• 대한화학회지
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• 제33권5호
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• pp.459-467
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• 1989

계면활성제가 수용액 중에 용해되면 용액내에서 micelle이라는 응집체를 형성하며, micelle은 그 내부에 oil를 용해시켜 swollen micelle을 형성하게 된다. 실제로 물-oil-계면활성계의 상평형도상에서 micelle과 swollen micelle은 동일영역에 존재하게 되나 일반적으로 micelle과 swollen micelle의 형성에 관해서는 서로 다른 관점으로 취급되어 왔다. 본 연구에서는 이러한 계면활성제 응집체의 형성에 관한 일관된 열역학적 모델을 제시하고자 한다. 모든 경우에 저농도 영역에서 이상용액 이론을 적용하였으며, micelle 형성에너지는 소수성 작용에너지와 계면에서의 표면에너지의 합으로 표시하였다. 이론식으로부터 임계마이셀농도, 평균응집분자수, 용해비 등을 예측하였으며 실험관측치와 비교하였다.

• 한국건축시공학회지
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• 제10권3호
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• pp.57-64
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• 2010

본 연구는 알루미늄 거푸집 표면코팅재가 콘크리트 표면품질에 미치는 영향에 대하여 분석한 것이다. 콘크리트 표면형상에 미치는 알루미늄 거푸집 표면코팅재 변화의 영향에 따른 콘크리트 표면의 육안관찰시 전반적으로 전용횟수가 증가함에 따라 표면품질은 저하하는 것으로 나타났고, 치장합판(Plywood이하: PW)이 우수한 표면품질을 나타내었다. 에폭시(Epoxy :이하 EP) 수지의 경우는 박리제를 도포하였을 시 표면품질이 우수한 것으로 나타났다. 박리제 도포여부 및 전용횟수에 따른 콘크리트의 표면조도는 전용횟수가 증가함에 따라 가장 높은 표면조도 값을 나타내어 평활성이 불량한 것으로 나타났지만, EP와 PW의 표면조도 값은 가장 우수한 것으로 나타났다. 다만 EP의 경우는 박리제를 도포할 경우 표면조도 값이 낮게 나타났다. 박리제 도포여부 및 전용횟수에 따른 콘크리트의 공극갯수는 전반적으로 박리제를 도포할시 저감하는 것으로 나타났다.

• 미생물학회지
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• 제39권2호
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• pp.102-107
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• 2003

유류오염 토양으로부터 디젤에 대한 분해능이 있는 균주를 순수분리하였고, 이들 분리 균주의 액체 배양을통하여 균체 생육과 유화활성이 우수한 균주를 최종적으로 선별하였다. 생리,생화학적 특성 및 165 rDNA 염기서열 분석을 실시한 결과, Pseudomonas sp.로 분류 되었으며, Pseudomonas sp. GENECO 1으로 명명하였다. Bioscreen C를 이용하여 디젤 분해를 위한 배양 조건을 조사한 결과 최적 배양온도는 $30^{\circ}C$, 초기 pH는 7.0로 나타났다. Gas chromatography를 이용한 배양 시간별 잔류 디젤 성분분석 결과 96시간 이내에 1.0%의 디젤을 95%이상 분해하였다.

• Tribology and Lubricants
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• 제31권3호
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• pp.86-94
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• 2015

We perform lacquer formation experiments with various combinations of marine fuel oils and lubricant oils. We also investigate the influences of base number (BN) in lubricant oil and sulfur content in fuel oil. A dissolution test with 10% dilute sulfuric acid and pull-off force test are accomplished to distinguish whether the residual layers are lacquering or not. The lacquering layers are dissolved by dilute sulfuric acid and have a strong pull-off force. Moreover, the calcium content detected in the residual layers is compared by energy dispersive x-ray spectroscopy (EDS). More calcium is detected in the lacquer layers than in other residual layers. Distillate fuels containing low sulfur levels are more prone to lacquering when mixed with lubricant oil with a high BN. On the other hand, residual fuels with a high sulfur content do not form lacquer. We investigate the effect of mixture volume ratio. The mixture with higher fuel oil content is more prone to generate lacquer. These experiments indicate that a lubricant with an appropriate BN should be used to prevent lacquer forming on the surfaces such as cylinder liners depending on the sulfur content of fuel oil.

