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Real time observation of mouse fetal skeleton using a high resolution X-ray synchrotron
Dong Woo Chang, Bora Kim, Jae Hoon Shin, Young Min Yun, Jung Ho Je, Yeu kuang Hwu, Jung Hee Yoon, Je Kyung Seong 대한수의학회 Journal of Veterinary Science 8 Pages
대한수의학회 Journal of Veterinary Science 2011, 제 12권 제 2호 1 107-114 (8 pages)
A non-monochromatized X-ray synchrotron (white beam, 5C1 beamline) was employed to observe the skeleton of mice under anesthesia at embryonic day (E)12, E14, E15, and E18. At the same time, conventional radiography and mammography were used to compare with X-ray synchrotron. After synchrotron radiation, each mouse was sacrificed and stained with Alizarin red S and Alcian blue to observe bony structures. Synchrotron radiation enabled us to view the mouse fetal skeleton beginning at gestation.... -
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... -
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... -
Effects of synthesis pressure conditions on the preparation of graphene-like carbonaceous materials from organic liquid precursors by a solvothermal method
Kwan-Woo Kim, Byoung Suhk Kim, Sang Won Lee, Dong Chul Chung, Byung-Joo Kim 한국탄소학회 Carbon Letters 5 Pages
한국탄소학회 Carbon Letters 2017, Vol.23 11 74-78 (5 pages)
Carbon materials with at least one dimension of 1?100 nm are called carbon nanomaterials. A significant body of previous research in physics, chemistry and biology has demonstrated that the properties of nano-composites are significantly different than those of the bulk materials [1]. Some unique phenomena, such as the quantum tunneling effect, and surface effects, have also been observed, and attributed to the large surface area and small size of the carbon nanomaterials. It has been reported... -
Electrochemical determination of chloramphenicol using a glassy carbon electrode modified with dendrite-like Fe₃O₄ nanoparticles
Krishnan Giribabu, Sung-Chan Jang, Yuvaraj Haldorai, Muruganantham Rethinasabapathy, Seo Yeong Oh, Arunkumar Rengaraj, Young-Kyu Han 한국탄소학회 Carbon Letters 10 Pages
한국탄소학회 Carbon Letters 2017, Vol.23 6 38-47 (10 pages)
In this study, magnetite (Fe3O4) nanoparticles were electrochemically synthesized in an aqueous electrolyte at a given potential of -1.3 V for 180 s. Scanning electron microscopy revealed that dendrite-like Fe3O4 nanoparticles with a mean size of < 80 nm were electrodeposited on a glassy carbon electrode (GCE). The Fe3O4/GCE was utilized for sensing chloramphenicol (CAP) by cyclic voltammetry and square wave voltammetry. A reduction peak of CAP at the Fe3O4/GCE was observed at 0.62 V, whereas... -
Extraction and characterization of lignin from black liquor and preparation of biomass-based activated carbon therefrom
Daeyeon Kim, Jinsil Cheon, Jeonghoon Kim, Daekyun Hwang, Ikpyo Hong, Oh Hyeong Kwon, Won Ho Park, Donghwan Cho 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2017, Vol.22 14 81-88 (8 pages)
In the present study, biomass-based lignin was extracted from industrial waste black liquor and the extracted lignin was characterized by means of attenuated total reflectance- Fourier transform infrared spectroscopy and 1H-nuclear magnetic resonance spectroscopy. The extracted lignin was carbonized at different temperatures and then activated with steam at 850oC. The extracted lignin in powder state was transformed into a bulky carbonized lignin due to possible fusion between the lignin... -
High-energy-density activated carbon electrode for organic electric-double-layer-capacitor using carbonized petroleum pitch
