• Proceedings of the Korean Magnestics Society Conference
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• 2009.12a
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• pp.71-71
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• 2009

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2004.11a
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• pp.114-114
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• 2004

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.32-32
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• 2009

실리콘 박막 태양전지에서 전면 투명전도막(TCO)은 태양전지의 전기, 광학적 특성을 결정하는 중요한 기능을 한다. ZnO:Al TCO는 기존에 사용되던 $SnO_2:F$와는 비정질 실리콘(a-Si:H) 박막 태양전지의 윈도우 층으로 사용되는 p a-SiC:H와의 일함수(work function) 차이로 인해 접촉전위(contact barrier)를 형성하게 되며 이로 인해 태양전지의 충진율(fill factor)이 $SnO_2:F$에 비해 감소하는 단점을 보인다. 본 연구에서는 ZnO:Al/p a-SiC:H 계면의 접촉전위 발생원인 및 태양전지 충진율 감소현상에 관한 정확한 원인규명을 위해 다양한 특성을 갖는 버퍼층을 삽입하여 계면특성 및 태양전지의 동작특성을 분석하고자 한다.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.323-329
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• 2020

The cathodic hydrogen evolution ability of different pure metals and their long term galvanic corrosion behavior with pure Mg were investigated. The hydrogen evolution ability of pure Ti, Al, Sn and Zr is weak, while that of Fe, W, Cr, and Co is very strong. Initial polarization test could not completely reveal the cathodic behavior of the tested metals during long term corrosion. The cathodic hydrogen evolution ability may vary significantly in the long term galvanic tests for different metals, especially for Al whose cathodic current density reduced to 1/50 of the initial value. The anodic polarization shows that Al and Sn as alloying elements are supposed to provide relatively good passive effect for Mg alloy, while Ag can provide a slight passive effect and Zn has little passive effect.

• Journal of Information Display
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• v.10 no.4
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• pp.137-142
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• 2009

Transparent top-gate Al-Zn-Sn-O (AZTO) thin-film transistors (TFTs) with an $Al_2O_3$ protective layer (PL) on an active layer were studied, and a transparent 2.5-inch QCIF+AMOLED (active-matrix organic light-emitting diode) display panel was fabricated using an AZTO TFT backplane. The AZTO active layers were deposited via RF magnetron sputtering at room temperature, and the PL was deposited via two different atomic-layer deposition (ALD) processes. The mobility and subthreshold slope were superior in the TFTs annealed in vacuum and with oxygen plasma PLs compared to the TFTs annealed in $O_2$ and with water vapor PLs, but the bias stability of the TFTs annealed in $O_2$ and with water vapor PLs was excellent.

• Journal of the Korean Ceramic Society
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• v.36 no.12
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• pp.1322-1326
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• 1999

In2O3 thick film gas sensor for detecting NOx gas of high concentration was fabricated by a screen printing technique. This work focussed on investigation of the change of sensitivity to NOx gas with firing temperatures of sensing layer and on improvement of the sensitivity by adding catalysts such as Al,. Ru, and SnO2 The cross sensitivites of sensor to CO, H2, CH4 and i-C4H10 gases were also examined under NO2 gas concentration of 200ppm Pure In2O3 gas sensor prepared at a firing temperature of 50$0^{\circ}C$ showed a maximum sensitivity to NOx gas at the operating temperature of 40$0^{\circ}C$ Al(0.004 wt%)-In2O3 sensor largely improved the sensitivities to both NO2 and NO gas and showed a superior selectivity compared with other gas sensors.

• YAKHAK HOEJI
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• v.45 no.5
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• pp.460-467
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• 2001

Heavy metals, such as Al, As, Cd, Cr Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, Si, Sn, V and Zn, were analysed on kidney cortex and medulla of Korean obtained from 154 forensic medical autopsy cadavers. Heavy metals were analysed by inductively coupled plasma atomic emission spectrometry In kidney cortex, the concentrations of Al, Cd, Cu, Mn, Mo, Pb, Se, Si and Zn were significantly higher than in the kidney medulla (Cd, Cu, Mn, Mo, Zn : p<0.01, AA, Pb, Se, Si : p<0.05). No significant local differences were found between kidney cortex and kidney medulla in the concentrations of As, Cr Fe, Hg, Ni, Sn and V. In kidney cortex and kidney medulla, Cd concentrations correlated positively with age, but Mn concentrations correlated negatively with age. A significantly positive correlation between Cd and Zn, Cd and Cu, Zn and Cu, Al and Si, Se and As was found in kidney cortex and kidney medulla. A significantly positive correlation between Hg and Se was only observed in kidney cortex. These results indicate that the distribution of hazardous heavy metals is similar to that of essential elements in the tissues.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.05a
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• pp.214-223
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• 2005

In order to recover valuable metals from fine-grained electronic waste, bioleaching of Cu, Zn, Al, Co, Ni, Sn and Pb were carried out using Aspergillus niger as a leaching microorganism in a shaking flask. Aspergillus niger was able to grow in tile presence of electronic scrap. The formation of organic acids(citric and oxalic acid) from Aspergillus niger caused the mobilization of metals from waste electronic scrap. In a preliminary study, in order to obtain the data on the leaching of Cu, Zn, Al, Co and Ni, the metal leaching behaviours were accomplished using Organic acid(Citric acid and Oxalic acid) instead of Aspergillus niger. At the electronic scrap concentration of 50g/L, Aspergillus niger were able to leach more than 95% of the available Cu, Co. But Al, Zn, Pband Sn were able to leach about 15-35%. Ni and Fe were detected in the leachate less than 10%.

• Journal of Sensor Science and Technology
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• v.15 no.3
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• pp.211-215
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• 2006

Conducting polymer (Polypyrrole) and Tin oxide ($SnO_{2}$) composite films have been fabricated with layer-by-layer technique. $SnO_{2}$ layer was screen-printed on $Al_{2}O_{3}$ substrate and then was dip-coated with polypyrrole (Ppy). The microstructures of composite films were evaluated by a field emission scanning electron microscope (FE-SEM) and FTIR spectral analysis. The change in sensitivity to various VOCs was observed. The target VOCs were methanol, ethanol, benzene and toluene. The sensitivities of the $Ppy/SnO_{2}$ sensor to benzene and toluene were very low at 1000 ppm (2.1 %, 1.5 %), while the sensitivities to methanol and ethanol was high (9 %, 11 %). It indicates that the sensors have selectivity to alcoholic gases such as methanol and ethanol.

• Journal of the Korean Chemical Society
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• v.29 no.2
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• pp.129-136
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• 1985

In the atomic absorption spectrometry using an air-acetylene flame, the interferences of Zr, Sn, Al, Sb, $SO_4^{2-},\;VO_3^-,\;and\;SiO_3^{2-}$, on the calcium absorption and the repression of this interference by the addition of cerium have been studied. The interference by Zr, Sn, Al, Sb, $SO_4^{2-},\;VO_3^-,\;and\;SiO_3^{2-}$ existed as the same concentration as calciurn ($3.0 {\times} 10^{-4}$M) in the sample solution are completely released by the addition of cerium twice as much as interfering cation. The interferences by the mixed interfering cations (Zr, Sn, Al and Sb) and by the mixed interfering anions ($SO_4^{2-},\;VO_3^-,\;and\;SiO_3^{2-}$) are larger than by each interfering cation and anion, and the releasing effect by cerium ($1.5 {\times} 10^{-2}$M) is effective up to some degree of the concentration of mixed interfering cations and of mixed interfering anions. The releasing effect by cerium to the mixed solution of interfering cations and anions is applicable to quite wide range of concentration.