• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1167-1168
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• 2006

In this study, the pure iron powder was treated with aqueous phosphoric acid to produce phosphate insulating layer on the surface. After drying the powder, it was compacted in a mold with a diameter of 20mm at 800MPa. The powder compacts were then heat treated at $500^{\circ}C$ for 1 hour. The results showed that insulated iron powder was obtained with uniform phosphate layer by chemical reaction. With increased amount of phosphate layer, the core loss and density of compacts were decreased. It was also found that the addition of ethyl alcohol during insulating reaction resulted in improved core loss value.

• Korean Chemical Engineering Research
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• 제47권3호
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• pp.275-280
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• 2009

바나듐이 담지된 3차원 입방구조의 V-KIT-6를 Pluronic P123 공중합체를 구조형성제로 사용하고, 부탄올을 보조 계면활성제로 사용하여 TEOS와 $NH_4VO_3$로부터 수열합성법으로 제조하였다. 제조한 V-KIT-6는 좁은 기공분포(~6.0 nm)를 가지고 넓은 비표면적(${\sim}1,000m^2/g$)을 보여주었다. V-KIT-6에서 V의 배위 특성 등은 $^{51}V$ 스핀 공명 NMR과 ESR을 이용하여 분석하였다. 제조된 V-KIT-6는 테트라부틸 하이드로 퍼옥사이드(TBHP)를 산화제로 사용한 스티렌의 직접산화반응에서 우수한 촉매활성을 나타내었다.

• 한국막학회:학술대회논문집
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• 한국막학회 2002년도 추계 총회 및 학술발표회
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• pp.84-87
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• 2002

No Abstract, See Full Text

• Bulletin of the Korean Chemical Society
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• 제24권9호
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• pp.1361-1364
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• 2003

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.80-82
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• 2007

We have developed a series of fluorinated dimethacrylate copolymers. Our work has covered the synthesized derivatives of alignment materials, characterized the pretilt angle and uniformity of liquid crystal alignment layer. The pretilt angle can be tailored by using the fluorinated copolymer. Excellent uniformity was achieved as shown in experimental results.

• 한국안전학회지
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• 제32권3호
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• pp.21-27
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• 2017

Even if several chemical accident prevention systems such as PSM(Process Safety Management), RMP(Risk Management Plan), etc. have been carried out, many chemical accidents have still occurred at industrial plants in Korea. We describe the status of chemical industry and the trend of occurrence of chemical accidents in Korea. And this paper analyzes the recent chemical accidents in eight ways. These ways include chemical accident forms, ignition sources, sources of chemical equipment, human vs equipment/material causes, worker's working situation, employee scale, hazardous substances, week & time, fatalities of manufacture & contractor's workers. Finally we proposes the four representative prevention measures brought to result of cause analysis by accident statistics.

• Tribology and Lubricants
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• 제33권3호
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• pp.106-111
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• 2017

Sapphire is an anisotropic material with excellent physical and chemical properties and is used as a substrate material in various fields such as LED (light emitting diode), power semiconductor, superconductor, sensor, and optical devices. Sapphire is processed into the final substrate through multi-wire saw, double-side lapping, heat treatment, diamond mechanical polishing, and chemical mechanical polishing. Among these, chemical mechanical polishing is the key process that determines the final surface quality of the substrate. Recent studies have reported that the material removal characteristics during chemical mechanical polishing changes according to the crystal orientations, however, detailed analysis of this phenomenon has not reported. In this work, we carried out chemical mechanical polishing of C(0001), R($1{\bar{1}}02$), and A($11{\bar{2}}0$) substrates with different sapphire crystal planes, and analyzed the effect of crystal orientation on the material removal characteristics and their correlations. We measured the material removal rate and frictional force to determine the material removal phenomenon, and performed nano-indentation to evaluate the material characteristics before and after the reaction. Our findings show that the material removal rate and frictional force depend on the crystal orientation, and the chemical reaction between the sapphire substrate and the slurry accelerates the material removal rate during chemical mechanical polishing.

• Korean Chemical Engineering Research
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• 제43권5호
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• pp.549-559
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• 2005

최근에 환경오염과 자원고갈에 의해서 인류활동의 생태적 영향을 최소화하는 지속 가능한 산업 개발(sustainable industrial development)이 많은 관심을 받고 있다. 이를 위해서는 기존에 있던 산업단지를 환경친화적으로 변화시키거나 새로운 산업단지를 건설하여 개별 공장 내뿐만 아니라 한 산업단지 내의 각 기업들이 물질 및 에너지를 최대한 효율적으로 이용하는 생태산업단지로의 전환이 전 세계적으로 활발하게 이루어지고 있다. 생태산업단지(eco-industrial park, EIP)는 산업단지 내의 각 기업들이 물질, 용수 및 에너지를 최대한 폐기물, 에너지, 물질, 용수 등을 서로 효율적으로 재이용함으로써 경제, 환경, 사회적 이익을 얻는 것을 목표로 한다. 본 총설에서는 국내외 생태산업단지의 사례연구와 생태산업단지 개발의 중요한 기술들(에너지 교환, 물질 재이용, 용수 재이용, 환경영향평가)에 대하여 소개한다.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1875-1878
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• 2013

• 대한화학회지
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• 제32권2호
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• pp.156-158
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• 1988