• The Korean Journal of Food And Nutrition
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• v.8 no.2
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• pp.59-69
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• 1995

This study designed to compare the hypolipidemic e(feats of n6 linoleic acid (LA), n3 w-linolenic acid(LL) and n3 eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA) In rats fed high fat (40% Cal) diet. Male Sprague-Dawley rats fed experimental diets for 6 weeks, which were different only in fatty acid composition. The dietary fats were beef tallow (BT) as a source of saturated fatty acid (SFA), corn oil(CO) for n6 LA, perilla oil (PO) for n3 a-LL and fish oil (FO) for n3 EPA+DHA. Plasma total cholesterol (T-chol) level was increased by n6 LA but decreased by n3 LL and n3 EPA+DHA and most effectively reduced by n3 EPA+DHA. Plasma triglyceride(TG ) level was reduced by n6 LA, but lipogenesis in liver was not affected by n6 LA. However, plasma TG level was lowered by n3 LL and EPA+DHA. Both lipogenic enzyme activity and liver TG level were also decreased by n3 PUFA. PO and FO groups were significantly higher in the relative Proportions of C20:5 and C22:6 of plasma and liver and lower in those of C20:4/C20:5 ratio. Overall, the lipid-lowering effect was in the order of n3 EPA+DHA >n3 LL > n6 LA and fish oil and perilla oil rich in n3 PUFA may have important nutritional applications in the prevention and treatment of hyperlipidemia.

• Journal of Nutrition and Health
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• v.26 no.5
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• pp.566-577
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• 1993

The study was to compare the effect of dietary fatty acids on fatty acid profile in tissue and the status of tocopherol and lipid peroxidation, and superoxide dismutase and glutathione peroxidase activities at two fat levels. Male Sprague Dawley rats weighing average 350g(17 weeks) were fed either low fat(LF, 4.3% w/w, 10% kcal) or high fat(HF, 20.8%, w/w, 40% kcal)diet for 6 weeks. The fats used were beef tallow as a source of saturated fatty acid, corn oil for n-6 linoleic acid, perilla oil for n-3 $\alpha$-linolenic acid and fish oil for n-3 eiocosapentatenoic acid(EPA) and n-3 docosahexaenoic acid(DHA). Palsma tocopherol was significantly reduced by fish oil compared to beef tallow at body fat level. However, there was no significant effect on the levels of plasma MDA, RBC MDA and tocopherol, and RBC hempolysis by the type and amount of dietary fat. The peroxidizibility index of fatty acid profile in plasma and liver was increased and liver MDA level was significantly increased by fish oil when dietary fat level was increased. The activities of SOD and GSHPx tended to be increased by perilla oil and fish oil at both fat oil significantly reduced the incorpration of c20:4 and increased the incorporation of c20:5 into liver compared to corn oil. The incorporation of n-3 fatty acids into tissue by perilla oil rich in $\alpha$-linolenic acid was significantly higher tan corn oil and its effect was improved with higher amount of perilla oil in diet by high fat diet. Overall, the lipid peroxidation of tissue could be prevented by tocopherol supplementation when dietary fat level was low in diet. However, at high fat diet, tocopherol supplementation might not be enough to prevent the lipid peroxidation in tissue since the potential for lipid peroxidation was tended to be increased with higher incorporation of higher unsaturated n-3 fatty acids into tissue. Therefore, it could not be recommended to consume large amount of fish oil even with excess amount of tocopherol supplemented to the high fat diet.

• The Journal of the Convergence on Culture Technology
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• v.4 no.3
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• pp.93-98
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• 2018

The article studies macroeconomic effects of the oil shock for Korea, which is a representative emerging economy of Asia and a small open economy. This article analyzed the macroeconomic effects of oil shocks in terms of demand and supply. In the case of Korea, oil price shocks different responds depending on factors of shock. Oil supply shock have led to a decline in industrial activity and interest rate, and oil specific demand shock have shown the greatest increase in interest rate relative to other oil price shocks. In addition, oil demand shock driven by economic activity showed that the comsumer price and the exchange rate are the largest compared to the oil shock caused by other factors. Therefore, policy makers will need to identify the source of the oil shock.

• Journal of Biosystems Engineering
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• v.2 no.1
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• pp.1-6
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• 1977

The dilution of crankcase oil with unburned portions of the fuel during operating is one source of the oil contaminations which will reduce engine life.It has been learned that major causes of oil dilution may be the result of using impure fuels which were mixed with water, dust, and some others, but very little was known about this. This study was conducted to develop a more intimate understanding about oil dilution of the farm kerosene engine while using impure fuel mixed with expecially diesel. Fuels being used in this study were 9 kinds of mixed fuels, kerosene and diesel. Farm kerosenen engine of 10 P.S. was tested at no-load of 1000 and 2000 rpm., such as 1/4, 2/4, 3/4, 4/4, and 11/10 loads for understanding about oil dilution of keresene engine.The result of this study are summarized as follows : 1. The amounts of oil dilution of the engine being tested was increased with increase in the applied loads and the contents of diesel in the mixed fuels when using fuels other than kerosenen and diesel, whereas at $D_100$ fuel the comount of oil dilution decreased in some cases. The lowest value was measured to be 20 cc/hr, at $K_90$ fuel of no-load condition, and the highest value to be 293cc/hr. at $K_{10}$ fuel of 4/4 load condition. 2. When the engine was operated at no-load condition, the amount of oil dilution at 100rpm. was much more than at 2000 rpm. 3. Because the fuel consumption and the oil dilution showed a similar tendency along the applied loads, the excessive fuel consumption of engines was supposed to be one of the important factors affecting oil dilution. 4. The temperature of crankcse oil was varied invesely with oil dilution, but they were not thought to be factors to determine each other variable. 5. The tested engine could be operated with high percentage of diesel mixed fuel from no-load condition to fully loaded condition, but it would be impossible to operate the engine for long hous continuously due to excessive speed fluctuation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.552-561
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• 2018

