• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3749-3754
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• 2010

Various terphenyl and quaterphenyl derivatives were prepared by the Ni-NHC catalyzed cross coupling of the corresponding biphenyl- and terphenyl-sulfonates with arylmagnesium bromides. The reactions proceeded rapidly via a nucleophilic aromatic substitution of the alkoxysulfonyl moieties by the aryl nucleophiles to afford high yields within just 1.5 h at room temperature in spite of the low reactivity of the sulfur electrophiles.

• Advances in Energy Research
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• v.3 no.1
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• pp.45-57
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• 2015

This article is addressed to define a new composite electrode constituted by porous nickel and an array of highly ordered $TiO_2$ nanotubes obtained by a previous galvanostatic anodization treatment in an ethylene glycol solution. The electrochemical performances of the composite anode were evaluated in a photo-electrolyser, which showed good solar conversion efficiency with respect to the UV irradiance together with a reduction of energy consumption. Such a combination of materials makes our system simple and able to work both in dark and under solar light exposure, thus opening new perspectives for industrial-scale applications.

• Journal of Surface Science and Engineering
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• v.31 no.4
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• pp.209-216
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• 1998

It is well knownthat electroledd plating is the desirable surface treatment method which is being widely used to all kinds of material such as requiring corrosing resistance, wear resistance and conductivity, especially nonconductivity materials' surface plating. However, it is suggested that there are some problems that must be solved, for exaple, rate of plating, corrosion resistance, thickness of plating film etc. Therefore in this paper, when electroless nickel plating was performed on the PZT(Pb(Zr,Ti))with varying of solution composition such as NaOH, and $H_2NCH_2COOH$, the effect of the rate of plating and corrosion resistance were investigated.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.151-152
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• 2011

본 연구에서는 황산니켈, 아세트산니켈, 썰파민산니켈 등 니켈 염 종류에 따른 무전해 니켈 도금피막의 기계적 특성을 평가하고자 하였다. 동일한 두께로 도금피막을 형성하여 내절성 시험결과 황산니켈을 사용한 무전해 니켈 도금피막의 경우 97회, 아세트산니켈을 사용한 경우 259회, 썰파민산 니켈을 사용한 경우 467회의 굴곡 시험 후 도금 피막이 파괴되어 썰파민산니켈이 니켈염으로 사용될 경우 가장 우수한 피막을 나타내었다. 도금피막의 연신울 측정결과 니켈염으로 황산니켈을 사용할 경우 0.28%의 연신율을 나타내었고 아세트산니켈을 사용할 경우 0.32%의 연신율을 나타내었고 썰파민산니켈을 니켈염으로 사용한 결과 0.69%의 높은 연신율을 나타내었으며 개발한 도금액을 PCB 도금을 위한 Cu Pattern에 도금한 경우 Cu line에 선택적으로 도금이 가능하였다.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.1
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• pp.47-58
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• 2004

Loss factors of A356, Mn-Cu alloy and aluminum matrix composites reinforced with $SiC_p$ and Ni-coated graphite particles at various contents have been investigated using clamped-free cantilever beam method. The loss factors of half-power bandwidth of the specimens were measured over a wide range of frequencies from 50 to 3300Hz. Among the specimens, Al-10%$SiC_p$-10%$C_p$ showed the highest loss factor at the mode I, while Mn-Cu alloy showed the highest loss factors at the modes II and III. Consequently, at the mode I the Al-10%$SiC_p$--10%$C_p$ showed the loss factor of 0.00093, which is 2.64 and 1.58 times higher than those of A356 and Mn-Cu alloy, respectively.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.431-434
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• 2008

Effects of microstructure on the toughness of low carbon HSLA steels were investigated. Nickel decreased the ferrite-austenite transformation temperature, resulted in increase of the fraction of bainitic ferrite. However, it was decreased with increasing deformation amount at austenite region. Since fine austenite grains formed by dynamic recrystallization under large strain transformed to acicular ferrite or granular bainite rather than bainitic ferrite. The effective grain size, thus, was decreased by deformation and it resulted in lower ductile-brittle transition temperature (DBTT). The bainitic ferrite was thought to inhibit the fracture crack initiation and to delay the crack propagation by its high dislocation density and hard interlath $2^{nd}$ phase constituents, respectively. Thus, DBTT was also decreased by Ni addition in low carbon HSLA steels.

• Transactions of Materials Processing
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• v.29 no.6
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• pp.307-315
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• 2020

The cemented carbide and stainless steel were bonded using a hot-vacuum brazing method to analyze the bonding interface. Since it is suitable for the hot vacuum brazing, nickel metal was used as a binder among the main components of the cemented carbide, and a new cemented carbide material was developed by adjusting the alloy composition. The paste, which is one of the important factors affecting the hot vacuum brazing bonding, was able to improve brazing adhesion by mixing solder as Ni powder and a binder as an organic compound at an appropriate ratio. Division of the stainless steel yielded a dense brazing result. This study elucidated the interfacial characteristics of wear-resistant parts by bonding stainless steel and cemented carbide via hot vacuum brazing.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.595-595
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• 2003

I. Objectives This study was done to evaluate which type of Ni-Ti instrument be able to perform canal shape well in the simulated canal with abrupt curvature near it's apex. II. Materials and Methods A total of 96 simulated root canals were made in epoxy resin(EPOXICURETM, BUEHLER, USA), ＃15 finger spreader (MANI, Japan) were used as root canal templates. The simulated root canal were made with radius of curvature of 1.5 mm, 3.0 mm, 4.0 mm, 6.0 mm respectively, and angle of curvature of all simulate camals was 90 degree.(omitted)

• Journal of Technologic Dentistry
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• v.8 no.1
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• pp.45-50
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• 1986

This study investigated the effect of burnout temperature on the castability of some nickelchromium alloys for porcelain fused to metal system and the effect of beryllium on the castability. Four alloys were evaluated: two contained beryllium(rexillium III, Super I) and two nonberyllium(Unibond, NNB). five burnout temperature, ranging form 100$^{\circ}F$ to 1800$^{\circ}F$, were aet at 200$^{\circ}F$ intervals for this study. The results obtained were as follows: 1. Beryllium-containing alloys were more castable than nonberyllium-containing alloys. 2. There was an optimal burnout temperature of range from 1400$^{\circ}F$ to 1600$^{\circ}F$ for the berylliumcontaining alloys studied. 3. An optimal burnout temperature for the nonberyllium alloys was not established.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.170-170
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• 1999

No Abstract, See Full Text