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)

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 first six months of 1992 on research activities associated with these two systems. (GHH)

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 initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

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 the alkali metal, and low electrical resistance, other high temperature components of the cell face equally demanding requirements. The beta{double prime} alumina solid electrolyte (BASE), the seal between the BASE ceramic and its metallic transition to the hot alkali metal (liquid or vapor) source, and metallic components of the device are exposed to hot liquid alkali metal. Modification of AMTEC components may also be useful in optimizing the device for particular operating conditions. In particular, a potassium AMTEC may be expected to operate more efficiently at lower temperatures.

The purpose of the following computer study is to determine the set of necessary conditions under which the addition of photo-voltaic (PV) cells to electric vehicles provides a net utility or economic benefit. Economic benefits are given the primary focus and are evaluated in terms of a payback period.

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 development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.

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 report covers the fifth quarter of work. The major accomplishments were: (1) Completion of coal liquefaction autoclave reactor runs and related analysis with Illinois no. 6 coal at 400{degrees}C with and without surfactant and/or catalyst at pressures of 1700 psig; (2) A literature search into the effect that lignin has in the coprocessing of coal; and (3) Presentation of a report summarizing the first year of work on this task at the Annual Liquefaction Contractors Review Conference. Results from this quarter show that lignosulfonate surfactant continues to increase overall MAF conversion of Illinois no. 6 coal at temperatures up to 400{degrees}C and produces an improvement in light boiling fraction distillate over the base case of no surfactant addition.

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 report covers the second quarter of work. The major accomplishments were (1) completion of coal liquefaction autoclave reactor runs with Illinois No. 6 coal at processing temperatures of 300, 325, and 350{degrees}C, and pressures of 1800 psig, (2) analysis of the filter cake and the filtrate obtained from the treated slurry in each run, and (3) correlation of the coal conversions and the liquid yield quality to the surfactant concentration. An increase in coal conversions and upgrading of the liquid product quality due to surfactant addition was observed for all runs.

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.

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)

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 first six months of 1992 on research activities associated with these two systems. (GHH)

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 cells. Quantitative estimates confirm that the efficiency is insensitive to either the work required to pressurize the sodium liquid or the details of the state changes associated with cooling the low pressure sodium gas to the heat rejection temperature. 10 refs.

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 distribution automation. In this application the network is required to reach all parts of the power system, and the fiber cable itself becomes a significant fraction of the cost of communications. However, since many applications can be supported at once, the cost per function can be reasonable.

A phase 11 study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of, quantifying the enhancement in liquid yields and product quality. This report covers the third quarter of work. The major accomplishments were (1) completion of coal liquefaction autoclave reactor runs and related analysis with Illinois {number_sign}6 coal at a processing temperature of 375{degree}C, and pressures of 1800 and 1500 psig, (2) completion and analysis of two autoclave reactor runs to observe the synergistic effect of the surfactant and an iron catalyst, and (3) setting up a subcontract with HRI Inc. to test the surfactant enhanced liquefaction process in a continuous flow reactor.

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 cell (RTC) have demonstrated sustained conversion efficiencies as high as 10.2% early in cell life and 9.7% after maturity. Extensive thermal and electrochemical analysis of the cell during several experiments demonstrated that the efficiency could be improved in two ways. First, the electrode performance could be improved. The electrode for these tests operated at about one third the power density of state of the art electrodes. The low power density was caused by a combination of high series resistance and high mass flow resistance. Reducing these resistances could improve the efficiency to greater than 10%. Second, the cell thermal performance could be improved. Efficiencies greater than 14% could be realized through reducing the radiative thermal loss. Further improvements to the efficiency range predicted by systems studies …

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 photocurrent measurement (CPM), junction capacitance, drive-level capacitance profiling (DLCP), optical transmission, light and dark photoconductivity, and small-angle X-ray scattering (SAXS). Conventional ECR-deposited a-Si:H was compared to a new form, a-Si:(Xe, H), in which xenon gas was added to the ECR plasma. a-Si:(Xe,H) possessed low, stable dark conductivities and high photosensitivites. Light-soaking revealed photodegradation rates about 35% lower than those of comparable radio frequency (rf)-deposited material. ECR-deposited p-type a SiC:H and intrinsic a-Si:H films underwent evaluation as components of p-i-n solar cells with standard rf films for the remaining layers.

