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3-D research transport codes at Los Alamos (open access)

3-D research transport codes at Los Alamos

We describe 3-D research transport codes which have been developed at Los Alamos National Laboratory over the last three years. Some simple example calculations are presented.
Date: October 1, 1994
Creator: Morel, J. E.; McGhee, J. M. & Walters, W. F.
Object Type: Article
System: The UNT Digital Library
A 3-D time-dependent unstructured tetrahedral-mesh SP{sub N} method (open access)

A 3-D time-dependent unstructured tetrahedral-mesh SP{sub N} method

We have developed a 3-D time-dependent multigroup SP{sub n} method for unstructured tetrahedral meshes. The SP{sub n} equations are expressed in a canonical form which allows them to be solved using standard diffusion solution techniques in conjunction with source iteration, diffusion-synthetic acceleration, and fission-source acceleration. A computational comparison of our SP{sub n} method with an even-parity S{sub n} method is given.
Date: October 1, 1994
Creator: Morel, J. E.; McGhee, J. M. & Larsen, E. W.
Object Type: Article
System: The UNT Digital Library
216-B-3 expansion ponds closure plan (open access)

216-B-3 expansion ponds closure plan

This document describes the activities for clean closure under the Resource Conservation and Recovery Act of 1976 (RCRA) of the 216-B-3 Expansion Ponds. The 216-B-3 Expansion Ponds are operated by the US Department of Energy, Richland Operations Office (DOE-RL) and co-operated by Westinghouse Hanford Company (Westinghouse Hanford). The 216-B-3 Expansion Ponds consists of a series of three earthen, unlined, interconnected ponds that receive waste water from various 200 East Area operating facilities. The 3A, 3B, and 3C ponds are referred to as Expansion Ponds because they expanded the capability of the B Pond System. Waste water (primarily cooling water, steam condensate, and sanitary water) from various 200 East Area facilities is discharged to the Bypass pipe (Project X-009). Water discharged to the Bypass pipe flows directly into the 216-B-3C Pond. The ponds were operated in a cascade mode, where the Main Pond overflowed into the 3A Pond and the 3A Pond overflowed into the 3C Pond. The 3B Pond has not received waste water since May 1985; however, when in operation, the 3B Pond received overflow from the 3A Pond. In the past, waste water discharges to the Expansion Ponds had the potential to have contained mixed waste (radioactive waste …
Date: October 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
300 Area treated effluent disposal facility operating specifications document (open access)

300 Area treated effluent disposal facility operating specifications document

These specifications deal with the release of treated water into the Columbia River via the TEDF submerged outfall. Specific limits are set for contaminants to be discharged in NPDES permit WA-002591-7. This section contains the operating ranges that will be used to best meet the permit limits.
Date: October 1, 1994
Creator: Olander, A. R.
Object Type: Report
System: The UNT Digital Library
A 500 MW annular beam relativistic klystron (open access)

A 500 MW annular beam relativistic klystron

This paper describes the experimental development of a long pulse, high current, annular beam relativistic klystron amplifier. The desired performance parameters are 1 GW output power and 1 {mu}s pulse length with an operating frequency of 1.3 GHz. The electron beam voltage and current are nominally 600 kV and 5 kA. Peak powers approaching 500 MW have been achieved in pulses of 1 {mu}s nominal baseline-to-baseline duration. The half power pulse width is 0.5 {mu}s. These pulses contain an energy of about 160 J. The design of this class of tube presents some unique challenges, particularly in the output cavity. The output cavity must exhibit a very low gap shunt impedance in order to obtain reasonable conversion efficiency from the low impedance modulated electron beam to microwave power, while still maintaining a reasonable loaded Q for mode purity. The physics of this device is dominated by space charge effects which strongly impact the design. Current experimental results and theoretical design considerations for this class of tube, and scaling to higher frequency operation, suitable for the Next Linear Collider are discussed.
Date: October 1, 1994
Creator: Fazio, Michael V.; Haynes, W. Brian; Carlsten, Bruce E. & Stringfield, Ray M.
Object Type: Article
System: The UNT Digital Library
89C-GEB-610 PFP instrument upgrade functional test procedure (open access)

