EVALUATION OF TEMPORAL VARIATIONS IN HYDRAULIC CAPTURE DUE TO CHANGING FLOW PATTERNS USING MAPPING AND MODELING TECHNIQUES (open access)

EVALUATION OF TEMPORAL VARIATIONS IN HYDRAULIC CAPTURE DUE TO CHANGING FLOW PATTERNS USING MAPPING AND MODELING TECHNIQUES

Robust performance evaluation represents one of the most challenging aspects of groundwater pump-and-treat (P&T) remedy implementation. In most cases, the primary goal of the P&T system is hydraulic containment, and ultimately recovery, of contaminants to protect downgradient receptors. Estimating the extent of hydraulic containment is particularly challenging under changing flow patterns due to variable pumping, boundaries and/or other conditions. We present a systematic approach to estimate hydraulic containment using multiple lines of evidence based on (a) water-level mapping and (b) groundwater modeling. Capture Frequency Maps (CFMs) are developed by particle tracking on water-level maps developed for each available water level data set using universal kriging. In a similar manner, Capture Efficiency Maps (CEMs) are developed by particle tracking on water-levels calculated using a transient groundwater flow model: tracking is undertaken independently for each stress period using a very low effective porosity, depicting the 'instantaneous' fate of each particle each stress period. Although conceptually similar, the two methods differ in their underlying assumptions and their limitations: their use together identifies areas where containment may be reliable (i.e., where the methods are in agreement) and where containment is uncertain (typically, where the methods disagree). A field-scale example is presented to illustrate these …
Date: April 7, 2011
Creator: AA, SPILIOTOPOULOS; LC, SWANSON; R, SHANNON & MJ, TONKIN
Object Type: Article
System: The UNT Digital Library
Search for the Rare Radiative Decay: $W\rightarrow\pi\gamma$ in $p\bar{p}$ Collisions at $\sqrt{s} = 1.96$ TeV (open access)

Search for the Rare Radiative Decay: $W\rightarrow\pi\gamma$ in $p\bar{p}$ Collisions at $\sqrt{s} = 1.96$ TeV

We present a search for the rare radiative decay W{sup {+-}} {yields} {pi}{sup {+-}}{gamma} using data corresponding to an integrated luminosity of 4.3 fb{sup -1} of proton-antiproton collisions at a center of mass energy of 1.96 TeV collected by the CDF experiment at Fermilab. As no statistically significant signal is observed, we set a 95% confidence level upper limit on the relative branching fraction {Gamma}(W{sup {+-}} {yields} {pi}{sup {+-}}{gamma})/{Gamma}(W{sup {+-}} {yields} e{sup {+-}}{nu}) at 6.4 x 10{sup -5}, a factor of 10 improvement over the previous limit.
Date: April 1, 2011
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Alvarez Gonzalez, B.; Phys., /Oviedo U. /Cantabria Inst. of; Amerio, S.; /INFN, Padua et al.
Object Type: Article
System: The UNT Digital Library
Hybrid Organic-Inorganic Composite Solar Cells for Efficient, Low Cost, Photoelectric Energy Conversion (open access)

Hybrid Organic-Inorganic Composite Solar Cells for Efficient, Low Cost, Photoelectric Energy Conversion

Cadmium selenide nanoparticles and nanoclusters were prepared and added to polymer solar cells to improve their photon capture ability. These nanoparticles did exhibit some beneficial effects on the photon conversion efficiencies of selected polymer solar cells. Ternary bulk heterojunction systems based on composites of methyl viologen-doped, CdSe nanoparticles blended with poly (3-hexothiopene) (P3HT) and 6, 6-phenyl C{sub 61}-butyric acid methyl ester (PCBM) were also tested. It was found that the devices with methyl viologen-doped CdSe nanoparticles do produce more photocurrent in a region surrounding the absorption peak of the particles (560 to 660nm) when compared to pristine P3HT:PCBM devices. Gold nanorods were also prepared and tested in some solar cells. These nanorods did produce a very small enhancement in photon absorbance, but the observed increase the photon conversion efficiency was not sufficient to make the effort worthwhile. Our goals were (1) to prepare cadmium sulfide and cadmium selenide clusters and nanoparticles to be tested as photon absorbers to enhance the photon conversion efficiency of polymer solar polymer solar cells and (2) to prepare gold and silver nanorods to be added to polymer solar cells to enhance their photon capture capability. The cadmium sulfide and cadmium selenide nanoparticles and some new …
Date: April 6, 2011
Creator: Adams, Richard D.
Object Type: Report
System: The UNT Digital Library
CONFIRMATORY SURVEY RESULTS FOR PORTIONS OF THE MATERIALS AND EQUIPMENT FROM UNITS 1 AND 2 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA (open access)

