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Abiotic synthesis of meteoritic aliphatic hydrocarbons produced by open flow Fischer- Tropsch processes for hydrogen and Co interactions
Antiwear and extreme pressure additive effects during bearing spinning with synthesized hydrocarbon oils
Paraffinic hydrocarbons in tobacco tissue cultures
Degradation of hydrocarbon polymers by exposure to 275 F for 400 hours in presence and in absence of ammonium perchlorate
Extraterrestrial abiotic amino acids and hydrocarbons in type II carbonaceous chondrite at Murchison, Australia
Synthesized hydrocarbon oil antiwear and extreme pressure additives effects on bearing spinning torque and endurance
Type III carbonaceous chondrite Murchison meteorite, obtaining amino acids, aliphatic and aromatic hydrocarbons from specimen
Hydrocarbons pyrolysis in Knudsen cells at low pressures, using mass spectrometry to study reactions and products
Polynuclear aromatic hydrocarbons in Murchison meteorite, determining distribution by gas chromatography and mass spectrometry
Internal short chain alkane populations of paraffinic hydrocarbons in tobacco teratoma and habituated tissue cultures
Two short turbojet combustors designed for use with vaporized hydrocarbon fuels were tested in a one-quarter annular duct. The experimental combustors consisted of many small "swirl-can" combustor elements manifolded together. This design approach allowed the secondary mixing zone to be considerably reduced over that of conventional combustors. The over-all combustion lengths, for the two configurations were 13.5 and 11.0 inches, approximately one-half the length of the shortest conventional combustors. These short combustors did not provide combustion efficiencies as high as those for conventional combustors at low pressures. However, over the range of combustor-inlet total-pressures expected in aircraft capable of flight at Mach numbers of 2.5 and above, these short combustors gave very high efficiencies. A combustion efficiency of 97 percent was obtained at a combustor-inlet total-pressure of 25.0 inches of mercury absolute, reference velocity of 120 feet per second, and inlet-air total temperature of 1160 deg R. By proportioning the fuel flow between the manifold rows of can combustor elements, control of the combustor-outlet radial total-temperature profile was demonstrated. Combustor totalpressure loss varied from 0.75 percent of the inlet total pressure at isothermal conditions and a reference velocity of 75 feet per second to 5.5 percent at a total-temperature ratio of 1.8 and a reference velocity of 180 feet per second.
The Murchison meteorite contains aliphatic and aromatic hydrocarbons similar to those made in static Fischer-Tropsch-type syntheses. Principal compound classes above C8 are n-alkanes, mono- and dimethylalkanes, alkenes, alkylbenzenes and -naphthalenes. Below C8, n-alkanes are virtually absent; instead, benzene, toluene, branched alkanes dominate. The CH4/C2H6 ratio is greater than 30, possibly greater than 700. Isoprenoids from C17 to C20 occur in a surface rinse but not in subsequent extracts and appear to be terrestrial contaminants. Thiophenes, porphyrin-like pigments, and chlorobenzenes were also found; the latter appear to be contaminants. In the Allende meteorite, only methane, benzene, toluene and an aromatic polymer seem to be indigeneous. A comprehensive review of current evidence shows that Fischer-Tropsch-type reactions can account for most principal features of meteorite organic matter.
The paper reports on the study of auto-ignition of hydrocarbon-oxygen mixtures behind reflected shock waves. Because of their bearing on the problem of knock in internal combustion engines, n-heptane and iso-octane were chosen as the combustible species. Their stoichiometric mixtures with oxygen had to be diluted with 70% argon to reduce the influence of the boundary layer. Photographic records demonstrated the existence of two different modes of ignition, as has been previously established for the hydrogen-oxygen system. The pressure-temperature limits between these regions of mild and strong ignition were determined. From the same experimental tests, induction time data were obtained over the pressure range of 1-4 atm and the temperature interval of 1200-1700 K.
A series of DEAB initiated isoprene polymerizations were run in the 5-gallon stirred autoclave reactor. Polymerization run parameters such as initiator concentration and feed rate were correlated with the molecular weight to provide a basis for molecular weight control in future runs. Synthetic methods were developed for the preparation of n-1,3-alkadienes. By these methods, 1,3-nonadiene was polymerized using DEAB initiator to give an ester-telechelic polynonadiene. This was subsequently hydrogenated with copper chromite catalyst to give a hydroxyl terminated saturated liquid hydrocarbon prepolymer having greatly improved viscosity characteristics and a Tg 18 degrees lower than that of the hydrogenated polyisoprenes. The hydroxyl-telechelic saturated polymers prepared by the hydrogenolysis of ester-telechelic polyisoprene were reached with diisocyanates under conditions favoring linear chain extension gel permeation chromatography was used to monitor this condensation polymerization. Fractions having molecular weights above one million were produced.
The paper describes the disk machine designed and constructed for the investigation of the traction in elastohydrodynamic line contacts for two synthesized hydrocarbon fluids. The results of this experimental study are presented and compared with the theoretical predictions of traction according to the thermal and non-Newtonian theory recently presented by the authors.
A hydrocarbon-utilizing Brevibacterium which grew into the oil phase of an oil-water system was tested for survival at elevated temperature. Cells suspended in oil and cells that had been resuspended in aqueous solution were tested by placing 1-ml samples of the cell suspension in small test tubes immersed in a controlled-temperature water bath. The resultant survival curves in oil consisted of two parts, a flat shoulder obtained in the first half of the heating period, followed by a break indicating rapid die-off. The break in the curves occurred after 50% of the cells were killed. This occurred at exposures of 25, 15, and 8 min for 78, 88.6, and 96.2 C, respectively. The survival curve for 63.5 C in the aqueous solution was a rapid, exponential die-off. The actual increase in survival of the organism in oil is reflected by the length of the shoulder portion. The shoulder occurs only in an oil medium and is increased by decreasing temperature and increasing age of the culture.
The high-molecular-weight constituents of the branched and cyclic hydrocarbon fraction of the Messel oil shale (Eocene) have been examined by high-resolution gas chromatography and combined gas chromatography/mass spectrometry. The following compounds are present: perhydrolycopene, together with one or more unsaturated analogs with the same skeleton; a series of 4-methylsteranes in higher abundance than their 4-desmethyl analogs; two series of pentacyclic triterpanes, one series based on the hopane structure, and the other based on the 17 alpha-H hopane structure; and an intact triterpene hop-17(21)-ene. Only two additional triterpanes were detected in minor concentrations - namely, 30-normoretane and a C31 triterpane based on the hopane/lupane-type skeleton. The presence of these compounds suggests a significant microbial contribution to the forming sediment.
The possibility of catalytic destruction of H by C2H2 in the Jovian upper atmosphere is investigated, and other photochemical hydrocarbon reactions are presented. It is shown that the catalytic action of C2H2 can destroy or preserve atomic hydrogen, depending on the branching ratio of an intermediate reaction and the temperature dependence of various reaction rates. A model Jovian atmosphere is constructed, and the altitude profiles of some species are plotted. It is noted that this model has a greater atomic hydrogen abundance and a lower concentration of C2H2 than previous ones, and that the H profile should be considered as an upper limit for the Jovian atmosphere.