• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.195.2-195.2
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• 2014

Nanodiamond (ND) is composed of inner diamond core and outer graphite shell. The size of ND used in this study was about 5 nm. The ND solution was dropped on silicon substrate and dried in air. Dried ND sample was purified by using annealing method in air. Then, 40 keV Fe ion was irradiated into the sample. The dose was varied from $1{\times}10^{14}$ to $1{\times}10^{16}ions/cm^2$. The post annealing was performed at 1073 K in the vacuum to recover diamond structure. The annealing at 873 K in air was performed to remove the outer graphite shell. The structure of ND was confirmed by X-ray diffraction (XRD) and Raman spectroscopy. We will present the detailed data and results in the conference.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.213-215
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• 2006

반응용액의 pH와 반응시간에 따른 용출실험 결과를 PHREEQC를 이용하여 용출된 중금속이 어떠한 화학적 형태가 우세한지 알아보고자 하였다. 용출용액에 용해된 Zn, Cd, Cu, Mn 및 Fe의 주요 존재형태는 free ion 및 sulfate complexes($metal-SO_4$)인 것으로 계산되었다. pH 5와 pH 3의 조건에서 각 원소의 화학적 존재형태는 서로 유사하고, 반응시간이 증가할수록 free ion 상태로 존재하는 비율은 감소하고 sulfate complexes로 존재하는 비율은 증가하는 경향을 보였다. pH 1에서 용출된 용액에 존재하는 각 원소의 화학적 존재형태는 sulfate의 농도가 크게 증가됨에도 불구하고 free ion 상태로 존재하는 금속이온의 함량의 증가비율보다 sulfate complexes로 존재하는 함량의 증가비율이 더 큰 것으로 예측되었다.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.304-304
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• 2012

CIGS(CuInGaSe2) 태양전지의 후면전극(Back contact)으로 널리 사용되는 Mo 박막은 낮은 면저항, 높은 반사율, 광흡수층 Na-path 제공 등의 조건이 요구된다. 일반적으로 Mo 박막 제작은 DC 마그네트론 스퍼터링 방법이 가장 널리 사용되며, 제작조건에 따라 태양전지 효율에 강한 영향을 미치는 것으로 보고되고 있다. 본 연구에서는 DC 마그네트론 스퍼터링 시 기판에 이온빔(Ion-beam)을 동시 조사하는 이온 빔 스퍼터링 증착(Ion-beam sputter deposition)법으로 Mo 박막을 제작하였다. 제작된 박막의 전기적 및 광학적 특성은 4-point probe, UV-Vis-NIR spectrometer로 각각 조사하였으며 Na-path 제어를 위한 구조적 특성은 XRD, FE-SEM으로 분석하였다. 분석결과에 따르면 기존 DC 마그네트론 스퍼터링 방법보다 상대적으로 더 치밀한 구조와 높은 반사율을 가지는 박막이 제작됨을 알 수 있었다. Mo 박막의 최적조건은 DC power 300 W, Ion-gun power 50 W, Ar flow rate 20 sccm 였다.

• Journal of Electrochemical Science and Technology
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• v.2 no.3
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• pp.136-142
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• 2011

$Li_4Ti_5O_{12}$ is prepared through a solid-state reaction between $Li_2CO_3$ and anatase $TiO_2$ for applications in lithium-ion batteries. The rate capability is measured and the electrode polarization is analyzed through the galvanostatic intermittent titration technique (GITT). The rate characteristics and electrode polarization are highly sensitive to the amount of carbon loading. Polarization of the $Li_4Ti_5O_{12}$ electrode continuously increases as the reaction proceeds in both the charge and discharge processes. This relation indicates that both electron conduction and lithium diffusion are significant factors in the polarization of the electrode. The transition metal (Cu, Ni, Fe) ion added during the synthesis of $Li_4Ti_5O_{12}$ for improving the electrical conductivity also greatly enhances the rate capability.

• Journal of Electrochemical Science and Technology
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• v.9 no.1
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• pp.51-59
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• 2018

Various Si-Fe-Al ternary alloys were prepared with the same amount of Si by the melt spinning technique. The feasibility of the capacity prediction approach based on the estimation of the active amount of Si using the phase diagram was practically examined and reported. These predictions were verified by the electrochemical test of fabricated coin cells and other characterization methods. The capacity prediction approach using the phase diagram might be a fundamental and efficient method to accelerate the practical application of Si-based alloys as the anode material for Li-ion batteries. The details on the prediction procedure were discussed.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.6
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• pp.609-609
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• 1998

This paper surveys the effect of rice straw ash solution to the physical properties of Sappan Wood dyeing fabrics. In the quantitative analysis of rice straw ash solution, the quantities of absorbed ingredients in fabrics were increased by bath pull treatment but the amount of absorption(K/S value) was increased by bath pH4.5 treatment. This is related to the metal ion. Among the metal ion, effect of Fe iou and Al ion were related. In case added extracted dye solution to mordants, the color dye solution became dark and increased reddish. The changes of mechanical properties of fabrics tensile resilience, bending rigidity(B), compressional resilience(RC) were increased. Generally mechanical properties were increased by rice straw ash solution treatment, specially bath pH9 treatment. Rice straw ash solution treatment of dyeing fabrics made the improvement in tensile strength and elongation and in the amount of absorption, dye ability, color fastness, mechanical properties, tensile strength, elongation.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.6
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• pp.699-705
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• 1998

This paper surveys the effect of rice straw ash solution to the physical properties of Sappan Wood dyeing fabrics. In the quantitative analysis of rice straw ash solution, the quantities of absorbed ingredients in fabrics were increased by bath pull treatment but the amount of absorption(K/S value) was increased by bath pH4.5 treatment. This is related to the metal ion. Among the metal ion, effect of Fe iou and Al ion were related. In case added extracted dye solution to mordants, the color dye solution became dark and increased reddish. The changes of mechanical properties of fabrics tensile resilience, bending rigidity(B), compressional resilience(RC) were increased. Generally mechanical properties were increased by rice straw ash solution treatment, specially bath pH9 treatment. Rice straw ash solution treatment of dyeing fabrics made the improvement in tensile strength and elongation and in the amount of absorption, dye ability, color fastness, mechanical properties, tensile strength, elongation.

