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Project Hanford management contract quality improvement project management plan (open access)

Project Hanford management contract quality improvement project management plan

On July 13, 1998, the U.S. Department of Energy, Richland Operations Office (DOE-RL) Manager transmitted a letter to Fluor Daniel Hanford, Inc. (FDH) describing several DOE-RL identified failed opportunities for FDH to improve the Quality Assurance (QA) Program and its implementation. In addition, DOE-RL identified specific Quality Program performance deficiencies. FDH was requested to establish a periodic reporting mechanism for the corrective action program. In a July 17, 1998 response to DOE-RL, FDH agreed with the DOE concerns and committed to perform a comprehensive review of the Project Hanford Management Contract (PHMC) QA Program during July and August, 1998. As a result, the Project Hanford Management Contract Quality Improvement Plan (QIP) (FDH-3508) was issued on October 21, 1998. The plan identified corrective actions based upon the results of an in-depth Quality Program Assessment. Immediately following the scheduled October 22, 1998, DOE Office of Enforcement and Investigation (EH-10) Enforcement Conference, FDH initiated efforts to effectively implement the QIP corrective actions. A Quality Improvement Project (QI Project) leadership team was assembled to prepare a Project Management Plan for this project. The management plan was specifically designed to engage a core team and the support of representatives from FDH and the major subcontractors …
Date: March 25, 1999
Creator: ADAMS, D.E.
Object Type: Report
System: The UNT Digital Library
Growth and Fabrication of GaN/AlGaN Heterojunction Bipolar Transistor (open access)

Growth and Fabrication of GaN/AlGaN Heterojunction Bipolar Transistor

A GaN/AlGaN heterojunction bipolar transistor structure with Mg doping in the base and Si Doping in the emitter and collector regions was grown by Metal Organic Chemical Vapor Deposition in c-axis Al(2)O(3). Secondary Ion Mass Spectrometry measurements showed no increase in the O concentration (2-3x10(18) cm(-3)) in the AlGaN emitter and fairly low levels of C (~4-5x10(17) cm (-3)) throughout the structure. Due to the non-ohmic behavior of the base contact at room temperature, the current gain of large area (~90 um diameter) devices was <3. Increasing the device operating temperature led to higher ionization fractions of the mg acceptors in the base, and current gains of ~10 were obtained at 300 degree C.
Date: March 16, 1999
Creator: Abernathy, C. R.; Baca, A. G.; Cao, X. A.; Cho, H.; Dang, G. T.; Donovan, S. M. et al.
Object Type: Article
System: The UNT Digital Library
Changes in Gas Bubble Disease Signs for Migrating Juvenile Salmonids Experimentally Exposed to Supersaturated Gasses, 1996-1997 Progress Report. (open access)

Changes in Gas Bubble Disease Signs for Migrating Juvenile Salmonids Experimentally Exposed to Supersaturated Gasses, 1996-1997 Progress Report.

This study was designed to answer the question of whether gas bubble disease (GBD) signs change as a result of the hydrostatic conditions juvenile salmonids encounter when they enter the turbine intake of hydroelectric projects during their downstream migration.
Date: March 1, 1999
Creator: Absolon, Randall F.
Object Type: Report
System: The UNT Digital Library
Analysis of heat transfer during quenching of a gear blank (open access)

Analysis of heat transfer during quenching of a gear blank

This paper presents experimental and numerical results for the quench of a gear blank in agitated and stagnant oil. Heat transfer within the gear blank is analyzed with a whole domain-optimizer technique inverse solution method, to calculate the time history at every point in the gear blank. The development of this procedure represents the first stage in an overall analysis of the quench process that will later include material phase transformations and deformation. The paper presents ten variations in setting up the inverse problem, to analyze which combination of independent variables and decision variables results in the best match between experimental and numerical results. The results indicate that dividing the boundary of the gear blank into four zones and assigning a fixed heat transfer coefficient or heat flux to each zone yields an average RMS error (average difference between experimental and numerical results) of the order of 40 K. This error can be reduced by either increasing the number of zones, by reducing the number of thermocouples being matched, or by allowing the heat transfer or heat flux to vary within the zones. Of these possibilities, variation of heat transfer within the zones gives the best improvement in the quality …
Date: March 1, 1999
Creator: Aceves, S M & Sahai, V
Object Type: Article
System: The UNT Digital Library
Evaluation of insulated pressure vessels for cryogenic hydrogen storage (open access)

