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Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $454.75 reconciled for the period ending on July 14, 2001.
Date: July 14, 2001
Creator: unknown
System: The UNT Digital Library
Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $1,076.54 reconciled for the period ending on January 31, 2002.
Date: February 14, 2002
Creator: unknown
System: The UNT Digital Library
Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $1,247.07 reconciled for the period ending on June 28, 2002.
Date: July 14, 2002
Creator: unknown
System: The UNT Digital Library
Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $454.75 reconciled for the period ending on July 14, 2001.
Date: July 14, 2001
Creator: unknown
System: The UNT Digital Library
Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zone at Hanford (open access)

Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zone at Hanford

The purpose of this study was to examine the hypothesis that clastic dikes could form a preferential flow path through the vadose zone to the water table at the Hanford Site. Clastic dikes are subvertical structures that form within sedimentary sequences after deposition, and cut across the original sedimentary layers. They are common throughout the Hanford Site, often occurring in organized polygonal networks. In the initial phase of the project, we analyzed the large-scale geometry of the clastic dikes and developed an algorithm for simulating their spatial distribution. This result will be useful in providing maps of the potential distribution of clastic dikes in areas where they are not exposed at the surface (e.g., where covered by windblown sand or by construction of facilities like tank farms at the surface). In addition to the study of the large scale distribution of the dikes, a major focus of the project was on field, laboratory, and modeling studies of the hydrogeologic al properties of the clastic dikes and the effect that they have on transport of water through the vadose zone. These studies were performed at two field locations at the Hanford Site. We performed an extensive series of field and laboratory …
Date: March 14, 2003
Creator: Murray, Christopher J.; Ward, Anderson L. & Wilson, John L.
System: The UNT Digital Library
Dynamic Data-Driven Event Reconstruction for Atmospheric Releases (open access)

Dynamic Data-Driven Event Reconstruction for Atmospheric Releases

This is a collaborative LDRD Exploratory Research project involving four directorates--Energy & Environment, Engineering, NAI and Computation. The project seeks to answer the following critical questions regarding atmospheric releases--''How much material was released? When? Where? and What are the potential consequences?'' Inaccurate estimation of the source term can lead to gross errors, time delays during a crisis, and even fatalities. We are developing a capability that seamlessly integrates observational data streams with predictive models in order to provide the best possible estimates of unknown source term parameters, as well as optimal and timely situation analyses consistent with both models and data. Our approach utilizes Bayesian inference and stochastic sampling methods (Markov Chain and Sequential Monte Carlo) to reformulate the inverse problem into a solution based on efficient sampling of an ensemble of predictive simulations, guided by statistical comparisons with data. We are developing a flexible and adaptable data-driven event-reconstruction capability for atmospheric releases that provides (1) quantitative probabilistic estimates of the principal source-term parameters (e.g., the time-varying release rate and location); (2) predictions of increasing fidelity as an event progresses and additional data become available; and (3) analysis tools for sensor network design and uncertainty studies. Our computational framework incorporates …
Date: March 14, 2005
Creator: Mirin, A; Serban, R & Kosovic, B
System: The UNT Digital Library
Updated Volumetric Expansion Factors for K Basin Sludge During Storage (open access)

Updated Volumetric Expansion Factors for K Basin Sludge During Storage

Sludge has accumulated in the K East (KE) and K West (KW) Basins at the Hanford Site. This sludge contains metallic uranium and uranium oxides that will corrode, hydrate, and generate and consume gases during containerized storage. From these corrosion reactions, two sludge expansion mechanisms can be expected: 1) expansion of the volume of the sludge solids from the generation of corrosion oxidation products that occupy more space than the starting-state sludge; and 2) expansion of the bulk sludge volume from the retention of hydrogen gas bubbles. This report provides a review and updated projections of the volumetric expansion occurring due to corrosion and gas retention during the containerized storage of K Basin sludge. New design and safety basis volume expansion values are provided for the following sludge streams: KW Floor, KW North Loadout Pit, KW canister, and fuel piece sludge.
Date: March 14, 2003
Creator: Schmidt, Andrew J. (BATTELLE (PACIFIC NW LAB)) & Delegard, Calvin H. (BATTELLE (PACIFIC NW LAB))
System: The UNT Digital Library
Nuclear structure with accurate chiral perturbation theory nucleon-nucleon potential: Application to 6Li and 10B (open access)

Nuclear structure with accurate chiral perturbation theory nucleon-nucleon potential: Application to 6Li and 10B

