• Applied Biological Chemistry
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• v.41 no.8
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• pp.578-582
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• 1998

Grape seed oil was characterized to assess the usefulness in the food industry. Among the various oils, the initial antioxidant activity was the highest for grape seed oil. Heating the oil at $180^{\sim}C$ for 20 min retained 86% of the initial activity. Grape seed and sesame oils showed a low peroxide value, about 2, implying a less oxidative reaction. The oxidation of grape seed oil was increased to a less extent by heat-treatment than other oils. Light exposure for 1 month resulted in a slight decrease in the antioxidant activity of grape seed oil, maintaining 96% of the initial activity. Other oils were all light-susceptible and the activities decreased significantly. The peroxide values of all the oils increased by light exposure, but the extent of oxidation was still the least for grape seed oil. The addition of grape seed oil to perilla oil was very effective, in that the peroxide value was 5-times decreased by 1 : 5 composition of grape seed oil versus perilla oil. These results indicate that grape seed oil can be used as a good cooking oil or an additive for other oils.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.337-341
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• 2002

Crude seasoning oil was manufactured from direct heat treatment of com germ, wheat germ, dehulled peanut, mustard, black pepper and com oil(RBD type). The sesame oil substituted was composed of this crude seasoning oil, oil soluble natural pigment mixture and com oil, and showed the similar appearance, flavor and taste with sesame oil. Free fatty acid content of SO was 1/4 than sesame oil, the other values were similar, respectively. Use of this SO was suitable about cooking, general frying as well as frying of laver and Chinese cake. As a result, this SO had possiblility as sesame oil substituted.

• Transactions of Materials Processing
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• v.11 no.3
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• pp.211-216
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• 2002

The mechanical and thermal load, and thermal softening occuring by the rush temperature of die, in warm and hot forging, cause wear, heat cracking and plastic deformation, etc. This paper describes the effects of solid lubricants and surface treatments for warm forging die. Because cooling effect and low friction are essential to the long life of dies, optimal surface treatments and lubricants are very important to hot and warm forging process. The main factors affecting die hardness and heat transfer, are surface treatments and lubricants, which are related to heat transfer coefficient, etc. To verify the effects, experiments are performed for heat transfer coefficient in various conditions - different initial billet temperatures and different loads. Carbonitriding and ionitriding are used as surface treatments, and oil-base and water-base graphite lubricants are used. The effects of lubricant and surface treatment for warm and hot forging die life are explained by their thermal characteristics, and the new developed technique in this study for predicting tool life can give more feasible means to improve the tool life in hot forging process.

• Journal of the Korean Society for Heat Treatment
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• v.28 no.6
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• pp.300-309
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• 2015

The aim of the present study was to predict the variations in microstructure and deformation occurring during gas carburizing and quenching processes of a SCM420H planetary gear in a real production environment using the finite element method (FEM). The motivation for the present study came from the fact that previous FEM simulations have a limitation of the application to the real heat treatment process because they were performed with material properties provided by commercial programs and heat transfer coefficients (HTC) measured from laboratory conditions. Therefore, for the present simulation, many experimentally measured material properties were employed; phase transformation kinetics, thermal expansion coefficients, heat capacity, heat conductivity and HTC. Particularly, the HTCs were obtained by converting the cooling curves measured with a STS304 gear without phase transformations using an oil bath with an agitator in a real heat treatment factory. The FEM simulation was successfully conducted using the aforementioned material properties and HTC, and then the predicted results were well verified with experimental data, such as the cooling rate, microstructure, hardness profile and distortion.

• Plant Journal
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• v.4 no.4
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• pp.56-61
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• 2008

The phenomena of oil whip in steam turbines take place for the unbalance force between a rotor shaft and bearing oil film. The several parameters that affect onset of oil whip have been well known. However, the major parameter of oil whip is shaft mis-alinement. A oil whip causes the high vibration and the shutdown of rotor system. We mostly stop the steam turbine to adjust a shaft re-alinement concerning oil whip. In this case, it needs many costs for maintenance and long shutdown times. In this study, we study and observe the oil whip of the 300MW steam turbine in many years and we conduct the field test for another steam turbine for reducing vibration from oil whip. The results of this study are that a oil whip takes place with a particular rotating speed or a particular turbine output and the oil temperature change is a very effective method for on-line oil whip treatment.

