• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.1164-1167
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• 2003

Recently CRT is getting flatted, As change of CRT trend from normal type to Flat type, the material of Shadow Mask was also changed from AK(Aluminum Killed) to Invar(Fe-Ni alloy) materials Until now we have used just AK(Aluminum Killed) for normal type TV(not flat type), but main raw material of shadow mask component was changed. . However recently Invar(Fe-Ni alloy) materials, which has advantage of Low Thermal Expansion and High Strength, has been developed as well as applying in mass production as CRT's trend has become more flat and fine pitch. As main raw material of shadow mask component was changed, conditions of process were changed. One of them, the importance of pre-etching process (assistant process for developing & etching) is improved because there are so many particles in the pre-etching bath because of Ni compounds. Since the solubility of Ni in pre-etching solvent is very low related to Fe's, so the compounds of Ni happen to make particles.(the solubility of Fe is twenty times Ni's) that particles happen to make process troubles and NG productions so to clear the particles we had to established high cost filtering system, but it is useless. As time goes by the quantity of particles (Ni compounds) was increased because of the capability of filtering system was not enough, the particles was produced continuous in bath, and it make quality problems. Hence we tried to develop the new pre-etching solution to remove the particles (Ni compounds) and to cost down the filtering system's running cost. But in improving the solution we discovered the new pre-etching solution made the PR developing better. In former solution there were three kinds of chemistry (COOH)2 , H2O2 , H2S04 .first the function of (COOH)2 is drilling the surface of Invar, during this mechanism Ni compounds occurred. Second the function of H202 is removing the PR fringe (half UV exposure zone on PR(PVA)), Third the function of H2S04 is the catalysis of (COOH)2 In those, (COOH)2 was the main reason to make the Ni compounds. So to improve the solutions we had to change (COOH)2 to the other material. the chemistry we improved was a complex chemistry based on H2S04 . after using this chemistry the particles problem was disappeared and there was another advantage cut down the PR fringe. The New solution made the function of H202 better so the PR developing improved. To be direct the catalyst of the new solution helped the H202. anyway First thing after change the solution the quality of shadow Mask for flat color TV was improved & the yield also improved. But the more important thing is how to control the new solution. So we accepted the new concept which was the degree of freshness. The degree of freshness is based on non-reacted solution which was 100% ( the degree of freshness) and calculated the melted Ni quantity as time goes by. So we made the gauging liner plot. In conclusion, many companies tried to make fine pitched Shadow Mask ,generally to make quality jump up it needed a lot of cost & persons .in this case the shift of core material made it possible.

• 마이크로전자및패키징학회지
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• 제9권4호
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• pp.55-60
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• 2002

본 연구는 $580^{\circ}C$의 저온에서 ICPHFCVD(inductively coupled plasma hot filament chemical vapor deposition)를 이용하여 탄소나노튜브를 수직성장 시키는 것을 나타낸 것이다. 또한, 탄소나노튜브의 끝단에 존재하는 Ni-tip을 비성질 탄소같은 탄소질 물질등의 서로 다른 에칭특성에 기초하여 RF plasma를 이용하여 일회 공정으로 불순물을 정제하고, 고찰하였다. 정제된 이후의 탄소나노튜브는 속이 비어있는 다중벽 탄소나노튜브로 나타났으며, 성장된 탄소나노튜브는 외경과 내경은 50 nm와 25 nm였다. 또한, 탄소나노튜브의 graphite 층의 총수는 약 82개 층으로 구성되었으며, 층과 층간의 거리는 0.34nm였다. 그리고 TEM 관찰 결과, 탄소나노튜브 tip의 Ni촉매는 계속적인 에칭 공정에 의해 효과적으로 제거 되었다.

• 한국수소및신에너지학회논문집
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• 제33권2호
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• pp.148-157
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• 2022

Research on hydrogen storage is active to properly deal with hydrogen, which is considered a next-generation energy medium. In particular, research on metal hydride with excellent safety and energy efficiency has attracted attention, and among them, magnesium-based hydrogen storage alloys have been studied for a long time due to their high storage density, low cost, and abundance. However, Mg-based alloys require high temperature conditions due to strong binding enthalpy, and have many difficulties due to slow hydrogenation kinetics and reduction in hydrogen storage capacity due to oxidation, and various strategies have been proposed for this. This research manufactured Mg₂Ni to improve hydrogenation kinetics and synthesize about 5, 10, 20 wt% of CaF₂ as a catalyst for controlling oxidation. Mg₂NiHx-CaF₂ produced by hydrogen induced mechanical alloying analyzed hydrogenation kinetics through an automatic PCT measurement system under conditions of 423 K, 523 K, and 623 K. In addition, material life cycle assessment was conducted through Gabi software and CML 2001 and Eco-Indicator 99' methodology, and the environmental impact characteristics of the manufacturing process of the composites were analyzed. In conclusion, it was found that the effects of resource depletion (ARD) and fossil fuels had a higher burden than other impact categories.

