• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1630-1632
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• 1996

The static charges are generated by streaming electrification phenomena when insulating oil flowing by force for the purpose of cooling at the internal of Ultra-high power transformer. In this thesis, their elimination method was studied. In this paper the effect of Additive on the electric conductivity of Insulating oil is studied. The variation of electric conductivity disappear when Additive is molten in insulating oil, the variation of Additive is not enough to decrease streaming electrification of insulating oil(${\sigma}>10^{-12}$[S/cm]).

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2003년도 학술대회지
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• pp.185-190
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• 2003

Synchronizer ring performance is strictly required in order to extend manual transmission oil drain interval. Zn type additive, which is used as dispersant and anti-wear additive instead of SP additives in manual transmission oil, is applied to improve Synchronizing function and durability. But only Zn type additive is not suitable for high torque transmission because it has not good extreme pressure characteristics. We research on the synchronizer friction and extreme pressure properties in according to change additive types. As a result, it was found that the use of non-active extreme pressure and friction modifier additives has benefit in the improvement of synchronizer friction characteristics and durability.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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• pp.347-352
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• 2000

Before investigating the performance of NA-Q additive oil, we have studied the properties of the commercial reference oil by using an engine dynamometer. Experimemts were conducted for 300 hours with 2,950rpm and 22kw and every 50 hours the used oil was sampled for analyzing its physical and chemical propreties. The reference oil shows stable but slightly increasing viscosities during the experiment. It has good agreements with the change of its TAN and TBN. Friction coefficients and anti-wear characteristics are compared with its ZDTP depletion factor and the diameters of wear scar. The concentrations of metal particles are analyzed with the results of ICP and spectrometer, However it is found that the concentrations by filtration method shows large difference with those by standard method in spectrometer.

• Tribology and Lubricants
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• 제11권5호
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• pp.136-143
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• 1995

The effect of additive chemistry on the serface fatigue of gears was investigated using the FZG gear tester and fluids based on an API GL-5 grade oil. Surface fatigue lives were determined as a function of load and additive chemistry. At 1.52 GPa, the removal of the primary extreme pressure additive (EP) from the fully formulated gear oil decreased the fatigue life of gears slightly (4%), however, the removal of the primary antiwear additive (AW) decreased the fatigue life of gears significantly (83%). At 1.86 GPa, the removal of the EP additive from the fully formulated gear oil decresed the gear fatigue life 27%, however, the removal of the primary AW additive decreased the fatigue life of gears significantly (75%). Micropitting was the dominant surface morphology in the dedendum of gears tested With two oils at load stage: one using the complete additive package, and a second where the EP additive has been removed. However, spalling is the primary failure mode of gears tested without an AW additive independent of whether an EP agent was present. Surface analysis of pinion gears showed the formation of a mixed phosphate/phosphite-oxide layer on the surface of gears tested with fluids containing an AW. Formation of this layer seems to be key to long fatigue life.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.158-161
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• 1996

The static charges are generated by streaming electrification phenomena in insulating oil flowing by force for the purpose of cooling at the internal of Ultra-high power transformer. In this thesis, their elimination method was studied. In this paper the effect of Additive on the electric conductivity of Insulating oil is studied. The variation of electric conductivity disappear when Additive is molten in insulating oil BTA(Benzotriazole) appear more variation of electric conductivity than that of SP-S10(Sorbitan mono-stearate). But the variation is not enough to decrease streaming electrification of insulating oil($\sigma$>10$\^$-12/[S/cm]).