Poo Reum Choi, Sang-Gil Kim, Ji Chul Jung, Myung-Soo Kim 한국탄소학회 Carbon Letters 11 Pages
한국탄소학회 Carbon Letters 2017, Vol.22 8 70-80 (11 pages)
Activated carbons (ACs) have been used as electrode materials of electric double-layer capacitors (EDLC) due to their high specific surface areas (SSA), stability, and ecological advantages. In order to make high-energy-density ACs for EDLC, petroleum pitch (PP) precarbonized at 500?1000°C in N2 gas for 1 h was used as the electrode material of the EDLC after KOH activation. As the pre-carbonization temperature increased, the SSA, pore volume and gravimetric capacitance tended to decrease, but... -
Thermo-electrical properties of randomly oriented carbon/carbon composite
Thakur Sudesh Kumar Raunija, N. Supriya 한국탄소학회 Carbon Letters 11 Pages
한국탄소학회 Carbon Letters 2017, Vol.22 3 25-35 (11 pages)
The aim of the work was to investigate the thermo-electrical properties of low cost and rapidly produced randomly oriented carbon/carbon (C/C) composite. The composite body was fabricated by combining the high-pressure hot-pressing (HP) method with the lowpressure impregnation thermosetting carbonization (ITC) method. After the ITC method step selected samples were graphitized at 3000°C. Detailed characterization of the samples’ physical properties and thermal properties, including thermal... -
Microstructural changes of polyacrylonitrile-based carbon fibers (T300 and T700) due to isothermal oxidation (1): focusing on morphological changes using scanning electron microscopy
Seong-Moon Oh, Sang-Min Lee, Dong-Su Kang, Jae-Seung Roh 한국탄소학회 Carbon Letters 6 Pages
한국탄소학회 Carbon Letters 2016, Vol.18 3 18-23 (6 pages)
Polyacrylonitrile (PAN)-based carbon fibers have high specific strength, elastic modulus, thermal resistance, and thermal conductivity. Due to these properties, they have been increasingly widely used in various spheres including leisure, aviation, aerospace, military, and energy applications. However, if exposed to air at high temperatures, they are oxidized, thus weakening the properties of carbon fibers and carbon composite materials. As such, it is important to understand the oxidation... -
One-step synthesis of dual-transition metal substitution on ionic liquid based N-doped mesoporous carbon for oxygen reduction reaction
Ulziidelger Byambasuren, Yukwon Jeon, Dorjgotov Altansukh, Yunseong Ji, Yong-Gun Shul 한국탄소학회 Carbon Letters 12 Pages
한국탄소학회 Carbon Letters 2016, Vol.17 No.1 8 53-64 (12 pages)
promoted by the dual transition metals of iron and cobalt (Fe, Co), which were incorporated into the N-doped carbons lattice by subsequently heat treatments. All the prepared carbons were characterized by via transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). To evaluate the activities of synthesized doped carbons, linear sweep was recorded in an acidic solution to compare the ORR catalytic activities values for the use in the PEMFC syste... -
Effects of cross-linking methods for polyethylene-based carbon fibers: review
Kwan-Woo Kim, Hye-Min Lee, Jeong-Hun An, Byoung-Suhk Kim, Byung-Gak Min, Shin-Jae Kang, Kay-Hyeok An, Byung-Joo Kim 한국탄소학회 Carbon Letters 24 Pages
한국탄소학회 Carbon Letters 2015, Vol.16 No.3 2 147-170 (24 pages)
In recent decades, there has been an increasing interest in the use of carbon fiber reinforced plastic (CFRP) in aerospace, renewable energy and other industries, due to its low weight and relatively good mechanical properties compared with traditional metals. However, due to the high cost of petroleum-based precursors and their associated processing costs, CF remains a specialty product and as such has been limited to use in high-end aerospace, sporting goods, automotive, and specialist... -
