• Journal of the Korean Chemical Society
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• v.41 no.4
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• pp.175-179
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• 1997

Luminescence of $Eu^{3+}$ has been studied in $Sr_{2-2x}Eu_xK_xSnO_4$ with two-dimensional $K_2NiF_4$ structure. The $^5D_o$ → $^7F_o$$Eu^{3+}$ ion represents the J=0 → J=0 transition which is forbidden by a Judd-Ofelt selection rule for electric dipole transition in 4f shell of $Eu^{3+}$ ions. However, the emission line of $^5D_o$ → $^7F_o$$Eu^{3+}$ emission spectra of Sr2-2xEuxKxSnO4$Sr_{2-2x}Eu_xK_xSnO_4$structure around $Eu^{3+}$ ions.

• Clean Technology
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• v.29 no.4
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• pp.327-332
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• 2023

This study investigated synthesis gas production via steam reforming of biogas. Ni-Al₂O₃ and Ni-CeO₂ catalysts were synthesized using the co-precipitation method, with controlled precipitation agent injection rates. Catalytic performances were tested at various temperatures, with a gas composition ratio of CH₄:CO₂:H₂O = 1:0.67:3 and a gas hourly space velocity (GHSV) of 647,000 mL h^-1 gcat^-1. The rate of precipitation agent injection influenced the characteristics of the catalysts depending on the type of support used. As the temperature increased, both the CO₂ reforming of methane and the reverse water gas shift reactions occurred. The Ni-Al₂O₃ catalyst, synthesized with a single injection of the precipitation agent, exhibited the best catalytic activity under conditions with sufficient steam supply among the prepared catalysts, due to its high Ni dispersion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.180-180
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• 2010

본 연구에서는 P-Type의 NiO를 Glass기판의 ITO전극위에 RF-스퍼터링 방법으로 증착하였으며, NiO 완충층의 두께 변화에 따른 OLED (Organic Light Emitting Diode) 소자의 발광 특성에 대해 연구하였다[1, 2]. NiO는 우수한 전기 광학적 특성을 가지고 있어 OLED소자의 구동전압, 발광 효율 등의 특성을 향상 시킬 수 있다[3]. NiO 완충층의 두께 변화는 스퍼터링 증착시간을 통해 5-20 nm로 조절하였으며 소자의 구조는 Glass/ITO/NiO(0~20nm)/NPB(40nm)/Alq3(60nm)/LiF(0.5nm)/Al(120nm)형태로 제작하였다. ITO/NPB 계면에 NiO 완충층을 삽입함으로써 OLED 발광소자의 구동전압을 ~8V에서 ~5V (NiO, 10nm)로 낮출 수 있었다.

• Bulletin of the Korean Chemical Society
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• v.26 no.7
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• pp.1029-1030
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• 2005

• Journal of the Korean Ceramic Society
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• v.55 no.4
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• pp.358-363
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• 2018

To improve the polarization property of cathodes, which is the main factor limiting the performance of protonic ceramic fuel cells (PCFCs), $K_2NiF_4-type$ $Pr_2NiO_{4+{\delta}}$, which is expected to exhibit a triple conducting property (proton, oxygen ion, and hole conductions) was applied to PCFCs and its properties were investigated. Low-temperature microwave heat-treatment was used to achieve both sufficient interface adhesion between the electrolyte and the cathode layers and suppression of the secondary phase formation due to migration of elements such as barium and cerium. Through this fabrication method, a high performance of $0.82W{\cdot}cm^{-2}$ and low ohmic resistance of $0.06{\Omega}{\cdot}cm^2$ were obtained in an $Ni-BaCe_{0.55}Zr_{0.3}Y_{0.15}O_{3-{\delta}}$ | $BaCe_{0.55}Zr_{0.3}Y_{0.15}O_{3-{\delta}}$ | $Pr_2NiO_{4+{\delta}}$ single cell at $650^{\circ}C$. This result verifies that the $K_2NiF_{4+{\delta}}-type$ cathode shows good chemical compatibility which, in turn, will make it a potent candidate as a PCFC cathode.

• Journal of Mechanical Science and Technology
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• v.16 no.7
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• pp.911-918
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• 2002

The tribological performance of A1$_2$O$_3$/NiCr coating deposited on steel (SH45C) was investigated under lubrication. The parameters of sliding wear consist of normal load and coating thickness. Test result showed that there was no evidence of an improved bonding strength in the coating. However, the wear resistance of the A1$_2$O$_3$/NiCr coaling was significantly greater than that of the Al$_2$O$_3$ coating. It was eviclent that the residual stress for the A1$_2$O$_3$coating was higher than that of the A1$_2$O$_3$/NiCr coating from the Scratch test failure of coating. The bond coating played an important role in decreasing the residual stress. Also, it was found that the residual stress had d notable influence on the wear mechanism.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.7 s.166
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• pp.1245-1252
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• 1999

The sliding wear behavior of $Al_2O_3/NiCr$ coating deposited on steel(SM45C) was investigated under lubrication. The parameters of sliding wear are normal loads, coating thickness. As a result, the wear resistance of $Al_2O_3/NiCr$ coating was remarkably greater than that of $Al_2O_3$ coating. The optimized coating thickness was found to be $300{\mu}m$ to ensure good anti-wear. The bond coating played important role in decreasing residual stress. The residual stress had much influence on wear mechanism. These results were correlated with the stress state of coating and the microstructure of coating.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.799-802
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• 2003

[ $LaNiO_3$ ](LNO) thin films were deposited on various substrates as Si and $Al_2O_3$ by sol-gel process using lanthanum nitrate and nickel acetate. The structure and orientation of the films were characterized by X-ray diffraction. The orientation factors of films on Si(100), Si(111), $SiO_2/Si(100)$ and $Al_2O_3$were 97%, 63%, 73%, and 24% respective. The conductivity was $7.6{\times}10^{-3}{\Omega}{\cdot}cm$ with 10 times coating at Si(100) substrate.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.518-522
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• 2013

Cyclohexanone is important intermediate for the manufacture of caprolactam which is monomer of nylron. Cyclohexanone is generally produced by dehydrogenation reaction of cyclohexanol. In this study, highly mesoporous metal oxides such as meso-$WO_3$, meso-$TiO_2$, meso-$Fe_2O_3$, meso-CuO, meso-$SnO_2$ and meso-NiO were synthesized using mesoporous silica KIT-6 as a hard template via nano-replication method for dehydrogenation of cyclohexanol. The overall conversion of cyclohexanol followed a general order: meso-$WO_3$ >> meso-$Fe_2O_3$ > meso-$SnO_2$ > meso-$TiO_2$ > meso-NiO > meso-CuO. In particular, meso-$WO_3$ significantly showed higher activity than the other mesoporous metal oxides. Therefore, the meso-$WO_3$ has wide range of application possibilities for dehydrogenation of cyclohexanol.

• Journal of the Korean Ceramic Society
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• v.23 no.6
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• pp.52-58
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• 1986

$Pb(Zr_{0.525} Ti_{0.475})O_3$ piezoelectric ceramics both unmodified and doped with NiO were prepared by the conventional oxide techniques using sintering temperature from 900 to to 125$0^{\circ}C$. The difference in densification process between unmodified and NiO doped PZT ceramics was studied by shrinkage vs. firing temperatures and it was caused by increasing defect concentration in calcining process of NiO doped PZT ceramics. And nickel oxide solubility limit for $Pb(Zr_{0.525} Ti_{0.475})O_3$ ceramics is shown to be at the range from 0.2wt% to 0.5wt% from this defect model micro-structures dielectric and piezolectric properties of Nio doped PZT ceramics.