89C-GEB-610 PFP instrument upgrade functional test procedure

This document, Functional Test Procedure (TP), has been prepared to demonstrate that the Instrumentation Upgrade functions as required by Project criteria.
Date: October 1, 1994
Creator: Shank, D. R.
Object Type: Report
System: The UNT Digital Library
Abbreviated sampling and analysis plan for planning decontamination and decommissioning at Test Reactor Area (TRA) facilities (open access)

Abbreviated sampling and analysis plan for planning decontamination and decommissioning at Test Reactor Area (TRA) facilities

The objective is to sample and analyze for the presence of gamma emitting isotopes and hazardous constituents within certain areas of the Test Reactor Area (TRA), prior to D and D activities. The TRA is composed of three major reactor facilities and three smaller reactors built in support of programs studying the performance of reactor materials and components under high neutron flux conditions. The Materials Testing Reactor (MTR) and Engineering Test Reactor (ETR) facilities are currently pending D/D. Work consists of pre-D and D sampling of designated TRA (primarily ETR) process areas. This report addresses only a limited subset of the samples which will eventually be required to characterize MTR and ETR and plan their D and D. Sampling which is addressed in this document is intended to support planned D and D work which is funded at the present time. Biased samples, based on process knowledge and plant configuration, are to be performed. The multiple process areas which may be potentially sampled will be initially characterized by obtaining data for upstream source areas which, based on facility configuration, would affect downstream and as yet unsampled, process areas. Sampling and analysis will be conducted to determine the level of gamma …
Date: October 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Accelerator-driven molten-salt blankets: Physics issues (open access)

Accelerator-driven molten-salt blankets: Physics issues

A number of nuclear physics issues concerning the Los Alamos molten-salt accelerator-driven plutonium converter are discussed. General descriptions of several concepts using internal and external moderation are presented. Burnup and salt processing requirement calculations are presented for four concepts, indicating that both the high power density externally moderated concept and an internally moderated concept achieve total plutonium burnups approaching 90% at salt processing rates of less than 2 m{sup 3} per year. Beginning-of-life reactivity temperature coefficients and system kinetic response are also discussed. Future research should investigate the effect of changing blanket composition on operational and safety characteristics.
Date: October 1, 1994
Creator: Houts, M. G.; Beard, C. A.; Buksa, J. J.; Davidson, J. W.; Durkee, J. W.; Perry, R. T. et al.
Object Type: Article
System: The UNT Digital Library
Acceptance of feed streams for treatment at the LERF/ETF complex (open access)

Acceptance of feed streams for treatment at the LERF/ETF complex

None
Date: October 1, 1994
Creator: McDonald, F. N.
Object Type: Report
System: The UNT Digital Library
Acceptance/operational test procedure 101-SY tank camera purge system and in tank color camera video imaging system (open access)

Acceptance/operational test procedure 101-SY tank camera purge system and in tank color camera video imaging system

This Acceptance/Operational Test Procedure will document the satisfactory operation of the 101-SY color camera purge control system and color camera video imaging system.
Date: October 1, 1994
Creator: Werry, S. M.
Object Type: Report
System: The UNT Digital Library
Accepting the T3D (open access)

Accepting the T3D

In April, a 128 PE Cray T3D was installed at Los Alamos National Laboratory`s Advanced Computing Laboratory as part of the DOE`s High-Performance Parallel Processor Program (H4P). In conjunction with CRI, the authors implemented a 30 day acceptance test. The test was constructed in part to help them understand the strengths and weaknesses of the T3D. In this paper, they briefly describe the H4P and its goals. They discuss the design and implementation of the T3D acceptance test and detail issues that arose during the test. They conclude with a set of system requirements that must be addressed as the T3D system evolves.
Date: October 1, 1994
Creator: Rich, D. O.; Pope, S. C. & DeLapp, J. G.
Object Type: Article
System: The UNT Digital Library
Activation concentrations outside the SSC accelerator enclosures (open access)

