branching ratios of the reaction between benzene and O(3P) over the temperature range of 300 to 1000 K and pressure range of 1 to 10 Torr. The reactions were initiated by pulsed-laser photolysis of NO2 in the presence of benzene and helium buffer in a slow-flow reactor, and reaction products were identified by using the multiplexed chemical kinetics photoionization mass spectrometer operating at the Advanced Light Source (ALS) of Lawrence Berkeley National Laboratory. Phenol and phenoxy radical were detected and quantified. Cyclopentadiene and cyclopentadienyl radical were directly identified for the first …
Date: December 21, 2009
Creator: Taatjes, Craig A.; Osborn, David L.; Selby, Talitha M.; Meloni, Giovanni; Trevitt, Adam J.; Epifanovsky, Evgeny et al.
Object Type: Article
System: The UNT Digital Library
Rio Blanco, Colorado, Long-Term Hydrologic Monitoring Program Sampling and Analysis Results for 2009 (open access)

Rio Blanco, Colorado, Long-Term Hydrologic Monitoring Program Sampling and Analysis Results for 2009

The U.S. Department of Energy (DOE) Office of Legacy Management conducted annual sampling at the Rio Blanco, Colorado, Site, for the Long-Term Hydrologic Monitoring Program (LTHMP) on May 13 and 14, 2009. Samples were analyzed by the U.S. Environmental Protection Agency (EPA) Radiation&Indoor Environments National Laboratory in Las Vegas, Nevada. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectroscopy and tritium using the conventional and enriched methods.
Date: December 21, 2009
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Semantic-Aware Automatic Parallelization of Modern Applications Using High-Level Abstractions (open access)

Semantic-Aware Automatic Parallelization of Modern Applications Using High-Level Abstractions

Automatic introduction of OpenMP for sequential applications has attracted significant attention recently because of the proliferation of multicore processors and the simplicity of using OpenMP to express parallelism for shared-memory systems. However, most previous research has only focused on C and Fortran applications operating on primitive data types. Modern applications using high-level abstractions, such as C++ STL containers and complex user-defined class types, are largely ignored due to the lack of research compilers that are readily able to recognize high-level object-oriented abstractions and leverage their associated semantics. In this paper, we use a source-to-source compiler infrastructure, ROSE, to explore compiler techniques to recognize high-level abstractions and to exploit their semantics for automatic parallelization. Several representative parallelization candidate kernels are used to study semantic-aware parallelization strategies for high-level abstractions, combined with extended compiler analyses. Preliminary results have shown that semantics of abstractions can help extend the applicability of automatic parallelization to modern applications and expose more opportunities to take advantage of multicore processors.
Date: December 21, 2009
Creator: Liao, C; Quinlan, D J; Willcock, J J & Panas, T
Object Type: Article
System: The UNT Digital Library
Spectrophotometric and Calorimetric Studies of Np(V) Complexation with Acetate at Variable Temperatures (T = 283 - 343 K) (open access)

Spectrophotometric and Calorimetric Studies of Np(V) Complexation with Acetate at Variable Temperatures (T = 283 - 343 K)

Spectrophotometric titrations were performed to identify the Np(V)/acetate complex and determine the equilibrium constants at variable temperatures (T = 283 - 343 K) and at the ionic strength of 1.05 mol {center_dot} kg{sup -1}. The enthalpy of complexation at corresponding temperatures was determined by microcalorimetric titrations. Results show that the complexation of Np(V) with acetate is weak but strengthened as the temperature is increased. The complexation is endothermic and is entropy-driven. The enhancement of the complexation at elevated temperatures is primarily due to the increasingly larger entropy gain when the solvent molecules are released from the highly-ordered solvation spheres of NpO{sub 2}{sup +} and acetate to the bulk solvent where the degree of disorder is higher at higher temperatures.
Date: December 21, 2009
Creator: Rao, Linfeng; Tian, Guoxin; Srinivasan, Thandankorai G.; Zanonato, PierLuigi & Di Bernardo, Plinio
Object Type: Article
System: The UNT Digital Library
Spectroscopic signatures of proton transfer dynamics in the water dimer cation (open access)

Spectroscopic signatures of proton transfer dynamics in the water dimer cation

Using full dimensional EOM-IP-CCSD/aug-cc-pVTZ potential energy surfaces, the photoelectron spectrum, vibrational structure, and ionization dynamics of the water dimer radical cation, (H2O)+2, were computed. We also report an experimental photoelectron spectrum which is derived from photoionization efficiency measurements and compares favorably with the theoretical spectrum. The vibrational structure is also compared with the recent experimental work of Gardenier et al. [J. Phys. Chem. A 113, 4772 (2009)] and the recent theoretical calculations by Cheng et al. [J. Phys. Chem. A 113 13779 (2009)]. A reduced dimensionality nuclear Hamiltonian was used to compute the ionization dynamics for both the ground state and first excited state of the cation. The dynamics show markedly different behavior and spectroscopic signatures depending on which state of the cation is accessed by the ionization. Ionization to the ground-state cation surface induces a hydrogen transfer which is complete within 50 femtoseconds, whereas ionization to the first excited state results in a much slower process.
Date: December 21, 2009
Creator: Kamarchik, Eugene; Kostko, Oleg; Bowman, Joel M.; Ahmed, Musahid & Krylov, Anna I.
Object Type: Article
System: The UNT Digital Library
Symmetry, Optical Properties and Thermodynamics of Neptunium(V) Complexes (open access)

