• 자원리싸이클링
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• 제10권4호
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• pp.18-23
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• 2001

페놀을 함유한 폐 활성탄의 가열 재생시 대기 오염물인 페놀이 생성되어 환경을 오염시키므로 발생하는 페놀 제거에 대한 검토가 필요하다 본 연구에서 실험에 사용하여 페놀을 함유한 S.회사 활성탄(WS-GAC), C.회사 활성탄(WC-GAC), L.회사 활성탄(UL-GAC)의 전해산화는 정전위 전해방식으로 실험하였다. 시료에 함유된 페놀농도는 100 rng/g, 지지 전해질은 1.0% 염화나트륨 용액, Ti-Ir(10$\times$10$ extrm{cm}^2$)전극 간격은 2 cm,전류밀도는 $1.25 A/dm^2$인 조건에서 실험이 이루워졌을 경우 전해 산화 실험에서 얻은 결과 페놀의 잔류물은 검출되지 않았다. 그러므로 전해산화 반응에서 빈응시간, 전류밀도, 지지전해질의 농도, 전극간의 거리가 60 minutes, 1.25 $A/dm^2$, 1.0%, 2 cm 임을 알 수 있었다.

• 전기화학회지
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• 제17권3호
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• pp.179-186
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• 2014

Methanol electro oxidation on the surface of carbon paste modified by $NiCl_2/6H_2O$ was studied in 1M NaOH by potentiostatic and potentiodynamic methods. Ni/C catalyst by the concentration of 5% Ni showed about twice higher electro catalytic activity than Ni metal. The amount of monolayer's on the surface of electrode is almost one order higher for Ni/C than Ni electrode. The kinetic parameters and the diffusion coefficient of methanol were derived from chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements.

• 한국표면공학회지
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• 제29권6호
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• pp.773-780
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• 1996

Silicon oxide films were prepared by using five kinds of organosilicon compound as gas sources without oxygen by rf plasma-enhanced CVD (PECVD). UV light was irradiated on a substrate vertically during deposition to enhance film oxidation and ablation of carbon contamination in a deposited films. Films prepared with UV irradiation contained less carbon than those prepared without UV irradiation. The oxidation of the films was improved by UN irradiation. The effect of UV irradiation was, however, not observed when the films were prepared with tetramethy lsilane (TMS) which contained no oxygen atom. Dissociated oxygen atoms from an organosilicon compound were excited in the plasma with UV irradiation around the substrate surface and affected the enhancement of film oxidation and ablation of carbon in the films.

• Bulletin of the Korean Chemical Society
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• 제5권1호
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• pp.41-44
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• 1984

The oxidation of carbon monoxide has been investigated on Ni-doped ${\alpha}-Fe_2O_3$ catalyst at 300 to $450^{\circ}$. The oxidation rates have been correlated with 1.5-order kinetics; first with respect to CO and 1/2 with respect to $O_2$. Carbon monoxide is adsorbed on lattice oxygen of Ni-doped ${\alpha}-Fe_2O_3$, while oxygen appears to be adsorbed on oxygen vacancy formed by Ni-doping. The conductivities show that adsorption of CO on O-lattice produces conduction electron and adsorption of $O_2$ on O-vacancy withdraws the conduction electron from vacancy. The adsorption process of CO on O-lattice is rate-determining step and dominant defect of Ni-doped ${\alpha}-Fe_2O_3$ is suggested from the agreement between kinetic and conductivity data.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.266-266
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• 2012

Ni films with a thickness of 700-800 nm were deposited on carbon fiber layers using electroless deposition, and surface structures and chemical properties of these films with various annealing temperatures (300, 600 and $900^{\circ}C$) were studied. $600^{\circ}C$-annealing under atmospheric conditions resulted in formation of porous surface structures with a mean pore size of ~100 nm, whereas the other samples showed non-porous surface structures. $600^{\circ}C$-annealed Ni film showed much higher reactivities for toluene adsorption and CO oxidation comparing to other non-porous surfaces.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.330-331
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• 2005

It was found possible to evaluate the temperature at which major scale failure takes place during cooling by installing a most modem acoustic emission(AE) analytical system. Ultra low carbon steel and low carbon steels containing a few minor alloying elements were oxidized in air at 900, 1050 and $1200^{\circ}C$ for 20 min, and then cooled in vacuum at 30, 70 and $110^{\circ}C/min$. The significance of the present research is the evaluation of the spallation temperature and thus the calculation of apparent thermal stress for scale spallation using the difference between oxidation temperature and spallation temperature. They were assessed as 0.22 to 0.68, 0.45 to 1.80, and 0.65 to 1.95 GPa for oxidation at 900, 1050 and $1200^{\circ}C$, respectively.

• 미생물학회지
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• 제24권1호
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• pp.46-50
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• 1986

일산화탄소를 유일한 탄소 및 에너지원으로 이용하여 성장한 Acinetobacter sp. 1의 일산화탄소 산화를 전자전달계를 조사하였다. 이 세균은 a, b, c, 그리고 o형의 사이토크롬을 소유하고 있었고, UQ 10은 이 세균의 생리적인 전자수용제로 작용할 수 없음이 밝혀졌다. 이 세균에 존재하는 사이토크롬들 중에서 b와 o는 일산화탄소 산화와 연관되어 있으나 a와 c는 관계가 없었으며, NAD(P)도 이 세균의 일산화탄소 산화와 무관한 것으로 밝혀졌다.

• Carbon letters
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• 제10권3호
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• pp.239-249
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• 2009

• Carbon letters
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• 제4권3호
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• pp.133-139
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• 2003

Carbon/carbon composites are ideal candidates for a number of aerospace applications including structural materials for advanced vehicles, leading edges, structures of re-entry and hypersonic vehicles and propulsion systems. One serious defect for such application of the carbon/carbon composites is their poor oxidation resistance in high temperature oxidizing environments. SiC coating was employed to protect the composites from oxidation. It is mechanically and chemically stable under extreme thermal and oxidative environments, provides good adhesion to the substrate, and offers good thermal shock resistance. The SiC layer on the nozzle machined from the carbon/carbon composites was formed by pack-cementation method. Then, erosion characteristic of SiC coated carbon/carbon nozzle was examined by combustion test using a liquid rocket motor. The erosion rates were measured as function of combustion pressure, ratio of oxygen to fuel, combustion time, density of the composites and geometry of reinforced carbon fibre in the composites. The morphology change of the composites after combustion test was investigated using SEM and erosion mechanism also was discussed.

• Carbon letters
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• 제3권3호
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• pp.127-132
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• 2002

Unidirectional polymer composites were prepared using high-strength carbon fibers as reinforcement and phenolic resin as matrix precursor with keeping fiber volume fraction at 30, 40, 50 and 60% respectively. These composites were carbonized at $1000^{\circ}C$ and graphitised at $2600^{\circ}C$ in the inert atmosphere. The carbonized and graphitised composites were characterized for mechanical properties as well as microstructure. Microscopic studies were carried out of the polished surface of carbonized and graphitised composites after etching by chromic acid, to understand the effect of fiber volume fraction on oxidation at fiber-matrix interface. It is found that the flexural strength in polymer composites increases with fiber volume fraction and so does for the carbonised composites. However, the trend was found to be reversed in graphitised composites. In all the carbonized composites anisotropic region has been observed at fiber-matrix interface which transforms into columnar type microstructure upon graphitisation. The extension of strong and weak columnar type microstructure is function of fiber volume fraction. SEM microscopy of the etched surface of the sample reveal that composites containing 40% fiber volume has minimum oxidation at the interface, revealing a strong interfacial bonding.