• Title/Summary/Keyword: carbon

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Standardization Trends for Carbon Nanotubes

  • Oh, Kyung-Hui
    • Carbon letters
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    • v.10 no.1
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    • pp.1-4
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    • 2009
  • In this work, standardization trends related carbon nanotubes and international standardization activities in the ISO/TC229 and IEC/TC113 were introduced. The movement toward development of carbon nanotube standard began in the nanotechnology council under the IEEE in 2005. KATS has also run the carbon nanotube standardization committee to support commercialization of product containing carbon nanotube through standards since 2004. The Korean Standards such as KSD2711, 2712, 2717 were established.

Superhydrophobic carbon-based materials: a review of synthesis, structure, and applications

  • Meng, Long-Yue;Park, Soo-Jin
    • Carbon letters
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    • v.15 no.2
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    • pp.89-104
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    • 2014
  • Materials with appropriate surface roughness and low surface energy can form superhydrophobic surfaces, displaying water contact angles greater than $150^{\circ}$. Superhydrophobic carbon-based materials are particularly interesting due to their exceptional physicochemical properties. This review discusses the various techniques used to produce superhydrophobic carbon-based materials such as carbon fibers, carbon nanotubes, graphene, amorphous carbons, etc. Recent advances in emerging fields such as energy, environmental remediation, and thermal management in relation to these materials are also discussed.

Studies on the Current Carbon Black Industries (최근(最近) Carbon Black 산업(産業) 동향(動向) 고찰(考祭) (고무용(用) Carbon Black을 중심(中心)으로))

  • Hwang, Yoon-Tae;Lee, Chang-Se
    • Elastomers and Composites
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    • v.27 no.2
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    • pp.89-101
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    • 1992
  • This paper is concerned with analysis for market trend and technological tendency of rubber-use black among United state, Japan and Korea, Through this comparative analysis, the subjects with which domestic carbon black industry is confronted are : first, development of new grade carbon black such as high performance carbon black, Low rolling resistance carbon black and lower grit carbon black, Second, reduction of quality fluctuation, third, improvement of applied technology and fourth, strengthening the price competitiveness through process optimization and productivity increase.

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Mesoporous Carbon Electrodes for Capacitive Deionization (축전식 탈염 공정을 위한 메조포러스 탄소 전극)

  • Lee, Dong-Ju;Park, Jin-Soo
    • Journal of the Korean Electrochemical Society
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    • v.17 no.1
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    • pp.57-64
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    • 2014
  • Carbon electrodes for capacitive deionization were fabricated through mixing two different carbon powders (activated carbon powder, carbon black) with different particle sizes to investigate physical or electrochemical properties and finally desalination performances of the electrodes with various compositions of two carbon powders in weight and were compared with the electrode consisting of activated carbon. As a result, the electrode structure became more packed as increasing the amount of carbon black and resulted in 10% increase in mesopore fraction. The specific capacitance obtained from cyclic voltammograms of various electrodes showed that the electrode containing carbon black only had 107.4 F/g, while the specific capacitance of the electrode having more amount of carbon black increased and was higher than the one having no carbon black. The results of desalination runs in a capacitive deionization cell exhibited that the electrode having the highest amount of carbon black (1 wt%) in this study had the highest desalting efficiency, and no significant pH variation was observed during the runs. It was analyzed using accumulated charge that the fraction of non-Faraday current increased as the amount of carbon black increased in the electrodes. It can be concluded that the addition of carbon black changed the electrode structure resulting in an increase in the fraction of mesopore and finally enhanced the desalting efficiency by decreasing Faraday current.

Risk of Carbon Leakage and Border Carbon Adjustments under the Korean Emissions Trading Scheme

