• 대한기계학회논문집A
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• 제27권7호
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• pp.1051-1057
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• 2003

This study is about controlled impurities, which make metal alloys, especially AC4CH alloy that is made by restraining 0.2％ Fe and Aluminum to make a matrix material. A metal matrix composite is produced using the squeeze casting method. The first step in the squeeze casting method is to add some organic binder including aluminum borate whisker into the matrix. After the fabrication of a metal matrix composite, each is individually appended to an inanimate binder such as SiO$_2$, Al$_2$O$_3$, and TiO$_2$. Through experiments the mechanical property changes were investigated between the metal matrix composite and AC4CH alloy. This study proves the superiority of the mechanical property of a metal matrix composites over AC4CH according to the previous tests and results that were mentioned above. One excellent property of matrix material composites is the infiltrated TiO$_2$ reinforcement. This material is a good substitute for the existing materials that are used in the development of industries today.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.198-203
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• 2001

This study is about controlled impurities, which make metal alloys, especially AC4CH alloy that is made by restraining 0.2% Fe and Aluminum to make a matrix material. A metal matrix composite is produced using the squeeze casting method. The first step in the squeeze casting method is to add some organic binder including aluminum borate whisker into the matrix. After the fabrication of a metal matrix composite, each is individually appended to an inanimate binder such as $SiO_2,\;Al_2O_3$, and $TiO_2$. Through experiments the mechanical property changes were investigated between the metal matrix composite and AC4CH alloy. This study proves the superiority of the mechanical property of a metal matrix composites over AC4CH according to the previous tests and results that were mentioned above. One excellent property of matrix material composites is the infiltrated $TiO_2$ reinforcement. This material is a good substitute for the existing materials that are used in the development of industries today.

• 분석과학
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• 제27권1호
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• pp.11-21
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• 2014

금강의 퇴적물 중에 입도, 유기물 그리고 금속류 분포를 2011년도 2계절에 걸쳐 조사하였다. 퇴적물 시료는 강어귀에서 채취하여 금속류와 입도 등 일반지표항목을 측정하였다. 금속류(Pb, Zn, Cu, Cr, Ni, As, Cd, Hg, Al, Li)는 유도프라즈마 분광기로 측정하였고 유기물은 강열감량으로 그리고 입도는 다른 망 크기의 체를 사용하여 결정하였다. 서로간의 상관성 분석이 이루어졌고 피어슨 상관계수를 사용하여 상관성을 나타내었다. 분석결과 건기에 금속류가 보다높은 농도로 검출되었다. 금속류의 농도는 유기물의 함량과 상관성이 높았고 이는 금속류가 유기물에 용해되어 높아질 수 있음을 보여주는 결과이다.

• 동아시아식생활학회지
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• 제16권4호
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• pp.468-473
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• 2006

This study was conducted to develop pigment of flowers as a food material and the red rose(Rosa hybrida L.) was used for this study. To check the possibility of using the rose pigment as a food additive we have extracted the pigment from rose and examined all the factors (pH, temperature, free sugars, organic acids, metal ions) for stability. The results obtained are as follows: In examining the stability of the pigment, the residue of the pigment noticeably decreased with the increase of the pH and the temperature, and among free sugars (fructose, glucose, sucrose) the addition of fructose made the residue the lowest. With the addition of organic acids the samples exhibited the hyperchromic effect throughout the period of the storage. The pigment residue decreased when the amount of the metal ions increased and especially the Cu$^{2+}$ ion was most destructive.

• 한국전기전자재료학회논문지
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• 제18권6호
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• pp.582-586
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• 2005

We have grown GaN layers with in-situ SiN mask by metal organic chemical vapor deposition (MOCVD) and study the physical properties of the GaN layer. We have also investigate the effect of the SiN mask on its optical property. By inserting a SiN mask, (102) the full width at half maximum (FWHM) decreased from 480 arcsec to 409 arcsec and threading dislocation (TD) density decreased from $3.21\times10^9\;cm^{-2}\;to\;9.7\times10^8\;cm^{-2}$. The PL intensity of GaN with SiN mask improved 2 times to that without SiN mask. We have thus shown that the SiN mask improved significantly the physical and optical properties of the GaN layer.