Evaluation of insulated pressure vessels for cryogenic hydrogen storage

This paper presents an analytical and experimental evaluation of the applicability of insulated pressure vessels for hydrogen-fueled light-duty vehicles. Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH?) or ambient-temperature compressed hydrogen (CH2). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The purpose of this work is to verify that commercially available aluminum-lined, fiber- wrapped vessels can be used for cryogenic hydrogen storage. The paper reports on previous and ongoing tests and analyses that have the purpose of improving the system design and assure its safety.
Date: March 1, 1999
Creator: Aceves, S M; Garcia-Villazana, O & Martinez-Frias, J
Object Type: Article
System: The UNT Digital Library
An Accuracy Evaluation for the Madejski Splat-Quench Solidification Model (open access)

An Accuracy Evaluation for the Madejski Splat-Quench Solidification Model

Development of methods to spray form materials by precisely controlled deposition of droplets can result in new manufacturing processes which offer improved metallurgical performance and reduced production costs. These processes require a more detailed knowledge of the fluid mechanics, heat transfer and solidification that occur during droplet spreading. Previous work using computer simulations of this process have been difficult to implement and have required long running times. This paper examines the use of an alternative, simplified, method developed by Madjeski for solving for the problem of droplet spreading and solidification. These simplifications reduce the overall splat spreading and solidification problem to a closed-form differential equation. This differential equation is then solved under various conditions as reported from recent publications of experimental and numerical results of drop analysis. The results from the model are compared in terms of maximum spl at diameter, minimum splat thickness, and time for the droplet spreading to reach 95% of the maximum diameter. The results indicate that the accuracy of the model can be improved by accounting for energy losses in the initial rate of droplet spreading. The model results show that the predictions of experimental results are improved to within 30% over a wide range …
Date: March 1, 1999
Creator: Aceves, S. M.; Sahai, V. & Shapiro, A. B.
Object Type: Article
System: The UNT Digital Library
A new mechanical characterization method for microactuators applied to shape memory films (open access)

A new mechanical characterization method for microactuators applied to shape memory films

We present a new technique for the mechanical characterization of microactuators and apply it to shape memory alloy (SMA) thin films. A test instrument was designed which utilizes a spring-loaded transducer to measure displacements with resolution of 1.5 mm and forces with resolution of 0.2 mN. Employing an out- of-plane loading method for SMA thin films, strain resolution of 30 me and stress resolution of 2.5 MPa were achieved. Four mm long, 2 {micro}m thick NiTiCu ligaments suspended across open windows were bulk micromachined for use in the out-of-plane stress and strain measurements. Static analysis showed that 63% of the applied strain was recovered while ligaments were subjected to tensile stresses of 870 MPa. This corresponds to 280 mm of actual displacement against a load of 52 mN. Fatigue analysis of the ligaments showed 33% degradation in recoverable strain (from 0.3% to 0.2%) with 2 {+-} 10{sup 4} cycles for an initial strain of 2.8%.
Date: March 1, 1999
Creator: Ackler, H D; Krulevitch, P; Ramsey, P B & Seward, K P
Object Type: Article
System: The UNT Digital Library
National Low-Level Waste Management Program Radionuclide Report Series, Volume 17: Plutonium-239 (open access)

National Low-Level Waste Management Program Radionuclide Report Series, Volume 17: Plutonium-239

This report, Volume 17 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of plutonium-239 (Pu-239). This report also discusses waste types and forms in which Pu-239 can be found, waste and disposal information on Pu-239, and Pu-239 behavior in the environment and in the human body.
Date: March 1, 1999
Creator: Adams, J. P. & Carboneau, M. L.
Object Type: Report
System: The UNT Digital Library
National Low-Level Waste Management Program Radionuclide Report Series (open access)

