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1990 fuel cell seminar: Program and abstracts (open access)

1990 fuel cell seminar: Program and abstracts

This volume contains author prepared short resumes of the presentations at the 1990 Fuel Cell Seminar held November 25-28, 1990 in Phoenix, Arizona. Contained herein are 134 short descriptions organized into topic areas entitled An Environmental Overview, Transportation Applications, Technology Advancements for Molten Carbonate Fuel Cells, Technology Advancements for Solid Fuel Cells, Component Technologies and Systems Analysis, Stationary Power Applications, Marine and Space Applications, Technology Advancements for Acid Type Fuel Cells, and Technology Advancement for Solid Oxide Fuel Cells.
Date: December 31, 1990
Creator: unknown
System: The UNT Digital Library
A 2D electrostatic PIC code for the Mark III Hypercube (open access)

A 2D electrostatic PIC code for the Mark III Hypercube

We have implemented a 2D electrostastic plasma particle in cell (PIC) simulation code on the Caltech/JPL Mark IIIfp Hypercube. The code simulates plasma effects by evolving in time the trajectories of thousands to millions of charged particles subject to their self-consistent fields. Each particle`s position and velocity is advanced in time using a leap frog method for integrating Newton`s equations of motion in electric and magnetic fields. The electric field due to these moving charged particles is calculated on a spatial grid at each time by solving Poisson`s equation in Fourier space. These two tasks represent the largest part of the computation. To obtain efficient operation on a distributed memory parallel computer, we are using the General Concurrent PIC (GCPIC) algorithm previously developed for a 1D parallel PIC code.
Date: December 31, 1990
Creator: Ferraro, R. D.; Liewer, P. C. & Decyk, V. K.
System: The UNT Digital Library
Access and Use of Information Resources in Assessing Health Risks From Chemical Exposure: Proceedings (open access)

Access and Use of Information Resources in Assessing Health Risks From Chemical Exposure: Proceedings

Health risk assessment is based on access to comprehensive information about potentially hazardous agents in question. Relevant information is scattered throughout the literature, and often is not readily accessible. To be useful in assessment efforts, emerging scientific findings, risk assess parameters, and associated data must be compiled and evaluated systemically. The US Environmental Protection Agency (EPA) and Oak Ridge National Laboratory (ORNL) are among the federal agencies heavily involved in this effort. This symposium was a direct response by EPA and ORNL to the expressed needs of individuals involved in assessing risks from chemical exposure. In an effort to examine the state of the risk assessment process, the availability of toxicological information, and the future development and transfer of this information, the symposium provided an excellent cadre of speakers and participants from state and federal agencies, academia and research laboratories to address these topics. This stimulating and productive gathering discussed concerns associated with (1) environmental contamination by chemicals; (2) laws regulating chemicals; (3) information needs and resources; (4) applications; (5) challenges and priorities; and (6)future issues. Individual reports are processed separately for the data bases.
Date: December 31, 1990
Creator: unknown
System: The UNT Digital Library
[ACEEE summer study on energy efficiency in buildings]. Final technical report (open access)

[ACEEE summer study on energy efficiency in buildings]. Final technical report

The ACEEE Summer Study is a biennial conference that aims to bring together the foremost researchers, practitioners and policy makers involved in research on energy efficiency in buildings. The 1990 Summer Study had the objective to facilitate the exchange of research and implementation results and encourage the advancement of knowledge in the field of energy efficiency in buildings. The research papers presented at the conference published and distributed. Two hundred seventy two papers were presented. These individual papers, published in ten volumes, have been processed separately for the Energy Data Base.
Date: December 31, 1990
Creator: unknown
System: The UNT Digital Library
Advanced radioactive waste-glass melters (open access)

