CHARACTERIZATION AND MONITORING OF NATURAL ATTENUATION OF CHLORINATED SOLVENTS IN GROUNDWATER: A SYSTEMS APPROACH (open access)

CHARACTERIZATION AND MONITORING OF NATURAL ATTENUATION OF CHLORINATED SOLVENTS IN GROUNDWATER: A SYSTEMS APPROACH

The objective of this document is to examine the use of a phased approach to characterizing and monitoring (C&M) natural attenuation processes and enhanced attenuation processes and to identify promising tools and techniques by which to accomplish the C&M. We will investigate developing techniques, such as molecular-based assessment tools, and existing tools that traditionally have not been used for monitoring the performance of environmental remediation technologies. Case studies will be used to provide examples of how non-traditional methods are being employed as characterization and monitoring tools to support MNA and EA. The document is not focused on a specific group of readers but rather is broadly directed with the intent that readers may gain information useful to their purposes. Thus, regulators may see some future characterization and monitoring techniques; end users may find novel ways to make MNA or EA more effective or efficient at their site; researchers may identify new areas for development or new and better combinations of existing methods. One consequence of this broad approach is that some readers may find certain sections either too rudimentary or too advanced for their needs. Hopefully, all will be able to use at least some of the document.
Date: August 10, 2006
Creator: Looney, B.; Michael Heitkamp, M.; Gary Wein (NOEMAIL), G.; Christopher Bagwell, C.; Karen Vangelas, K.; Karen-M Adams, K. et al.
Object Type: Report
System: The UNT Digital Library
An Automated Method to Quantify Radiation Damage in Human Blood Cells (open access)

An Automated Method to Quantify Radiation Damage in Human Blood Cells

Cytogenetic analysis of blood lymphocytes is a well established method to assess the absorbed dose in persons exposed to ionizing radiation. Because mature lymphocytes circulate throughout the body, the dose to these cells is believed to represent the average whole body exposure. Cytogenetic methods measure the incidence of structural aberrations in chromosomes as a means to quantify DNA damage which occurs when ionizing radiation interacts with human tissue. Methods to quantify DNA damage at the chromosomal level vary in complexity and tend to be laborious and time consuming. In a mass casualty scenario involving radiological/nuclear materials, the ability to rapidly triage individuals according to radiation dose is critically important. For high-throughput screening for dicentric chromosomes, many of the data collection steps can be optimized with motorized microscopes coupled to automated slide scanning platforms.
Date: July 10, 2006
Creator: Gordon K. Livingston, Mark S. Jenkins and Akio A. Awa
Object Type: Article
System: The UNT Digital Library
Modeling the QCD Equation of State in Relativistic Heavy Ion Collisions on BlueGene/L (open access)

Modeling the QCD Equation of State in Relativistic Heavy Ion Collisions on BlueGene/L

On 9,10 Feb 2006 a workshop was held at LLNL to discuss how a 10% allocation of the ASC BG/L supercomputer performing a finite temperature Lattice QCD (LQCD) calculation of the equation of state and non-equilibrium properties of the quark-gluon state of matter could lead to a breakthrough in our understanding of recent data from the Relativistic Heavy Ion Collider at Brookhaven National Lab. From this meeting and subsequent discussions we present a detailed plan for this calculation, including mechanisms for working in a secure computing environment and inserting the resulting equation of state into hydrodynamic transport models that will be compared directly to the RHIC data. We discuss expected benefits for DOE Office of Science research programs within the context of the NNSA mission.
Date: April 10, 2006
Creator: Soltz, R.; Grady, J.; Hartouni, E. P.; Gupta, R.; Vitev, I.; Mottola, E. et al.
Object Type: Report
System: The UNT Digital Library
CORROSION RESISTANCE OF STRUCTURAL AMORPHOUS METAL (open access)

CORROSION RESISTANCE OF STRUCTURAL AMORPHOUS METAL

Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoing corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The potential advantages of amorphous metals have been recognized for some time [Latanison 1985]. Iron-based corrosion-resistant, amorphous-metal coatings under development may prove important for maritime applications [Farmer et al. 2005]. Such materials could also be used to coat the entire outer surface of containers for the transportation and long-term storage of spent nuclear fuel, or to protect welds and heat affected zones, thereby preventing exposure to environments that might cause stress corrosion cracking [Farmer et al. 1991, 2000a, 2000b]. In the future, it may be possible to substitute such high-performance iron-based materials for more-expensive nickel-based alloys, thereby enabling cost savings in a wide variety of industrial applications. It should be noted that thermal-spray ceramic coatings have also been investigated for such applications [Haslam et al. 2005]. This …
Date: April 10, 2006
Creator: Lian, T; Day, S D & Farmer, J C
Object Type: Report
System: The UNT Digital Library
Environmental effects on the structure of metal ion-DOTA complexes: An ab initio study of radiopharmaceutical metals. (open access)

Environmental effects on the structure of metal ion-DOTA complexes: An ab initio study of radiopharmaceutical metals.