National Low-Level Waste Management Program Radionuclide Report Series

The National Low Level Waste Management Program at the Idaho National Engineering and Environmental Laboratory has published a report containing key information about selected radionuclides that are most likely to contribute significantly to the radiation exposures estimated from a performance assessment of a low-level radioactive waste (LLW) disposal facility. The information includes physical and chemical characteristics, production means, waste forms, behavior of the radionuclide in soils, plants, groundwater, and air, and biological effects in animals and humans. The radionuclides included in this study comprise all of the nuclides specifically listed in 10CFR61.55, Tables 1 and 2, 3 H, 14 C, 59 Ni, 60 Co, 63 Ni, 90 Sr, 94 Nb, 99 Tc, 129 I, 137 Cs, 241 Pu, and 242 Cm. Other key radionuclides addressed in the report include 237 Np, 238 U, 239 Pu, and 241 Am. This paper summarizes key information contained within this report.
Date: March 1, 1999
Creator: Adams, James Paul; Carboneau, Michael Leonard & Allred, William Edgar
Object Type: Article
System: The UNT Digital Library
Studies of Flexible MOX/LEU Fuel Cycles (open access)

Studies of Flexible MOX/LEU Fuel Cycles

This project was a collaborative effort involving researchers from Oak Ridge National Laboratory and North Carolina State University as well as Texas A and M University. The background, briefly, is that the US is planning to use some of its excess weapons Plutonium (Pu) to make mixed-oxide (MOX) fuel for existing light-water reactors (LWRs). Considerable effort has already gone into designing fuel assemblies and core loading patterns for the transition from full-uranium cores to partial-MOX and full-MOX cores. However, these designs have assumed that any time a reactor needs MOX assemblies, these assemblies will be supplied. In reality there are many possible scenarios under which this supply could be disrupted. It therefore seems prudent to verify that a reactor-based Pu-disposition program could tolerate such interruptions in an acceptable manner. Such verification was the overall aim of this project. The task assigned to the Texas A and M team was to use the HELIOS code to develop libraries of two-group homogenized cross sections for the various assembly designs that might be used in a Westinghouse Pressurized Water Reactor (PWR) that is burning weapons-grade MOX fuel. The NCSU team used these cross sections to develop optimized loading patterns under several assumed scenarios. …
Date: March 1, 1999
Creator: Adams, M.L. & Alonso-Vargas, G.
Object Type: Report
System: The UNT Digital Library
Assessing Sources of Stress to Aquatic Ecosystems: Using Biomarkers and Bioindicators to Characterize Exodure-Response Profiles of Anthropogenic Activities (open access)

Assessing Sources of Stress to Aquatic Ecosystems: Using Biomarkers and Bioindicators to Characterize Exodure-Response Profiles of Anthropogenic Activities

Establishing causal relationships between sources of environmental stressors and aquatic ecosystem health if difficult because of the many biotic and abiotic factors which can influence or modify responses of biological systems to stress, the orders of magnitude involved in extrapolation over both spatial and temporal scales, and compensatory mechanisms such as density-dependent responses that operate in populations. To address the problem of establishing causality between stressors and effects on aquatic systems, a diagnostic approach, based on exposure-response profiles for various anthropogenic activities, was developed to help identify sources of stress responsible for effects on aquatic systems at ecological significant levels of biological organization (individual, population, community). To generate these exposure-effects profiles, biomarkers of exposure were plotted against bioindicators of corresponding effects for several major anthropogenic activities including petrochemical , pulp and paper, domestic sewage, mining operations, land-development activities, and agricultural activities. Biomarkers of exposure to environmental stressors varied depending on the type of anthropogenic activity involved. Bioindicator effects, however, including histopathological lesions, bioenergetic status, individual growth, reproductive impairment, and community-level responses were similar among many of the major anthropogenic activities. This approach is valuable to help identify and diagnose sources of stressors in environments impacted by multiple stressors. By identifying …
Date: March 29, 1999
Creator: Adams, S.M.
Object Type: Article
System: The UNT Digital Library
Treatment of solid wastes with molten salt oxidation (open access)

