• Polymer(Korea)
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• v.33 no.5
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• pp.397-406
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• 2009

We have fabricated source-drain electrodes for OTFTs using a screen-printing technique with carbon-black pastes as conductive paste. And effects of dispersants contents (SOP 10-40%) on the dispersity of carbon-black pastes and characteristics of screen-printed source-drain electrodes for OTFTs using two types of dispersants (DB-2150, DB-9077) were investigated. As contents of both dispersants were increased the dispersity of carbon-black mill-bases was improved, whereas the carbon-black pastes exhibited different dispersion characteristics. For the case of DB-2150, the dispersity of the pastes was improved with increasing dispersant content and the storage modulus G' in their rheology characteristics were reduced. But, for the DB-9077, the storage modulus G' of pastes were increased with dispersant content due to the flocculated network structure formed by interactions among carbon-black powders and dispersants. But, since this flocculated network structure of the pastes using DB-9077 resulted in the conduction path of carbon-black structures, the conductivities of screen-printed electrodes and mobilities of the OTFTs with them were better than those using pastes with DB-2150.

• Clean Technology
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• v.27 no.4
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• pp.325-331
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• 2021

In this study, bio-carbons were produced by activation process from unused biomass (Grade 3 wood pellet and spent coffee grounds) to determine the removal performance of formaldehyde and acetaldehyde. The activation experiments were conducted in a fixed bed reactor using CO₂ as an activation agent. The temperature of the activation reactor and input of CO₂ were 900 ℃ and 1 L min^-1 for all the experiments. The maximum BET surface area of about 788 m² g^-1 was obtained for bio-carbon produced from Grade 1 wood pellet, whereas about 544 m² g^-1 was achieved with bio-carbon produced from spent coffee grounds. In all the experiments, the bio-carbons produced were mainly found to have micro-porous nature. A lower ash amount in raw material was favored for the high surface area of bio-carbons. In the removal test of formaldehyde and acetaldehyde, the bio-carbon produced from spent coffee grounds showed excellent adsorption performance compared with woody biomass (Grade 1 wood pellet and Grade 3 wood pellet). In addition, the comparative experiment of commercial impregnated activated carbon and bio-carbon produced from spent coffee grounds was conducted. In terms of formaldehyde removal performance, the commercial impregnated bio-carbon was excellent, while bio-carbon produced from spent coffee grounds was excellent in acetaldehyde removal.

• Journal of Energy Engineering
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• v.4 no.3
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• pp.309-314
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• 1995

촉매의 담지순서 카본블랙의 종류 및 전처리 방법 등을 달리하여 연료전지 전극용 백금/카본 분말을 제조하고 이것의 백금 유실율, 백금 분산율 및 촉매 활성을 살표보았으며, 이를 사용하여 제조한 전극의 단위전지 성능을 상용전극과 비교하였다. 실험결과 카본블랙에 백금용액을 먼저 혼합한 후 환원시키는 전극제조 방법은 기존의 콜로이달법 보다 백금의 유실율이 적고 분산율이 높았다. 그리고 산/염기를 이용한 카본블랙의 전처리는 표면적은 줄어들지만 촉매활성을 증가시켰으며, 전극촉매의 최적 활성화 온도는 30$0^{\circ}C$이었다.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.118-123
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• 1999

저밀도 폐놀계 탄소/탄소 복합재의 층간전단강도를 개선하기 위해 흑연분말, 카본블랙, 카본매트, 단섬유 등의 첨가제를 사용하였다. 카본매트와 단섬유를 첨가한 경우, 수지의 부족에 의한 층간접착력의 약화를 가져왔으며, 카본블랙을 첨가한 경우에도 큰 효과를 나타내지 못했다. 흑연을 첨가했을 때 약 30%의 층간강도 개선을 가져왔으며 특히 9 vol.%의 첨가량에 대해서 가장 큰 효과를 보였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.152-152
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• 2004

카본나노튜브(Carbon Nanotube)는 다른 물질과 구별되는 날카로움(Sharpness), 고세장비(High Aspect Ratio), 높은 기계적 강성(Stiffness), 고탄성(high Elasticity), 그리고 반도체(semi-conducting)와 도체(Metallic) 성질 때문에, 카본나노튜브는 많은 연구에 적용되고 있으며, 카본나노튜브가 부착된 AFM(Atomic Force Microscope) 팁을 이용한 AFM 측정은 CNT 응용에 있어서 매우 큰 효과를 내는 응용분야 중 하나이다. AEM 팁에 카본나노튜브를 붙이는 이전 연구는 대부분 화학증착법(Chemical Vapor Deposition)에 의해 이루어 졌으며, 매우 효과적인 방법이지만 고가의 장비와 고온의 챔버내에서 이루어진다는 문제점을 가지고 있다.(중략)