Advanced radioactive waste-glass melters

During pilot scale operations of the Scale Glass Melter for the US Department of Energy a team of engineers and scientists was formed to assess the need for continued melter design development to support the Defense Waste Processing Facility (DWPF), and prioritize future efforts. Recently this has taken on new importance because of selection of the DWPF Melter design as the reference for the Hanford Waste Vitrification Project (HWVP), and increased interest at the West Valley Demonstration Project on melter life and replacement. Results of the study are summarized, and goals produced by the study are compared to the results of current programs at the Savannah River Laboratory (SRL).
Date: December 31, 1990
Creator: Bickford, D. F.
System: The UNT Digital Library
The advantages of a salt/bentonite backfill for Waste Isolation Pilot Plant disposal rooms (open access)

The advantages of a salt/bentonite backfill for Waste Isolation Pilot Plant disposal rooms

This paper concludes that a 70/30 wt % salt/bentonite mixture is preferable to pure crushed salt as backfill for disposal rooms in the Waste Isolation Pilot Plant. The Waste Isolation Pilot Plant, near Carlsbad, NM, is designed to be the first mined geologic repository for the safe disposal of transuranic (TRU) radioactive waste generated by DOE defense programs since 1970. The repository is located about 655 m below the land surface in an extensive bedded salt formation. This report examines the performance of two backfill materials with regard to various selection criteria, such as the need for low permeability after closure, chemical stability, strength, ease of emplacement, and sorption potential for brine and radionuclides. Both salt and salt/bentonite are expected to consolidate to a state of permeability {le} 10{sup {minus}18} m{sup 2} that is adequate for satisfying regulations for nuclear repositories. The results of finite-element calculations that were used to arrive at this conclusion will be described. The real advantage of the salt/bentonite. backfill depends, therefore, on bentonite`s potential for sorbing brine and radionuclides. Estimates of the impact of these properties on backfill performance are presented.
Date: December 31, 1990
Creator: Butcher, B. M.
System: The UNT Digital Library
Altered phenotypes in plants transformed with chimeric tobacco peroxidase genes (open access)

Altered phenotypes in plants transformed with chimeric tobacco peroxidase genes

Peroxidases have been implicated in a variety of secondary metabolic reactions including lignification, cross-linking of cell wall polysaccharides, oxidation of indole-3-acetic acid, regulation of cell elongation, wound-healing, phenol oxidation, and pathogen defense. However, due to the many different isoenzymes and even more potential substrates, it has proven difficult to verify actual physiological roles for peroxidase. We are studying the molecular biology of the tobacco peroxidase genes, and have utilized genetic engineering techniques to produce transgenic plants which differ only in their expression of an individual peroxidase isoenzyme. Many of the in planta functions for any individual isoenzyme may be predicted through the morphological and physiological analysis of transformed plants.
Date: December 31, 1990
Creator: Lagrimini, L. M.
System: The UNT Digital Library
An analysis of heating and cooling conservation features in commercial buildings (open access)

An analysis of heating and cooling conservation features in commercial buildings

One purpose of this study is to estimate the relationship in commercial buildings between conservation investments, fuel prices, building occupancy and building characteristics for new buildings and for existing buildings. The database is a nationwide survey of energy in commercial buildings conducted by the Energy Information Administration (EIA) in 1906. Some simple cross-tabulations indicate that conservation measures vary with building size, building age, and fuel used for building heating. Regression estimates of a conservation model indicate that the number of conservation model indicate that the number of conservation features installed during construction is a positive function of the price of the heating fuel at the time of construction. Subsequent additions of conservation features are positively correlated with increases in heating fuel prices. Given the EIA projection of relatively stable future energy prices, the number of retrofits may not increase significantly. Also, energy efficiency in new buildings may not continue to increase relative to current new buildings. If fuel prices affect consumption via initial conservation investments, current fuel prices, marginal or average, are not the appropriate specification. The fuel price regression results indicate that conservation investments in new buildings are responsive to market signals. Retrofits are less responsive to market signals. …
Date: December 31, 1990
Creator: Sutherland, R. J.
System: The UNT Digital Library
Analytical mass spectrometry. Abstracts (open access)