Activation concentrations outside the SSC accelerator enclosures

Activation of groundwater due to beam loss at the Superconducting Super Collider (SSC) is discussed, with activation criteria and models presented. Estimates are given of maximum beam losses allowed in the various accelerators of the SSC to meet federal drinking water standards, assuming no additional shielding is provided.
Date: October 1, 1994
Creator: Baker, S.; Bull, J. & Stapleton, G.
Object Type: Report
System: The UNT Digital Library
Adaptive measurement control for calorimetric assay (open access)

Adaptive measurement control for calorimetric assay

The performance of a calorimeter is usually evaluated by constructing a Shewhart control chart of its measurement errors for a collection of reference standards. However, Shewhart control charts were developed in a manufacturing setting where observations occur in batches. Additionally, the Shewhart control chart expects the variance of the charted variable to be known or at least well estimated from previous experimentation. For calorimetric assay, observations are collected singly in a time sequence with a (possibly) changing mean, and extensive experimentation to calculate the variance of the measurement errors is seldom feasible. These facts pose problems in constructing a control chart. In this paper, the authors propose using the mean squared successive difference to estimate the variance of measurement errors based solely on prior observations. This procedure reduces or eliminates estimation bias due to a changing mean. However, the use of this estimator requires an adjustment to the definition of the alarm and warning limits for the Shewhart control chart. The authors propose adjusted limits based on an approximate Student`s t-distribution for the measurement errors and discuss the limitations of this approximation. Suggestions for the practical implementation of this method are provided also.
Date: October 1, 1994
Creator: Glosup, J. G. & Axelrod, M. C.
Object Type: Article
System: The UNT Digital Library
Adsorption Decontamination of Radioactive Waste Solvent by Activated Alumina and Bauxites (open access)

Adsorption Decontamination of Radioactive Waste Solvent by Activated Alumina and Bauxites

An adsorption process utilizing activated alumina and activated bauxite adsorbents was evaluated as a function of operating parameters for the removal of low level radioactive contaminants from organic waste solvent generated in the fuel reprocessing facilities and support operations at Savannah River Site. The waste solvent, 30% volume tributyl phosphate in n-paraffin diluent, was degraded due to hydrolysis and radiolysis reactions of tributyl phosphate and n-paraffin diluent, producing fission product binding degradation impurities. The process, which has the potential for removing these activity-binding degradation impurities from the solvent, was operated downflow through glass columns packed with activated alumina and activated bauxite adsorbents. Experimental breakthrough curves were obtained under various operating temperatures and flow rates. The results show that the adsorption capacity of the activated alumina was in the order 10{sup 4} dpm/g and the capacity of the activated bauxite was 10{sup 5} dpm/g. The performance of the adsorption process was evaluated in terms of dynamic parameters (i.e. adsorption capacity, the height and the efficiency of adsorption zone) in such a way as to maximize the adsorption capacity and to minimize the height of the mass transfer or adsorption zone.
Date: October 1, 1994
Creator: Hassan, N. M.; Marra, J. C. & Kyser, E. A.
Object Type: Report
System: The UNT Digital Library
Adsorption of hydrogen sulfide by zinc ferrite in the temperature range 315 to 538 C (600 to 1,000 F) (open access)

Adsorption of hydrogen sulfide by zinc ferrite in the temperature range 315 to 538 C (600 to 1,000 F)

