• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.363-368
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• 2006

This study selected the optimal catalyst for the process of producing $C_9$-alcohol by hydrogenating $C_9$-aldehyde, and carried out an experiment in order to establish the operating condition for maximizing the yield of $C_9$-alcohol. The BET surface area and the specific area of copper were most excellent in $CuO/ZnO/Al_2O_3$ (60:30:10 wt％) catalyst produced using acetate as a precursor of copper and $Na_2CO_3$ as a precipitant, and the catalyst also showed the highest performance in $C_9$-aldehyde hydrogenation. Using a trickle bed reactor loaded with optimized catalyst, we attained 94.1 wt％ yield of $C_9$-alcohol under the condition of $175^{\circ}C$, 800 psi and $WHSV=3hr^{-1}$. According to the result of comparing with other catalysts used in the hydrogenation of aldehyde, the catalyst showed similar performance to that of Ni/kieselghur and higher than that of $Cu-Ni-Cr-Na/Al_2O_3$ and $Ni-Mo/Al_2O_3$. According to the result of examining the stability of the catalyst through a long-term catalysis test, the yield of $C_9$-alcohol decreased slowly after around 72 hours due to the increasing production of high boiling-point byproducts.

• KSBB Journal
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• v.10 no.5
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• pp.561-567
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• 1995

Using superoxide dismutase (SOD)-deficient mutants of Saccharomyces cerevisiae, the oxygen toxicity induced by paraquat was studied. In aerobic culture condition, yeasts lacking MnSOD (milochondrial SOD) showed more significant growth retardation than CuZnSOD (cytoplasmic SOD)-deficient yeasts. However, not so big differences in growth pattern of those mutants compared with wild type were observed under anaerobic condition. When exposed to paraquat, the growth of yeasts lacking CuZnSOD was severely affected by higher than 0.01mM of paraquat in culture medium. By the analysis of several cellular components ivolved in free radical generating and scavenging system, it was found that, under aerobic condition, the content of lipid peroxides in cell membrane as well as cellular activity of glutathion peroxidase of CuZnSOD-deficient mutants was increased in the presence of paraquat, although significant decrease of catalase activity was observed in those stratns. In MnSOD-deficient yeast, however, increment in cellular activity of glutathion peroxldase and catalase by paraquat was observed without any deterioration of membrane lipid. It implies that the lack of mitochondrial SOD could be compensated by both of glutathion peroxldase and catalase, but that only glutathion peroxidase might act for CuZnSOD in cytoplasm. In contrast, all of SOD-deficient mutants showed a significant decrease in catalase activity, but slight increase in the activities of glutathion peroxidase, when cultivated anaerobically in the medium containing paraquat. Nevertheless, any significant changes of lipid peroxides in cell membranes were not observed during anaerobic cultivation of SOD-deficient mutants. It suggests that a little amount of free radicals generated by paraquat under anaerobic condition could be sufficiently overcome by glutathion peroxidase but not by catalase.

• Bulletin of the Korean Chemical Society
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• v.16 no.1
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• pp.33-36
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• 1995

Macrocyclic ligands have been studied as cation carriers in a supported liquid membrane system. Cd2+ has been transported using nitrogen substituted macrocycles as carriers and several divalent metal ions (M2+=Zn, Co, Ni, Cu, Pb, Mg, Ca, and Sr) have been transported using DBN3O2, DBN2O2and PolyNtnoen as carriers in a supported liquid membrane system. Competitive Cd2+-M2+ transport studies have also been carried out with the same system. Ligand structure, stability constant, membrane solvent and carrier concentration are also important parameters in the transport of metal ions.

• YAKHAK HOEJI
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• v.7 no.1
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• pp.26-29
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• 1963

Three systems such as CaS, BaS and ZnS are used as ground materials and transition elements such as Bi, Cu, Ag and Ni are used as activators to preared phosphorescent materials of strong after-grow intensity. These three systems in which we have 31 kinds of different composition samples are heated at given temperatures in the electrical furnace and are cooled in the air in order to crystallize them. In the case of BaS system, the mixture of CaO and purified S is better than the other kinds of calcium compound as the ground materials to crystallize phosphors. In BaS system, the mixture of BaCO$_{3}$ and purified S, in ZnS system ZnS respectively is the most proper ground material to prepare such a strong after-grow intensified phosphors. In a given range, the higher in temperature and the longer time of heating, the better phosphors we obtain.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.2
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• pp.92-92
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• 1996

Recently, with the rapid development in the oceanic systems such as the oceanic structures and vessel, there occurs much interest in the impingement erosion-corrosion. In this paper, Cu-metal was tested by using of erosion apparatus with water-jet type and was investigated under the behaviour of impingement erosion-corrosion according to various environmental conditions, and the properties of Cu-metal were evaluated through the measurement by weight loss, weight loss rate, protective efficiency. The results were compared with those obtained using Cu-metal applied to cathodic protection and Cu-alloys added to Zn or Al-metal. As a basis of those results, the best protective efficiencies could be taken as using cathodic protection method and Cu-alloy with Al & Zn material addings, and will be suggested as the fundamental data of the anti-impingement erosion-corrosion on Cu-metal of impeller material for oceanic centrifugal pump.