Analytical mass spectrometry. Abstracts

This 43rd Annual Summer Symposium on Analytical Chemistry was held July 24--27, 1990 at Oak Ridge, TN and contained sessions on the following topics: Fundamentals of Analytical Mass Spectrometry (MS), MS in the National Laboratories, Lasers and Fourier Transform Methods, Future of MS, New Ionization and LC/MS Methods, and an extra session. (WET)
Date: December 31, 1990
Creator: unknown
System: The UNT Digital Library
Application of hydration thermodynamics to control of the DWPF process. Revision 1 (open access)

Application of hydration thermodynamics to control of the DWPF process. Revision 1

The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) will incorporate the radioactivity in the 130 million liters of high-level nuclear waste at SRS in a stable borosilicate glass. Glass product specifications requite control of processing parameters to ensure glass durability. A model of glass durability, based on hydration thermodynamics, has been used at SRS to aid in formulation of waste glasses; to explain the relative durability of different glasses under identical test conditions (MCC-1 test ); and to explain the effects of changing test conditions on the observed durability of a given glass. This model has now been modified for use in control of the DWPF. It provides a tool which relates glass durability to parameters which can be controlled in the DWPF process. It provides a tool which relates glass durability to parameters which can be controlled in the DWPF process, primarily chemical composition. In this paper, the model is presented, and its projected role in control of the DWPF process is described.
Date: December 31, 1990
Creator: Plodinec, M. J.
System: The UNT Digital Library
Applications of neural networks to monitoring and decision making in the operation of nuclear power plants. Summary (open access)

Applications of neural networks to monitoring and decision making in the operation of nuclear power plants. Summary

Application of neural networks to monitoring and decision making in the operation of nuclear power plants is being investigated under a US Department of Energy sponsored program at the University of Tennessee. Projects include the feasibility of using neural networks for the following tasks: (1) diagnosing specific abnormal conditions or problems in nuclear power plants, (2) detection of the change of mode of operation of the plant, (3) validating signals coming from detectors, (4) review of ``noise`` data from TVA`s Sequoyah Nuclear Power Plant, and (5) examination of the NRC`s database of ``Letter Event Reports`` for correlation of sequences of events in the reported incidents. Each of these projects and its status are described briefly in this paper. This broad based program has as its objective the definition of the state-of-the-art in using neural networks to enhance the performance of commercial nuclear power plants.
Date: December 31, 1990
Creator: Uhrig, R. E.
System: The UNT Digital Library
An approach for selecting safety class items (open access)

An approach for selecting safety class items

DOE Order 6430.1A, General Design Criteria, requires that DOE facilities be evaluated with regard to ``safety class items.`` Safety class items are defined as ``systems, components, and structures, including portions of process systems, whose failure could adversely affect the environment or safety and health of the public. Determination of safety classification is based on analysis of potential abnormal and accidental scenario consequences as presented in the Safety Analysis Report.`` Although the General Design Criteria defines safety class items, it does not provide an approach for selecting safety class items. The purpose of this report is to present the approach which was developed for selecting safety class items in a specific nonreactor nuclear facility project at the Savannah River Site (SRS).
Date: December 31, 1990
Creator: Low, J. M.
System: The UNT Digital Library
Ash accumulation effects using bench marked 0-D model (open access)

Ash accumulation effects using bench marked 0-D model

Ash accumulation is a key issue relative to our ability to achieve D-{sup 3}He ARIES III burn conditions. 1-1/2-d transport simulations using the BALDUR code have been used to examine the correlation between the global ash particle confinement time and the edge exhaust (or recycling) efficiency. This provides a way to benchmark the widely used 0-D model. The burn conditions for an ARIES-III plasma with various ash edge recycling coefficients are examined.
Date: December 31, 1990
Creator: Hu, S. C.; Guo, J. P. & Miley, G. H.
System: The UNT Digital Library
Assessment of RAMONA-3B methodology with FRIGG dynamic tests (open access)

