• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.05a
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• pp.54-54
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• 2003

MgO layer는 POP 패빌 내 유전증을 이온의 스퍼터링으로부터 보호하여 주며, 또한 높은 이차 전자 밤출 계수의 특성을 가지고 있어 구동 및 유지 전압을 낮춰 주는 역할을 한다. 그러나. MgO layer는 $H_20,{\;}CO_2,{\;}N_2,{\;}0_2$ 그리고 $H_2$와 같은 불순물 들을 쉽게 를착하는 단점이 있어, PDP의 특성 및 수명 단축에 영향을 줄 수 있다. 따라서, 본 연구에서는 atmospheric pressure plasma cleaning 과 low pressure i inductively coupled plasma (ICP) cleaning 처리에 의하여, 보호층으로 사용이 되는 MgO layer의 outgassing 특성을 조사하고자 한다. plasma cleaning에 의한 MgO layer 표면의 roughness와 불순물의 변화를 알아보기 위 하여 atomic force microscopy(AFM)과 x-ray p photoelectron spectroscopy(XPS)를 이용하여 측정 하였다. 또한, outgassing의 특성을 분석하기 위하여 MgO layer를 $400^{\circ}C$ 까지 온도를 가하여 온도에 따른 outgassing의 특성을 quadrupole mass spectrometer(QMS)를 이용하여 알아보았다. atmospheric pressure plasma cleaning 에서는 $He/O_2/Ar/N_2$의 gas를 사용하였으며, low pressure ICP cleaning 에 서는 Ar의 gas를 사용하였다. atmospheric pressure plasma cleaning는 low pressure ICP C cleaning과 비교해 더 낮은 outgassing을 관잘 할 수 있었으나. MgO 표면의 roughness는 low pressure ICP cleaning 후 더 낮은 것을 알 수 있었다. 또한 $He/O_2/Ar/N_2$의 gas를 사용 한 atmospheric pressure plasma cleaning 과 $Ar/O_2$의 gas를 사용한 ICP cleaning에서 이 차전자방출계수(SEEC)가 약 1.5~2.5배 증가된 것을 알 수 있었다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.2
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• pp.69-73
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• 2010

The microstructural change of the $Sm_{0.5}Sr_{0.5}CoO_3$ (SSC) electrode for a cathode material of solid oxdie fuel cells (SOFCs) deposited by the electrostatic spray deposition (ESD) technique was characterized. Samarium chloride hexahydrate $(SmCl_3{\cdot}6H_2O)$, strontium chloride hexahydrate $(SrCl_2{\cdot}gH_2O)$, cobalt nitrate hexahydrate $(Co(No_3)_2{\cdot}6H_2O)$ as starting materials and methyl alcohol as solvent were used to make precursor solution. The suitable porous SSC films for a cathode of SOFCs were deposited on Si substrate and it is observed that the microstructure was strongly dependent on processing parameters such as deposition time, substrate temperature, and applied voltage. Scanning Electron Microscope (SEM) and X-ray Diffractometer (XRD) measurement were used to investigate the microstructure and crystallinity of the SSC films. The ESD technique is shown to be an efficient method in which the SOFCs' cathode film can be fabricated with the desired phases and microstructure.

• Korean Journal of Crystallography
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• v.1 no.2
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• pp.84-90
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• 1990

1,3-Diazatricyclo (5.2.1.Os .to) decane-2,11-dione , C8H10N2O2. MW=166.15, Monoclinic, P2/n a= 6.585(7) , b=9.089(4), c=12.937(10)A, β=95.72(5)˚, V=770.4A3, Z=4, Dc=1.43(4) g/cm3, λ (Mo Ka)=0.7093A, r=1.Ocm-1, T=295˚K, final R=0.037 for 698 unique observed reflections. The compound is the product of the intramolecular (2+2) photocycloaddition of Nl-(w-butenyl)uracil and belongs to a (5.2.1.O5.10) tricyclic system. A pair of molecules related by the inversion symmetry are held together by the strong hydrogen bonding interactions between 02 and H3 of the uracil moiety.