  • Oh, Kyungsoo
    • Journal of Korea Trade
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    • v.26 no.2
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    • pp.45-64
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    • 2022
  • Purpose - This paper examines South Korea's potential status as a carbon leakage country, and the level of risk posed by the Korean emissions trading scheme (ETS) for Korean industries. The economic effects of border carbon adjustments (BCAs) to protect energy-intensive Korean industries in the process of achieving the carbon reduction target by 2030 through the Korean ETS are also analyzed. Design/methodology - First, using the Korean Input-Output (IO) table, this paper calculates the balance of emissions embodied in trade (BEET) and the pollution terms of trade (PTT) to determine Korean industries' carbon leakage status. Analyses of the risk level posed by carbon reduction policy implementation in international trade are conducted for some sectors by applying the EU criteria. Second, using a computable general equilibrium (CGE) model, three BCA scenarios, exemption regulations (EXE), reimbursement (REB), and tariff reduction (TAR) to protect the energy-intensive industries under the Korean ETS are addressed. Compared to the baseline scenario of achieving carbon reduction targets by 2030, the effects of BCAs on welfare, carbon leakage, outputs, and trading are analyzed. Findings - As Korea's industrial structure has been transitioning from a carbon importing to a carbon leaking country. The results indicate that some industrial sectors could face the risk of losing international competitiveness due to the Korean ETS. South Korea's industries are basically exposed to risk of carbon leakage because most industries have a trade intensity higher than 30%. This could be interpreted as disproving vulnerability to carbon leakage. Although the petroleum and coal sector is not in carbon leakage, according to BEET and PTT, the Korean ETS exposes this sector to a high risk of carbon leakage. Non-metallic minerals and iron and steel sectors are also exposed to a high risk of carbon leakage due to the increased burden of carbon reduction costs embodied in the Korean ETS, despite relatively low levels of trade intensity. BCAs are demonstrated to have an influential role in protecting energy-intensive industries while achieving the carbon reduction target by 2030. The EXE scenario has the greatest impact on mitigation of welfare losses and carbon leakage, and the TAF scenario causes a disturbance in the international trade market because of the pricing adjustment system. In reality, the EXE scenario, which implies completely exempting energy-intensive industries, could be difficult to implement due to various practical constraints, such as equity and reduction targets and other industries; therefore, the REB scenario presents the most realistic approach and appears to have an effect that could compensate for the burden of economic activities and emissions regulations in these industries. Originality/value - This paper confirms the vulnerability of the Korean industrial the risk of carbon leakage, demonstrating that some industrial sectors could be exposed to losing international competitiveness by implementing carbon reduction policies such as the Korean ETS. The contribution of this paper is the identification of proposed approaches to protect Korean industries in the process of achieving the 2030 reduction target by analyzing the effects of BCA scenarios using a CGE model.

Manufacture of Pt-transition Metal Alloy Catalyst for PAFC (PAFC용 합금 촉매 제조)

  • Kim, Yeong-Woo;Lee, Ju-Seong
    • Applied Chemistry for Engineering
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    • v.4 no.4
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    • pp.692-700
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    • 1993
  • Corrosivities and catalytic activities of platinum-transition metal alloy catalyses loaded on carbon substrate and were studied by electrochemical method using a unit cell. And the analysis of Pt-alloy catalyst was conducted by x-ray diffractometer. Among the catalysts, the Pt-Mo/carbon, Pt-Fe-Co/carbon and Pt-Fe/carbon catalyst showed more excellent cathodic current densities than others. It was found that most of cathodic current density for the Pt-Mo/carbon electrode was $120mA/cm^2$. The current density of the Pt-Fe-Co/carbon was much higher than that of Pt/carbon, reaching $200mA/cm^2$.

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Purification of Multi Walled Carbon Nanotubes (Mwcnts) Synthesized by Arc Discharge Set Up

  • Malathi, Y.;Padya, Balaji;Prabhakar, K.V.P.;Jain, P.K.
    • Carbon letters
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    • v.11 no.3
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    • pp.184-191
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    • 2010
  • Carbon nanotubes are unique tubular structures of nanometer diameter and large length/diameter ratio. The nanotubes may consist of one up to tens and hundreds of concentric shells of carbons with adjacent shells separation of ~0.34 nm. Multiwalled carbon nanotubes were synthesized by arc-discharge technique. MWCNTs were formed at the cathode deposit along with other carbonaceous materials like amorphous carbon, graphite etc. However, to get the best advantage of carbon nanotubes in various advanced applications, these undesired carbonaceous materials to be removed which is a challenging task. In the present study, various techniques were tried out for purifying MWCNTs such as physical filtration, chemical treatment and thermal annealing. SEM, FTIR, TGA and BET techniques were used to characterize the CNTs at various stages. Results shows that suitable chemical treatment followed by thermal annealing under controlled flow of oxygen gives the better route for purification of carbon nanotubes.

