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Institutional research and development, FY 1987 (open access)

Institutional research and development, FY 1987

The Institutional Research and Development program at Lawrence Livermore National Laboratory fosters exploratory work to advance science and technology, disciplinary research to develop innovative solutions to problems in various scientific fields, and long-term interdisciplinary research in support of defense and energy missions. This annual report describes research funded under this program for FY87. (DWL)
Date: January 1, 1987
Creator: Struble, G. L.; Lawler, G. M.; Crawford, R. B.; Kirvel, R. D.; Peck, T. M.; Prono, J. K. et al.
System: The UNT Digital Library
Development and process evaluation of improved Fischer-Tropsch slurry catalysts (open access)

Development and process evaluation of improved Fischer-Tropsch slurry catalysts

The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.
Date: January 1, 1987
Creator: Withers, H.P. (Air Products and Chemicals, Inc., Allentown, PA (United States)); Bukur, D.B. & Rosynek, M.P. (Texas A and M Univ., College Station, TX (United States))
System: The UNT Digital Library
The performance of the NEC SX-2 and Cray X-MP supercomputers (open access)

The performance of the NEC SX-2 and Cray X-MP supercomputers

Since our first article on the Japanese supercomputers appeared in the December 1985 issue of Computer, we have conducted additional benchmarks of the new NEC SX-2 vector processor. We present these new results for the SX-2 and updated timings of the X-MP/48. 5 refs., 1 fig., 6 tabs.
Date: January 1, 1987
Creator: Lubeck, O. M.; Moore, J. W. & Mendez, R.
System: The UNT Digital Library
Determination of optimum electrolyte composition for molten carbonate fuel cells (open access)

Determination of optimum electrolyte composition for molten carbonate fuel cells

The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have state-of-the-art cell voltage and lifetime.
Date: January 1, 1987
Creator: Yuh, C. Y. & Pigeaud, A.
System: The UNT Digital Library
Low cost hydrogen/novel membranes technology for hydrogen separation from synthesis gas, Phase 1. [Palladium-silver/poly(etherimide), polysulfone/poly(dimethylsiloxane)/poly(ether-esteramide)composite membranes] (open access)

Low cost hydrogen/novel membranes technology for hydrogen separation from synthesis gas, Phase 1. [Palladium-silver/poly(etherimide), polysulfone/poly(dimethylsiloxane)/poly(ether-esteramide)composite membranes]

During this quarter, work continued on the development of high-flux palladium-silver membranes for the separation of hydrogen from carbon dioxide. Palladium-silver/poly(etherimide) composite membranes were prepared by a vacuum sputtering technique. The influence of different poly(etherimide) support membranes on the performance of palladium-silver membranes was investigated. All membranes tested showed a hydrogen/carbon dioxide selectivity lower than that of the uncoated poly(etherimide)/poly(dimethylsiloxane) membranes. This is probably due to damage of the skin layer of the asymmetric poly(etherimide) support membranes during the palladium-silver electron bombardment. Polysulfone/poly(dimethylsiloxane)/poly(ether-ester-amide) composite membranes were also prepared. Membrane samples consistently showed a carbon dioxide/hydrogen selectivity of 9 to 10 and a normalized carbon dioxide flux of 2 to 4 {times} 10{sup {minus}4} cm{sup 3} (STP)/cm{sup 2}{center dot}sec{center dot}cmHg. These are extremely good values, superior to any commercially available membranes for this separation. 2 figs., 4 tabs.
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Determination of optimum electrolyte composition for molten carbonate fuel cells (open access)

Determination of optimum electrolyte composition for molten carbonate fuel cells

The goal of this program is the development of a molten carbonate fuel cell (MCFC) anode which is more tolerant of sulfur contaminants in the fuel than the current state-of-the-art nickel-based anode structures. This program addresses two different but related aspects of the sulfur contamination problem. The primary aspect is concerned with the development of a sulfur tolerant electrocatalyst for the fuel oxidation reaction. A secondary issue is the development of a sulfur tolerant water-gas-shift reaction catalyst and an investigation of potential steam reforming catalysts which also have some sulfur tolerant capabilities. These two aspects are being addressed as two separate tasks.
Date: January 1, 1987
Creator: Yuh, C. Y. & Pigeaud, A.
System: The UNT Digital Library
Kinetics of coal pyrolysis and devolatilization (open access)

