• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.286-292
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• 1997

This study was undertaken to evaluate an antioxidative activity of silymarin and silybin obtained from Silybum marianum against oxidation of human low density lipoprotein (LDL). The electrophoretic mobility observed apparently was higher phase for LDL oxidized by macrophages compared to native LDL. Silymarin and silybin inhibited the copper-catalysed oxidation of human LDL in a dose-dependent manner. Silymarin and silybin at the concentration of 50 $\mu$M/ml also inhibited the copper catalysed oxidation of LDL induced by the cell J774 and macrophages. LDL reisolated from the cell incubation in the presence of silymarin or silybin was degraded at rates similar with native LDL. Silymarin or silybin found to be potential inhibitors against oxidation of $^{125}$I-LDL by macrophages and endothelial cells.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.622-626
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• 2005

The Residual stress is stress at the inside of materials after plastic deformation. Certainly, this residual stress have an effect on fatigue life. Therefore, it is very important that understanding residual stress at the inside of materials. But in case of U-shaped Pipe that it is dealt with a mailer in this paper, distribution of residual stress is very complicated and exactly become unknown caused by difficulty of measurement. Then, in this paper, we are evaluated residual stress at in the inside of materials by finite clement method program and verified validity by test.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.444-446
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• 1999

The structure and composition of anodic films, formed on 6063 commercial aluminium alloy at constant current density of $1.5A/^dm2$ with various superimposed cathodic current ratio, in the range 0~33%, in the 11% $H_2SO_4$ with various concentration of $CuSO_4{\cdot}5H_2O$, in the range 0~75 g/l, without cathodic current are generally porous-type and no sign of Cu co-deposition appearance, suggesting that cathodic current is an important factor in the Cu co-deposition. Comparison with the anodic film thickness measurement results obtained from anodic film formed by direct anodic current and anodic film formed by superimposed various portion of cathodic current, the portion of cathodic current of input current increases with decrease of anodic film thickness and increases with increase of concentration of $Cu_2S{\;}and{\;}Cu_2O$ in the anodic film.

• Bulletin of the Korean Chemical Society
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• v.12 no.3
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• pp.276-281
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• 1991

Electrochemical behaviors of optically active sparteine-Cu(II) dihalide complexes were investigated by polarography and cyclic voltammetry (CV). These Cu(II) complexes are rather easier to be reduced to Cu(I) states when comparison is made with other nonplaner copper complexes, We have assigned the CV peaks and polarographic waves related to the redox processes for these complexes. We could also observe the exchange reaction of Cu(II) ion in the complex with mercury metal in the cell having mercury pool. The redox mechanism of these complelxes is as follows; The 1st wave appeared at +0.47 V/+0.65 V corresponds to the reaction of $SpCuX_2+ e{\rightleftarrow}SpCuX_{2^-}$ and the 2nd one at +0.26 V/+0.21 V does the reaction of $SpCuX_{2 ^-} +e{\rightleftarrow}SpCuX_2^{2-}$. The 3rd one at -0.35 V/-0.27 V is dueto the reduction of mercury complex formed via exchange reaction. Where, X is chloride ion.

• Bulletin of the Korean Chemical Society
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• v.20 no.3
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• pp.352-354
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• 1999

The spectrophotometric determination of Cu(Ⅱ) with α-(2-benzimidazolyl)-α',α"-(N-5-nitro-2-pyridylhydrazone)-toluene has been investigated. The optimum conditions of pH, stability, concentration of ligand and surfactant were evaluated. This method is a simple and sensitive method for determination of Cu(Ⅱ) and offers a selective separation of Cu(Ⅱ) from sample solution containin- I ppm below amount of Ni(Ⅱ), Co(Ⅱ), Zn(Ⅱ) and Sn(Ⅱ). Copper was determined by measuring the absorbance of Cu(Ⅱ)-BINPHT complex extracted with benzene in Brij 58 surfactant at 410 nm. Beer's law is obeyed over the concentration range 0∼2.5 μgmL-1 and the detection limit (S/N=2) is 0.06 μgmL-1. The relative standard deviation at the 0.3 μgmL-1 is 2.4% (N=7). The method was applied for the determination of Cu(Ⅱ) in various milks.

• Resources Recycling
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• v.6 no.3
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• pp.41-45
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• 1997

The recovery of tellurium from Te-cement obtained during the processing of copper anode slimes was carried out by a series of hydrometallurgical processes, i.E. leaching Te-cement in NaOH solution, precipitation of impurities with the addition of ${Na}_{2}S$ followed by direct electrowinning of tellurium in NaOH solution. The optimum conditions for each process were determined and discussed in terms of various parameters associated with each step to maximize the recovery and purity of tellurium. The final purity of tellurium from electrownning in alkaline solution was found to be more than 99.9%.

• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.208-214
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• 1989

A method for the simultaneous determination of copper and cobalt by spectrophotometry has been described. The procedure involves the co-extraction of Cu(Ⅱ) and Co(Ⅱ) from 0.3M HCl into methyl isobutyl ketone as the ion-pairs formed between their thiocyanate complexes and high molecular alkylamines such as Amberlite LA1, Alamine 336, and Aliquat 336. The extract shows the color development to have the maximum absorbances at two different wavelengths i.e., 480 nm for copper and 625 nm for cobalt. Since the spectra of the ion-pairs overlap each other, two simultaneous equations are used to obtain the concentrations from absorbances. Even small amount of Fe(Ⅲ) and Ni(Ⅱ) interferes with the determination of copper. The results of the analysis of samples are in good agreement with the results determined by separate methods within RSD 5.9%.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.794-798
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• 1999

An experiment was conducted to determine the effects of supernormal level of copper (Cu) from different supplementary sources on the performance, cholesterol level in plasma and breast muscle, and accumulation of fat and Cu in broilers. In a 5 wk feeding trial, two hundred forty hatched male broiler chickens were assigned to four dietary treatments: control diet containing 10 mg/kg supplementary Cu, control diet plus 250 mg/kg Cu from $CuSO_4$ ($CuSO_4-250$), control diet plus 125 mg/kg Cu from Cu-methionine chelate (Cu-Met-125), and control diet plus 250 mg/kg Cu from Cu-methionine chelate (Cu-Met-250). Weight gain in Cu-Met-125 treatment and Cu-Met-250 treatment were not different, but they were significantly (p<0.05) greater than that in $CuSO_4-250$ treatment. Plasma total cholesterol and reduced glutathione (GSH) in blood were significantly reduced by supplementation of $CuSO_4-250$, but were not significantly affected by Cu-Met supplementations. Plasma HDL cholesterol, plasma triglycerides and breast muscle cholesterol were not significantly affected by Cu supplementation. $CuSO_4-250$ improved metabolizability of crude fat, which resulted in low abdominal fat pad weight. Cu from Cu-Met was better absorbed and accumulated more in the breast muscle and lesser in the liver compared with Cu from $CuSO_4$.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.41.2-41.2
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• 2011

Recently, scaling down of ULSI (Ultra Large Scale Integration) circuit of CMOS (Complementary Metal Oxide Semiconductor) based electronic devices become much faster speed and smaller size than ever before. However, very narrow interconnect line width causes some drawbacks. For example, deposition of conformal and thin barrier is not easy moreover metallization process needs deposition of diffusion barrier and glue layer. Therefore, there is not enough space for copper filling process. In order to overcome these negative effects, simple process of copper metallization is required. In this research, Cu-V thin alloy film was formed by using RF magnetron sputter deposition system. Cu-V alloy film was deposited on the plane $SiO_2$/Si bi-layer substrate with smooth and uniform surface. Cu-V film thickness was about 50 nm. Cu-V layer was deposited at RT, 100, 150, 200, and $250^{\circ}C$. XRD, AFM, Hall measurement system, and XPS were used to analyze Cu-V thin film. For the barrier formation, Cu-V film was annealed at 200, 300, 400, 500, and $600^{\circ}C$ (1 hour). As a result, V-based thin interlayer between Cu-V film and $SiO_2$ dielectric layer was formed by itself with annealing. Thin interlayer was confirmed by TEM (Transmission Electron Microscope) analysis. Barrier thermal stability was tested with I-V (for measuring leakage current) and XRD analysis after 300, 400, 500, 600, and $700^{\circ}C$ (12 hour) annealing. With this research, over $500^{\circ}C$ annealed barrier has large leakage current. However V-based diffusion barrier annealed at $400^{\circ}C$ has good thermal stability. Thus, thermal stability of vanadium-based thin interlayer as diffusion barrier is good for copper interconnection.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.348-354
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• 2009

Copper(II) complexes with tetraoxo dithia tetraaza macrocyclic ligands; [18]ane$N_4S_2$: 1,4,10,13-tetraaza-5,9,14,18-tetraoxo-7,16-dithia-cyclooctadecane, [20]ane$N_4S_2$: 1,5,11,15-tetraaza-6,10,16,20-tetraoxo-8,18-dithia-cyclocosane,Bzo2[18]ane$N_4S_2$: dibenzo-1,4,10,13-tetraaza-5,9,14,18-tetraoxo-7,16-dithia-cyclooctadecane, Bzo2[20]ane$N_4S_2$: dibenzo-1,5,11,15-tetraaza-6,10,16,20-tetraoxo-8,18-dithia-cyclocosane; were entrapped in the nanopores of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of [bis(diamine)copper(II)] (diamine = 1,2-diaminoethane, 1,3-diaminopropane, 1,2-diaminobenzene, 1,3-diaminobenzene); $[Cu(N-N)_2]^{2+}$-NaY; in the nanopores of the zeolite, and (ii) in situ template condensation of the copper(II) precursor complex with thiodiglycolic acid. The obtained complexes and new host-guest nanocomposite materials; $[Cu([18]aneN_4S_2)]^{2+}-NaY,\;[Cu([20]aneN_4S_2)]^{2+}-NaY,\;[Cu(Bzo_2[18]aneN_4S_2)]^{2+}-NaY,\;[Cu(Bzo_2[20]aneN_4S_2)]^{2+}$-NaY; have been characterized by elemental analysis FT-IR, DRS and UV-Vis spectroscopic techniques, molar conductance and magnetic moment data, XRD and, as well as nitrogen adsorption. Analysis of data indicates all of the complexes have been encapsulated within nanopore of zeolite Y without affecting the zeolite framework structure.