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A 2D electrostatic PIC code for the Mark III Hypercube

Description: 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 partic… more
Date: December 31, 1990
Creator: Ferraro, R. D.; Liewer, P. C. & Decyk, V. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Activated transport in AMTEC electrodes

Description: Transport of alkali metal atoms through porous cathodes of alkali metal thermal-to-electric converter (AMTEC) cells is responsible for significant, reducible losses in the electrical performance of these cells. Experimental evidence for activated transport of metal atoms at grain surfaces and boundaries within some AMTEC electrodes has been derived from temperature dependent studies as well as from analysis of the detailed frequency dependence of ac impedance results for other electrodes, inclu… more
Date: July 1, 1992
Creator: Williams, R. M.; Jeffries-Nakamura, B.; Ryan, M. A.; Underwood, M. L.; O`Connor, D. & Kikkert, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Activated transport in AMTEC electrodes

Description: Transport of alkali metal atoms through porous cathodes of alkali metal thermal-to-electric converter (AMTEC) cells is responsible for significant, reducible losses in the electrical performance of these cells. Experimental evidence for activated transport of metal atoms at grain surfaces and boundaries within some AMTEC electrodes has been derived from temperature dependent studies as well as from analysis of the detailed frequency dependence of ac impedance results for other electrodes, inclu… more
Date: January 1, 1992
Creator: Williams, R.M.; Jeffries-Nakamura, B.; Ryan, M.A.; Underwood, M.L.; O'Connor, D. & Kikkert, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

Description: Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of… more
Date: January 1, 1991
Creator: Williams, R.M.; Jeffries-Nakamura, B.; Underwood, M.L.; Ryan, M.A.; O'Connor, D. & Kikkert, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

Description: Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of… more
Date: December 31, 1991
Creator: Williams, R. M.; Jeffries-Nakamura, B.; Underwood, M. L.; Ryan, M. A.; O`Connor, D. & Kikkert, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design considerations for a fiber optic communications network for power systems

Description: The design of a fiber optic communication network for monitoring and control in power systems is discussed. It is shown that by appropriate choice of protocols, a fault-tolerant system can be built that operates in any arbitrary configuration. Since the network is based on fiber optics, it can be made fast enough for substation monitoring and control. In this application, a relatively small number of cables is required to implement a high reliability system. The network can also be used for dis… more
Date: August 1, 1993
Creator: Kirkham, H.; Johnston, A. R. & Allen, G. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of alternative oxygen production source using a zirconia solid electrolyte membrane

Description: The objective of this multiyear effort was the development, fabrication and testing of a zirconia oxygen production module capable of delivering approximately 100 liters/minute (LPM) of oxygen. The work discussed in this report consists of development and improvement of the zirconia cell along with manufacture of cell components, preliminary design of the final plant, additional economic analysis and industrial participation. (VC)
Date: August 1, 1990
Creator: Suitor, J. W.; Clark, D. J. & Losey, R. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of alternative oxygen production source using a zirconia solid electrolyte membrane. Final report

Description: The objective of this multiyear effort was the development, fabrication and testing of a zirconia oxygen production module capable of delivering approximately 100 liters/minute (LPM) of oxygen. The work discussed in this report consists of development and improvement of the zirconia cell along with manufacture of cell components, preliminary design of the final plant, additional economic analysis and industrial participation. (VC)
Date: August 1, 1990
Creator: Suitor, J. W.; Clark, D. J. & Losey, R. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Direct Conversion Technology

Description: The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. Initially, two systems were selected for exploratory research and advanced development. These are Alkali Metal Thermal-to-Electric Converter (AMTEC) and Two-Phase Liquid Metal MD Generator (LMMHD). This report describes progress that has been made during the … more
Date: July 1, 1992
Creator: Back, L.H.; Fabris, G. & Ryan, M.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Direct conversion technology

Description: The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was… more
Date: January 7, 1992
Creator: Massier, P.F.; Back, L.H.; Ryan, M.A. & Fabris, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Direct conversion technology. Annual summary report CY 1991, January 1, 1991--December 31, 1991

Description: The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was… more
Date: January 7, 1992
Creator: Massier, P. F.; Back, L. H.; Ryan, M. A. & Fabris, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Direct Conversion Technology. Progress report, January 1, 1992--June 30, 1992

Description: The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. Initially, two systems were selected for exploratory research and advanced development. These are Alkali Metal Thermal-to-Electric Converter (AMTEC) and Two-Phase Liquid Metal MD Generator (LMMHD). This report describes progress that has been made during the … more
Date: July 1, 1992
Creator: Back, L. H.; Fabris, G. & Ryan, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dynamic load balancing in a concurrent plasma PIC code on the JPL/Caltech Mark III hypercube

Description: Dynamic load balancing has been implemented in a concurrent one-dimensional electromagnetic plasma particle-in-cell (PIC) simulation code using a method which adds very little overhead to the parallel code. In PIC codes, the orbits of many interacting plasma electrons and ions are followed as an initial value problem as the particles move in electromagnetic fields calculated self-consistently from the particle motions. The code was implemented using the GCPIC algorithm in which the particles ar… more
Date: December 31, 1990
Creator: Liewer, P. C.; Leaver, E. W.; Decyk, V. K. & Dawson, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Efficiency of an AMTEC recirculating test cell, experiments and projections