• Journal of the Korean Chemical Society
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• v.32 no.1
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• pp.30-36
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• 1988

The effect of high pressure on the stability of copper(II), cadmium(II) and zinc (II) complex ions with ethylenediamine, propylenediamine, diethylenetriamine has been investigated polarographically. 0.10M KN$O_3$ solution was used as a supporting electrolyte. The concentration of chelating agents was varied from 0.01M to 1.00M. The dissociation constants of metal complex ions were increased with increasing the pressure from 1 atmosphere to 1,500 atmospheres. The increment of the dissociation constant per unit atmosphere varied from 1.1 ${\times} 10^{-3}$% for Cu(dien)$_2^{2+}$ to 5.0 ${\times} 10^{-3}$ % for Zn(en)$_2^{2+}$.

• Analytical Science and Technology
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• v.13 no.2
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• pp.215-221
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• 2000

Analysis of fly ashes from the MSW incinerators was carried out using XRF, ICP-MS and ICP-AES. It was found that the major elements of fly ash were Ca, K, Na, Si, Al, S, Cl and O by the XRF analysis. The XRD spectra showed that the fly ashes were mainly consisted with the chlorides, hydroxides, carbonates and also oxides of former elements. For the determination of minor elements such as Zn, Pb, Cu, Cr, and Cd, we used ICP-AES and ICP-MS after microwave digestion and the results were compared with the result of XRF.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.399-399
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• 2011

본 논문에서는 Indium tin oxide (ITO) 투명전극의 성장온도($T_G$)가 Cu(In,Ga)$Se_2$ (CIGS) 박막태양전지에 미치는 영향을 살펴 보았다. ITO 박막은 radio-frequency magnetron sputtering을 이용하여 상온에서 $350^{\circ}C$까지의 다양한 $T_G$ 조건에서 i-ZnO/ glass와 i-ZnO/CdS/CIGS/Mo/glass 기판에 증착되었다. ITO의 비저항과 CdS/CIGS 계면 특성은 $T_G$에 크게 영향을 받았다. $T_G{\leq}200^{\circ}C$에서는 $T_G$가 증가할수록 ITO 저항이 감소하였고 이에 따른 series 저항 감소가 태양전지 성능 향상에 기여하였다. 하지만 $T_G$ > $200^{\circ}C$에서는 CdS 버퍼층의 Cd이 CIGS 층으로 확산되어 소자의 p-n 계면이 파괴되는 것을 발견하였다. $T_G=200^{\circ}C$에서 ITO를 증착한 CIGS 태양전지의 경우 가장 높은 광전변환효율을 보였다.

• Clean Technology
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• v.6 no.1
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• pp.61-69
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• 2000

In this study, generation process and properties of inorganic industrial waste which can be used in cement industry were investigated. The scheme of recycling to use the selected waste as raw materials, mineralizer and flux, admixture and raw materials for special cement was decided and then various experiments were carried out. The experimental results were as follows ; In the use of industrial waste as raw materials, ferrous materials could be substituted by Cu-slag, Zn-slag, electric arc furnace or convertor furnace slag etc., and a siliceous material could be substituted by sand from cast-iron industry. By-products from sugar or fertilizer industry, which has $CaF_2$ as the main component, and jarosite from Zn refinery enabled clinker phases to be formed at lower temperature by $100{\sim}150^{\circ}C$. Adding Cu slag and STS sludge in proper proportion to cement improved properties of cement. Fly ash and limestone powder as admixture had the same effect on cement. As a raw material for special cement, aluminium waste sludge could be used in making ultra early strength cement, which had the compressive strength of $300kg/cm^2$ within 2hours. And two different ashes from municipal incinerator could be raw materials of the cement which was mainly composed of $C_3S$ and $C_{11}A_7{\cdot}CaCl_2$ as clinker phases.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.87-93
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• 2003

Growth and mineral composition of young radish in soil amended with sewage sludge (ISS) with or without liming were investigated. Levels of EC, T-N, and micronutrients were increased in the ISS treatment (50 Mg/ha) compared to the NPK treatment but those of available P and exchangeable cations were decreased. Chlorosis was appear on the young radish leaf at the ISS treatment, but this phytotoxic symptom was corrected with lime amendment (3 Mg/ha). Yields of young radish leaf and root in the combined treatment of ISS and lime were increased about 29 and 48%, respectively, compared with those in the ISS treatment. Contents of P, K, Ca, and Mg in young radish were higher in the combined treatment to ISS and lime, whereas those contents in the ISS treatment were lower than those in the NPK treatment. Contents of Cu, Zn, and Ni in soil and young radish leaf were positively correlated with total N content in young radish leaf, while contents of P, K, Ca, and Mg were negatively correlated. Contents of Cu, Zn, and Ni in leaf were negatively correlated with yield of young radish. Contents of Cu and Zn in leaf corresponding with a 5% yield reduction of young radish were 22.4 and 349 mg/kg, respectively.