The authors calculate properties of A = 6 system using the accurate charge-dependent nucleon-nucleon (NN) potential at fourth order of chiral perturbation theory. By application of the ab initio no-core shell model (NCSM) and a variational calculation in the harmonic oscillator basis with basis size up to 16 {h_bar}{Omega} they obtain the {sup 6}Li binding energy of 28.5(5) MeV and a converged excitation spectrum. Also, they calculate properties of {sup 10}B using the same NN potential in a basis space of up to 8 {h_bar}{Omega}. The results are consistent with results obtained by standard accurate NN potentials and demonstrate a deficiency of Hamiltonians consisting of only two-body terms. At this order of chiral perturbation theory three-body terms appear. It is expected that inclusion of such terms in the Hamiltonian will improve agreement with experiment.
Date: October 14, 2003
Creator: Navratil, P & Caurier, E
System: The UNT Digital Library
Evaluation of Nevada Test Site Ground Motion and Rock Property Data to Bound Ground Motions at the Yucca Mountain Repository (open access)

Evaluation of Nevada Test Site Ground Motion and Rock Property Data to Bound Ground Motions at the Yucca Mountain Repository

Yucca Mountain licensing will require estimation of ground motions from probabilistic seismic hazard analyses (PSHA) with annual probabilities of exceedance on the order of 10{sup -6} to 10{sup -7} per year or smaller, which correspond to much longer earthquake return periods than most previous PSHA studies. These long return periods for the Yucca Mountain PSHA result in estimates of ground motion that are extremely high ({approx} 10 g) and that are believed to be physically unrealizable. However, there is at present no generally accepted method to bound ground motions either by showing that the physical properties of materials cannot maintain such extreme motions, or the energy release by the source for such large motions is physically impossible. The purpose of this feasibility study is to examine recorded ground motion and rock property data from nuclear explosions to determine its usefulness for studying the ground motion from extreme earthquakes. The premise is that nuclear explosions are an extreme energy density source, and that the recorded ground motion will provide useful information about the limits of ground motion from extreme earthquakes. The data were categorized by the source and rock properties, and evaluated as to what extent non-linearity in the material has …
Date: February 14, 2005
Creator: Hutchings, L. J.; Foxall, W.; Rambo, J. & Wagoner, J. L.
System: The UNT Digital Library
Mechanical properties of D0 Run IIB silicon detector staves (open access)

Mechanical properties of D0 Run IIB silicon detector staves

A proposed stave design for the D0 Run IIb silicon tracker outer layers featuring central cooling channels and a composite shell mechanical structure is evaluated for self-deflection and deflection due to external loads. This paper contains an introduction to the stave structure, a section devoted to composite lamina and laminate properties and finally a section discussing the beam deflections expected for assembled staves using these laminates.
Date: June 14, 2001
Creator: Lanfranco, Giobatta & Fast, James
System: The UNT Digital Library
Fabrication of Efficient, Large Aperture Transmission Diffraction Gratings by Ion-Beam Etching (open access)

Fabrication of Efficient, Large Aperture Transmission Diffraction Gratings by Ion-Beam Etching

The utilization of high-power short pulse laser employing chirped-pulse amplification (CPA) for material processing and inertial confinement research is widely increasing. The performance of these high-power CPA laser system continues to be limited by the ability of the pulse compression gratings to hold up to the high-average-power or high-peak-power of the laser. Pulse compression gratings used in transmission and fabricated out of bulk fused silica have intrinsically the highest laser damage threshold when compared with metal or multilayer dielectric gratings that work in reflection. LLNL has developed processing capability to produce high efficiency fused silica transmission gratings at sizes useful to future Petawatt-class systems, and has demonstrated high efficiency at smaller aperture. This report shows that fused silica diffraction exhibiting >95% efficiency into the -1 diffraction order in transmission (90{sup o} deflection of the incident light, at an incidence angle of 45{sup o} to the grating face). The microstructure of this grating consisted of grooves ion-beam etched to a depth of 1.6 microns with a pitch of 0.75 microns, using a holographically produced photoresist mask that was subsequently stripped away in significance to the fabrication of the small scale high efficiency grating was the development of the processing technology and …
Date: September 14, 2000
Creator: Nguyen, H T; Bryan, S R; Britten, J A & Perry, M D
System: The UNT Digital Library
Investigating the Heating of a Potassium-Doped Aluminosilicate Ion Source Using a 1 Micron Laser (open access)

Investigating the Heating of a Potassium-Doped Aluminosilicate Ion Source Using a 1 Micron Laser

