• 센서학회지
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• 제13권4호
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• pp.292-297
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• 2004

Carbon nanotubes (CNT) were synthesized by arc-discharge method. To fabricate CNT sensor, CNT powder was dispersed in ${\alpha}$-Terpinol($C_{10}H_{17}OH$) solution. The CNT tilms were fabricated by screen printing method on the interdigitated Pt/Pd alloy electrode. The microstructure of CNT film was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In order to investigate the gas sensing characteristics of the film, the CNT film was experimented to measure NO response and recovery time. The CNT sensor with a heater was compared to that without a heater. And this sensor shows better reproductibility and faster recovery time than another CNT sensors. We suggest the possibility to utilize a CNT as new sensing materials for environmental monitoring.

• 한국재료학회지
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• 제14권4호
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• pp.276-280
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• 2004

Carbon nanotubes(CNT) were synthesized by arc-discharge method. To fabricate CNT sensor, CNT powder was dispersed in $\alpha$-Terpinol($C_{10}$ $H_{17}$OH) solution. The CNT films were fabricated by screen printing on the interdigitated Pt/Pd alloy electrode. The microstructure of CNT film were observed by scanning electron microscopy (SEM). In order to investigate the gas sensing characteristics of the film, the CNT film was experimented to measure NH$_3$ response and recovery time. And this sensor shows better reproductibility and faster recovery time than another CNT sensors. We suggest the possibility to utilize a CNT as new sensing materials for environmental monitoring.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.181.2-181.2
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• 2014

A single-layer graphene has been uniformly grown on a Cu surface at elevated temperatures by thermally processing a poly (methyl methacrylate) (PMMA) film in a rapid thermal annealing (RTA) system under vacuum. The detailed chemistry of the transition from solid-state carbon to graphene on the catalytic Cu surface was investigated by performing in-situ residual gas analysis while PMMA/Cu-foil samples being heated, in conjunction with interrupted growth studies to reconstruct ex-situ the heating process. We found that the gas species of mass/charge (m/e) ratio of 15 ($CH_3{^+}$) was mainly originated from the thermal decomposition of PMMA, indicating that the formation of graphene occurs with hydrocarbon molecules vaporized from PMMA, such as methane and/or methyl radicals, as precursors rather than by the direct graphitization of solid-state carbon. We also found that the temperature for dominantly vaporizing hydrocarbon molecules from PMMA and the length of time, the gaseous hydrocarbon atmosphere is maintained, are dependent on both the heating temperature profile and the amount of a solid carbon feedstock. From those results, we strongly suggest that the heating rate and the amount of solid carbon are the dominant factors to determine the crystalline quality of the resulting graphene film. Under optimal growth conditions, the PMMA-derived graphene was found to have a carrier (hole) mobility as high as ${\sim}2,700cm^2V^{-1}s^{-1}$ at room temperature, which is superior to common graphene converted from solid carbon.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.549-552
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• 2012

Recently the world is trying to reduce carbon emissions for global warming. Reducing use of fossil fuels can decrease carbon emission. In this reason the construction field has tried to reduce the use of fossil fuels relating to heating and cooling of buildings. An energy loss through the window system is about 10 to 30 percent of energy consumption of the whole building. The use of window film insulation is increasing to control the heat loss at the windows. The window film insulation absorbs solar radiation and makes the surface temperature of windows high. In this study, window surface temperature is measured, and an impact on indoor air is identified after attaching window film insulation. Finally, we found that cooling load decreases through simulation.

• 전기전자학회논문지
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• 제22권1호
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• pp.213-215
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• 2018

본 연구에서는 실리콘 기판 위에 DC 스퍼터링 방법을 이용하여 비정질 탄소박막을 제작하고, 흡광특성과 광발열 특성을 조사하였다. 비정질 탄소박막은 1000 nm 파장에서 97%의 흡광도를 보였으며, 백색광이 조사됨에 따라 비정질 탄소박막의 온도는 $21.1^{\circ}C$에서 $24.1^{\circ}C$로 상승하여 약 $3^{\circ}C$의 온도가 증가하였다. 또한, 백색광이 50초 동안 조사되는 동안 비정질 탄소박막에서는 기판에 비해 4배 빠른 온도상승속도로 온도가 증가하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.530-530
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• 2012

Many practical applications of carbon nanotubes(CNTs) have been proposed and there have been attempts to utilize CNT films as transparent electrodes for solar cells and displays. Our group has considered the use of the CNT film as a thin film heater (TFH) and proposed it for the first time and reported the thermal behavior of the TFH made of single walled CNTs. However, due to the relatively high electrical resistance of the CNT film, using the TFH in application areas requiring high heat flux has been a difficult problem. To overcome this obstacle, we adopted a 'branch electrodes' concept to increase the film conductance dramatically. If two branch electrodes are inserted into a TFH whose original electrical resistance is R, the total resistance will be reduced to R/9. Because of the increased aspect ratio, the resistance of each segmented TFH will be reduced to R/3. Furthermore, since they are connected in parallel, the total resistance reduces to R/9. This could be extended to n branch electrodes, and the total resistance of the film will be reduced to R/(n+1)2, if the resistance of electrodes are negligibly small. We fabricated the heaters with different number of branch electrodes. The number of branch electrodes of the fabricated heaters are 0, 2, 4, 8 and their electrical resistance are 101.4, 39.5, 20.0, $15.4{\Omega}$, respectively. We applied 20V to each heater and monitored the temperature variations. We could achieve high heating temperature even with low voltage supply. This technique could be applied to relevant industrial applications which need high power film heater.