Assessment of RAMONA-3B methodology with FRIGG dynamic tests

The computer codes used at Brookhaven National Laboratory to compute BWR safety parameters are the Engineering Plant Analyzer (EPA) and RAMONA-3B/MOD1. Both codes have the same methodology for modeling thermal hydraulic phenomena: drift-flux formulation, two-phase multipliers for the wall friction and form losses calculations, and the momentum integral approach for spatial integration of the loop momentum equations. Both codes use explicit integration methods for solving ordinary differential equations. It is concluded that both the codes are capable of modelling the instability problems for a BWR. The accuracy of thermohydraulics codes predictions was assessed by modelling oscillatory FRIGG tests. Nodalizations studies showed that 24 axial nodes were sufficient for a converged solution, 12 axial nodes produced an error of 4.4% in the gain of the power to flow transfer function. The code predicted consistently the effects of power and inlet subcooling on gain and system resonance frequency. The comparisons showed that the code predicted the peak gains with a mean difference from experiments of 7% {plus_minus} 30% for all the tests modeled. The uncertainty in the experimental data is {minus}11% to +12%. The mean difference in the predicted frequency at the peak gain is {minus}6% {plus_minus} 14%.
Date: December 31, 1990
Creator: Rohatgi, U. S.; Neymotin, L. Y. & Wulff, W.
System: The UNT Digital Library
Automated spike preparation system for Isotope Dilution Mass Spectrometry (IDMS) (open access)

Automated spike preparation system for Isotope Dilution Mass Spectrometry (IDMS)

Isotope Dilution Mass Spectrometry (IDMS) is a method frequently employed to measure dissolved, irradiated nuclear materials. A known quantity of a unique isotope of the element to be measured (referred to as the ``spike``) is added to the solution containing the analyte. The resulting solution is chemically purified then analyzed by mass spectrometry. By measuring the magnitude of the response for each isotope and the response for the ``unique spike`` then relating this to the known quantity of the ``spike``, the quantity of the nuclear material can be determined. An automated spike preparation system was developed at the Savannah River Site (SRS) to dispense spikes for use in IDMS analytical methods. Prior to this development, technicians weighed each individual spike manually to achieve the accuracy required. This procedure was time-consuming and subjected the master stock solution to evaporation. The new system employs a high precision SMI Model 300 Unipump dispenser interfaced with an electronic balance and a portable Epson HX-20 notebook computer to automate spike preparation.
Date: December 31, 1990
Creator: Maxwell, S. L., III & Clark, J. P.
System: The UNT Digital Library
Automated system for validating balance performance (open access)

Automated system for validating balance performance

Manual tank calibrations often have variabilities of both a random and systematic nature that often affect the quality of the data collected for determining accurate calibration equations. When performing the calibration run, data omissions and transcriptions often occur (forgetting to tare weigh the prover vessel or miswriting a displayed value). A computer can be used to minimize these errors associated with the logging of data. This paper describes a IBM compatible, portable computer based system, developed at the Savannah River Site (SRS), that was used to calibrate three tanks in the second quarter 1990. It received data directly from instrumentation such as Ruska differential pressure sensors and electronic balances, while prompting the technicians to perform the various steps in the calibration procedure. This automated system greatly improved the quality of data for calculating the calibration equation for each of these tanks over previous calibration runs.
Date: December 31, 1990
Creator: Gibbs, P. W. & Clark, J. P.
System: The UNT Digital Library
Automated tank calibration system using a portable computer (open access)

Automated tank calibration system using a portable computer

Manual tank calibrations often have variabilities of both a random and systematic nature that often affect the quality of the data collected for determining accurate calibration equations. When performing the calibration run, data omissions and transcriptions often occur (forgetting to tare weigh the prover vessel or miswriting a displayed value). A computer can be used to minimize these errors associated with the logging of data. This paper describes a IBM compatible, portable computer based system, developed at the Savannah River Site (SRS), that was used to calibrate three tanks in the second quarter 1990. It received data directly from instrumentation such as Ruska differential pressure sensors and electronic balances, while prompting the technicians to perform the various steps in the calibration procedure. This automated system greatly improved the quality of data for calculating the calibration equation for each of these tanks over previous calibration runs.
Date: December 31, 1990
Creator: Holt, S. H.; Harvel, C. D. & Clark, J. P.
System: The UNT Digital Library
Automated tank calibrations using installed measurement equipment (open access)

