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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Technology for Transportation Safety

Boston Insulated Wire & Cable developed a new polyimide foam material, commercially known as Solimide, which resists ignition. It chars and decomposes when exposed to open flames. Used in the space shuttle, the material does not "outgas" until it begins to char making it safer than current materials with respect to toxic fumes. The polyimide can be made in two forms: a resilient foam and a rigid foam. Used in commercial transport interiors for such soft components as seat cushions to door, wall, floor, and ceiling panels. Material's flame resistance could lengthen from two minutes to five minutes, the time needed for passenger evacuation in a ground emergency. Could help reduce airline fuel consumption, since the foam is 50% lighter than current materials. Low-smoke cable assemblies used in rapid transit systems consists of an advanced wire and cable jacketing material with superior flame resistance and smoke retardation characteristics. Being supplied to mass transit systems in the U.S. and abroad.

Source record↗
NASA NTRS1995

Improved Net-Level Filling And Finishing Of Large Castings

Improved method of vacuum casting of large, generally cylindrical objects to net sizes and shapes reduces amount of direct manual labor by workers in proximity to cast material. Original application for which method devised is fabrication of solid rocket-motor segments containing solid propellant, wherein need to minimize exposure of workers to propellant material being cast. Improved method adaptable to other applications involving large castings of toxic, flammable, or otherwise hazardous materials.

Johnson, Erik P.↗
NASA NTRS2001

Identification of High Performance, Low Environmental Impact Materials and Processes Using Systematic Substitution (SyS)

Process analysis can identify opportunities for efficiency improvement including cost reduction, increased safety, improved quality, and decreased environmental impact. A thorough, systematic approach to materials and process selection is valuable in any analysis. New operations and facilities design offer the best opportunities for proactive cost reduction and environmental improvement, but existing operations and facilities can also benefit greatly. Materials and processes that have been used for many years may be sources of excessive resource use, waste generation, pollution, and cost burden that should be replaced. Operational and purchasing personnel may not recognize some materials and processes as problems. Reasons for materials or process replacement may include quality and efficiency improvements, excessive resource use and waste generation, materials and operational costs, safety (flammability or toxicity), pollution prevention, compatibility with new processes or materials, and new or anticipated regulations.

Dhooge, P. M.↗
NASA NTRS2007

International Space Station Materials: Selected Lessons Learned

The International Space Station (ISS) program is of such complexity and scale that there have been numerous issues addressed regarding safety of materials: from design to manufacturing, test, launch, assembly on-orbit, and operations. A selection of lessons learned from the ISS materials perspective will be provided. Topics of discussion are: flammability evaluation of materials with connection to on-orbit operations; toxicity findings for foams; compatibility testing for materials in fluid systems; and contamination control in precision clean systems and critical space vehicle surfaces.

Golden, Johnny L.↗
NASA NTRS1977

Toxicity of pyrolysis gases from wood

The toxicity of the pyrolysis gases from nine wood samples was investigated. The samples of hardwoods were aspen poplar, beech, yellow birch, and red oak. The samples of softwoods were western red cedar, Douglas fir, western hemlock, eastern white pine, and southern yellow pine. There was no significant difference between the wood samples under rising temperature conditions, which are intended to simulate a developing fire, or under fixed temperature conditions, which are intended to simulate a fully developed fire. This test method is used to determine whether a material is significantly more toxic than wood under the preflashover conditions of a developing fire.

Hilado, C. J.↗
NASA NTRS2003

Metal Cutting Theory and Friction Stir Welding Tool Design

Friction Stir Welding (FSW) is a relatively new industrial process that was invented at The Weld Institute (TWI, United Kingdom) and patented in 1992 under research funded by in part by the National Aeronautics and Space Administration (NASA). Often quoted advantages of the process include good strength and ductility along with minimization of residual stress and distortion. Less well advertised are the beneficial effects of this solid state welding process in the field of occupational and environmental safety. It produces superior weld products in difficult to weld materials without producing any toxic fumes or solid waste that must be controlled as hazardous waste. In fact, it reduces noise pollution in the workspace as well. In the early days of FSW, most welding was performed on modified machine tools, in particular on milling machines with modified milling cutters. In spite of the obvious milling heritage of the process, the techniques and lessons learned from almost 250 years of successful metalworking with milling machines have not been applied in the field of modern Friction Stir Welding. The goal of the current research was to study currently successful FSW tools and parameterize the process in such a way that the design of new tools for new materials could be accelerated. Along the way, several successful new tooling designs were developed for current issues at the Marshall Space Flight Center with accompanying patent disclosures