Electromagnetic Interference Shielding Properties of CO2 Activated Carbon Black Filled Polymer Coating Materials

  • Hu, Quanli;Kim, Myung-Soo
    • Carbon letters
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    • v.9 no.4
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    • pp.298-302
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    • 2008
  • Carbon blacks could be used as the filler for the electromagnetic interference (EMI) shielding. The poly vinyl alcohol (PVA) and polyvinylidene fluoride (PVDF) were used as the matrix for the carbon black fillers. Porous carbon blacks were prepared by $CO_2$ activation. The activation was performed by treating the carbon blacks in $CO_2$ to different degrees of burnoff. During the activation, the enlargement of pore diameters, and development of microporous and mesoporous structures were introduced in the carbon blacks, resulting in an increase of extremely large specific surface areas. The porosity of carbon blacks was an increasing function of the degree of burn-off. The surface area increased from $80\;m^2/g$ to $1142\;m^2/g$ and the total pore volume increased from $0.14073\;cc{\cdot}g^{-1}$ to $0.9343\;cc{\cdot}g^{-1}$. Also, the C=O functional group characterized by aldehydes, ketones, carboxylic acids and esters was enhanced during the activation process. The EMI shielding effectiveness (SE) of raw N330 carbon blacks filled with PVA was about 1 dB and those of the activated carbon blacks increased to the values between 6 and 9 dB. The EMI SE of raw N330 carbon blacks filled with PVDF was about 7 dB and the EMI SE increased to the range from 11 to 15 dB by the activation.

Effect of Plasma Modification of Woven type Carbon Fibers on the Wear Behavior of Carbon Fiber/Epoxy Composites (평직 탄소섬유의 플라즈마 처리 및 이에 따른 탄소섬유/에폭시 복합재의 마모 특성)

  • Lee, Jae-Seok;Rhee, Kyong-Yop
    • Journal of the Korean Society for Precision Engineering
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    • v.27 no.12
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    • pp.113-118
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    • 2010
  • For a present study, woven type carbon fibers were surface-modified by oxygen plasma to improve adhesive strength between carbon fibers and epoxy. The change of hydrophilic properties by the plasma modification was investigated through the contact angle measurement and the calculation of surface energy of carbon fiber due to the oxygen plasma modification. FESEM and XPS analyses were performed to study the chemical and physical changes on the surface of carbon fibers due to the oxygen plasma modification. Pin-on-disk wear tests were conducted under dry condition using unmodified and plasma-modified carbon/epoxy composites to investigate the effect of plasma modification on the wear behavior of woven type carbon/epoxy composites. The results showed that the friction coefficient and the wear rate of plasma-modified carbon/epoxy composites were lower than those of unmodified carbon/epoxy composites, respectively. XPS analysis showed that new functional group of a carbonyl type was created on the carbon fibers by the $O_2$ plasma treatment, which enhanced adhesive strength between carbon fibers and epoxy, leading to improve wear properties

Carbon/TiO2 Prepared from Anatase to Pitch and their Photocatalytic Performance

  • Chen, Ming-Liang;Ko, Young-Shin;Oh, Won-Chun
    • Carbon letters
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    • v.8 no.1
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    • pp.6-11
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    • 2007
  • Carbon/$TiO_2$ composites were prepared by $CCl_4$ solvent mixing method with different mixing ratios. Since the carbon layers derived from pitch on the $TiO_2$ particles were porous, the Carbon/$TiO_2$ composite series showed a good adsorptivity and photo decomposition activity. The BET surface area for the carbon layer in the sample increases to increasing with pitch contents. The SEM results present to the characterization of porous texture on the Carbon/$TiO_2$ composite and pitch distributions on the surfaces for all the materials used. From XRD data, a weak and broad carbon peak of graphene with pristine anatase peaks were observed in the X-ray diffraction patterns for the Carbon/$TiO_2$. The EDX spectra show the presence of C, O and S with strong Ti peaks. Most of these samples are richer in carbon and major Ti metal than any other elements. Finally, the excellent photocatalytic activity of Carbon/$TiO_2$ with slope relationship between relative concentration (C/$C_0$) of MB and t could be attributed to the homogeneous coated pitch on the external surface by $CCl_4$ solvent method.