• Journal of Ocean Engineering and Technology
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• v.23 no.3
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• pp.30-34
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• 2009

Oil hydraulic piston pumps are being extensively used in the world, because of simple design, light weight and effective cost etc. An oil hydraulic pump is likely to have serious problems of high leakage, friction and low energy efficiency according to large time use. In the oil hydraulic piston pumps the clearance between the valve block and piston plays an important role for volumetric and overall efficiency. In this paper, the wear property of the SACM645 material used the hydraulic piston pump has been work out by experimentation with variable heat treatment. To investigate the effect according to the piston surface condition, seven different types specimen were prepared. From the wear test results, induction hardening and nitration were definitely superior to the others. On the whole, nitration was estimated for high strength material to wear resistance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.495-497
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• 1999

In order to determine what influences the interfacial breakdown in EPDM/XLPE laminates, We made the breakdown test ceil and this was pressure controllable breakdown test cell. We make the needle electrode (tip radius: about 10 micrometer) using electrochemical method. We studied the interfacial silicone oil was higher than that with silicone grease. As a function of heat treatment time in a vacuum, interfacial breakdown strength increased much in XLPE/EPDM laminates pasted with silicone grease but increased a little in that with silicone oil.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.150-155
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• 1999

The possibility of grape seeds as industrial resources was tested by analyzing various chemical proper-ties of their oils from seven different species. The range of crude oil content of the grape seeds was 26.0-32.0% showing the highest content in Steuden, Mean individual fatty acid contents in the grape seeds were lioleic (70.75%) oleic (18.48%) stearic (2.01%) and palmitic (8.45%) acids. Stearic acid was low in Jingyu and high oleic acid was found in Fugiminori compared with other grape strains. Total lipirds were consisted of nutral lipid (87.25%) glycolipid(4.68%) and phospholipid *8.06%) Content of crude proteins was approximatery 11.2% with some variation between strains. Total sugar content was 2.35~5.63$\mu$g/mg with reducing sugar 3.20$\mu$g/mg. Mean saponification value of crude oils was 186.3mg.KOH.oil Antioxidant activity of grape seed oils was better than that of sesame oil resulting in the hi-oils and sesame oil after heat treatment at 18$0^{\circ}C$.

• Journal of Veterinary Clinics
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• v.38 no.4
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• pp.199-203
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• 2021

A 4-year-old Thoroughbred mare was brought to the Korea Racing Authority Equine Hospital with heightened sensitivity to touch of the hindquarter, reluctance to step forward, frequent urination even during training, clitoral winking, tail swinging, tail lifting, and training difficulties due to being in constant heat. The trainer claimed that she was in heat and exhibited reduced performance. Physical and lameness examinations revealed no abnormality. Rectal palpation and transrectal ultrasonography revealed normal reproductive organs and estrus. As she exhibited typical estrous behavior without any other physical conditions, the mare was considered to express undesirable estrous behavior. An intrauterine glass ball was inserted into the mare on ovulation day. However, the estrous behaviors were reduced unsatisfactorily. Additionally, 1 mL of peanut oil was administered on the 10th day after the intrauterine device insertion. The mare returned to training and expressed no undesirable estrous behavior over 30 days after the peanut oil treatment. However, further follow-ups were not conduct as the mare was retired to a farm after a limb injury occurred during training. This is the first report of undesirable estrous behavior in a Thoroughbred mare under the rules of racing in Korea. It is recommended that equine clinicians in Korea consider peanut oil as a therapeutic agent to control mares' estrous behavior-related problems.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.4
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• pp.387-392
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• 2003

The change of crystalline structure and mechanical properties of PET filaments were investigated. Samples were treated by isothermally annealed after elevated heating. Measurements were carried out of density gradient tube for crystallinity and UTM for initial modulus and yield stress. Isothermally heat treatment were carried out $100^{\circ}C$, $120^{\circ}C$, $140^{\circ}C$ for 10min., 30min., 60min, in silicon oil bath. And isothermally heat treatment after elevated heating from $20^{\circ}C$ were carried out $100^{\circ}C$, $120^{\circ}C$, $140^{\circ}C$ for 10min., 30min., 60min., with heating rate of $5^{\circ}C/min$., $10^{\circ}C/min$. From the results of this study, it found the following facts. It was found that the crystallinity, initial modulus and yield stress of samples were increased with increasing of annealed temperature and time. Also crystallinity, initial modulus and yield stress of samples which were isothermally annealed after elevated heating from $20^{\circ}C$ were larger than those of isohtermally annealed samples.