• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.296-299
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• 2001

Data on the oil spill recovery from the water surface by light floating electromagnetic plants using a new magnetic adsorbent are given. The feasibility scope for further oil recovery from such gathered mixtures(oil + adsorbent), reuse of this magnetic adsorbent and its property reclaiming and recycling were shown. The basic conception of the oil spill recovery and efficiency of this method were set forth.

• International Journal of Precision Engineering and Manufacturing
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• 제8권3호
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• pp.50-53
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• 2007

Improving the reliability or long-term dependability of a system requires a different approach from the previous emphasis on short-term concerns. The purpose of this paper is to present a reliability evaluation method for an oil cooler intended for high-precision machining centers. The oil cooler system in question is a cooling device that minimizes the deformation caused from the heat generated by driving devices. This system is used for machine tools and semiconductor equipment. We predicted the reliability of the system based on the failure rate database and conducted the reliability test using a test-bed to evaluate the life of the oil cooler. The results provided an indication of the reliability of the system in terms of the failure rate and the MTBF of the oil cooler system and its components, as well as a distribution of the failure mode. These results will help increase the reliability of oil cooler systems. The evaluation method can also be used to determine the reliability of other machinery products.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.296-299
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• 2001

Data on the oil spill recovery from the water surface by light floating electromagnetic plants using a new magnetic adsorbent are given. The feasibility scope for further oil recovery from such gathered mixtures(oil+adsorbent), reuse of this magnetic adsorbent and its properly reclaiming and recycling were shown. The basic conception of the oil spill recovery and efficiency of this method were set forth.

• Tribology and Lubricants
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• 제27권4호
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• pp.193-197
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• 2011

Friction behavior of nanoporous anodic aluminum oxide(AAO) film was investigated. A 60 ${\mu}m$ thick AAO film having nanopores of 45 nm diameter with 105 nm interpore-diatance was fabricated by mild anodization process. The AAO film was then saturated with paraffinic oil. Reciprocating ball-on-flat sliding friction tests using 1 mm diameter steel ball as the counterpart were carried out with normal load ranging from 0.1 N to 1 N in an ambient environment. The morphology of worn surfaces were analyzed using scanning electron microscopy. The friction coefficient significantly increased with the increase of load. The boundary lubrication layer of paraffinic oil contributed to the lower friction at relatively low load (0.1 N), but it is less effective at high load (1 N). Plastic deformed layer patches were formed on the worn surface of oil-enriched AAO at relatively low load (0.1 N) without evidence of tribochemical reaction. On the other hand, thick tribolayers were formed on the worn surface of both oil-enriched and as-prepared AAO at relatively high load (1 N) due to tribochemical reaction and material transfer.

• 한국응용과학기술학회지
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• 제28권1호
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• pp.1-5
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• 2011

In this study, We investigated the properites of nano-emulsions containing hydrogenated lecithin prepared by high pressure homogenizer. The size of droplet of emulsions prepared by homogenizer at various rpm (rotation per minute) was not measured due to the unstability of emulsions, however, the size of droplet of nano-emulsions prepared by high pressure homogenizer was around 300 nm and the appearance of emulsions was bluish. The stability of emulsions with various lecithin concentration was tested against time. POV (Peroxide value) of emulsions were plotted against time. POVs of emulsions prepared with an egg lecithin and a soy lecithin were increased with time, however, POV of emulsion with Lecinol S-$10^{(R)}$ was kept constant within 60 hours and at $60^{\circ}C$. In consumer test, the nano-emulsion showed higher affinity regardless of skin type. Both of irritation scores of emulsions were similar.

• 한국응용과학기술학회지
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• 제29권3호
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• pp.486-494
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• 2012