• Journal of Biosystems Engineering
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• 제25권6호
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• pp.481-488
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• 2000

This study was initiated in order to find alternative fuel substituting for light oil the most common fuel for heating greenhouse. The tire oil used in this research was produced by pyrolysis process, one of the final products besides steel string and carbon black in which waste tires as a form of chopped pieces broken by shredding machine are heated up to 200~30$0^{\circ}C$ with maximum restraining of oxygen supply. In order to justify light oil equivalent qualities in tire oil combustion characteristics were defined in the way of comparing kinetic viscosities in the wide range of temperature flame sizes and exhaust gas components in the various combustion conditions. We found that kinetic viscosity of tire oil was lower than light oil by 1 to 2 cSt in the temperature range showing better flowing mobility in the fuel line of the burner and no significant difference in flame size between the two oils in the all combustion treatments. However much more NO and SO$_2$ were detected from the exhaust gases of tire oil than light oil combustions. In fact tire oil contains more nitrogen and total sulfur, by 25 times and 40 times respectively than light oil according to the composition analysis. Tolerable limit for SO$_2$discharge amount defined by the national air pollution standards is under 540ppm so tire oil combustion satisfies the requirement though. It is desirable if sulfur and nitrogen filtering process shall be added in the tire oil production line. Except the exhaust gas components all greenhouse heating qualities of tire oil including hot air temperature are very identical to those of light oil.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.578-583
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• 1997

Abstract-Crosshead bearing in two-stroke marine diesel engine is operated under quite severe condition since the load on the bearing is sybject to the loading in a unidirectional and the sliding speed is very slow and oscillatory. So it is very difficult to form oil film and maintain the load. In this paper, two types of bearing are compared. One has large sized oil pocket and the seleted as multi-small oil grooves. Bearing clearance, oil inlet oressure and bearing types are selected as analysis parameters. Loci of journal center are presented to compare several cases. It is found that bearing clearance and shape affect to minimum film thickness.

• 대한화장품학회지
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• 제19권1호
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• pp.31-56
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• 1993

GC와 GC-MSD와 관능시험을 이용하여 Gardinia Jasmoniodes Ellis로 부터 제조한 Gardinia Absolute Oil의 특징적인 방향성분을 확인하였다. GC 분석 방법은 극성 비극성의 column인 Carbowax 20M과 SPB-1을 동시에 장착한 Double Column System을 이용하였으며 GC Workstation에 의한 자동적인 Retention Indexs Match System을 적용하여 분석된 data를 확인하였다. 시험적 판단 성분 9개를 포함하여 전부 51개의 성분을 확인하였다. 주요성분으로 Linalool, 여러 형태의 Farnesene, Jasmin lactone, Gamma undecalactone 그리고 Cis-3-hexene 유도체들이 있다.

• East Asian Economic Review
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• 제16권4호
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• pp.395-410
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• 2012

For historical and political reasons, South Korea (hereafter Korea), Japan and China have not achieved much progress in regional energy cooperation for decades. However, the rising importance of Northeast Asia (NEA) in the world energy sphere, especially in the global oil market, is providing an opportunity to create an integrated oil market in the region. This study suggests the Northeast Asian Energy Corridor (NEAEC) Initiative as an effective conduit for raising the possibility of the Northeast Asian oil hub project. The NEAEC Initiative combines the model of Europe's Amsterdam-Rotterdam-Antwerp (ARA) with Singapore's AsiaClear as a form of financial collaboration. The study suggests that an electronically integrated Over-the-Counter (OTC) market clearing mechanism accompanied by other key financial instruments among Korea, Japan and China can be an effective means for promoting financial collaboration in the region.

• 한국전기전자재료학회논문지
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• 제37권3호
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• pp.280-285
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• 2024

In this paper, the electrical properties of liquid insulating oil were analyzed by changing the ambient temperature change at 10℃ in-tervals from 0℃ to 30℃ through an insulation breakdown experiment in order to analyze the insulation performance of liquid in-sulating oil that varies according to temperature changes. As a result, it was confirmed through experiments that the lower the am-bient temperature, the higher the insulation breakdown voltage, depending on both the electrode shape and the electrode interval, and it was determined that the lower the ambient temperature, the higher the insulation performance of the liquid insulating oil.

• 대한가정학회지
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• 제28권2호
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• pp.31-36
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• 1990

This studies were conducted to find out the possibility of utilizing red pepper seed as resources of food fats, the research method was designed to make a comparison between crude and refined oil, and the results of the studies are as follows : The red pepper seed contained 28% of crude fat and 21% of crude protein. The main fatty acids of red pepper seed oil were linoleic acid(72.10~72.31%), palmitic acid(12.81~13.28%) and oleic acid(9.47~10.48%). The linolenic acid content was so small that is will not influence the autoxidation of the red pepper seed oil. The major triglyceride type of crude and refined oil of red pepper seeds were C52 and C54. The other types were found in a small quantity. The sterol composition of crude oil was $\beta$-sitosterol, campasterol, stigmasteral and brassicasterol,in the quantity order. after refining, brassicasterol was not detected, and the content was decreased by one six and one eight. The toropherol composition of crude and refined oil, tocopherol analog was composed of three kinds $\alpha$-, ${\gamma}$-, $\delta$-, but no $\beta$-form. the quantity of ${\gamma}$-, $\alpha$- and $\delta$-tocopherol were 162.91, 83.72, 43.98mg% respectively. The Quantity of and capsaicin in crude oil was 1,296 ppm, and it was reduced consicerably by refining and removed completely after the process of redeodorization.