• Toxicological Research
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• 제9권1호
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• pp.119-123
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• 1993

LBD-007, a newly developed recombinant human interferon ${\alpha}$A, was tested for primary eye and skin irritation in male New Zealand White rabbits. In the primary eye irritation test, 0.1ml of a solution of LBD-007 was instilled into the eye. In rinsing group, the eye was washed with water 30 seconds after instillation. No reaction was observed at the cornea, iris and conjunctivae by LBD-007. In the primary skin irritation test, LBD-007 was applied to the back of rabbits for 24 hours. Primary irritation index was "0" in test and control sites of all animals. Thus LBD-007 was evaluated as a non-irritant on the basis of the criteria of Draize et al.,(1994).

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 고액공존금속의 성형기술 심포지엄
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• pp.148-159
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• 1997

In this study, microstructure, size of primary $\alpha$, solid fraction and hardness of A356 Al alloy, were investigated. Semi-solid A356 allos were obtained by semi-solid continuous casting apparatus consists of melting furnace, formation apparatus of granular primary $\alpha$ and continuous casting apparatus. Size of promary $\alpha$ and fraction solid were decreased with decreasing temperature, and with increasing volume of cooling water. At the cooling water temperature of 15$^{\circ}C$ and cooling water volume of 18.2$\ell$/min, the sizes of primary $\alpha$ phases were decreased up to 40${\mu}{\textrm}{m}$, and fraction solid was 0.68.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 고액공존금속의 성형기술 심포지엄
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• pp.183-195
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• 1997

The micorstructural characteristics, particularly $\alpha$-halo formation, in semi-solid state processed hypereutectic Al-Si alloy was investigated. The microstructural changes during reheating of wedge type mold cast ingot, hot-rolled sheet, and Si particulate reinforced Al composite was compared with those occurred during stirring of semi-solid state hypereutectic alloy. In the case of semi-solid state reheating of wedge type ingot and hot-rolled sheet, fine particles of Si as well as $\alpha$-halo formed after heat treatment. Although there seemed to be no coarsening with variations of holding time, the region of $\alpha$-halo decreased due to homogenization. Nucleation and recrystallization was accelerated with the addition of alloying elements during hot rolling resulting in primary Si particle size decrease and $\alpha$-halo formation. In the case of extruded specimens, very little morphological change of reinforcing Si particles was observed. Almost no $\alpha$-halo formed during reheating because of the oxide film formed on the reinforcing Si particles which acted as a diffusion barrier between the matrix and the primary Si particles.

• 한국주조공학회지
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• 제18권6호
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• pp.541-549
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• 1998

Microstructural characteristics of hypereutectic Al-Si alloys during reheating at semi-solid temperature have been investigated. The size and morphology of primary Si particles in wedge-type mold-cast ingot has been compared with hot-rolled sheet and Si particulate reinforced Al composite. Effects of P and Sr addition on the morphological changes of primary Si particles have been also investigated. Observation of the solidification microstructures of the wedge-type mold-cast ingot at different cooling rates showed that alloying elements such as P and Sr affect the morphology of Si particles, especially in the area solidified at a slow cooling rate. Negligible change in the size of primary crystals was observed after reheating experiment, but ${\alpha}-halo$ formed around the Si particles and fine particles of Si precipitated in the surrounding area of the Si particles. In addition, there seemed to be no coarsening with increasing of holding time and the region of ${\alpha}-halo$ being decreased. Nucleation and recrystallization was accelerated with addition of alloying elements during hot rolling resulting in a decrease of primary Si particle size. In the case of extruded specimens, morphological change of primary Si particles was not observed after reheating. No ${\alpha}-halo$ formation was observed in Si reinforced Al composite because of the oxide film formed on the Si particles which acted as a diffusion barrier between substrate and the primary Si particles.