• 대한환경공학회지
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• 제28권4호
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• pp.368-375
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• 2006

순수한 아나타제 구조로 이루어진 DT51D $TiO_2$에 $CrO_x,\;FeO_x,\;MnO_x,\;LaO_x,\;CoO_x,\;NiO_x,\;CeO_x,\;CuO_x$와 같은 단일 산화물 촉매를 각각 5 wt.% 담지하여 모델반응으로 선택한 기상 TCE 제거반응을 수행하였으며, 이로부터 얻어진 결과를 바탕으로 $CrO_x/TiO_2$-based 복합 산화물 촉매상에서 TCE 산화반응을 연구함으로써 유해 중금속의 사용량을 최소화하기 위한 최적의 촉매 디자인 방법을 도출하고자 하였다. DT51D $TiO_2$에 담지된 여러 단일 금속 산화물들 중에서 기상 TCE 제거반응에 대하여 $CrO_x$가 가장 우수한 촉매활성을 보이는 것으로 나타났으며, 반응온도의 함수로 얻어진 TCE 제거반응의 활성은 $CrO_x$의 담지량에 의존하였다. 5 wt.% $CrO_x$-based 복합 산화물 촉매는 10 wt.% $CrO_x$만으로 이루어진 단일 산화물 촉매와 거의 동일한 수준의 TCE 제거반응 활성을 보였을 뿐만 아니라 이 복합 산화물 촉매들은 10 wt.% $CoO_x,\;MnO_x,\;FeO_x,\;NiO_x$ 등과 같은 단일 산화물 촉매들보다 높은 반응활성을 갖는 것으로 나타났다. 단일 산화물 촉매의 반응활성과 비교하였을 때 5 wt.% $CrO_x$-based 복합 산화물 촉매상에서 TCE 제거반응 동안에 얻어지는 반응활성의 증가 정도는 $420^{\circ}C$ 이하의 반응온도 기준으로 약 $10{\sim}80%$ 이상이었다. 따라서, CVOCs 제거반응을 위하여 널리 사용되고 있는 단일 $CrO_x/Al_2O_3$ 촉매보다는 $CrO_x$의 사용량을 최소화하면서도 우수한 반응활성을 얻을 수 있는 $CrO_x/TiO_2$-based복합 산화물 촉매가 보다 바람직하며 하나의 대안적인 촉매 디자인 방법으로 응용될 수 있을 것으로 생각된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.53-56
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• 2007

미량의 Ru을 증진제로 첨가하여 니켈 촉매의 반응 활성을 증진시킴으로써, 저온 환원성과 장시간 반응에 대한 안정성을 확보하고자 하였다. Ni의 담지량은 12 wt%로 고정하였으며 이에 Ru을 각각 0.1, 0.3, 0.5 wt%로 변화시켜 2차 담지하였다. 메탄의 수증기/이산화탄소 복합 개질 반응에 있어 니켈 촉매에 Ru을 2차 담지 한 촉매는 800 $^{\circ}C$, GHSV(gas hourly space velocity) 265,000 $h^{-1}$ 하에서 100 %에 가까운 $CH_{4}$ 전환율을 보였으며, GHSV 1,060,000 $h^{-1}$ 일 때에도 10시간 동안 90 %의 $CH_{4}$ 전환율을 기록하였다. 또한 이 중 0.3 wt%의 Ru를 담지한 경우가 1,060,000 $h^{-1}$의 조건하에서도 95 %이상으로 가장 높은 $CH_{4}$ 전환율로 유지되었다. $H_{2}-TPR$ 분석 결과, Ni(12)/$MgAl_{2}O_{4}$ 와 비교해 볼 때 Ru(0.5)/Ni(12)/$MgAl_{2}O_{4}$와 Ru(0.3)/Ni(12)/$MgAl_{2}O_{4}$ 촉매의 경우 150 $^{\circ}C$에서 저온 환원이 가능한 $RuO_{2}$의 존재를 확인할 수 있었다.

