• Title/Summary/Keyword: Nickel (Ni)

Search Result 1,524, Processing Time 0.028 seconds

Electrochemical Study of UBM Ni Prepared by Electroless Plating (무전해 도금법을 이용한 UBM 니켈 형성의 전기화학적 고찰)

  • Lee Jae Ho;Lee In Geon;Gang Tak;Kim Nam Seok;O Se Yong
    • Proceedings of the International Microelectronics And Packaging Society Conference
    • /
    • 2003.11a
    • /
    • pp.118-121
    • /
    • 2003
  • The electrochemical behaviors of UBM nickel were investigated. Electrode potential has been changed with the surface composition. Zinc is dissolved into the solution immediately after immersion. Electrode potential has three distinct regions: Zinc dissolution region, transient region and nickel plating region. The effects additives on electrode potential and polarization curves were also investigated. The addition of suppressor lowered the current density which is related with deposition rate.

  • PDF

Corrosion resistance and Hardness of Tin-Nickel Electrodeposits (주석-니켈합금 도금층의 내식성 및 경도)

  • 예길촌;채영욱
    • Journal of Surface Science and Engineering
    • /
    • v.32 no.4
    • /
    • pp.521-530
    • /
    • 1999
  • The corrosion resistance and the hardness of the tin-nickel alloy deposits electroplated in pyrophosphate bath were invesitigated according to electrolysis conditions and microstructure of the alloy. The weight loss of alloy deposits increased with the Sn content of single phase (Ni-Sn) alloy showing the lowest weight loss in the alloy with 54∼57wt% Sn. On the other hand, the multiphase alloy with 35∼42wt% Sn showed the highest one. The CASS test result was consistent with that of immersion test, and was good agreement with the corrosion data of polarization measurements. The hardness of alloy deposits decreased with the increase of Sn ratio in bath due to the grain size increase of the alloy. However, it increased noticeably with decreasing current density in the bath condition of low Sn ratio (0.1)

  • PDF

Hydrogen Induced Reduction of Fe- and Co-Oxides with Addition of Ni and Pd (철과 코발트 산화물의 수소 환원에 니켈 및 팔라듐 첨가의 효과)

  • Kim, Jong-Pal
    • Journal of Hydrogen and New Energy
    • /
    • v.22 no.1
    • /
    • pp.35-41
    • /
    • 2011
  • Temperature programmed reduction experiments for Fe- and Co-oxides were performed and weight losses were carefully measured to calculate the extent of reduction. Addition of nickel and palladium affected the reduction by lowering the DTG peak temperature. Reduction experiments for the oxides on alumina were also studied and the effect of nickel and palladium addition was confirmed. And that was explained by means of increased adsorption of hydrogen and increased diffusion ability of the surface hydrogen.

Nickel Catalyzed Silylation Reaction of Carbonyl Compounds with 1,1'-Bis(dimethylsilyl)ferrocene (니켈 촉매를 이용한 1,1'-Bis(dimethylsilyl)ferrocene과 Carbonyl 화합물의 Silylation 반응)

  • Gong, Yeong-Geon;Lee, Jeong-Hyeon
    • Journal of the Korean Chemical Society
    • /
    • v.46 no.2
    • /
    • pp.139-144
    • /
    • 2002
  • The nickel-catalyzed reation of 1,1'-bis(dimethysilyl)ferrocene[1] with carbonyls such as benzaldehyde, 4-cyaonbezaldehyde, trimethylacetaldehyde, acethon, and benzophenone afforded 3-oxa-2,5-disilacyclo-1,1'-ferrocene. In contrast, the reation of [1] with isobutyraldehyde under the same reation condition yielded the diinsertion products formed via the insertion of two aldehyde ligands into the Si-H bond of 1,1'-bis(dimethy)ferrocene.

Preparation and Characterization of Nickel(Ⅱ) and Copper(Ⅱ) Tetaaza Macrocyclic Complexes with Isonicotinate Ligands

  • Choi, Ki-Young;Kim, Moon-Jip;Kim, Dae-Sue;Kim, Yong-Son;Kim, Jae-Hyun;Ryu, Hai-Il;Lim, Youn-Mook;Kang, Seung-Gu;Shin, Ueon-Sang;Lee, Kyu-Chul;Hong, Choon-Pyo
    • Bulletin of the Korean Chemical Society
    • /
    • v.23 no.8
    • /
    • pp.1062-1066
    • /
    • 2002
  • The complexes [Ni(L)(INT)2]${\cdot}$5H2O (1) and [Cu(L)(H2O)](Cl)(INT)${\cdot}$3H2O (2) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18 ,07.12 ]docosane, INT = isonicotinate) have been prepared and characterized by X-ray crystallography, electronic absorption, and cyclic voltammetry. The crystal structure of 1 reveals an axially elongated octahedral geometry with two axial isonicotinate ligands. The electronic spectra, magnetic moment, and redox potentials of 1 also show a high-spin octahedral geometry. However, 2 shows that the coordination environment around the copper atom is a distorted square-pyramid with an axial water molecule. The spectra and electrochemical behaviors of 2 are also discussed.

Nickel Binding Protein (NBPI) and Its Gene from Streptomyces seoulensis

  • Kim, In-Kwon;Sa-Ouk kang
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 2001.06a
    • /
    • pp.52-52
    • /
    • 2001
  • Nickel-binding protein (NBP1) was purified from the crude extract of Streptomyces seoulensis using Ni$^{2+}$-charged metal chelate affinity chromatography. The molecular mass of NBPI determined on SDS-PAGE was 38kDa. An approximately 3 kb DNA fragment containing the structural gene for NBP1 was cloned from lEMBL3 genomic library of S. seoulensis using a DNA fragment PCR-amplified with the primers designed from N-terminal and internal amino acid sequences of NBP1.(omitted)

  • PDF

Fabrication and Properties of Alloy Foam Materials using Metal Powders (금속 분말을 이용한 합금폼 제조 및 특성)

  • Choi, James;Kim, Ku-Hwan
    • Journal of Powder Materials
    • /
    • v.17 no.6
    • /
    • pp.489-493
    • /
    • 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.

Carbon dioxide reforming of methane (CRM) that use nickel powder as catalyst

  • Kim, Dong-Wun;Kim, Kwang-Dae;Luo, Yuan;Seo, Hyun-Ook;Kim, Myoung-Joo;Kim, Young-Dok
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.02a
    • /
    • pp.347-347
    • /
    • 2010
  • We designed a new experimental set-up for measuring activity of heterogeneously catalyzed reactions. Using this set-up, we studied reduction of carbon dioxide by carbon dioxide reforming of methane (CRM) using nickel powder as catalyst. The properties of the catalysts were characterized by X-ray diffraction (XRD), Brunauer, Emmett & Teller (BET) surface area and X-ray photoelectron spectroscopy (XPS) techniques. The reactivity experiments were performed in the temperature range of $300\;-\;500^{\circ}C$. At reactivity experiment, result showed consumption of $CO_2$ and $CH_4$ with a 1:1 stoichiometry. At the same time, carbon monoxide and hydrogen were produced, which could be used for synthesizing fuels such as methanol. During the reaction, deposition of carbon on Ni was observed, which caused deactivation of the catalyst.

  • PDF