• Corrosion Science and Technology
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• v.15 no.3
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• pp.125-128
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• 2016

The ASTM T92 steel was corroded at $600^{\circ}C$ and $800^{\circ}C$ at 1 atm of $N_2/3.1%H_2O/2.42%H_2S-mixed$ gas. The formed scales were thick and fragile. They consisted primarily of the outer FeS scale and the inner (FeS, $FeCr_2S_4$)-mixed scale containing a small amount of the $Cr_2O_3$ scale. This indicated that corrosion occurred mainly via sulfidation rather than oxidation due to the $H_2S$ gas. Since FeS was present throughout the whole scale, T92 steel was non-protective, displaying high corrosion rates.

• Resources Recycling
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• v.26 no.6
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• pp.38-44
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• 2017

As by-pass dust (BPD) made from cement manufactured process is designated waste, it is required to bury as high cost. The main component of BPD is potassium chloride (KCl), and used for the fertilizer. For using KCl to the fertilizer, the pH value of KCl is required as neutral or weak acid. However, it is not suitable to apply BPD into the fertilizer directly without any other treatment because BPD's pH value is shown 12.0~12.5; a high base. In this study, the carbon dioxide ($CO_2$) was used for removing calcium oxide (CaO) and reducing pH value during manufacturing process of KCl. We fixed inner condition of the carbon test chamber as $25^{\circ}C$-50RH%, and retained 0~7 hours under the 20 vol% of $CO_2$ atmosphere. After experiment, we analyzed the content of CaO and pH value from each samples. The more time exposed to $CO_2$, the content of CaO and pH value are shown. Furthermore, pH value exposed in 6 hours nearly reached 7.

• Journal of Hydrogen and New Energy
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• v.26 no.5
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• pp.423-430
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• 2015

$Cu/ZnO/Al_2O_3$ catalysts for water gas shift (WGS) reaction were synthesized by co-precipitation method with the fixed molar ratio of Cu/Zn/Al precursors as 45/45/10. Copper and zinc precursor were added into sodium carbonate solution for precipitation and aged for 24h. During the aging period, aluminum precursor was added into the aging solution with different time gap from the precipitation starting point: 6h, 12h, and 18h. The resulting catalysts were characterized with SEM, XRD, BET surface measurement, $N_2O$ chemisorption, TPR, and $NH_3$-TPD analysis. The catalytic activity tests were carried out at a GHSV of $27,986h^{-1}$ and a temperature range of 200 to $400^{\circ}C$. The catalyst morphology and crystalline structures were not affected by aluminum precursor addition time. The Cu dispersion degree, surface area, and pore diameter depended on the aging time of Cu-Zn precipitate without the presence of $Al_2O_3$ precursor. Also, the interaction between the active substance and $Al_2O_3$ became more stronger as aging duration, with Al precursor presented in the solution, increased. Therefore, it was confirmed that aluminum precursor addition time affected the catalytic characteristics and their catalytic activities.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.359-359
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• 2009

투명전도 산화막 재료로 널리 사용되고 있는 ITO는 전기적 및 광학적 특성이 우수한 장점이 있으나, ITO의 주 재료인 인듐은 매장량이 적어서 가격이 고가인 단점이 있어 대체 재료의 개발이 시급한 상황이다. ITO 대체 TCO로 가장 유력한 후보인 Al doped ZnO(AZO)는 가시광을 투과하는 성질을 가지고 있고, 저온 공정이 가능하다는 장점뿐만 아니라 수소 분위기의 안정성 및 가격이 싸다는 장점이 있다. 본 연구에서는 양이온 금속원소(Al)과 음이온 할로겐 원소(F) 및 수소(H)를 co-doping한 ZnO 박막을 rf 마그네트론 스퍼터를 이용하여 증착한 뒤 도핑량과 진공중에서의 열처리에 따른 전기적 및 광학적 특성에 대해 고찰하였다. Al과 H를 co-doping한 ZnO의 박막의 경우 Al의 농도가 낮은 TCO박막이 전기적 특서에서 더 큰 향상을 보였으며, 동일한 F 함량에서는 H 함량이 늘어날수록 캐리어의 증가해 TCO박막의 전기적 특성이 향상되는 것으로 나타났다. 그러나 진공중의 열처리에 따른 F와 H의 거동은 반대로 나타났다. 이 연구를 통해서 $36.2cm^2$/Vs의 높은 홀 이동도와 $2.9{\times}10^{-4}{\Omega}cm$의 낮은 비저항을 가지는 ZnO계 박막의 제조가 가능하였다.

