• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1839-1842
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• 1999

We have synthesized carbon nanotubes by thermal chemical vapor deposition of $C_2H_2$ on transition metal-coated silicon substrates. Carbon nanotubes are uniformly synthesized on a large area of the plain Si substrates, different from Previously reported porous Si substrates. It is observed that surface modification of transition metals deposited on substrates by either etching with dipping in a HF solution and/or $NH_3$ pretreatment is a crucial step for the nanotube growth prior to the reaction of $C_2H_2$ gas. We will demonstrate that the diameters of carbon naotubes can be controlled by applying the different transition metals.

• Bulletin of the Korean Chemical Society
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• 제35권3호
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• pp.905-907
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• 2014

The plasma and microwave surface treatments of carbon nanotubes that loaded on plastic substrates were carried out with expecting a change of carbon nanotube dispersion by increasing treatment time. The microwave treatment process was undergone by commercial microwave oven (800 W). The electrical property was measured by hall measurement and resistance was increased by increasing $O_2$ flow rate of plasma, suggesting an improvement of carbon nanotube dispersion and a possibility of controlling the resistances of carbon nanotubes by plasma surface treatment. The resistance was increased in both polyethylene terephthalate and polyimide substrates by increasing $O_2$ flow rate. Resistance changes only slightly with different $O_2$ flow treatment in measure rho for all polyimide samples. Sheet resistance is lowest in polyimide substrate not due to high carbon nanotube loading but due to tendency to remain in elongated structure. $O_2$ or $N_2$ plasma treatments on both polyethylene terephthalate and polyimide substrates lead to increase in sheet resistance.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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• pp.163-164
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• 2012

Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition system. The substrate with oxygen incorporation and the substrate without oxygen incorporation were employed to elucidate the effect of substrate on the formation of carbon coils. The characteristics (formation densities, morphologies, and geometries) of the deposited carbon coils on the substrate were investigated. In case of Si substrate, the microsized carbon coils were dominant on the substrate surface. While, in case of oxygen incorporated substrate, the nanosized carbon coils were prevail on the substrate surface. The cause for the different geometry formation of carbon coils according to the different substrates was discussed in association with the different thermal expansion coefficient values between the substrate with oxygen incorporation and the substrate without oxygen incorporation.

• 미생물학회지
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• 제31권3호
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• pp.214-217
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• 1993

Carbon monoxide dehydrogenase (CO-DH) was found to be present in Acinetobacter sp. strain JC1 grown on CO and also on methylotrophic and heterotrophic substrates, except for pyruvate and nutrient broth. The amounts of CO-DH in cells grown on methylamine, glucose, galactose, and succinate were comparable to that of the CO-grown cells. CO-DH activity, however, was onot deteted by the dye-linked assay method in cell extracts prepared from cells grown on organic substrates, except on ethanol and succinate. THe activity was detected when the CO-DH was stained by activity using CO as a substrate. CO-DHs in cells grown on different substrates were found to be identical in immunological properties.

• 한국연소학회지
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• 제8권2호
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• pp.27-33
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• 2003

Synthesis of carbon nanomaterials on a metal substrate by an ethylene fueled inverse diffusion flame was illustrated. Stainless steel plates were used for the catalytic metal substrate. The effects of catalyst metal particles were investigated through $Fe(NO_3){_3}$ (ferric nitrate, nonahydrate) and $Ni(NO_3){_2}$ (nickel nitrate, hexahydrate). Carbon nanotubes and nanofibers with diameters of $30{\sim}70nm$ were found on the substrate for the case of using SUS304 substrates only and using them with metal nitrates. In case of using metal nitrates, due to the easy activation of the metal particles, the formation and growth of carbon nanomaterials were occurred in the lower temperature region than that of using SUS304 substrates only.

