전체 선택해제
총 88건 검색
본문검색 결과만 보기
-
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 case of the CPP, the turning point or the struc- tural ordering perpendicular to the graphene planes occurred at around 800900 oC. This temperature difference of the structural Table 7. Carbonization yield and electrical conductivity of the carbonized pitch bers Sample name Carbonization yield (%) Electrical con- ductivity (S/m) Pitch fber CPF800 81.9 1.69 × 10 4 CPF900 81.2 1.07 × 10... function of 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... -
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)
compared with the other acid catalysts in- cluding sulfuric acid, hydrochloric acid, nitric acid and acetic acid. These results may be attributed to the stability of the acid catalysts during the carbonization rather than the acidity strength. p-toluene sulfuric acid and phosphoric acid yield ordered mesoporous carbon materials by the double role as a carbon precursor and an acid catalyst for... 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 precursor. This is very important for preventing the infiltrated carbon precursors from draining outside the mesopores of the silica templates before... -
Effects of heat treatment time on aromatic yield of pyrolysis fuel oil-derived pitches
Hye Kyoung Shin, Min-Kang Seo, Yun Hyuk Bang, Soo-Jin Park 한국탄소학회 Carbon Letters 3 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 13 104-106 (3 pages)
Oshida K, Bonnamy S. Primary carbonization of an anisotro- pic ‘mesophase’ pitch compared to conventional isotropic pitch. Carbon, 40, 2699 (2002). http://dx.doi.org/10.1016/s0008- 6223(02)00184-7. [9] Lee S, Eom Y, Kim BJ, Mochida I, Yoon SH, Kim BC. The ther- motropic liquid crystalline behavior of mesophase pitches with dif- ferent chemical structures. Carbon, 81, 694 (2015). http://dx.doi.... -
Yield enhancement of matrix precursor in short carbon fiber reinforced randomly oriented carbon/carbon composite
Thakur Sudesh Kumar Raunija, Sharad Chandra Sharma, Anil Verma 한국탄소학회 Carbon Letters 9 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 7 57-65 (9 pages)
the compact after carbonization (g), yr = yield rate (%/h), yi = yield impact (%), pt = total process time (h), ro = obtained density after carbonization (g/cm 3), ra = theoretical density of the compact (g/cm 3), which was calculated based upon the practically possible density of the carbon matrix obtained from SP at carbonization temperature and quoted density of carbon fbers in supplier’s... system was studied. The fourier transform infrared spectrometry (FTIR), thermogravimetric analysis (TGA), yield, yield rate, and yield impact were used to check the effect of stabilization and pressure on the yield of the matrix precursor and the end properties of the composite thereafter. The results showed that the yield increased with stabilization duration up to 20 h whereas it decreased for stabilization duration beyond 20 h. Further results showed that the stabilized matrix precursor for a... -
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)
a key parameter which may infuence the fnal pore-size distribu- tion [15]. Carbonization temperature is another variable which has a large effect on pore- volume evolution [15-17]. High carbonization temperature results in a greater amount of volatiles being released from the raw material, and eventually infuences the product yield DOI: http://dx.doi.org/ DOI:10.5714/CL.2014.15.2.146 This is an... In this work, activated carbon nanofiber (ACNF) electrodes with high double-layer capacitance and good rate capability were prepared from polyacrylonitrile nanofibers by optimizing the carbonization temperature prior to H2O activation. The morphology of the ACNFs was observed by scanning electron microscopy. The elemental composition was determined by analysis of X-ray photoelectron spectroscopy. N2-adsorption-isotherm characteristics at 77 K were confirmed by Brunauer-Emmett-Teller and... -
Vertically Aligned Carbon Film Synthesized from Magnetically Oriented Polyacetylene using Morphology Retaining Carbonization
Munju Goh, Yong Mun Choi 한국탄소학회 Carbon Letters 4 Pages
한국탄소학회 Carbon Letters 2012, Vol.13 No.4 5 226-229 (4 pages)
the carbon flm after carbonization was less than 1.0 wt%. The carbonization yield of the carbon flm is about 7090% of the weight of the PA flm. Fig. 4 provides SEM images of the vertically aligned carbon flms prepared by carbonization of iodine-doped PA flm. Interestingly, the vertically aligned morphology of the PA flm was maintained after carbonization. The fbril length of the carbon flm... -
Effect of carbonization temperature and chemical pre-treatment on the thermal change and fiber morphology of kenafbased carbon fibers
JinMyungKim, InSeongSong, DonghwanCho, IkpyoHong 한국탄소학회 Carbon Letters 7 Pages
한국탄소학회 Carbon Letters 2011, Vol.12 No.3 2 131-137 (7 pages)
shrinkage of kenaf fbers oc- curred in the carbonization furnace and the thermal stability was increased with the increase of the carbonization temperature from 700 oC to 1100 oC. 2. NaOH pre-treatment was useful for reducing the weight loss and the longitudinal shrinkage of kenaf fbers in the car- bonization furnace and also for increasing the product yield of kenaf-based carbon fbers. A... -
Pressure Effects on the Morpfology Development of C/C Composites During Carbonization
Hyeok Jong Joo, Seung Hee Ryu and Hun SEung Ha 한국탄소학회 Carbon Letters 7 Pages
한국탄소학회 Carbon Letters Vol.1 No.3&4 8 158-164 (7 pages)
Carbon/carbon Composites, Cokes, Pressure Carbonization, Mesophase, Pitch 1. / (carbon/carbon composite; C/C) . 2500 oC , [1, 2]. / , pseudo-plastic [3, 4]. . / . / (unidirectional; UD), 2 (two-directional; 2D), 3 (three-directional; 3D) (multi-directional; nD) . (anisotropic) (isotropic) . , z UD 2D (delamination) [5-7]. 3D nD [8]. (precursor) (carbon yield) , . / . / (densi- fication) [9]. /... -
열중량분석법을 이용한 하수슬러지 탄화물의 연소특성 평가
박소미, 임혁, 김철규 한국열환경공학회 한국열환경공학회 학술대회지 10 Pages
한국열환경공학회 한국열환경공학회 학술대회지 2015년 추계 3 16-25 (10 pages)
0.19 0.69 Calorific value (kcal/kg) dried 3,875 3,400 carbonized 3,098 3,216 Carbonization Yield (wt%) 61.3 71.1 TGA 그래프에서는 E.S와 D.S 모두 승온속도가 증가함에 따라 전체적으로 온도범위 가 고온쪽으로 넓어지는 경향을 확인할 수 있다. DTG 그래프에서는 E.S는 2개의 peak 가 D.S는 1개의 peak로 두 슬러지간의 연소특성이 다르게 나타났다. E.S의 DTG 그래프 에서 최대 peak는 500~550℃(5℃/min, 10℃/min)와...