• Bulletin of the Korean Chemical Society
• /
• v.30 no.4
• /
• pp.846-848
• /
• 2009

Two modifications of the ${\alpha}\;and\;{\beta}$ forms of propyl mercaptan nickel(II) cluster, [$Ni_6(SCH_2CH_2CH_3)_{12}$], have been synthesized and their crystal structures have been determined by single-crystal X-ray diffraction. The alkyl groups are away from $Ni_6$ ring in $\alpha$ form whereas they are near to the Ni atom in $\beta$ form. The distance of Ni-H in $\beta$ form [2.576(5) $\AA$] is much shorter than that in $\alpha$ form [3.101(2) $\AA$]. In the crystal lattice of $\beta$ form, the whole structure forms a flower shape.

• Journal of the Korean Magnetics Society
• /
• v.5 no.5
• /
• pp.548-551
• /
• 1995

The effect of Cu substitution on the properties of NiZn ferrites sintered at low temperature with composition is investigated. The densification of NiCuZn ferrite in dependent upon Cu content in the composition of (N/sub 0.5-x/Cu/sub x/ Zn/sub 0.5/O)(Fe/sub 2/O/sub 3/)/sub 0.98/. Electrical resistivity is maximum at x=0.2. Dispersion characteristics of complex permeability of (Ni/sub 0.5-x/ Cu/sub x/Zn/sub 0.5/O)(Fe/sub 2/O/sub 3)/sub 0.98/ is observed above x=0.3 and relaxation frequency increases with higher temperature. The magnetic loss of NiCuZn ferrite is occurred above the Cu content x=0.3 at a low frequency.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.5
• /
• pp.840-842
• /
• 2007

• Journal of the Korean Chemical Society
• /
• v.67 no.3
• /
• pp.204-207
• /
• 2023

• Bulletin of the Korean Chemical Society
• /
• v.34 no.10
• /
• pp.2889-2894
• /
• 2013

A new complex [$Ni(phen)(C_9H_8Br_2NO_3)_2{\cdot}2CH_3OH{\cdot}2H_2O$] [phen: 1,10-phenanthroline $C_9H_8Br_2NO_3$: 3,5-dibromo-L-tyrosine] was synthesized and characterized by IR, elemental analysis and single crystal X-ray diffraction. X-ray crystallography shows that Ni(II) ion is six-coordinated. The Ni(II) ion coordinates with four nitrogen atoms and two oxygen atoms from three ligands, forming a mononuclear Ni(II) complex. The crystal crystallizes in the Orthorhombic system, space group $P2_12_12$ with a = 12.9546 ${\AA}$, b = 14.9822 ${\AA}$, c = 9.9705 ${\AA}$, V = 1935.2 ${\AA}$, Z = 1, F(000) = 1008, S = 0.969, ${\rho}_{calcd}=1.742g{\cdot}cm^{-3}$, ${\mu}=4.688mm^{-1}$, $R_1$ = 0.0529 and $wR_2$ = 0.0738 for 3424 observed reflections (I > $2{\sigma}(I)$). Theoretical study of the title complex was carried out by density functional theory (DFT) method and the B3LYP method employing the $6-3l+G^*$ basis set. The energy gap between HOMO and LUMO indicates that this complex is prone to interact with DNA. CCDC: 908041.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.12
• /
• pp.2196-2201
• /
• 2007

Materials used at microwave are usually used as a dielectric with a manufacturing purpose of printed circuit boards, etc. Complex permittivity of them can be measured from attenuation constant or propagation constant of a transmission line using a microstrip line with bulk type. But as the technique recently which can manufacture to have complex permittivity and permeability demanded using nonferrous metals for powder-type grows up, we need sensors and methods which can measure characteristics of powder-type materials. So far measuring methods of permittivity and permeability with waveguide or coaxial cable are used but they have faults which have a complex measurement method and are difficult to simultaneously measure permittivity and permeability. In this paper, a simultaneous measuring method of permittivity and permeability with 2-port coaxial cable and a new proposed calculation. The proposed 2-port coaxial cable is designed to be easy to insert materials and to have a wideband. We measure permittivity and permeability of magnetic powder(Ni-Fe-Mo, Ni-Fe) which reveal its characteristic at $0.3{\sim}1.3GHz$ to identify the proposed sensor.