• 환경위생공학
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• 제9권2호
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• pp.110-119
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• 1994

The objective of the this study was to evaluate the effects of heavy metals on the sewage treatment process designed to remove organic material and nutrients using Water- hyacinth ( Eichhornia crassipes ). Batch experiments were carried out using domestic sewage spiked with different level of heavy metal mixtures ( Cd, Pb and Cu ). The specific growth rates of Water- hyacinth ranged from 0.0008 to 0.0015 1/day( operated at water temperatures of 22 ∼30$\circ $c ) and increased as the concentration of heavy metals decreased. The test result showed that the permissible maximum concentrations Cd, Pb and Cu for the growth of Water- hyacinth were 0.5, 1, and 6 mg/ℓ respectively. Under these maximum permissible heavy metal loads, removal rate of organic material, nitrogen and phosphorus were 85%,75% and 75% , respectively, during 40days of the test period.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.47-47
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• 2007

Indium oxide conducting films were dep9sited on Si(100) substrates at various temperatures by liquid delivery metal organic chemical vapor deposition using Indium (III) tris (2,2,6,6-tetramethyl-3.5-heptanedionato) $(dpm)_3$ precursors. The films deposited at $200{\sim}400^{\circ}C$ were grown with a (111) preferred orientation and exhibit an increase of grain size from 21 to 33nm with increasing deposition temperature. In the range of deposition temperature, there is no metallic indium phase in deposited films.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2009년도 Korea Superconductivity Society Meeting 2009
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• pp.81-81
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• 2009

• 한국염색가공학회지
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• 제26권4호
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• pp.277-282
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• 2014

Two tert-butyl substituted phthalocyanines(Pcs), in metal-free and metallated forms, were synthesized and the fluorescence responses toward various nitro derivatives, including picric acid(PA), 2,4-dinitrotoluene(DNT), 1,4-dinitrobenzene(DNB), 4-nitrotoluene(NT), nitrobenzene(NB), 1,4-benzoquinone(BQ), and nitromethane(NM) were investigated. Among the various nitro derivatives, current Pc derivatives exhibited efficient and exclusive fluorescence quenching in the presence of picric acid, which was readily observed by a naked eye. Quenching efficiency was estimated by the Stern-Volmer relationship, in which quenching constant, KSV, was calculated to be in the range of $10^4M^{-1}$. It was also found out that the aggregational behaviors of these Pcs are heavily dependent on the nature of solvent systems, subsequently affecting the quenching efficiency.

• 유기물자원화
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• 제11권2호
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• pp.97-109
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• 2003

본 연구는 폐수배출업소의 오니를 비료관리법의 비료공정규격에 퇴비원료로 활용 가능성을 조사하기 위하여 수행하였다. 수도의 정수장오니는 일부 중금속 성분이 높은 것이 발견되었으나 대부분 중금속 성분이 기준에 미달되었다. 그러나 유기물 성분이 기준에 비해 상당히 낮아 퇴비의 원료로 활용은 어려울 것으로 보였으며 기타 농업적 활용에 대해 연구 검토하는 것이 바람직할 것으로 생각되었다. 섬유 및 가죽 폐수처리 오니는 제조공정 특성상 유기물 및 중금속 성분이 기준에 미달될 가능성이 많았으므로 퇴비원료로 활용은 곤란할 것으로 판단되었다. 화장품 폐수처리오니는 일부 중금속 성분이 기준에 미달될 우려가 있었으므로 원료 및 공정 등을 검토하여 선별적으로 활용하는 것이 바람직할 것으로 예상되었다.