• Resources Recycling
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• v.19 no.5
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• pp.44-49
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• 2010

SiC powders have been recovered from silicon-containing waste slurry by carbothermal reduction method with carbon black. Large amount of silicon-containing waste slurry is generated from Solar Cell industry. In an environmental and economic point of view, retrieve of the valuable natural resource from the silicon waste is important. In this study, SiC powder recovered by the reaction ball-milled silicon powder from waste and carbon black at $1350^{\circ}C$ for 3h under vacuum condition. Physical properties of samples have been characterized using SEM, XRD, Particle size analyzer and FT-IR spectroscopy.

• 베이커리
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• no.4 s.369
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• pp.94-97
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• 1999

• Proceedings of the Korean Vacuum Society Conference
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• 2006.02a
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• pp.234-234
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• 2006

• Journal of the Korea Institute of Military Science and Technology
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• v.2 no.2
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• pp.234-241
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• 1999

본 논문에서는 얇은 직사각형 단면 형상을 가지는 세 가지 서로 다른 유동로 안에서 움직이는 공기버블의 변형 거동에 대한 실험을 수행하였다. 압력 차이로 유체는 유동되며, 유동장을 따라서 변형하는 버블의 정상상태 모양을 관찰하였다. 벽면효과를 알아보기 위해 세 종류의 얇은 사각단면을 사용하였으며, 두 가지 종류의 작동 유체, 버블의 초기 크기, 작동 유체의 유량 등을 변화시켰을 때 이에 대한 공기 버블의 변형을 체계적으로 관찰하고 이들의 관계를 고찰하였다. 실험데이타를 정량화하여 캐필러리 수에 대한 버블의 무차원 속도비와의 관계를 상세하게 고찰하였다. 글리세린의 경우는 항상 버블 선단부의 곡률이 후단의 곡률보다 더 작게 나타났으며 실리콘 오일의 경우와 반대 경향이 관찰되었다. 두 경우 모두 캐필러리 수에 대한 속도비와 세장비 값은 1 보다 큰 값을 가졌다. 실리콘 오일의 경우는 주어진 Ca 수에 대하여 속도비가 글리세린의 경우보다 더 크게 나왔으며 버블 크기에 따른 속도비 분산도가 더 조밀하게 나타났다. 사각 단면 폭이 감소할수록 벽면 효과는 증대되었으며 같은 폭에 대해서는 버블 변형이 축소관의 경우가 가장 크게 나타났다.

• Digital Contents
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• no.2 s.117
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• pp.36-38
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• 2003

"MBC 성공시대라는 프로그램에서 섭외에 들어왔었다. 해외 진출에 두려움을 갖던 5년 전 과감하게 실리콘밸리에 진출했기 때문이다. 5년의 시간이 흐른 지금, 결과만 놓고 보면 성공했다고 자신할 수 없다. 하지만 성공으로 가는 길이라고는 말할 수 있다." 1994년 PC통신을 이용한 텍스트 기반의 온라인게임 '단군의 땅'을 히트시킨 마리텔레콤의 장인경 대표. 97년 국내 시장을 뒤로하고 실리콘밸리에 진출해 주목받은 그녀가 한국에 '컴백'했다. 오는 4월 미국에서 350만명의 회원을 확보한 게임 '아크스페이스'와 '아크메이지'를 국내에서 선보인다. 장인경(50) 대표를 만나 국내 서비스 전략과 해외진출 업체들에게 전하는 메시지를 들어 보았다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.581-582
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• 2013

• Applied Chemistry for Engineering
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• v.25 no.2
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• pp.157-160
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• 2014

We examined and compared the feasibility of vegetable oils with synthetic thermal conductive oils to recover highly purified copper metal from waste jelly-filled communication cables. While polydimethylsiloxane shows relatively poor separation efficiency under entire operating conditions, dibenzyltoluene and waste vegetable oil show the high separation efficiency if the appropriate operating temperature and time were given. By running 50 kg-class equipment with waste vegetable oils, we obtained 100% copper metal recovery with 99.2% purity at $300^{\circ}C$ for 60 min.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.152-159
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• 2013

Experiments of emulsion particles state of using polyglycerol ester emulsifier and the stability in accordance with the change of time were conducted using several oil. Experimental results confirmed that there is little difference in the stability and particle size depending on the type of oil. Most stable oil with polyglycerol ester is polar oil of silicon series and fatty acid ester oil, hydrocarbon oil of the nonpolar oil (Mineral oil, squalane, polydecene) was the most unstable state. And vegetable oils showed the stable form of particles with polyglycerol ester emulsifier.

• Journal of Life Science
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• v.23 no.7
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• pp.879-885
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• 2013

Baby powder is an astringent powder used to prevent diaper rash. It also has other cosmetic uses. In general, it is composed of talc powder (talcum powder). Talc powder is harmful if inhaled because it can cause significant lung damage. With the aim of developing a new rice-based baby powder, three kinds of rice varieties were selected and pulverized. To determine the cost-effectiveness of the different states of rice powder, several milling processes were tried, and the powder characteristics of the resulting rice powder, such as particle size, biological activities, digitalized color value, and moisture content before and after coating treatment with essential oil and silicon oil, were examined. "Goami" showed good flour characteristics with respect to lightness (92.0, $L^*$[D65] value) and particle size ($8.9{\mu}m$). SEM analysis showed that the rice powder particles coated in the essential oil and silicon oil showed a smoother and rounder appearance than those of the talc powder. In addition, the average particle size was decreased by the essential oil and silicon oil coating. The silicon oil coating solved the problem of moisture absorption in rice flour. Rice flour properly coated with essential oil and silicon oil shows great potential as a new material source of powder.

• Resources Recycling
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• v.19 no.4
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• pp.51-57
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• 2010

As a recycling of Si sludge from Si wafer process, a Si-SiC-CuO-C composite material was synthesized and investigated as an anode material for lithium batteries. The Si sludge consisted of Si, SiC, machine oil, and metallic impurities. The oil and metal impurities was removed by organic washing, magnetic separation, and acid washing. The Si-SiC-CuO-C composite from the recovered Si-SiC mixture was prepared by high-energy mechanical milling. According to the electrochemical tests such as charge-discharge capacity and cycling behavior, it showed the improved cycle performance. The SiC and CuO-related phases were presumed to restrain the volume expansion of the anode and Fe, however, should be removed below 10 ppm prior to synthesis of the composite because it caused the capacity loss of the active material itself.