Kinetics of coal pyrolysis and devolatilization

The objective of these experimental and modeling studies is to develop an improved understanding of the kinetics of coal devolatilization which is relevant to suspension firing of powdered coal. These fundamental kinetic studies address several topics related to pulverized coal combustion and include both homogeneous and heterogeneous reactions. The principal topics include: (1) the pyrolysis and devolatilization of coal; and (2) the formation of char. Research activities include small-scale experimentation, interpretation of experimental results in terms of mechanistic understanding and the development and validation of kinetic models of fundamental processes. This report consists of two contributions. The first is from MIT entitled Intra-Particle Heat Transfer Effects in Coal Pyrolysis''. While this modeling study bears some similarity to the Ohio State work, it is proposed as the starting point for a more complete model which will include other boundary conditions as well as mass transfer effects. The second contribution is a report from UTRC entitled Effect of Heat Transfer on Tar and Light Gases From Coal Pyrolysis''. This work documents some of the changes in the chemical composition of the products of pyrolysis when the mode or rate of heat transfer is varied. 28 refs., 17 figs., 3 tabs.
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Development of a current collection loss management system for SDI homopolar power supplies (open access)

Development of a current collection loss management system for SDI homopolar power supplies

High speed, high power density current collection systems have been identified as an enabling technology required to construct homopolar power supplies to meet SDI missions. This work is part of a three-year effort directed towards the analysis, experimental verification, and prototype construction of a current collection system designed to operated continuously at 2 kA/cm{sup 2}, at a rubbing speed of 200 m/s, and with acceptable losses in a space environment. To data, no system has achieved these conditions simultaneously. This is the annual report covering the first year period of performance on DOE contract DE-AC03-86SF16518. Major areas covered include design and construction of a cryogenically-cooled brush test rig, design of a high speed brush test rig, loss analysis of the current collection system, and an application study which defines the air core homopolar construction necessary to achieve the goal of 80--90 kW/kg generator power density. 15 figs.
Date: January 1, 1987
Creator: Hannan, W.F. III.
System: The UNT Digital Library
(Support of the board on ocean science and policy) (open access)

(Support of the board on ocean science and policy)

The National Academy of Sciences, through the Ocean Studies Board of the Commission on Physical Sciences, Mathematics and Resources, proposes to provide guidance on major ocean sciences and policy issues to the National Oceanic and Atmospheric Administration, the National Science Foundation, the Department of the Navy, the US Geological Survey, the Minerals Management Service of the Department of the Interior, the US Coast Guard, the Department of State, the Department of Energy, The Environmental Protection Agency, and the National Aeronautics and Space Administration. The work plan for this activity is presented in the program plan section of this proposal. Work plans for subsequent years will be submitted prior to the commencement of work. Financial support is requested for continued support of the Ocean Studies Board activities from 1 June 1987 through 31 May 1989. Funds in the amount of $513,400 are requested for the period 1 June 1987 through 31 May 1988, as indicated in the attached estimate of costs.
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Kinetics of coal pyrolysis and devolatilization (open access)

Kinetics of coal pyrolysis and devolatilization

Research continued an coal pyrolysis and devolatilization. An experimentally based, conceptual model of the devolatilization of a HV bituminous coal is outlined in this repair. This model contends that the relative dominance of a process type-chemical kinetic, heat transport, mass transport -- varies with the extent of reaction for a given set of heating conditions and coal type and with experimental and with experimental conditions for a given coal types and extent of reaction. The relevant reference'' conditions of interest for direct utilization are rapid transient heating of small (< 100 micron) particles to temperatures of 1000{degrees}C or greater. The model postulatew that the overall rates of coal devolatilization should vary with coal type insofar as the characteristics of the parent coal determine the potential tar yield and the chemical characteristics of the initial tars. Experimental evidence indicates chemical characteristics and yields of primary'' tars vary significant with coal type. Consequently, the conceptual model would indicate a shift from transport to chemical dominance of rate processes with variation in coal types. Using the conceptual model, UTRC has been able to correlate initial mass loss with a heat transfer index for a wide range of conditions for high tar yielding coals. …
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Kinetics of coal pyrolysis and devolatilization (open access)

