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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,171 records · Page 65
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Business in orbit - The commercial use of space

Current and proposed business opportunities in space are discussed. The advantages offered by the zero gravity environment of space are examined. The roles of the Space Shuttle and the Space Station in space commercialization are described. International development and use of the Space Station is proposed. It is observed that the communications satellite industry is a successful space venture, and opportunities for materials processing and pharmaceuticals production in space are considered. The relationship between NASA's Office of Commercial Programs, which assists businesses in space commercialization, and industry is studied. The impact of space commercialization on the national economy and international trade is analyzed.

Gillam, I. T., IV↗
NASA NTRS1987

Acquisition-Management Program

NASA Acquisition Management Subsystem (AMS) program integrated NASA-wide standard automated-procurement-system program developed in 1985. Designed to provide each NASA installation with procurement data-base concept with on-line terminals for managing, tracking, reporting, and controlling contractual actions and associated procurement data. Subsystem provides control, status, and reporting for various procurement areas. Purpose of standardization is to decrease costs of procurement and operation of automatic data processing; increases procurement productivity; furnishes accurate, on-line management information and improves customer support. Written in the ADABAS NATURAL.

Avery, Don E.↗
NASA NTRS1986

Toxicological safeguards in the manned Mars missions

Safeguards against toxic chemical exposures during manned Mars missions (MMMs) will be important for the maintenance of crew health and the accomplishment of mission objectives. Potential sources include offgassing, thermodegradation or combustion of materials, metabolic products of crew members, and escape of chemical from containment. Spacecraft maximum allowable concentration (SMAC) limits will have to be established for potential contaminants during the MMMs. The following factors will be used in establishing these limits: duration of mission, simultaneous exposure to other contaminants, deconditioning of crew members after long periods of reduced gravity, and simultaneous exposure to ionizing radiation. Atmospheric contaminant levels in all compartments of the transit spacecraft and Manned Mars Station (MMS) will be monitored at frequent intervals with a real time analyzer. This analyzer will be highly automated, requiring minimal crew time and expertise. The atmospheric analyzer will find other usages during the MMMs such as analyzing Martian atmospheres and soils, exhaled breath and body fluids of crew members, and reaction products in chemical processing facilities.

Coleman, Martin E.↗
NASA NTRS1987

Phase partitioning, crystal growth, electrodeposition and cosmic ray experiments in microgravity

Five experiments are contained in one Get Away Special Canister (5 cu ft). The first utilizes microgravity to separate biological cells and to study the mechanism of phase partitioning in 12 separate cuvettes. Two experiments are designed to grow organic crystals by physical vapor transport. One experiment consists of eight electroplating cells with various chemicals to produce surfaces electroplated in microgravity. Some of the surfaces have micron sized particles of hard materials co-deposited during electrodeposition. The fifth experiment intercepts cosmic ray particles and records their paths on photographic emulsions. The first four experiments are controlled by an on-board C-MOS controller. The fifth experiment is totally passive. These are the first in Space. Their purpose is to create new commercial products with microgravity processing.

Wessling, Francis C.↗
NASA NTRS1985

Four applications of a software data collection and analysis methodology

The evaluation of software technologies suffers because of the lack of quantitative assessment of their effect on software development and modification. A seven-step data collection and analysis methodology couples software technology evaluation with software measurement. Four in-depth applications of the methodology are presented. The four studies represent each of the general categories of analyses on the software product and development process: blocked subject-project studies, replicated project studies, multi-project variation studies, and single project strategies. The four applications are in the areas of, respectively, software testing, cleanroom software development, characteristic software metric sets, and software error analysis.

Basili, Victor R.↗
NASA NTRS1986

Quantitative photoabsorption and fluorescence study of H2O and D2O at 50-190 nm

The photoabsorption cross sections and the fluorescence quantum yields of H2O and D2O were measured in the 50-190 nm region using synchrotron radiation as a light source. The oscillator strengths for the Rydberg states of H2O and D2O were determined from the absorption cross sections measured. The processes for the production of fluorescence from the excited species H(asterisk) (n greater than 2), D(asterisk) (n greater than 2), OH(asterisk) (A) and OD(asterisk) (A) are discussed. The upper limit for the dissociation energy of D(D-OD) was determined, from the threshold of the OD(A-X) fluorescence, to be 5.14 + or - 0.01 eV. The upper limit for the cross section of visible fluorescence from the excited H2O(+) ions was determined to be 2 x 10 to the -19th sq cm. A comparison between the photoexcitation spectra of H2O and D2O is made.