Quantum mechanical calculations were performed to study the differences between the important radiopharmaceutical metals yttrium (Y) and indium (In) bound by DOTA and modified DOTA molecules. Energies were calculated at the MP2/6-31+G(d)//HF/6-31G(d) levels, using effective core potentials on the Y and In ions. Although the minimum energy structures obtained are similar for both metal ion-DOTA complexes, changes in coordination and local environment significantly affect the geometries and energies of these complexes. Coordination by a single water molecule causes a change in the coordination number and a change in the position of the metal ion in In-DOTA; but, Y-DOTA is hardly affected by water coordination. When one of the DOTA carboxylates is replaced by an amide, the coordination energy for the amide arm shows a large variation between the Y and In ions. Optimizations including water and guandinium moieties to approximate the effects of antibody binding indicate a large energy cost for the DOTA-chelated In to adopt the ideal conformation for antibody binding.
Date: February 10, 2006
Creator: Lau, E. Y.; Lightstone, F. C. & Colvin, M. E.
Object Type: Article
System: The UNT Digital Library
Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: III. Emission Line Diagnostics of Ensembles of H II Regions (open access)

Modelling the Pan-Spectral Energy Distribution of Starburst Galaxies: III. Emission Line Diagnostics of Ensembles of H II Regions

We have built, as far as possible, fully self-consistent models of H II regions around aging clusters of stars. These produce strong emission line diagnostics applicable to either individual H II regions in galaxies, or to the integrated emission line spectra of disk or starburst galaxies. The models assume that the expansion and internal pressure of individual H II regions is driven by the net input of mechanical energy from the central cluster, be it through winds or supernova events. This eliminates the ionization parameter as a free variable, replacing it with a parameter which depends on the ratio of the cluster mass to the pressure in the surrounding interstellar medium. These models explain why H II regions with low abundances have high excitation, and demonstrate that at least part of the warm ionized medium is the result of overlapping faint, old, large, and low pressure H II regions. We present a number of line ratios (at both optical and IR wavelengths) that provide reliable abundance diagnostics for either single H II regions or for integrated galaxy spectra, and others that are sensitive to the age of the cluster stars exciting individual H II regions.
Date: May 10, 2006
Creator: Dopita, M A; Fischera, J; Sutherland, R S; Kewley, L J; Leitherer, C; Tuffs, R J et al.
Object Type: Article
System: The UNT Digital Library
Energetic feedback in galaxies: Processing of interstellar silicate grains by cosmic rays (open access)

Energetic feedback in galaxies: Processing of interstellar silicate grains by cosmic rays

The formation and evolution of stars and galaxies is a complex process that involves the cooling and collapse of dense interstellar clouds as well as energetic feedback on these clouds. Interstellar dust grains are central to the radiative transfer, thermal balance, and molecular processes in these clouds and can provide an important diagnostic. Hence, the effects of energetic processing of interstellar dust may have significant consequences. r This may be studied in our own Galaxy, where observations have shown that an appreciable fraction of silicates formed in the outflows from red giants and supergiants have a crystalline structure. Yet, the fraction of crystalline silicates in the interstellar medium is very small, pointing towards an efficient crystalline crystalline-to to-amorphous conversion process. Here we report experimental and modeling results that show that relatively ''low'' energy (0.1 - 5.0 GeV) heavy ion cosmic rays can rapidly ({approx}70 Million yrs) amorphize crystalline silicate grains ejected by stars into the interstellar medium. The implications of this are briefly discussed. We also examine the effects of cosmic ray processing of silicates in the solar system and in stellar debris disks. In the latter systems, cosmic ray processing may play a role for grains trapped in resonance …
Date: May 10, 2006
Creator: Bringa, E M; Kucheyev, S O; Loeffler, M J; Baragiola, R A; Tielens, A G W M; Dai, Z R et al.
Object Type: Article
System: The UNT Digital Library
Ground Truth, Magnitude Calibration and Regional Phase Propagation and Detection in the Middle East and Horn of Africa (open access)

