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[Deposit Summary and a Letter to Michael Milliken]

Description: Deposit summary of $45.00 made on May 9, 2001, and a letter to Michael Milliken from Daniel C. Graney, membership chair of the San Antonio Club regarding membership dues.
Date: May 9, 2001
Partner: UNT Libraries Special Collections
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Reconciliation Report

Description: Reconciliation report with an ending account balance of $425.00 reconciled for the period ending on May 9, 2001.
Date: May 9, 2001
Partner: UNT Libraries Special Collections
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Three-Dimensional Analysis of Voids in AM60B Magnesium Tensile Bars Using Computed Tomography Imagery

Description: In an effort to increase automobile fuel efficiency as well as decrease the output of harmful greenhouse gases, the automotive industry has recently shown increased interest in cast light metals such as magnesium alloys in an effort to increase weight savings. Currently several magnesium alloys such as AZ91 and AM60B are being used in structural applications for automobiles. However, these magnesium alloys are not as well characterized as other commonly used structural metals such as aluminum. This dissertation presents a methodology to nondestructively quantify damage accumulation due to void behavior in three dimensions in die-cast magnesium AM60B tensile bars as a function of mechanical load. Computed tomography data was acquired after tensile bars were loaded up to and including failure, and analyzed to characterize void behavior as it relates to damage accumulation. Signal and image processing techniques were used along with a cluster labeling routine to nondestructively quantify damage parameters in three dimensions. Void analyses were performed including void volume distribution characterization, nearest neighbor distance calculations, shape parameters, and volumetric renderings of voids in the alloy. The processed CT data was used to generate input files for use in finite element simulations, both two- and three-dimensional. The void analyses revealed that the overwhelming source of failure in each tensile bar was a ring of porosity within each bar, possibly due to a solidification front inherent to the casting process. The measured damage parameters related to void nucleation, growth, and coalescence were shown to contribute significantly to total damage accumulation. Void volume distributions were characterized using a Weibull function, and the spatial distributions of voids were shown to be clustered. Two-dimensional finite element analyses of the tensile bars were used to fine-tune material damage models and a three-dimensional mesh of an extracted portion of one tensile bar including voids was generated …
Date: May 1, 2001
Creator: Waters, A M
Partner: UNT Libraries Government Documents Department
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Comparison of Machining with Long-Pulse Green and Ultrashort Pulse Lasers

Description: (1) LLNL measured the material removal rate from stainless steel, silicon carbide, rhenium, N5, hastalloy X, and titanium as a function of pulse fluence at a wavelength of 810 nm for pulse durations of 150 fs, 1.5 ps, 20 ps, and 500 ps. The spot size of the beam used was 150 microns in diameter and the nominal material thickness was 1-2 mm. These experiments were performed on the existing 1 kHz laser system. Holes of different penetration depths were obtained to ascertain change in removal rate as a function of depth. Measurements included electron microscopy of selected samples. (2) The experiments in I were repeated for all materials but select pulse durations with the sample in a vacuum of base pressure 10 mTorr to determine if hole quality and ablation rate is improved. (3) LLNL measured material removal rate from stainless steel, silicon carbide, rhenium, N5, hastalloy X, and titanium as a function of pulse fluence at a wavelength of 532 nm for pulse duration at 200 ns. The spot size of the beam used was 200 microns in diameter and the material thickness was the same as in task I. Holes of different penetration depths were obtained to ascertain changes in removal rate as a function of depth.
Date: May 18, 2001
Creator: Wynne, A E & Stuart, B C
Partner: UNT Libraries Government Documents Department
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Why Model-Based Engineering and Manufacturing Makes Sense for the Plants and Laboratories of the Nuclear Weapon Complex

Description: The purpose of this White Paper is to outline the benefits we expect to receive from Model-Based Engineering and Manufacturing (MBE/M) for the design, analysis, fabrication, and assembly of nuclear weapons for upcoming Life Extension Programs (LEPs). Industry experiences with model-based approaches and the NNSA/DP investments and experiences, discussed in this paper, indicate that model-based methods can achieve reliable refurbished weapons for the stockpile with less cost and time. In this the paper, we list both general and specific benefits of MBE/M for the upcoming LEPs and the metrics for determining the success of model-based approaches. We also present some outstanding issues and challenges to deploying and achieving long-term benefit from the MBE/M. In conclusion, we argue that successful completion of the upcoming LEPs--with very aggressive schedule and funding restrictions--will depend on electronic model-based methods. We ask for a strong commitment from LEP managers throughout the Nuclear Weapons Complex to support deployment and use of MBE/M systems to meet their program needs.
Date: May 15, 2001
Creator: Franklin, K. W.; Howell, L. N., Jr.; Lewis, D. G.; Neugebauer, C. A.; O'Brien, D. W. & Schilling, S. A.
Partner: UNT Libraries Government Documents Department
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25 Can Verification Report for the LLNL Plutonium Packaging System (PuPS)