CONFIRMATORY SURVEY RESULTS FOR PORTIONS OF THE MATERIALS AND EQUIPMENT FROM UNITS 1 AND 2 AT THE HUMBOLDT BAY POWER PLANT, EUREKA, CALIFORNIA

The Pacific Gas & Electric Company (PG&E) operated the Humboldt Bay Power Plant (HBPP) Unit 3 nuclear reactor near Eureka, California under Atomic Energy Commission (AEC) provisional license number DPR-7. HBPP Unit 3 achieved initial criticality in February 1963 and began commercial operations in August 1963. Unit 3 was a natural circulation boiling water reactor with a direct-cycle design. This design eliminated the need for heat transfer loops and large containment structures. Also, the pressure suppression containment design permitted below-ground construction. Stainless steel fuel claddings were used from startup until cladding failures resulted in plant system contamination—zircaloy-clad fuel was used exclusively starting in 1965 eliminating cladding-related contamination. A number of spills and gaseous releases were reported during operations resulting in a range of mitigative activities (see ESI 2008 for details).
Date: April 1, 2011
Creator: Adams, W. C.
Object Type: Report
System: The UNT Digital Library
Monte Carlo Simulations of Cosmic Rays Hadronic Interactions (open access)

Monte Carlo Simulations of Cosmic Rays Hadronic Interactions

This document describes the construction and results of the MaCoR software tool, developed to model the hadronic interactions of cosmic rays with different geometries of materials. The ubiquity of cosmic radiation in the environment results in the activation of stable isotopes, referred to as cosmogenic activities. The objective is to use this application in conjunction with a model of the MAJORANA DEMONSTRATOR components, from extraction to deployment, to evaluate cosmogenic activation of such components before and after deployment. The cosmic ray showers include several types of particles with a wide range of energy (MeV to GeV). It is infeasible to compute an exact result with a deterministic algorithm for this problem; Monte Carlo simulations are a more suitable approach to model cosmic ray hadronic interactions. In order to validate the results generated by the application, a test comparing experimental muon flux measurements and those predicted by the application is presented. The experimental and simulated results have a deviation of 3%.
Date: April 1, 2011
Creator: Aguayo Navarrete, Estanislao; Orrell, John L. & Kouzes, Richard T.
Object Type: Report
System: The UNT Digital Library
Fast timing detectors for forward protons at the LHC (open access)

Fast timing detectors for forward protons at the LHC

The author discusses the development of high precision timing detectors for high momentum protons at the LHC, and their application in studying exclusive Higgs boson production.
Date: April 1, 2011
Creator: Albrow, Michael
Object Type: Article
System: The UNT Digital Library
DISTRIBUTION COEFICIENTS (KD) GENERATED FROM A CORE SAMPLE COLLECTED FROM THE SALTSTONE DISPOSAL FACILITY (open access)

DISTRIBUTION COEFICIENTS (KD) GENERATED FROM A CORE SAMPLE COLLECTED FROM THE SALTSTONE DISPOSAL FACILITY

Core samples originating from Vault 4, Cell E of the Saltstone Disposal Facility (SDF) were collected in September of 2008 (Hansen and Crawford 2009, Smith 2008) and sent to SRNL to measure chemical and physical properties of the material including visual uniformity, mineralogy, microstructure, density, porosity, distribution coefficients (K{sub d}), and chemical composition. Some data from these experiments have been reported (Cozzi and Duncan 2010). In this study, leaching experiments were conducted with a single core sample under conditions that are representative of saltstone performance. In separate experiments, reducing and oxidizing environments were targeted to obtain solubility and Kd values from the measurable species identified in the solid and aqueous leachate. This study was designed to provide insight into how readily species immobilized in saltstone will leach from the saltstone under oxidizing conditions simulating the edge of a saltstone monolith and under reducing conditions, targeting conditions within the saltstone monolith. Core samples were taken from saltstone poured in December of 2007 giving a cure time of nine months in the cell and a total of thirty months before leaching experiments began in June 2010. The saltstone from Vault 4, Cell E is comprised of blast furnace slag, class F fly …
Date: April 25, 2011
Creator: Almond, P. & Kaplan, D.
Object Type: Report
System: The UNT Digital Library
Making Stuff Outreach at the Ames Laboratory and Iowa State University (open access)

