• Textile Coloration and Finishing
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• v.19 no.4
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• pp.26-31
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• 2007

Nanocomposite resin(PUD-CNT) composed of Carbon nanotube(CNT) and Polyurethane Dispersion (PUD) was prepared by different contents of CNT($0{\sim}5%$). PUD-CNT was coated on samples, and their electrical conductivity was investigated. With increasing CNT content, static change, half life and surface resistance decreased. Composites having 5% CNT showed $10^9{\Omega}/cm$(surface resistance), and 40V (stactic charge). Respectively, From this results, PUD-CNT can be used as a antistatic material.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.53-53
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• 2014

아연-마그네슘 합금은 뛰어난 내식성으로 최근 코팅소재로 가장 많이 사용되는 아연 도금을 대체할 수 있는 재료로서 주목받고 있다. 특히 PVD 방식을 통해 도금강판을 제조할 경우 도금층의 두께 제어가 용이하여 아연의 사용량을 저감할 수 있다. 그러나 이러한 PVD 방식을 통해 제조된 아연-마그네슘 도금강판을 사용하기 위해서는 내식성 이외에도 일정수준의 기계적 특성 확보가 중요하다. 본 연구에서는 마그네슘 함량을 달리하여 제조된 아연-마그네슘 도금강판을 대상으로 XRD 분석, 나노인덴테이션 시험을 실시하여, 아연-마그네슘 도금강판 도금층의 기계적 특성에 미치는 상(Phase)의 영향을 분석하였다.

• Journal of the Semiconductor & Display Technology
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• v.19 no.3
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• pp.36-42
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• 2020

Silver nanowire (AgNW) random-meshes with high transmittance, low sheet resistance, and high oxidation stability and flexibility were fabricated using solution-based processes. The random-mesh structure was obtained by forming bubbles whose sizes and densities were controlled using a corona treatment of polyethylene terephthalate (PET) substrates. To reduce the sheet resistance of the fabricated AgNW electrode, a washing process using ethanol solution was performed. In addition, nickel (Ni) was coated on AgNW to improve resistance to oxidation. The effects of corona treatment and Ni-coating on the transmittance, sheet resistance, oxidation stability, and flexibility of the AgNW electrodes were investigated.

• Transactions of Materials Processing
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• v.13 no.8
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• pp.731-737
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• 2004

Mechanical properties such as Young's modulus and hardness of thin film in coated steel are difficult to determine by nano-indentation from the conventional analysis using the load-displacement curve. Therefore, an analysis of the nano-indentation loading-unloading curve was used to determine the Young's modulus, hardness. A new method is recently being developed for elastic-plastic properties of materials from nano-indentation. Elastic modulus of the thin films shows relatively small influence whereas yield strength is found to have significant effect on measured data. The load-displacement curves of material tested with a Berkovich indenter and nano-indentation continuous stiffness method is used to measure the modulus and hardness through thin films, and then these are computed using the analysis procedure. The developed neural networks apply also to obtain reliable mechanical properties.

• Mineral and Industry
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• v.29
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• pp.1-17
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• 2016

점토광물은 자연 산출되는 광물로써 양이 풍부하고 가격이 저렴하여 여러 가지 산업자원으로써 오래전부터 다양하게 활용되어 왔다. 전통적인 주요 활용분야로는 제지 및 코팅 산업의 충진제, 내화재, 세라믹, 유리섬유, 시멘트 등에 90% 이상이 사용되어왔다. 최근에야 고무, 플라스틱 및 페인트의 물성 강화용 충진제로, 넓은 표면적을 활용한 촉매제로 일부 사용되고 있지만 대부분 판상용 점토광물을 대상으로 하고 있다. 고령토가 국내 생산 주요 품목에 들어가지만 그 비중은 2014년 기준 1.9%로 낮으며, 그나마 자급율도 77% 수준이라 수입에 의존하고 있다. 생산되는 고령토의 양이 매년 감소하고 있는 추세이며, 2014년 기준 고품질인 Wa와 Wb의 생산량이 각각 600 톤과 227 톤으로 미미한 수준이며 P급이 4.1만 톤 수준이라 부가가치가 매우 낮은 상품 중의 하나로 보인다. 다행히 우리나라에서 생산되는 고령토의 많은 부분이 할로이사이트 계열 고령토이고, 할로이사이트의 독특한 나노튜브 형태는 신소재 개발과 더불어 부가가치가 높은 새로운 활용분야를 개척하기 아주 적절한 광물이어서 그 특성과 산업적 활용 특성을 중심으로 최신 연구동향과 활용분야를 소개하고자 한다.

• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.185-195
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• 2011

Carbon nanotube(CNT) plays an essential role in various fields of nano based science and technology. Recently, silica coated CNT composites are interested because they are useful for the optical, magnetical, and catalytic applications. In this report, carboxyl groups were introduced on the MWCNT using nitric acid. In order to maximize the silica encapsulation efficiency, carboxyl groups of MWCNT reacted with a silane coupling agent were used to prepare silica coated MWCNT. Due to their strong interaction between modified MWCNT and TEOS. Silica layer with a controllable thickness was achieved. Silica coated MWCNT were further utilized as the template for the synthesis of hollow silica nanotubes after $800^{\circ}C$ calcination.

• Journal of the Semiconductor & Display Technology
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• v.18 no.3
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• pp.36-41
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• 2019

Hybrid-type transparent electrodes were fabricated by depositing carbon nanotubes (CNTs) via spray coating on polyethylene terephthalate (PET) substrates and then coating the CNTs with [poly(3,4-ethylenedioxythiophene)] (PEDOT) films via electro-polymerization. For all of the fabricated electrodes, their surface morphologies, electric sheet resistances, visible transmittances, and color properties (e.g., yellowness) were characterized as functions of the applied voltages and process times used in electro-polymerization. The sheet resistance of the CNTs was significantly reduced by the coating of PEDOT, while their visible transmittances slightly decreased. The yellowness values of the PEDOT-coated CNTs were observed to have substantially decreased via electro-polymerization. The experimental results confirmed that the fabricated hybrid electrodes had desirable properties for the application of transparent electrode in terms of the electrical resistance, optical transmittance, and chromaticity.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.104-105
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• 2002

Ni$_{1-x}$-Zn$_{x}$ ferrite는 매우 큰 저항과 적은 eddy current loss를 가지고 있어 transfomer core나 radio frequency coil같은 high power device등의 전자 재료로 이용된다[1]. Ni$_{1-x}$-Zn$_{x}$ ferrite의 합성에는 여러 가지 방법이 이용되고 있으나 oxide/carbonate를 이용하여 120$0^{\circ}C$ 이상의 고온의 열을 가해 하소하는 solid-state reation과 diethylamine을 이용하여 metal nitrate를 공침 하는 coprecipition방법, sol-gel 방법 등의 wet chemical method가 가장 일반적이다[2-3]. (중략)

• Journal of the Semiconductor & Display Technology
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• v.12 no.3
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• pp.1-6
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• 2013

In many technical fields including electronics and display manufacturing processes, properties of coating liquids could be greatly enhanced by adding nanopowders and it requires efficient mixing techniques to achieve uniform dispersion of nanoparticles in liquids. This paper presents the three-dimensional CFD simulations on the flowfields of a highly viscous liquid in the large scale industrial mixer of impeller type. The effects of several important design and operation parameters such as impeller geometry, rotational speed, and degree of liquid viscosity are investigated to appreciate the mixing performance by examining the computational results for flow pattern of rotationally stirred liquid of high viscosity in the mixer.

• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.317-320
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• 2006

본 연구는 고효율의 광촉매 제조와 그것의 환경적 응용에 관한 것이다. 가시광 영역에서도 $TiO_2$와 유사한 빛 흡수와 광분해속도를 갖는 나노 광촉매를 제조하였고, 낮은 온도에서도 활성 높은 rutile상이 형성하는 $SiO_2$위에 분산된 $TiO_2$광촉매를 제조하였다. 또한, 광촉매에 적용 가능한 바인더와 안정한 $TiO_2$ 광촉매 졸을 제조하였다. 이와 같은 물질들은 자외선/가시광선 분광광도계, X선 회절분석기, SEM, 광촉매활성 측정과 $TiO_2$ 코팅 표면의 물성으로 평가하였다. 이 결과들은 공기정화를 위하여 POF나 금속판을 이용하는 효율적인 광전자촉매시스템에 적용 할 수 있다.