• Korean Journal of Crystallography
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• v.12 no.1
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• pp.20-24
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• 2001

NiZn-ferrite was synthesized usign waste iron oxide catalysts which were produced from styrene monomer process and buried underground as an industrial wastes. The spinel type ferrite was obtained by calcination and sintering of the mixture of finely ground waste catalysts, nickel oxide and zinc oxide powders. The sintered body of Ni/sub 0.5/Zn/sub 0.5/Fe₂O₄ composition at 1230℃ for 5 hours showed the density of 5.38g/㎤, and initial permeability of 59 at 1 kHz. Not only cerium oxide, which existed as a major component in the catalyst, but also unicorporated NiO and ZnO into spinel structure remained as second phases after sintering.

• Carbon letters
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• v.14 no.4
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• pp.243-246
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• 2013

In this work, electroless Ni-plating on polyethylene terephthalate (PET) ultra-fine fibers surfaces was carried out to improve the electric conductivity of the fiber. The surface properties of PET ultra-fine fibers were characterized using scanning electron microscopy, X-ray diffraction, and contact angle analyses. The electric conductivity of the fibers was measured using a 4-point testing method. The experimental results revealed the presence of island-like nickel clusters on the PET ultra-fine fibers surfaces in the initial plating state, and the electric conductivity of the Ni-plated fibers was enhanced with increasing plating time and thickness of the Ni-layers on the PET ultra-fine fibers.

• 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.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.147-152
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• 2002

This paper was studied on corrosion of heat exchanger tube for absorption refrigeration machine. In the 62 % lithium bromide solution at $60^{\circ}C$, polarization test of Cu, Al-brass, 10 % cupro nickel(90-10 % Cu-Ni) and 30 % cupronickel(70-30 % Cu-Ni) tube was carried out. And polarization behavior, polarization resistance characteristics, open circuit potential, anodic polarization of heat exchanger tube for absorption refrigeration machine were considered. The main results are as following: The open circuit potential of Al-brass tube becomes less noble than that of Cu tube, corrosion current density of that becomes lower than Cu tube. The open circuit potential of cupronickel tube is more noble than that of Cu tube, corrosion current density of that is controlled than Cu tube. The passivation critical current of 30 % Cu-Ni tube is lower than that of 10 % Cu-Ni tube, potential of passive region of that is more wide than 10 % Cu-Ni tube.

• Journal of Welding and Joining
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• v.13 no.3
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• pp.34-45
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• 1995

9%Ni강은 1944년 미국의 INCO(International Nickel Co., Ltd.)에 의해 최초 로 개발된 강도가 높고 용접성이 우수한 강제로서, 특히 극저온에서의 충격 인성이 우수하고 경제적으로도 유리하여 LNG 탱크 소재로서 사용한 실적이 많으며, 그동안 일본이 주축이 되어 강재의 품질개선 및 고능률.고품질의 용접기술 개발 등을 비롯 하여 탱크의 대형화 추세에 따른 안전성 확보를 위한 연구도 계속되고 있다. 이러한 추세에 동참하여 우리나라도 1993년 국산의 9%Ni강을 성공적으로 개발하게 되었고, 그 품질특성에 대해서도 국내외에 발표되었으나 여건이 미비하여 현재 국내에서 건설 중인 탱크의 소재로서는 공급되지 못하였다. 그러나 최근에 개발된 국산 강제는 자체 시험결과 뿐 아니라 외국 유수 연구기관의 시험결과에서도 각종 품질특성이 선진 제품 과 동등 이상으로 우수함이 입증되어, 가까운 장래 건설예정인 국내공사에는 물론 해외에서도 사용될 것으로 기대되고 있다. 따라서 본 해설은 향후 국내외의 LNG 수요 를 고려할 때 대형 저장탱크의 건설이 활발해 질 것으로 전망됨에 따라 9%Ni강의 현황 과 함께 최근 개발된 국산 강재의 용접특성에 대하여 소개하고자 한다.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.56-60
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• 2003

폐 적층세라믹콘덴서(MLCC)로부터 Ni을 회수하기 위하여 침출실험을 수행하였다. 침출용매로 $HNO_3,\;HCl\;H_2SO_4$을 사용하여 시간의 변화, 반응온도의 변화, 시료 입도와 광액농도의 변화가 Ni의 침출율에 미치는 영향과 최적 침출 조건을 조사하였다. 그 결과 HCl, $H_2SO_4$을 침출용매로 사용했을 때 Ni 침출의 최적 조건은 산농도 5M, 반응온도 $90^{\circ}C$나타났으며, $HNO_3$을 침출용매로 사용했을 때 최적 침출 조건 산농도 1M, 반응온도 $70^{\circ}C$에서 광액농도 500ml당 20g일때 Ni 침출율이 98%로 최대였다.

• Journal of Surface Science and Engineering
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• v.24 no.4
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• pp.206-214
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• 1991

In the basic study of selective electroless Ni plating of Si wafers, plating rate and physical properties are investigated to obtain optimum conditions of contact hole filling. Si wafers are excellently activated in the concentration of 0.5M IF, 1mM PdCl2, 2mM EDTA at $70^{\circ}C$, 90sec. The optimum condition of Ni-B deposition on p-type Si wafers is 0.1M NiSO4, 0.11M Citrate, $70^{\circ}C$, pH6.8, 8mM DMAB. The main factor in the sheet resistences variation of films is amorphous and on heat treating matrix was transformed into a stable phase (Ni+Ni3B) at $300-400^{\circ}C$. But pH or DMAB concentration in the plating solution doesn't play role of heat-affected phase change.

• Journal of Surface Science and Engineering
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• v.43 no.1
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• pp.31-35
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• 2010

Coatings of Ni-17 at.%W were electroplated on a steel substrate, and their corrosion behavior was investigated between 600 and $800^{\circ}C$ in an Ar-0.2%$SO_2$ atmosphere. They delayed the corrosion of the steel substrate. They were corroded into an outer NiO-rich layer, and an inner ($WO_3+NiO+NiWO_4$)-mixed oxide layer. Below these oxide layers, a sulfide layer gradually formed.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.113-116
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• 2011

Slope analysis method was applied to determine the stoichiometry of the solvent extraction reaction of Ni(II) by Alamine336 from strong HCl solution range from 1 to 10 M. Solvent extraction data was obtained from the literature. The effective equilibrium constant for the solvent extraction reaction was estimated by considering the ionic equilibria of $NiCl_2$ in the HCl solution. The measured distribution coefficients of Ni(II) agreed well with those calculated in this study. Our results suggest that further study on the measurement of the activities of nickel complexes at high HCl solution need to be done.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.4
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• pp.280-285
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• 2003

The influence of silicon surface damage on nickel-silicide (NiSi) has been characterized and H$_2$ anneal and TiN rapping has been applied to suppress the electrical, morphological deterioration phenomenon incurred by the surface damage. The substrate surface is intentionally damaged using Ar IBE (Ion beam etching) which can Precisely control the etch depth. The sheet resistance of NiSi increased about 18% by the surface damage, which is proven to be mainly due to the reduced silicide thickness. It is shown that simultaneous application of H: anneal and TiN capping layer is highly effective in suppressing the surface damage effect.