• Journal of the Korean Ceramic Society
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• v.53 no.1
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• pp.13-17
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• 2016

It is highlighted that increasing the adsorbent surface area on volumetric basis is very important in providing an easy access for gas molecules. Fine particles around $3{\mu}m$ of soft-burned dolomite kiln dust (SB-DKD) were hydrated to wet slurry samples by ball mill process and then placed in a chamber to use spray dryer method. Spherical granules with particle size distribution of $50{\sim}60{\mu}m$ were prepared under the experimental condition with or without addition of a pore-forming agent. The relationship between bead size of the pore-forming agent and size of SB-DKD particles is the most significant factor in preparation of spherical granules with a high porosity. Whereas addition of smaller beads than SB-DKD resulted in almost no change in the surface porosity of spherical granules, addition of larger beads than SB-DKD contributed to obtaining of the particles with both 15 times larger average pore volume and 1 order of magnitude larger porosity. It is considered that spherical granules with improved $N_2$ gas adsorption ability may also be utilized for other atmospheric gas adsorption.

• Korean Journal of Metals and Materials
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• v.46 no.5
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• pp.304-309
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• 2008

Magnesium alloys containing $Mg_2Si$ particles, as a promising cheap heat-resistant magnesium alloy for automobile power train parts applications, are attracting more attention of both material scientists and design engineers. Modification of the Chinese script shape $Mg_2Si$ particle is a key for using this alloy in sand or permanent mould casting. In the present work, the modification effect of Sr and Sb on the corrosion properties of the Mg-5Al-2Si alloy was investigated. Sr or Sb addition promoted the formation of fine polygonal shape $Mg_2Si$ particles by providing the nucleation sites. Sr was more effective element than Sb for shape modification of Chinese script shape $Mg_2Si$. Such improved microstructure of the modified alloy resulted in large improvement in corrosion resistance as compared to unmodified Mg-5Al-2Si alloy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.10
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• pp.834-839
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• 2000

The structural properties that SEM photograph of ZnO varistors surface studied by fractal mathematics program were investigated to verify the relations of electrical characteristics. The SEM photograph of ZnO varistors surface were changed by binary code and the grain shape of that were analyzed by fractal dimension. The void of ZnO varistors surface was found by fractal program. The relation between grain density and electrical properties depend on fractal dimension. The grain size in ZnO varistors surface was decreased by increasing of Sb$_2$O$_3$ addition. The spinel structure was formed by Sb$_2$O$_3$addition and it was depressed the ZnO grain formation. The grain size of ZnO by Sb$_2$O$_3$addition were from 5 to 10[${\mu}{\textrm}{m}$]. Among of ZnO varistors, fractal dimension of ZnO4 was very high as a 1.764. The density of grain boundary in ZnO2 and ZnO3 varistors surface was 15[%] by formed spinal structure. The breakdown electric field of ZnO2 that fractal dimension has 1.752 was very high to be 8.5[kV/cm]. When the fractal dimensin was high, the grain shape of ZnO varistors was complex and the serial layers of ZnO grain was increased.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.3
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• pp.113-116
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• 2010

We report on the growth and characteristics of the structural and optical properties of InGaN nano-structures doped with antimony (Sb) as a catalyst. The use of catalyst has been explored to modify the growth and defect generation during strained layer heteroepitaxial growth. We performed the growth of the InGaN nano-structures on c-sapphire substrates using mixed-source hydride vapor phase epitaxy (HVPE). The characteristic of samples was measured by scanning electron microscope (SEM) and photoluminescence (PL). The aligning direction of c-axis of the InGaN nano-structures was changed from vertical to parallel or inclined to the surface of substrates when the Sb was added as a catalyst. The indium composition was estimated about 3.2% in both cases of with or without the addition of Sb in the InxGal-xN structures. From the results of InGaN nano-structures formed with the addition of Sb, we can expect the performance of optical devices would be more improved by reduced piezo-electric field if we use the InGaN nano-structures of which c-axes are aligned parallel to the substrates as an active layer.

• Korean Journal of Materials Research
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• v.21 no.4
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• pp.192-195
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• 2011

The electro-deposition of compound semiconductors has been attracting more attention because of its ability to rapidly deposit nanostructured materials and thin films with controlled morphology, dimensions, and crystallinity in a costeffective manner (1). In particular, low band-gap $A_2B_3$-type chalcogenides, such as $Sb_2Te_3$ and $Bi_2Te_3$, have been extensively studied because of their potential applications in thermoelectric power generator and cooler and phase change memory. Thermoelectric $Sb_xTe_y$ films were potentiostatically electrodeposited in aqueous nitric acid electrolyte solutions containing different ratios of $TeO_2$ to $Sb_2O_3$. The stoichiometric $Sb_xTe_y$ films were obtained at an applied voltage of -0.15V vs. SCE using a solution consisting of 2.4 mM $TeO_2$, 0.8 mM $Sb_2O_3$, 33 mM tartaric acid, and 1M $HNO_3$. The stoichiometric $Sb_xTe_y$ films had the rhombohedral structure with a preferred orientation along the [015] direction. The films featured hole concentration and mobility of $5.8{\times}10^{18}/cm^3$ and $54.8\;cm^2/V{\cdot}s$, respectively. More negative applied potential yielded more Sb content in the deposited $Sb_xTe_y$ films. In addition, the hole concentration and mobility decreased with more negative deposition potential and finally showed insulating property, possibly due to more defect formation. The Seebeck coefficient of as-deposited $Sb_2Te_3$ thin film deposited at -0.15V vs. SCE at room temperature was approximately 118 ${\mu}V/K$ at room temperature, which is similar to bulk counterparts.