Description: This document reports the results of the 25 Can Verification Run. The 25 Can Verification Run was performed as outlined in Section 1.d of SRS Acceptance Criteria (Reference 1). The run was performed over the period of February 16 to the 28, 2001. Each of these cans was welded with a dummy Inner Can containing about 5 kg of surrogate material. The cans were then analyzed using radiography and metallography of samples taken at four locations of the weld. The radiographs were examined for porosity. The micrographs of the metallurgical samples were examined for porosity, cracks, and lack of fusion. The results were reviewed by Derrill Rikard (a level 3 inspector at LLNL) and by Ken Durland (a level 3 inspector from WSRC). These reviews did not find anything of concern. Therefore we are submitting these results to SRS for concurrence.
Date: May 7, 2001
Creator: Riley, D C & Dodson, K E
Partner: UNT Libraries Government Documents Department
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Workshop on the Increased Use of Ethanol and Alkylates in Automotive Fuels in California

Description: The goals of the Workshop are to: (1) Review the existing state of knowledge on (a) physicochemical properties, multi-media transport and fate, exposure mechanisms and (b) release scenarios associated with the production, distribution, and use of ethanol and alkylates in gasoline; (2) Identify key regulatory, environmental, and resource management issues and knowledge gaps associated with anticipated changes in gasoline formulation in California; and (3) Develop a roadmap for addressing issues/knowledge gaps.
Date: May 4, 2001
Creator: Rice, D W
Partner: UNT Libraries Government Documents Department
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2000 Engineering Annual Summary

Description: No Description Available.
Date: May 24, 2001
Creator: Gerich, C
Partner: UNT Libraries Government Documents Department
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Simulating Marvel with the Stun Code

Description: MARVEL, a nuclear-driven shock-tube experiment, consisted of a 2.2 kiloton nuclear explosive detonated 176 meters underground at one end of a 122-meter long, 1-meter diameter horizontal tunnel. Vaporization of material in the immediate vicinity of the explosive provided the source of high-energy driver gas. The driven gas was the ambient atmospheric air in the tunnel. The event was staged as an experimental and calculational study of the time dependent .ow of energy in the tunnel and surrounding alluvium. In this report we describe the derivation and implementation of a ''1-3/4D'' hydrocode to simulate the experiment. Calculations were performed to study the influence of energy transport to, and mass ablation from, the walls of the tunnel on the shock velocity.
Date: May 23, 2001
Creator: Glenn, L A
Partner: UNT Libraries Government Documents Department
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March 2001 Working Group Meeting on Heavy Vehicle Aerodynamic Drag: Presentations and Summary of Comments and Conclusions

Description: A Working Group Meeting on Heavy Vehicle Aerodynamic Drag was held at Lawrence Livermore National Laboratory on March 28 and 29, 2001. The purpose of the meeting was to present and discuss technical details on the experimental and computational work in progress and future project plans. Due to the large participation from industry and other research organizations, a large portion of the meeting (all of the first day and part of the second day) was devoted to the presentation and discussion of industry's perspective and work being done by other organizations on the demonstration of commercial software and the demonstration of a drag reduction device. This report contains the technical presentations (viewgraphs) delivered at the Meeting, briefly summarizes the comments and conclusions, and outlines the future action items.
Date: May 14, 2001
Creator: Greenman, R.; Dunn, T.; Owens, J.; Laskowski, G.; Flowers, D.; Browand, F. et al.
Partner: UNT Libraries Government Documents Department
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A Note on Differencing the Viscous Dissipation Terms for a Newtonian Fluid

Description: We compare two finite difference approximations for the viscous dissipation terms in the energy equation. We focus on the strain produced by the every-other-zone (e.g., hour-glass and herringbone) modes in the velocity field. Care must be exercised to produce a viscous dissipation rate consistent with the viscous forces. The examples given are for a rectangular staggered grid, but similar considerations apply to other types of grids. Also, these considerations apply to certain algebraic eddy viscosity models and to the shear creation terms in turbulence transport models.
Date: May 30, 2001
Creator: Cloutman, L
Partner: UNT Libraries Government Documents Department
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Methods for Addressing Uncertainty and Variability to Characterize Potential Health Risk from Trichloroethylene-Contaminated Ground Water at Beale Air Force Base in California:Integration of Uncertainty and Variability in Pharmacokinetics and Dose-Response

