• 전기학회논문지
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• 제65권10호
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• pp.1688-1693
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• 2016

In this study shall investigate the influence upon the electrical property of transformer oil due to the heat among accelerated heat degradation experiment for a constant hour in the typical insulation oils of mineral base oil, silicon base oil and vegetable oil. In addition, the electric insulation performance of insulation materials in transformer shall be evaluated through the electric property analysis according to the heat degradation of epoxy insulation material, which has been used for electric facilities such as a molded transformer.

• Journal of Mechanical Science and Technology
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• 제18권4호
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• pp.709-717
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• 2004

Biodiesel has great potential as an alternative fuel for diesel engines that would reduce air pollution. It is a domestically produced, renewable fuel that can be manufactured from fresh or used vegetable oils, or from animal fats. In this study, a biodiesel fuel derived from rice bran oil was tested as an alternative fuel for agricultural diesel engines. The emissions were characterized for both neat and blended biodiesel fuels, and for conventional diesel fuel. Since this biodiesel fuel contained 11 % oxygen, it strongly influenced the combustion process. The use of biodiesel fuel resulted in lower carbon monoxide, carbon dioxide, and smoke emissions, without any increase in nitrous oxide emissions. The study demonstrated that biodiesel fuel could be effectively used as a renewable and environmentally innocuous fuel for agricultural diesel engines.

• Journal of Dairy Science and Biotechnology
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• 제27권2호
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• pp.25-36
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• 2009

Trans fatty acids (TFAs), especially elaidic acid, formed during partial hydrogenation of vegetable oils have been shown to increase LDL-cholesterol (LDL-C) and decrease HDL-cholesterol (HDL-C), thereby increasing the LDL-C/HDL-C ratio and elevating the risk of cardiovascular disease. However, studies on the health effects of ruminant TFAs have suggested that these TFAs, which are primarily vaccenic acids, have no or inverse association with coronary heart disease. Thus, dietary recommendations or legislation for TFAs should consider the differences in the physiological effects of TFAs derived from various food sources. This present review recapitulates the progress in TFA research by analyzing recent epidemiological studies or intervention studies and comparing the cardiovascular health effects of industrially produced TFA and ruminant TFA.

• 한국응용과학기술학회지
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• 제20권3호
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• pp.251-258
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• 2003

Biodiesel as methyl esters derived from vegetable oils has considerable advantages in terms of environmental protetion. In the present work, methyl esters were produced from soybean oil by lipase-catalyzed transesterification. To reduce inactivation of commercial immobilized lipases emulsified two-step process was developed using the stepwise addition of methanol with 4:1 molar ratio at 4h intervals. Also with immobilized lipase from Candida antarctica(Novozym 435) high conversion of 98.5 percent was possible at $45^{\circ}C$ of reaction temperature with 4:1 of methanol-to-oil molar ratio and 1%(v/v) methyl glucoside oleic polyester as an emulsifier in the presence of cosolvent.

• Journal of Microbiology and Biotechnology
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• 제21권8호
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• pp.858-860
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• 2011

Production of biosurfactant can be substantially increased by the addition of precursors like vegetable oils, petroleum products, and other water-insoluble substances. Pseudomonas Ptm+ strain produces biosurfactant in the presence of hexachlorocyclohexane (HCH), which specifically emulsifies HCH, a recalcitrant organochlorine pesticide. Addition of previously produced crude biosurfactant by the same organism as a precursor instead of HCH increased production of biosurfactants with a decrease in the total fermentation time from 32 to 24 h. The main objective of this paper was to find alternatives for HCH as an inducer.

• KSBB Journal
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• 제14권6호
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• pp.747-753
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• 1999

Microbial surfactants are more effective and environmentally friendly than many synthetic surfactants. Sophorolipid, a glycolipid type microbial surfactant, is produced from C. bombiocola. Cultivation techniques to increase the productivity have been developed using various carbon sources and reactor setup, reaching its concentration upto 100-300 g/L. Due to its high productivity and non-toxicity, sophorolipid became one of the most promising alternative to synthetic surfactants. Fermentative production of sophorolipid depends primarily on the carbon sources, such as glucose and vegetable oils, and nitrogen sources. Chemical modification of the sophorolipid produces various derivative with different physical properties including hydrophile-liphophilie balance(HLB), emulsion formation, surface tension and dispersing ability. Commercial potentials of sophorolipid in the cosmetic, health care and environment clean-up industries have been discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.80-80
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• 2010

본 논문에서는 현재 사용되는 변압기의 절연유인 광유와 새롭게 대두되고 있는 식물유의 신유 상태일 때, 온도와 유동대전방지제(Benzotriazole)에 따른 대전경향을 비교, 분석함으로써 변화되는 조건이 절연유에 미치는 영향에 관해 연구하였다. 유동대전현상을 해석하기 용이한 직렬식 대전장치를 설계, 제작하여 실험한 결과 온도의 변화에서는 광유, 식물유 모두 60[$^{\circ}C$] 부근에서 최대치를 발생하였고 유동대전방지제의 첨가에 따라 유동대전은 광유, 식물유 모두 비슷한 경향으로 변화하였다.

• 한국응용과학기술학회지
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• 제29권1호
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• pp.81-87
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• 2012

The biodiesel production characteristics in a pulsed-corona plasma reactor has been investigated through parametric tests. Transesterification of rapeseed oil together with camelina oil was done with the change of such variables as voltage of power, molar ratio, KOH catalyst and temperature. The energetic electrons emitted from pulsed-corona plasma has contributed to the enhancement of yield on rapeseed oil in short time (15 min). The higher yield on camelina oil was observed in 5 min. The optimal parameters were shown as the voltage of 23 kV, the molar ratio of 5/1, the content of KOH catalyst of 0.6 wt% and the temperature of $28^{\circ}C$ under the rotating rate of spark gap of 900 rpm.

• Journal of Nutrition and Health
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• 제19권5호
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• pp.289-295
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• 1986

Seven day's menus consisting of the Korean traditional dietary patterns were prepared according to the Korean nutrition allowances per capital of whole population. After cooking foods one day's meal was collected, homogenized for one week. Nutrients in each day's meal were analysed. The results of this analysis are as follows ; Lipids contents were about 23% higher than the data obtained nationwide nutrition survey conducted in 1984. This suggests the increasing tendency of the fat the oil consumption . PUFA ratio in lipid was 35%, that the customary Korean cooking include high confirmiry amount of vegetable oils. Daily tocopherol intake was 8.3mg . This results is believed to as one reference to set up Korean R.D.A for tocopherol.

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.185-190
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• 1996

Some microorganisms including yeasts produce surface tension-decreasing biosurfactants. The strain G-1, the best producer of biosurfatants was isolated from the soil and identified as Rhodotorula sp., which was not discribed any report. The Rhodotorula sp. G-1 produced biosurfactant from vegetable oils, but failed to produce it from n-alkane or carbohydrate. Yeast extract was found to be more effective for the biosurfactant production as nitrogen source than any other inorganic nitrogen source. The composion of the optimal medium contained the following conponents: soybean oil 4%, glucose 2%, yeast extract 0.5%, KH$^{2}$PO$^{4}$ 0.1%, K$^{2}$HP0$^{4}$ 0.l%, MgSO$^{4}$ 5%, CaCl$^{2}$ 0.01%, NaCl 0.01%, pH 6.0. The surface tension activity was increased to 14% when, at first, the culture broth was fermented with only soybean oil as carbon sourse, and after 90 hours, feeded glucose, than that Of glucose and soybean oil added to it simultaneously. The maxium yield of the biosurfactant was about 15 g/l by after 90 hours, the feeding method of glucose.