• 한국생산제조학회지
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• 제20권3호
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• pp.274-279
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• 2011

In this study, new abrasives that were composed of iron powder and carbon nanotube (CNT) particle were attempted to be abrasives for magnetic abrasive polishing. Because the CNT particles itself are very small ones with high hardness and magnetic strength, these properties are effective for magnetic abrasive polishing of nonmagnetic materials. As an experimental result for evaluating the machining characteristics in magnetic abrasive polishing, the CNT particles showed better performance than the conventional abrasives such as Fe and CBN powder.

• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1815-1818
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• 2006

Imogolite which has chemical composition, $(HO)_3Al_2O_3SiOH$, was synthesized with orthosilicate acid and aluminium chloride at low pH solution. It has extremely large aspect ratio with an external diameter of 2nm and the length of a few micrometers. The high aspect ratio of the imogolite could make the material as the filler for the high strength fiber and as the wire for the electronic applications. Here, Imogolite that derives considerable microporosity from a nanometer-sized tubular structure has been modified with a conducting polymer, polypyrrole. Its bonding and wiring structure were confirmed by IR and TEM. The measured conductivity after modification with polypyrrole increased with polypyrrole thickness at various voltage conditions.

• Transactions on Electrical and Electronic Materials
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• 제3권1호
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• pp.23-29
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• 2002

The electronic properties of Carbon Nanotube(CNT) are currently the focus of considerable interest. In this paper, the electronic properties of finite length effect in CNT for the carbon nano-scale device is presented. To Calculate the electronic properties of CNT, Empirical potential method (the extended Brenner potential for C-Si-H) for carbon and Tight Binding molecular dynamic (TBMD) simulation are used. As a result of study, we have known that the value of the band gap decreases with increasing the length of the tube. The energy band gap of (6,6) armchair CNT have the ranges between 0.3 eV and 2.5 eV. Also, our results are in agreements with the result of the other computational techniques.

• 정보저장시스템학회논문집
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• 제11권2호
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• pp.36-40
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• 2015

The demand for flexible devices including solar cells, memories and batteries has increased rapidly over the past decades. In most flexible devices, polymer-based materials are used to enable the mechanical deformations such as bending or folding. Shape Memory Polymers (SMPs) is a high molecular compound polymer with flexibility and shape recovery characteristics. In this work, flexible shape memory device was fabricated by simply coating the conducting material, carbon nano-tube (CNT), on a shape memory polymer. Furthermore, durability of the device under various type of mechanical deformations was assessed. It is believed that the result of this work will aid in realization of a stretchable and wearable electronic device for practical applications.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.648-649
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• 2006

The dry-milling technique was used for mixing and crushing oxides and graphite powders. The ratio of ball-to-powder was 30:1 and argon gas was filled in jar. The excess carbon was $10{\sim}20wt%$ of the stoichiometric amount. The dry-milling was carried for 20 hours. The mixed powders were reduced and carburized at $900{\sim}980^{\circ}C$ for 3 hours flowing Ar gas in tube furnace. The dry-milled powders showed the wide diffraction patterns of X-ray. The reactions of reduction and carburization were completed in 3 hours at $980^{\circ}C$. After the reactions, the mean size of WC particles was about 200 nm. The content of free carbon in WC/Co mixed powders was less as the reaction temperature increased.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 춘계학술발표회 초록집
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• pp.76-77
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• 2007

화학 기상 증착법 (Chemical Vapor Deposition)은 기체 원료의 화학반응을 이용하여 박막, 미립자, nano-tube등 고체 재료를 합성하는 증착 방법이며, 현재 공업적으로 확산되어 반도체 공정과 같은 박막제조에 이용되고 있다. 박막제조에 있어서 중요한 관심사인 기판의 증착률은 기판의 회전 속도에 의하여 영향 받을 수 있다. 따라서 본 연구에서는 최적의 회전 속도를 찾아내기 위해 박막특성에 직접적으로 연관이 있는 CVD 반응기 내의 유동특성을 유한체적법 (Finite volume method)과 SIMPLE (Semi-Implicit Method for Pressure-Linked Equation) 알고리즘을 사용하여 수치모사 하였고 기판에서 화학 반응을 계산하기 위해 Arrhenius 모델을 사용하였다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.255-255
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• 2012

The interactions between cells and nanotopographies are increasingly interested as nanotopographies that may be more efficient in promoting cell functions and, titanium nanotubes have attracted much attention. Titanium nanotube can be fabricated easily with precisely controlled diameters and lengths. Titanium nanotubes with the suitable tube dimensions have been observed to enhance bone cell functions, whereas, there is still some controversy. These nanotubes can also serve as carriers for drugs such as growth factors, antibacterial agents and other drugs and show promise in bone implant applications.

• Design & Manufacturing
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• 제13권3호
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• pp.24-28
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• 2019

In this study, a study was carried out that could effectively produce a heat dissipation effect on plastic materials. Using carbon nanotube (CNT), aluminum powder and plastic, the material properties were tested in 2 cases of compounding ratio. The test sample mold was designed and constructed prior to the experiment. The experiments include tensile strength, elongation rate, flexural strength, flexural elasticity rate, eye-jaw impact strength, gravity and thermal conductivity. Results from 60% and 70% mixture of aluminium to plastic were tested, and a 10% less combined result was a relatively good property. For research purposes, the heat dissipation effect and light weighting obtained a good measure when the combined amount of Al was 60%.

• Design & Manufacturing
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• 제13권3호
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• pp.6-10
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• 2019

In this study, a study was carried out that could effectively produce a heat dissipation effect on plastic materials. Using carbon nanotube (CNT), aluminum powder and plastic, the material properties were tested in 2 cases of compounding ratio. The test sample mold was designed and constructed prior to the experiment. The experiments include tensile strength, elongation rate, flexural strength, flexural elasticity rate, eye-jaw impact strength, gravity and thermal conductivity. Results from 60% and 70% mixture of aluminium to plastic were tested, and a 10% less combined result was a relatively good property. For research purposes, the heat dissipation effect and light weighting obtained a good measure when the combined amount of Al was 60%.

• ETRI Journal
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• 제43권4호
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• pp.717-727
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• 2021

In this study, new multiplier and adder method designs with multiplexers are proposed. The designs are based on quaternary logic and a carbon nanotube field-effect transistor (CNTFET). The design utilizes 4 × 4 multiplier blocks. Applying specific rotational functions and unary operators to the quaternary logic reduced the power delay produced (PDP) circuit by 54% and 17.5% in the CNTFETs used in the adder block and by 98.4% and 43.62% in the transistors in the multiplier block, respectively. The proposed 4 × 4 multiplier also reduced the occupied area by 66.05% and increased the speed circuit by 55.59%. The proposed designs are simulated using HSPICE software and 32 nm technology in the Stanford Compact SPICE model for CNTFETs. The simulated results display a significant improvement in the fabrication, average power consumption, speed, and PDP compared to the current bestperforming techniques in the literature. The proposed operators and circuits are evaluated under various operating conditions, and the results demonstrate the stability of the proposed circuits.