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21.
Aromaticities determined by 13C n.m.r. are reported for five shale oil samples (Green River formation) prepared under widely different pyrolysis conditions. In the absence of high-pressure hydrogen, the total amount of aromatic carbon in the products is nearly twice that in the raw shale. This is true for a wide range of pyrolysis conditions, although the distribution of aromatic carbon between the oil and carbonaceous residue changes. High-pressure hydrogen appears to inhibit both the formation of additional aromatic carbon during pyrolysis and the coking of aromatic oil. An improved kerogen decomposition mechanism is reported that accounts for these effects and provides for changes in the aromaticity of the liquid product with pyrolysis conditions. Further work is necessary to make it quantitative and account for gas formation. 相似文献
22.
A. C. Lanser G. R. List R. K. Holloway T. L. Mounts 《Journal of the American Oil Chemists' Society》1991,68(6):448-449
A user-interactive computer-assisted Fourier transform infrared (FTIR) method has been developed for estimation of free fatty
acids (FFA) in vegetable oil samples by deconvolution of the infrared (IR) absorbances corresponding to the triglyceride ester
and FFA carbonyl bonds. Peak areas were used to determine FFA as a percentage of the total carbonyl areas in weighed standards
of refined, bleached, deodorized soybean oil containing from 0 to 5% added oleic acid. These data for percent FFA by FTIR
were compared to corresponding FFA data obtained by two titration methods-the AOCS Official Method Ca 5a-40 and the Official
Method with a slight modification. Correlation coefficients were 0.999 for the Ca 5a-40, 0.999 for the modified and 0.989
for the FTIR methods. FFA in samples of crude soybean oils extracted from damaged beans (0.5 to 2.1% FFA) were measured by
FTIR and compared to data obtained by titration of the same samples (correlation coefficient, 0.869).
To whom correspondence should be addressed at National Center for Agricultural Utilization Research, Agriculture Research
Service, U.S. Department of Agriculture, 1815 North University Street, Peoria, IL 61604.
1The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of
Agriculture over other firms or similar products not mentioned. 相似文献
23.
As part of a study of the chemistry of the steam-stimulated recovery of heavy oils, the hydrolysis and subsequent desulphurization of tetrahydrothiophene and thiophene by aqueous solutions of vanadyl and nickel salts was investigated. Vanadyl sulphate and vanadyl chloride were shown to behave very differently, emphasizing that these salts have different molecular species in aqueous solutions. 相似文献
24.
The relationship between chemical structure and reactivity for thermal hydroprocessing was studied for five gas oils derived from Alberta bitumens. Chemical structure was characterized by combining data from 1 H and 13 C nuclear magnetic resonance spectroscopy, class fractionation, and elemental analysis to calculate structural parameters. Thermal hydrotreating was performed in a continuous-flow stirred reactor at 420 and 440°C, 13.9 MPa hydrogen pressure, and 1.5 h1 LHSV. Conversion of the 343–525°C boiling fraction of the gas oils was correlated with the concentration of naphthenic methylene groups in the feed. Formation of methane and ethane was dependent on the degree of condensation of the aromatic rings in the feed oils. Thermal desulfurization was highly correlated with the amount of saturates in the feed, and the aromaticity of the resin fraction. Hydrogen consumption increased with the aromaticity of the gas oil… 相似文献
25.
26.
A rapid test to measure performance,emission and wear of a diesel engine fueled with palm oil diesel
H. Masjuki A. M. Zaki S. M. Sapuan 《Journal of the American Oil Chemists' Society》1993,70(10):1021-1025
Results of performance, emission and tribological evaluations of palm oil methyl ester and its blends with conventional diesel
in an automobile diesel engine test bed are presented. Polymerization and carbon deposits on the fuel injector were monitored.
CO, CO2, O2, combustion efficiency and temperature of exhaust gases were also measured. Palm oil methyl ester and its blends have great
potential as alternative diesel fuel. Performance and exhaust gas emission for palm oil methyl ester and its blends with conventional
diesel are comparable with those of conventional diesel fuel. Palm oil methyl ester does not pose a severe environmental problem
and will not deteriorate engine and bearing components. 相似文献
27.
L. Di Giovacchino F. Angerosa L. Di Giacinto 《Journal of the American Oil Chemists' Society》1996,73(3):371-374
Variable quantities of leaves were added to ripe olives prior to extraction to determine their effect on the quality of the
resulting olive oil. The addition of 1–3% w/w leaves improved the organoleptic quality. An increase intrans-2-hexenal aldehyde content occurred, giving the pleasant flavor of “freshly cut grass.” This compound was produced by the
enzymatic breakdown of 13-L-hydroperoxide of linolenic acid in leaf homogenates. 相似文献
28.
29.
R. Baixauli A. Salvador S. M. Fiszman C. Calvo 《Journal of the American Oil Chemists' Society》2002,79(11):1127-1131
Oil degradation caused by the number of fryings performed and the effect of oil degradation on the color of fried battered
squid rings were studied. Spectrophotometric techniques with absorbance in the UV and visible ranges, and iodine, peroxide,
and acid values were used to determine oil degradation. Determination of various CIELAB parameters in order to study the external
color of the fried battered squid rings revealed no differences in color due to the number of fryings. A study of the color
of the battered squid rings at various frying times and temperatures showed significant differences for both variables. Although
there was some degradation in the oil after 20 fryings, appearing as a slight darkening, it did not affect the final color
of the fried, battered squid rings. 相似文献
30.
Bleached and unbleached forms of a rosemary oleoresin (RO) in stripped and nonstripped soybean oil behave both as antioxidant
and prooxidant in a light-induced oxidative system. At 0.02 and 0.05% levels, RO had the greatest antioxidant activity, while
at 0.01 and 0.5% levels it had the highest prooxidant activity in both stripped and nonstripped soybean oil. Treatment of
both soybean oil systems with tertiary butylhydroquinone controlled light-induced oxidation of the oil better than did the
oleoresin treatments. The prooxidant activity of the 0.5% RO level was probably due to an excess of prooxidant components
being carried into the oil at that level, whereas the reduced antioxidant activity at 0.01% was probably due to the low initial
level of active antioxidant components being added to the oil.
Published as Journal Series No. 10072, Nebraska Agricultural Research Division, Department of Food Science and Technology,
University of Nebraska, Lincoln, NE 68583-0919. 相似文献