• 공업화학
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• 제27권2호
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• pp.195-198
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• 2016

DMT 생산과정의 부산물로서 폐기 처리되어 왔던 MFB를 출발 물질로 하여 고급 형광증백제 중의 하나인 4,4'-bis(2-benzoxazolyl)stilbene (BBS) 합성을 4단계를 거쳐 총 수율 73%의 경쟁력 있는 공정개발을 수행하였다. 제시된 합성법은 MFB와 ethyl 4-((diethoxyphosphoryl)methyl)benzoate (1)과 반응시킨 후, coupling 생성물 4,4'-stilbenedicarboxylate (2)를 얻고 이를 4,4'-stilbenedicarbonyl chloride (3)으로 변환 후 BBS 합성의 핵심 단계인 benzoxazole 형성 단계에서 상용화가 가능한 용매와 촉매를 탐구하여 용매로는 1,2,4-trichlorbenzene 촉매로는 boric acid의 사용이 가능한 것을 확인하였다.

• 반도체디스플레이기술학회지
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• 제9권2호
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• pp.33-39
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• 2010

The moisture absorption properties such as diffusion coefficient and moisture content ratio of liquid type epoxy resin systems with the filler were investigated. Bisphenol A type and Bisphenol F type epoxy resin, Kayahard MCD as hardener and 2-methylimidazole as catalyst were used in these epoxy resin systems. The nano-sized spherical type fused silica as filler were used in order to study the moisture absorption properties of these liquid type epoxy encapsulant according to the change of filler size. The temperature of glass transition (Tg) of these epoxy resin systems was measured using Dynamic Scanning Calorimeter (DSC), and the moisture absorption properties of these epoxy resin systems according to the change of time were observed at $85^{\circ}C$ and 85% relative humidity condition using a thermo-hygrostat. The diffusion coefficients in these systems were calculated in terms of modified Crank equation based on Ficks' law. An increase of Tg and diffusion coefficient with filler size in these systems can be observed, which are attributed to the increase of free volume with Tg. The change of maximum moisture absorption ratio according to the filler size and filler content cannot be observed; however, the diffusion coefficients of these systems decreased with filler content. The diffusion via free volume is dominant in the epoxy resin systems with low nano-sized filler content; however, the diffusion with the interaction of absorption according the increase of the filler surface area is dominant in the liquid type epoxy encapsulant with high nano-sized filler content.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.727-730
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• 2009

Highly active and stable nano-sized Ni catalysts supported on MgO-$Al_2O_3$ calcined from hydrotalcite-like materials have been successfully developed with a strong metal to support interaction (SMSI) to enhance the coke resistance in combined $H_2O$ and $CO_2$ reforming of $CH_4$ (CSCRM) for syngas ($H_2$/CO=2) production. The change of the surface area and NiO crystallite size with varying the pre-calcination temperature of support and Mgo content was investigated in relation to the coke resistance. As increasing the pre-calcination temperature, the surface area decreases and the metal to support interaction becomes weak. As a consequence, the coke deposition was more severe on catalysts pre-calcined at high temperature. It was concluded that highly dispersed Ni metal in the surface of Ni/MgO-$Al_2O_3$ catalyst (MgO=30 wt%) pre-calcined at $800^{\circ}C$ had a strong metal to support interaction (SMSI) resulting in an increase of coke resistance and high activity.

• 한국전기전자재료학회논문지
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• 제18권9호
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• pp.787-792
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• 2005

Chemical mechanical polishing(CMP) has become the process of choice for modem semiconductor devices to achieve both local and global planarization. CMP is a complex process which depends on numerous variables such as macro, micro and nano-geometry of pad, relative velocity between pad and wafer stiffness and dampening characteristics of pad, slurry, pH, chemical components of slurry, abrasive concentration, abrasive size, abrasive shape, etc. Especially, an oxidizer of chemical components is very important remove a target material in metal CMP process. This paper introduces the effect of oxidizer such as $H_2O_2,\;Fe(NO_3)_3\;and\;KIO_3$ in slurry for tungsten which is used in via or/and plug. Finally the duplex reacting mechanism of $oxidizer(H_2O_2)$ through adding the $catalyst(Fe(NO_3)_3)$ could acquire the sufficient removal rate in tungsten CMP.