Carbon-allotropes: synthesis methods, applications and future perspectives
P. S. Karthik, A. L. Himaja and Surya Prakash Singh 한국탄소학회 Carbon Letters 19 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.4 1 219-237 (19 pages)
The element carbon has been used as a source of energy for the past few hundred years, and now in this era of technology, carbon has played a significant and very prominent role in almost all fields of science and technology. So as an honour to this marvellous element, we humans should know about its various forms of existence. In this review article, we shed light on all possible carbon-allotropes; similarities in their synthesis techniques and the starting materials; their wide range of... -
Study on electrochemical performances of sulfur-containing graphene nanosheets electrodes for lithium-sulfur cells
Ki-Soo Son, Seok Kim 한국탄소학회 Carbon Letters 4 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.2 7 113-116 (4 pages)
composites were examined using scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The electrochemical properties were also characterized using cyclic voltammetry (CV). The CV data revealed that the GNS/S composites exhibited enhanced specific-current density and ~10% higher capacity, in comparison with the S-containing, activated-carbon samples. The composite electrode also showed better cycling performance for multiple charge/discharge cycles. The improvement... -
열 화학적 환원 처리를 이용한 절연체 12CaO·7Al2O3의 전도체로의 전환
정준호, 은종원, 오동근, 김광진, 홍태의, 정성민, 최봉근, 심광보, Chung. Jun-Ho, Eun. Jong-Won, Oh. Dong-Keun, Kim. Kwang-Jin, Hong. Tae-Ui, Jeong. Seong-Min, Choe. Bon 한국결정성장학회 한국결정성장학회지 7 Pages
한국결정성장학회 한국결정성장학회지 2010, Vol.20 No.4 178-184 (7 pages)
시 온도에 따른 반응 분석을 위하여 X-ray diffraction(XRD) 및 TG-DSC 분석을 시행하였다. 또한, 후 열처리 후 C12A7 cage 내부의 자유산소 이온이 수소 이온으로 치환되었는지 확인하기 위하여 TG-MS 분석을 시행하였고, $289.5^{circ}C$에서 H와 $H_2$ 가스가 방출되는 것이 확인되었으므로, H 이온이 cage 내부로 치환된 것을 확인시켜준다. 성공적으로 치환된 C12A7:H 를 홀 측정기(Hall measurement)를 이용하여 전도성을 측정하여 본 결과 $1000^{circ}C$, Ar/H=8:2의 분위기에서 8h 이상 처리된 C12A7:H의 경우 상온(300 K)에서... -
Hydrogen storage capacity of highly porous carbons synthesized from biomass-derived aerogels
Yong-Ki Choi, Soo-Jin Park 한국탄소학회 Carbon Letters 5 Pages
한국탄소학회 Carbon Letters 2015, Vol.16 No.2 9 127-131 (5 pages)
to enhance the specific surface area and microporosity. The micro-structural properties and morphologies were measured by X-ray diffraction and scanning electron microscopy, respectively. The specific surface area and microporosity were investigated by N2/77 K adsorption-desorption isotherms using the Brunauer-Emmett-Teller method and Barrett-Joyner-Halenda equation, respectively. Hydrogen storage capacity was dependent on the activation temperature. The highest capacity of 2.7 wt% at 77 K and 1... -
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)
of X-ray photoelectron spectroscopy. N2-adsorption-isotherm characteristics at 77 K were confirmed by Brunauer-Emmett-Teller and Dubinin-Radushkevich equations. ACNFs processed at different carbonization temperatures were applied 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... -
Double-walled carbon nanotubes: synthesis, structural characterization, and application
Yoong Ahm Kim, Kap-Seung Yang, Hiroyuki Muramatsu, Takuya Hayashi, Morinobu Endo, Mauricio Terrones, Mildred S. Dresselhaus 한국탄소학회 Carbon Letters 12 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.2 4 77-88 (12 pages)