Treatment of solid wastes with molten salt oxidation

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Date: March 1, 1999
Creator: Adamson, M G; Ford, T D; Foster, K G; Hsu, P C; Pruneda, C O; Wallman, P H et al.
Object Type: Article
System: The UNT Digital Library
Physics-Based Damage Predictions for Simulating Testing and Evaluation (T and E) Experiments (open access)

Physics-Based Damage Predictions for Simulating Testing and Evaluation (T and E) Experiments

This is the final report of a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This report addresses the need to develop computational techniques and physics-based material models for simulating damage to weapons systems resulting from ballistic threats. Modern weapons systems, such as fighter aircraft, are becoming more dependent upon composite materials to reduce weight, to increase strength and stiffness, and to resist adverse conditions resulting from high temperatures and corrosion. Unfortunately, damaged components can have severe and detrimental effects, as evidenced by statistics from Desert Storm indicating that 75% of aircraft losses were attributable to fuel system vulnerability with hydrodynamic ram being the primary kill mechanism. Therefore, this project addresses damage predictions for composite systems that are subjected to ballistic threats involving hydrodynamic ram. A computational technique for simulating fluid-solid interaction phenomena and physics-based material models have been developed for this purpose.
Date: March 1, 1999
Creator: Addessio, Francis L.; Schraad, Mark W. & Lewis, Matthew W.
Object Type: Report
System: The UNT Digital Library
Fabrication of DDS-3, an 11.4 GHz Damped-Detuned Structure (open access)

Fabrication of DDS-3, an 11.4 GHz Damped-Detuned Structure

A 1.8 m X-band Damped-Detuned Structure (DDS-3) has been fabricated and characterized as part of the structure development program towards a TeV-scale e + e - linear collider. In this joint venture, the copper cells were precision-fabricated by LLNL, diffusion-bonded into a monolithic structure by KEK, and the structure completed and tested by SLAC. The overall process constitutes a baseline for future high-volume structure manufacture.
Date: March 1, 1999
Creator: Adolphsen, C.; Asano, K.; Elmer, J.; Funahashi, Y.; Higashi, Y.; Higo, T. et al.
Object Type: Article
System: The UNT Digital Library
Soft contributions to hard pion photoproduction (open access)

Soft contributions to hard pion photoproduction

Hard, or high transverse momentum, pion photoproduction can be a tool for probing the parton structure of the beam and target. The authors estimate the soft contributions to this process, with an eye toward delineating the region where perturbatively calculable processes dominate. Their soft process estimate is based on vector meson dominance and data based parameterizations of semiexclusive hadronic cross sections. They find that soft processes dominate in single pion photoproduction somewhat past 2 GeV transverse momentum at a few times 10 GeV incoming energy. The recent polarization asymmetry data is consistent with the perturbative asymmetry being diluted by polarization insensitive soft processes. Determining the polarized gluon distribution using hard pion photoproduction appears feasible with a few hundred GeV incoming energy (in the target rest frame).
Date: March 1, 1999
Creator: Afanasev, Andrei; Carlson, Carl E. & Wahlquist, Christian
Object Type: Article
System: The UNT Digital Library
Caribbean Basin Enhancement Legislation (open access)

Caribbean Basin Enhancement Legislation

Legislation provides Caribbean countries similar tariff benefits as Mexico under the Caribbean and Central American Relief and Economic Stabilization Act. A senate bill provides relief to the hurricane affected countries of Central America. The senate bill is more restrictive than the House bill in the scope of tariff benefits offered.
Date: March 26, 1999
Creator: Ahearn, Raymond
Object Type: Report
System: The UNT Digital Library
Current status of the recirculator project at LLNL (open access)