Making Stuff Outreach at the Ames Laboratory and Iowa State University

The U. S. Department of Energy's Ames Laboratory in Ames, Iowa was a coalition partner for outreach activities connected with NOVA's Making Stuff television series on PBS. Volunteers affiliated with the Ames Laboratory and Iowa State University, with backgrounds in materials science, took part in activities including a science-themed Family Night at a local mall, Science Cafes at the Science Center of Iowa, teacher workshops, demonstrations at science nights in elementary and middle schools, and various other events. We describe a selection of the activities and present a summary of their outcomes and extent of their impact on Ames, Des Moines and the surrounding communities in Iowa. In Part 2, results of a volunteer attitude survey are presented, which shed some light on the volunteer experience and show how the volunteers participation in outreach activities has affected their views of materials education.
Date: April 1, 2011
Creator: Ament, Katherine; Karsjen, Steven; Leshem-Ackerman, Adah & King, Alexander
Object Type: Article
System: The UNT Digital Library
Visualization of Atomization Gas Flow and Melt Break-up Effects in Response to Nozzle Design (open access)

Visualization of Atomization Gas Flow and Melt Break-up Effects in Response to Nozzle Design

Both powder particle size control and efficient use of gas flow energy are highly prized goals for gas atomization of metal and alloy powder to minimize off-size powder inventory (or 'reverb') and excessive gas consumption. Recent progress in the design of close-coupled gas atomization nozzles and the water model simulation of melt feed tubes were coupled with previous results from several types of gas flow characterization methods, e.g., aspiration measurements and gas flow visualization, to make progress toward these goals. Size distribution analysis and high speed video recordings of gas atomization reaction synthesis (GARS) experiments on special ferritic stainless steel alloy powders with an Ar+O{sub 2} gas mixture were performed to investigate the operating mechanisms and possible advantages of several melt flow tube modifications with one specific gas atomization nozzle. In this study, close-coupled gas atomization under closed wake gas flow conditions was demonstrated to produce large yields of ultrafine (dia.<20 {mu}m) powders (up to 32%) with moderate standard deviations (1.62 to 1.99). The increased yield of fine powders is consistent with the dual atomization mechanisms of closed wake gas flow patterns in the near-field of the melt orifice. Enhanced size control by stabilized pre-filming of the melt with a …
Date: April 1, 2011
Creator: Anderson, Iver; Rieken, Joel; Meyer, John; Byrd, David & Heidloff, Andy
Object Type: Article
System: The UNT Digital Library
LIFE Delivery Plan (open access)

LIFE Delivery Plan

None
Date: April 18, 2011
Creator: Anklam, T M
Object Type: Report
System: The UNT Digital Library
LIFE: Recent Developments and Progress (open access)

LIFE: Recent Developments and Progress

Test results from the NIF show excellent progress toward achieving ignition. Experiments designed to verify coupling of the laser energy to the fusion target have shown that the efficiency meets that needed for ignition. Several tests with the cryogenic targets needed for ignition have been performed, and world-record neutron output produced. The National Ignition Campaign is on schedule to meet its 2012 ignition milestone, with the next phase in the campaign due to start later this month. It has been a busy and very productive year. The NIF is in full 24/7 operations and has progressed markedly in the path toward ignition. The long-standing goal of the National Ignition Campaign to demonstrate ignition by the end of FY 2012 is on track. The LIFE plant design has matured considerably, and a delivery plan established based on close interactions with vendors. National-level reviews of fusion are underway, and are due to present initial findings later this year. A value proposition has been drafted for review. The LIFE project is ready to move into the delivery phase.
Date: April 8, 2011
Creator: Anklam, T M
Object Type: Report
System: The UNT Digital Library
LIFE Cost of Electricity, Capital and Operating Costs (open access)

LIFE Cost of Electricity, Capital and Operating Costs

Successful commercialization of fusion energy requires economic viability as well as technical and scientific feasibility. To assess economic viability, we have conducted a pre-conceptual level evaluation of LIFE economics. Unit costs are estimated from a combination of bottom-up costs estimates, working with representative vendors, and scaled results from previous studies of fission and fusion plants. An integrated process model of a LIFE power plant was developed to integrate and optimize unit costs and calculate top level metrics such as cost of electricity and power plant capital cost. The scope of this activity was the entire power plant site. Separately, a development program to deliver the required specialized equipment has been assembled. Results show that LIFE power plant cost of electricity and plant capital cost compare favorably to estimates for new-build LWR's, coal and gas - particularly if indicative costs of carbon capture and sequestration are accounted for.
Date: April 14, 2011
Creator: Anklam, T.
Object Type: Report
System: The UNT Digital Library
Magnetic Alignment of Pulsed Solenoids Using the Pulsed Wire Method (open access)

