• 전기의세계
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• v.29 no.6
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• pp.344-348
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• 1980

$SF_{6}$가스의 절연파괴특성 및 화학적특성에 관한 것을 종합해보면, 첫째, $SF_{6}$의 방전은 1개의 전자 avalanche중의 전자수가 임계치 Norit가 $10^{8}$정도에서 streamer에의 전이가 일어나므로서 이루어지며, 둘째, $SF_{6}$의 (.alpha.-.eta.)/.rho.와 E/.rho.의 관계는 .alpha.=.eta.근방에서 직선으로 상승되어 절연파괴에 극히 중요한 뜻을 가지며, 셋째, 두번째의 .alpha.=.eta.에 있어서의 구배는 보통의 기체보다 수 10배크기 때문에 최대전계를 부여하는 전극근방만이 공극의 방전개시를 지배하며, 넷째, 전기기구에 있어서 $SF_{6}$가스의 화학적변화의 energy원으로서는 arc, corona, 열을 들 수 있으며 특히 $SF_{6}$가스중과 공기중과의 내 Corona성을 구하기 위한 인가전압일내 Corona수명시간은 $SF_{6}$가스중이 공기중보다 길다는 것이다.

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.195-202
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• 1988

An electrochemical reduction on the 3-phenyl-4-nitrosydnone in acetonitrile solution has been studied by direct current, differential pulse polarography, cyclic voltammetry and controlled potential coulometry. Before the cleavage of phenyl-N single bond a irreversible electron transfer-chemical reaction(EC) mechanism of nitro functional group proceeded to form amino (or-hydroxylamino) group by multielectron transfer which is followed to give phenyl hydrazine by single electron transfer-chemical reaction at the 2nd and 3rd irreversible reduction wave of high negative potential region. The cathodic half-wave potentials shown to be shift negative due to inhibitory effect of cetyl-trimethyl ammonium bromide micelle while reversible anodic peaks on the 2nd and 3rd reduction waves in the presence of NaLS at high negative potential region.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.1065-1069
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• 1998

This study was investigated to improve peformance of carbon negative electrode for lithium ion secondary battery. The carbon electrode was prepared by mixing with graphitic carbon material, natural graphite, and nongraphitic carbon material, petroleum cokes, which was heat-treated at $700^{\circ}C$ for l hour. Its electrochemical and charge-discharge characteristics were tested according to mixing ratio of different two types of carbon material. The carbon electrode prepared with various mixing ratio showed both charateristcs of two different types of carbon materials and the best characteristics as carbon electrode was demonstrated at mixing ratio of 1:1.

• Journal of the Korean Electrochemical Society
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• v.5 no.2
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• pp.62-67
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• 2002

The corrosion of the metallic cell components is blown to be one of the major reason f3r the performance degradation and subsequently the life-time limitation of the MCFC. To elucidate the corrosion phenomena, a corrosion study with the AISI-type 316L stainless steel, the most widely used separator material, in 621Li/38K carbonate eutectic melt was carried out. Corrosion phenomena in an MCFC were observed to differ from one location to another due to different environmental condition. The stability of passive film was found to be responsible fur the variations in corrosion phenomena. According to the potentiodynamic analysis, the passive film formed in anode-gas environment was less stable than in cathode-gas environment. The potentiostatic method combined with XRD analysis in addition to the cyclicvoltammetry was conducted to get an insight on variety corrosion reaction of AISI-type 316L stainless steel in a carbonate melt.

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.186-194
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• 1988

The electrochemical reduction of O,O-dimethyl-O-(3-methyl-4-nitrophenyl)-phosphorothioate (Fenitrothion) has been studied in acetonitrile solution containing surfactant micelle by direct current (DC)-differential pulse (DP) polarography, cyclic voltammetry (CV) and controlled potential coulometry (CPC). The partially reversible electron transfer-chemical reaction(EC, EC mechanism) of fenitrothion reduction proceeded by four electron transfer to form O,O-dimethyl-O-(3-methyl-4-hydroxyaminophenyl)-phosphorothioate which undergoes single bond of the phosphorus atom and phenoxy group cleaves to give p-amino-m-cresol and dimethyl thiophosphinic acid as major product by two electron transfer-protonation at higher negative potential. The polarograpic reduction waves shown to suppressed due to inhibitory effect of sodium lauryl sulfate micelle solution and split up on selectivity of anionic micelle effect in two step at the first reduction peak.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.2
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• pp.55-61
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• 1989