Biomass, a carbon-neutral resource, is an alternative energy source for exhaustion of fossil fuel and environmental problems. Most of energy production systems using biomass operate with a thermal chemical conversion method. Amongst them, gasification generates syngas and applies to boilers or engines for the production of heat and electricity. However, Tar could be formed during the production of syngas and it is condensed at low temperature which may cause to clog the pipelines and combustion chamber, ultimately resulting in decrease of process efficiency. Thus this work utilized water and oily materials such as soybean oil, waste cooking oil and mineral oil for scrubbing liquid. The removal efficiency of Tar appeared 97%, 70%, 63% and 30% for soybean oil, waste cooking oil, mineral oil and water respectively.

• KSBB Journal
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• v.25 no.3
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• pp.239-243
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• 2010

Six strains of Ralstonia eutropha were grown to investigate characteristics of polyhydroxyalkanoates (PHA) synthesis from vegetable oils or glycerol. Poly(3-hydroxybutyrate) homopolymer was formed using soybean oil, olive oil, or glycerol as carbon source, while poly(3-hydroxybutyrate-co-4-hydroxybutyrate) or poly(3-hydroxybutyrateco-3-hydroxyvalerate) copolymers were synthesized by co-feeding $\gamma$-butyrolactone or pentanoic acid, respectively. Optimum strain was determined as R. eutropha KCTC 2662 in terms of final cell concentration and PHA content. From 20 g/L of soybean oil (optimum substrate), cell concentration and PHA content at 72 h ranged 1.7~9.2 g/L and 70~92 wt%, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.2
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• pp.95-101
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• 1989

For the utilization of polyunsaturated fatty acids in sardine (Sardinops melanosticta) oil, mainly as a source for dietary supplement of eicosapentaenoic acid(EPA) and docosahe-xaenoic acid(DHA), the effects of refining and storage, conditions, and addition of stabili-zing agents on the storage stability of EPA condensed and refined sardine oil were tested. Refined, sardine oil deacidified, decolored, and deodorized, was more stable to autoxidation than crude or partially purified oils such as deacidified or/and decolored. The refined sardine oil must be kept at $5^{\circ}C$ or lower temperture for longer than two month storage. The addition of $0.018\%\;\alpha-tocopherol$ or BHT could enhance the stability to autoxidation, and EDTA or citric acid was useful as synergist. Especially the addition of $0.02\%$ citric acid to the oil still hot after deodorizing process ($125^{\circ}C$) was of benefit to stabilize the refined oil.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.2
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• pp.114-119
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• 2016

This paper dealt with the propagation characteristics of acoustic signal in insulation oil for the purpose of improving the reliability of AE (acoustic emission) method used for condition monitoring of oil-immersed transformers. A discharge source was placed in insulation oil and AE sensors ($f_c$ :140 kHz) were attached on the oil tank to study the changes of velocity and propagation path with the depth and distance. The average velocity was 1,436 m/s and the velocity decreased with the increase of depth from the oil surface to 430 mm. The propagation paths were classified into three sections by the shortest reflection path of the detected signal. The minimum distinguishable distance in each section was 70 mm. It was also verified that PD (partial discharge) with a magnitude over than 500 pC can be detected by the AE sensors.

• Journal of Life Science
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• v.14 no.5
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• pp.834-839
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• 2004

To improve and oil degrading activity, the lipase gene from Pseudomonase sp. was transformed into Klebsiella sp. KCL-l, an oil degrading bacterium. The selected trasformant was named as a KCL-1/pET-Lip. The surface tension of culture broth of KCL-1/pET-Lip was decreased to 33 dyne/cm from 55 dyne/cm using 4% (v/v) soybean oil as sole carbon source. The surface tension were 44 and 37.5 dyne/cm, to 2% (w/v) glucose and 4% (v/v) kerosene medium, respectively. The emulsification activity of the biosurfactant solution containing lipase of KCL-l/pET-Lip improved better than wild type KCL-l. The soybean oil was most efficient carbon source and substrate for surface activity and emulsification activity of KCL-1/pET-Lip. The expression of lipase was confirmed by SDS-PAGE.

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.163-170
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• 2001

The effect of perilla oil added in diet on the biochemical properties of cultured sweet smelt, Plecoglossus altivelis, was investigated. The cultured fish were fed two different diets for 8 weeks; a control diet was a commercial diet, which was low in the content of docosa­hexaenoic acid (DHA, 22: 6n-3) and eicosapentaenoic acid (EPA, 20: 5n-3) less than approximately $2\%$ (CO group) and an experimental diet (PO group) was added perilla oil as a lipid source in the diet of the CO group. The PO group was superior in growth rate and feed efficiency compared with CO group. This trend showed markedly in female of both groups. The fatty acid composition in the muscle of PO group was closely related with those of the diet, while those of CO group were not. For plasma components, total cholesterol (CHOU of PO group was higher than that of CO group. Thiobarbituric acid-reactive substances (TBARS), hydroxyl (OH) radical levels and superoxide dismutase (SOD) activity of plasma were higher in PO group than CO group. The intensity of watermelon-like or cucumber-like aroma was much stronger in PO group with higher level of TBARS and OH radical in plasma compared CO group. Survival rate was also high in PO group with high levels of phagocytic rate, CHOL and SOD activity. These results suggest that perilla oil might be usefulness as a lipid source of the cultured sweet smelt diet, in which result in high quality of the cultured fish.