• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.28-33
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• 2009

This study examined the mounting status of cigar lighter receptacles for vehicles and analyzed the tracking phenomenon that occurs when foreign material entered a cigar lighter receptacle to obtain data for the analysis of accident investigation. Regardless of the vehicle's output, cigar lighter receptacles are mounted in a vehicle horizontally, vertically, or at tilting or inclined angle. The tilting type cigar lighter receptacle is much easier to use but current leakage resulting from foreign materials (coffee, beverages, water, etc.) falling into the cigar lighter receptacle may cause a fire to start. This study used a vehicle battery (DC 12V) as a power supply for the tracking test and configured its circuit in the same way as that of an electrical device in a vehicle. The tracking phenomenon that occurred in the standby mode of the vehicle exhibited a fine flame and an irregular occurrence of smoke. While this tracking phenomenon was occurring, the leakage current and the reaching distance of the flame were measured to be approximately 930mA and $20{\sim}50cm$, respectively. It is thought that the resultant flame may ignite toluene, dust, cigarettes, etc. It was observed that as the tracking progressed, the internal metal socket melted and a hole was created, the surface of which was also severely carbonized. In addition, the electrical resistance of the carbonized conductive path was measured to be approximately $30{\Omega}$. It is thought that this much resistance may cause local heating when leakage current flows and could ignite any nearby flammable material.

• Membrane and Water Treatment
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• v.9 no.2
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• pp.95-104
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• 2018

Copper pollution around the world has caused serious public health problems recently. The heavy metal adsorption on traditional membranes from wastewater is limited by material properties. Different adsorptive materials are embedded in the membrane matrix and act as the adsorbent for the heavy metal. The carbonized leaf powder has been proven as an effective adsorbent material in removing aqueous Cu(II) because of its relative high specific surface area and inherent beneficial groups such as amine, carboxyl and phosphate after carbonization process. Factors affecting the adsorption of Cu(II) include: adsorbent dosage, initial Cu(II) concentration, solution pH, temperature and duration. The kinetics data fit well with the pseudo-first order kinetics and the pseudo-second order kinetics model. The thermodynamic behavior reveals the endothermic and spontaneous nature of the adsorption. The adsorption isotherm curve fits Sips model well, and the adsorption capacity was determined at 61.77 mg/g. Based on D-R model, the adsorption was predominated by the form of physical adsorption under lower temperatures, while the increased temperature motivated the form of chemical adsorption such as ion-exchange reaction. According to the analysis towards the mechanism, the chemical adsorption process occurs mainly among amine, carbonate, phosphate and copper ions or other surface adsorption. This hypothesis is confirmed by FT-IR test and XRD spectra as well as the predicted parameters calculated based on D-R model.

• Mycobiology
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• v.42 no.1
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• pp.17-21
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• 2014

Graphis upretii is a new lichen species discovered in Vietnam. The species is characterized by a loosely corticate, rough, whitish grey to greyish green thallus, elongate and irregularly branched lirellae with an apically thin complete thalline margin (negrosina morph), laterally carbonized, entire proper exciple, clear hymenium, hyaline, 16~20 transversely locular ascospores, and about $50{\sim}95{\times}10{\sim}15{\mu}m$ in size. In addition, members of the taxon produce norstictic and stictic acids. Currently, the lichen flora of Vietnam include Arthonia radiata, Brigantiaea tricolor, Coenogonium implexum, Dirina paradoxa, Herpothallon sipmanii, Pertusaria pertusa, and Sarcographina cyclospora.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.16-21
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• 1999

국민소득의 증대와 더불어 향상된 우리의 식생활 문화는 양보다 품질을 선호하게 되어 청정 농산물의 수요가 증대하였는데 이로 인하여 농작물의 유해성을 감소시킬 수 있으며 기후의 영향을 덜 받아 연중재배 및 생산이 가능한 수경재배 및 양액재배 기술이 등장하였으며, 이를 위한 첨단 시설하우스의 설립도 매우 많이 증가하였다. 또한 점점 더 확산되는 집단육묘 체계에서 살균 처리하여 사용되고 있는 관행 상토를 대체할 수 있는 무균의 배양토 재료의 개발이 관심 대상으로 떠올랐다. 토양 및 광물질, 유기물류가 혼합된 대부분의 상토재료(피트모스, 나무껍질)와 양액재배 지주물질은 매우 많은 양이 수입에 의존하고 있는 실정이다. 이러한 고가의 수입자재를 대체하기 위한 일환으로 우리 농촌에서 농업부산물로 생겨나는 왕겨를 탄화시켜 상토재료 및 양액재배용 지주물질로 사용하려는 연구가 다수 시행되었다. (중략)

