• Journal of the Korean Chemical Society
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• v.49 no.3
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• pp.283-287
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• 2005

• Journal of the Semiconductor & Display Technology
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• v.6 no.4
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• pp.33-38
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• 2007

Quartz glass panel was prepared by a colloidal silica through the heat-treatment only without any additives in wet-chemical method. This colloidal silica used in slurry process has the uniform distribution of particle size and lower cost. The results show that 6N as a degree of purity and the 86 percentage of violet transmittance in 1mm thickness. AFM(Atomic Force Microscopy) pattern shows that the surface roughness are less than lnm. Also, we investigated the characteristic of quartz panel according to the concentration and distribution of hydroxyl group, viscosity and thermal expansion coefficient.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.521-524
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• 2003

An effective purification method was developed for producing Homoharringtonine (HHT), to guarantee high purity and yield from Cephalotaxus koreana. This process was a simple and efficient procedure, for the isolation and purification of HHT form the biomass of Cephalotaxus koreana, consisting of extract, adsorbent treatment, precipitation and followed by a chromatography. The extraction, adsorbent treatment and precipitation in pre-purification process allows for rapid and efficient separation of HHT from many compound and dramatically increases the yield and purity of crude HHT for HPLC purification steps compared to alternative processes. This purification processes serves to minimize solvent usage, size, and complexity of the operations for HHT purification.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05e
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• pp.100-103
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• 2003

고휘도 LED(light emitting diode) 빨강(R), 녹색(G), 파랑(B), 호박색(A), 백색(W) 등의 중요한 광학특성인 광속(luminous flux), 효율(luminous efficacy), 피크 파장(peak wavelength), 가중치 평균 파장(weighted average wavelength), 반치폭 (full width at ha1f maximum), 색도좌표(chromaticity coordinate), 주 파장(dominant wavelength), 자극순도 (excitation purity) 와 휘도순도(colorimetric purity)에 대해서 비교검토하였다. 시험결과로 제시된 LED의 기본적인 특성 데이터는 추후, 새로운 조명용 LED 램프나 등기구(luminaire)를 개발 및 특성연구에 많은 도움을 줄 것으로 사료된다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.126-129
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• 2009

In this study, it was aimed to develop the re-use technology of ultra-fine silicon powders, by-products during the current production process of high purity poly-Si feedstock. For this goal, the compacts of the silicon powders were tried to fabricate by CIP (Cold Isostatic Pressing) method using silicon rubber mold without chemical binder materials. The density ratio of the silicon powder compacts reached 74%. In order to simulate the actual handling and charging conditions of feedstock material in casting process, a shaking test was carried out and mass loss measured. Finally, the silicon powder compacts were melted using a cold crucible induction melting method and the purity assessment was conducted by Hall effect measurement.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.261-264
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• 2007

In this study, the consolidation and casting processes of fine Si powders, by-products of making high purity Poly-Si rods in the current method, were systematically investigated for use as economical solar-grade feedstock. Morphology, size, and contamination type of the poly-Si fine powders were inspected by combined analysis of SEM, particle size analyzer, and FT-IR. Poly-Si powder compacts were tried to fabricate by a consolidation process without a binding agent and then their density ratio and strength were evaluated. Finally, the electrical resistivity of the specimens prepared by an electromagnetic casting method was examined for purity assessment.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.538-543
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• 2000

The purpose of this study is to develope electrostatic separation system for recycling of mixed waste plastics. The electrostatic separation system is designed and investigated the separation efficiency for separating of mixed waste plastics. Electrostatic separation system consisted of a tribocharger, separator (two electrode), collector (5 tray) and controller (positive/negative high voltage power supply). The tribocharger is a fluidized bed using tribo-electrification mechanism between particles and particles. In experimental results, the tribocharger of the fluidized bed was more effective separation efficiency. It showed the purity of $85{\sim}99\;%$ and the recovery of $80{\sim}98\;%$ from the powder of mixed plastics such as LDPE, HDPE, PP, PS, PET and PVC. Especially, In the separation experiment of Polyvinylchloride(PVC) which generates hazardous hydrogen chloride gas in case of the combustion. its purity was over 99 % and recovery was over 95 %.

• 보존과학연구
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• s.14
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• pp.45-76
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• 1993

Au-Cu alloyed coating layer were found by Hg-amalgam process and it seemed to be used Cu-amalgam process similar to Au-amalgam. Coated layer is dense and unique, Thickness of layer was 1.5 to $18.0\mum$ which had 95.3 to 99.8% purity of gold Matrix metal mostly cosists of forged copper alloy which had high purity and ferrite ($\alpha$) strusture. It showed excellent refining technical level at that time. Aowever, the nail, ferrous matrix used for strength needed, composed of silver foil packed and gold layer for adherence between ferrous matrix and gold layer

• Nuclear Engineering and Technology
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• v.47 no.5
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• pp.588-595
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• 2015

This study presents an effective method for additional recovery of residual actinides in liquid electrodes after the electrowinning process of pyroprocessing. The major distinctive feature of this method is a reactor with multiple reaction cells separated by partition walls in order to improve the recovery yield, thereby using the interelement difference in diffusion coefficients within the liquid electrode and controlling the selectivity and purity of element recovery. Through an example of numerical simulation of the diffusion scenarios of individual elements, we verified that the proposed method could effectively separate the actinides (U and Pu) and rare-earth elements contained in liquid cadmium. We performed a five-step consecutive recovery process using a simplified conceptual reaction cell and recovered 58% of the initial amount of actinides (U + Pu) in high purity (${\geq}99%$).

• Ceramist
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• v.9 no.6
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• pp.42-48
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• 2006

The structural ceramic, such as $A1_2O_3,\;ZrO_2\;and\;Si_3N_4$ have applied as several parts of precision machines, automotives and instruments for semiconductor. The mechanical properties depended on purity, morphology and microstructure of the ceramic and its fabrication process. High purity and fine starting powder for the structural ceramic was prepared mainly by wet process and powder processing such as milling, mixing, drying and granulating strongly influenced on the fabrication process. Powder processing included powder synthesis technology is essential for ceramic manufacture. Also, the advanced mechanical treat[neat in powder processing to create nano composite powder was developed to improve several properties of ceramic materials. Innovation of powder processing will lead to improve mechanical and functional properties of the ceramics.