Ground Truth, Magnitude Calibration and Regional Phase Propagation and Detection in the Middle East and Horn of Africa

In this project, we are exploiting unique and open source seismic data sets to improve seismic monitoring across the Middle East (including the Iranian Plateau, Zagros Mountains, Arabian Peninsula, Turkish Plateau, Gulf of Aqaba, Dead Sea Rift) and the Horn of Africa (including the northern part of the East African Rift, Afar Depression, southern Red Sea and Gulf of Aden). The data sets are being used to perform three related tasks. (1) We are determining moment tensors, moment magnitudes and source depths for regional events in the magnitude 3.0 to 6.0 range. (2) These events are being used to characterize high-frequency (0.5-16 Hz) regional phase attenuation and detection thresholds, especially from events in Iran recorded at stations across the Arabian Peninsula. (3) We are collecting location ground truth at GT5 (local) and GT20 (regional) levels for seismic events with M > 2.5, including source geometry information and source depths. In the first phase of this project, seismograms from earthquakes in the Zagros Mountains recorded at regional distances have been inverted for moment tensors, and source depths for the earthquakes have been determined via waveform matching. Early studies of the distribution of seismicity in the Zagros region found evidence for earthquakes …
Date: July 10, 2006
Creator: Nyblade, A.; Adams, A.; Brazier, R.; Park, Y. & Rodgers, A.
Object Type: Article
System: The UNT Digital Library
Data Analysis for Infiltration Modeling: Techical Evaluation of Previous Soil Depth Estimation Methods and Develoment of Aternate Parameter Values (open access)

Data Analysis for Infiltration Modeling: Techical Evaluation of Previous Soil Depth Estimation Methods and Develoment of Aternate Parameter Values

None
Date: July 10, 2006
Creator: Rehfeldt, K.
Object Type: Report
System: The UNT Digital Library
An Analysis of the X-Ray Diffraction Signal for the (alpha) - (epsilon) Transition in Shock-Compressed Iron: Simulation and Experiment (open access)

An Analysis of the X-Ray Diffraction Signal for the (alpha) - (epsilon) Transition in Shock-Compressed Iron: Simulation and Experiment

Recent published work has shown that the phase change of shock compressed iron along the [001] direction does transform to the {epsilon} (HCP) phase similar to the case for static measurements. This article provides an indepth analysis of the experiment and NEMD simulations, using x-ray diffraction in both cases to study the crystal structure upon transition. Both simulation and experiment are consistent with a compression and shuffle mechanism responsible for the phase change from BCC to HCP. Also both show a polycrystalline structure upon the phase transition, due to the four degenerate directions the phase change can occur on, with grain sizes measured of 4nm in the NEMD simulations and {approx} 2nm in the experiment. And looking at the time scale of the transition the NEMD shows the transition from the compressed BCC to HCP is less then 1.2 ps where the experimental data places an upper limit on the transition of 80 ps.
Date: April 10, 2006
Creator: Hawreliak, J; Colvin, J D; Kalantar, D H; Lorenzana, H E; Stolken, J S; Davies, H M et al.
Object Type: Article
System: The UNT Digital Library
Phenomenological Theory of the Photoevaporation Front Instability (open access)

Phenomenological Theory of the Photoevaporation Front Instability

The dynamics of photoevaporated molecular clouds is determined by the ablative pressure acting on the ionization front. An important step in the understanding of the ensuing motion is to develop the linear stability theory for the initially flat front. Despite the simplifications introduced by the linearization, the problem remains quite complex and still draws a lot of attention. The complexity is related to the large number of effects that have to be included in the analysis: acceleration of the front, possible temporal variation of the intensity of the ionizing radiation, the tilt of the radiation flux with respect to the normal to the surface, and partial absorption of the incident radiation in the ablated material. In this paper, we describe a model where all these effects can be taken into account simultaneously, and a relatively simple and universal dispersion relation can be obtained. The proposed phenomenological model may prove to be a helpful tool in assessing the feasibility of the laboratory experiments directed towards scaled modeling of astrophysical phenomena.
Date: April 10, 2006
Creator: Ryutov, D. D.; Kane, J. O.; Mizuta, A.; Pound, M. W. & Remington, B. A.
Object Type: Article
System: The UNT Digital Library
Environmental and Geometrical Conditions to Sustain Crevice Corrosion in Alloy 22 (open access)

Environmental and Geometrical Conditions to Sustain Crevice Corrosion in Alloy 22

