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Effect of carbonization temperature on crystalline structure and properties of isotropic pitch-based carbon fiber
Jung Dam Kim, Jae-Seung Roh, Myung-Soo Kim 한국탄소학회 Carbon Letters 10 Pages
한국탄소학회 Carbon Letters 2017, Vol.21 6 51-60 (10 pages)
the carbonization temperature. The in-plane crystallite size (La) of the carbonized pitch fiber from X-ray diffraction increased monotonously by increasing the carbonization temperature resulting in a gradual increase in the electrical conductivity from 169 to 3800 S/cm. However, the variation in the d002 spacing and stacking height of the crystallite (Lc) showed that the structural order perpendicular to the graphene planes got worse in carbonization temperatures from 800 to 1200oC probably due... -
Effects of carbonization temperature on pore development in polyacrylonitrile-based activated carbon nanofibers
Hye-Min Lee, Kay-Hyeok An, Byung-Joo Kim 한국탄소학회 Carbon Letters 5 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.2 13 146-150 (5 pages)
as electrodes for electrical double-layer capacitors. The experimental results showed that the surface morphology of the CNFs was not significantly changed after the carbonization process, although their diameters gradually decreased with increasing carbonization temperature. It was found that the carbon content in the CNFs could easily be tailored by controlling the carbonization temperature. The specific capacitance of the prepared ACNFs was enhanced by increasing the carbonization temperature... -
Effect of acid catalysts on carbonization temperatures for ordered mesoporous carbon materials
Jeong Kuk Shon, Xing Jin, Yun Seok Choi, Jong Gu Won, Yoon Kyung Hwang, Dae Jong You, Chengbin Li, Ji Man Kim 한국탄소학회 Carbon Letters 6 Pages
한국탄소학회 Carbon Letters 2016, Vol.20 10 66-71 (6 pages)
on a conventional thermal process at high temperature (typically above 900°C), are time- and energy-consuming processes. In order to oligomerize or polymerize the carbon precursors before the carbonization, an aging process should also be carried out in the presence of acid catalysts in low temperature ranges of 100°C?200°C. In the case of sucrose as a carbon source, sulfuric acid (H2SO4) is typically used as an acid catalyst for the dehydration and subsequent oligomerization of the carbon... -
Effects of phosphorus content and operating temperature on the electrochemical performance of phosphorus-doped soft carbons
Eun Hee Kim and Yongju Jung 한국탄소학회 Carbon Letters 5 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.4 7 277-281 (5 pages)
content. In addition, the influence of temperature on the electrochemical behaviors of the soft carbons was investigated in a wide temperature range of 25°C to 50°C. Surprisingly, the electrochemical properties of the pristine and P-doped soft carbons were highly sensitive to the operating temperature, unlike conventional graphite. The pristine and P-doped soft carbons exhibited significantly high discharge capacities of 470 and 522 mAh/g, respectively, at a high temperature of 50°C. -
The Effect of Pressure on the properties of Carbon/Carbon Composites during the Carbonization Process
Hyeok-Jong Joo, In-Hwan Oh 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2002, Vol.3 No.2 3 85-92 (8 pages)
탄소/탄소 복합재의 기지를 형성시키는 방법은 화학증착법이나 액상유기물질에 함침하여 열처리하는 방법이 있다. 이중에서 용융피치를 사용할 경우, 기지의 흑연화가 가능하고 고밀도 탄소/탄소 복합재 생산이 가능한 잇점이 있다. 상압에서는 핏치의 구성성분 중 비점이 낮은 저분자량 성분이 쉽게 휘발되면서 반응계로부터 제거되지만, 가압함침은 핏치의 구성성분의 비점이 상승하며 반응계 외로 방출되지 않고, 반응계에서 다방향족 성분으로 중축합을 일으켜서 고분자화되면, 결과적으로 탄화수율의 상승과 함게 함침효율을... -