Double walled carbon nanotubes (DWCNTs) are considered an ideal model for studying the coupling interactions between different concentric shells in multi-walled CNTs. Due to their intrinsic coaxial structures they are mechanically, thermally, and structurally more stable than single walled CNTs. Geometrically, owing to the buffer-like function of the outer tubes in DWCNTs, the inner tubes exhibit exciting transport and optical properties that lend them promise in the fabrication of field-effect... -
Effects of pore structures on electrochemical behaviors of polyacrylonitrile-based activated carbon nanofibers by carbon dioxide activation
Hye-Min Lee, Hong-Gun Kim, Kay-Hyeok An, Byung-Joo Kim 한국탄소학회 Carbon Letters 6 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.1 10 71-76 (6 pages)
characteristics of the ACNF were observed by scanning electron microscopy and X-ray diffraction, respectively. N2 adsorption isotherm characteristics at 77 K were confirmed by Brunauer-Emmett-Teller and Dubinin-Radushkevich equations. As experimental results, many holes or cavernous structures were found on the fiber surfaces after the CO2 activation as confirmed by scanning electron microscopy analysis. Specific surface areas and pore volumes of the prepared ACNFs were enhanced within a range... -
Ultrasonographic and macroscopic comparison of the thickness of the capsule, corium, and soft tissues in bovine claws: an in vitro study
Goksen Cecen, Hakan Salci, Deniz Seyrek Intas, Nureddin Celimli, Gulsum Ulke Caliskan 대한수의학회 Journal of Veterinary Science 6 Pages
대한수의학회 Journal of Veterinary Science 2015, 제 16권 제 1호 14 107-112 (6 pages)
15 healthy Holstein bovines were obtained. After cleaning the claws, ultrasonographic measurement of the capsule, corium, and soft tissues was performed while submerging the claws in a water bath. Macroscopic measurements were taken after cutting of the claws axially. These values were compared statistically. According to the macroscopic measurements, the mean thickness ± standard deviation (SD) of the capsule for dorsal wall and sole was 6.2 ± 0.1 and 9.5 ± 0.4 mm,... -
Comparing the osteogenic potential of canine mesenchymal stem cells derived from adipose tissues, bone marrow, umbilical cord blood, and Wharton's jelly for treating bone defects
Byung-Jae Kang, Hak-Hyun Ryu, Sung Su Park, Yoshihisa Koyama, Masanori Kikuchi, Heung-Myong Woo, Wan Hee Kim, Oh-Kyeong Kweon* 대한수의학회 Journal of Veterinary Science 12 Pages
대한수의학회 Journal of Veterinary Science 2012, 제 13권 제 3호 12 299-310 (12 pages)
Alternative sources of mesenchymal stem cells (MSCs) for replacing bone marrow (BM) have been extensively investigated in the field of bone tissue engineering. The purpose of this study was to compare the osteogenic potential of canine MSCs derived from adipose tissue (AT), BM, umbilical cord blood (UCB), and Wharton's jelly (WJ) using in vitro culture techniques and in vivo orthotopic implantation assays. After canine MSCs were isolated from various tissues, the proliferation and osteogenic... -
남한산성 외성 여장 사춤재와 현대 사춤재의 비교 연구
김은경, 강소영, 안선아, 남병직 한국대학박물관협회 고문화 17 Pages
한국대학박물관협회 고문화 2018, 제92집 3 61-77 (17 pages)
본 연구에서는 석회가 전통 방법으로 사용된 남한산성 봉암성 여장 사춤재와 현대의 시공법으로 보수한 원성 여장 사춤재의 재료적 특성을 비교·분석하였다. 여장 사춤재의 주구성광물을 분석한 결과, 전통 석회류가 사용된 봉암성 여장 시료는 밝은 연주홍색의 기질에 석영, 장석, 운모, 휘석, 불투명 광물이 혼합되어 있었으며, 원성 여장에서는 봉암성 여장에 비해 석영과 장석의 비율이 높으며 석고와백운석이 특이적으로 검출되었다. 시료의 주요 화학 성분을 분석한 결과 석회의 주성분인 Ca는 봉암성여장에서 11.15-15.17 wt%,...
