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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

Magnetic beneficiation of lunar soils

We will present a review of recent laboratory results obtained in dry magnetic separation of one gram samples of the minus 1 mm size fraction of five lunar soils of widely differing maturities. Two highland soils were investigated as potential sources of low iron content feed stocks for space manufacture of metals, including aluminum, silicon, and calcium. Pure anorthite was separated from the diamagnetic fraction of immature highland regolith. Three high titanium mare soils were investigated as potential sources of ilmenite for production of hydrogen and for recovery of He-3. Ilmenite and pyroxene were separated from the paramagnetic fractions of the mare basalts. Agglutinates and other fused soil components containing metallic iron were separated from the strongly magnetic fractions of all soils. We will present conceptual magnetic separation flow sheets developed from the laboratory data and designed for production of anorthite from highland soils and for production of ilmenite from mare soils. Using these flow sheets, we will discuss problems and opportunities associated with the magnetic separation of lunar soils. Separation of high-grade anorthite or other diamagnetic components at moderately high recovery can be achieved in processing immature highland soils. Further, while magnet weight is always an issue in magnetic separation technology, recent developments in both low temperature and high temperature superconductivity present unusual opportunities for magnet design specific to the lunar environment.

Mckay, D. S↗
NASA NTRS1992

Propellant production and useful materials: Hardware data from components and the systems

Research activities at the University of Arizona/NASA Space Engineering Research Center are described; the primary emphasis is on hardware development and operation. The research activities are all aimed toward introducing significant cost reductions through the utilization of resources locally available at extraterrestrial sites. The four logical aspects include lunar, Martian, support, and common technologies. These are described in turn. The hardware realizations are based upon sound scientific principles which are used to screen a host of interesting and novel concepts. Small scale feasibility studies are used as the screen to allow only the most promising concepts to proceed. Specific examples include: kg/day-class oxygen plant that uses CO2 as the feed stock, spent stream utilization to produce methane and 'higher' compounds (using hydrogen from a water electrolysis plant), separation of CO from the CO2, reduction of any iron bearing silicate (lunar soils), production of structural components, smart sensors and autonomous controls, and quantitative computer simulation of extraterrestrial plants. The most important feature of all this research continues to be the training of high-quality students for our future in space.

Ramohalli, Kumar↗
NASA NTRS1992

Nested-hierarchical scene models and image segmentation

An improved model of scenes for image analysis purposes, a nested-hierarchical approach which explicitly acknowledges multiple scales of objects or categories of objects, is presented. A multiple-pass, region-based segmentation algorithm improves the segmentation of images from scenes better modeled as a nested hierarchy. A multiple-pass approach allows slow and careful growth of regions while interregion distances are below a global threshold. Past the global threshold, a minimum region size parameter forces development of regions in areas of high local variance. Maximum and viable region size parameters limit the development of undesirably large regions. Application of the segmentation algorithm for forest stand delineation in TM imagery yields regions corresponding to identifiable features in the landscape. The use of a local variance, adaptive-window texture channel in conjunction with spectral bands improves the ability to define regions corresponding to sparsely stocked forest stands which have high internal variance.

Woodcock, C.↗
NASA NTRS1992

Helicopter noise prediction - The current status and future direction

The paper takes stock of the progress, assesses the current prediction capabilities, and forecasts the direction of future helicopter noise prediction research. The acoustic analogy approach, specifically, theories based on the Ffowcs Williams-Hawkings equations, are the most widely used for deterministic noise sources. Thickness and loading noise can be routinely predicted given good plane motion and blade loading inputs. Blade-vortex interaction noise can also be predicted well with measured input data, but prediction of airloads with the high spatial and temporal resolution required for BVI is still difficult. Current semiempirical broadband noise predictions are useful and reasonably accurate. New prediction methods based on a Kirchhoff formula and direct computation appear to be very promising, but are currently very demanding computationally.

Brentner, Kenneth S.↗
NASA NTRS1993

Remote sensing of submerged vegetation canopies for biomass estimation

The visible bands of the Landsat Thematic Mapper (TM) sensor were used in an empirical assessment of seagrass biomass on shallow banks near Lee Stocking Island in the Bahamas. The TM bands were transformed to minimize the depth-dependent variance in the bottom reflectance signal. Regression analyses were performed between the transformed bands and field measurements of seagrass standing crop (above-ground biomass). Regression equations using spectral data accounted for up to 80 per cent of the variability in seagrass biomass. The unexplained variance was ascribed to variations in bottom sediment color.