Automated tank calibrations using installed measurement equipment

A menu driven automatic tank calibration program was established at one of the new facilities at the Savannah River Site (SRS). Approximately 100 tanks ranging in size from 10 to 21,000 liters were calibrated. Tank level instrumentation included a precision level system using Ruska instruments multiplexed to several tanks via a Scanivalve system, standard process level differential pressure transmitters, capacitance probes, and temperature devices. Most of the tank instruments were connected to data collection computers. Scales were temporarily connected to the data collection computers to input solution weights and to record the scale calibration data. Flat panel displays were used for information feedback to operators including when to transmit weighs, data transmitted, tank instrument readings, and other procedural steps. The automated data collection permitted signal averaging and consistency checks to improve the quality of the data and minimize repeat calibrations. This paper will provide a description of the calibration system, equipment used, unique features of the system, and an assessment of the quality of the data collected.
Date: December 31, 1990
Creator: Crawford, J. M.
System: The UNT Digital Library
Axial power monitoring uncertainty in the Savannah River Reactors (open access)

Axial power monitoring uncertainty in the Savannah River Reactors

The results of this analysis quantified the uncertainty associated with monitoring the Axial Power Shape (APS) in the Savannah River Reactors. Thermocouples at each assembly flow exit map the radial power distribution and are the primary means of monitoring power in these reactors. The remaining uncertainty in power monitoring is associated with the relative axial power distribution. The APS is monitored by seven sensors that respond to power on each of nine vertical Axial Power Monitor (APM) rods. Computation of the APS uncertainty, for the reactor power limits analysis, started with a large database of APM rod measurements spanning several years of reactor operation. A computer algorithm was used to randomly select a sample of APSs which were input to a code. This code modeled the thermal-hydraulic performance of a single fuel assembly during a design basis Loss-of Coolant Accident. The assembly power limit at Onset of Significant Voiding was computed for each APS. The output was a distribution of expected assembly power limits that was adjusted to account for the biases caused by instrumentation error and by measuring 7 points rather than a continuous APS. Statistical analysis of the final assembly power limit distribution showed that reducing reactor power …
Date: December 31, 1990
Creator: Losey, D. C. & Revolinski, S. M.
System: The UNT Digital Library
Behavior of liquid metal droplets in an aspirating nozzle. Revision (open access)

Behavior of liquid metal droplets in an aspirating nozzle. Revision

Measurements of particle size, velocity, and relative mass flux were made on spray field produced by aspirating liquid tin into 350{degrees}C argon flowing through a venturi nozzle via a small orifice in the throat of the nozzle. Details of the aspiration and droplet formation process were observed through windows in the nozzle. The spatial distribution of droplet size, velocity, and relative number density were measured at a location 10 mm from the nozzle exit. Due to the presence of separated flow in the nozzle, changes in nozzle inlet pressure did not significantly effect resulting droplet size and velocity. This suggests that good aerodynamic nozzle design is required if spray characteristics are to be controlled by nozzle flow. 5 refs.
Date: December 31, 1990
Creator: Swank, W. D.; Fincke, J. R. & Mason, T. A.
System: The UNT Digital Library
Boundary integral methods for unsaturated flow (open access)

