• Journal of Nutrition and Health
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• 제1권1호
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• pp.19-25
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• 1968

In order to study the effect of source and level of the commonly used dietary fats on growth and metabolism of rats fed on low protein diet (rice diet) the weaning white rats were fed on various different experimental diets (see tables 1 and 2) during 11 weeks. The observations were made as follows : 1. Growth: (see table 3 and figures 1-9) In all dietary fats, among the 3 levels, 5% fat level is the best. Especially, the perilla oil group was remarkably good. 10% and 20% fat levels impaired the growth, consequently the growth rates of both 10% and 20% fat level groups were worse than those of Basal group (no fat added). However, 10% and 20% fat levels did not impaired the growth of VII group (10% soy flour added) In 5% fat level, the growth was good in sequence of perilla oil, tallow, sesame oil, soy oil and lard. 2. Feed consumption: (see table 3) In 20% fat level, the feed consumption was lowered. Generally, the feed consumption rate was proportional to the growth rate. In feed efficiency, 5% fat level was the best. 3. Liver weight: (see table 4) In liver weight per 100 G body weight, 20% fat level was the largest. This may be due to the poor body growth and liver fat accumulation. 4. Liver nitrogen: (see table 4) Generally, lower fat level groups showed liver nitrogen. Liver nitrogen is low in the groups of 20% fat level. 5. Liver fat: (see table 4) Generally, higher fat level groups showed higher liver fat. 6. Serum cholesterol: (see table 5) Generally, higher fat level groups showed higher serum cholesterol. Lard, sesame oil, and tallow groups showed higher level and soy oil and perilla oil groups showed lower level. Especially, perilla oil group showed remarkably lower level and VII group (10% soy flour added) showed lower level than VI group (same fat but no soy flour added).

• 동력기계공학회지
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• 제13권2호
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• pp.5-10
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• 2009

In recently, studies concerned to the diesel engine uses a natural gas as a fuel oil whose infra has been built already was approached to PCCI or HCCI with keeping a high thermal efficiency and reducing NOx and PM have been researching actively in normally single cylinder. An ignition source is required to bum the natural gas by a spark plug in gasoline engines, due to a higher auto-ignition temperature of natural gas. Then gas oil and DME were introduced as the ignition source. In this study as basic data for practical use of natural gas PCCI and HCCI engines, combustion characteristics and emission characteristics on 4-cylinders natural gas PCCI and HCCI engines with gas oil and DME as ignition sources were analyzed and the engine load range that is main object for practical use of PCCI and HCCI engines was made clearly by empirical experiment.

• 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.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권8호
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• pp.343-349
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• 2005

The gas in oil analysis of transformer is the most widely used technology for diagnosis of transformer in the world. It has brought excellent results to prevention of transformer failure. The criteria for maintenance and judgement, however, is still required continuous supplement to improve the accuracy of the diagnosis on the basis of accumulated data of gas analysis and investigations in the transformer In this study, the relationship between the detection rate of the defects and the source of troubles are analyzed according to the investigation in the transformer, which was conducted by KEPCO in 2004. As a result, the validity of the criteria being used at present was examined thoroughly.

• Fisheries and Aquatic Sciences
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• 제18권4호
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• pp.359-365
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• 2015

We investigated the effects of dietary lipid sources on growth and fatty acid composition of juvenile Chinese longsnout catfish. Triplicate groups of fish (initial average weight, 3.8 g) were fed four diets containing either fish oil (FO), soybean oil (SO), linseed oil (LO) and lauric acid (LA) for 10 weeks. There were no differences among the groups in body weight, feed intake, feed efficiency, protein efficiency ratio, and body proximate composition of fish fed the diets containing different lipid sources (P > 0.05) during the study. However, fatty acids compositions of the whole body were influenced by dietary lipid source. Fish fed the SO diet had high concentration of linoleic acid, whereas those of fish fed the LO diet were rich in linolenic acid and arachidonic acid. Fish fed the FO diet had significantly (P < 0.05) higher levels of monounsaturated fatty acids such as 18:1n-9 and 20:1n-9 than those of fish fed the SO and LO diets. Eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) composition of body were not influenced by dietary lipid source. The results suggest that each of FO, SO, LO or LA can be used as a lipid source in the diets of Chinese longsnout catfish without any negative effects on growth and feed utilization and these data demonstrate the potential impact which dietary fat composition can change the body fatty acid profile.

• Journal of Microbiology and Biotechnology
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• 제22권3호
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• pp.371-377
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• 2012

The present study describes medium-chain-length polyhydroxyalkanoates (mcl-PHAs) production by the Pseudomonas Gl01 strain isolated from mixed microbial communities utilized for PHAs synthesis. A two-step fed-batch fermentation was conducted with glucose and waste rapeseed oil as the main carbon source for obtaining cell growth and mcl-PHAs accumulation, respectively. The results show that the Pseudomonas Gl01 strain is capable of growing and accumulating mcl-PHAs using a waste oily carbon source. The biomass value reached 3.0 g/l of CDW with 20% of PHAs content within 48 h of cultivation. The polymer was purified from lyophilized cells and analyzed by gas chromatography (GC). The results revealed that the monomeric composition of the obtained polyesters depended on the available substrate. When glucose was used in the growth phase, 3-hydroxyundecanoate and 3-hydroxydodecanoate were found in the polymer composition, whereas in the PHAs-accumulating stage, the Pseudomonas Gl01 strain synthesized mcl-PHAs consisting mainly of 3-hydroxyoctanoate and 3-hydroxydecanoate. The transcriptional analysis using reverse-transcription real-time PCR reaction revealed that the phaC1 gene could be transcribed simultaneously to the phaZ gene.