• 한국전기전자재료학회논문지
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• 제16권12호
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• pp.1103-1109
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• 2003

Crystalline carbon nitride films have been deposited by RF reactive magnetron sputtering system with negative DC bias. The carbon nitride films deposited on various substrates showed ${\alpha}$- C$_3$N$_4$,${\beta}$-C$_3$N$_4$ and lonsdaleite structures through XRD and FTIR We can find the grain growth of hexagonal structure from SEMI photographs, which is coincident with the theoretical carbon nitride unit cell. When nitrogen gas ratio is 70 % and RF power is 200 W, the growth rate of carbon nitride film on quartz substrate is about 2.1 $\mu\textrm{m}$/hr.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.212-212
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• 2000

Since the first obserbvation of carbon nanotubes, extensive researches have been done for the synthesis using arc discharge, laser vaporization, and plasma-enhanced chemical vapor deposition. Carbon nanotubes have unique physical and chemical properties and can allow nanoscale devices. Vertically aligned carbon nanotubes with high quality on a large area is particularly important to enable both fundamental studies and applications, such as flat panel displays and vacuum microelectronics. we have grown vertically aligned carbon nanotubes on a large area of Si substrates by thermal chemical vapor deposition using C2H2 gas at 750-950$^{\circ}C$. we deposited catalytic metal on Si susbstrate using thermal evaporation. The nanotubes reveal highly purified surface. The carbon nanotubes have multi-wall structure with a hollow inside and it reveals bamboo structure agreed with base growth model. Figure 1 shows SEM micrograph showing vertically aligned carbon nanotubes whih were grown at 950$^{\circ}C$ on a large area (20mm${\times}$30mm) of Si substrates. Figure 2 shows TEM analysis was performed on the carbon nanotubes grown at 950$^{\circ}C$ for 10 min. The carbon nanotubes are multi-wall structure with bamboo shape and the lack of fringes inside the nanotube indicates that the core of the structure is hollow. In our experiment, carbon nanotubes grown by the thermal CVD indicate base growth model.

• 한국재료학회지
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• 제25권7호
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• pp.341-346
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• 2015

The feasibility of obtaining graphitic carbon films on targeted substrates without a catalyst and transfer step was explored through the pyrolysis of the botanical derivative camphor. In a horizontal quartz tube, camphor was subjected to a sequential process of evaporation and thermal decomposition; then, the decomposed product was deposited on a glass substrate. Analysis of the Raman spectra suggest that the deposited film is related to unintentionally doped graphitic carbon containing some $sp-sp^2$ linear carbon chains. The films were transparent in the visible range and electrically conductive, with a sheet resistance comparable to that of graphene. It was also demonstrated that graphitic films with similar properties can be reproduciblyobtained, while property control was readily achieved by varying the process temperature.

• Carbon letters
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• 제12권2호
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• pp.90-94
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• 2011

We present the effect of a coupling agent on the optoelectrical properties of few-walled carbon nanotube (FWCNT)/epoxy resin hybrid films fabricated on glass substrates. The FWCNT/epoxy resin mixture solution was successfully prepared by the direct mixing of a $HNO_3$-treated FWCNT solution and epoxy resin. FWCNT/binder hybrid films containing different amounts of the coupling agent were then fabricated on UV-ozone-treated glass substrates. To determine the critical binder content ($X_c$), the effects of varying the binder content in the FWCNT/silane hybrid films on their optoelectrical properties were investigated. In this system, the $X_c$ value was approximately 75 wt%. It was found that above $X_c$, the coupling agent effectively decreased the sheet resistance of the films. From microscopy images, it was observed that by adding the coupling agent, more uniform FWCNT/binder films were formed.

• 한국토양환경학회지
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• 제5권1호
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• pp.97-108
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• 2000

원유를 탄소원으로 이용할수 있는 그람 음성 박테리아가 도시하수 처리장의 활성슬러지로부터 단리되어 Acinetobacter속으로 동정되었다. 이 균은 원유중의 알칸과 미확인된 다종의 한화수소를 분해할 수 있었으며 소수성 기질인 알칸을 단일 탄소원으로 이용하여 증식할수 있었다. 원유중 탄소수 13-30의 알칸은 동시에 분해가 진행되었으며 한소수의 짝수, 홀수에 따른 분해특성의 차이는 보이지 않았다. 균의 선형적인 증식과 알칸 성분의 분해특성으로부터, 원유상에서 기질의 초기 산화가 진행되는 미생물부위까지 물질전달이 분해과정의 율속이 됨을 알수 있었다. 분해 진행후 반응계내 알칸의 잔류 현상이 관찰되었는데 이는 Acinetobacter 속의 특성으로 알려져있는 세포내 탄화수소 함유체의 영향으로서 원유로 부터의 물질전달을 제어하는 요인이 될수 있음을 시사하였다. 따라서 본 균은 환경중 잔류하는 소수성 오염물질의 분해메카니즘 연구에 중요한 역할을 한다고 사료된다.