The Carbonization Behaviors of Coal Tar Pitch for Mechanical Seal
Jae-Hong Chae, Kyung-Ja Kim, Kwang-Youn Cho, JAe-Young Choi 한국탄소학회 Carbon Letters 10 Pages
한국탄소학회 Carbon Letters Vol.2 No.3&4 5 182-191 (10 pages)
탄소는 상온부근에서 화화적으로 안정된 원소로 기계 및 화학공업 분야에서 용도가 다양하다. 물리적인 특성으로 탄소는 금속적 성질과 세라믹 성질을 동시에 지니고 있으며, 흑연 결정 성장 정도에 따라 분류되고 그 성장속도가 클수록 금속적 성질을 지니게 된다. 이와같이 어느 쪽의 성질이 지배적인가에 의해 물리적 성질이 다양하며 용도도 달라진다. -
Pathology of non-thermal irreversible electroporation (N-TIRE)-induced ablation of the canine brain
John H. Rossmeisl Jr., Paulo A. Garcia, John L. Roberston, Thomas L. Ellis, Rafael V. Davalos 대한수의학회 Journal of Veterinary Science 8 Pages
대한수의학회 Journal of Veterinary Science 2013, 제 14권 제 4호 9 433-440 (8 pages)
This study describes the neuropathologic features of normal canine brain ablated with non-thermal irreversible electroporation (N-TIRE). The parietal cerebral cortices of four dogs were treated with N-TIRE using a dose-escalation protocol with an additional dog receiving sham treatment. Animals were allowed to recover following N-TIRE ablation and the effects of treatment were monitored with clinical and magnetic resonance imaging examinations. Brains were subjected to histopathologic and... -
CO₂, Er:YAG, Er,Cr:YSGG 레이저를 임프란트 표면에 조사시 표면성상의 변화 및 열 변화에 관한 연구
강만석, 김현철, 이장렬 대한치과이식임플란트학회 Journal of Dental Implant Research 7 Pages
대한치과이식임플란트학회 Journal of Dental Implant Research 2005, 제 24권 2호 2 14-20 (7 pages)
임프란트 실패의 중요한 원인인 임프란트 주위염은 크게 교합력, 치태세균이나 치석의 축적 등과 같은 국 소적 요인과 전신질환이나 신체방어력의 약화 등과 같은 전신적 요인에 의해 단독적 또는 복합적으로 발 생된다. 임프란트 주위염은 임프란트 주위 치은의 염 증을 동반한 임프란트 주위골의 임상적, 방사선적인 상실을 가지는 임상적인 증상의 표현이다. -
하수슬러지의 연료 이용을 위한 최적탄화조건 연구
박민숙, 정성배, 김철규 한국열환경공학회 한국열환경공학회 학술대회지 18 Pages
한국열환경공학회 한국열환경공학회 학술대회지 2014년 춘계 30 183-200 (18 pages)
현재 배출되는 하수슬러지는 주로 탈수한 소화 및 잉여슬러지이다. 소화슬러지는 혐 기성 혹은 호기성 소화조에서 처리 후 생산된 슬러지를 말한다. 호기성 소화 슬러지는 짙은 회색을 띠며 약간 흙냄새가 나고, 혐기성 소화 슬러지는 검은색으로 타르냄새가 난다. 혐기성 소화 슬러지의 경우 고형물 함량은 2.5~7%이고, 그 중 유기물질 함량은 60%이다. 생슬러지는 침사지 및 유입펌프장을 통해 1차 침전지로 유입된 하수가 중력 또는 약품에 의한 응집침전 등에 의해 분리된 슬러지를 말하며, 1차 슬러지라고도 한 다. 도시하수의 경우... -
석탄과 EFB 반탄화물의 혼합 연소에 따른 발생가스 특성
최병수, 구재회, 임용택, 오세천 한국열환경공학회 열환경공학 9 Pages
한국열환경공학회 열환경공학 2016, 제 13권 1호 8 53-61 (9 pages)
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마이크로파 플라즈마에 의한 탄소섬유 생산 : 연속식 실험
한국열환경공학회 열환경공학 2016, 제 13권 1호 7 45-52 (8 pages)
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볏짚 이용 Bio-SRF 활용을 위한 Torrefaction 반응 특성 연구
남성방, 임용택, 구재회, 남상익, 김윤명, 오세천, Jeeban Poudel 한국열환경공학회 열환경공학 8 Pages
한국열환경공학회 열환경공학 2015, 제 12권 2호 4 25-32 (8 pages)
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종이가 주성분인 RDF(Refuse Derived Fuel)의 탄화특성
최연석, 김부웅 한국열환경공학회 열환경공학 6 Pages
한국열환경공학회 열환경공학 2005, 제 2권 2호 4 107-112 (6 pages)
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바이오메스 열처리 및 수열합성에 의한 복합기공소재 제조
서정권, 이정민 한국열환경공학회 열환경공학 16 Pages
한국열환경공학회 열환경공학 2006, 제 3권 1호 5 39-54 (16 pages)
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Pitch 열개질에 의한 탄소계 전극소재 합성
서정권, 홍지숙, 이정민, 이범재 한국열환경공학회 열환경공학 15 Pages
한국열환경공학회 열환경공학 2006, 제 3권 2호 1 93-108 (15 pages)
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Pitch 열개질에 의한 탄소계 전극소재 합성
서정권, 홍지숙, 이정민, 이범재 한국열환경공학회 열환경공학 15 Pages
한국열환경공학회 열환경공학 2009, 제 6권 1호 5 41-55 (15 pages)
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SiC 전환 카본 제거공정에 대한 CFD 해석
Poudel Jeeban, 임대원, 권우택, 오세천 한국열환경공학회 열환경공학 8 Pages
한국열환경공학회 열환경공학 2014, 제 11권 1호 6 42-49 (8 pages)
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하수슬러지의 연료 이용을 위한 최적탄화조건
박민숙, 정성배, 김철규 한국열환경공학회 열환경공학 12 Pages
한국열환경공학회 열환경공학 2015, 제 12권 1호 1 1-12 (12 pages)