다양한 화장품에 응용을 위하여 제주산 유채오일 추출물을 대상으로 PIT유화시스템을 이용한 나노에멀젼을 제조하였다. 천연 유채오일 추출물은 n-헥산을 용매로 사용하여 추출하였다. 천연유채오일 추출물은 엷은 노란색의 점성을 가진 액체이었고, 수율은 $43{\pm}2.5%$이었다. 산가는 $2.76{\pm}0.5$이었고, 비중은 $0.89{\pm}0.05$ 이었다. 20wt%의 유채오일을 사용한 PIT-Yuche-NE의 입자크기는 50-120nm (평균입자크기: $82{\pm}5.8nm$)이었고, 제타 포텐셜은 -29.5mV 이었다. 이것은 $(PEG)_{5-30}$ 지방산 에테르를 사용하기 때문에 열역학적으로 안정하였다. 특징적인 결과로부터 얻은 몇 개의 결론을 다음과 같이 나열하였다. 첫째, DPPH (1,1-diphenyl-2-picrylhydrazyl radical)방법을 이용한 자유 라디칼 소거력을 측정하였다. PIT-Yuche-NE의 항산화력은 $37.2{\pm}6.7%$이었고, 비교군인 10 mg/mL의 PIT-Toco-NE(토코페롤 20wt% 나노에멀젼)은 $28.8{\pm}6.5%$, 10 mg/mL의 PIT-Nokcha-NE (녹차추출물 20wt% 나노에멀젼)은 $29.6{\pm}7.2%$이었다. 둘째, PIT-Yuche-NE의 콜라겐합성율은 $148{\pm}15.2%$ 이었고, 동일 농도에서 비교군인 PIT-Toco-NE은 $121{\pm}13.5%$, PIT-Nokcha-NE은 $95{\pm}12.7%$이었다. 셋째, 6시간 후, Aramo-TS를 사용한 Yuche-CRM의 피부보습효과는 $47{\pm}3.9%$ (*p-value￡0.05, n=7)이었다. 반면, Toco-CRM은 $30{\pm}5.2%$(*p-value￡0.05, n=7)이었고, Nokcha-CRM은 $35{\pm}4.5%$이었다. 따라서 Yuche-CRM은 다른 두 크림보다 높은 보습효과를 보였다. 최종적으로 본 연구는 화장품 산업 및 제약산업에서도 폭넓게 응용될 것으로 기대한다.

• 소성∙가공
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• 제16권1호
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• pp.20-24
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• 2007

Polypropylene substrate with hair-like nano features(aspect $ratio{\sim}10$) on the surface is fabricated by injection molding process. Pure aluminum plate is anodized to have nano pore array on the surface and used as a stamper for molding nano features, The size and the thickness of the stamper is $30mm{\times}30mm$ and 1mm. The fabricated pore is about 120nm in diameter and 1.5 um deep. For molding of a substrate with nano-hair type of surface features, the stamper is heated up over $150^{\circ}C$ before the filling stage and cooled down below $70^{\circ}C$ after filling to release the molded part. For heating the stamper, stamper itself is used as a heating element by applying electrical power directly to each end of the stamper. The stamper becomes cooled down without circulation of coolant such as water or oil. With this new stamper heating method, nano hairs with aspect ratio of about 10 was successfully injection molded. We also found the heating & cooling process of the stamper is good for releasing of molded nano-hairs.

• 열처리공학회지
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• 제27권2호
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• pp.65-71
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• 2014

SMF9060 material is a Fe-based powder sintered alloy that is used for several automobile components such as Synchronize Hub, oil pump and transmission. These components are required excellent wear resistance and durability. In this study, we have performed a dry wear test at the ambient air and Ar gas conditions in the room temperature, and a lubricant wear test at the room temperature and engine oil temperature of $100^{\circ}C$. The amount of wear volume and coefficient friction are measured by a Profilometer and a Ball on disk type wear tester. The wear volume in Ar gas condition was a little higher than that in the ambient air condition. However the wear volume in the lubricant wear condition was much lower than in the dry wear condition. XRD analysis of the debris in Ar gas condition showed that the oxide film was not formed.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제38차 학술발표대회
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• pp.114-116
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• 2008

Poly(${\varepsilon}$-caprolactone) nanocapsules(nanoPCL) containing phytoncide oil were synthesized by emulsion diffusion method using ethyl acetate as organic solvent. The influence of the degree of hydrolyzation of poly(vinyl acohol) used as an emulsion stabilizer, and the different weight ratio of core material to wall material on the particle size, morphology, and emulsion stability was investigated to design nanocapsules. The encapsulated nanoPCL were characterized by FT-IR spetrometry, Scanning electron microscope, Differential scanning calorimetry, and Thermogravimetry analysis, respectively.

• 한국입자에어로졸학회지
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• 제11권3호
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• pp.77-85
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• 2015

A Belousov-Zhabotinsky reaction in a liquid-liquid system under microwave radiation was observed under non-stirring conditions. To control this non-equilibrium reaction, nano-particle, which is active under microwave irradiation, was added to the solution. Color changes of the solution during the oscillatory reaction were found to be influenced by the irradiation power although the droplet temperature was equal to the temperature of surrounding oil. During the irradiation, the period of oscillation became shorter because the reaction rate was faster. It could also be observed that there is possibility to eliminate oscillatory behaviors of the reaction using higher power of microwave. The possibility of controlling non-linear reaction using microwave was shown since microwave can easily travel through oil phase and reach water phase.