• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of the Pharmaceutical Society of Korea
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• pp.77-77
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• 2001

• 대한기계학회논문집B
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• 제20권10호
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• pp.3322-3333
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• 1996

A numerical analysis has been conducted to investigate a modified floating-zone crystal growth process in which most of the melt surface is covered with a heated ring. The crystal rod is not only pulled downward but rotated around its axisymmetric line during crystal growth process in order to produce the flat interface of crystal growth and the single crystal growth of NaNO3 is considered in 6mm diameter. The present study is made from a full-equation-based analysis considering a pulling velocity in all of solid and liquid domains and both of solid-liquid interfaces are tracked simultaneously with a governing equation in each domain. Numerical results are mainly presented for the comparison of the surface shape of rotational crystal rod with that of no-rotational crystal rod and the effects of revolution speeds of the crystal rod. Results show that the rotation of crystal rod produces more its flat surface. In addition, the shape of crystal growth near the centerline is more concaved with the increase in the revolution speed of crystal rod. The flow pattern and temperature distribution is analyzed and presented in each case. As the pulling velocity of crystal rod is increasing, the free surface of the melt below the heated ring is enlarged due to the crystal interface migrating downward.

• 한국미생물·생명공학회지
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• 제26권3호
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• pp.269-274
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• 1998

Triphenylmethane계 염료 탈색균인 E. cloacae MG 82를 이용한 crystal violet의 탈색 특성을 조사하였다. 배지내의 용존산소의 양이 많을수록 crystal violet의 탈색과 E. cloacae MG82의 균생장이 좋았다. 균생장 중기의 세포 군에서 crystal violet의 탈색능이 가장 활발하였고 염료의 농도가 높아짐에 따라 균생장과 탈색능이 억제되었으며, 균생장이 가능한 crystal violet의 최고 농도치는 375 $\mu$M이었다. E. cloacae MG82는 crystal violet을 유일한 탄소원으로 이용할 수 없었고, 균생장 및 염료의 탈색에 또 다른 에너지원을 필요로 하였다.

• 한국결정성장학회지
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• 제19권5호
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• pp.215-222
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• 2009

Many concepts of external magnetic field applications in crystal growth processes have been developed to control melt convection, impurity content and growing interface shape. Especially, travelling magnetic fields (TMF) are of certain advantages. However, strong shielding effects appear when the TMF coils are placed outside the growth vessel. To achieve a solution of industrial relevance within the framework of the $KRISTMAG^{(R)}$ project inner heater-magnet modules(HMM) for simultaneous generation of temperature and magnetic field have been developed. At the same time, as the temperature is controlled as usual, e.g. by DC, the characteristics of the magnetic field can be adjusted via frequency, phase shift of the alternating current (AC) and by changing the amplitude via the AC/DC ratio. Global modelling and dummy measurements were used to optimize and validate the HMM configuration and process parameters. GaAs and Ge single crystals with improved parameters were grown in HMM-equipped industrial liquid encapsulated Czochralski (LEC) puller and commercial vertical gradient freeze (VGF) furnace, respectively. The vapour pressure controlled Czochralski (VCz) variant without boric oxide encapsulation was used to study the movement of floating particles by the TMF-driven vortices.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.159-162
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• 2009

A liquid crystalline monomer is applicable to fabricate a retarder in which various types of alignment are fixed. We have developed the monomer, UV-curable liquid crystal optimized for coating processes. Applications and materials for the retarder are reviewed.

• 한국결정성장학회지
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• 제33권4호
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• pp.158-164
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• 2023

다이아몬드 결정구조가 갖는 의미와 결정형태의 조형적 아름다움을 새로운 관점에서 디자인하여 주얼리로 표현하고자 하였다. 본 연구에서는 다이아몬드의 결정구조에 대한 문헌 조사와 다이아몬드 결정구조의 조형적 특징을 모티브로 한 주얼리 디자인 사례를 분석하였다. 다이아몬드 결정구조의 의미와 가치를 새롭게 해석하고, 다이아몬드의 결정구조를 주얼리로 디자인함으로써 결정구조가 갖는 미적 효과를 나타낼 수 있는 조형적 디자인을 연구하였다. 다이아몬드 결정구조가 주는 대칭의 효과와 조형미가 주는 반복의 특징을 살려 주얼리 디자인을 제시함으로써 보석이 주는 근원적인 아름다움, 문화적 의미가 새롭게 재인식되길 기대해 본다.

• 한국결정성장학회지
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• 제28권4호
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• pp.148-151
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• 2018

물리기상이동법(Physical Vapor Transport(PVT) method)을 적용하여 질화알루미늄 단결정을 성장하였다. 자체적으로 성장하고 제조한 직경 33 mm 크기의 종자결정을 사용하여 직경 46 mm, 길이 7.6 mm 크기의 벌크단결정을 성장하였으며, 성장 온도는 $1950{\sim}2100^{\circ}C$, 성장 압력은 0.1~1 atm의 범위에서 조절하여 반복 성장을 통하여 성장한 결과를 보고하고자 한다.

• 한국전산유체공학회지
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• 제3권1호
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• pp.100-107
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• 1998

A numerical analysis of thermal stress over temperature variations near the crystal-melt interface is carried out for a floating-zone growth of Cadmium Telluride (CdTe). Thermocapillary convection determines crystal-melt interfacial shape and signature of temperature in the crystal. Large temperature gradients near the crystal-melt interface yield excessive thermal stresses in a crystal, which affect the dislocations of the crystal. Based on the assumption that the crystal is elastic and isotropic, thermal stresses in a crystal are computed and the effects of operating conditions are investigated. The results show that the extreme thermal stresses are concentrated near the interface of a crystal and the radial and the tangential stresses are the dominant ones. Concentrated heating profile increases the stresses within the crystal, otherwise, the pulling rate decreases the stresses.

• Corrosion Science and Technology
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• 제22권1호
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• pp.36-43
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• 2023

Single-crystal Ni-rich NCM is a material that has drawn attention in the field of lithium-ion batteries due to its high energy density and long cycle life. In this study, we investigated the properties of single-crystal NCM 811 and its potential for use in lithium-ion batteries. High-quality single crystals of NCM 811 were successfully synthesized by crystal growth via a flux method. The single-crystal nature of the samples was confirmed through detailed characterization techniques, such as scanning electron microscopy and x-ray diffraction with Rietveld refinement. The crystal structure and electrochemical performances of the single-crystal NCM 811 were analyzed and compared to its poly-crystal counterpart. The results indicated that single-crystal NCM 811 had electrochemical performance and thermal stability superior to poly-crystalline NCM 811, making it a suitable candidate for high-performance batteries. The findings of this study contribute to a better understanding of the characteristics and potential of single-crystal NCM 811 for lithium-ion batteries.

• 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.375-398
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• 1996

A complex nonlinear optical crystal Cadmium Mercury Thiocyanate with size 18*18*20mm3 was grown. It possesses chemical stability below 247$^{\circ}C$, no cleavage, and high mechanical strength. Blue light second harmonic of diode laser was realized.