Symmetry, Optical Properties and Thermodynamics of Neptunium(V) Complexes

Recent results on the optical absorption and symmetry of the Np(V) complexes with dicarboxylate and diamide ligands are reviewed. The importance of recognizing the 'silent' feature of centrosymmetric Np(V) species in analyzing the absorption spectra and calculating the thermodynamic constants of Np(V) complexes is emphasized.
Date: December 21, 2009
Creator: Rao, Linfeng & Tian, Guoxin
Object Type: Article
System: The UNT Digital Library
An Innovative High Thermal Conductivity Fuel Design (open access)

An Innovative High Thermal Conductivity Fuel Design

Thermal conductivity of the fuel in today's Light Water Reactors, Uranium dioxide, can be improved by incorporating a uniformly distributed heat conducting network of a higher conductivity material, Silicon Carbide. The higher thermal conductivity of SiC along with its other prominent reactor-grade properties makes it a potential material to address some of the related issues when used in UO2 [97% TD]. This ongoing research, in collaboration with the University of Florida, aims to investigate the feasibility and develop a formal methodology of producing the resultant composite oxide fuel. Calculations of effective thermal conductivity of the new fuel as a function of %SiC for certain percentages and as a function of temperature are presented as a preliminary approach. The effective thermal conductivities are obtained at different temperatures from 600K to 1600K. The corresponding polynomial equations for the temperature-dependent thermal conductivities are given based on the simulation results. Heat transfer mechanism in this fuel is explained using a finite volume approach and validated against existing empirical models. FLUENT 6.1.22 was used for thermal conductivity calculations and to estimate reduction in centerline temperatures achievable within such a fuel rod. Later, computer codes COMBINE-PC and VENTURE-PC were deployed to estimate the fuel enrichment required, …
Date: November 21, 2009
Creator: Khan, Jamil A.
Object Type: Report
System: The UNT Digital Library
Major Successes of Theory-and-Experiment-Combined Studies in Surface Chemistry and Heterogeneous Catalysis. (open access)

Major Successes of Theory-and-Experiment-Combined Studies in Surface Chemistry and Heterogeneous Catalysis.

Experimental discoveries followed by theoretical interpretations that pave the way of further advances by experimentalists is a developing pattern in modern surface chemistry and catalysis. The revolution of modern surface science started with the development of surface-sensitive techniques such as LEED, XPS, AES, ISS and SIMS, in which the close collaboration between experimentalists and theorists led to the quantitative determination of surface structure and composition. The experimental discovery of the chemical activity of surface defects and the trends in the reactivity of transitional metals followed by the explanations from the theoretical studies led to the molecular level understanding of active sites in catalysis. The molecular level knowledge, in turn, provided a guide for experiments to search for new generation of catalysts. These and many other examples of successes in experiment-and-theory-combined studies demonstrate the importance of the collaboration between experimentalists and theorists in the development of modern surface science.
Date: November 21, 2009
Creator: Somorjai, Gabor A. & Li, Yimin
Object Type: Article
System: The UNT Digital Library
Characteristics of Energy Transport of Li-conditioned and non-Li-conditioned Plasmas in the National Spherical Torus Experiment (NSTX) (open access)

Characteristics of Energy Transport of Li-conditioned and non-Li-conditioned Plasmas in the National Spherical Torus Experiment (NSTX)

The transport properties of NSTX plasmas obtained during the 2008 experimental cam- paign have been studied and are reported here. Transport trends and dependences have been isolated, and it is found that both electron and ion energy transport coefficients have strong dependences on local values of nΔT, which in turn is strongly dependent on local current density profile. Without identifying this dependence, it is difficult to identify others, such as the dependence of transport coefficients on Bp (or q), Ip and Pheat. In addition, a comparison between discharges with and without Lithium wall conditioning has been made. While the trends in the two sets of data are similar, the thermal transport loss, especially in the electron channel, is found to strongly depend on the amount of Lithium deposited, decreasing by up to 50% of its no-Lithium value.
Date: October 21, 2009
Creator: S. Ding, S.M. Kaye, R.E. Bell, R. Kaita, H. Kugel, B.P. LeBlanc, S. Paul, B. Wan
Object Type: Report
System: The UNT Digital Library
EMSL Quarterly Highlights Report: FY09, 4th Quarter (open access)

EMSL Quarterly Highlights Report: FY09, 4th Quarter

This document describes the science, accomplishments, and publications that occurred during the fourth quarter of Fiscal Year 2009 at EMSL.
Date: October 21, 2009
Creator: Showalter, Mary Ann; Manke, Kristin L.; Kathmann, Loel E. & Wiley, Julie G.
Object Type: Report
System: The UNT Digital Library
Europium-doped barium bromide iodide (open access)