The heavy ion fusion (HIF) program is interested in developing a high brightness ion source for high energy density physics (HEDP) experiments. One possible approach to obtaining higher brightness may be to raise the surface temperature of the ion source just prior to extraction. The current ion source material being studied is a layer of potassium-doped aluminosilicate bonded to a tungsten substrate. It is speculated that if the surface temperature of the source is raised above 1200 C (from a steady-state temperature of 900 C) for time periods on the order of 100's of nanoseconds, current densities of greater than 100 mA/cm{sup 2} of ions may be achievable. Typical aluminosilicate sources produce ion current densities (either K+ or Na+ ions) of {approx}10 mA/cm{sup 2} (at 1100 C). A number of heating methods might be possible, including lasers, diode arrays, and flash lamps. Here we assume laser heating. In this preliminary study, we used the LLNL RadHeat code to model the time-temperature history of the surface when hit by laser pulses and illustrate how RadHeat can be used to optimize the surface temperature response. Also of interest is the temperature history of the interface temperature between the ceramic and the metal …
Date: December 14, 2004
Creator: Schmitt, R. C.; Meier, W. R.; Kwan, J. W.; Abbott, R. P. & Latkowski, J. F.
System: The UNT Digital Library
TEM verification of the <111>-type 4-arm multi-junction in [001]-Mo single crystals (open access)

TEM verification of the <111>-type 4-arm multi-junction in [001]-Mo single crystals

To investigate and verify the formation of <111>-type 4-arm multi-junction by the dislocation reaction of 1/2[111] [b1] + 1/2[{bar 1}1{bar 1}] [b2] + 1/2[{bar 1}{bar 1}1] [b3] = 1/2[{bar 1}11] [b4], which has recently been discovered through computer simulations conducted by Vasily Bulatov and his colleagues.
Date: March 14, 2005
Creator: Hsiung, L
System: The UNT Digital Library
Investigation into the Role of Initial Conditions on Rayleigh-Taylor Instabilities by Low Atwood Experiments and Simulations (open access)

Investigation into the Role of Initial Conditions on Rayleigh-Taylor Instabilities by Low Atwood Experiments and Simulations

The primary goal of the research being conducted this summer is to investigate the role of initial conditions in the development of a two fluid mix driven by Rayleigh-Taylor instability. The effects of initial conditions will be studied through the use of experimental facilities located at the Buoyancy-Driven Mixing Lab at Texas A&M University and through high resolution direct numerical simulations of the experiment by the MIRANDA code developed at Lawrence Livermore National Lab. The Experimental Objectives are: (1) Analyze the early time development of a two fluid Rayleigh-Taylor driven mix between two miscible fluids at low Atwood numbers. (2) Quantify the initial conditions of the unstably stratified fluids by means of statistical mixing parameters and spectral analysis of the centerline density fluctuations. (3) Capture PLIF images of initial development of the flow for use in simulation setup. (Wayne Kraft) (4) Determine exactly what component of the experimental mixing data (position downstream from the splitter plate) most accurately represents the initial conditions of the experiment. The Simulation Objectives are: (1) Perform two dimensional and three dimensional simulations of the experimental setup. Analyze the results of these simulations for comparison to the experimental results. (2) Various methods of implementing the initial …
Date: July 14, 2003
Creator: Mueschke, N; Andrews, M & Schilling, O
System: The UNT Digital Library
Evaluation of Fish Losses through Screen Gaps at Modified and Unmodified Intakes of Bonneville Dam Second Powerhouse in 2003 (open access)

Evaluation of Fish Losses through Screen Gaps at Modified and Unmodified Intakes of Bonneville Dam Second Powerhouse in 2003

This report was prepared by the Pacific Northwest National Lab., Richland, Washington, BAE Systems, Inc., a subcontractor to the U.S. Army Engineer Research and Development Center (ERDC), Vicksburg, Mississippi. This study examined the effect of gatewell modifications on the proportion of fish lost through the gap between the top of submerged traveling screens (STSs) and the ceilings of intakes in one un-modified and two modified turbine units at Bonneville Dam Second Powerhouse (B2). Combined modifications reduced the proportion of flow through the gap from 44% to 16% and increased the proportion moving up the gatewell from 56% to 84%. We used a Dual-Frequency Identification Sonar (DIDSON) acoustic camera to record proportions of juvenile salmonids moving up into the gatewell and through the gap. The acoustic camera was used to record images of fish passing up into the gatewell and through the gap for 8-h on three successive nights in every intake of units 13, 15, and 17 (i.e., 9 intakes x 3 nights = 27 nights each season). Only 28.6% of the objects detected in spring and 12.9% in summer were determined to be fish. Other objects included sticks and debris. Although the true magnitude of STS gap-loss is unknown, …
Date: June 14, 2004
Creator: Ploskey, Gene R.; Weiland, Mark A. & Schilt, Carl R.
System: The UNT Digital Library
ViSUS: Visualization Streams for Ultimate Scalability (open access)