• 한국자동차공학회논문집
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• 제6권3호
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• pp.198-207
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• 1998

To determine the effect of temperature and microstructure on the fatigue crack propagation behavior in Ti-3Al-2.5V alloy, experimental investigations have been carried out with the specimens of different temperatures and different volume fractions of prime $\alpha$-phase. The temperatures employed were room temperature, 20$0^{\circ}C$, 30$0^{\circ}C$ and 40$0^{\circ}C$ under the same frequency of 20Hz. To obtain the different volume fractions of the primary $\alpha$-phase, specimens were solution-treated at $\alpha$+$\beta$ and above the $\beta$ region. From the experimental results, following conclusions were obtained. (1) ΔKth was observed to increase with the less volume fraction of the primary $\alpha$-phase. (2) As the temperature increased. (3) Microstructures having more primary $\alpha$-phase showed higher strength at the high temperatures.

• The Korean Journal of Physiology and Pharmacology
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• 제6권6호
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• pp.319-325
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• 2002

The induction of interleukin-6 (IL-6) using combined proinflammatory agents $(LPS/IFN-{\gamma}\;or\;TNF-{\alpha}/IFN-{\gamma})$ was studied in relation to p38 mitogen-activated protein kinase (MAPK) and $NF-{\kappa}B$ transcriptional factor in primary neonatal cardiomyocytes. When added to cultures of cardiomyocytes, the combined agents $(LPS/IFN-[\gamma}\;or\;TNF-{\alpha}/IFN-{\gamma})$ had stimulatory effect on the production of IL-6 and the elevation was significantly reduced by SB203580, a specific p38 MAPK inhibitor. SB203580 inhibited protein production and gene expression of IL-6 in a concentration-dependent manner. In this study, $IFN-{\gamma}$ enhancement of $TNF-{\alpha}-induced\;NF-{\kappa}B$ binding affinity as well as p38 MAP kinase activation was observed. However, a specific inhibitor of p38 MAPK, SB203580, had no effect on $TNF-{\alpha}/IFN-{\gamma}\;or\;LPS/IFN-{\gamma}-induced\;NF-{\kappa}B$ activation. This study strongly suggests that these pathways about $TNF-{\alpha}/IFN-{\gamma}$ or $LPS/IFN-{\gamma}-activated$ IL-6 release can be primarily dissociated in primary neonatal cardiomyocytes.

• 생태와환경
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• 제40권3호
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• pp.419-430
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• 2007

본 연구는 주암호, 동복호, 영산호 세 호소의 이화학적 인자, 식물플랑크톤 생체량(Chl ${\alpha}$) 및 일차생산력을 조사하기 위하여 2004년 4월부터 2006년 3월까지 총 8회에 걸쳐 계절별로 실시하였다. 소형식물플랑크톤이 우점(>60%)한 동복호의 식물플랑크톤 생체량은 상류에서 2004년 4월에 높았지만 하류에서는 2004년 6월에 높은 분포를 나타내었다. 주암호에서 식물플랑크톤 생체량이 높았던 2004련 4월에 미소형식물플랑크톤의 기여율이 높았다. 영산호는 8월 (2004, 2005)에 높은 생체량을 보였는데 이 시기 미소형식물플랑크톤의 기여율이 높았다. 일차생산력은 동복호, 영산호, 주암호 순으로 높게 분포되었다. 단순 회귀 분석결과, 동복호에서 젠체식물플랑크톤, 소형식물플랑크톤과 일차생산력은 투명도와 상관성을 보였다. 주암호에서는 하류에서 크기별 식물플랑크톤과 $PO_4^{3-}$가 상관성을 보였고 일차생산력은 수온, TN과 높은 상관성을 보였다. 영산호 상, 하류에서 식물플랑크톤은 TN/TP와 음의 상관성을 보였고 일차생산력은 상류에서 높은 상관성을 보였으나 하류에서는 탁도와 높은 상관성을 보였다. 주암호와 동복호는 기타 환경 인자와의 단순회귀분석결과로부터 인과 질소 관리의 필요성이 제기된다. 영산호는 부유물질을 관리할 필요성이 있고 하류의 높은 일차생산력으로 보아 식물플랑크톤의 내부생산 기여율에 대한 추가적인 조사를 통한 저감방안 마련도 필요한 것으로 사료된다.