• 해양환경안전학회지
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• 제13권1호
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• pp.39-45
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• 2007

최근 국제 유가의 상승으로 인한 선박 운용비를 절감하기 위하여 중소형 선박에서도 저질연료유의 사용이 검토되고 있는 추세이다. 이 연구에서는 현재 중소형 선박에서 연료유로 사용중인 경유와 중유MF380을 혼합하여 소형선박에 사용이 가능하도록 제조한 혼합연료유인 MF30 연료유에 대하여 그 물리 화학적 특성을 분석하고 정제처리 및 연료유첨가제 효과에 대해 알아보았다. 연구결과 두 가지 전처리 방식인 원심식청정기와 가열 및 균질 방식(M.C.H)의 효과는 다소 미약하였지만, 유동점과 인화점은 다소 낮아졌다. 연료유첨가제로 인한 개질 효과는 뚜렷이 나타나지 않았다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.291-297
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• 2006

최근 국제 유가의 상승으로 인한 선박 운용비를 절감하기 위하여 중소형 선박에서도 저질연료유의 사용이 검토되고 있는 추세이다. 이 연구에서는 현재 중소형 선박에서 연료유로 사용중인 경유와 중유 MF380 을 혼합하여 소형선박에 사용이 가능하도록 제조한 혼합연료유인 MF30 연료유에 대하여 그 물리 화학적 특성을 분석하고 정제처리 및 연료유첨가제 효과에 대해 알아보았다. 연구 결과 두가지 전처리 방식인 원심식청정기와 가열 및 균질 방식 (M.C.H) 의 효과는 다소 미약하였지만, 유동점과 인화점은 다소 낮아졌다. 연료유첨가제로 인한 개질 효과는 뚜렷이 나타나지 않았다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제29회 춘계학술대회
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• pp.189-194
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• 1999

The antiwear performance of several organic phosphates ,such as tricrecylphosphate(TCP), tributylphosphate(TBP), diphenylhydrogenphosphate(DPHP) ,dissolved in polyol ester based oils is studied. These organic phosphates are well known for antiwear additive for lubricating oil that produce reacted surface protective film. These antiwear additives can drastically reduce wear with their concentration increasing, because the amount of additive adsorbed on metal sur(ace increases. But in the higher concentration region, the wear is increased by excessive and corrosive reaction of the metal surface with these additives. That is to say, there is an optimum concentration for minimum wear. The optimum concentration was different with the kinds of base oils and additives. Different polyolesters showed different optimum concentrations of the additive. The order of optimum concentration among the polyolesters was different with different phosphates. The order of the optimum concentration is shown that the effect of the concentration of additives on the antiwear performance. It can be explained by the interaction between additives and base oils using the solubility parameter.

• Tribology and Lubricants
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• 제36권6호
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• pp.342-349
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• 2020

The rapidly increasing threats to the environmental has increased the demand for biodegradable lubricants. Vegetable oils, such as olive, coconut, and sunflower oils, are readily obtainable and are not harmful, unlike synthetic and mineral oils. The tribological characteristics of these oils should be adequately examined for industrial applications. In this study, the lubrication characteristics of olive oil is investigated using a pin-on-disk-type tribometer under 500 gf of normal force, and the examination results are compared and analyzed with those of commercial synthetic lubricants for friction and wear. In addition, stearic acid, which is a type of saturated fatty acid, is mixed with olive oil as an additive to improve its lubrication characteristics. Olive oil with stearic acid additive is thus observed to exhibit the lowest friction coefficient for rotational speeds of 200 to 800 rpm. According to the wear analysis, a minimal amount of wear is observed when no additive is used. Hence, olive oil is able to effectively reduce friction and wear at relatively low speeds. These low friction and wear characteristics of olive oil are attributed to its compatibility with the substrate.

• Carbon letters
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• 제23권
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• pp.48-54
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• 2017

This research considers the effect of added mesophase pitch (MP) as an additive during the pitch synthesis reaction of pyrolyzed fuel oil (PFO). Two effects are generated by adding MP. One is an enhancement of thermal stability due to the high thermal property of the additive; the other is that the volatile compounds that were removed by vaporization of PFO during the thermal reaction can participate in the pitch synthesis reaction ($PFO{\rightarrow}pitch$) more efficiently. The effect differs according to the amount of the additive. When the amount of the additive is less than 7 wt%, the first effect is dominant, whereas the second effect is dominant when the additive amount exceeds 10 wt%.