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91.
92.
针对油封的大批量、多品种、流水线作业的生产特点以及"零废品率"的检测要求,利用机器视觉检测和计算机图象处理技术,研究开发了适应大批量生产和在线实时检测的油封尺寸机器视觉检测系统;建立了系统软硬件结构,分析了系统的组成和工作原理及工作过程,并对图像处理算法进行了设计;系统标定后的实验检测结果证明,该检测系统能实现产品100%检测的生产目标,具有非接触、在线实时、精度适中、成本低等特点,具有较好的生产通用性。 相似文献
93.
Assessment of contaminant releases during utilization of used oils is essential for the determination of environmental acceptability. These paper reports the results of the study examining a toxic metal leachability from used engine oil and sludge samples employing leaching test (TCLP). The leaching test indicated that lead in oil samples exceeded 5-ppm concentration level what qualified them as a toxic waste. The samples of contaminated sludge were found to contain high concentration of total lead, barium and chromium, but the leaching test showed concentration below regulatory limit. The total content of benzene, ethylbenzene, toluene, and xylenes (BETX), and naphthalene in used oil and sludge samples was also determined and was found not to be a significant factor to contamination. 相似文献
94.
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
95.
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
96.
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
97.
W. D. Branch T. Nakayama M. S. Chinnan 《Journal of the American Oil Chemists' Society》1990,67(9):591-593
Fatty acid composition was determined among seven U.S. runner-type peanut (Arachis hypogaea L.) cultivars: Florunner, Sunrunner, GK-7, Southern Runner, Sunbelt Runner, Okrun, and Langley. Significant year and cultivar
differences were found within these fatty acid profiles. Southern Runner had the best oleic to linoleic ratio and iodine values;
whereas Florunner, Sunrunner, and Langley were the highest in unsaturated and lowest in saturated and long-chain fatty acids.
For the future, breeding programs need to continue developing peanut cultivars with improved oil quality. 相似文献
98.
99.
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
100.