Europium-doped barium bromide iodide

Single crystals of Ba0.96Eu0.04BrI (barium europium bromide iodide) were grown by the Bridgman technique. The title compound adopts the ordered PbCl2 structure [Braekken (1932). Z. Kristallogr. 83, 222-282]. All atoms occupy the fourfold special positions (4c, site symmetry m) of the space group Pnma with a statistical distribution of Ba and Eu. They lie on the mirror planes, perpendicular to the b axis at y = +-0.25. Each cation is coordinated by nine anions in a tricapped trigonal prismatic arrangement.
Date: October 21, 2009
Creator: Gundiah, Gautam; Hanrahan, Stephen M.; Hollander, Fredrick J. & Bourret-Courchesne, Edith D.
Object Type: Article
System: The UNT Digital Library
Neutron Detector Gamma Insensitivity Criteria (open access)

Neutron Detector Gamma Insensitivity Criteria

The shortage of 3He has triggered the search for an effective alternative neutron detection technology for radiation portal monitor applications. Any new detection technology must satisfy two basic criteria: 1) it must meet the neutron detection efficiency requirement, and 2) it must be insensitive to gamma ray interference at a prescribed level, while still meeting the neutron detection requirement. It is the purpose of this document to define this latter criterion.
Date: October 21, 2009
Creator: Kouzes, Richard T.; Ely, James H.; Lintereur, Azaree T. & Stephens, Daniel L.
Object Type: Report
System: The UNT Digital Library
A SQUID-based microwave cavity search for dark-matter axions (open access)

A SQUID-based microwave cavity search for dark-matter axions

Axions in the {mu}eV mass range are a plausible cold dark matter candidate and may be detected by their conversion into microwave photons in a resonant cavity immersed in a static magnetic field. The first result from such an axion search using a superconducting first-stage amplifier (SQUID) is reported. The SQUID amplifier, replacing a conventional GaAs field-effect transistor amplifier, successfully reached axion-photon coupling sensitivity in the band set by present axion models and sets the stage for a definitive axion search utilizing near quantum-limited SQUID amplifiers.
Date: October 21, 2009
Creator: Asztalos, S. J.; Carosi, G.; Hagmann, C.; Kinion, D.; van Bibber, K.; Hotz, M. et al.
Object Type: Article
System: The UNT Digital Library
2008 Lawrence Livermore National Laboratory Annual Illness and Injury Surveillance Report (open access)

2008 Lawrence Livermore National Laboratory Annual Illness and Injury Surveillance Report

The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence of workdays, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: September 21, 2009
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
COG Software Architecture Design Description Document (open access)

COG Software Architecture Design Description Document

This COG Software Architecture Design Description Document describes the organization and functionality of the COG Multiparticle Monte Carlo Transport Code for radiation shielding and criticality calculations, at a level of detail suitable for guiding a new code developer in the maintenance and enhancement of COG. The intended audience also includes managers and scientists and engineers who wish to have a general knowledge of how the code works. This Document is not intended for end-users. This document covers the software implemented in the standard COG Version 10, as released through RSICC and IAEA. Software resources provided by other institutions will not be covered. This document presents the routines grouped by modules and in the order of the three processing phases. Some routines are used in multiple phases. The routine description is presented once - the first time the routine is referenced. Since this is presented at the level of detail for guiding a new code developer, only the routines invoked by another routine that are significant for the processing phase that is being detailed are presented. An index to all routines detailed is included. Tables for the primary data structures are also presented.
Date: September 21, 2009
Creator: Buck, R M & Lent, E M
Object Type: Report
System: The UNT Digital Library
Conceptual Engineering Method for Attenuating He Ion Interactions on First Wall Components in the Fusion Test Facility (FTF) Employing a Low-Pressure Noble Gas (open access)

Conceptual Engineering Method for Attenuating He Ion Interactions on First Wall Components in the Fusion Test Facility (FTF) Employing a Low-Pressure Noble Gas

It has been shown that post detonation energetic helium ions can drastically reduce the useful life of the (dry) first wall of an IFE reactor due to the accumulation of implanted helium. For the purpose of attenuating energetic helium ions from interacting with first wall components in the Fusion Test Facility (FTF) target chamber, several concepts have been advanced. These include magnetic intervention (MI), deployment of a dynamically moving first wall, use of a sacrificial shroud, designing the target chamber large enough to mitigate the damage caused by He ions on the target chamber wall, and the use of a low pressure noble gas resident in the target chamber during pulse power operations. It is proposed that employing a low-pressure (~ 1 torr equivalent) noble gas in the target chamber will thermalize energetic helium ions prior to interaction with the wall. The principle benefit of this concept is the simplicity of the design and the utilization of (modified) existing technologies for pumping and processing the noble ambient gas. Although the gas load in the system would be increased over other proposed methods, the use of a "gas shield" may provide a cost effective method of greatly extending the first wall …
Date: September 21, 2009
Creator: C.A.Gentile, W.R.Blanchard, T.Kozub, C.Priniski, I.Zatz, S.Obenschain
Object Type: Article
System: The UNT Digital Library