• 한국수소및신에너지학회논문집
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• 제27권4호
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• pp.341-348
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• 2016

The experiments related on structure and water electrolysis performance of HALE UAV stack were conducted in this study. Anode catalyst $IrRuO_2$ was prepared by Adam's fusion methods as 2~3 nm nano sized particles, and the cathode catalyst was used as commercial product of Premetek. The MEA (membrane electrode assembly) was manufactured by decal methods, anode and anode catalytic layers were prepared by electro-spray. HALE stack was composed of 5 multi-cells as $0.2Nm^3/hr$ hydrogen production rate with hydrogen pressure as 10 bar. The water electrolysis performance was investigated at atmospheric pressure and temperature of $55^{\circ}C$. Best performance of HALE UAV stack was recorded as cell voltage efficiency as 86%.

• 한국전기전자재료학회논문지
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• 제29권4호
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• pp.247-249
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• 2016

In this study, we investigated the color change of the normal light gray granite as the high value color granite. By coating the metal catalyst liquid on the surface of granite stone, the metal particles were penetrated into the granite and the color of granite was changed permanently through the annealing treatment. To increase penetration depth into the granite, we used DC (direct current) bias. Two kinds of bias were used such as DC bias and pulse DC bias. And the penetration time was changed as 30 and 60 min. In all cases, the color granite were successfully obtained. Regardless of the catalyst reaction time, the penetration depth was increased by using the bias treatment. We obtained a penetration depth of 21 mm with the DC pulse bias during 60 min.

• 공업화학
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• 제17권6호
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• pp.648-652
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• 2006

$MnO_{2}$는 배터리, 촉매 및 capacitor 등의 사용으로 인하여 이의 수요는 날로 증가하고 있다. 본 연구는 sacrificial core 법을 이용하여 $MnO_{2}$ 중공 미세구를 제조하였다. 이때 $MnO_{2}$ 나노입자는 manganese acetate의 가수분해 및 축합반응에 의해 제조되었다. 실험결과 물 0.2%, manganese acetate 0.65 mM, 촉매 0.02 mM를 실온에서 반응시켜 실험을 하였을 때 일정한 모양의 $MnO_{2}$ hollow microsphere를 제조할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1127-1130
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• 2013

Formation of the monodisperse submicrospheres consisting of ionic palladium(II) complexes, $[(Me_4en)Pd(L)]_2(X)_4$($Me_4en$ = N,N,N',N'-tetramethylethylenediamine; L = bis(4-(4-pyridylcarboxyl)phenyl)methane; $X^-=BF_4{^-}$ and $ClO_4{^-}$), has been carried out without any templates or additives. The submicrospheres were coated with silicates, and then calcined in air at $550^{\circ}C$ for 1 h, to efficiently form hollow-spherical $SiO_2$ submicro-reactors dotted with palladium(0) nanoparticles (PdNPs). That is, the submicrospheres act as both a template and a source of the palladium metal nanoparticles. The submicro-reactors containing nano-catalysts have been characterized by means of SEM, TEM, and XPS. Notably, the reactors were proved to be very effective for Suzuki-Miyaura cross-coupling and hydrogenation reactions.

• Journal of Electrochemical Science and Technology
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• 제1권1호
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• pp.10-18
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• 2010

Controlled electrodeposition of dendritic nano-structured gold-platinum (AuPt) alloy onto an electrochemically pretreated carbon paper substrate was conducted in an attempt to improve catalyst utilization and to secure an electronic percolation network toward formic acid (FA) fuel cell application. The AuPt catalysts were obtained by potentiostatic deposition. AuPt catalysts synthesized as bimetallic alloys with 60% Au content exhibited the highest catalytic activity towards formic acid electro-oxidation. The origin of this high activity and the role of Au were evaluated, in particular, by XPS analysis. Polarization and stability measurements with 1 mg $cm^{-2}$ AuPt catalyst (only 0.4 mg $cm^{-2}$ Pt) showed 52 mW $cm^{-2}$ and sustainable performance using 3M formic acid and dry air at $40^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1445-1453
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• 2013

$Zn_{(1-x)}Ni_xAl_2O_4$ (x = 0.0-1.0) spinels were prepared at $800^{\circ}C$ by co-precipitation method and characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. The specific surface area was determined by BET. SEM image showed nano sized spherical particles. XPS confirmed the valence states of the metals, showing moderate Lewis character for the surface of materials. The powders were successfully used as new heterogeneous catalysts of Biginelli's reaction, a one-pot three-component reaction, leading to some dihydropyrimidinones (DHPMs). These new catalysts that produced good yields of DHPMs, were easily recovered by simple filtration and subsequently reused with persistent activity, and they are non-toxic and environmentally friendly. The optimum amount of catalyst is 20% by weight of benzaldehyde derivatives, while the doping amount has been found optimal for x = 0.1.