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Graphitization of PAN-based carbon fibers by CO₂ laser irradiation
Liangbo Yao, Weimin Yang, Sanyang Li, Yang Sha, Jing Tan, Ying An, Haoyi Li 한국탄소학회 Carbon Letters 6 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 13 97-102 (6 pages)
Graphite fibers are materials with a high specific modulus that have attracted much interest in the aerospace industry, but their high manufacturing cost and low yield are still problems that prevent their wide applications in practice. This paper presents a laser-based process for graphitization of carbon fiber (CF) and explores the effect of laser radiation on the microstructure of CF. The obtained Raman spectra indicate that the outer surface of CF evolves from turbostratic structures into a... -
Physicochemical properties and methane adsorption performance of activated carbon nanofibers with different types of metal oxides
Faten Ermala Che Othman, Norhaniza Yusof, Hasrinah Hasbullah, Juhana Jaafar, Ahmad Fauzi Ismail, Noor Shawal Nasri 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 11 82-89 (8 pages)
In this study, composite PAN-based ACNFs embedded with MgO and MnO2 were prepared by the electrospinning method. The resultant pristine ACNFs, ACNF/MgO and ACNF/MnO2 were characterized in terms of their morphological changes, SSA, crystallinity and functional group with FESEM-EDX, the BET method, XRD and FTIR analysis, respectively. Results from this study showed that the SSA of the ACNF/MgO composite (1893 m2 g?1) is significantly higher than that of the pristine ACNFs and ACNF/MnO2 which is... -
Interconnected meso/microporous carbon derived from pumpkin seeds as an efficient electrode material for supercapacitors
Mayakrishnan Gopiraman, Somasundaram Saravanamoorthy, Seung-Hyun Kim, Ill-Min Chung 한국탄소학회 Carbon Letters 9 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 10 73-81 (9 pages)
Interconnected meso/microporous activated carbons were prepared from pumpkin seeds using a simple chemical activation method. The porous carbon materials were prepared at different temperatures (PS-600, PS-700, PS-800, and PS-900) and demonstrated huge surface areas (645?2029 m2 g?1) with excellent pore volumes (0.27?1.30 cm3 g?1). The wellcondensed graphitic structure of the prepared activated carbon materials was confirmed by Raman and X-ray diffraction analyses. The presence of heteroatoms (O... -
Relationships between dielectric properties and characteristics of impregnated and activated samples of potassium carbonate- and sodium hydroxide-modified palm kernel shell for microwave-assisted activation
Norulaina Alias, Muhammad Abbas Ahmad Zaini, Mohd Johari Kamaruddin 한국탄소학회 Carbon Letters 11 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 9 62-72 (11 pages)
at various microwave frequencies (1?6 GHz) and temperatures (25, 35, and 45°C). The results show that the dielectric properties varied with frequency, temperature, moisture content, carbon content and mass ratio of the ionic solids. PKSK1.75 (PKS impregnated with K2CO3 at a mass ratio of 1.75) and PKSN1.5 (PKS impregnated with NaOH at a mass ratio of 1.5) exhibited a high loss tangent (tan δ) indicating the effectiveness of these materials to be heated by microwaves. K2CO3 and NaOH can act as... -
Preparation of photoresist-derived carbon micropatterns by proton ion beam lithography and pyrolysis
Hui-Gyun Nam, Jin-Mook Jung, In-Tae Hwang, Junhwa Shin, Chang-Hee Jung, Jae-Hak Choi 한국탄소학회 Carbon Letters 7 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 8 55-61 (7 pages)