Kinetics of coal pyrolysis and devolatilization

An experimentally based, conceptual model of the devolatilization of a HV bituminous coal is outlined in this report. This model contends that the relative dominance of a process type-chemical kinetic, heat transport, mass transport -- varies with the extent of reaction for a given set of heating conditions and coal type and with experimental conditions for a given coal type and extent of reaction. The rate of devolatilization mass loss process is dominated initially by heat transfer processes, then coupled mass transfer and chemical kinetics, and finally by chemical processes alone. However, the chemical composition of the initial tars are determined primarily by the chemical characteristics of the parent coal. Chemically controlled gas phase reactions of the initial tars and coupled mass transfer and chemically controlled reactions of heavy tars determine the bulk of the light gas yields. For a HV bituminous coal this conceptual model serves to quantify the Two-Component Hypothesis'' of volatiles evolution. The model postulates that the overall rates of coal devolatilization should vary with coal type insofar as the characteristics of the parent coal determine the potential tar yield and the chemical characteristics of the initial tars. Experimental evidence indicates chemical characteristics and yields of primary'' …
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Determination of optimum electrolyte composition for molten carbonate fuel cells (open access)

Determination of optimum electrolyte composition for molten carbonate fuel cells

The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.
Date: January 1, 1987
Creator: Yuh, C. Y. & Pigeaud, A.
System: The UNT Digital Library
Computer codes used in particle accelerator design: First edition (open access)

Computer codes used in particle accelerator design: First edition

This paper contains a listing of more than 150 programs that have been used in the design and analysis of accelerators. Given on each citation are person to contact, classification of the computer code, publications describing the code, computer and language runned on, and a short description of the code. Codes are indexed by subject, person to contact, and code acronym. (LEW)
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Weldon Spring, Missouri: Annual environmental monitoring report, calendar year 1987 (open access)

Weldon Spring, Missouri: Annual environmental monitoring report, calendar year 1987

Radiological monitoring at the WSS during 1987 measured uranium, Radium-226, and Thorium-230 concentrations in surface water, groundwater, and sediment; radon gas concentrations in air; all long-lived natural series isotopes in air particulates; and external gamma radiation exposure rates. Potential radiation doses to the public were calculated based on assumed exposure periods and the above measurements. Radon concentrations, external gamma exposure rates, and radionuclide concentrations in groundwater and surface water at the site were generally equivalent to previous years' levels. The maximum calculated annual radiation dose to a hypothetically exposed individual at the WSRP and WSCP area was 1 mrem, or 1 percent of the DOE radiation protection standard of 100 mrem. The maximum calculated annual radiation dose to a hypothetically exposed individual at the WSQ was 14 mrem, or about 14 percent of the standard. Thus the WSS currently complies with DOE Off-site Dose Standards. Chemical contamination monitoring at the WSS during 1987 measured nitroaromatics, total organic carbon and the inorganic anions chloride, nitrate, fluoride and sulfate in surface water, groundwater and sediment. 22 refs., 26 figs., 21 tabs.
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Sodium Waste Technology : a Summary Report (open access)

Sodium Waste Technology : a Summary Report

The Sodium Waste Technology (SWT) Program was established to resolve long-standing issues regarding disposal of sodium-bearing waste and equipment. Comprehensive SWT research programs investigated a variety of approaches for either removing sodium from sodium-bearing items, or disposal of items containing sodium residuals. The most successful of these programs was the design, test, and the production operation of the Sodium Process Demonstration Facility at ANL-W. The technology used was a series of melt-drain-evaporate operations to remove nonradioactive sodium from sodium-bearing items and then converting the sodium to storable compounds.
Date: January 1987
Creator: Abrams, C. S. & Witbeck, L. C.
System: The UNT Digital Library
Measurement of Stibine and Arsine Generation from the Exide 3100-Ah Lead-Acid Module (open access)

Measurement of Stibine and Arsine Generation from the Exide 3100-Ah Lead-Acid Module