Payton, Lewis N.↗
NASA NTRS1978

Toxicity of pyrolysis products: Influence of experimental conditions - The MSTL/UT and NASA/JSC Procedures

Ten sample materials of various polymeric composition were evaluated for toxicity of pyrolysis products utilizing two significantly different experimental methods, the MSTL/UT and NASA/JSC Procedures. A comparison of the LD(50) values obtained by the two methods for these ten samples did not yield a significant correlation. However, when the samples were ranked in order of increasing toxicity by each method independently, a comparison of their rank order toxicity improved the correlation. Because of interlaboratory variations in pyrolysis/combustion test procedures, it is suggested a series of standard materials be adopted to facilitate interlaboratory comparisons of data on pyrolysis toxicity.

Lawrence, W. H.↗
NASA NTRS1969

Health hazards of ultrafine metal and metal oxide powders

Study reveals that suggested threshold limit values are from two to fifty times lower than current recommended threshold limit values. Proposed safe limits of exposure to the ultrafine dusts are based on known toxic potential of various materials as determined in particle size ranges.

Boylen, G. W., Jr.↗
NASA NTRS1974

Microbiological and experimental-histological investigations of lunar samples returned by the Lunar 16 automatic station

Lunar surface material was studied for its content of viable microorganisms (aerobic and anaerobic, fungi, and viruses); the effect of the lunar surface material on the growth of microorganisms and its interaction with somatic cells of mammals was also observed. No viable microorganisms were detected; the samples exhibited neither stimulant or inhibitory action on the growth of microorganisms, and also showed no cytopathogenic action on tissue cultures. A suspension of lunar surface material particles was not toxic when parenterally administered to certain laboratory animals. The particles were subjected to intense phagocytosis by connective tissue cells in vivo and in vitro.

Kaulen, D. R.↗
NASA NTRS1976

The sensitivity of relative toxicity rankings by the USF/NASA test method to some test variables

Pyrolysis temperature and the distance between the source and sensor of effluents are two important variables in tests for relative toxicity. Modifications of the USF/NASA toxicity screening test method to increase the upper temperature limit of pyrolysis, reduce the distance between the sample and the test animals, and increase the chamber volume available for animal occupancy, did not significantly alter rankings of relative toxicity of four representative materials. The changes rendered some differences no longer significant, but did not reverse any rankings. The materials studied were cotton, wool, aromatic polyamide, and polybenzimidazole.

Hilado, C. J.↗
NASA NTRS1976

Relative toxicity of pyrolysis products of some synthetic polymers

Nineteen samples of synthetic polymers were evaluated for relative toxicity in the course of characterizing materials intended for aircraft interior applications. The generic polymers included ABS, chlorinated PVC, polycarbonate, polyphenylene oxide, polyphenylene sulfide, polysulfone, polyaryl sulfone, polyether sulfone, polybismaleimide, and polyvinyl fluoride. Test results are presented, and compared in relative rankings with similar results on cellulosic materials and other synthetic polymers. Under these test conditions, the samples of synthetic polymers were either comparable to or significantly less toxic than the samples of commercial cellulosic materials.

Hilado, C. J.↗
NASA NTRS1981

Safety management of complex research operators

Complex research and technology operations present varied potential hazards which are addressed in a disciplined, independent safety review and approval process. Potential hazards vary from high energy fuels to hydrocarbon fuels, high pressure systems to high voltage systems, toxic chemicals to radioactive materials and high speed rotating machinery to high powered lasers. A Safety Permit System presently covers about 600 potentially hazardous operations. The Safety Management Program described is believed to be a major factor in maintaining an excellent safety record.

Brown, W. J.↗
NASA NTRS1981

Safety management of complex research operations

Complex research and technology operations present many varied potential hazards which must be addressed in a disciplined independent safety review and approval process. The research and technology effort at the Lewis Research Center is divided into programmatic areas of aeronautics, space and energy. Potential hazards vary from high energy fuels to hydrocarbon fuels, high pressure systems to high voltage systems, toxic chemicals to radioactive materials and high speed rotating machinery to high powered lasers. A Safety Permit System presently covers about 600 potentially hazardous operations. The Safety Management Program described in this paper is believed to be a major factor in maintaining an excellent safety record at the Lewis Research Center.