ViSUS: Visualization Streams for Ultimate Scalability

In this project we developed a suite of progressive visualization algorithms and a data-streaming infrastructure that enable interactive exploration of scientific datasets of unprecedented size. The methodology aims to globally optimize the data flow in a pipeline of processing modules. Each module reads a multi-resolution representation of the input while producing a multi-resolution representation of the output. The use of multi-resolution representations provides the necessary flexibility to trade speed for accuracy in the visualization process. Maximum coherency and minimum delay in the data-flow is achieved by extensive use of progressive algorithms that continuously map local geometric updates of the input stream into immediate updates of the output stream. We implemented a prototype software infrastructure that demonstrated the flexibility and scalability of this approach by allowing large data visualization on single desktop computers, on PC clusters, and on heterogeneous computing resources distributed over a wide area network. When processing terabytes of scientific data, we have achieved an effective increase in visualization performance of several orders of magnitude in two major settings: (i) interactive visualization on desktop workstations of large datasets that cannot be stored locally; (ii) real-time monitoring of a large scientific simulation with negligible impact on the computing resources available. …
Date: February 14, 2005
Creator: Pascucci, V
System: The UNT Digital Library
FY2001 Annual Report for EMSP Project #70108: Effects of Fluid Distribution on Measured Geophysical Properties for Partially Saturated, Shallow Subsurface Conditions (open access)

FY2001 Annual Report for EMSP Project #70108: Effects of Fluid Distribution on Measured Geophysical Properties for Partially Saturated, Shallow Subsurface Conditions

Our goal is to improve geophysical imaging of the vadose zone. We will achieve this goal by providing new methods to improve interpretation of field data. The purpose of this EMSP project is to develop relationships between laboratory measured geophysical properties and porosity, saturation, and fluid distribution, for partially saturated soils. Algorithms for relationships between soil composition, saturation, and geophysical measurements will provide new methods to interpret geophysical field data collected in the vadose zone at sites such as Hanford, WA.
Date: June 14, 2001
Creator: Berge, P. A.; Bonner, B. P.; Roberts, J. J.; Wildenschild, D.; Aracne-Ruddle, C. M.; Berryman, J. G. et al.
System: The UNT Digital Library
Adaptive 4-8 Texture Hierarchies (open access)

Adaptive 4-8 Texture Hierarchies

None
Date: April 14, 2004
Creator: Hwa, L M; Duchaineau, M A & Joy, K I
System: The UNT Digital Library
General Constraints on Cross Sections Deduced from Surrogate Reactions (open access)

General Constraints on Cross Sections Deduced from Surrogate Reactions

Cross sections that cannot be measured in the laboratory, e.g. because the target lifetime is too short, can be inferred indirectly from a different reaction forming the same compound system, but with a more accessible beam/target combination (the ''surrogate-reaction'' technique). The reactions share the same compound system and a common decay mechanism, but they involve different formation processes. Therefore, an implicit constraint is imposed on the inferred cross section deduced from the measured surrogate-reaction data, through the common decay mechanism. In this paper, the mathematical consequences of this implicit constraint are investigated. General formulas are derived from upper and lower bounds on the inferred cross section, estimated from surrogate data in a procedure which does not require any modeling of the common decay process. As an example, the formulas developed here are applied to the case of the {sup 235}U(n,f) cross section, deduced from {sup 234}U(t,pf) surrogate data. The calculated bounds are not very tight in this particular case. However, by introducing a few qualitative assumptions about the physics of the fission process, meaningful bounds on the deduced cross section are obtained. Upper and lower limits for the cross-section ratio of the (n,f) reaction on the {sup 235}U isomer at …
Date: August 14, 2003
Creator: Younes, W.
System: The UNT Digital Library
Groundwater Monitoring Plan for the 216-B-63 Trench on the Hanford Site (open access)

Groundwater Monitoring Plan for the 216-B-63 Trench on the Hanford Site

This document presents a groundwater monitoring plan for the 216-B-63 trench in the 200 East Area of the Hanford Site. The monitoring will be conducted in accordance with regulatory requirements specified in the Resource Conservation and Recovery Act (RCRA) of 1976. The objective of the monitoring is to determine whether any hazardous constituents are detectable in the groundwater beneath the trench. This monitoring plan will serve as the basis for demonstrating monitoring compliance at the B-63 trench under the RCRA.
Date: November 14, 2002
Creator: Sweeney, Mark D.
System: The UNT Digital Library
Modeling the Production of Beta-Delayed Gamma Rays for the Detection of Special Nuclear Materials (open access)