Description: The alkali metal thermal to electric converter (AMTEC) is an electrochemical device for the direct conversion of heat to electrical energy with efficiencies potentially near Carnot. The future usefulness of AMTEC for space power conversion depends on the efficiency of the devices. Systems studies have projected from 15% to 35% thermal to electric conversion efficiencies, and one experiment has demonstrated 19% efficiency for a short period of time. Recent experiments in a recirculating test cel… more
Date: May 1, 1992
Creator: Underwood, M. L.; O`Connor, D.; Williams, R. M.; Jeffries-Nakamura, B. & Ryan, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electrical characterization of electrophoretically coated aluminum samples for photovoltaic concentrator application

Description: The practicality of using a thin-film styrene/acrylate copolymer electrophoretic coating to isolate concentrator cells electrically from their surroundings in a photovoltaic concentrator module is assessed. Only the electrical isolation problem was investigated. The approach was to subject various types of EP-coated aluminum specimens to electrical stress testing and to aging tests while monitoring coating electrical resistivity properties. It was determined that, in general, longer processing … more
Date: October 1, 1992
Creator: Sugimura, R. S.; Mon, G. R. & Ross, R. G. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron cyclotron resonance deposition of amorphous silicon alloy films and devices

Description: This report describes work to develop a state-of-the-art electron cyclotron resonance (ECR) plasma-enhanced chemical vapor deposition (PECVD) system. The objective was to understand the deposition processes of amorphous silicon (a-Si:H) and related alloys, with a best-effort improvement of optoelectronic material properties and best-effort stabilization of solar cell performance. ECR growth parameters were systematically and extensively investigated; materials characterization included constant… more
Date: October 1, 1992
Creator: Shing, Y. H. (Jet Propulsion Lab., Pasadena, CA (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron cyclotron resonance deposition of amorphous silicon alloy films and devices. Final subcontract report, 1 April 1991--31 March 1992

Description: This report describes work to develop a state-of-the-art electron cyclotron resonance (ECR) plasma-enhanced chemical vapor deposition (PECVD) system. The objective was to understand the deposition processes of amorphous silicon (a-Si:H) and related alloys, with a best-effort improvement of optoelectronic material properties and best-effort stabilization of solar cell performance. ECR growth parameters were systematically and extensively investigated; materials characterization included constant… more
Date: October 1, 1992
Creator: Shing, Y. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New vision solar system mission study. Final report

Description: The vision for the future of the planetary exploration program includes the capability to deliver {open_quotes}constellations{close_quotes} or {open_quotes}fleets{close_quotes} of microspacecraft to a planetary destination. These fleets will act in a coordinated manner to gather science data from a variety of locations on or around the target body, thus providing detailed, global coverage without requiring development of a single large, complex and costly spacecraft. Such constellations of spac… more
Date: March 1, 1996
Creator: Mondt, J. F. & Zubrin, R. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear electric propulsion for future NASA space science missions

Description: This study has been made to assess the needs, potential benefits and the applicability of early (circa year 2000) Nuclear Electric Propulsion (NEP) technology in conducting NASA science missions. The study goals are: to obtain the performance characteristics of near term NEP technologies; to measure the performance potential of NEP for important OSSA missions; to compare NEP performance with that of conventional chemical propulsion; to identify key NEP system requirements; to clarify and depict… more
Date: July 20, 1993
Creator: Yen, Chen-wan L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reversible thermodynamic cycle for AMTEC power conversion

Description: The thermodynamic cycle appropriate to an AMTEC (alkali metal thermal-to-electric converter) cell is discussed for both liquid- and vapor-fed modes of operation, under the assumption that all processes can be performed reversibly. In the liquid-fed mode, the reversible efficiency is greater than 89.6% of Carnot efficiency for heat input and rejection temperatures (900--1300 K and 400--800 K, respectively) typical of practical devices. Vapor-fed cells can approach the efficiency of liquid-fed ce… more
Date: July 1, 1992
Creator: Vining, C. B.; Williams, R. M.; Underwood, M. L.; Ryan, M. A. & Suitor, J. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SP-100 operational life model. Fiscal Year 1990 annual report

Description: This report covers the initial year`s effort in the development of an Operational Life Model (OLM) for the SP-100 Space Reactor Power System. The initial step undertaken in developing the OLM was to review all available documentation from GE on their plans for the OLM and on the degradation and failure mechanisms envisioned for the SP-100. In addition, the DEGRA code developed at JPL, which modelled the degradation of the General Purpose Heat Source based Radioisotope Thermoelectric Generator (… more
Date: December 14, 1990
Creator: Ewell, R. & Awaya, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spray combustion modeling. Final report

Description: Concern over the future availability of high quality liquid fuels or use in furnaces and boilers prompted the U. S. Department of Energy (DOE) to consider alternate fuels as replacements for the high grade liquid fuels used in the 1970`s and 1980`s. Alternate fuels were defined to be combinations of a large percentage of viscous, low volatility fuels resulting from the low end of distillation mixed with a small percentage of relatively low viscosity, high volatility fuels yielded by the high en… more
Date: March 1, 1997
Creator: Bellan, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The study of redox-active inorganic substituents of cellulase enzymes. Quarterly report, 25 August--25 November 1993

Description: Cellulase (CBHI) was modified by bis (2,2- bipyridine) ruthenium (II) and the modified enzyme was assayed for cellulase activity using p- nitrophenyl beta-D-cellobioside as substrate. Absorption spectroscopy of native and modified CBHI was also conducted.
Date: December 31, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surfactant studies for bench-scale operation

Description: A phase II study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This publication covers the first quarter of work. The major accomplishments were: (1) the refurbishment of the high-pressure, high-temperature reactor autoclave, (2) the completion of four coal liquefaction runs with Pittsburgh [number sign]8 coal, two each with and without sodium lignosulfonate surfactant, and (3) the… more
Date: December 30, 1992
Creator: Hickey, G.S. & Sharma, P.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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