Brown, W. J.↗
NASA NTRS1985

Beyond the biosphere

The near-earth-space, planetary and interplanetary environments are described with emphasis on their biomedical significance. The characteristics of the microgravity field, low gravity and radiation conditions in earth orbit are described, noting the necessity of avoiding materials which can outgas toxic substances during long-term mission. Details of the atmospheres, global meteorology, and terrains of Venus, Mars, Jupiter, the Jovian satellites, and Saturn are reviewed. Finally, a brief discussion is provided of the life-support systems which will be required on interstellar voyages.

Nicogossian, A. E.↗
NASA NTRS1989

Enclosed Cutting-And-Polishing Apparatus

Proposed apparatus cuts and polishes specimens while preventing contamination of outside environment or of subsequent specimens processed in it. Designed for use in zero gravity but also includes features useful in cutting and polishing of toxic or otherwise hazardous materials on Earth. Includes remote manipulator for handling specimens, cutting and polishing wire, inlets for gas and liquid, and outlets for waste liquid and gas. Replaceable plastic liner surrounds working space.

Rossier, R. N.↗
NASA NTRS1990

Workstations and gloveboxes for space station

Lockheed Missiles and Space Company is responsible for designing, developing, and building the Life Sciences Glovebox, the Laboratory Sciences Workbench, and the Maintenance Workstation plus 16 other pieces of equipment for the U.S. Laboratory Module of the Space Station Freedom. The Laboratory Sciences Workbench and the Maintenance Workstation were functionally combined into a double structure to save weight and volume which are important commodities on the Space Station Freedom. The total volume of these items is approximately 180 cubic feet. These workstations and the glovebox will be delivered to NASA in 1994 and will be launched in 1995. The very long lifetime of 30 years presents numerous technical challenges in the areas of design and reliability. The equipment must be easy to use by international crew members and also easy to maintain on-orbit. For example, seals must be capable of on-orbit changeout and reverification. The stringent contamination requirements established for Space Station Freedom equipment also complicate the zero gravity glovebox design. The current contamination control system for the Life Sciences Glovebox and the Maintenance Workstation is presented. The requirement for the Life Sciences Glovebox to safely contain toxic, reactive, and radioactive materials presents challenges. Trade studies, CAD simulation techniques and design challenges are discussed to illustrate the current baseline conceptual designs. Areas which need input from the user community are identified.

Junge, Maria↗
NASA NTRS1993

Projectile-target mixing in melted ejecta formed during a hypervelocity impact cratering event

Tektites contain little to no projectile contamination while, in contrast, some distal ejecta deposits can be relatively projectile-rich (e.g. the Cretaceous-Tertiary (K-T) boundary clay). This compositional difference motivated an experimental study of hypervelocity target-projectile mixing processes. We hope to scale up the results from these experiments and apply them to terrestrial impact structures like the Chicxulub Crater, Yucutan, Mexico, the leading contender as the site for the impact that caused the mass extinction that marks the K-T boundary. Shock decomposition of the approximately 500m thickness of anhydrite, or greater thickness of limestone, in the target rocks at Chicxulub may have been a critical mechanism for either global cooling via SO3, and subsequently H2SO4, formation, or possibly, global warming via increased CO2 formation. Understanding target-projectile mixing processes during hypervelocity impact may permit more accurate estimates of the amount of potentially toxic, target-derived material reaching stratospheric heights.

Evans, Noreen Joyce↗
NASA NTRS1994

A new material for removing heavy metals from water

The NASA Lewis Research Center developed and is patenting a new high capacity ion exchange material (IEM) that removes toxic metals from contaminated water in laboratory tests. The IEM can be made into many forms, such as thin films, coatings, pellets, and fibers. As a result, it can be adapted to many applications to purify contaminated water wherever it is found, be it in waste water treatment systems, lakes, ponds, industrial plants, or in homes. Laboratory tests have been conducted on aqueous solutions containing only one of the following metal cations: lead, copper, mercury, cadmium, silver, chromium (III), nickel, zinc, and yttrium. Tests were also conducted with: (1) calcium present to determine its effects on the uptake of cadmium and copper, and (2) uranium and lanthanides which are stand-ins for other radioactive elements, (3) drinking water for the removal of copper and lead, and (3) others compositions. The results revealed that the IEM removes all these cations, even in the presence of the calcium. Of particular interest are the results of the tests with the drinking water: the lead concentration was reduced from 142 ppb down to 2.8 ppb (well below the accepted EPA standard).

Philipp, Warren H., Jr.↗