• Bulletin of the Korean Chemical Society
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• v.24 no.7
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• pp.906-910
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• 2003

Hydrothermal reactions of Ni(NO₃)₂· 6H₂O with trans-1,2-bis(4-pyridyl)ethylene (bipyen), in the presence of a linear 2,6-naphthalene dicarboxylic acid (NDCH₂) and a bent 4,4'-oxybis(benzoic acid) (OBCH₂), gave a 2-D coordination polymer [Ni(NDC)(bipyen)(H₂O)] (1) and also a 2-D coordination polymer [Ni(OBC)(bipyen)]· H₂O (2), respectively. A reversible de-coordination and re-coordination of an aqua ligand was observed for polymer 1. Polymer 2 has an undulated 2-D network based on 50-membered rectangular grids, each of which has the dimension of 13.61 × 13.17 Å.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.627-628
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• 2006

The present work is a study on the argon gas pressure effects of Sinter/HIP sintering on microstructure and strength of different grades of TiC-NiMo cermets. Titanium carbide in the composition of different grades of TiC-NiMo cermets was ranged from 40 to 80 wt.% and the ratio of nickel to molybdenum in the initial powder composition was 1:1, 2:1 and 4:1 respectively. On the sintered alloys, the main strength characteristic, transverse rupture strength (TRS) was measured. Furthermore, the microstructure parameters of some alloys were measured and the pressure effect on pore elimination was evaluated. All the results were compared with common, vacuum sintered alloys. The TRS values of TiC-NiMo cermets could be considerably improved by using Sinter/HIP technique, for high-carbide fraction alloys and for alloys sintered at elevated temperatures.

• Bulletin of the Korean Chemical Society
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• v.11 no.5
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• pp.379-383
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• 1990

$YBa_2Cu_{3-x}Ni_xO_{7-{\delta}}$, with x = 0.05, 0.2, 0.4, 0.7 and 1.0 had been prepared by the thermal decomposition of corresponding nitrates. Among them, the sample with x = 0.05 shows above-liquid-$N_2$ temperature superconductivity with $T_c$ of 88.7K. According to the X-ray diffraction analysis, its crystal symmetry was estimated as orthorhombic with the lattice parameters of a = 3.866${\AA}$, b = 3.893${\AA}$, c = 11.715${\AA}$. The chemical composition of the sample was determined by electron probe microanalysis and the chemical composition around its grain boundaries was carefully studied by the X-ray line scanning technique. From the observed binding energy of Ni-$2p_{3/2}$ orbital electron (B.E. = 853 eV) measured by X-ray photoelectron spectroscopy, the valency state of nickel stabilized in $YBa_2Cu_{2.95}Ni_{0.05}O_{7-{\delta}}$ oxide lattice could be determined to be Ni(II).

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1093-1097
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• 1994

The interaction of oxygen molecule with Ni44(111) model surface to which the molecule approaches is studied by calculating the relevant DOS and COOP with the tight-binding EHT method. It is found that the dissociative adsorption of oxygen takes place as a result of electron transfer from the Ni d${\pi}$ orbital to the antibonding 1${\pi}_g$ orbital of the oxygen molecule. This finding is noteworthy to contrast with the case of Ni(100) surface in which the electron transfer takes place from the Ni d${\delta}$ orbital of the nickel surface.

• Current Applied Physics
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• v.18 no.12
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• pp.1583-1591
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• 2018

We analysed perovskite $CH_3NH_3PbI_{3-x}Cl_x$ inverted planer structure solar cell with nickel oxide (NiO) and spiroMeOTAD as hole conductors. This structure is free from electron transport layer. The thickness is optimized for NiO and spiro-MeOTAD hole conducting materials and the devices do not exhibit any significant variation for both hole transport materials. The back metal contact work function is varied for NiO hole conductor and observed that Ni and Co metals may be suitable back contacts for efficient carrier dynamics. The solar photovoltaic response showed a linear decrease in efficiency with increasing temperature. The electron affinity and band gap of transparent conducting oxide and NiO layers are varied to understand their impact on conduction and valence band offsets. A range of suitable band gap and electron affinity values are found essential for efficient device performance.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.189-198
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• 2011