Description: Traditional estimates of health risk are typically inflated, particularly if cancer is the dominant endpoint and there is fundamental uncertainty as to mechanism(s) of action. Risk is more realistically characterized if it accounts for joint uncertainty and interindividual variability within a systematic probabilistic framework to integrate the joint effects on risk of distributed parameters of all (linear as well as nonlinear) risk-extrapolation models involved. Such a framework was used to characterize risks to potential future residents posed by trichloroethylene (TCE) in ground water at an inactive landfill site on Beale Air Force Base in California. Variability and uncertainty were addressed in exposure-route-specific estimates of applied dose, in pharmacokinetically based estimates of route-specific metabolized fractions of absorbed TCE, and in corresponding biologically effective doses estimated under a genotoxic/linear (MA{sub G}) vs. a cytotoxic/nonlinear (MA{sub c}) mechanistic assumption for TCE-induced cancer. Increased risk conditional on effective dose was estimated under MA{sub G} based on seven rodent-bioassay data sets, and under MA{sub c} based on mouse hepatotoxicity data. Mean and upper-bound estimates of combined risk calculated by the unified approach were <10{sup -6} and 10{sup -4}, respectively, while corresponding estimates based on traditional deterministic methods were >10{sup -5} and 10{sup -4}, respectively. It was estimated that no TCE-related harm is likely to occur due to any plausible residential exposure scenario involving the site. The systematic probabilistic framework illustrated is particularly suited to characterizing risks that involve uncertain and/or diverse mechanisms of action.
Date: May 24, 2001
Creator: Bogen, K T
Partner: UNT Libraries Government Documents Department
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Synthesis and Properties of a New Explosive, 4-Amino-3,5-Dinitro-lH-Pyrazole (LLM-116)

Description: A novel synthesis of the title compound was achieved by direct amination using Vicarious Nucleophilic Substitution (VNS) methodology. Reaction of 1,1,1-trimethylhydrazinium iodide with 3,5-dinitropyrazole in DMSO produces 4-amino-3,s-dinitro-1H-pyrazole as a 1:1 crystal solvate with DMSO. Recrystallization from water yields the monohydrated crystal. Recrystallization of the monohydrate from butyl acetate yields the compound in pure form. Crystallographic data and results of small-scale safety tests are reported. These data indicate that LLM-116 is a promising candidate as an insensitive high explosive.
Date: May 22, 2001
Creator: Schmidt, R. D.; Lee, G. S.; Pagoria, P. F.; Mitchell, A. R. & Gilardi, R.
Partner: UNT Libraries Government Documents Department
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A Report of the Joint Development of a Prototype Communications Link to Share Nuclear Accident Dispersion and Dose Assessment Modeling Products Between JAERI/WSPEEDI and LLNL/NARAC

Description: In June of 1997, under an umbrella Memorandum of Understanding between the Japan Atomic Energy Research Institute (JAERI) and the U.S. Department of Energy (US/DOE) concerning matters of nuclear research and development, a Specific Memorandum of Agreement (SMA) entitled ''A Collaborative Programme of Development of a Prototype Communication Link to Share Atmospheric Dispersion and Dose Assessment Modelling Products'' was signed. This SMA formalized an informal collaborative exchange between the DOE's Lawrence Livermore National Laboratory (LLNL) Atmospheric Release Advisory Capability (ARAC) center and the Japan Atomic Energy Research Institute (JAERI) Worldwide System for Prediction of Environmental Emergency Dose Information (WSPEEDI). The intended objective of this agreement was to explore various modes of information exchange, beyond facsimile transmission, which could provide for the quick exchange of information between two major nuclear emergency dose assessment and prediction national centers to provide consistency checks and data exchange before public release of their calculations. The extreme sensitivity of the general public to any nuclear accident information has been a strong motivation to seek peer preview prior to public release. Other intended objectives of this work are the development of an affordable/accessible system for distribution of prediction results to other countries having no prediction capabilities and utilization of the link for collaboration studies. To fulfill the objectives of this project JAERI and LLNL scientists determined to assess the evolving Internet and rapidly emerging communications application software. Our timing was a little early in 1997-1998 but nonetheless a few candidate software packages were found, evaluated and a selection was made for initial test and evaluation. Subsequently several new candidate software packages have arrived, albeit with limitations. This report outlines the ARAC and JAERI emergency response assessment systems, describes the prototype communications protocol system established and the tools evaluated in that process. Three real-time applications of the information …
Date: May 1, 2001
Creator: Sullivan, T J; Belles, R D; Ellis, J S; Chino, M & Nagai, H
Partner: UNT Libraries Government Documents Department
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AMRH and High Energy Reinicke Problem

