• Journal of the Korean Chemical Society
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• v.13 no.1
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• pp.13-15
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• 1969

This investigation is to make comparative evaluation of the corrosion inhibiting effects of quinoline, oxine and 7-nitroso 8-hydroxy quinoline (7NHQ). In case of quinoline, and oxine, since the N atom in them functions as cation, the process involved is assumed to be cathode control. On the other hand 7-NHQ was found to form a stable chelate compound with $Fe^{++}$ ion in acidic solution and shows as anode control predominantly. After plotting polarization curves, Tafel parameters were calculated in each solution involving the inhibitors, at the same time corrosion inhibiting effects were separately measured and compared from data of both corrosion current and analytical method.

• Proceedings of the Korean Magnestics Society Conference
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• 2005.12a
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• pp.36-37
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• 2005

• Proceedings of the Korean Vacuum Society Conference
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• 2005.08a
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• pp.42-43
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• 2005

• Carbon letters
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• v.18
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• pp.80-83
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• 2016

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.11a
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• pp.46-46
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• 2007

Zn, Al 및 Sn을 각각 도금한 강기판상에 Mg박막을 이온플레이팅법에 의해 제작하였다. 이와 같은 중간층을 가진 Mg막의 내식측정결과에 의하면, Mg과 갈바닉 전위차가 작은 Zn을 중간층으로 하여 제작한 Mg 막이 Fe 모재보다 낮은 자연 전위값을 안정적으로 유지하면서 희생양극적 방식효과를 장시간동안 나타내었다.

• Korean Journal of Remote Sensing
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• v.8 no.1
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• pp.1-13
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• 1992

The study is to analize the spectral characteristics of metamorphic rocks by their spectral reflectance curves obtained from CARY 17-D Spectrophotometer. Coarse grained rocks generally show strong absorption at 1.4 and 1.9 $\mu\textrm{m}$ due to preserved water inclusion in quartz of feldspar. The basic rocks show a broad absorption due to Fe$^{++}$ ion rich in mafic minerals. Strong absorption near 2.0$^+\mu\textrm{m}$ suggests existence of carbonate or clay minerals.

• Bulletin of the Korean Chemical Society
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• v.15 no.6
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• pp.424-427
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• 1994

Effects of iron compounds in known biomimetic oxidation systems (Gif IV and GoAgg II) have been studied on activity and ketone/alcohol selectivity of cyclohexane oxidation. Both ketone/alcohol ratio and cyclohexane conversion were affected by counter-ion Z of iron compounds Z-Fe. When Z has a more electron withdrawing property, the reactivity is increased and the formation of ketone is favored. From these experimental results, a new mechanism is proposed for the biomimetic oxidation system.

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.288.1-288.1
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• 2008

• Journal of the Mineralogical Society of Korea
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• v.29 no.2
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• pp.47-58
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• 2016

The Fe-component of pyrophyllite is an impurity that reduces its grade in the final product. In order to identify the amount of impurity in pyrophyllite and to remove the Fe from the ore using a dry method, microwave heating and magnetic separation were carried out. Pyrite and hematite were identified to contain pyrophyllite by microscopy, XRD, XRF, SEM/EDS and EPMA analysis. It is suggested that the euhedral pyrite in the pyrophyllite is formed by hydrothermal solution, and then the dissolution cavity structure is formed with a partial remainder of the pyrite which dissolved in acidic water. And the $Fe^{3+}$ ion contained in the acidic water precipitated out in the concentric structure of hematite as the origin of sedimentary structure. As a result of the microwave heating and magnetic separation experiments, the Fe removal rates obtained were 96% and 93% from pyrophyllite ore from the Sunsan mine and Wando mine, respectively. It is confirmed that the microwave heating and magnetic separation method was an environmentally friendly method to upgrade the low-grade pyrophyllite.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4205-4209
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• 2011

The $Li_2Mn_{0.5}Fe_{0.5}SiO_4$ silicate was prepared by blending of $Li_2MnSiO_4$ and $Li_2FeSiO_4$ precursors with same molar ratio. The one of the silicates of $Li_2FeSiO_4$ is known as high capacitive up to ~330 mAh/g due to 2 mole electron exchange, and the other of $Li_2FeSiO_4$ has identical structure with $Li_2MnSiO_4$ and shows stable cycle with less capacity of ~170 mAh/g. The major drawback of silicate family is low electronic conductivity (3 orders of magnitude lower than $LiFePO_4$). To overcome this disadvantage, carbon composite of the silicate compound was prepared by sucrose mixing with silicate precursors and heat-treated in reducing atmosphere. The crystal structure and physical morphology of $Li_2Mn_{0.5}Fe_{0.5}SiO_4$ was investigated by X-ray diffraction, scanning electron microscopy, and high resolution transmission electron microscopy. The $Li_2Mn_{0.5}Fe_{0.5}SiO_4$/C nanocomposite has a maximum discharge capacity of 200 mAh/g, and 63% of its discharge capacity is retained after the tenth cycles. We have realized that more than 1 mole of electrons are exchanged in $Li_2Mn_{0.5}Fe_{0.5}SiO_4$. We have observed that $Li_2Mn_{0.5}Fe_{0.5}SiO_4$ is unstable structure upon first delithiation with structural collapse. High temperature cell performance result shows high capacity of discharge capacity (244 mAh/g) but it had poor capacity retention (50%) due to the accelerated structural degradation and related reaction.