• Proceedings of the Korean Magnestics Society Conference
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• 2000.05a
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• pp.98-99
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• 2000

• Proceedings of the Korean Magnestics Society Conference
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• 1995.05a
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• pp.86-87
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• 1995

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.10a
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• pp.65-66
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• 2003

• Proceedings of the Korean Magnestics Society Conference
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• 1998.05a
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• pp.52-53
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• 1998

• Journal of the Korean Magnetics Society
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• v.11 no.5
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• pp.196-201
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• 2001

The dependence of CoFe interfacial layer thickness and plasma oxidation condition on tunneling magnetoresistance (TMR) in Ta/NiFe/FeMn/NiFe/Al$_2$O$_3$/NiFe/Ta tunnel junctions was investigated. As the CoFe layer thickness increases, TMR ratio rapidly increases to 13.7 % and decreases with further increase of the CoFe layer thickness. The increase of TMR with the CoFe thickness up to 25 was thought to be due mails to the high spin-polarization of CoFe. The maximum MR of 15.3% was obtained in the Si(100)/Ta(50 )/NiFe(60 )/FeMn(250 )/NiFe(70 )/Al$_2$O$_3$/NiFe(150 )/Ta(50 ) magnetic tunnel junction with a 16 Al oxidized for 40 sec using a Ar/O$_2$ (1:4) mixture gas.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.233-243
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• 2009

We have investigated the infrared spectra for CO adsorbed on silica supported nickel(Ni-Si$O_2$), silica supported copper(Cu-Si$O_2$), silica supported nickel-copper alloys(Ni/Cu-Si$O_2$) of several compositions with varying CO pressures(0.2 $torr{\sim}$50 torr) at room temperature and on pumping to vacumn at room temperature within the frequency range of 1500 $cm^{-1}{\sim}2500\;cm^{-1}$. Four bands(2059.6 $cm^{-1},\;{\sim}$2036.5 $cm^{-1},\;{\sim}$ 1868.7 $cm^{-1},\;{\sim}$ 1697.1 $cm^{-1}$) were observed for Ni-Si$O_2$, two bands($\sim$2115.5 $cm^{-1},\;{\sim}$1743.0 $cm^{-1}$) were observed for Cu-Si$O_2$ and five bands(${\sim}2123.2\;cm^{-1}$, 2059.6 $cm^{-1},\;{\sim}$2036.4 $cm^{-1},\;{\sim}$1899.5 $cm^{-1},\;{\sim}$1697.1 $cm^{-1}$) were observed for Ni/Cu-Si$O_2$. These absorption bands correspond with those of the previous reports approximately. The bands below 1800 $cm^{-1}$ were only observed with Ni metal or Ni/Cu alloy crystal plane containing step at room temperature and the ${\sim}1697.1\;cm^{-1}$ bands observed with Ni-Si$O_2$ and Ni/Cu-Si$O_2$ may be ascribed to CO molecule adsorbed on the adsorption sites near step. The bands below 2000 $cm^{-1}$ were rarely observed with Cu metal crystal plane at room temperature and the 1743.0 $cm^{-1}$ bands may be ascribed to CO molecule adsorbed on the adsorption sites near step. The band shifts of adsorbed CO with varing Cu contents from 0 to 0.5 mole fraction at the same CO pressure or at the same pumping time to vacumn were below 21 $cm^{-1}$. and comparatively small than those with other ⅠB metal addition. It may means ligand effect of Cu d electron is small.

• Journal of the Korean Magnetics Society
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• v.7 no.3
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• pp.152-158
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• 1997

