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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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Design and modification of pyrolysis, gas chromatograph, double focusing mass spectrometer and addition of heated ion source for Martian life detection
Energy transfer in pyrolysis product flow through char layer of nylon phenolic resin ablator
Flame spreading velocity characteristics over solid fuel surfaces, discussing environmental pressure, chemical reactivity, pyrolysis, forced convection, etc
Pueblo de Allemande chondrite unexctractable carbon content using meteorite pyrolysis, obtaining aromatic hydrocarbons
Polymer structure and cross-link density effects on thermal analysis of phenol-formaldehyde polymers pyrolysis products
Apollo 11 lunar samples organic carbon content analysis by pyrolysis hydrogen flame ionization detection
Volatilizable C compounds in lunar fines from Mare Tranquillitatis, investigating pyrolysis and acid hydrolysis products by mass spectroscopy and gas chromatography
Pulsed ruby laser mass spectrometry technique for flash pyrolysis of ammonium perchlorate-catalyst mixtures
Large diameter graphite/carbon composite monofilaments produced by pyrolysis
Analysis of reacting flow of pyrolysis products through char layer of low density, nylon phenolic resin, charring ablators and porous graphite
Ablative heat shield char layer, examining reacting nonequilibrium pyrolysis gas flow
Apollo 12 sample 12023 fines carbon, carbides and methane determination by hydrolysis and vacuum pyrolysis
Nonequilibrium modeling of pyrolysis gas products flow through char layer of ablative heat shield
Carbon compounds in Apollo 12 lunar fines and core samples, using pyrolysis, mass spectrometry, ion exchange chromatography and optical and electron microscopy
Apollo 12 lunar surface samples analysis for organic compounds by mass spectroscopy and pyrolysis-gas chromatography
The overall program objective was to develop a flexible compound which not only functioned in a manned aerospace environment as an effective electrical insulation, but whose flammability characteristics in 16.5 psia, 60% oxygen/40% nitrogen were evidenced by rapid self-extinguishment and minimal thermal (pyrolysis) degradation. The following polymeric matrices were examined in depth: fluoroelastomers, modified fluoroelastomers, silicone RTV's, and modified silicone and fluorosilicone RTV's. Almost none of these systems burned in air, but all burned in 6.2 psia oxygen. Inorganic, organic, and inorganic/organic additives were evaluated in conjunction with these polymers in order to achieve the required survival in the 16.5 psia 60/40 environment. Depending upon formulations, it was possible to achieve nonflammable products when tested in the 1/4 in. x 1/4 in. x 1 in. configuration, even up to and including 16.5 psia oxygen. However, in order to assure this level of flame resistance, it was found necessary to heavily load the matrix with the additives. This resulted in a significant reduction in mechanical properties and large increases in viscosities. Optimization of formulations to obtain a suitable balance between these properties and flammability resistance led to the final selection of Formulation 387 as the primary system.
A prototype all carbon triode ultrahigh vacuum gage was fabricated and tested. The gage exhibited a sensitivity of 3.7 per torr for nitrogen and an X-ray background approximately 0.1 as large as would be expected of a metal gage of the same design. The gage made from these materials, showed good sensitivity and durability. A practical technique was developed for bonding carbon components together without metal fasteners. The bond is made with a cross-linked phenolic resin which is converted to vitreous carbon by a careful pyrolysis procedure. The resulting bonds are strong, electrically conductive, and can withstand repeated excursions to 2500 K in vacuum. Measurements of adsorption and outgassing characteristics of four refractory carbons have confirmed that such materials are suitable for use in ultrahigh vacuum and that some are superior refractory metals in man respects.
An analytical study of the theory of ignition and burning of a plastic material immersed in an atmosphere of a space cabin which may be subjected to gravity force changes is considered. The hazardous condition in a space cabin environment where the changes of gravity may effect the combustion process is evaluated. The model considered the analysis of the coupled gas and solid phases and is based on the premise that material heating leads to the formation of pyrolysis gases from the decomposed solid which then react with the ambient oxidizer to further the combustion process. Moreover, free convection plays a dominant role in transporting these hot gases to the virgin material. A time-dependent study of the coupled gas-solid model as required for ignition processes with emphasis on the surface energy interchange of the gas and solid phases has been made. Detailed distribution of species composition and temperature patterns provide a spatial and time map of the evolving gases from the material combustion.