• Journal of Information Display
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• 제7권2호
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• pp.22-25
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• 2006

This paper presents heating process for obtaining standing carbon nanotube emitters to improve field-emission properties from the screen-printed multiwalled carbon nanotube (MWCNT) films. In an atmosphere with optimum combination of nitrogen and air for heat treatment of CNT films, the CNT emitters can be made to protrude from the surface. This allows for high emission current and the formation of very uniform emission sites without special surface treatment. The morphological change of the CNT film by this technique has eliminated additional processing steps, such as surface treatment which may result in secondary contamination and damage to the film. Despite its simplicity the process provides high reproducibility in emission current density which makes the films suitable for practical applications.

• 한국전기전자재료학회논문지
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• 제15권2호
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• pp.184-189
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• 2002

Carbon nitride films were grown on Si (100) substrate by a laser-electric discharge method with/without a magnetic field assistance. The magnetic field leads to vapor plume plasma expending upon the ambient arc discharge plasma area. Influence of the magnetic field has resulted in increased of a crystallite size int he films due to bombardment (heating) of Si substrates by energetic carbon and nitrogen species generated during cyclotron motion of electrons in the discharge zone. The surface morphology of the films with a deposition time of 2 hours was studied using a scanning electron microscopy (SEM). In order to determine the structural crystalline parameters, X-ray diffraction (XRD) was used to analysis the grown films.

• 생물환경조절학회지
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• 제31권1호
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• pp.8-13
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• 2022

본 연구는 동절기 공정육묘장의 수박 플러그 묘 생산 시, 난방 에너지 절감에 유리한 난방장치인 나노탄소섬유 적외선 난방등의 효율적인 사용을 위한 적정 전력과 설치 간격을 구명하기 위해 수행되었다. 유리온실 내 소형 베드 6개를 플라스틱 필름으로 구획을 나누었으며, 100cm 높이에 700W와 900W 난방등을 설치하였다. 난방등은 설치 간격을 각각 중앙 1개(Control), 60cm 간격(2개), 40cm 간격(3개)으로 설치하였다. 나노탄소섬유 적외선 난방등을 점등한 후 대조구를 제외한 모든 처리에서 설정한 야간 기온(20℃)을 유지하였다. 엽온은 난방등 설치 간격이 좁을수록 빨리 상승하는 경향을 보였다. 나노탄소섬유 적외선 난방등을 사용함에 따른 처리구간 수박 접목묘의 생육에는 뚜렷한 차이가 없었으나, 엽장과 엽폭은 700W 난방등에서 설치 간격이 짧을수록 길어지는 경향을 보였으며, 700W 난방등을 40cm 간격으로 설치하였을 때 묘의 충실도가 높은 값을 나타내는 것을 확인할 수 있었다. 따라서 야간 기온 유지와 묘의 충실도를 고려하였을 때, 700W 난방등을 40cm 간격으로 설치하는 것이 수박 접목묘를 생산하는데 경제성을 고려하여 효율적인 나노탄소섬유 적외선 난방등의 전력과 설치 간격으로 판단된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.131-131
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• 2013

A single-layer graphene has been uniformly grown on a Cu surface at elevated temperatures by thermally processing a poly(methyl methacrylate) (PMMA) film in a rapid thermal annealing (RTA) system under vacuum. The detailed chemistry of the transition from solid-state carbon to graphene on the catalytic Cu surface was investigated by performing in-situ residual gas analysis while PMMA/Cu-foil samples being heated, in conjunction with interrupted growth studies to reconstruct ex-situ the heating process. The data clearly show that the formation of graphene occurs with hydrocarbon molecules vaporized from PMMA, such as methane and/or methyl radicals, as precursors rather than by the direct graphitization of solid-state carbon. We also found that the temperature for vaporizing hydrocarbon molecules from PMMA and the length of time the gaseous hydrocarbon atmosphere is maintained, which are dependent on both the heating temperature profile and the amount of a solid carbon feedstock are the dominant factors to determine the crystalline quality of the resulting graphene film. Under optimal growth conditions, the PMMA-derived graphene was found to have a carrier (hole) mobility as high as ~2,700 cm2V-1s-1 at room temperature, superior to common graphene converted from solid carbon.