• Journal of the Microelectronics and Packaging Society
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• v.21 no.4
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• pp.77-82
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• 2014

Stretchable electrodes are focused due to many demands for soft electronics. One of the candidates, carbon black composites have advantages of low cost, easy processing and decreasing resistivity in a certain range during stretching. However, the electrical conductivity of carbon black composites is not enough for electronic devices. Graphene is 2-dimensional nanostructured carbon based material which shows good electrical properties and flexibility. They may help to improve electrical conductivity of the carbon black composites. In this study, graphene was added to a carbon black electrode to enhance electrical properties and investigated. Electrical resistivity of graphene added carbon electrode decreased comparing with that of carbon black electrode because graphene bridged non-contacting carbon black aggregates to strengthen the conductive network. Also graphene reduced an increase in the resistance of the carbon black electrode applied to strain because they connected gap of separated carbon black aggregates and aligned along the stretching direction at the same time. In conclusion, an addition of graphene to carbon black gives two benefits on the electrical properties of carbon black composite as a stretchable electrode.

• Journal of the Korean Chemical Society
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• v.47 no.2
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• pp.147-154
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• 2003

In this study, the fluorinated carbon blacks(CB) were used to reduce the negative temperature coefficient (NTC) phenomenon of the CB-filled high density polyethylene(HDPE) compounds in the fluorination pressure of 0.1-0.4 MPa. The changes in surface properties of the CB were investigated by using FT-IR, XPS and contact angle measurements. From the FT-IR results, the fluorinated CB showed the C-F absorption peak at 1400-1000 cm$^{-1}$ and the peak intensity was increased with increasing the fluorination pressure. Also, the analysis of XPS spectra of the fluorinated CB indicated that fluorine content was increased with increasing the fluorination pressure. Meanwhile, the surface free energy of the fluorinated CB was decreased with increasing the fluorination pressure. Consequently, the increase of fluorine contents on CB made a disappearance of NTC behaviors of CB/HDPE compounds, which was probably due to the reduction of CB reaggregation after melting point of the HDPE, resulting from decreasing the surface free energy of CB particles.

• Journal of the Korean Electrochemical Society
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• v.17 no.2
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• pp.124-129
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• 2014

In this article, we report the fabrication and characterization of carbon sphere/$Fe_3O_4$ nanocomposite for Li/air batteries. $Fe_3O_4$ nanoparticles are dispersed homogeneously on the surface of carbon spheres in an attempt to enhance the low conductivity of oxide catalyst ($Fe_3O_4$). The carbon sphere/$Fe_3O_4$ nanocomposite could offer wide surface area of $Fe_3O_4$ and increased carbon/catalyst contact area, which lead to enhanced catalytic activity. The electrode employing carbon sphere/$Fe_3O_4$ nanocomposite presented relatively low overpotential and stable cyclic performance compared with the electrode employing carbon sphere.

• The Journal of the Convergence on Culture Technology
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• v.4 no.2
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• pp.211-216
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• 2018

Separation technology combining adsorption and membrane is expected to be applied in many fields such as water treatment. In this fusion technique, a functional carbon membrane having a carbon whisker grown on the surface of the membrane was developed to inhibit membrane fouling, which is a problem in the membrane separation process. In this study, to elucidate the mechanism of manufacturing the functional carbon membrane, the membrane was pretreated with the polymer latex of each mixing ratio and the membrane was formed by the CVD (Chemical Vapor Deposition) method. The membrane was analyzed by scanning electron microscope (SEM), CHN analyzer (Elemental Analyzer), and X-ray diffraction (XRD). As a result, the diameter and density of carbon whiskers were higher in case of polyvinyl di-chloride (PVdC): polyvinyl chloride (PVC) = 4.5: 55. It seems possible to control the diameter and density of the carbon whiskers according to the hydrogen content of the polymer latex.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.1
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• pp.17-24
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• 2014

We measured black carbon concentration in rural area to understand the characteristic of atmospheric aerosol by comparing the black carbon concentration and meteorological factors such as PM10 concentration, relative humidity, temperature and wind velocity. A MAAP (Multi Angle Absorption Photometer) which is one of filter based equipments was used to measure black carbon concentration. Black carbon concentration was measured to be high from April to May and low from June to September. Black carbon concentration was proportional to PM10 concentration. Black carbon concentration was correlated to relative humidity. Black carbon concentration was inversely proportional to wind velocity and temperature. Finally, we suggest that the volume fraction of black carbon in the atmosphere can be estimated from the size, number concentration and absorption coefficient measured using the MAAP.