Description: The authors describe AMRH results on a version of the Reinicke problem specified by the V and V group of LLNL's A-Div. The simulation models a point explosion with heat conduction. The problem specification requires that the heat conduction be replaced with diffusive radiation transport. The matter and radiation energy densities are tightly coupled.
Date: May 14, 2001
Creator: Shestakov, A I & Greenough, J A
Partner: UNT Libraries Government Documents Department
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An Assessment of the Current Day Impact of Various Materials Associated with the U.S. Nuclear Test Program in the Marshall Island

Description: Different stable elements, and some natural and man-made radionuclides, were used as tracers or associated in other ways with nuclear devices that were detonated at Bikini and Enewetak Atolls as part of the U.S. nuclear testing program from 1946 through 1958. The question has been raised whether any of these materials dispersed by the explosions could be of sufficient concentration in either the marine environment or on the coral islands to be of a health concern to people living, or planning to live, on the atolls. This report addresses that concern. An inventory of the materials involved during the test period was prepared and provided to us by the Office of Defense Programs (DP) of the United States Department of Energy (DOE). The materials that the DOE and the Republic of the Marshall Islands (RMI) ask to be evaluated are--sulfur, arsenic, yttrium, tantalum, gold, rhodium, indium, tungsten, thallium, thorium-230,232 ({sup 230,232}Th), uranium-233,238 ({sup 233,238}U), polonium-210 ({sup 210}Po), curium-232 ({sup 232}Cu), and americium-241 ({sup 241}Am). The stable elements were used primarily as tracers for determining neutron energy and flux, and for other diagnostic purposes in the larger yield, multistage devices. It is reasonable to assume that these materials would be distributed in a similar manner as the fission products subsequent to detonation. A large inventory of fission product and uranium data was available for assessment. Detailed calculations show only a very small fraction of the fission products produced during the entire test series remain at the test site atolls. Consequently, based on the information provided, we conclude that the concentration of these materials in the atoll environment pose no adverse health effects to humans.
Date: May 1, 2001
Creator: Robison, W L; Noshkin, V E; Hamilton, T F; Conrado, C L & Bogen, K T
Partner: UNT Libraries Government Documents Department
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Modeling the use of Self-Focused Beams to Overcome the Effects of Target Emissions in Advanced Hydrodynamic Radiography Machines

Description: In the machines being developed for advanced hydrodynamic radiography, an electron beam of several kA current and 20 Mev particle energy is focused to less than a millimeter diameter onto a high atomic number target to produce bremstrahlung X-rays. Several pulses occur during a period of about 2 {micro}s. A plasma plume is predicted to move upstream from the target . If the final focus onto the target is in vacuum, then the plasma from an early pulse may neutralize the self-electric field of a later pulse causing over-focusing (1). Also positive ions may be accelerated upstream by the self-electric field of a beam focused onto a conducting target in vacuum (1,2). The ions neutralize part of the self-electric field and so cause a time varying change of focusing.
Date: May 1, 2001
Creator: Lauer, E
Partner: UNT Libraries Government Documents Department
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Hydrogen Induced Cracking in Titanium Drip Shield of High-Level Waste Repository

Description: Both qualitative and quantitative assessments have been conducted to evaluate the effects of hydrogen induced cracking on the drip shield. The basic premise of the assessments is that failure will occur once the hydrogen content exceeds a certain limit or critical value, H{sub c}. Potential mechanisms for hydrogen absorption in the drip shield have been identified to be general passive corrosion and galvanic couple with steel components. Both qualitative and quantitative evaluations indicated that hydrogen concentration in the drip shield will be below the critical value by a considerable margin. The choice of the mathematical models and associated parameters appears to be reasonable. Continued effort in data collection and development should provide validation and improved level of confidence of the proposed models.
Date: May 30, 2001
Creator: Lu, S C
Partner: UNT Libraries Government Documents Department
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Addendum to the 200 West Area Dust Mitigation Strategies: Treatment of the Dust Source Area

Description: This document describes the source area for the blowing dust encountered in the southwest portion of the 200 West Area. Strategies for short-term stabilization of the entire source area, short-term stabilization of a portion of the source area based on levels of respirable dust, and long-term stabilization of the entire source area are provided. An separate evaluation of aerosolized water as a means of reducing airborne dust is also provided.
Date: May 14, 2001
Creator: Becker, James M. & Sackschewsky, Michael R.
Partner: UNT Libraries Government Documents Department
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Evaluation of the Hydrologic Source Term from Underground Nuclear Tests on Pahute Mesa at the Nevada Test Site: The CHESHIRE Test