• Journal of Electrochemical Science and Technology
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• v.10 no.1
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• pp.82-88
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• 2019

Here, we report on nanocrystalline Si-Al-M (M = Fe, Cu, Ni, Zr) alloys for use as an anode for lithium-ion batteries, which were fabricated via a melt-spinning method. Based on the XRD and TEM analyses, it was found that the Si-Al-M alloys consist of nanocrystalline Si grains surrounded by an amorphous matrix phase. Among the Si-Al-M alloys with different metal composition, Ni-incorporated Si-Al-M alloy electrode retained the high discharge capacity of 2492 mAh/g and exhibited improved cyclability. The superior $Li^+$ storage performance of Si-Al-M alloy with Ni component is mainly responsible for the incorporated Ni, which induces the formation of ductile and conductive inactive matrix with crystalline Al phase, in addition to the grain size reduction of active Si phase.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.2
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• pp.71-97
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• 1974

Many studies on the changes of the materials in the water-logged paddy soil have been reported, but there will be several problems to apply them on the field soil. The main differences between the method of soil packed in beaker or column tube to that of natural field furrow slice are with or without of the rice root and the effect of water percolation. On the other hand, the mechanism of the water percolation on the changes of material in the natural field furrow slice are gradually understood. The purpose of this experiment is to know the effect of the rice cultivation on the chemical and physical changes of material in the water-logged paddy soil. Obtained results are as follows. 1. The physical and chemical changes on the water-logged paddy soil in the non-planted control-plot were nearly the same as the beaker or column tube experiment, while in the planted plot, slightly altered patterns were observed. 2. The relation between the number of tillers and total cation, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$, Fe and Mn in the leachate showed very high significance. T hisresult showed that the leaching of those cation was promoted by growing of the rice r- of the rice root. 3. On the other hand, the concentration of the potassium, silica and phosphorus in leachates was gradually decreased and that of $NH_4$-N could not detect after the stage of active tillering. These facts revealed that such components were absorbed by rice plant. 4. The highly significant correlation between the number of tillers and the concentration of the total cation, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$, $Fe^{{+}{+}}$, Fe and Mn in the percolated water was observed except that of $Mg^{{+}{+}}$. It was also showed that the rice root promoted the leaching of those cation. 5. The very high significance in the correlation between $HCO_3{^-}$ and the number of tillers indicated that the higher activity of the rice root was, the more $HCO_3{^-}$ concentration in the leachate was increased. 6. The relationship between the $HCO_3{^-}$ and the total cation, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$, $Fe^{{+}{+}}$, Fe and Mn was appeared very highly significant. $HCO_3{^-}$, the metabolite of the rice root, promoted the leaching of $Ca^{{+}{+}}$, $Mg^{{+}{+}}$, $Fe^{{+}{+}}$ and Mn. This fact might be a result that these cations were leached as the form of bicarbonate. 7. The iron in the leachate was the form of $Fe^{{+}{+}}$ and the correlation between $Fe^{{+}{+}}$ and $HCO_3{^-}$ was very highly significant. This result indicated that it seemed to be ferrous bicarbonate when it is leached out. 8. In the rhizosphere, ferrous iron was decreased gradually and the concentration of glucose was as high as 2 to 3 times in comparison with the other parts of the soil. These facts were the same as the previous reports in which rhizosphere was oxidized by the oxigen excreted from the root, and was enriched by the organic matter which was also excreted from the root and accumulated residues of the root. 9. ${\beta}$-Glucosidase and phosphatase activity in the rhizosphere was higher than that of the other parts of the soil. This facts might be attributed to the vigorous activity of microorganism in the rhizosphere where glucose concentration was high. 10. The pH in the leachate of the planted plot was lower than that of control, and the Eh on the planted soil was elevated in the last stage.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.4
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• pp.312-317
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• 2004

High dose ($3{\times}10^{16}cm^{-2}$) implantation of Fe or Ni ions into bulk, single-crystal ZnO substrates was carried out at substrate temperature of ${\sim}350^{\circ}C$ to avoid amorphization of the implanted region. The samples were subsequently annealed at $700^{\circ}C$ to repair some of the residual implant damage. X-Ray Diffraction did not show any evidence of secondary phase formation in the ZnO. The Ni implanted samples remained paramagnetic but the Fe-implanted ZnO showed evidence of ferromagnetism with an approximate Curie temperature of ${\sim}$240K. Preliminary X-Ray Photoelectron Spectroscopy measurements showed the Fe to be ill the 2+ oxidation state. The earrler density in the implanted region still appears to be too low to support carrier-meditated origin of the ferromagnetism and formation of bound magnetic polarons may be one potential explanation for the observed magnetic properties, No evidence of the Anomalous Hall Effect could be found in the Fe-implanted ZnO, but its transport properties were dominated by the conventional or ordinary Hall effect.