Boundary integral methods for unsaturated flow

Many large simulations may be required to assess the performance of Yucca Mountain as a possible site for the nations first high level nuclear waste repository. A boundary integral equation method (BIEM) is described for numerical analysis of quasilinear steady unsaturated flow in homogeneous material. The applicability of the exponential model for the dependence of hydraulic conductivity on pressure head is discussed briefly. This constitutive assumption is at the heart of the quasilinear transformation. Materials which display a wide distribution in pore-size are described reasonably well by the exponential. For materials with a narrow range in pore-size, the exponential is suitable over more limited ranges in pressure head. The numerical implementation of the BIEM is used to investigate the infiltration from a strip source to a water table. The net infiltration of moisture into a finite-depth layer is well-described by results for a semi-infinite layer if {alpha}D > 4, where {alpha} is the sorptive number and D is the depth to the water table. the distribution of moisture exhibits a similar dependence on {alpha}D. 11 refs., 4 figs.,
Date: December 31, 1990
Creator: Martinez, M.J. & McTigue, D.F.
System: The UNT Digital Library
Closure of a mixed waste landfill: Lessons learned (open access)

Closure of a mixed waste landfill: Lessons learned

Much experience has been gained during the closure of the Mixed Waste Management Facility (MWMF) at the Savannah River Site (SRS) and many lessons were learned. This knowledge was applied to other closures at SRS yielding decreased costs, schedule enhancement, and increased overall project efficiency. The next major area of experience to be gained at SRS in the field of waste site closures will be in the upkeep, maintenance, and monitoring of clay caps. Further test programs will be required to address these requirements.
Date: December 31, 1990
Creator: Phifer, M. A.
System: The UNT Digital Library
Control of high-level radioactive waste-glass melters. Part 4, Preliminary analysis of DWPF process laboratory capabilities (open access)

Control of high-level radioactive waste-glass melters. Part 4, Preliminary analysis of DWPF process laboratory capabilities

The Defense Waste Processing Facility (DWPF) will immobilize Savannah River Site High Level Waste as a durable borosilicate glass for permanent disposal in a repository. The DWPF will be controlled based on glass composition. The following discussion is a preliminary analysis of the capability of the laboratory methods that can be used to control the glass composition, and the relationships between glass durability and glass properties important to glass melting. The glass durability and processing properties will be controlled by controlling the chemical composition of the glass. The glass composition will be controlled by control of the melter feed transferred from the Slurry Mix Evaporator (SME) to the Melter Feed Tank (MFT). During cold runs, tests will be conducted to demonstrate the chemical equivalence of glass sampled from the pour stream and glass removed from cooled canisters. In similar tests, the compositions of glass produced from slurries sampled from the SME and MFT will be compared to final product glass to determine the statistical relationships between melter feed and glass product. The total error is the combination of those associated with homogeneity in the SME or MFT, sampling, preparation of samples for analysis, instrument calibration, analysis, and the composition/property model. …
Date: December 31, 1990
Creator: Bickford, D. F. & Coleman, C. J.
System: The UNT Digital Library
Control of high level radioactive waste-glass melters. Part 6, Noble metal catalyzed formic acid decomposition, and formic acid/denitration (open access)

Control of high level radioactive waste-glass melters. Part 6, Noble metal catalyzed formic acid decomposition, and formic acid/denitration

A necessary step in Defense Waste Processing Facility (DWPF) melter feed preparation for the immobilization of High Level Radioactive Waste (HLW) is reduction of Hg(II) to Hg(0), permitting steam stripping of the Hg. Denitrition and associated NOx evolution is a secondary effect of the use of formic acid as the mercury-reducing agent. Under certain conditions the presence of transition or noble metals can result in significant formic acid decomposition, with associated CO{sub 2} and H{sub 2} evolution. These processes can result in varying redox properties of melter feed, and varying sequential gaseous evolution of oxidants and hydrogen. Electrochemical methods for monitoring the competing processes are discussed. Laboratory scale techniques have been developed for simulating the large-scale reactions, investigating the relative effectiveness of the catalysts, and the effectiveness of catalytic poisons. The reversible nitrite poisoning of formic acid catalysts is discussed.
Date: December 31, 1990
Creator: Bickford, D. F.; Coleman, C. J.; Hsu, C. L. W. & Eibling, R. E.
System: The UNT Digital Library