The high-temperature, regenerable, desulfurization sorbents under development at METC for use in advanced power systems incorporating coal gasification have been designed to operate at temperatures upwards of about 538 C (1,000 F). This temperature has been thought to be optimal, taking into account such factors as higher sorbent reactivity, increased thermodynamic efficiency, and regeneration temperature. Recent revision of total system considerations indicates that, in certain circumstances, it may be desirable to operate these sorbents at lower temperatures because of materials considerations. Therefore, a small laboratory investigation of the desulfurization performance of zinc ferrite, one of the sorbents under development, was conducted in the temperature range 315 to 538 C. Reduction of zinc ferrite (i.e., ZnFe{sub 2}O{sub 4} {yields} Fe{sub 3}O{sub 4} + ZnO) is necessary for good desulfurization; reduction caused formation of zinc oxide and magnetite of smaller crystallite size than original zinc ferrite; reduction of zinc ferrite caused a significant increase in small pore porosity; and zinc ferrite can be used below 538 C (1,000 F) if an initial reduction is carried out.
Date: October 1, 1994
Creator: Grindley, Thomas
Object Type: Report
System: The UNT Digital Library
An advanced ECR ion source with a large uniformly distributed ECR plasma volume for multiply charged ion beam generation (open access)

An advanced ECR ion source with a large uniformly distributed ECR plasma volume for multiply charged ion beam generation

A new ECR ion source geometry has been conceived which uses a minimum-B magnetic mirror geometry consisting of a multi-cusp, magnetic field, to assist in confining the plasma radially, a flat central field for tuning to the ECR resonant condition, and specially tailored mirror fields in the end zones for confining the plasma in the axial direction. The magnetic field, designed to achieve an axially symmetric plasma ``volume`` with constant mod-B, extends over the length of the central field region. This design, which strongly contrasts with ``surface`` ECR zones characteristic of conventional ECR ion sources, results in dramatic increases in the adsorption of RF power, thereby increasing the electron temperature and ``hot`` electron population within the ionization volume of the source. The ECR zone is concentrated symmetrically around the axis of symmetry and along the length of the plasma volume rather than in thin surface layers located off-axis as is the case in conventional ECR ion sources. The creation of a ``volume`` rather than a ``surface`` ECR zone and its distribution relative to the optical axis where the ions of interest are extracted is commensurate with the generation of higher beam intensities, higher charge states and a higher degree of …
Date: October 1, 1994
Creator: Alton, G. D. & Smithe, D. N.
Object Type: Article
System: The UNT Digital Library
Advanced Reflector Materials for Solar Concentrators (open access)

Advanced Reflector Materials for Solar Concentrators

This paper describes the research and development program at the U.S. National Renewable Energy Laboratory (NREL) in advanced reflector materials for solar concentrators. NREL's research thrust is to develop solar reflector materials that maintain high specular reflectance for extended lifetimes under outdoor service conditions and whose cost is significantly lower than existing products. Much of this work has been in collaboration with private-sector companies that have extensive expertise in vacuum-coating and polymer-film technologies. Significant progress and other promising developments will be discussed. These are expected to lead to additional improvements needed to commercialize solar thermal concentration systems and make them economically attractive to the solar manufacturing industry. To explicitly demonstrate the optical durability of candidate reflector materials in real-world service conditions, a network of instrumented outdoor exposure sites has been activated.
Date: October 1, 1994
Creator: Jorgensen, Gary; Williams, Tom & Wendelin, Tim
Object Type: Article
System: The UNT Digital Library
Advanced robotic technologies for transfer at Sandia National Laboratories (open access)