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 development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.

The present work effort relates to an investigation of surfactant-assisted coal liquefaction with the objective of quantifying the enhancement in overall coal conversions and the product quality. Based on the results of a Phase 1 preliminary study on the effect of several surfactants on coal liquefaction, sodium lignosulfonate was chosen as the surfactant for a detailed parametric study to be conducted at JPL using a batch autoclave reactor. These tests primarily related to thermal liquefaction of coal. The results of JPL autoclave test runs showed an increase in overall conversions from 5 to 15% due to surfactant addition over the base case of coal alone. A continuous-flow bench scale coal liquefaction process run was conducted over a 5-day period at Hydrocarbon Research Incorporated (HRI). This test showed that the surfactant is suitable for an industrial continuous recycle process, and does not interfere with the supported catalyst. After the bench scale test, a series of autoclave runs were conducted with coprocessing the surfactant and the Ni-Mo catalyst. These experiments showed that high conversions and product quality can be maintained at milder processing conditions. Based on results of the autoclave test runs, the overall product values were obtained for two stage reactors …

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, including thin, mature molybdenum electrodes which exhibit transport dominated by free molecular flow of sodium gas at low frequencies or dc conditions. Activated surface transport will almost always exist in parallel with free molecular flow transport, and the process of alkali atom adsorption/desorption from the electrode surface will invariably be part of the transport process, and possibly a dominant part in some cases. Little can be learned about the detailed mass transport process from the ac impedance or current voltage curves of an electrode at one set of operating parameters, because the transport process includes a number of important physical parameters that are not all uniquely determined by one experiment. The temperature dependence of diffusion coefficient of the alkali metal through the electrode in several cases provides an activation energy and …

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, including thin, mature molybdenum electrodes which exhibit transport dominated by free molecular flow of sodium gas at low frequencies or dc conditions. Activated surface transport will almost always exist in parallel with free molecular flow transport, and the process of alkali atom adsorption/desorption from the electrode surface will invariably be part of the transport process, and possibly a dominant part in some cases. Little can be learned about the detailed mass transport process from the ac impedance or current voltage curves of an electrode at one set of operating parameters, because the transport process includes a number of important physical parameters that are not all uniquely determined by one experiment. The temperature dependence of diffusion coefficient of the alkali metal through the electrode in several cases provides an activation energy and …

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 report covers the second quarter of work. The major accomplishments were (1) completion of coal liquefaction autoclave reactor runs with Illinois No. 6 coal at processing temperatures of 300, 325, and 350[degrees]C, and pressures of 1800 psig, (2) analysis of the filter cake and the filtrate obtained from the treated slurry in each run, and (3) correlation of the coal conversions and the liquid yield quality to the surfactant concentration. An increase in coal conversions and upgrading of the liquid product quality due to surfactant addition was observed for all runs.

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 the degree of importance NEP might have in advancing NASA space science goals; and to disseminate the results in a format useful to both NEP users and technology developers. This is a mission performance study and precludes investigations of multitudes of new mission operation and systems design issues attendant in a NEP flight.

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 initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

The Pasadena Workshop on System Software and Tools for High Performance Computing Environments was held at the Jet Propulsion Laboratory from April 14 through April 16, 1992. The workshop was sponsored by a number of Federal agencies committed to the advancement of high performance computing (HPC) both as a means to advance their respective missions and as a national resource to enhance American productivity and competitiveness. Over a hundred experts in related fields from industry, academia, and government were invited to participate in this effort to assess the current status of software technology in support of HPC systems. The overall objectives of the workshop were to understand the requirements and current limitations of HPC software technology and to contribute to a basis for establishing new directions in research and development for software technology in HPC environments. This report includes reports written by the participants of the workshop`s seven working groups. Materials presented at the workshop are reproduced in appendices. Additional chapters summarize the findings and analyze their implications for future directions in HPC software technology development.