Current status of the recirculator project at LLNL

The Heavy Ion Fusion Group at Lawrence Livermore National Laboratory has for several years been developing the world's first circular ion induction accelerator designed to transport space charge dominated beams. Currently, the machine extends to 90 degrees, or 10 half-lattice periods (HLP) with induction cores for acceleration placed on every other HLP. Full current transport with acceptable emittance growth without acceleration has been achieved. Recently, a time stability measurement revealed a 2% energy change with time due to a source heating effect. Correcting for this and conducting steering experiments has ascertained the energy to an accuracy of 0.2%. In addition, the charge centroid is maintained to within 0.6-mm throughout the bend section. Initial studies of matches dependencies on beam quality indicate significant effects.
Date: March 23, 1999
Creator: Ahle, L; Autrey, D; Barnard, J; Craig, G; Debeling, A; Eylon, S et al.
Object Type: Article
System: The UNT Digital Library
The status of APS, BESSRC, and NEET. (open access)

The status of APS, BESSRC, and NEET.

We present a brief summary of the current status of the Advanced Photon Source (APS) at Argonne National Laboratory and of the facilities at two of the APS sectors operated by the Basic Energy Sciences Synchrotrons Radiation Center (BESSRC). This is followed by a report on recent measurements at BESSRC on the phenomenon of Nuclear Excitation by Electronic Transition (NEET).
Date: March 10, 1999
Creator: Ahmad, I.; Dunford, R. W.; Esbensen, H.; Gemmell, D. S.; Kanter, E. P.; Kraessig, B. et al.
Object Type: Article
System: The UNT Digital Library
High Intensity Performance of the Brookhaven AGS. (open access)

High Intensity Performance of the Brookhaven AGS.

The Brookhaven AGS provides 24 GeV protons for a multi-user program of fixed-target high energy physics experiments, such as the study of extremely rare Kaon decays. Up to 7 x 10{sup 13} protons are slowly extracted over 2.2 seconds each 5.1 seconds. The muon storage ring of the g-2 experiment is supplied with bunches of 7 x 10{sup 12} protons. Since the completion of the a 1.9 GeV Booster synchrotron and installation of a new high-power rf system and transition jump system in the AGS various modes of operation have been explored to overcome space charge limits and beam instabilities at these extreme beam intensities. Experiments have been done using barrier cavities to enable accumulation of debunched beam in the AGS as a potential path to significantly higher intensities. We report on the present understanding of intensity limitations and prospects for overcoming them.
Date: March 29, 1999
Creator: Ahrens, L. A.; Alessi, J.; Blaskiewicz, M.; Brennan, J. M.; Brown, K.; Gardner, C. et al.
Object Type: Article
System: The UNT Digital Library
Performance of the AGS Transition Jump System. (open access)

Performance of the AGS Transition Jump System.

The transition jump system has been indispensable to the high intensity proton operation of the AGS complex. Nevertheless, transition crossing remains one of the major hurdles as the accelerator complex intensity is pushed upward. To enhance the performance of the system ''quadrupole pumping'' in the Booster is used to minimize the necessary longitudinal dilution of the beam on the AGS injection porch. During the transition jump sextupole correctors at strategic locations are pulsed to minimize the effects of the chromatic non-linearity of the jump system. The available instrumentation for diagnosing the performance of the system will be described, along with installed hardware to counter the non-linear effects of the transition jump system.
Date: March 29, 1999
Creator: Ahrens, L. A.; Brennan, J. M.; Glenn, J. W.; Roser, T. & Van Asselt, W. K.
Object Type: Article
System: The UNT Digital Library
AGS Resonant Extraction With High Intensity Beams. (open access)

AGS Resonant Extraction With High Intensity Beams.