Advanced robotic technologies for transfer at Sandia National Laboratories

Hazardous operations which have in the past been completed by technicians are under increased scrutiny due to high costs and low productivity associated with providing protective clothing and environments. As a result, remote systems are needed to accomplish many hazardous materials handling tasks such as the clean-up of waste sites in which the exposure of personnel to radiation, chemical, explosive and other hazardous constituents is unacceptable. Computer models augmented by sensing, and structured, modular computing environments are proving effective in automating many unstructured hazardous tasks. Work at Sandia National Laboratories (SNL) has focused on applying flexible automation (robotics) to meet the needs of the U.S. Department of Energy (USDOE). Dismantling facilities, environmental remediation, and materials handling in changing, hazardous environments lead to many technical challenges. Computer planning, monitoring and operator assistance shorten training cycles, reduce errors, and speed execution of operations. Robotic systems that re-use well-understood generic technologies can be much better characterized than robotic systems developed for a particular application, leading to a more reliable and safer systems. Further safety in robotic operations results from use of environmental sensors and knowledge of the task and environment. Collision detection and avoidance is achieved from such sensor integration and model-based control. …
Date: October 1, 1994
Creator: Bennett, P. C.
Object Type: Article
System: The UNT Digital Library
Advanced sulfur control concepts in hot-gas desulfurization technology: Phase 1, Feasibility of the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents (open access)

Advanced sulfur control concepts in hot-gas desulfurization technology: Phase 1, Feasibility of the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents

This topical report de-scribes the results of Phase 1 research performed during the first six months of a three-year contract to study the feasibility of the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents. Much effort has gone into the development of a high-temperature meal oxide sorbent process for removal of H{sub 2}S from the coal gas. A number of sorbents based upon metals such as zinc, iron, manganese and others have been studied. In order for high temperature desulfurization to be economical it is necessary that the sorbents be regenerated to permit multicycle operation. Current methods of sorbent regeneration involve oxidation of the metal sulfide to reform the metal oxide and free the sulfur as SO{sub 2}. An alternate regeneration process in which the sulfur is liberated in elemental form is preferable. The overall objective of the current research is to study simpler and economically superior processing of known sorbents capable of producing elemental sulfur during regeneration. This topical report summarizes the first steps of this effort. A literature search has been completed to identify possible regeneration concepts and to collect relevant thermodynamic, kinetic, and process data. Three concepts involving reaction with SO{sub 2}, …
Date: October 1, 1994
Creator: Lopez, A.; White, J.; Groves, F. R. & Harrison, D. P.
Object Type: Report
System: The UNT Digital Library
Advanced turbine systems program conceptual design and product development. Annual report, August 1994--July 1995 (open access)

Advanced turbine systems program conceptual design and product development. Annual report, August 1994--July 1995

Objective of the ATS program is to develop ultra-high efficiency, environmentally superior, and cost-competitive gas turbine systems for base-load application in utility, independent power producer, and industrial markets. This report discusses the major accomplishments achieved during the second year of the ATS Phase 2 program, particularly the design and test of critical components.
Date: October 1, 1994
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advanced turbine systems program overview (open access)

Advanced turbine systems program overview

The US Department of Energy`s (DOE) Office of Fossil Energy and Office of Energy Efficiency & Renewable Energy are jointly supporting a program to develop Advanced Turbine Systems (ATS). Demonstrations of commercial prototypes will be completed by the year 2000 for both utility- and industrial-scale applications. The program is primarily directed toward natural gas utilization, but eventual application of the technology to coal-fired systems is not overlooked. In major procurements, contractors are required to address (in paper studies though not in testing) the eventual adaptation of their systems to coal firing. Implementation of the program is proceeding well. Phase 1 systems studies have been completed, and Phase 2 concept development has been underway for about a year. Release of solicitation for Phase 3 proposals has been announced for July, 1994. This phase of the program will see teams led by turbine manufacturers move into full scale testing of critical components. Generic research and development has been proceeding in parallel with the major development effort. METC has started testing in their Advanced Turbine Combustion test facility, and Oak Ridge National Laboratory has initiated a materials test program. The industry/university consortium established by the South Carolina Energy Research and Development Center has …
Date: October 1, 1994
Creator: Webb, H. A.
Object Type: Article
System: The UNT Digital Library
Advancing PET science for new measures of brain function. Progress report, January 1, 1994--December 31, 1994 (open access)