• Journal of the Korean institute of surface engineering
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• v.29 no.4
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• pp.253-260
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• 1996

Regular spangle hot dip galvanized steel sheets were made in the zinc bath containing a small amount of Al and with the addition of Pb, Sb, Sb-Mg, Sb-Cu and Bi respectively whose average glosses were measured. Zero-spangle hot dip galvanized steel sheets were also made by spraying a 2% $NH_4H_2PO_4$ solution on molten coating surfaces with exactly the same chemical compositions as above used for regular spangle and whose glosses and corrosion losses were also evaluated. For manufacturing zero- spangle hot dip galvanized steel sheets with high brightness, the zinc bath with 0.02%Sb and the spraying of a 2% $NH_4H_2PO_4$ solution were proposed and for better brightness and corrosion resistance, the zinc bath with 0.02% Sb-0.50%Mg and the spraying of a 2% $NH_4H_2PO_4$ solution were also proposed.

• The Korean Journal of Ceramics
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• v.7 no.2
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• pp.58-62
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• 2001

The relationship between the addition of Sb$_2$O$_3$ and the color difference by solarization in photosensitive glasses was investigated. Glasses containing CeO$_2$ and Sb$_2$O$_3$ simultaneously and glasses with only CeO$_2$ were changed reddish and yellowish respectively after exposing to ultra violet ray. Color difference between compositions was represented by dominant wavelength and purity. Since, in glasses containing CeO$_2$ and Sb$_2$O$_3$ simultaneously, Sb$_2$O$_3$ as reduction agent affected Ce$^3+$ ions to increase in glass and more Ce$^4+$ ions were induced than in glasses with only CeO$_2$ during UV irradiation, more electrons released by photo-ionization, which were color centers, were trapped by Ce$^4+$. In conclusion, the introduction of Sb$_2$O$_3$ to photosensitive glasses with CeO$_2$ resulted in the change of color center concentration in glasses and prevented the solarization of photosensitive glasses with CeO$_2$.

• Advances in materials Research
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• v.7 no.1
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• pp.73-81
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• 2018

$TiO_2/CH_3NH_3Pb_{1-x}Sb_xI_{3-3x}Br_{3x}-based$ photovoltaic devices were fabricated by a spin-coating method using mixture solutions with $SbBr_3$. Effects of $SbBr3$, CsI or RbBr addition to $CH_3NH_3PbI_3$ precursor solutions on the photovoltaic properties where investigated. The short-circuit current densities and photoconversion efficiencies were improved by adding a small amount of $SbBr_3$, CsI or RbBr to the perovskite phase, which would be due to the doping effect of Sb, Br and Cs/Rb atom at the Pb, I and $CH_3NH3$ sites, respectively.

• Journal of Korea Foundry Society
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• v.11 no.6
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• pp.463-474
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• 1991

The effect of $0.01{\sim}0.10%$ Sb and Sn on the wear resistance of ductile cast iron was investigated. The hardness was increased with Sb to 0.10%, but the elongation and the impact value were decreased. The tensile strength was increased with up to 0.05% Sb, however decreased with $0.05{\sim}0.10%$ Sb. The hardness and the tensile strength were increased and the elongation was decreased with up to 0.10% Sn. The nodularity of graphite was decreased with above 0.08% Sb however Sn had no effect on that. When the maximum compressive stress was low ($42kg.f/mm^2$), the weigth loss was decreased with increased hardness and when that was high ($54kg.f/mm^2$ and $65kg.f/mm^2$), the weight loss did not depend upon the hardness. The pearlite stabilization with Sb and Sn increased with the wear resistance of ductile cast iron.

• Journal of Korea Foundry Society
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• v.25 no.1
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• pp.40-50
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• 2005

A series of heavy section ductile cast iron ingots with the cube length of 250mm were systematically investigated as functions of casting parameters of sand casting. Abnormal graphite formation was specially observed with the variation of Si content and Bi or Sb addition. Effects of chilling during casting and adaptation of riserless system were also examined, and proved to be effective for the prevention of both shrinkage and abnormal graphite such as chunky one. The formation of chunky graphite was effectively prevented by low Si content despite the promotion of pearlite matrix structure. The ferritic matrix was encouraged to form by high Si content and chunky graphite formation was effectively suppressed by the addition of Bi and Sb. Bi addition, however, was not good enough to control the microstructure owing to the sensitive cooling rate dependent inoculation behavior and relative low ability of nodulization. Sb addition, on the other hand, was proved to be effective for the microstructural control and enhancement of various mechanical properties such as strength, elongation, and impact energy. It may be suggested that optimized casting parameters should be applied to produce heavy section ductile cast iron with reliability.