• Transactions on Electrical and Electronic Materials
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• 제16권1호
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• pp.20-24
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• 2015

We studied the relationship between the surface smoothness of the internal Cu ribbon and the morphology of the Sn-Pb plating layer for solar cell modules. A bumpy surface was observed on the surface of the solar ribbon, which caused irregular reflection of light. Large, Pb-rich, primary ${\alpha}$-phases were found below the convex surface of the solar ribbon, passing from the surface of the internal Cu ribbon to the surface of the plating layer. The primary ${\alpha}$-phases heterogeneously nucleated on the convex surface of the Cu ribbon, and then largely grew to the convex surface of the plating layer. The restriction of the primary ${\alpha}$-phase's formation was enabled by enhancing the smoothness of the Cu ribbon's surface; it was also possible to increase the adhesive strength and decrease contact resistance. We confirmed that the solar ribbon's surface smoothness depends on the internal Cu ribbon's surface smoothness.

• Bulletin of the Korean Chemical Society
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• 제30권6호
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• pp.1293-1296
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• 2009

A new series of N-substituted 2-n-butyl-3-fluoropyrroles were prepared by a simple one-pot reaction designed of retrosynthesis. $\alpha,\alpha-Difluoro-\gamma-iodo-\gamma$-(trimethylsilyl)propyl n-butyl ketone, a component precursor molecule to 2-n-butyl-3-fluoropyrroles, was prepared with Cu(0) catalyst. It reacted with various primary amines to yield N-substituted 2-n-butyl-3-fluoropyrroles. The products were synthesized via a one-pot reaction scheme between $\alpha,\alpha-Difluoro-\gamma-iodo-\gamma$-(trimethylsilyl) propyl n-butyl ketone and primary amines in excess ( $\geq$ 5 molar equivalence), which eliminate the need of KF required in obtaining n-butyl-1H-3-fluoropyrrole. The yield of products depended reversely on spatial bulkness around N-binding carbon.

• 생태와환경
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• 제41권spc호
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• pp.21-26
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• 2008

본 연구는 $^{13}C$추적자를 사용하여 신구저수지 내 식물플랑크톤에 의한 1차 생산속도를 계산하고, $^{13}C$-GC/MS 기법을 사용하여 광합성을 통해 새롭게 만들어진 지방산의 생성속도를 분석하였다. 유광층 내의 SPM중 POM이 차지하는 비율은 약 76%였으며, 엽록소$-{\alpha}$의 평균 농도는 약 $89{\mu}g\;L^{-1}$이었다. 유광층 단위면적당 엽록소$-{\alpha}$ 총량, 1차 생산력, 엽록소$-{\alpha}$에 의한 탄소 고정 능력은 각각 112mg Chl-${\alpha}m^{-2}$, 3.53g C $m^{-2}\;d^{-1}$, 32mg C mg Chl-${\alpha}^{-1}\;d^{-1}$이었다. 수층 내 입자성유기물의 지방산 조성과 식물플랑크톤 광합성에 의해 새롭게 만들어진 입자성유기물의 지방산 조성이 거의 비슷한 것으로 미루어 보아, 본 연구기간 동안 수층의 입자성유기물은 대부분 식물플랑크톤에 의해 유래된 것으로 판단되었다. 또한 광합성을 통해 만들어진 유기물은 세포외배출 등의 과정을 통해 용존유기물 pool로 이동된 후 박테리아에게까지 빠르게 전달됨으로써, 박테리아에 의한 유기물 소비가 활발하게 일어나고 있는 것으로 판단된다.