Armstrong, Roy A.↗
NASA NTRS1992

Learning about primates' learning, language, and cognition

Results are presented of many years of research on the methods of teaching primates the language and cognitive skills which were long considered to be unteachable to particular species of primates. It was found that chimpanzee subjects could not only learn a number of 'stock sentences' but to use them in variations and several combinations for the purpose of solving various problems. Apes placed in different rooms could be taught to communicate via computer, and collaborate with each other on doing specific tasks. Contrary to expectations, young rhesus monkeys proved to be able to learn as much as the chimpanzee species.

Rumbaugh, Duane M.↗
NASA NTRS1992

Iodine addition using triiodide solutions

The study develops: a triiodide solution for use in preparing ground service equipment (GSE) water for Shuttle support, an iodine dissolution method that is reliable and requires minimal time and effort to prepare, and an iodine dissolution agent with a minimal concentration of sodium salt. Sodium iodide and hydriodic acid were both found to dissolve iodine to attain the desired GSE iodine concentrations of 7.5 +/- 2.5 mg/L and 25 +/- 5 mg/L. The 1.75:1 and 2:1 sodium iodide solutions produced higher iodine recoveries than the 1.2:1 hydriodic acid solution. A two-hour preparation time is required for the three sodium iodide solutions. The 1.2:1 hydriodic acid solution can be prepared in less than 5 min. Two sodium iodide stock solutions (2.5:1 and 2:1) were found to dissolve iodine without undergoing precipitation.

Rutz, Jeffrey A.↗
NASA NTRS1992

Utilization of on-site resources for Regenerative Life Support Systems at a lunar outpost

Regenerative life support systems (RLSS) will be required to regenerate air, water, and wastes, and to produce food for human consumption during long-duration stays on the moon. It may be possible to supplement some of the materials needed for RLSS from resources on the moon. Natural materials at the lunar surface may be used for a variety of lunar RLSS needs, including (i) soils or solid-support substrates for plant growth, (ii) sources for extraction of essential, plant-growth nutrients, (iii) substrates for microbial populations in the degradation of wastes, (iv) sources of O2 and H, which may be used to manufacture water, (v) feed stock materials for the synthesis of useful minerals (e.g., molecular sieves), and (vi) shielding materials surrounding the outpost structure to protect humans, plants, and microorganisms from harmful radiation.

Ming, D. W.↗
NASA NTRS1993

Compact color schlieren optical system

A compact optical system for use with rainbow schlieren deflectometry is described. Both halves of the optical system consist of well-corrected telescopes whose refractive elements are all from manufacturer's stock catalogs, with the reflective primary being a spherical surface. As a result, the system is relatively easy to construct and meets the requirement of long focal length for quantitative rainbow schlieren measurements.

Buchele, Donald R.↗
NASA NTRS1992

Toxic substances registry system: Index of material safety data sheets

The Oct. 1992 Revision of the KSC Toxic Substances Registry System (TSRS) Index of Material Safety Data Sheets (MSDS's) is presented. The listed MSDS's reflect product inventories and associated MSDS's which were submitted to the Toxic Substance Registry Data Base maintained by the Base Operations Contractors of the Biomedical Operations and Research Office of KSC. The purpose of the index is to provide a means of accessing information on the hazards associated with the toxic and otherwise hazardous chemicals stored and used at KSC. Indices are provided for manufacturers, trademarks, and stock numbers.

Source record↗
NASA NTRS1993

Toxic substances registry system: Index of material safety data sheets

The Jan. 1993 Revision of the KSC Toxic Substances Registry System (TSRS) Index of Material Safety Data Sheets (MSDS's) is presented. The listed MSDS's reflect product inventories and associated MSDS's which were submitted to the Toxic Substance Registry Data Base maintained by the Base Operations Contractors of the Biomedical Operations and Research Office of KSC. The purpose of the index is to provide a means of accessing information on the hazards associated with the toxic and otherwise hazardous chemicals stored and used at KSC. Indices are provided for manufacturers, trademarks, and stock numbers.

Source record↗
NASA NTRS1922

The disposal of military aircraft

The end of the war saw every belligerent with vast stocks of aircraft and aircraft supplies in all stages of usefulness, much of the material being absolutely new. The question of the best method of getting rid of this accumulation is one which has been agitating those responsible for its disposal for more than three years now, but no wholly satisfactory solution has yet been reached.

Warner, Edward P↗
NASA NTRS1957

Rupture Strength of Several Nickel-base Alloys in Sheet Form

The 100-hour rupture strengths of Inconel X, Inconel 700, Incoloy 901, Refractaloy 26, and R-235 at 1200 and 1350 F. in both the annealed and heat-treated conditions were determined. Inconel 700 had the highest rupture strength at both temperatures; Incoloy 901 was second strongest at 1200 F, and R-235 second strongest at 1350 F. With the exception of Incoloy 901, ductility was low. Photomicrographs show that fractures are through the grain boundaries. Results are compared with published data for other sheet alloys and bar stock.