Carbon micropatterns (CMs) were fabricated from a negative-type SU-8 photoresist by proton ion beam lithography and pyrolysis. Well-defined negative-type SU-8 micropatterns were formed by proton ion beam lithography at the optimized fluence of 1×1015 ions cm?2 and then pyrolyzed to form CMs. The crosslinked network structures formed by proton irradiation were converted to pseudo-graphitic structures by pyrolysis. The fabricated CMs showed a good electrical conductivity of 1.58×102 S cm?1 and a... -
Improvement of gas sensing properties of carbon nanofibers based on polyacrylonitrile and pitch by steam activation
Jeongsik Kim, Hyung-Il Kim, Jumi Yun 한국탄소학회 Carbon Letters 5 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 5 36-40 (5 pages)
material. Pitch nanofibers were properly fabricated by incorporating polyacrylonitrile as an electrospinning supplement component. Polyacrylonitrile/pitch nanofibers were activated with steam at various temperatures followed by subsequent carbonization to make carbon nanofibers with a highly conductive graphitic structure. Steam activation was effective in facilitating gas adsorption onto the carbon nanofibers due to the increased surface area. The carbon nanofibers activated at 800°C had a... -
Catalytic hydrogenation-assisted preparation of melt spinnable pitches from petroleum residue for making mesophase pitch based carbon fibers
Dong Hun Lee, Jisu Choi, Young Se Oh, Yoong Ahm Kim, Kap Seung Yang, Ho Jin Ryu, Yong Jung Kim 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 4 28-35 (8 pages)
We demonstrated an effective way of preparing melt spinnable mesophase pitches via catalytic hydrogenation of petroleum residue (fluidized catalytic cracking-decant oil) and their subsequent thermal soaking. The mesophase pitches thus obtained were analyzed in terms of their viscosity, elemental composition, solubility, molecular weight, softening point and optical texture. We found that zeolite-induced catalytic hydrogenation under high hydrogen pressure contributed to a large variation in the... -
Preparation of carbon discs using petroleum-based binder pitch reformed with carbon black
Sangmin Lee, Kyung Hoon Kim, Young-Seak Lee 한국탄소학회 Carbon Letters 4 Pages
한국탄소학회 Carbon Letters 2017, Vol.23 13 84-87 (4 pages)
coal tar-based pitches and petroleum-based pitches. The raw materials of the petroleum-based pitch are obtained through petroleum refining processes, such as fluidized catalytic cracking decant oil, vacuum residue and pyrolyzed fuel oil (PFO). These residue oils are reformed to petroleum-based pitches that are solid at room temperature and for which the molecular weight is controlled through cyclization, aromatization and polymerization conducted using high-temperature heat treatment [9-13]. -
Facile fabrication of electrospun polyacrylonitrile/ poly(vinylidene fluoride)-based carbon nanofibers for supercapacitor electrodes
Hyo In Lee, Soo-Jin Park 한국탄소학회 Carbon Letters 5 Pages
한국탄소학회 Carbon Letters 2017, Vol.23 12 79-83 (5 pages)
Energy storage devices and renewable energy sources are some of the most interesting alternatives being developed to solve the energy crisis [1,2]. At the same time, energy harvesting and storage devices are among the technologies with the highest potential to efficiently satisfy the energy requirements of compact electronic devices [3]. Among various energy storage devices, supercapacitors are the among the most intensely researched because of their high power density, long cycle retention, and...