This is a basic experimental research tried to use electric furnace slag as a fine aggregate for concrete. Chemical component and physical properties of electric furnace slag were studied, and expansion mechanism and aging method for stabalization of electric furnace slag were discussed. Concrete properties electric furnace slag as a fine aggregate were also studied in this paper.

• Journal of the Korean Electrochemical Society
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• v.4 no.4
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• pp.176-181
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• 2001

This article covers the fundamentals of underpotential deposition (UPD), focussing on the importance of UPD in interfacial electrochemistry. Firstly, this article described the basic concepts of UPD, including underpotential shift and electrosorption valency. Secondly, the present article explained UPD of hydrogen, followed by hydrogen evolution or hydrogen absorption, giving special attention to the adsorption sites of hydrogen on metal surface and the absorption mechanism into Pd. Finally, this article briefly presented the important factors associated with UPD in various fields of interfacial electrochemistry from practical viewpoints.

• Journal of the Korean Institute of Gas
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• v.9 no.1 s.26
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• pp.21-25
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• 2005

This paper was studied on the corrosion behavior of STS 304 for gas boiler in the condensed water, the electrochemical polarization test of STS 304 for gas boiler in the condensed water was carried out. And the corrosion behavior of STS 304 was considered. The main results are as following: 1) As corrosion environment is acidified from neutrality, the polarization resistance of STS 304 decreases and the corrosion potential is less noble. 2) The corrosion reaction mechanism of STS 304 is cathodic control. 3) As corrosion environment is acidified, the passive potential range of STS 304 decreases. Also, the passive current density of STS 304 increases.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.103.1-103.1
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• 2011

고체 산화물 연료전지(SOFC)는 크게 음극(anode), 양극(cathode), 전해질(electrolyte)로 구성되 있으며 연결자를 통해 직렬 또는 병렬로 연결된 형태로 발전장치 등에 활용되고 있다. 이중 연료의 산화반응을 담당하고 있는 연료전지의 음극으로 지금까지 Cobalt, Platinum, Palladium 등의 전이금속 또는 귀금속들이 사용되었지만 현재는 Nickel 또는 Nickel을 함유한 물질들 특히, Ni-YSZ 복합체가 주로 사용되고 있다. Ni-YSZ 복합체는 가격과 성능 등 여러가지 면에서 SOFC의 음극으로 사용하기에 가장 적합한 물질인데 특히 전지의 지지체 역할과 동시에 전극으로서의 역할도 병행해야하는 음극 지지형 SOFC의 경우 Ni-YSZ 복합체의 효용성을 더욱 커지게 된다. 본 연구에서는 SOFC의 음극물질로 가장 널리 쓰이고 있는 Ni-YSZ 복합체를 core shell 형태로 만들어 전도 path를 효율적으로 하고 그 특성을 최적화하기 위한 미세구조 및 소결 거동, 전기적 특성을 평가하였다.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.246-251
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• 2003

전기분해법을 이용하여 수용액 중의 질산성 질소의 환원거동에 대한 연구를 통하여 수용액중의 질산 함량을 제어하는 연구를 수행하였다. 촉매전극을 채택한 복극전해조에서 30분의 조업에 질산 100ppm 이하의 저농도 용액은 70%, 300ppm 이상의 고농도의 경우는 90%까지 질소를 용이하게 제거할 수 있었다. 초기 질소농도가 증가하면서 한계전류밀도도 크게 증가하였으며, pH가 감소할수록 환원전류가 증가하였다. 그리고 수용액의 pH는 질소 환원반응기구에 큰 영향을 주는 것으로 판명되었으며, 산성에서는 질소형태로 중성 혹은 염기성에서는 암모니아 형태로 환원되는 것으로 추정된다.