Alloy 22 (N06022) is highly resistant to localized corrosion. Under aggressive environmental conditions Alloy 22 may be susceptible to crevice corrosion in hot chloride (Cl{sup -}) solutions. The objective of the present work was to explore the environmental and geometrical conditions for crevice corrosion to occur. Electrochemical tests were performed using PCA and prismatic mill annealed Alloy 22 specimens in chloride solutions. Crevice corrosion current density was found to be a function of applied potential. i{sub CREV} values ranged from 40 {micro}A/cm{sup 2} to 20 mA/cm{sup 2}. Such low values of current density explained the absence of pitting corrosion in Alloy 22 at any potential. Decreasing of the effective diffusion distance in a propagating crevice is thought to cause crevice corrosion stifling or repassivation after long anodic polarization. Crevice corrosion breakdown potential is expected to decrease with potential scan rate, approaching repassivation potential for low scan rates. The lowest corrosion potential of Alloy 22 in hydrochloric acid solutions at which active corrosion exists was proposed as the lowest possible repassivation potential for crevice corrosion.
Date: November 10, 2006
Creator: Carranza, R M; Rodr?guez, M A & Rebak, R B
Object Type: Article
System: The UNT Digital Library
Development of Structural Neurobiology and Genomics Programs in the Neurogenetic Institute (open access)

Development of Structural Neurobiology and Genomics Programs in the Neurogenetic Institute

The purpose of the DOE equipment-only grant was to purchase instrumentation in support of structural biology and genomics core facilities in the Zilkha Neurogenetic Institute (ZNI). The ZNI, a new laboratory facility (125,000 GSF) and a center of excellence at the Keck School of Medicine of USC, was opened in 2003. The goal of the ZNI is to recruit upwards of 30 new faculty investigators engaged in interdisciplinary research programs that will add breadth and depth to existing school strengths in neuroscience, epidemiology and genetics. Many of these faculty, and other faculty researchers at the Keck School will access structural biology and genomics facilities developed in the ZNI.
Date: November 10, 2006
Creator: Henderson, Brian E., M.D.
Object Type: Report
System: The UNT Digital Library
Incorporating Electrokinetic Phenomena into EBNavierStokes (open access)

Incorporating Electrokinetic Phenomena into EBNavierStokes

Motivated by the recent interest in using electrokinetic effects within microfluidic devices, they have extended the EBNavierStokes code to be able to handle electrokinetic effects. With this added functionality, the code becomes more useful for understanding and designing microfluidic devices that take advantage of electrokinetic effects (e.g. pumping and mixing). Supporting the simulation of electrokinetic effects required three main extensions to the existing code: (1) addition of an electric field solver, (2) development of a module for accurately computing the Smulochowski slip-velocity at fluid-solid boundaries, and (3) extension of the fluid solver to handle nonuniform inhomogeneous Dirichlet boundary conditions. The first and second extensions were needed to compute the electrokinetically generated slip-velocity at fluid-solid boundaries. The third extension made it possible for the fluid flow to be driven by a slip-velocity boundary condition (rather than by a pressure difference between inflow and outflow). In addition, several small changes were made throughout the code to make it compatible with these extensions. This report documents the changes to the EBNavierStokes code required to support the simulation of electrokinetic effects. They begin with a brief overview of the problem of electrokinetically driven flow. Next, they present a detailed description of the changes to …
Date: January 10, 2006
Creator: Chu, K & Trebotich, D
Object Type: Report
System: The UNT Digital Library
Enhanced Attenuation: A Reference Guide on Approaches to Increase the Natural Treatment Capacity of a System (open access)

Enhanced Attenuation: A Reference Guide on Approaches to Increase the Natural Treatment Capacity of a System

The objective of this document is to explore the realm of enhancements to natural attenuation processes for cVOCs and review examples that have been proposed, modeled, and implemented. We will identify lessons learned from these case studies to confirm that enhancements are technically feasible and have the potential to achieve a favorable, cost-effective contaminant mass balance. Furthermore, we hope to determine if opportunities for further improvement of the enhancements exist and suggest areas where new and innovative types of enhancements might be possible.
Date: August 10, 2006
Creator: Looney, B.; Michael Heitkamp, M.; Gary Wein (NOEMAIL), G.; Karen Vangelas, K.; Karen-M Adams, K.; Early, Tom et al.
Object Type: Report
System: The UNT Digital Library
A Comprehensive Theory of Yielding and Failure for Isotropic Materials (open access)