Stibine and arsine evolution from lead-acid cells in a 36-kWh Exide load-leveling module was measured as this module approached 1900 cycles of operation. A specially prepared gas-collection apparatus enabled us to determine the maximum and average rates for evolution of both toxic hydrides. Hydride generation began once the cell voltage exceeded 2.4 V. The maximum rate for arsine occurred just above 2.5 V and consistently preceded the peak rate for stibine for each sampled cell. When adjusted for size effects, the degree of stibine and arsine evolution was greater than found in a continuous overcharge study conducted by Exide. The average rates of hydride generation were found to be 175 microgm/min for stibine and 12.6 microgm/min for arsine. The former rate proved to be the critical value in determining safe ventilation requirements for cell off-gases. The minimum airflow requirement was calculated to be 340 L/min per cell. Projections for a hypothetical 1-MWh Exide battery without an abatement system indicated that the normal ventilation capacity in the Battery Energy Storage Test facility provides nearly five times the airflow needed for safe hydride removal.
Date: January 1987
Creator: Marr, J. J. & Smaga, J. A.
System: The UNT Digital Library
A Theory of Program Correctness, and Algorithms for Proofs (open access)

A Theory of Program Correctness, and Algorithms for Proofs

A model of program correctness is given where a problem domain is defined by its language, variable names, and an abstract machine defining the semantics of the language. The set of all computations in this domain is shown to be a semigroup. A corresponding statement is true of a more general programming language. A program P in the general language is an element of the semigroup. If P performs computations in some domain, a connection can be established between P and the semigroup of computations in that domain. Methods already used in proofs about hardware are shown to be useful in proofs about this software model. The paradigm is capable of reasoning about multiprocessor hardware and of ''proving'' theorems about execution times, that is, ''performance.''
Date: January 1987
Creator: Gabriel, John R.; Chapman, Richard O. & Kljaich, J. L.
System: The UNT Digital Library
²³⁵U(n,f), ²³⁸U(n, gamma), ²³⁸U(n,f), ²³⁹Pu(n,f) Reaction Rate Measurement Calibrations at ZPPR (open access)

²³⁵U(n,f), ²³⁸U(n, gamma), ²³⁸U(n,f), ²³⁹Pu(n,f) Reaction Rate Measurement Calibrations at ZPPR

New reference deposits for uranium-235, plutonium-239 and uranium-238 have been established with mass uncertainties of <0.2%. These new deposits replace the older reference deposits which were used during the last 17 years and improve the uncertainty of reaction rate measurements due to reference mass uncertainties by about a factor of 6. Measurements of the fission fragment absorption in 2 pi and low-geometry count rates. Two measurements of the uranium-238 capture rate in depleted uranium samples based upon the thermal cross sections of uranium-238(n, gamma), uranium-235(n,f) and plutonium-239(n,f) and based upon the americium-243 calibration technique confirm the ZPPR measurement technique within the quoted uncertainty of +/-0.5%
Date: January 1987
Creator: Poenitz, W. P.; Maddison, D. W.; Gasidlo, J. M.; Carpenter, S.G. & Armani, R. J.
System: The UNT Digital Library
Weathering effects on the structure and reactivity of US coals: Final report, July 15, 1984-July 14, 1987. [Many data] (open access)

Weathering effects on the structure and reactivity of US coals: Final report, July 15, 1984-July 14, 1987. [Many data]

This report covers the work performed from July 1984 to July 1987 under the project entitled ''Weathering Effects on Structure and Reactivity of US Coals'' (grant number FG22-84PC70798). The main objectives of the study were to investigate the structural changes in coal during the weathering process as well as to develop a simple, reliable weathering index, which can monitor indirectly the weathering-induced changes in physical and chemical properties. Although there have been numerous publications on structure and reactivity of coal, most data reported in the literature thus far have been obtained on coal samples of uncertain weathering status and therefore need to be interpreted with great caution. Weathering has a profound effect on many important coal properties such as heating value, caking characteristics, acidity, flotability and reactivity in liquefaction, combustion and gasification processes. The objective of developing a weathering index is to predict these coal property changes due to weathering without resorting to real-time measurements or pilot plant runs. This report is comprised of four main chapters: I. Structural Changes due to Weathering; II. Material Balance in Weathering Process; III. Development of a Reliable Weathering Index; and IV. Proposed Weathering Mechanisms. A battery of sophisticated analytical tools and techniques was …
Date: January 1, 1987
Creator: Meuzelaar, H.L.C.; Hill, G.R.; Yun, Yongseung; Jakab, E.; Windig, W.; Urban, D. et al.
System: The UNT Digital Library
Emerging supercomputer architectures (open access)

