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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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Life detection for space missions based on detecting optical asymmetry in biogenic molecules by gas chromatography involving diastereomeric esters synthesis
Linear aliphatic polyesters preparation by acid chloride synthesis, acid exchange and ester exchange, stressing products purification
Transesterification of amino acid peptide alkyl and fatty acid esters by treatment with anion- exchange resin
Shingle-type, crinkled, aluminized polyethylene ester is thermally and structurally tested for cryogenic insulation. Insulation systems require thermal efficiency with minimum weight, and the ability to withstand vibration, acceleration, and rapid pressure drops.
General procedure and molding sand composition for preparing molds usable for casting variety of alloys are developed. Molds are prepared from mixture of sand, sodium silicate binder, and organic liquid ester. Castings of radiographic quality are produced from various alloys.
Hydroxy fatty acid methyl esters gas chromatography and mass spectrometry, noting trimethylsilylation usefulness for locating double bond
Helical twisting power of steroidal solutes in cholesteric mesophases, discussing nematic temperature shift dependence on ester chain
Gas-liquid chromatographic separation applied in derivatization chemistry of protein amino acids as N-trimethylsilyl /TMS/ esters
Butyl esters separation from protein amino acids, using acid washed Chromosorb W of various mesh sizes
P32 labeled organic phosphate esters in water extracts of soil
Quantitative gas-liquid chromatography of histidine, using N-TFA n-butyl ester derivatives and histidine converted trimethylsilyl derivative
Investigating ester and alkyl compounds as lubricating oils for use with liquid oxidizers
Steel friction and wear tests in nitrogen with paraffinic resins, synthetic paraffinic oil, glycol, and ester lubricants including thermal stability at high temperatures
Life detection for space missions based on detecting optical asymmetry in biogenic molecules by gas chromatography involving diastereomeric esters synthesis
Synthesized amino esters and ketones with varying distance between functionalities, examining mass spectral fragmentation
Amidoximes dehydration with and without rearrangement, suggesting carbodiimide formation from O-benzenesulfonyl ester
The monomeric reactants approach was used to fabricate addition-type polyimide/graphite fiber composites with improved mechanical properties and thermal stability characteristics over those of composites derived from addition-type amide acid prepolymers. A screening study of 24 different monomer combinations was performed. The results of a more extensive investigation of a selected number of monomer combinations showed that the combination providing the best thermomechanical properties was 5-norbornene-2.3-dicarboxylic acid monomethyl ester/4,4(')-methylenedianiline/3,3(')4,4(')-benzophenonetetracarboxylic acid dimethyl ester at a molar ratio of 2/3.09/2.09.
Various flexible polyurethane structures containing halogen were synthesized from polyesters derived from aliphatic or aromatic polyols and dibasic acids. Aliphatic halide structures could not be used because they are unstable at the required reaction temperatures, giving of hydrogen halide which hydrolyzes the ester linkages. In contract, halogen-containing aromatic polyols were stable and satisfactory products were made. The most promising composition, a brominated neopentyl glycol capped with toluene disocyanate, was used as a conventional diisocyanate, in conjunction with hydroxy-terminated polyethers or polyesters to form elastomeric urethanes containing about 10% bromine with weight. Products made in this manner will not burn in air, have an oxygen index value of about 25, and have tensile strength values of about 5,000 psi at 450% elongation. The most efficient additives for imparting flame retardancy to Spandex urethanes are aromatic halides and the most effective of these are the bromide compounds. Various levels of flame retardancy have been achieved depending on the levels of additives used.