A Comprehensive Theory of Yielding and Failure for Isotropic Materials

A theory of yielding and failure for homogeneous and isotropic materials is given. The theory is calibrated by two independent, measurable properties and from those it predicts possible failure for any given state of stress. It also differentiates between ductile yielding and brittle failure. The explicit ductile-brittle criterion depends not only upon the material specification through the two properties, but also and equally importantly depends upon the type of imposed stress state. The Mises criterion is a special (limiting) case of the present theory. A close examination of this case shows that the Mises material idealization does not necessarily imply ductile behavior under all conditions, only under most conditions. When the first invariant of the yield/failure stress state is sufficiently large relative to the distortional part, brittle failure will be expected to occur. For general material types, it is shown that it is possible to have a state of spreading plastic flow, but as the elastic-plastic boundary advances, the conditions for yielding on it can change over to conditions for brittle failure because of the evolving stress state. The general theory is of a three dimensional form and it applies to full density materials for which the yield/failure strength in …
Date: August 10, 2006
Creator: Christensen, R M
Object Type: Article
System: The UNT Digital Library
Ultrabroadband 50-130 THz pulses generated via phase-matcheddifference frequency mixing in LiIO3 (open access)

Ultrabroadband 50-130 THz pulses generated via phase-matcheddifference frequency mixing in LiIO3

We report the generation of ultrabroadband pulses spanningthe 50-130 THz frequency range via phase-matched difference frequencymixing within the broad spectrum of sub-10 fs pulses in LiIO_3. Modelcalculations reproduce the octave-spanning spectra and predict few-cycleTHz pulse durations less than 20~;fs. The applicability of this scheme isdemonstrated with 9-fs pulses from a Ti:sapphire oscillator and with 7-fsamplified pulses from a hollow fiber compressor as pumpsources.
Date: October 10, 2006
Creator: Zentgraf, Thomas; Huber, Rupert; Nielsen, Nils C.; Chemla, DanielS. & Kaindl, Robert A.
Object Type: Article
System: The UNT Digital Library
Time-dependent Force-free Pulsar Magnetospheres: Axisymmetric and Oblique Rotators (open access)

Time-dependent Force-free Pulsar Magnetospheres: Axisymmetric and Oblique Rotators

Magnetospheres of many astrophysical objects can be accurately described by the low-inertia (or ''force-free'') limit of MHD. We present a new numerical method for solution of equations of force-free relativistic MHD based on the finite-difference time-domain (FDTD) approach with a prescription for handling spontaneous formation of current sheets. We use this method to study the time-dependent evolution of pulsar magnetospheres in both aligned and oblique magnetic geometries. For the aligned rotator we confirm the general properties of the time-independent solution of Contopoulos et al. (1999). For the oblique rotator we present the 3D structure of the magnetosphere and compute, for the first time, the spindown power of pulsars as a function of inclination of the magnetic axis. We find the pulsar spindown luminosity to be L {approx} ({mu}{sup 2}{Omega}{sub *}{sup 4}/c{sup 3})(1 + sin{sup 2}{alpha}) for a star with the dipole moment {mu}, rotation frequency {Omega}{sub *}, and magnetic inclination angle {alpha}. We also discuss the effects of current sheet resistivity and reconnection on the structure and evolution of the magnetosphere.
Date: April 10, 2006
Creator: Spitkovsky, Anatoly
Object Type: Report
System: The UNT Digital Library
First principles simulation of a superionic phase of hydrogen fluoride (HF) at high pressures and temperatures (open access)

First principles simulation of a superionic phase of hydrogen fluoride (HF) at high pressures and temperatures

The authors have conducted Ab initio molecular dynamics simulations of hydrogen fluoride (HF) at pressures of 5-66 GPa along the 900 K isotherm. They predict a superionic phase at 33 GPa, where the fluorine atoms are fixed in a bcc lattice while the hydrogen atoms diffuse rapidly with a diffusion constant of between 2 x 10{sup -5} and 5 x 10{sup -5} cm{sup 2}/s. They find that a transformation from asymmetric to symmetric hydrogen bonding occurs in HF at 66 GPa and 900 K. With superionic HF they have discovered a model system where symmetric hydrogen bonding occurs at experimentally achievable conditions. Given previous results on superionic H{sub 2}O[1,2,3] and NH{sub 3}[1], they conclude that high P,T superionic phases of electronegative element hydrides could be common.
Date: April 10, 2006
Creator: Goldman, N & Fried, L E
Object Type: Article
System: The UNT Digital Library
Pore Connectivity, Episodic Flow, and Unsaturated Diffusion in Fractured Tuff (open access)

