• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.4
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• pp.9-17
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• 1994

Effect of Newtonian and non-Newtonian oils on minimum ol film thickness in engine journal bearing were investigated at various oil viscosities. The influence of oil viscosity and engine operating conditions on minimum oil film thickness of main bearing and con-rod bearing was examined. Minimum oil film thickness for Newtonian oils increased uniformly with kinematic viscosity. But the correlation between kinematic viscosity and minimum oil film thickness was very poor for non-Newtonian oils. According to the straight-line regression analysis for non-Newtonian oils, high temperature high shear viscosity at 1 $1{\times}10^6Sec^{-1}$, $150^{\circ}C$ increase the coefficient of determination from 0.41 to 0.77. Con-rod bearing showed better correlation between minimum oil film thickness and engine operating conditions than main bearing.

• Journal of the Korean Home Economics Association
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• v.11 no.2
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• pp.139-146
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• 1973

The level of serum cholesterol was successively determined for 4 weeks after the basic diet feeding for 8 weeks in the rabbits. It was observed that the individual serum cholesterol levels were highly elevated by the oral administration of cholesterol for 18 days, and then the rabbit were fed by sesame and rape seed oils for 11 weeks to survey the effect of the oils which was playing a role of decreasing factor for serum cholesterol values. The results were obtained as follows ; 1. The rabbit's serum cholesterol level was 128±29.0mg/dl in average, it was higher in female (162±50.6) than male(95±17.6). 2. It can be possible elevating experimentally the level of serum cholesterol by the cholesterol administration per os. 3. There were significant effect of the vegetable oils to decrease the experimental hypercholesteremia in the rabbits.

• Proceedings of KOSOMES biannual meeting
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• 2001.10a
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• pp.17-24
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• 2001

The sludge oils were produced necessarily in the ships operation, so that it will be the best way to manage the sludge oils inside ship itself from a viewpoint of the prevention of marine oil pollution from ship. The present study deal with the ultrasonic breaking systems which recycle the sludge oil from ships into usable oil to be burnt. The first place, experimental studies were carried out to investigate the homogenizing effect of the marine oils by repeated vibration of ultrasonic transducer. Variation of the properties(viscosity, specific gravity and pH) and the matrix structures for the environment of various marine oils were interpreted to analyze the breaking, dispersion effects by cavity. The experimental results can be useful to the development of sludge oil disposing systems.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.2
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• pp.51-57
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• 1994

Six sesame oils prepared from Korean and Chinese sesame were oxidized at 40$^{\circ}C$ for 16 weeks in a dark place. Effects of oxidative stability on tocopherols of those sesame oils were studied in related to chemical changes in the oils. All oil samples showed that the rate of tocopherol reduction was increased by the storage time. The changes of peroxide value, free fatty acid, carbonyl content were not caused in direct relation to the tocopherols oxidation. The amount of total tocopherol in the Korean sesame oil ranged from 48.7-50.3mg/100g and Chinese seseame oil ranged from 42.4-44.7 mg/100g According to the three individual tocopherols remaining content after 16weeks, ${\gamma}$-,${\alpha}$-,${\beta}$- tocopherol showed 70%, 30%, 20% of initial concentrations in the oils respectively. There was no significant difference between Korean and Chinese sesame oil except the higher total amount of the tocopherol in Korean sesame oil than that of Chinese.

• The Korean Journal of Ecology
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• v.23 no.4
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• pp.323-329
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• 2000

The allelopathic effects of volatile substances from Chamaecyparis obtusa (S. et Z.) Endl. were examined on the germination and seedling growth of some plant species, and on the population growth of some microorganisms. The germination and seedling growth of the receptor plants were suppressed more severely by leaf and fruit essential oils than by those of other parts. Colonial growth of fungi was severely inhibited by essential oils extracted from leaves and fruits. The development of root hairs of the receptor plants was also severely inhibited by the essential oils. The cortical cells at the root tips of Lactuca sativa L. treated with essential oils showed contraction of the cytoplasm, resulting in plasma membranes becoming detached from the cell walls and the cells metamorphosing irregularly. Accumulation of lipid granules inside the contracted cytoplasm and degeneration of mitochondrial cristae were also observed.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.856-860
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• 2005

Electronic-nose system was used to discriminate commercial sesame oils (A-F) extracted from imported seeds. Response (delta $R_{gas}/R_{air}$) of sensors gained from electronic nose was analyzed by principal component analysis (PCA). Flavor pattern of sesame oil A was similar to those of sesame oils B, C, and D. Sesame oils blended with corn oil at the ratio of 95:5, 90:10 and 80:20% (sesame oil/corn oil, w/w) could be discriminated from ouch genuine sesame oil.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.163-164
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• 2017

The paper is to investigate the effect of spreading of various kinds of oils on resistance to chloride attack of the normal strength concrete. Resistance to chloride attack was measured for 32 weeks and six different kinds of oils ere used. Test results indicated that resistance to chloride attack was improved in order of DSP, BD, ERBD and ERCO compared with that of Plain mixture due to filling effect of capillary pore by the use of oil.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.597-600
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• 2001

In order to investigate the electrical properties of X-ray tube oils for insulating and cooling, the breakdown characteristics in temperature range of 20∼100[$^{\circ}C$], that of AC breakdown in 0.5∼2.5(mm) of gap length, we are made researches. The classification for the physical properties of oil for X-ray tube by FTIR and $^1$H-NMR experiments was confirmed to type of mineral oils. As for the dependance of breakdown characteristics due to electrode gap length, breakdown voltage was found nearly uniform by impurity effect according to the increase of gap. As a result the characteristics for AC breakdown, the dielectric strength was increased to 90[$^{\circ}C$] but decreased over 90[$^{\circ}C$] in the temperature range.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.10
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• pp.791-797
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• 2012

Mineral insulating oils are an important insulating materials in oil-filled transformer. However, the mineral oil is the cause of the environmental problem. The vegetable oils are substitutes for mineral oil because of its biodegradability characteristic. As large size and high rating of the transformer increases, the losses increase at a faster rate. So insulating oil is forced circulation in the oil-filled transformer by using oil pumps. The flow electrification occurs when insulating oil was forced to be circulated. To check the flow electrification, had conducted experiments varying factors. As a result, the streaming electrification could see the changes according to flow velocity, oil temperature and insulation materials.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.244-245
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• 2005

Electrical insulation is one of the most important parts in a high voltage apparatus. Traditionally mineral oils and synthetic esters have been widely used as dielectric coolants for power transformers. Recently, researchers are interested in the environmental friendly vegetable oil from environmental viewpoint. This paper reports on the synthesis and characterization of soybean based ester oils. Two different types of soybean based transformer oils, named as methyl ester and isopropyl ester were synthesized. The synthesis of these esters was achieved by transesterification reactions of soybean oil and alcohol in the presence of catalyst. The GC and NMR spectroscopic analysis of the esters have been performed. The thermal stability of the esters was determined by thermal gravimetric analysis(TGA).