• Korean Journal of Microbiology
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• v.34 no.3
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• pp.162-168
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• 1998

The characteristics of demulsification of petroleum emulsion by Streptomyces sp. 8321 were investigated. Demulsification ability of Streptomyces sp. 8321 appeared to be confined within the spores. Spore surface hydrophobicity was increased with culture age stimulating the demulsification ability. Over $1.1{\times}10^8spores/ml$ completely demulsified kerosene-0.2% Triton X-100 (2:1) emulsion. Among the low viscosity hydrocarbons, hydrocarbons with longer chain such as n-hexadecane and diesel were more rapidly demulsified. However, only 20-30% of the emulsion with high viscosity hydrocarbons was demulsified after 24 hours. Oil-in-water emulsions made by Corexit, Finalsol and BP series surfactants were completely demulsified within one minute. Demulsification rate ($t_{1/2}$) of oil-in-water emulsions made by Corexit 7664, 8667, Triton X-100 and Tween 80 decreased as their concentration increased. In case of water-in-oil emulsion made by Seagreen, $t_{1/2}$ was over 24 hours. Therefore, demulsification ability of Streptomyces sp. 8321 was more effective on oil-in-water emulsions.

• Journal of ILASS-Korea
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• v.19 no.2
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• pp.55-63
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• 2014

Pyrolysis oil (PO), also known as Bio crude oil (BCO), has the potential to displace significant amounts of fuels that are currently derived from petroleum sources. PO has been regarded as an alternative fuel for petroleum fuels to be used in diesel engine. However, the use of PO in a diesel engine requires modifications due to low energy density, high water contents, low acidity, and high viscosity of the PO. One of the easiest way to adopt PO to diesel engine without modifications is emulsification of PO with the fuels that has higher cetane number. However, PO that has high amount of polar chemicals is immiscible with non polar hydrocarbons of diesel. Thus, to stabilize a homogeneous phase of diesel-PO blends, a proper surfactant should be used. In this study, a DI diesel engine operated with diesel and diesel-PO emulsions was experimentally investigated. Performance and gaseous & particle emission characteristics of a diesel engine fuelled by diesel-PO emulsions were examined. Results showed that stable engine operation was possible with the emulsions and engine output power was comparable to diesel operation.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.125-126
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• 2014

습식도금에 사용되는 처리액의 성분농도는 다양한 요인 때문에 변화한다. 안정한 품질로서 처리하기 위하여 성분이나 반응생성물 농도를 분석하고 처리액 농도를 파악하여 유지 관리할 필요가 있다. 도금약품개발에 즈음하여 약품제조사는 가동범위가 넓고 불순물 혼입에 강한 조성개발을 시도했다. 본고에서는 표면처리에 사용되는 전처리용액, 도금액 분석에 사용되는 방법, 조성과 관리에 관하 여 기술하였다.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.1
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• pp.131-140
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• 2012

In this study, using the governing equation for thermohydrodyamic lubrication involving the homogeneous mixture of incompressible fluid derived by based on the principle of continuum mechanics, it is discussed the effects of water within engine oil on the performance of high speed journal bearing of a turbocharger. The governing equations are the general equations being able to be applied on the mixture of Newtonian fluid and non- Newtonian fluid. Here, the fluid viscosity index, n of power-law non-Newtonian fluid is supposed to be 1 for the application of the journal bearing in a turbocharger lubricated with the mixture of two Newtonian fluid, for example, water within engine oil. The results related with the bearing performance are shown that the bearing friction is to decrease and the side leakage and bearing load increase as increasing the water content in an engine oil.

• Tribology and Lubricants
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• v.27 no.4
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• pp.183-192
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• 2011

In this study, using the governing equations for thermohydrodyamic lubrication involving the homogeneous mixture of incompressible fluid derived by based on the principle of continuum mechanics, it is discussed the effects of water dispersed within engine oil on the performance of high speed journal bearing of a turbocharger. The governing equations are the general equations being able to be applied on the mixture of Newtonian fluid and non-Newtonian fluid. Here, the fluid viscosity index, n of power-law non-Newtonian fluid is supposed to be 1 for the application of the journal bearing on a turbocharger lubricated with the mixture of two Newtonian fluids, water dispersed within engine oil. The results related with the bearing performance are showed that the friction force and bearing load capacity decrease as increasing the volume percent of water.

