• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2004년도 춘계총회 및 연구발표회 초록집
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• pp.51.2-51.2
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• 2004

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.127.1-127
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• 2003

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 춘계학술연구발표회(한국결정학회)
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• pp.18-18
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• 2002

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1996년도 The 9th KACG Technical Annual Meeting and the 3rd Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.527-527
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• 1996

• 한국세라믹학회지
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• 제42권9호
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• pp.602-606
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• 2005

[ $LiCoO_{2}$ ] is the most common cathode electrode materials in Lithium-ion batteries. $LiCo_{0.97}Mg_{0.03}O_2$ was synthesized by the solid-state reaction method. We investigated crystal structures, electrical conductivities and electrochemical properties. The crystal structure of $LiCo_{0.97}Mg_{0.03}O_2$ was analyzed by X-ray powder diffraction and Rietveld refinement. The material showed a single phase of a layered structure with the space group R-3m. The lattice parameter(a, c) of $LiCo_{0.97}Mg_{0.03}O_2$ was larger than that of $LiCoO_2$. The electrical conductivity of sintered samples was measured by the Van der Pauw method. The electrical conductivities of $LiCoO_2$ and $LiCo_{0.97}Mg_{0.03}O_2$ were $2.11{\times}10^{-4}\;S/cm$ and $2.41{\times}10^{-1}\;S/cm$ at room temperature, respectively. On the basis of the Hall effect analysis, the increase in electrical conductivities of $LiCo_{0.97}Mg_{0.03}O_2$ is believed due to the increased carrier concentrations, while the carrier mobility was almost invariant. The electrochemical performance was investigated by coin cell test. $LiCo_{0.97}Mg_{0.03}O_2$ showed improved cycling performance as compared with $LiCoO_2$.

• 한국결정성장학회지
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• 제16권5호
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• pp.222-226
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• 2006

Carboxylated styrene-butadiene계 액상 첨가제가 칼라 보도 블록 무기 안료층의 미세구조, 기계적 특성 및 탈색 저항성에 미치는 영향에 대하여 조사하였다. 액상 첨가제를 첨가함에 따라 겉보기 기공률과 흡수율이 감소한 더 치밀한 미세구조와 균일한 안료 분포를 나타내는 무기 안료층을 얻을 수 있었다. 또한 기계적 강도 및 탈색저항성이 현저히 향상됨을 확인하였다.

• Journal of Pharmaceutical Investigation
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• 제41권1호
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• pp.45-50
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• 2011

Nonclassical pathway of crystallization has been utilized to modify the properties and morphologies of inorganic and organic/inorganic materials. In here, the polymer-directed crystallization method has been applied to the pharmaceutical active ingredient to assess the applicability for as a particle engineering tool. The polymer-directed crystallization was successful to modifying the crystal size, habit and morphology, but it was not effective to discover the novel polymorphs of Sibutramine (SB). SB was selected as a model drug and polyacrylic acid (PAA), polyethylene imine (PEI) and chitosan (CHI) were added as a crystallization pathway modifier. SB was crystallized via drowning crystallization using methanol or ethanol as a solvent and water as a non-solvent. The significant interactions between polymer and the drug were confirmed by measuring the solubility of the drug in presence of polymer during the crystallization. The crystal forms of SB are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and optical microscope (OM). The polymer-directed crystallization seems to be able to modify the crystal properties of pharmaceutical active ingredient, which is critical in determining the bioavailability, processability, and stability.

• 한국결정성장학회지
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• 제5권3호
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• pp.215-222
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• 1995

Floating zone법으로 $SrTiO_3$에 $Nb_2O_5$를 02wt% 첨가한 단결정을 육성하였다. 결정성장시 성장분위기로는 air와 질소분위기에서 각각 결정을 육성하였으며, 원료봉의 소결온도 따른 성장계면양상을 조사하였다. 성장조건으로는 성장속도는 5mm/hr, 상부축과 하부축의 회전속도는 30rpm이었고, air분위기시 air의 유량은 1.5 ${\ell}/min$, 질소분위기시 질소가스의 유량은 0.5 ${\ell}/min$이었다. 육성한 결정을 XRD, Laue, chemical etching 등의 분석을 하였으며, 질소분위기에서 annealing 한 후 비저항을 측정하였으며 이를 통해 activation energy를 조사하였다.

• 한국결정성장학회지
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• 제9권6호
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• pp.547-552
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• 1999

Langasite$(La_{3}Ga_{5}SiO_{14})$ single crystal was successfully grown by Floating Zone (FZ) method and characterized. The growth rate was 1.5 mm/h and the rotation speed was 15 rpm for an upper rotation and 13 rpm for a lower rotation. The grown crystal was 12 mm in length and 6 mm in diameter. The grown crystal was dark orange color and it was grown along [001] direction. The composition of grown crystal and the structure were analyzed using XRD and WDS. The electrical properties of grown crystal at various frequencies and temperatures were discussed.

• The Korean Journal of Ceramics
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• 제2권4호
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• pp.184-187
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• 1996

Diamod nucleation by mw assisted CVD was examined various conditions namely, (1) diamond nucleation on variour substrate materials, such as Si, cubic BN, pyrolytic BN and AIN, (2) AST(Activated species transport) method which promote nucleation of diamond on single crystal and polycrystalline alumina substrate was developed. (3) Effect of bias enhancement of nucleation on single crystalline Si was examined, and finally (4) DST (Double step treatment) method was developed to enhance diamond nucleation on Ni. In this method, we separated carbon diffusing process into Ni, carbon precipitating process from the inside of Ni and diamond precipitation process.