Lee, L. C.↗
NASA NTRS1987

Controlled Ecological Life Support System: Regenerative Life Support Systems in Space

A wide range of topics related to the extended support of humans in space are covered. Overviews of research conducted in Japan, Europe, and the U.S. are presented. The methods and technologies required to recycle materials, especially respiratory gases, within a closed system are examined. Also presented are issues related to plant and algal productivity, efficiency, and processing methods. Computer simulation of closed systems, discussions of radiation effects on systems stability, and modeling of a computer bioregenerative system are also covered.

Macelroy, Robert D.↗
NASA NTRS1988

Progress in InP solar cell research

Progress, in the past year, in InP solar cell research is reviewed. Small area cells with AMO, total area efficiencies of 18.8 percent were produced by OMCVD and Ion Implantation. Larger area cells (2 and 4 sq cm) were processed on a production basis. One thousand of the 2 sq cm cells will be used to supply power to a small piggyback lunar orbiter scheduled for launch in February 1990. Laboratory tests of ITO/InP cells, under 10 MeV proton irradiation, indicate radiation resistance comparable to InP n/p homojunction cells. Computer modeling studies indicate that, for identical geometries and dopant concentrations, InP solar cells are significantly more radiation resistant than GaAs under 1 MeV electron irradiation. Additional computer modeling calculations were used to produce rectangular and circular InP concentrator cell designs for both the low concentration SLATS and higher concentration Cassegrainian Concentrators.

Weinberg, Irving↗
NASA NTRS1988

High-ozone events in Atlanta, Georgia, in 1983 and 1984

Measurements of ozone levels and meterological parameters were analyzed to determine the relative importance of transport-related processes and photochemical production in causing high-ozone events in and around the Atlanta metropolitan area. Back-trajectories calculated by the Branching Air Trajectory Model indicate that the air associated with high-ozone events had often traveled a significant distance within the previous 3 days: for days with ozone levels above 100 ppbv, half of the calculated trajectories showed that the air had traveled over 600 km, with half of those coming from the northwest quadrant. Six-hour vector-averaged winds were used to find that the concentrations of ozone in the air leaving the metropolitan area averaged 20-40 ppbv more than that entering the area.

Lindsay, Ronald W.↗
NASA NTRS1988

Beyond the Station

The NASA Pathfinder program for sending humans and robots to explore the solar system is discussed. The various technologies which are to be developed to support the program are described, emphasizing technology for an in-situ resource-processing plant for production of oxygen on the moon and space nuclear power for propulsion to the outer planets. The use of Pathfinder to validate advanced propulsion concepts and the use of aerobraking to land on Mars are discussed. Communications between Mars and earth are addressed. Mission scenarios currently under consideration for Pathfinder are examined.

Mankins, John C.↗
NASA NTRS1989

Observations of, and sources of the spatial and temporal variability of ozone in the middle atmosphere on climatological time scales (OZMAP) and equatorial dynamics: Seasonal variations of ozone trends

The long term trends (least square linear regression with time) of ozone content at seven European, seven North American, three Japanese and two tropical stations during 21 years (1964 to 1984) are analyzed. In all regions negative trends are observed during the 1970s, but are partly compensated by limited periods of positive trends during the late 1960s and late 1970s. Solely the North American ozone data show negative trends in all 10 year periods. When the long term ozone trends are evaluated for each month of the year separately, a seasonal variation is revealed, which in Europe and North America has largest negative trends in late winter and spring. While in Europe the negative trends in winter/spring are partly compensated by positive trends in summer, in North America the summer values reach only zero, retaining the significant negative trend in annual mean values. In contrast to the antarctic ozone hole, the spring reduction of ozone in Europe and in North America is associated with stratospheric temperatures increasing in the analyzed period and therefore is consistent with the major natural ozone production and loss processes.

Entzian, G.↗
NASA NTRS1988

Progress in InP solar cell research

Progress, in the past year, in InP solar cell research is reviewed. Small area cells with AMO, total area efficiencies of 18.8 percent were produced by OMCVD and Ion Implantation. Larger area cells (2 and 4 sq cm) were processed on a production basis. One thousand of the 2 sq cm cells will be used to supply power to a small piggyback lunar orbiter scheduled for launch in February 1990. Laboratory tests of ITO/InP cells, under 10 MeV proton irradiation, indicate radiation resistance comparable to InP n/P homojunction cells. Computer modeling studies indicate that, for identical geometries and dopant concentrations, InP solar cells are significantly more radiation resistant than GaAs under 1 MeV electron irradiation. Additional computer modeling calculations were used to produce rectangular and circular InP concentrator cell designs for both the low concentration SLATS and higher concentration Cassegrainian Concentrators.