• Tribology and Lubricants
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• v.27 no.2
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• pp.77-87
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• 2011

In this study, using the governing equation for thermohydrodyamic lubrication involving the homogeneous mixture of incompressible fluid derived by based on the principle of continuum mechanics, it is discussed the effects of water within turbine oil on the performance of high speed journal bearing of a steam turbine shipping engine. The governing equation is the general equation being able to be applied on the mixture of Newtonian fluid and non-Newtonian fluid. Here, the fluid viscosity index, n of power-law non-Newtonian fluid is supposed to be 1 for the application of the journal bearing in a steam turbine shipping engine lubricated with the mixture of two Newtonian fluid, for example, water within turbine oil. The results related with the bearing performance are showed.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.255-256
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• 2016

어선의 어업별 밀집 분포도 구축을 통해 어선의 통항흐름을 인지하여, 스크류/추진기 등의 손상과 어망 손괴사고 등을 예방할 수 있다. 아울러, 전국 연안 VTS의 관제구역 설정, 제주연안 돌고래 보호구역 설정, 해상풍력발전 단지 조성과 같은 해상교통안전진단 등의 타당성 입증자료, 허베이스피리트호 사건과 같은 유류유출사고 등과 같은 피해액 산출 추정을 위한 기초 자료로도 활용될 수 있을 것으로 판단된다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.288-289
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• 2012

이동통신, 전자부품의 고속송신에 따라 핵심으로 사용되는 인쇄회로기판(PCB, Printed Circuit Board)의 신뢰성을 향상시키기 위한 주석도금기술과 품질 향상이 요구되고 있다. 오랜 역사를 갖고 있는 습식전자부품 주석도금기술은 과거의 현장에서 기본원리, 도금액분석 등을 이수하는 정도였다. 최근 도금뿌리산업육성과 함께 PCB주석도금 신기술정보를 입수하여 현장품질기술지원이 필요하다. 이에 수시로 업그레이드되고 변화하고 있는 해외신기술동향과 특허정보를 지원하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.290-290
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• 2012

산성Sn도금액은 첨가제에 어떠한 유기화합물을 사용하는가는 도금장치나 석출상태로써 결정할 수 있다. Hothersall과 Bradshaw는 Cresol술폰산을 첨가하여 도금액 안정성 향상을 발견했다. Cresol술폰산은 $Sn^{2+}$의 안정제이며, Gelatine은 분산제기능을 한다. 붕 불화용액은 Sn농도를 높일 수 있고, $2{\sim}12A/dm^2$의 고 전류밀도의 도금이 가능하다. 1937년 Schloetter가 개발하여 미국의 제철회사에서 사용되었다. 본고에서는 최근의 습식주석도금의 특성을 중심으로 기술하였다.

• Journal of Korean Medical classics
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• v.18 no.3 s.30
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• pp.17-26
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• 2005

음양오행설시한의학적기본원리(陰陽五行說是韓醫學的基本原理). 오행포괄목(五行包括木), 화(火), 토(土), 금(金), 수(水), 기상호간구유상생여상극적관계(其相互間具有相生與相克的關係), 인기유불급이보지(因其有不及而補之), 태과이억지적작용(太過而抑之的作用), 고상능유지평형(故常能維持平衡), 인체의차원리(人體依此原理), 역능불급이보지(亦能不及而補之), 태과이억지(太過而抑之). 재차문중주요연구(在此文中主要硏究), 화과성시유수래억제이조절평형적원리(火過盛時由水來抑制而調節平衡的原理). 오행중수배속어신(五行中水配屬於腎), 신주전신지수액(腎主全身之水液). 이신지수액(而腎之水液), 우분화위오종부동형태적오액(又分化爲五種不同形態的五液), 분별배속어오장(分別配屬於五臟). 인차(因此), 연구신수분화위부동형태지오액적과정화분별배속어오장적원리(硏究腎水分化爲不同形態之五液的過程和分別配屬於五臟的原理), 기능설명해제인체중과성적열이유지평형적도리(旣能說明解除人體中過盛的熱而維持平衡的道理).