• 공업화학
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• 제21권1호
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• pp.63-70
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• 2010

석유화학공업에서 발생한 2종류의 금속산화물계열 폐 촉매(Ni-Mo, Co-Mo)를 휘발성유기화합물(VOCs) 제거를 위한 촉매 연소 공정에 재이용하였다. 특히 폐 촉매의 재생방법에 따른 VOCs 제거효과를 검토하여 최적의 재생 조건을 살펴보았다. 폐 촉매는 1) 산 수용액, 2) 알칼리 수용액, 3) 세정액 및 4) 스팀(steam) 등을 이용하여 재생 처리하였고, 재생 처리 전-후의 이들 촉매의 물리화학적 특성 변화는 질소흡착등온선, X-선 회절분석기(XRD) 및 에너지분산 X-선 분광기(EDS)를 갖춘 주사현미경(SEM)으로 조사하였다. Benzene 산화반응 실험 결과 폐 촉매는 VOCs 연소 촉매로 재이용 가능성이 높았다. 그리고 이들 폐 촉매의 활성은 전처리 조건에 따라 다르게 나타났으나, 두 폐 촉매 모두 0.1 N $C_2H_2O_4$ 용액으로 처리할 때 활성이 가장 좋았다. 또한 최적 조건(0.1 N $C_2H_2O_4$)에서 처리한 촉매는 다른 방향족 화합물(Toluene/Xylene) 처리에도 충분히 적용할 수 있었다.

• 한국수소및신에너지학회논문집
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• 제23권4호
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• pp.346-352
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• 2012

The properties of methane oxidation were studied in this research over transition metal containing $CeO_2$ (TM/$CeO_2$, TM=Ni, Co, Cu, Fe) with TM content of 5 wt. % at atmospheric pressure. The characteristics of catalysts were investigated by various characterization techniques, including XRD, GC, SEM and EPMA analyses. The catalytic tests were carried out in a fixed Rmix ratio of 1.5 ($CH_4/O_2$) in a fixed-bed reactor operating isothermally at atmospheric pressure. Only the Ni/$CeO_2$ catalysts showed syngas production above $400^{\circ}C$ via typical partial oxidation reaction whereas other catalysts induced complete oxidation resulting in the production of $CO_2$ and $H_2O$ in whole reaction temperature range. From the quantitative analysis on carbon deposition after catalytic tests, Cu/$CeO_2$ was found to show the highest resistance on carbon deposition. Therefore Cu can be proposed as an efficient catalyst element which can be combined with a conventional Ni-based SOFC anode to enhance the carbon tolerance.

• 한국수소및신에너지학회논문집
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• 제25권4호
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• pp.378-385
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• 2014

In this research, we investigate electrical performance and electrochemical properties of graphene supported Pt (Pt/G) and PtM (M = Ni and Y) alloy catalysts (PtM/Gs) that are synthesized by modified polyol method. With the PtM/Gs that are adopted for oxygen reduction reaction (ORR) as cathode of proton exchange membrane fuel cells (PEMFCs), their catalytic activity and ORR performance and electrical performance are estimated and compared with one another. Their particle size, particle distribution and electrochemically active surface (EAS) area are measured by TEM and cyclic voltammetry (CV), respectively. On the other hand, regarding ORR activity and electrical performance of the catalysts, (i) linear sweeping voltammetry by rotating disk electrode and rotating ring-disk electrode and (ii) PEMFC single cell tests are used. The TEM and CV measurements demonstrate particle size and EAS of PtM/Gs are compatible with those of Pt/G. In case of PtNi/G, its half-wave potential, kinetic current density, transferred electron number per oxygen molecule and $H_2O_2$ production % are excellent. Based on data obtained by half-cell test, when PEMFC singlecell tests are carried out, current density measured at 0.6V and maximum power density of the PEMFC single cell employing PtNi/G are better than those employing Pt/G. Conclusively, PtNi/Gs synthesized by modified polyol shows better ORR catalytic activity and PEMFC performance than other catalysts.

• 한국분말재료학회지
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• 제17권6호
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• pp.489-493
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• 2010

Nickel-based and iron-based alloys have been developed and commercialized for a wide range of high performance applications at severely corrosive and high temperature environment. This alloy foam has an outstanding performance which is predestinated for diesel particulate filters, heat exchangers, and catalyst support, noise absorbers, battery, fuel cell, and flame distributers in burners in chemical and automotive industry. Production of alloy foam starts from high-tech coating technology and heat treatment of transient liquid-phase sintering in the high temperature. These technology allow for preparation of a wide variety of foam compositions such as Ni, Cr, Al, Fe on various pore size of pure nickel foam or iron foam in order for tailoring material properties to a specific application.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2008년도 춘계학술 발표회
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• pp.123-126
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• 2008