• 대한환경공학회지
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• 제29권8호
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• pp.950-955
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• 2007

본 연구에서 개발한 시스템은 기존에 사용되던 유수분리기를 유류가 혼입되어 발생하는 도로, 교량 등의 도시 불투수면 비점 오염저감장치로 업그레이드한 것으로서 유적입자가 coalescence 원리에 의하여 고밀도 고분자 폴리에틸렌 소재를 사용하여 제작된 메디아의 표면과 공간 사이를 타고 이동하면서 합체되어 유적의 크기가 증가한 후 부상하여 제거되는 기전과 SS 성분의 고형물이 침전에 의해 제거되는 원리를 이용한 도시 비점오염저감시설이다. 따라서 본 연구에서는 coalescence 기전을 통해 유수분리가 일어나는 나선형 고분자 여재의 유수분리 특성을 image analysis를 통해 규명하였으며 또한 도로노면 먼지와 폐엔진오일을 이용하여 비점오염원 저감시설에 유입되는 폐수를 모사하여 비점오염원 저감시설의 유수분리 성능을 실험하였다. 연구에 사용된 여재는 부정형의 투명한 나선형 구조를 갖고 있으며, SEM 사진 및 BET 측정 결과 매끄러운 표면 특성을 나타내고 있다. 직접 측정 방법으로 여재의 표면적을 측정한 결과, 여재 1립당 표면적은 1,428 $mm^2$으로 나타났으며, 단위당 중량은 45.3 $kg/m^3$으로 조사되었다. 또한 폐수 내 기름 입자의 액적크기를 현미경으로 촬영하여 이미지 분석을 수행한 결과, 메디아를 통한 폐수내 기름성분의 제거가 coalescence에 의해 일어나고 있음을 증명하였다. 마지막으로 나선형 부유 메디아를 적용한 비점오염저감시설의 성능평가 결과, 유량에 따라서 부유성 고형물은 $86.6\sim95.2%$, $COD_{Cr}$, $87.3\sim95.4%$, n-Hexane 추출물 $71.8\sim94.8%$의 제거효율을 나타내어 본 장치의 처리성능은 기존의 비점오염원 저감시설의 처리대상물질인 유기물과 부유물질 뿐만 아니라 유류의 제거에도 효과적인 것으로 평가되었다.

• Journal of Advanced Marine Engineering and Technology
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• 제25권2호
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• pp.311-320
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• 2001

Since 1998 for protection of marine pollution, all ships must have oil filtering equipment and 15ppm bilge alarms which satisfy Requirements of MARPOL 73/78. Oily-water separator used in machinery area of ships usually consists of two parts; one is filtering equipment and the other is oil content meter(OCM). This study presents optical characteristics of bilge were acquired form oil content sensing module. The oil content sensing module consists of IR-LED light source, photo-diode light receivers, and a glass tube for bilge water sample. The experiment with the bilge water demonstrates various valuable optical properties. These optical properties suggest notes and guides to make the low-cost, easy operation and good performance commercial type OCM that satisfy the requirements of MARPOL 73/78.

• Applied Biological Chemistry
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• 제27권
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• pp.80-87
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• 1984

Although traditional Korean diet consists of Very little fats and oils, the increase of their consumption, especially vegetable oil, has been truly remarkable in recent years and this increase is attributed to the improvement of their dietary habit and the development of Korean food industry. On the other hand, domestic production of the edible vegetable oil did not increase at all. Naturally, foreign exchange (over a several hundred million U.S. dollars) is annually used in importing oil seed and/or oil per se. Under these circumstances, it is of utmost importance to maximize the domestic production of edible vegetable oil, although its complete self-sufficiency cannot be achieved. In this seminar, intake of fats and oils by Korean people, status and outlook of the domestic production and consumption of fats and oils will be discussed, with. emphasis on the utilization of agricultural by products and waste as a source of fats and oil.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1275-1279
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• 2004

Citron peel oil was extracted from citron (Citrus funas) fruit by steam distillation, and was used as starting material for microbial conversion to synthesize attractive flavor compounds by using Enterobacter agglomerans 6L. E. agglomerans was isolated from citron peel and was able to metabolize the citron peel oil and grew well ($A_{600}:\;3.0$) on the citron peel oil as the sole carbon source. Multiple terpene metabolites were produced by E. agglomerans 6L on M9 salt media with citron oil vapor. The identified bioconversion products from the citron peel oil included trans-2-decenal, octanol, $\delta$­valerolactone, $\gamma$-valerolactone, cryptone, hydroxycitronellol, cuminol, and $\gamma$-dodecalactone.