Description: The objectives of this report are to develop, summarize, and interpret a series of detailed unclassified simulations that forecast the nature and extent of radionuclide release and near-field migration in groundwater away from the CHESHIRE underground nuclear test at Pahute Mesa at the NTS over 1000 yrs. Collectively, these results are called the CHESHIRE Hydrologic Source Term (HST). The CHESHIRE underground nuclear test was one of 76 underground nuclear tests that were fired below or within 100 m of the water table between 1965 and 1992 in Areas 19 and 20 of the NTS. These areas now comprise the Pahute Mesa Corrective Action Unit (CAU) for which a separate subregional scale flow and transport model is being developed by the UGTA Project to forecast the larger-scale migration of radionuclides from underground tests on Pahute Mesa. The current simulations are being developed, on one hand, to more fully understand the complex coupled processes involved in radionuclide migration, with a specific focus on the CHESHIRE test. While remaining unclassified, they are as site specific as possible and involve a level of modeling detail that is commensurate with the most fundamental processes, conservative assumptions, and representative data sets available. However, the simulation results are also being developed so that they may be simplified and interpreted for use as a source term boundary condition at the CHESHIRE location in the Pahute Mesa CAU model. In addition, the processes of simplification and interpretation will provide generalized insight as to how the source term behavior at other tests may be considered or otherwise represented in the Pahute Mesa CAU model.
Date: May 1, 2001
Creator: Pawloski, G. A.; Tompson, A. F. B.; Carle, S. F.; Bourcier, W. L.; Bruton, C. J.; Daniels, J. I. et al.
Partner: UNT Libraries Government Documents Department
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Identification of Process Hazards and Accident Scenarios for Site 300 B-Division Firing Areas, Lawrence Livermore National Laboratory

Description: This report describes a hazard and accident analysis conducted for Site 300 operations to support update of the ''Site 300 B-Division Firing Areas Safety Analysis Report'' (SAR) [LLNL 1997]. A significant change since the previous SAR is the construction and the new Contained Firing Facility (CFF). Therefore, this hazard and accident analysis focused on the hazards associated with bunker operations to ensure that the hazards at CFF are properly characterized in the updated SAR. Hazard tables were created to cover both the CFF and the existing bunkers with ''open air'' firing tables.
Date: May 4, 2001
Creator: Lambert, H & Johnson, G
Partner: UNT Libraries Government Documents Department
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Vadose Zone Transport Field Study: FY 2002 Test Plan

Description: The primary objective of the Vadose Zone Transport Field Study is to obtain hydrologic, geophysical, and geochemical data from controlled field studies to reduce the uncertainty in vadose-zone conceptual models and to facilitate the calibration of numerical models for water flow and contaminant transport through Hanford's heterogeneous vadose zone. A secondary objective is to evaluate advanced, cost-effective characterization methods with the potential to assess changing conditions in the vadose zone, particularly as surrogates of currently undetectable high-risk contaminants. The study is designed to assure the measurement of flow-and-transport properties in the same soil volume, a pre-requisite for developing techniques for extrapolating parameters derived from investigations at clean representative sites to contaminated sites with minimal characterization.
Date: May 1, 2001
Creator: Ward, Anderson L. & Gee, Glendon W.
Partner: UNT Libraries Government Documents Department
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Laboratory Directed Research and Development FY 2000 Annual Report

Description: This Annual Report provides an overview of the FY2000 Laboratory Directed Research and Development (LDRD) Program at Lawrence Livermore National Laboratory (LLNL) and presents a summary of the results achieved by each project during the year.
Date: May 24, 2001
Creator: Al-Ayat, R
Partner: UNT Libraries Government Documents Department
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The Cleaning of Aluminum Frame Assembly Units

Description: The Brulin immersion and the precision cleaning experiments have shown that neither the Brulin solution nor the precision cleaning in AstroPak causes the smut formation on aluminum surfaces. The acid-bath cleaning in GTC is the primary source of the smut formation. The current GTC acid formulation etches the aluminum matrix quite aggressively, but does not appear to appreciably attack the Si particles. Therefore, this acid-bath cleaning will leave the cast-aluminum part surfaces with many protruded Si particles, which could potentially cause smut problems in the cleaning process down-stream. To ensure the removal of all loose Si particles from the cast-aluminum parts, it is necessary to physically hand-wipe and vigorously wash the acid-bath cleaned surfaces. Furthermore, the casting porosity in alloy A356 could be another source in causing high swipe readings in the FAU parts.
Date: May 16, 2001
Creator: Shen, T H
Partner: UNT Libraries Government Documents Department
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