Magnetic Alignment of Pulsed Solenoids Using the Pulsed Wire Method

A unique application of the pulsed-wire measurement method has been implemented for alignment of 2.5 T pulsed solenoid magnets. The magnetic axis measurement has been shown to have a resolution of better than 25 {micro}m. The accuracy of the technique allows for the identification of inherent field errors due to, for example, the winding layer transitions and the current leads. The alignment system is developed for the induction accelerator NDCX-II under construction at LBNL, an upgraded Neutralized Drift Compression experiment for research on warm dense matter and heavy ion fusion. Precise alignment is essential for NDCX-II, since the ion beam has a large energy spread associated with the rapid pulse compression such that misalignments lead to corkscrew deformation of the beam and reduced intensity at focus. The ability to align the magnetic axis of the pulsed solenoids to within 100 pm of the induction cell axis has been demonstrated.
Date: April 1, 2011
Creator: Arbelaez, D.; Madur, A.; Lipton, T. M.; Waldron, W. L. & Kwan, J. W.
Object Type: Article
System: The UNT Digital Library
Analytic 1D pn junction diode photocurrent solutions following ionizing radiation and including time-dependent changes in the carrier lifetime. (open access)

Analytic 1D pn junction diode photocurrent solutions following ionizing radiation and including time-dependent changes in the carrier lifetime.

Circuit simulation tools (e.g., SPICE) have become invaluable in the development and design of electronic circuits in radiation environments. These codes are often employed to study the effect of many thousands of devices under transient current conditions. Device-scale simulation tools (e.g., MEDICI) are commonly used in the design of individual semiconductor components, but require computing resources that make their incorporation into a circuit code impossible for large-scale circuits. Analytic solutions to the ambipolar diffusion equation, an approximation to the carrier transport equations, may be used to characterize the transient currents at nodes within a circuit simulator. We present new transient 1D excess carrier density and photocurrent density solutions to the ambipolar diffusion equation for low-level radiation pulses that take into account a finite device geometry, ohmic fields outside the depleted region, and an arbitrary change in the carrier lifetime due to neutron irradiation or other effects. The solutions are specifically evaluated for the case of an abrupt change in the carrier lifetime during or after, a step, square, or piecewise linear radiation pulse. Noting slow convergence of the raw Fourier series for certain parameter sets, we use closed-form formulas for some of the infinite sums to produce 'partial closed-form' solutions …
Date: April 1, 2011
Creator: Axness, Carl L.; Keiter, Eric Richard & Kerr, Bert (New Mexico Tech, Socorro, NM)
Object Type: Report
System: The UNT Digital Library
Study of the Variation of Transverse Voltage in the 4 Rod Crab Cavity for LHC (open access)

Study of the Variation of Transverse Voltage in the 4 Rod Crab Cavity for LHC

The planned high luminosity upgrade to LHC will utilise crab cavities to rotate the beam in order to increase the luminosity in the presence of a finite crossing angle. A compact design is required in order for the cavities to fit between opposing beam-lines. In this paper we discuss we discuss one option for the LHC crab cavity based on a 4 rod TEM deflecting cavity. Due to the large transverse size of the LHC beam the cavity is required to have a large aperture while maintaining a constant transverse voltage across the aperture. The cavity has been optimised to minimise the variation of the transverse voltage while keeping the peak surface electric and magnetic fields low for a given kick. This is achieved while fitting within the strict design space of the LHC. The variation of deflecting voltage across the aperture has been studied numerically and compared with numerical and analytical estimates of other deflecting cavity types. Performance measurements an aluminium prototype of this cavity are presented and compared to the simulated design.
Date: April 1, 2011
Creator: B. Hall, G. Burt, C. Lingwood, R. Rimmer, H. Wang
Object Type: Article
System: The UNT Digital Library
Scaling hypre's multigrid solvers to 100,000 cores (open access)

Scaling hypre's multigrid solvers to 100,000 cores

None
Date: April 6, 2011
Creator: Baker, A H; Falgout, R D; Kolev, T V & Yang, U M
Object Type: Article
System: The UNT Digital Library
Numerical Error Estimation for Nonlinear Hyperbolic PDEs via Nonlinear Error Transport (open access)

Numerical Error Estimation for Nonlinear Hyperbolic PDEs via Nonlinear Error Transport

None
Date: April 1, 2011
Creator: Banks, J W; Hittinger, J F; Connors, J M & Woodward, C S
Object Type: Article
System: The UNT Digital Library
Aquatic Natural Areas Analysis and Evaluation: Oak Ridge Reservation (open access)

