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Gibson, E. K.

Publications and source records attributed to Gibson, E. K..

59 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

An evaluation: The potential of discarded tires as a source of fuel

The destructive distillation of rubber tire samples was studied by thermogravimetry, differential scanning calorimetry, combustion calorimetry, and mass spectroscopy. The decomposition reaction was found to be exothermic and produced a mass loss of 65 percent. The gas evolution curves that were obtained indicate that a variety of organic materials are evolved simultaneously during the decomposition of the rubber polymer.

Collins, L. W.↗
NASA NTRS1974

An evaluation of discarded tires as a potential source of fuel

The destructive distillation of rubber tire samples was studied by thermogravimetry, differential scanning calorimetry, combustion calorimetry, and mass spectroscopy. The decomposition reaction was found to be exothermic and produced a mass loss of 65%. The products from the distillation process were a solid residue with a heating value of about -30 MJ/kg, a liquid with a heating value of about -40 MJ/kg, and a combustible gas of undetermined heating value. The gas evolution curves which were obtained indicate that a variety of organic materials are evolved simultaneously during decomposition of the rubber polymer.

Collins, L. W.↗
NASA NTRS1972

The origin and stability of lunar goethite, hematite and magnetite.

Extra-lunar contamination, fumarolic activity, and exposure to oxidizing gases from comet or carbonaceous meteorite impacts have been previously proposed as the causes of magnetite, hematite, and goethite in lunar materials. However, these minerals can occur in the stable low-temperature gas-solid equilibrium assemblages of lunar rocks. Below 600 C magnetite is in equilibrium with C-O-H gases with compositions compatible with high-temperature equilibrium with metallic iron; below 150 C hematite is stable in these same gases. Goethite is not stable in carbonaceous gases at low total pressure, and thus gases from impacting carbonaceous material cannot have produced it. Goethite is stable at low temperatures and pressures in almost pure H2-H2O gases. Its minimum stability against hematite is 2 bars total pressure at 130 C and 0.001 bars at 30 C for H2 to H2O ratios compatible with the high-temperature redox state of lunar materials. Thus the traces of magnetite, hematite, and goethite in lunar materials may be the result of normal low-temperature processes indigenous to the moon and not special processes.

Williams, R. J.↗