NiFeCo/ Cu /Co trilayers were formed on 4$^{\circ}$ tilt-cut Si(111) substrates with a Cu(50$\AA$) underlayer and large-scaled test magnetoresistive RAM (MRAM) cells were fabricated using a conventional lithographic process. NiFeCo / Cu /Co trilayers deposited on the same templates without any applied magnetic field showed strong in plane uniaxial magnetic anisotropy and excellent magnetoresistive (MR) properties such as high MR ration and sensitivity within a low external magnetic field, which are suitable properties for a MRAM application. In order to obtain optimized MR results in NiFeCo /Cu /Co trilayers, the thickness of Cu spacer was varied. Interlayer coupling between two magnetic layers was observed and it was found that the MR properties were strongly dependent on the coupling force, especially near 20 $\AA$ of Cu spacer thickness. Test MRAM cells were fabricated using the optimized NiFeCo (60$\AA$)/ Cu (25$\AA$)/ Co (30$\AA$) trilayer thin films. With a 10 mA of sense current and 5$\times$$10^5$ of word current, 10 mV of signal output was obtained, which implies the strong potentials of NiFeCo/ Cu /Co trilayer thin films for a MRAM application.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.3
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• pp.110-114
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• 2017

$NiO/NiCo_2O_4$ nanocubes were successfully synthesized via the calcination process of $Ni_3[Co(CN)_6]_2$ PBAs. The prepared monodispersed $Ni_3[Co(CN)_6]_2$ PBAs were aggregated by 'self-assembly' of the nuclei generated during the synthesis reaction. The self-assembly rate of the particles is affected by the temperature and the amount of surfactant SDBS (sodium dodecylbenzenesulfonate). FESEM analysis shows that monodispersed 200 nm PBA nanocubes are obtained at 0.25 g SDBS and $60^{\circ}C$ temperature. Thermal behavior was confirmed by thermogravimetric-differential thermal analysis (TG-DTA) to determine optimal calcination conditions. Then, field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analyzes were performed to investigate the morphology and crystallinity of the particles precursors and $NiO/NiCo_2O_4$ nanocubes.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.2
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• pp.89-98
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• 1988

Three experiments were conducted to determine whether cobalt (Co) or nickel (Ni) could prevent zinc (Zn) deficiency signs in pigs fed a high calcium (Ca) corn-soybean diet. The basal diet contained 1.3% Ca, .93% phytic acid and means of 34 to 48 ppm Zn. After weanling, pigs in experiment I were fed the basal diet for 9 weeks, and was found that 50 ppm Co or Ni for 5 weeks increased average daily weight gain (ADG) and reversed skin lesions toward normal. These effects were similar to those of 100 ppm supplemental Zn. The Zn content and alkaline phosphatase activity of serum from pigs supplemented with Co or Ni were higher at 2 weeks and 4 weeks (P<.05) than those of the basal group. Zn content of bone, liver and kidney, and alkaline phosphatase activity in bone were increase after 5 weeks of supplementation with Co or Ni. In experiments 2 and 3, addition of 54 ppm and 27 ppm of either Co or Ni increased (P<.05) ADG and decreased incidence of skin lesions except in one group supplemented with 27 ppm Ni. Supplemental Co or Ni increased Zn in serum and alkaline phosphatase activity in serum and bone in both experiments. Over all experiments, supplemental Co or Ni decreased Zn deficiency signs in the following order of effectiveness: 54 ppm Co, 54 ppm Ni, 27 ppm Co and 27 ppm Ni. The alleviation of signs of Zn deficiency by Co or Ni may have been the result of increased availability of dietary Zn.

• Journal of the Korean institute of surface engineering
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• v.56 no.5
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• pp.299-308
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• 2023

In this study, phosphorus (P)-doped nickel cobaltite (P-NiCo₂O₄) and nickel-cobalt layered double hydroxide (P-NiCo-LDH) were synthesized on nickel (Ni) foam as a conductive support using hydrothermal synthesis. The thermal properties, crystal structure, microscopic surface morphology, chemical distribution, electronic state of the constituent elements on the sample surface, and electrical properties of the synthesized P-NiCo₂O₄ and P-NiCo-LDH samples were analyzed using thermogravimetric analysis-differential scanning calorimetry (TGA-DSC), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The P-NiCo₂O₄ electrode exhibited a specific capacitance of 1,129 Fg^-1 at a current density of 1 Ag^-1, while the P-NiCo-LDH electrode displayed a specific capacitance of 1,012 Fg^-1 at a current density of 1 Ag-1. When assessing capacity changes for 3,000 cycles, the P-NiCo₂O₄ electrode exhibited a capacity retention rate of 54%, whereas the P-NiCo-LDH electrode showed a capacity retention rate of 57%.