Aquatic Natural Areas Analysis and Evaluation: Oak Ridge Reservation

This report presents an assessment of the natural area value of eight Aquatic Natural Areas (ANAs) and seven Aquatic Reference Areas (ARAs) on the Oak Ridge Reservation (ORR) in Anderson and Roane Counties in east Tennessee. It follows a previous study in 2009 that analyzed and evaluated terrestrial natural areas on the Reservation. The purpose of both studies was to evaluate and rank those specially designated areas on the Reservation that contain sensitive species, special habitats, and natural area value. Natural areas receive special protections through established statutes, regulations, and policies. The ORR contains 33,542 acres (13,574 ha) administered by the Department of Energy. The surface waters of the Reservation range from 1st-order to 5th-order streams, but the majority of the streams recognized as ANAs and ARAs are 1st- and 2nd-order streams. East Fork Poplar Creek is a 4th-order stream and the largest watershed that drains Reservation lands. All the waters of the Reservation eventually reach the Clinch River on the southern and western boundaries of the ORR. All available information was collected, synthesized, and evaluated. Field observations were made to support and supplement the available information. Geographic information system mapping techniques were used to develop several quantitative attributes about …
Date: April 1, 2011
Creator: Baranski, Michael J.
Object Type: Report
System: The UNT Digital Library
Finite Deformation of Magnetoelastic Film (open access)

Finite Deformation of Magnetoelastic Film

None
Date: April 29, 2011
Creator: Barham, M I
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Magnetoelasticity of highly deformable thin films: Theory and simulation (open access)

Magnetoelasticity of highly deformable thin films: Theory and simulation

None
Date: April 29, 2011
Creator: Barham, M I; Steigmann, D J & White, D
Object Type: Article
System: The UNT Digital Library
Corrigenda: Finite deformation of a pressurized magnetoelastic membrane in a stationary dipole field (open access)

Corrigenda: Finite deformation of a pressurized magnetoelastic membrane in a stationary dipole field

None
Date: April 29, 2011
Creator: Barham, M.; Steigmann, D. J.; McElfresh, M. & Rudd, R. E.
Object Type: Article
System: The UNT Digital Library
Guam Initial Technical Assessment Report (open access)

Guam Initial Technical Assessment Report

Under an interagency agreement, funded by the Department of Interior's (DOI) Office of Insular Affairs (OIA), the National Renewable Energy Laboratory (NREL) was tasked to deliver technical assistance to the island of Guam by conducting an island initial technical assessment that would lay out energy consumption and production data and establish a baseline. This assessment will be used to conduct future analysis and studies by NREL that will estimate energy efficiency and renewable energy potential for the island of Guam.
Date: April 1, 2011
Creator: Baring-Gould, I.; Conrad, M.; Haase, S.; Hotchkiss, E. & McNutt, P.
Object Type: Report
System: The UNT Digital Library
Simulations of NDCX-II Targets for Warm Dense Matter and Heavy Ion Fusion Physics (open access)

Simulations of NDCX-II Targets for Warm Dense Matter and Heavy Ion Fusion Physics

None
Date: April 28, 2011
Creator: Barnard, J. J.; Friedman, A.; Perkins, L. J.; Bieniosek, F. M.; Hay, M.; Henestroza, E. et al.
Object Type: Article
System: The UNT Digital Library
Drive Cycle Analysis, Measurement of Emissions and Fuel Consumption of a PHEV School Bus: Preprint (open access)

Drive Cycle Analysis, Measurement of Emissions and Fuel Consumption of a PHEV School Bus: Preprint

The National Renewable Energy Laboratory (NREL) collected and analyzed real-world school bus drive cycle data and selected similar standard drive cycles for testing on a chassis dynamometer. NREL tested a first-generation plug-in hybrid electric vehicle (PHEV) school bus equipped with a 6.4L engine and an Enova PHEV drive system comprising a 25-kW/80 kW (continuous/peak) motor and a 370-volt lithium ion battery pack. A Bluebird 7.2L conventional school bus was also tested. Both vehicles were tested over three different drive cycles to capture a range of driving activity. PHEV fuel savings in charge-depleting (CD) mode ranged from slightly more than 30% to a little over 50%. However, the larger fuel savings lasted over a shorter driving distance, as the fully charged PHEV school bus would initially operate in CD mode for some distance, then in a transitional mode, and finally in a charge-sustaining (CS) mode for continued driving. The test results indicate that a PHEV school bus can achieve significant fuel savings during CD operation relative to a conventional bus. In CS mode, the tested bus showed small fuel savings and somewhat higher nitrogen oxide (NOx) emissions than the baseline comparison bus.
Date: April 1, 2011
Creator: Barnitt, R. & Gonder, J.
Object Type: Article
System: The UNT Digital Library