• Membrane Journal
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• v.32 no.6
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• pp.456-464
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• 2022

Hydrogen permeation performance was analyzed by manufacturing Pd and Pd-Cu membranes through electroless plating. As a support for the Pd and Pd-Cu membranes, α-Al₂O₃ ceramic hollow fiber were used. Pd-Cu membrane was manufactured through sequential electroless plating, and then annealing was performed at 500°C, for 18 h in a hydrogen atmosphere to make Pd and Cu alloy. After annealing, the Pd-Cu membrane confirmed that the alloy was formed through EDS (Energy Dispersive X-ray Spectroscopy) and XRD (X-ray Diffraction) analysis. In addition, the thickness of the Pd and Pd-Cu plating layers were measured to be about 3.21 and 3.72 µm, respectively, through SEM (Scanning Electron Microscope) analysis. Hydrogen permeation performance was tested for hydrogen permeation in the range of 350~450°C and 1~4 bar in hydrogen single gas and mixed gas (H₂, N₂). In a single hydrogen gas, Pd and Pd-Cu membranes have flux of up to 54.42 and 67.17 ml/cm²⋅ min at 450 °C and 4 bar. In the mixed gas, it was confirmed that the separation factors of 1308 and 453 were obtained under the conditions of 450 °C and 4 bar.

• International Journal of Industrial Entomology and Biomaterials
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• v.39 no.2
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• pp.67-73
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• 2019

The genomic structure of the Cu/Zn superoxide dismutase (SOD1) gene from the entomopathogenic fungus, Cordyceps pruinosa was characterized. The SOD1 gene of C. pruinosa spans 947 nucleotides and consisted of four exons encoding for 154 amino acids and three introns. Four exons of the SOD1 gene are composed of 13, 331, 97 and 20 nucleotides respectively. Homology search of amino acid sequences of the SOD1 gene of C. pruinosa with another 13 fungi species showed higher sequence similarity of 69% ~ 95% and had the most highest sequence identity of 95% with Beauveria bassiana and Cordyceps militaris, which can easely infect domesticated Bombyx mori and another wild lepidopteran species in artificial or natual manner of infection. This SOD1 gene sequence showed copper, zinc and beta-barrel fold sites. Homology search showed that the Cu/Zn SOD1 gene from the entomopathogenic fungus, C. pruinosa is an orthologous gene homolog present in different species of organism whose ancestor predates the split between the relating species. In addition, C. pruinosa SOD1 gene is placed together within the ascomycetes group of fungal clade. From these results it is concluded that C. pruinosa SOD1 gene is orthologous gene having the same or very similar functions with a common evolutionary ancestor.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.996-1005
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• 2017

In this paper, nuclear data for cross sections of the $^{64}Zn(n,2n)^{63}Zn$, $^{64}Zn(n,3n)^{62}Zn$, $^{64}Zn(n,p)^{64}Cu$, $^{66}Zn(n,2n)^{65}Zn$, $^{66}Zn(n,p)^{66}Cu$, $^{67}Zn(n,p)^{67}Cu$, $^{68}Zn(n,p)^{68}Cu$, and $^{68}Zn(n,{\alpha})^{65}Ni$ reactions were studied for neutron energies up to 40 MeV. In the nuclear model calculations, TALYS 1.6, ALICE/ASH, and EMPIRE 3.2 codes were used. Furthermore, the nuclear data for the (n,2n) and (n,p) reaction channels were also calculated using various cross-section systematics at energies around 14-15 MeV. The code calculations were analyzed and obtained using the different level densities in the exciton model and the geometry-dependent hybrid model. The results obtained from the excitation function calculations are discussed and compared with literature experimental data, ENDF/B-VII.1, and the TENDL-2015 evaluated data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4660-4665
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• 2011

New precursors as a Li adsorbent, $Li_{1.6}(MnM)_{1.6}O_4$ (M=Cu, Ni, Co, Fe), were synthesized by hydrothermal method and their physicochemical properties were discussed. XRD and HRTEM results revealed that the original spinel structure was stabilized by cobalt-doping while Cu-, Ni- and Fe-doping led to structural changes. Such a structural stabilization by Cobalt-doping was maintained after lithium leaching by acid treatment. Li absorption efficiency from seawater was significantly enhanced by using the Cobalt-doped spinel manganese oxide, $Li_{1.6}[MnCo]_{1.6}O_4$, compared to the commercially available $Li_{1.33}Mn_{1.67}O_4$; the adsorbed amount of Li from 1g-adsorbent was 35 and 16 mg by $Li_{1.6}[MnCo]_{1.6}O_4$, and $Li_{1.33}Mn_{1.67}O_4$, respectively.

• Journal of Environmental Health Sciences
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• v.13 no.1
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• pp.67-71
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• 1987

This study was intended to investigate the content of Cu, Mn, Zn in the dried milk powders except infant formula milkpowder from January to March, 1986. The content of the trace metals was determined by Atomic Absorption Spectrophotometry. The results were as follows: 1. Averages of Cu, Mn, Zn in the total samples were Cu, 0.3043 ppm Mn, 0.5101 ppm Zn, 26.006 ppm. 2. Averages and ranges of Cu, Mn, Zu in the whole milk powder were Cu, 0.2483, 0.216 - 0.48 Mn, 0.552 ppm, 0.336 - 0.732 ppm Zn, 28.961 ppm, 7.5 - 51.9 ppm. 3. Averages and ranges of Cu, Mn, Zn in the skim milk powder were Cu, 0.4095 ppm, 0.3 - 0.54 ppm Mn, 0.6907 ppm, 0.348 - 0.84 ppm Zn, 38.381 ppm, 30.6 - 55.2 ppm. 4. Averages and ranges of Cu, Mn, Zn in the modified milk powder were Cu, 0.3459 ppm, 0.12 0.948 ppm Mn, 0.2414 ppm, 0.096 - 0.348 ppm Zn, 7.752 ppm, 1.2 - 17.002 ppm. 5. It showed the highest amount of Cu, Mn, Zu in the skim milk powder group than in the other group and the lowest amount of Cu in the whole milk powder group and Mn, Zn in the modified milk group.