• Korean Journal of Materials Research
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• v.28 no.8
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• pp.466-473
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• 2018

Nickel oxide(NiO) thin films, nanorods, and carbon nanotube(CNT)/NiO core-shell nanorod structures are fabricated by sputtering Nickel at different deposition time on alumina substrates or single wall carbon nanotube templates followed by oxidation treatments at different temperatures, 400 and $700^{\circ}C$. Structural analyses are carried out by scanning electron microscopy and x-ray diffraction. NiO thinfilm, nanorod and CNT/NiO core-shell nanorod structurals of the gas sensor structures are tested for detection of $H_2S$ gas. The NiO structures exhibit the highest response at $200^{\circ}C$ and high selectivity to $H_2S$ among other gases of NO, $NH_3$, $H_2$, CO, etc. The nanorod structures have a higher sensing performance than the thin films and carbon nanotube/NiO core-shell structures. The gold catalyst deposited on NiO nanorods further improve the sensing performance, particularly the recovery kinetics.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.62-67
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• 2012

A series of homo binuclear complexs of the type $[M_2(L/L^')(NO_3)n].mH_2O$, [where $M=U{O_2}^{2+},\;Th^{4+},\;ZrO^{2+}$] and $[(VO)_2(L/L^')(SO_4)_2]{\cdot}2H_2O$, L=1,5,6,9,12,15,16,20 octaaza-7,813,14-tetraphenyl-2,4,17,19-tetramethyl-1,4,6,8,12,14,16,19-docosaoctene (OTTDO) or L'=10:11;21:22-dibenzo-1,5,6,9,12,15,16,20-octaaza-7,813,14-tetraphenyl-2,4,17,19-tetramethyl-1,4,6,8,12,14,16,19-docosaoctene (DOTTOT), n=4 for $U{O_2}^{2+}$, $ZrO^{2+}$ n=8 for $Th^{4+}$ m=1,2,3 respectively, have been synthesized in template method from ethylenediamine/orthophenylene diamine, benzil monohydrazone and acetyl acetone and characterized on the basis of elemental analysis, thermal analysis, molar conductivity, magnetic moment, electronic, infrared, $^1H$-NMR studies. The results indicate that the VO(IV) ion is penta co-ordinated yielding paramagnetic complexes; $UO_2(VI)$, ZrO(IV) ions are hexa co-ordinated where as Th(IV) ion is octa co-ordinated yielding diamagnetic complexes of above composition. The fungi toxicity of the ZrO(IV) and VO(IV) complexes against some fungal pathogen has been studied.

• Herbal Formula Science
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• v.10 no.2
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• pp.243-249
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• 2002

This study was performed to investigate the effects of fermented extract of Pinus densiflora (FPD) on oxygen radicals and $H_2O_2$-induced damage. The results are as follows: 1. The 1.1-diphenyl-2-picrylhydrazyl (DPPH) free radicals were considerably reduced by FPD and $IC_{50}$ value was showed the concentration of 20 ㎍／㎖. 2. The cytotoxicity did not observe by FPD treatment in A548 cells. 3. The $H_2O_2$-induced cell damage was recovered by FPD pretreatment in A549 cells. These results suggest that FPD, as a natural antioxidant, has scavenging effect of free radicals and protection effect from $H_2O_2$-induced cytotoxicity.