• Mycobiology
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• v.43 no.2
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• pp.118-121
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• 2015

Graphis yunnanensis is described here as a new species. It is taxonomically well characterized by entire labia, slit-like disc, lateral thalline margin, completely carbonized proper exciple, inspersed hymenium, 8-spored asci, muriform $25{\sim}45{\times}8{\sim}12{\mu}m$ ascospores, and the presence of norstictic and stictic acids. The separation of the new species from other somewhat similar Graphis species is discussed. In addition, the study includes Graphis tenoriensis and Phlyctis karnatakana reported for the first time from China.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.11
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• pp.837-842
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• 2010

This paper describes the crystallinity, growth rate, and surface morphology of single crystalline 3C-SiC (cubic silicon carbide) thin films grown with several carbonization conditions such as temperature, $C_3H_8$ flow rate, time. In case of carbonization, an increase in the carbonization temperature caused a increase in the size and numbers of unsealed void (big black spot) which decrease the crystallinity. In addition, optimal $C_3H_8$ flow rate made carbonization layer form well and prevented the formation of voids. Also, after a period of time, the growth of carbonization layer did not increase no more. The single crystalline 3C-SiC thin films on optimal carbonized Si substrate showed an improvement on the crystallinity, the growth rate, the roughness, and the carrier concentration.

• Carbon letters
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• v.2 no.3_4
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• pp.165-169
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• 2001

Modification of C/C composite bipolar plate for improving electrical conductivity was carried out by addition of electroconductive carbon black (EC-CB). Carbon black was carefully mixed to methanol-containing phenolic resin, impregnated into 2D-carbon fabrics, hot pressed and then carbonized to obtain composite plate. Inclusion of electro-conductive carbon black enhanced the electrical conductivity of the C/C composites by increasing the conduction path. Addition of 10 vol% carbon black increased the electrical conductivity from 5.5/${\Omega}cm$ to 32/${\Omega}cm$ and reduced the crack formation by filling effect, resulting in the increase of flexural properties of composite plate. However, at carbon black content over 10 vol%, flexural properties decreased by delaminating role of excess carbon black at the interface in C/C composites.

• Journal of Institute of Convergence Technology
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• v.3 no.1
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• pp.45-49
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• 2013

Spherical active carbon materials have been used for the removal of pollutants in the area of food processing, water treatment, air purification, oral administration. Moreover, they are now expected to make an epoch in the areas of electronics, life science, environmental technology, and so on due to their superior physical properties. Carbon particles should be requested for the edgeless spherical shapes in order to minimize the loss due to the abrasion during the process and/or practical use, but the carbon particles manufactured from petroleum-based pitch do not meet these needs. Nowadays, thus, the spherical active carbon particles carbonized from various spherical polymer beads are studied with thermoplastic and/or thermosetting polymers. In this paper, the synthesis of spherical phenolic beads and furan beads, which are thermosetting polymers, and their carbonization techniques are examined.

• Proceedings of the KIEE Conference
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• 2006.05a
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• pp.57-59
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• 2006

In this study, we experimented a deterioration characteristics by series arcing with 600V polyvinyl chloride insulation wire and analyzed the glowing/growing process of copper oxide, waveforms of contact voltage, current, power dissipation and carbonized patterns of insulation. We know that how glowing contacts and surface arcing can decompose PVC insulation and that it is possible for the subsequent series arc to ignite, and burn insulation. We expect that these results are useful for advancing the state-of-the-art in fire protection by Providing a better understanding of how electrical fires can initiate.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.2121_2122
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• 2009

In this paper, we analyzed carbonization pattern of Ligth Emitting Diode(LED) lamp that become burnout by outside flame. Surface side can know that void is formed greatly than central part in section analysis of electric wire that is carbonized by outside flame. Chared globe displayed special quality that lump of abnormal carbonization falls was formed, and becomes melting among carbonization process. The LED resistance of forward direction is about 1.74 [$M{\Omega}$], and backward resistance is about 140 [$M{\Omega}$]. We can know progress direction of flame through measurement of the LED resistance.