전체 선택해제
총 33건 검색
본문검색 결과만 보기
-
The Japanese Hands-Off Approach to Curriculum Guidelines for Early Childhood Education as a Form of Cultural Practice
Akiko Hayashi 환태평양유아교육연구학회 Asia-Pacific journal of research in early childhood education 17 Pages
환태평양유아교육연구학회 Asia-Pacific journal of research in early childhood education 2011, Vol.5 No.2 6 107-123 (17 pages)
This paper explores the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) approach to curriculum policy in early childhood education. The Kindergarten Curriculum Guideline contains few directives or practical suggestions for teachers. The abstractness and indirectness of the MEXT approach to establishing curricular guidelines stands in stark contrast to the much more explicit and directive curriculum guidelines for early childhood education found in China, the US,... -
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)
The aim of this work was to evaluate the dielectric properties of impregnated and activated palm kernel shells (PKSs) samples using two activating agents, potassium carbonate (K2CO3) and sodium hydroxide (NaOH), at three impregnation ratios. The materials were characterized by moisture content, carbon content, ash content, thermal profile and functional groups. The dielectric properties were examined using an open-ended coaxial probe method at various microwave frequencies (1?6 GHz) and... -
Study on properties of eco-friendly reduction agents for the reduced graphene oxide method
Young-il Na, Young Il Song, Sun Woo Kim, Su-Jeong Suh 한국탄소학회 Carbon Letters 9 Pages
한국탄소학회 Carbon Letters 2017, Vol.24 1 1-9 (9 pages)
We studied the basic properties and fabrication of reduced graphene oxide (rGO) prepared using eco-friendly reduction agents in the graphene solution process. Hydrazine is generally used to reduce graphene oxide (GO), which results in polluting emissions as well as fixed nitrogen functional groups on different defects in the graphene sheets. To replace hydrazine, we developed eco-friendly reduction agents with similar or better reducing properties, and selected of them for further analysis. In... -
Synthesis and characterization of carbon doped TiO₂ photocatalysts supported on stainless steel mesh by sol-gel method
JO. Tijani, OO. Fatoba, TC. Totito, WD. Roos, LF. Petrik 한국탄소학회 Carbon Letters 12 Pages
한국탄소학회 Carbon Letters 2017, Vol.22 6 48-59 (12 pages)
This study synthesized pure anatase carbon doped TiO₂ photocatalysts supported on a stainless steel mesh using a sol-gel solution of 8% polyacrylonitrile (PAN)/dimethylformamide (DMF)/TiCl₄. The influence of the pyrolysis temperature and holding time on the morphological characteristics, particle sizes and surface area of the prepared catalyst was investigated. The prepared catalysts were characterized by several analytical methods: high resolution scanning electron microscopy (HRSEM), energy... -
Study of complex electrodeposited thin film with multi-layer graphene-coated metal nanoparticles
Young-Lae Cho, Jung-woo Lee, Chan Park, Young-il Song, Su-Jeong Suh 한국탄소학회 Carbon Letters 6 Pages
한국탄소학회 Carbon Letters 2017, Vol.21 8 68-73 (6 pages)
We have demonstrated the production of thin films containing multilayer graphene-coated copper nanoparticles (MGCNs) by a commercial electrodeposition method. The MGCNs were produced by electrical wire explosion, an easily applied technique for creating hybrid metal nanoparticles. The nanoparticles had average diameters of 10?120 nm and quasispherical morphologies. We made a complex-electrodeposited copper thin film (CETF) with a thickness of 4.8 μm by adding 300 ppm MGCNs to the electrolyte... -
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)
Isotropic pitch-based fibers produced from coal tar pitch with the melt-blowing method were carbonized at temperatures ranging from 800 to 1600oC to investigate their crystalline structure and physical properties as a 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... -
Morphologies and surface properties of cellulose-based activated carbon nanoplates
Seulbee Lee, Min Eui Lee, Min Yeong Song, Se Youn Cho, Young Soo Yun, Hyoung-Joon Jin 한국탄소학회 Carbon Letters 7 Pages
한국탄소학회 Carbon Letters 2016, Vol.20 5 32-38 (7 pages)
In this study, cellulose nanoplates (CNPs) were fabricated using cellulose nanocrystals obtained from commercial microcrystalline cellulose (MCC). Their pyrolysis behavior and the characteristics of the product carbonaceous materials were investigated. CNPs showed a relatively high char yield when compared with MCC due to sulfate functional groups introduced during the manufacturing process. In addition, pyrolyzed CNPs (CCNPs) showed more effective chemical activation behavior compared with... -
Waste coffee grounds-derived nanoporous carbon nanosheets for supercapacitors
Min Hong Park, Young Soo Yun, Se Youn Cho, Na Rae Kim, Hyoung-Joon Jin 한국탄소학회 Carbon Letters 6 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 8 66-71 (6 pages)
The development of nanostructured functional materials derived from biomass and/or waste is of growing importance for creating sustainable energy-storage systems. In this study, nanoporous carbonaceous materials containing numerous heteroatoms were fabricated from waste coffee grounds using a top-down process via simple heating with KOH. The nanoporous carbon nanosheets exhibited notable material properties such as high specific surface area (1960.1 m2 g?1), numerous redox-active heteroatoms... -
Effect of fiber-matrix adhesion on the fracture behavior of a carbon fiber reinforced thermoplastic-modified epoxy matrix
H.J. Carrillo-Escalante, A. ?lvarez-Castillo, A. Valadez-Gonz?lez, P. J. Herrera-Franco 한국탄소학회 Carbon Letters 10 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 6 47-56 (10 pages)
In this study, the fracture behavior of a thermoplastic-modified epoxy resin reinforced with continuous carbon fibers for two levels of fiber-matrix adhesion was performed. A carbon fiber with commercial sizing was used and also treated with a known silane, (3-glycidoxy propyl trimethoxysilane) coupling agent. Toughness was determined using the double cantilever test, together with surface analysis after failure using scanning electron microscope. The presence of polysulfone particles improved... -
Modifications of mechanical, thermal, and electrical characteristics of epoxy through dispersion of multi-walled carbon nanotubes in supercritical carbon dioxide
MGH ZAIDI, Sanjeev Joshi, Manoj Kumar, Deepak Sharma, Ashwin Kumar, Sarfaraz Alam, Prakash Sah 한국탄소학회 Carbon Letters 10 Pages
한국탄소학회 Carbon Letters 2013, Vol.14 No.4 4 218-227 (10 pages)