Emerging supercomputer architectures

This paper will examine the current and near future trends for commercially available high-performance computers with architectures that differ from the mainstream ''supercomputer'' systems in use for the last few years. These emerging supercomputer architectures are just beginning to have an impact on the field of high performance computing. 7 refs., 1 tab.
Date: January 1, 1987
Creator: Messina, P. C.
System: The UNT Digital Library
Color magnetism in pion photoproduction and radiative delta decay (open access)

Color magnetism in pion photoproduction and radiative delta decay

We use the extant multipole data base to extract the ..gamma..N-..delta.. transition amplitudes, using the phenomenology of the effective Lagrangian approach. We find evidence for hadronic color magnetism in the radiative delta decay amplitudes. 24 refs., 2 tabs.
Date: January 1, 1987
Creator: Mukhopadhyay, N. C. & Davidson, R.
System: The UNT Digital Library
Hot Dry Rock Geothermal Energy Development Program: Annual report, fiscal year 1985 (open access)

Hot Dry Rock Geothermal Energy Development Program: Annual report, fiscal year 1985

The primary objective for the Hot Dry Rock Program at the Los Alamos National Laboratory during fiscal year 1985 was to complete the Phase 2 reservoir connection and to begin flow testing the resulting reservoir. The connection was achieved through redrilling one well and additional fracturing operations, and progress was made toward developing a detailed understanding of the fractured region through a variety of reservoir interrogation methods. Other accomplishments during the fiscal year included improvement of the high-temperature, inflatable, open-hole packer used to isolate sections of the uncased wellbore in collaboration with the Baker Corporation and the design and fabrication of a high-temperature borehole acoustic televiewer in a cooperative program with a research institute in West Germany. Progress was also made in techniques for the collection and analysis of microseismic data. Reservoir-engineering activities and geochemical studies, as well as the more routine support activities, continued in FY85. 18 refs., 15 figs.
Date: January 1, 1987
Creator: Brown, D. W.; Franke, P. R.; Smith, M. C. & Wilson, M. G.
System: The UNT Digital Library
Geological evolution and analysis of confirmed or suspected gas hydrate localities: Volume 10, Basin analysis, formation and stability of gas hydrates of the Aleutian Trench and the Bering Sea (open access)

Geological evolution and analysis of confirmed or suspected gas hydrate localities: Volume 10, Basin analysis, formation and stability of gas hydrates of the Aleutian Trench and the Bering Sea

Four major areas with inferred gas hydrates are the subject of this study. Two of these areas, the Navarin and the Norton Basins, are located within the Bering Sea shelf, whereas the remaining areas of the Atka Basin in the central Aleutian Trench system and the eastern Aleutian Trench represent a huge region of the Aleutian Trench-Arc system. All four areas are geologically diverse and complex. Particularly the structural features of the accretionary wedge north of the Aleutian Trench still remain the subjects of scientific debates. Prior to this study, suggested presence of the gas hydrates in the four areas was based on seismic evidence, i.e., presence of bottom simulating reflectors (BSRs). Although the disclosure of the BSRs is often difficult, particularly under the structural conditions of the Navarin and Norton basins, it can be concluded that the identified BSRs are mostly represented by relatively weak and discontinuous reflectors. Under thermal and pressure conditions favorable for gas hydrate formation, the relative scarcity of the BSRs can be attributed to insufficient gas supply to the potential gas hydrate zone. Hydrocarbon gas in sediment may have biogenic, thermogenic or mixed origin. In the four studied areas, basin analysis revealed limited biogenic hydrocarbon …
Date: January 1, 1987
Creator: Krason, J. & Ciesnik, M.
System: The UNT Digital Library
Particulate emissions from residential wood combustion: Final report: Norteast regional Biomass Program (open access)

Particulate emissions from residential wood combustion: Final report: Norteast regional Biomass Program

The objective of this study was to provide a resource document for the Northeastern states when pursuing the analysis of localized problems resulting from residential wood combustion. Specific tasks performed include assigning emission rates for total suspended particulates (TSP) and benzo(a)pyrene (BaP) from wood burning stoves, estimating the impact on ambient air quality from residential wood combustion and elucidating the policy options available to Northeastern states in their effort to limit any detrimental effects resulting from residential wood combustion. Ancillary tasks included providing a comprehensive review on the relevant health effects, indoor air pollution and toxic air pollutant studies. 77 refs., 11 figs., 25 tabs.
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library