2:00 PM - 2:15 PM
[PPS12-14] Chemistry of formaldehyde and ammonia in the Solar System small bodies
Keywords:Meteorites, Asteroids, Organic matter
Each starting solution contained 1mL water with 2 mmol formaldehyde, 1 mmol glycolaldehyde, 0.4 mmol ammonia (equivalent to H2O : C : N = 100 : 7.2 : 0.72) with catalytic amount of Ca(OH)2, and was sealed in a glass tube, then isothermally heated at 90 degrees C up to 250 degrees C. XANES and FTIR analyses showed that aromatic or olefinic C=C bond abundance increased with temperature in the soluble fractions. This indicates that the insoluble residues precipitate as a result of increase in the hydrophobic moieties in the products as the reaction proceeds. This is consistent with the previous results that the amount of insoluble fractions (organic solids) increases with temperature . Acid hydrolysis of the solutions produced various amino acids up to four carbons. Alanine abundance was larger than glycine, and may indicate high abundance of methyl (-CH3) or methylene (-CH2-) substitutions in the amino acid precursor molecules. ESI-MS results suggested that various carbohydrates (CHO molecules) and these with nitrogen containing substitutions. This is somewhat consistent with ultrahigh-resolution ESI-MS analysis of the Murchison meteorite extract that shows various CHO and CHNO molecules , although only formaldehyde and ammonia chemistry cannot explain all of the diverse molecules found in this meteorite.
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