Modeling the Production of Beta-Delayed Gamma Rays for the Detection of Special Nuclear Materials

The objective of this LDRD project was to develop one or more models for the production of {beta}-delayed {gamma} rays following neutron-induced fission of a special nuclear material (SNM) and to define a standardized formatting scheme which will allow them to be incorporated into some of the modern, general-purpose Monte Carlo transport codes currently being used to simulate inspection techniques proposed for detecting fissionable material hidden in sea-going cargo containers. In this report, we will describe a Monte Carlo model for {beta}-delayed {gamma}-ray emission following the fission of SNM that can accommodate arbitrary time-dependent fission rates and photon collection histories. The model involves direct sampling of the independent fission yield distributions of the system, the branching ratios for decay of individual fission products and spectral distributions representing photon emission from each fission product and for each decay mode. While computationally intensive, it will be shown that this model can provide reasonably detailed estimates of the spectra that would be recorded by an arbitrary spectrometer and may prove quite useful in assessing the quality of evaluated data libraries and identifying gaps in the libraries. The accuracy of the model will be illustrated by comparing calculated and experimental spectra from the decay …
Date: February 14, 2005
Creator: Hall, J. M.; Pruet, J. A.; Brown, D. A.; Descalle, M.; Hedstrom, G. W. & Prussin, S. G.
System: The UNT Digital Library
Attempts to Produce D2-Gas-Filled Be Shells (open access)

Attempts to Produce D2-Gas-Filled Be Shells

We have attempted to fabricate some 0.5 mm diameter D{sub 2}-gas-filled Be shells by coating gas-filled PVA-coated GDP mandrels with Cu-doped Be. We find that during the coating all (or most) of the gas leaks out. This is likely due to either small cracks or holes in the coating that are formed at the earliest points and are maintained during the thickness build-up of the coating, and/or to some level of intrinsic porosity in the coating. This memo documents our efforts.
Date: January 14, 2005
Creator: Cook, Bob; McElfresh, Mike; Alford, Craig; Fought, Eric & Letts, Steve
System: The UNT Digital Library
Critical Density Interaction Studies (open access)

Critical Density Interaction Studies

Experiments have been performed to study the propagation of intense laser pulses to high plasma densities. The issue of self-focusing and filamentation of the laser pulse as well as developing predictive capability of absorption processes and x-ray conversion efficiencies is important for numerous programs at the Laboratory, particularly Laser Program (Fast Ignitor and direct-drive ICF) and D&NT (radiography, high energy backlighters and laser cutting). Processes such as resonance absorption, profile modification, linear mode conversion, filamentation and stimulated Brillouin scattering can occur near the critical density and can have important effects on the coupling of laser light to solid targets. A combination of experiments have been used to study the propagation of laser light to high plasma densities and the interaction physics of intense laser pulses with solid targets. Nonparaxial fluid codes to study nonstationary behavior of filamentation and stimulated Brillouin scattering at high densities have also been developed as part of this project.
Date: February 14, 2001
Creator: Young, P.; Baldis, H. A.; Cheung, P.; Rozmus, W.; Kruer, W.; Wilks, S. et al.
System: The UNT Digital Library
Diode-Laser Phase Conjugation 03-FS-030 Final Report (open access)

Diode-Laser Phase Conjugation 03-FS-030 Final Report

Arrays of lasers are often considered when a need exists to increase laser optical output power, for a variety of purposes. Similarly, individual semiconductor laser-diodes, generating 0.01-1.0 W each, are commonly placed in arrays in order to increase total optical power onto targeted objects. Examples of such usage are diode-laser pump arrays for solid-slab heat-capacity lasers, laser arrays for heat-treating materials, and arrays for efficient solid state laser systems. The commercial and defense communities also use such arrays for many applications from laser range-finders, laser designators, to laser machining systems, etc. However, the arraying process does not automatically increase ''focusable'' light on target (i.e., intensity/steradian). For those applications requiring the highest focusability, it is necessary that the collective output beam from arrays of individual lasers be phase-coherent. Under this condition, the individual laser-element optical outputs are ''fused together'' into a larger area, phase coherent (i.e., all wavefronts are ''in step''), high-power combined beam. The process of joining multiple laser beams together to produce a single coherent wave, is in general very difficult and seldom accomplished. Thus joining together many hundreds to thousands of beams from individual laser-diodes, in large arrays, is still an unsolved problem. There are 2 major reasons …
Date: February 14, 2005
Creator: Page, R H; Beach, R J; Payne, S A & Holzrichter, J F
System: The UNT Digital Library