In the present paper two new thiosemicarbazones i.e., 4[N-(4'-ethylbenzalidene)amino]antipyrine thiosemicarbazone (EBAAPTS) and 4[N-(2',4'-dimethylbenzalidene)amino]antipyrine thiosemicarbazone (DMBAAPTS) have been synthesized and characterized. The complexing abilities of these thiosemicarbazones i.e. EBAAPTS and DMBAAPTS towards cobalt(II) and nickel(II) salts have been explored. The reactions of the hot ethanolic solutions of cobalt(II) and nickel(II) salts with EBAAPTS and DMBAAPTS led to the formation of the novel complexes of general composition [$MX_2(L)H_2O$] (M=$Co^{2+}$ or $Ni^{2+}$; X=$Cl^-$, $Br^-$, $NO_3^-$, $NCS^-$ or $CH_3COO^-$; L=EBAAPTS or DMBAAPTS). The newly synthesized complexes have been characterized by elemental analyses, molar mass, molar conductance, magnetic susceptibility, infrared and electronic spectral studies. The molar conductance measurements of the complexes in nitrobenzene correspond to their non-electrolytic nature. All the complexes are of high-spin type. On the basis of spectral studies an octahedral geometry has been assigned for Co(II) and Ni(II) complexes of the type [$MX_2(L)H_2O$]. These complexes were screened for their antibacterial and antifungal activities on different species of pathogens, fungi and bacteria and their biopotency has been discussed.

• Journal of Sensor Science and Technology
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• v.14 no.1
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• pp.52-55
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• 2005

Ni oxide thin films with thermal sensitivity superior to Pt and Ni thin films were formed through annealing treatment after Ni thin films were deposited by a r.f. magnetron sputtering method. Resistivity values of Ni oxide thin films were in the range of $10.5{\mu}{\Omega}cm$ to $2.84{\times}10^{4}{\mu}{\Omega}cm$ according to the degree of Ni oxidation. Also temperature coefficient of resistance(TCR) values of Ni oxide thin films depended on the degree of Ni oxidation from 2,188 ppm/$^{\circ}C$ to 5,630 ppm/$^{\circ}C$ in the temperature range of $0{\sim}150^{\circ}C$. Because of the high linear TCR and resistivity characteristics, Ni oxide thin films exhibit much higher sensitivity to flow and temperature changes than pure Ni thin films and Pt thin films.

• Journal of Electrochemical Science and Technology
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• v.9 no.2
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• pp.93-98
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• 2018

$MnO_2$, a metal oxide used as an electrode material in electrochemical capacitors (EDLCs), has been applied in binary oxide and conducting polymer hybrid electrodes to increase their stability and capacitance. We developed a method for electrodepositing Mn-Ni oxide/PANI, Mn-Ni oxide/PEDOT, and Mn-Ni-Ru oxide/PEDOT films on carbon paper in a single step using a mixed bath. Mn-Ni oxide/PEDOT and Mn-Ni-Ru oxide/PEDOT electrodes used in an electro-osmotic pump (EOP) have shown better efficiency compared to Mn-Ni oxide and Mn-Ni oxide/PANI electrodes through testing in water as a pumping solution. EOP using a Mn-Ni-Ru oxide/PEDOT electrode was also tested in a 0.5 mM $Li_2SO_4$ solution as a pumping solution to confirm the effect of the $Li^+$ insertion/de-insertion reaction of Ruthenium oxide on the EOP. Experimental results show that the flow rate increases with the increase in current in a 0.5 mM $Li_2SO_4$ solution compared to that obtained when water was used as a pumping solution.

• Journal of Surface Science and Engineering
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• v.40 no.1
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• pp.32-38
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• 2007

Ni coating layers were formed using a newly developed electroless Ni plating solution. The properties of Ni coating layer such as internal stress, hardness, surface roughness, crystallinity, solderability and surface morphology were investigated using various tools. Results revealed that internal stress decreased with plating time and reached $40N/mm^2$ at 20 minutes of the plating time. Hardness increased with increasing P content and thickness. Surface roughness of the pad decreased with Ni and Ni/Au plating. Crystallinity decreased with increasing P content. Solderability based on wettability decreased with Ni and Ni/Au plating. Based on surface morphology, it is expected that Ni coating layer formed using a newly developed electroless Ni plating solution is lower than that formed using a commercial electroless Ni plating solution in possibility of black pad occurrence.

• Journal of Hydrogen and New Energy
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• v.22 no.6
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• pp.787-793
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• 2011

A 76.5wt%Mg - 23.5wt%Ni (Mg-23.5Ni) sample was prepared by reactive mechanical grinding (RMG) and its hydriding and dehydriding properties were then investigated. Activation of the Mg-23.5Ni sample was completed only after two hydriding (under 12 bar $H_2$) - dehydriding (under 1.0 bar $H_2$) cycles at 593K. The reactive mechanical grinding of Mg with Ni is considered to facilitate nucleation and shorten diffusion distances of hydrogen atoms. After hydriding - dehydriding cycling, the Mg-23.5Ni sample contained Mg2Ni phase.