• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.638-644
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• 2017

Pitch based activated carbon fibers for electric double layer capacitor (EDLC) electrodes were treated by oxyfluorination via varying the ratio of fluorine and oxygen gases to improve high power property. As the partial pressure of fluorine increased, the oxyfluorinated activated carbon fibers showed an increase of linear fluorine functional groups. While the oxygen functional groups increased, no changes was observed with respect to the partial gas pressure. The specific surface area and pore volume decreased due to the etching reaction on the activated carbon fiber surface through oxyfluorination, but the mesopore volume increased about 4.5 times. In the case of activated carbon fibers treated with 50% of the fluorine gas partial pressure, the specific capacitance increased to about 29% and 61% at scan rates of 5 and 50 mV/s, respectively. The improvement of the specific capacitance was believed to be due to the introduction of oxygen and fluorine functional groups on the activated carbon fiber surface and the increase of mesopores through oxyfluorination.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2010.04a
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• pp.147-155
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• 2010

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1986.11a
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• pp.29-41
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• 1986

마찰계수는 서로 접촉하여 운동하는 두 물체간의 특성으로 간주되며 일반적으로 상대속도나 작용하중에 별로 영향을 받지 않는 것으로 알려져 있다. 화학적으로나 물리적으로 오염되지 않은 깨끗한 금속간의 마찰실험의 경우, 이 실험이 불활성 가스나 진공내에서 행해질 경우 상당히 큰 마찰저항을 경험하게 되나, 공기중에서의 실험에서는 작은 마찰저항이 기록되어 산화막이나 다른 오염물에 의해 형성된 막이 마찰저항을 감소시킨다고 보고 있다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.05a
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• pp.137-138
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• 2011

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.05a
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• pp.85-86
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• 2016

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.10a
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• pp.129-130
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• 2016

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.05a
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• pp.95-96
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• 2016

• Fire Science and Engineering
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• v.17 no.2
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• pp.43-49
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• 2003

For the inert gases of Ar, $N_2$and $CO_2$, the empirical equations of the gas mixture were correlated in terms of saturated pressure, density and viscosity. They were obtained by regression analysis based on the mixing rule. The empirical equation of saturated pressure was assumed as the first order function of temperature. The empirical form of density was expressed as compressibility factor and saturated pressure while the empirical equation of viscosity was formulated as a power function of temperature. This empirical equations of the physical properties were obtained in the composition of Ar, $N_2$and $CO_2$, 40/50/10(mol. %).

• Journal of Conservation Science
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• v.27 no.2
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• pp.231-241
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• 2011

Anoxia Treatment using inert gas like nitrogen and argon has been used to eradicate insects successfully in museums as alternative of methyl bromide and toxic insecticide. Killing efficacy of insect for anoxia treatment is depend on species of insects, oxygen concentration, temperature, relative humidity and gas. It is possible to kill museum insects which are most tolerant in anoxia environment, within 1 month below 0.03% of oxygen concentration in temperature $15{\sim}25^{\circ}C$ and relative humidity 40~60% of museum environment. And various systems like bag, tent, bubble and chamber depending on size and quantity of objects, are used.

• Journal of the Korean Vacuum Society
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• v.11 no.2
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• pp.108-112
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• 2002

We investigated the secondary electron emission characteristics of MgO layer used as the protecting material in a.c. plasma display panel(a.c.-PDPs) using a pulsed ion beam technique, where the surface charging can be effectively suppressed during the measurement. The measurement of the secondary electron emission coefficients ($\gamma$) on the surface of $SiO_2$ was carried out and then, it was found that the yields were dependent on incident ion energies. In addition, it was clearly demonstrated that the sputtering on MgO surface leads to lower yields, which suggests that the surface plays a key role on the operating conditions, such as life time, fast response, and etc.