ALLOYS, HEAT-RESISTING↗
NASA NTRS1920

The Strength of One-Piece Solid, Build-Up and Laminated Wood Airplane Wing Beams

The purpose of this report is to summarize the results of all wood airplane wing beams tested to date in the Bureau of Standards Laboratory in order that the various kinds of wood and methods of construction may be compared. All beams tested were of an I section and the majority were somewhat similar in size and cross section to the front wing beam of the Curtiss JN-4 machine. Construction methods may be classed as (1) solid beams cut from solid stock; (2) three-piece beams, built up of three pieces, web and flanges glued together by a tongue-and-groove joint and (3) laminated beams built up of thin laminations of wood glued together.

Nelson, John H↗
NASA NTRS1951

Influence of Chemical Composition on Rupture Properties at 1200 Degrees F. of Forged Chromium-Cobalt-Nickel-Iron Base Alloys in Solution-Treated and Aged Condition

The influence of systematic variations of chemical composition on rupture properties at 1200 degrees F. was determined for 62 modifications of a basic alloy containing 20 percent chromium, 20 percent nickel, 20 percent cobalt, 3 percent molybdenum, 2 percent tungsten, 1 percent columbium, 0.15 percent carbon, 1.7 percent manganese, 0.5 percent silicon, 0.12 percent nitrogen and the balance iron. These modifications included individual variations of each of 10 elements present and simultaneous variations of molybdenum, tungsten, and columbium. Laboratory induction furnace heats were hot-forged to round bar stock, solution-treated at 2200 degrees F., and aged at 1400 degrees F. The melting and fabrication conditions were carefully controlled in order to minimize all variable effects on properties except chemical composition. Information is presented which indicates that melting and hot-working conditions play an important role in high-temperature properties of alloys of the type investigated.

Reynolds, E E↗
NASA NTRS1957

Influence of Hot-Working Conditions on High-Temperature Properties of a Heat-Resistant Alloy

The relationships between conditions of hot-working and properties at high temperatures and the influence of the hot-working on response to heat treatment were investigated for an alloy containing nominally 20 percent molybdenum, 2 percent tungsten, and 1 percent columbium. Commercially produced bar stock was solution-treated at 2,200 degrees F. to minimize prior-history effects and then rolled at temperatures of 2,200 degrees, 2,100 degrees, 2,000 degrees, 1,800 degrees, and 1,600 degrees F. Working was carried out at constant temperature and with incremental decreases in temperature simulating a falling temperature during hot-working. In addition, a few special repeated cyclic conditions involving a small reduction at high temperature followed by a small reduction at a low temperature were used to study the possibility of inducing very low strengths by the extensive precipitation accompanying such properties. Most of the rolling was done in open passes with a few check tests being made with closed passes. Heat treatments at both 2,050 degrees and 2,200 degrees F. subsequent to working were used to study the influence on response to heat treatment.

Ewing, John F↗
NASA NTRS1953

Fuel characteristics pertinent to the design of aircraft fuel systems, Supplement I : additional information on MIL-F-7914(AER) grade JP-5 fuel and several fuel oils

Since the release of the first NACA publication on fuel characteristics pertinent to the design of aircraft fuel systems (NACA-RM-E53A21), additional information has become available on MIL-F7914(AER) grade JP-5 fuel and several of the current grades of fuel oils. In order to make this information available to fuel-system designers as quickly as possible, the present report has been prepared as a supplement to NACA-RM-E53A21. Although JP-5 fuel is of greater interest in current fuel-system problems than the fuel oils, the available data are not as extensive. It is believed, however, that the limited data on JP-5 are sufficient to indicate the variations in stocks that the designer must consider under a given fuel specification. The methods used in the preparation and extrapolation of data presented in the tables and figures of this supplement are the same as those used in NACA-RM-E53A21.

Barnett, Henry C↗
NASA NTRS1994

System Would Generate Virtual Heads-Up Display

Proposed helmet-mounted electronic display system superimposes full-color alphanumerical and/or graphical information onto observer's visual field. Displayed information projected directly onto observer's retinas, giving observer illusion of full-size computer display in foreground or background. Display stereoscopic, holographic, or in form of virtual image. Used by pilots to view navigational information while looking outside or at instruments, by security officers to view information about critical facilities while looking at visitors, or possibly even stock-exchange facilities to view desktop monitors and overhead displays simultaneously. System includes acousto-optical tunable filter (AOTF), which acts as both spectral filter and spatial light modulator.

Lambert, James L.↗