• Korean Journal of Materials Research
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• v.17 no.2
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• pp.61-67
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• 2007

The magnetron reactive sputtering was adopted to deposit CuO buffer layers on the polyimide surfaces for increasing the adhesion strength between Cu thin films and polyimide, varying $O_2$ gas flow rate from 1 to 5 sccm. The CuO oxide was formed through all the $O_2$ gas flow rates of 1 to 5 sccm, showing the highest value at the 3 sccm $O_2$ gas flow rate. The XPS analysis revealed that the $Cu_2O$ oxide was also formed with a significant ratio during the reactive sputtering. The adhesion strength is mainly dependent on the amount of CuO in the buffer layers, which can react with C-O-C or C-N bonds on the polyimide surfaces. The adhesion strength of the multi-layered Cu/buffer layer/polyimide specimen decreased linearly as the heating temperature increased to $300^{\circ}C$, even though there showd no significant change in the chemical state at the polyimide interface. This result is attributed to the decrease in surface roughness of deposited copper oxide on the polyimide, when it is heated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1992.11a
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• pp.67-72
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• 1992

In this paper, We prepared the thin film Cu-doped CdS Photovoltaic Cell, varying deposition condition by E-beam process and investigated its properties. After the Cu/CdS films were deposited on transparent ITO glass. We heat-treated to diffuse Cu atoms to CdS fi1m at 350[$^{\circ}C$]. With deposited Cu-doped CdS film. We investigated the electrical. optical. X-ray diffraction and junction property. We studied how to prepare the High conversion efficiency Solar cell window layer.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.446-452
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• 2000

This study was carried out to investigate the effect of mine activity on paddy fields, agricultural water, and plants in the ruined Oksung Cu-Zn mine area. Soil samples collected from paddy fields adjacent to the Cu-Zn mine sites were sequentially extracted and determined the contents of heavy metals such as Cd, Zn, Cu, Pb, Cr and Ni. Distribution of exchangeable heavy metals in soils was 30.2% of Cd, 11.3% of Zn, 2.2% of Cu, 4.6% of Cr, 0.6% of Pb and 3.9% of Ni. Water soluble heavy metals were only detected with Zn. The contents of heavy metals in water collected from the mine were 0.01 of Cd, 27.35 of Zn, 4.86 of Cu, 1.04 of Pb, 0.03 of Cr and $0.08mg\;L^{-1}$ of Ni. while the contents in waler collected out of the mine were 16.67 of Zn, 0.59 of Cu, 0.49 of Pb, 0.05 of Cr and $0.06mg\;L^{-1}$ of Ni. On the other hand, agricultural water near mine area were 1.26 of Zn, 0.05 of Cu, 0.05 of Pb and $0.02mg\;L^{-1}$ of Ni. Both Cd and Cr were not detected in the agricultural water.

• Journal of Environmental Science International
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• v.30 no.1
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• pp.57-67
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• 2021

Photocatalytic green energy H2 production utilizing inexhaustible solar energy has been considered as a potential solution to problems of energy scarcity and environmental contamination. However, the design of a cost-effective photocatalyst using simple synthesis methodology is still a grand challenge. Herein, a low-cost transition metal, Cu-loaded one-dimensional TiO2 nanorods (Cu/TNR) were fabricated using an easy-to-use synthesis methodology for significant H2 production under simulated solar light. X-ray photoelectron spectral studies and electron microscopy measurements provide evidence to support the successful formation of the Cu/TNR catalyst under our experimental conditions. UV-vis DRS studies further demonstrate that introducing Cu on the surface of TNR substantially increases light absorption in the visible range. Notably, the Cu/TNR catalyst with optimum Cu content, achieved a remarkable H2 production with a yield of 39,239 µmol/g after 3 h of solar light illumination, representing 7.4- and 27.7-fold enhancements against TNR and commercial P25, respectively. The notably improved H2 evolution activity of the target Cu/TNR catalyst was primarily attributed to its excellent separation and efficiently hampered recombination of photoexcited electron-hole pairs. The Cu/TNR catalyst is, therefore, a potential candidate for photocatalytic green energy applications.

• Journal of the Korean Vacuum Society
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• v.12 no.2
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• pp.136-143
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• 2003

In this paper, high purity RF sputter-type ion source for non-mass separated ion beam deposition was evaluated. The fundamental characteristics of the ion source which is composed of an RF Cu coil and a high purity Cu target (99.9999 %) was studied, and the practical application of Cu thin films for ULSI metallization was discussed. The relationship between the DC target current and the DC target voltage at various RF power and Ar gas pressures was measured, and then preparation conditions for Cu thin films was described. As a result, it was found that the deposition conditions of the target voltage, the target current and the Ar pressure were optimized at -300 V, 240 W and 9 Pa, respectively. The resistivity of Cu films deposited at a bias voltage of -50 V showed a minimum value of 1.8 $\pm$ 0.1 $mu\Omega$cm, which is close to that of Cu bulk (1.67 $mu\Omega$cm).