• Journal of the Korean Chemical Society
• /
• v.32 no.6
• /
• pp.536-542
• /
• 1988

A nickel(Ⅱ) complex, Ni(IAA-NBz) (IAA-NBz') with ligand, N-benzylisonitrosoacetyl acetone imine (H-IAA-NBz) has been synthesized. This complex is very stable at room temperature and has cis-form and trans-form isomers. The ratio of nickel (Ⅱ) ion and ligand combined is 1 : 2. The elemental analysis, ir, nmr. electronic spectra and mass spectra have been studied. It is suggested from these studies that the isonitroso group of one ligand, H-IAA-NBz coordinates to nickel(Ⅱ)ion through the nitrogen atom to form five-membered ring, while that of the other ligand, H-IAA-NBz coordinates to nickel (Ⅱ) ion through the oxygen atom to form six-membered ring in square-planar complex.

• Journal of Industrial and Engineering Chemistry
• /
• v.68
• /
• pp.325-334
• /
• 2018

Lactose is a reducing disaccharide consisting of two different monosaccharides such as galactose and glucose. The hydrogenation of lactose to lactitol is a formidable challenge because it is a complex process and several side products are formed. In this work, we synthesized Ru-Ni bimetallic nanohybrids as efficient catalysts for selective lactose hydrogenation to give selective lactitol. Ru-Ni bimetallic nanohybrids with $Ru-NiO_x$ (x = 1, 5, and 10 wt%) are prepared by impregnating Ru and Ni salts precursors with $TiO_2$ used as support material. Ru-Ni bimetallic nanohybrids (represented as $5Ru-5NiO/TiO_2$) catalyst is found to exhibit the remarkably high selectivity of lactitol (99.4%) and turnover frequency i.e. ($374h^{-1}$). In contrast, monometallic $Ru/TiO_2$ catalyst shows poor performance with ($TOF=251h^{-1}$). The detailed characterizations confirmed a strong interaction between Ru and NiO species, demonstrating a synergistic effect on the improvement on lactitol selectivity. The impregnation-reduction method for the preparation of bimetallic $Ru-NiO/TiO_2$ catalyst promoted Ru nanoparticles dispersed on NiO and intensified the interaction between Ru and NiO species. $Ru-NiO/TiO_2$ efficiently catalyzed the hydrogenation of lactose to lactitol with high yield/selectivity at almost complete conversion of lactose at $120^{\circ}C$ and 55 bar of hydrogen ($H_2$) pressure. Moreover, $Ru-NiO/TiO_2$ catalyst could also be easily recovered and reused up to four runs without notable change in original activity.

• 한국신재생에너지학회:학술대회논문집
• /
• 2005.11a
• /
• pp.631-633
• /
• 2005

For biohydrogen production, hydrogenase is a key enzyme. In the present work we performed search of [NiFe]-hydrogenases from hydrogen producing microorganisms using degenerate polymerase chain reaction (PCR) strategy. Degenerate primers were designed from the conserved region of [NiFe]-hydrogenase group I especially on structural genes encoding for catalytic subunit of [NiFe]-hydrogenase from bacteria producing hydrogen. Most of [NiFe]-hydrogenase (group I) are expressed via complex mechanism with aid of auxiliary protein and localized through twin-arginine translocation pathway. [NiFe]-hydrogenase is composed of large and small subunits for catalytic activity. It is known that only small subunit has signal peptide for periplasmic localization and large & small subunitscome together before localization. During this process, large subunit is treated by endopeptidase for maturation. Based on these information we used signal peptide sequence and C-terminal of large subunit by recognized by endopeptidase as templates for degenerate primers. About 2,900 bp of PCR products were successfully amplified using the designed degenerate primers from genomic DNAs of several microorganisms. The amplified PCR products were inserted into T-vector and then sequenced to confirm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1998.11a
• /
• pp.25-28
• /
• 1998

Lithiated cobalt and nickel oxides are becoming very attractive as active cathode materials for secondary lithium ion secondary battery. $LiCoO_2$ is easily synthesized from lithium cobalt salts, but has a relatively high oxidizing potential on charge. LiNiOz is synthesized by a more complex procedure and its nonstoichiometry significantly degraded the charge-discharge characteristics. But $LiNiO_2$ has a lower charge potential which increases the system stability. Lithiated cobalt and nickel oxides are iso-structure which make the preparation of solid solutions of $LiNi_{1-x}Co_xO_2$ for O$LiCoO_2 and LiNiO_2$ electrode. The aim of the presentb paper is to study the electrochemical behaviour, as weU as the possibilities for practical application of layered Iithiated nickel oxide stabilized by $Co^{3+}$ substitution as active cathode materials in lithium ion secondary battery.