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Chemical synthesis of monomeric self-sealant type esters Status report
Synthesis of alkyl esters of alpha-cyanosorbic acid for self-sealing polymerization
The synthesis of alpha-amino acid menthyl esters. II.
Synthesis of alpha-amino acid l-menthyl esters under mild conditions, using alpha-amino acid N- carboxy anhydride /NCA/ and l-menthol
Resolution of neutral DL-amino-acids via their /--/-menthyl ester derivatives.
Resolution method for DL-amino-acids via menthyl ester derivatives and gas-liquid chromatographic analysis of crystalline products
Stereoselective syntheses of optically active amino acids from menthyl esters of alpha-keto acids.
Stereoselective synthesis of optically active amino acids from menthyl esters and alpha-keto acids
Preliminary determinations of temperature limitations of ester, ether, and hydrocarbon base lubricants in 25-mm bore ball bearings
Temperature limitations of polyphenyl ethers, esters, and hydrocarbon base lubricants in small bore ball bearings
Stereoselective Syntheses of Optically Active Amino Acids from Methyl Esters of Alpha-keto Acids
Stereoselective syntheses of optically active amino acids from methyl esters of alpha-keto acids
The catalytic hydrolysis of phosphate ester bonds by thermal polymers of amino acids.
Catalytic hydrolysis of phosphate ester bonds by proteinoids /thermal polymers of amino acids/, discussing effects of enzyme inhibitors on reaction
Effect of oxygen concentration on an advanced ester lubricant in bearing tests at 400 deg and 450 deg F
Oxygen concentration effects on ester lubricant degradation during high temperature bearing test
Effect of oxygen concentration on synthetic paraffinic and advanced ester base lubricants in bearing tests at 400 deg and 450 deg F.
Oxygen concentration effects on oxidation of synthetic paraffinic and type II ester lubricants determined from ball bearing tests at 400 and 450 degrees F
Syntheses of optically active alpha-amino acids from esters of alpha-keto acids by hydrogenolytic asymmetric transamination - A solvent effect
Optically active alpha-amino acids synthesis from esters of alpha-keto acids by hydrogenolytic asymmetric transamination
Direct esterification of the protein amino acids gas-liquid chromatography of N-TFA n-butyl esters
Gas-liquid chromatography studies of direct esterification of protein amino acids to n-butyl esters
Fatty acid ethyl esters of Rhizopus arrhizus
Ethyl esters of long chain fatty acids as biological products from gas chromatographic and mass spectrometric analyses on lipid fractions
Studies of the acidic components of the Colorado Green River formation oil shale-Mass spectrometric identification of the methyl esters of extractable acids.
Study of solvent extractable acidic constituents of oil shale from the Colorado Green River Formation. Identification of individual components is based on gas chromatographic and mass spectrometric data obtained for their respective methyl esters. Normal acids, isoprenoidal acids, alpha, omega-dicarboxylic acids, mono-alpha-methyl dicarboxylic acids and methyl ketoacids were identified. In addition, the presence of monocyclic, benzoic, phenylalkanoic and naphthyl-carboxylic acids, as well as cycloaromatic acids, is demonstrated by partial identification.
Measurements of the Michigan Airglow Observatory from 1971 to 1973 at Ester Dome Alaska
The Michigan Airglow Observatory (MAO) was located at Ester Dome Observatory, College, Alaska (latitude: 64 deg 53'N, longitude: 148 deg 03'W) since October, 1971. The MAO houses a 6-inch Fabry-Perot interferometer, a 2-channel monitoring photometer and a 4-channel tilting filter photometer. The Fabry-Perot interferometer was used extensively during the winter observing seasons of 1971-72 and 1972-73 to measure temperature and mass motions of the neutral atmosphere above approximately 90 kilometers altitude. Neutral wind data from the 1971-72 observing season as measured by observing the Doppler shift of the gamma 6300 A atomic oxygen emission line are presented.
Correlation of elastohydrodynamic film thickness measurements for fluorocarbon type 2 ester, and polyphenyl ether lubricants
A minimum films thickness correlation applicable to heavily loaded elastohydrodynamic (EHD) contacts was formulated from experimental data obtained by an X-ray transmission technique. The correlation, based on data generated with fluorocarbon, type II ester, and polyphenyl ether lubricants, extends a previous analysis developed from data for a synthetic paraffinic oil. The resulting correlation represents the data of the four lubricants reasonably well over a large range of operating conditions. Contained within the derived relation is a factor to account for the high-load dependence displayed by the measurements beyond that which is provided for by the theory. Thermal corrections applied to a commonly used film thickness formula showed little improvement to the general disagreement that exists between theory and test. Choice of contact geometry and material are judged to have a relatively mild influence on the form of the semiempirical model.
Stereoselective formation of a 2 prime (3 prime)- aminoacyl ester of a nucleotide
Reaction of DL-series and adenosine-5-phosphorimidazolide in the presence of adenosine-5'-(0-methylphosphate) and imidazole resulted in the stereoselective synthesis of the aminoacyl nucleotide ester, 2'(3')-0-seryl-adenosine-5'-(0-methylphosphate). The enantiomeric excess of D-serine incorporated into 2'(3')-0-seryl-adenosine-5'-(0-methylphosphate) was about 9%. Adenylyl-(5->N)-serine and an unknown product also incorporated an excess of D-serine, however, seryl-serine showed an excess of L-serine. The relationship of these results to the origin of the biological pairing of L-amino acids and nucleotides containing D-ribose is discussed.
Development and Preliminary Evaluation of Aryl Ester Boundary Additives for Perfluoropolyethers
A series of additives were developed for evaluation as boundary lubrication enhancers for perfluoropolyethers. They are composed of a hydrocarbon aryl component (for lubrication improvement) and a fluorinated side chain (for solubility enhancement). The two moieties are joined by an ester linkage. Five boundary additives were evaluated in a perfluoropolyether basestock (Fomblin Z25) using a specially designed four-ball apparatus. Additives were evaluated at a one wt percent concentration. Conditions included: an atmosphere of dry air at atmospheric pressure, a 200N load, a speed of 100 rpm, room temperature, and 440C stainless steel specimens. Two monoesters, 2,4,6-trimethyl E2 and H5PDFO yielded wear rate reductions of approximately 60 and 35 percent, respectively. One diester, H4(E2)(sub 2), had no activity, while two other diesters (a diester of bisphenol A and H4(E4)(sub 2)) were pro-wear.