Weinberg, I.↗
NASA NTRS1989

Wet spinning of solid polyamic acid fibers

The invention is a process for the production of solid aromatic polyamic acid and polyimide fibers from a wet gel or coagulation bath wet gel using N,N-dimethylacetamide (DMAc) solution of the polyamic acid derived from aromatic dianhydrides such as 3,3',4,4'-benzo phenone tetracarboxylic dianhydride (BTDA) and aromatic diamines such as 4,4'oxydianiline (4,4'-ODA). By utilizing the interrelationship between coagulation medium and concentration, resin inherent viscosity, resin percent solids, filament diameter, and fiber void content, it is possible to make improved polyamic acid fibers. Solid polyimide fibers, obtained by the thermal cyclization of the polyamic acid precursor, have increased tensile properties compared to fibers containing macropores from the same resin system.

Dorogy, William E., Jr.↗
NASA NTRS1989

Science plan for the Alaska SAR facility program. Phase 1: Data from the first European sensing satellite, ERS-1

Science objectives, opportunities and requirements are discussed for the utilization of data from the Synthetic Aperture Radar (SAR) on the European First Remote Sensing Satellite, to be flown by the European Space Agency in the early 1990s. The principal applications of the imaging data are in studies of geophysical processes taking place within the direct-reception area of the Alaska SAR Facility in Fairbanks, Alaska, essentially the area within 2000 km of the receiver. The primary research that will be supported by these data include studies of the oceanography and sea ice phenomena of Alaskan and adjacent polar waters and the geology, glaciology, hydrology, and ecology of the region. These studies focus on the area within the reception mask of ASF, and numerous connections are made to global processes and thus to the observation and understanding of global change. Processes within the station reception area both affect and are affected by global phenomena, in some cases quite critically. Requirements for data processing and archiving systems, prelaunch research, and image processing for geophysical product generation are discussed.

Carsey, Frank D.↗
NASA NTRS1989

Space Station Freedom operations planning

The Space Station Freedom program is developing an operations planning structure which assigns responsibility for planning activities to three tiers of management. The strategic level develops the policy, goals and requirements for the program over a five-year horizon. Planning at the tactical level emphasizes program integration and planning for a two-year horizon. The tactical planning process, architecture, and products have been documented and discussed with the international partners. Tactical planning includes the assignment of user and system hardware as well as significant operational events to a time increment (the period of time from the arrival of one Shuttle to the manned base to the arrival of the next). Execution-level planning emphasizes implementation, and each organization produces detailed plans, by increment, that are specific to its function.

Accola, Anne L.↗
NASA NTRS1990

Chemical heterogeneity and imperfect mixing in the solar nebula

The 'standard' accretion-disk model of the solar nebula is examined together with its basic equations, which are solved for the steady-state case. It is shown that, for this model of the solar nebula, the efficiency of mixing the products of thermochemical processing from small to large disk radii depends not on the magnitude of the eddy diffusivity but only on the ratio k between the eddy diffusivity and the eddy viscosity. In most cases, this ratio k is probably of order of unity or less, implying that most of the solar nebula was not contaminated by the consequences of thermochemical equilibria that were established at 'small' disk radii. It is noted that, while this condition is almost certainly satisfied if the physical process responsible for viscosity is thermal convection or waves, it has uncertain validity during the early phases of disk evolution where accretion-induced shear instabilities may dominate.

Stevenson, David J.↗
NASA NTRS1990

Hot hydrogen and oxygen atoms in the upper atmospheres of Venus and Mars

Optical observations of hot atoms in the atmospheres of Venus and Mars are briefly reviewed. A summary of hot hydrogen and oxygen production and loss processes is given. Results of some recent model calculations as well as a number of new results of the hot hydrogen and oxygen populations are presented and their implication in terms of solar wind interaction processes is discussed.

Nagy, Andrew F.↗
NASA NTRS1990

NASA Space Engineering Research Center for utilization of local planetary resources

The University of Arizona and NASA have joined to form the UA/NASA Space Engineering Research Center. The purpose of the Center is to discover, characterize, extract, process, and fabricate useful products from the extraterrestrial resources available in the inner solar system (the moon, Mars, and nearby asteroids). Individual progress reports covering the center's research projects are presented and emphasis is placed on the following topics: propellant production, oxygen production, ilmenite, lunar resources, asteroid resources, Mars resources, space-based materials processing, extraterrestrial construction materials processing, resource discovery and characterization, mission planning, and resource utilization.

Ramohalli, Kumar↗