• Clean Technology
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• v.9 no.2
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• pp.63-69
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• 2003

The metal finishing industry generates a variety of pollutants such as acidic or alkaline wastewater, chromic compounds, cyanide, heavy metals, and toxic materials. Especially, zinc plating process is one of the processes which cause serious environmental problems. In this study, we applied the proven optimum technology to important unit processes in terms of implement effects through the process diagnosis and analysis. This study aimed to improve the working environment and the environmental pollutions in zinc plating process.

• Journal of Environmental Science International
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• v.3 no.4
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• pp.439-443
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• 1994

In aqueous acid solution ${[Cr(CN)_6]}^{3-}$ aquates via a series of stepwise stereospecific reactions to give ${[Cr{(H_2O)}_6]}^{3+}$as the final product.Some of the intermediate cyanoaquo complexes in the sequence have been isolated.These complexes aquate by both acid independent and acid denpendent pathways, the latter involving protonation of the cyano ligands followed by aquation of the singly protonated species. The kinetic data for the aquation of {[CrCN{(H_2O)}_5]}^{2+}$ are consistent with the transition state structure ${[{(H_2O)}_4Cr(CN)-OH-Cr{(H_2O)}_5]}^{3+}$. Addition of $Cr^{2+}$ to solutions of cyanocobalt(III) complexes produces the metastable intermediate${[CrNC{(H_2O)}_5]}^{2+}$ This isomerizes to in a $Cr^{2+}$-catalyzed reaction which occurs by a ligand-bridged electron-change mechnism. From acid catalysis on these aquation reactions, it product HCN. Especially, $HSO_3$-ions do the role of catalyst in the formation of HCN from $CrCN^{3-}$

• Journal of Korean Society of Water and Wastewater
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• v.21 no.3
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• pp.279-285
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• 2007

Toxicity evaluations using oxygen uptake rate (OUR) on activated sludge process were investigated. On toxicity evaluations of heavy metals, all toxicants in experiments decreased OUR with respect to the concentrations of the toxicants, while high toxicities with cyanide and mercury were observed respectively. On toxicity evaluations of composite heavy metals, composite toxicities had similar results as to the total sum of each toxicants that presents accurate toxicity evaluation using OUR. From these results, it is concluded that activated sludge is effective indicator for toxicity evaluation on wastewater of biological treatment plants.

• The Korean Journal of Mycology
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• v.20 no.1
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• pp.51-57
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• 1992

Mitochondria in Pleurotus ostreatus were isolated and purified by stepped sucrose density gradient centrifugation, to compare the effects of organic compound on the activities of mitochondrial ATPase in Basidiomycotina with those in mammalian cell. The effects of N, N'-dicycio-hexylcarbodiimide (DCCD), carbonyl cyanide m-chlorophenylhydrazone (CCCP), sodium azide and aurovertin known as compounds to be related to electron transfer system in mitochondria were studied. A activity of mitochondrial ATPase was inhibited by 64%, 57% and 53% in the presence of 0.25 mM DCCD, 0.02 mM sodium azide and 1.5 $({\mu}g/mg\;of\;protein)$ aurovertin B, respectively. It was stimulated by 22% in the presence of 0.15 ${\mu}M$ CCCP.

• The Korean Journal of Physiology
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• v.5 no.2
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• pp.9-14
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• 1971

The direct effects of various agents on the phosphorylase activity of rat kidney was studied in vitro and the results were summarized as follows. 1. The kidney phosphorylase activity was markedly depressed by iodoacetic acid whereas it was increased by sodium azide. 2. DNP had no effect on the phosphorylase activity, while sodium cyanide slightly increased the activity of the enzyme. 3. Ouabain slightly depressed the phosphorylase activity whereas it was markedly depressed by oligomycin. 4. Vasopressin and histamine markedly increased the phosphorylase activity.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.189-194
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• 1998

Geochemical study was carried out to find out the distribution of metals and cyanide in soil in the vicinity of the abandoned Keum-Jung mine. Chemical analysis showed that content of As in soil around tailings exceeded 15mg/kg, Korean standard of soil contamination in the farm land. That means the contamination of soil by As is due to input of tailings. According to total decomposition of tailings, As was highly concentrated in tailings. However the water in tailings impoundment was changed to acidic and contaminated by metal and sulfate because the tailings in the top of the tailings impoundment had been oxidized. Acid mine drainage contaminated the water course in the vicinity of the paddy soils. The proper measures are required to prevent contamination of the soil and water in the vicinity of the Keum-Jung mine.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.432-437
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• 1992

When $H^{2}$ was provided as the electron donor, optimum $O_{2}$ levels for growth of Wolinella succinogenes ATCC 29543 were 2% and 8% on brucella agar and in brucella broth, respectively. No growth occurred under 21% $O_{2}$, and scant or no growth occurred under anaerobic condition. $O_{2}$ uptake was inhibited by cyanide and 2-heptyl-4-hydroxyquinoline N-oxide. Protons were translocated out of the cell when oxygen was used as the terminal electron accetor. The $H^{+}$/O ratio with $H_{2}$ and formate as an electron donor were 1, 97 and 1.49, respectively. Proton translocation was inhibited by the protonophore carbonylcyanide m-chlorophenylhydrazone.e.

• Bulletin of the Korean Chemical Society
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• v.29 no.10
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• pp.2029-2032
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• 2008

• Journal of Environmental Health Sciences
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• v.31 no.1
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• pp.61-65
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• 2005

The oxidative transformation of triclosan with laccase from Trametes versicolor was conducted in a closed, temperature controlled system containing phosphate buffer for pH control. The optimum pH for triclosan transformation showed about 5. Despite the observation that elevated temperatures tended to inactivate the enzyme, increased transformation of triclosan was observed up to $50^{\circ}C$. Of the mediators studied, ABTS was most successful at enhancing triclosan transformation. About 80% of the toxicity of the initial mixture was reduced after the enzymatic treatment. In the presence of 1.0 mM of anions such as sulfite, sulfide, and cyanide, triclosan transformation was greatly inhibited. Chloride and fluoride ions exhibited inhibition of triclosan transformation at 25 mM. Ferric ion substantially inhibited triclosan transformation at 1.0 mM.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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• pp.1-6
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• 2016

In this article, the recent developments in electroless plating of copper, electroless bath formulation and effect of plating parameters have been reviewed. Cyanide free electroless baths are now being developed and studied due to the various environmental concerns. Various organic chemicals such as complexing agents, reducing agents, and additives such as poly-alcohols and aromatic ring compounds have been added to copper plating baths for promising results. The effects of various reducing and complexing agents, bath conditions like additives, bath pH, and composition have been summarized. Finally the applications of the electroless plating of copper and latest developments have been overviewed for further guidance in this field.