Pore Connectivity, Episodic Flow, and Unsaturated Diffusion in Fractured Tuff

None
Date: November 10, 2006
Creator: Hu, Q; Ewing, R & Tomutsa, L
Object Type: Report
System: The UNT Digital Library
A Framework for the Analysis of Localized Corrosion at the Proposed Yucca Mountain Repository (open access)

A Framework for the Analysis of Localized Corrosion at the Proposed Yucca Mountain Repository

The proposed Repository presents a familiar materials performance application that is regularly encountered in energy, transportation and other industries. The widely accepted approach to dealing with materials performance is to identify the performance requirements, to determine the operating conditions to which materials will be exposed and to select materials of construction that perform well in those conditions. A special feature of the proposed Yucca Mountain Repository is the extremely long time frame of interest, i.e. 10,000's of years and longer. Thus, the time evolution of the environment in contact with waste package surfaces and the time evolution of corrosion damage that may result are of primary interest in the determination of expected performance. An approach is presented to the analysis of localized corrosion during a time period when it is possible for waters from drips and seepage to contact the waste package surfaces, and the analysis is demonstrated for the water chemistry of mixed salt solutions and a set of time-temperature-relative humidity profiles for a hot, mid and cool temperature waste package. Based on the analysis, there are large time periods when localized corrosion can not be supported, and no corrosion damage will occur. Further analysis can then focus on …
Date: January 10, 2006
Creator: Payer, J H; Carroll, S A; Gdowski, G E; Rebak, R B; Michels, T C; Miller, M C et al.
Object Type: Article
System: The UNT Digital Library
Cross-Roll Flow Forming of ODS Alloy Heat Exchanger Tubes For Hoop Creep Enhancement, Quarterly Technical Progress Report: October-December 2005 (open access)

Cross-Roll Flow Forming of ODS Alloy Heat Exchanger Tubes For Hoop Creep Enhancement, Quarterly Technical Progress Report: October-December 2005

Mechanically alloyed oxide dispersion strengthened (ODS) Fe-Cr-Al alloy thin walled tubes and sheets, produced via powder processing and consolidation methodologies, are promising materials for eventual use at temperatures up to 1200 C in the power generation industry, far above the temperature capabilities of conventional alloys. Target end-uses range from gas turbine combustor liners to high aspect ratio (L/D) heat exchanger tubes. Grain boundary creep processes at service temperatures, particularly those acting in the hoop direction, are the dominant failure mechanisms for such components. The processed microstructure of ODS alloys consists of high aspect ratio grains aligned parallel to the tube axis, a result of dominant axial metal flow which aligns the dispersoid particles and other impurities in the longitudinal direction. The dispersion distribution is unaltered on a micro scale by recrystallization thermal treatments, but the high aspect ratio grain shape typically obtained limits transverse grain spacing and consequently the hoop creep response. Improving hoop creep in ODS-alloy components will require understanding and manipulating the factors that control the recrystallization behavior, and represents a critical materials design and development challenge that must be overcome in order to fully exploit the potential of ODS alloys. The objectives of this program are to …
Date: April 10, 2006
Creator: Kad, Bimal K.
Object Type: Report
System: The UNT Digital Library

Renewable Energy: Poised to Realize Long-Term Potential

None
Date: June 10, 2006
Creator: Arvizu, D.
Object Type: Presentation
System: The UNT Digital Library
Surveillance of Site A and Plot M - Report for 2005. (open access)

Surveillance of Site A and Plot M - Report for 2005.

The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for Calendar Year 2005 are presented. Based on the results of the 1976-1978 radiological characterization of the site, a determination was made that a surveillance program be established. The characterization study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby handpumped picnic wells. The current surveillance program began in 1980 and consists of sample collection and analysis of surface and subsurface water. The results of the analyses are used to (1) monitor the migration pathway of water from the burial ground (Plot M) to the handpumped picnic wells, (2) establish if buried radionuclides other than hydrogen-3 have migrated, and (3) monitor the presence of radioactive and chemically hazardous materials in the environment of the area. Hydrogen-3 in the Red Gate Woods picnic wells was still detected this year, but the average and maximum concentrations were significantly less than found earlier. Hydrogen-3 continues to be detected in a number of wells, boreholes, dolomite holes, and a surface stream. Analyses since 1984 have indicated the presence of low levels of strontium-90 …
Date: April 10, 2006
Creator: Golchert, N. W. & Oversight, ESH /QA
Object Type: Report
System: The UNT Digital Library