The Brookhaven AGS third integer resonant extraction system allows the AGS to provide high quality, high intensity 25.5 GeV/c proton beams simultaneously to four target stations and as many as 8 experiments. With the increasing intensities (over 7 x 10{sup 13} protons/pulse) and associated longer spill periods (2.4 to 3 seconds long), we continue to run with low losses and high quality low modulation continuous current beams.[1] Learning to extract and transport these higher intensity beams has required a process of careful modeling and experimentation. We have had to learn how to correct for various instabilities and how to better match extraction and the transport lines to the higher emittance beams being accelerated in the AGS. Techniques employed include ''RF'' methods to smooth out momentum distributions and fine structure. We will present results of detailed multi-particle tracking modeling studies which enabled us to develop a clear understanding of beam loss mechanisms in the transport and extraction process. We will report on our status, experiences, and the present understanding of the intensity limitations imposed by resonant extraction and transport to fixed target stations.
Date: March 29, 1999
Creator: Ahrens, L.; Brown, K.; Glenn, J. W.; Roser, T.; Tsoupas, N. & Vanasselt, W.
Object Type: Article
System: The UNT Digital Library
Investigation of mixed metal sorbent/catalysts for the simultaneous removal of sulfur and nitrogen oxides (open access)

Investigation of mixed metal sorbent/catalysts for the simultaneous removal of sulfur and nitrogen oxides

Simultaneous removal of SO{sub 2} and NO{sub x} using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO{sub 2} and NO{sub x} removal operations. The work done at PETC and the DOE-funded investigation of the investigators on the sulfation and regeneration of alumina-supported cerium oxide sorbents have shown that they can perform well at relatively high temperatures (823-900 K) as regenerable desulfurization sorbents. Survey of the recent literature shows that addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K, sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures, SO{sub 2} can be directly reduced to sulfur by CO on CuO-ceria catalysts, and ceria-based catalysts may have a potential for selective catalytic reduction of NO{sub x} by methane. These observations indicate a possibility of developing a ceria-based sorbent/catalyst which can remove both SO{sub 2} and NO{sub x} from flue gases within a relatively wide temperature window, produce significant amounts of elemental sulfur during regeneration, and use methane for the selective catalytic reduction of NO{sub x}. …
Date: March 31, 1999
Creator: Akyurtlu, A. & Akyurtlu, J.F.
Object Type: Report
System: The UNT Digital Library
Chemometric Analysis of Two Dimensional Decay Data: Application to {sup 17}O NMR Relaxation Matrices (open access)

Chemometric Analysis of Two Dimensional Decay Data: Application to {sup 17}O NMR Relaxation Matrices

The use of {sup 17}O NMR spectroscopy as a tool to investigate aging in polymer systems has recently been demonstrated. Because the natural abundance of {sup 17}O is extremely low (0.037%), the use of labeled {sup 17}O{sub 2} during the oxidation of polymers produces {sup 17}O NMR spectra whose signals arise entirely from the degradation species (i.e. signals from the bulk or unaged material are not observed). This selective isotopic labeling eliminates the impact of interference from the unaged material, cause (1) above. As discussed by Alam et al. spectral overlap between different degradation species as well as errors in quantification remains a major difficulty in {sup 17}O NMR spectroscopy. As a demonstration of the DECRA and CTBSA methods, relaxation matrices obtained from {sup 17}O NMR for model alcohol systems are evaluated. The benefits and limitations of these newly developed chemometric techniques are discussed.
Date: March 18, 1999
Creator: Alam, M. K. & Alam, T. M.
Object Type: Article
System: The UNT Digital Library
An x-ray fluorescence study of lake sediments from ancient Turkey using synchrotron radiation. (open access)

An x-ray fluorescence study of lake sediments from ancient Turkey using synchrotron radiation.

Sediments from relic Lake Golbasi were analyzed by X-ray fluorescence with synchrotrons radiation to determine changes in element concentrations over time with selected elements serving as proxies for environmental change. Increases in Ca and Sr suggest soil formation during a dry period, from ca. 4500 BC to ca. 200 AD at which point K, Rb, Zr, Ti, and Y increase, indicating the return of a wet environment. Soil erosion, represented by Cr and Ni, increases ca. 7000 BC, probably as a consequence of environmental change, prior to suggested exploitation of natural resources by the newly urbanized society of the third millennium BC.
Date: March 10, 1999
Creator: Alatas, A.; Alp, E. E.; Friedman, E. S.; Jennings, G.; Johnson, C. E.; Lai, B. et al.
Object Type: Article
System: The UNT Digital Library