Advancing PET science for new measures of brain function. Progress report, January 1, 1994--December 31, 1994

This project has continued the development of new chemistry and imaging physics applicable to PET studies of the human brain. In basic radiochemistry research, the authors have developed a modified approach to solid-phase supported [{sup 11}C]methylation system, in part dependent on the design, fabrication and validation of new small, sensitive and accurate positron detectors useful in tracking the flow of radioactivity through the synthesis apparatus. Radiopharmaceutical efforts have resulted in synthesis of new tracers of mitochondrial enzymes. For evaluation of new PET radiotracers, the authors have applied new models of unilateral brain lesions using quinolinic acid and MPP+, as models of neurodegenerative diseases. In the physics and data analysis research area the authors have developed faster and more accurate means of performing image reconstruction for use with both emission and transmission data. The authors are optimizing acquisition and kinetic modeling strategies for new radiotracers. The authors also have implemented and proven the utility of performing task switching during PET CBF activation studies for the purpose of enhancing signal-to-noise and greater detectability of areas of activation. The authors also working on routines for standardization of analysis strategies for group vs. group and individual vs. group comparisons.
Date: October 1, 1994
Creator: Kuhl, D. E.
Object Type: Report
System: The UNT Digital Library
Adventures in supercomputing, a K-12 program in computational science: An assessment (open access)

Adventures in supercomputing, a K-12 program in computational science: An assessment

In this paper, the authors describe only those elements of the Department of Energy Adventures in Supercomputing (AiS) program for high school teachers, such as school selection, which have a direct bearing on assessment. Schools submit an application to participate in the AiS program. They propose a team of at least two teachers to implement the AiS curriculum. The applications are evaluated by selection committees in each of the five participating states to determine which schools are the most qualified to carry out the program and reach a significant number of women, minorities, and economically disadvantaged students, all of whom have historically been underrepresented in the sciences. Typically, selected schools either have a large disadvantaged student population, or the applying teachers propose specific means to attract these segments of their student body into AiS classes. Some areas with AiS schools have significant numbers of minority students, some have economically disadvantaged, usually rural, students, and all areas have the potential to reach a higher proportion of women than technical classes usually attract. This report presents preliminary findings based on three types of data: demographic, student journals, and contextual. Demographic information is obtained for both students and teachers. Students have been asked …
Date: October 1, 1994
Creator: Oliver, C. E.; Hicks, H. R.; Iles-Brechak, K. D.; Honey, M. & McMillan, K.
Object Type: Article
System: The UNT Digital Library
Aerogels for electronics (open access)

Aerogels for electronics

In addition to their other exceptional properties, aerogels also exhibit unusual dielectric and electronic properties due to their nano-sized structures and high porosities. For example, aerogels have the lowest dielectric constants measured for a solid material (having values approaching 1.0); they have exceptionally high dielectric resistivities and strengths (i.e., ability to insulate very high voltages); they exhibit low dielectric loss at microwave frequencies; and some aerogels are electrically conductive and photoconductive. These properties are being exploited to provide the next generation of materials for energy storage, low power consumption, and ultra-fast electronics. We are working toward adapting these unusual materials for microelectronic applications, particularly, making thin aerogel films for dielectric substrates and for energy storage devices such as supercapacitors. Measurements are presented in this paper for the dielectric and electronic properties of aerogels, including the dielectric constant, loss factor, dielectric and electrical conductivity, volume resistivity, and dielectric strength. We also describe methods to form and characterize thin aerogel films which are being developed for numerous electronic applications. Finally, some of the electronic applications proposed for aerogels are presented. Commercialization of aerogels for electronics must await further feasibility, prototype development, and cost studies, but they are one of the key materials …
Date: October 1, 1994
Creator: Hrubesh, L. W.
Object Type: Article
System: The UNT Digital Library