• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.1039-1041
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• 2002

• Bulletin of the Korean Chemical Society
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• v.17 no.5
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• pp.414-416
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• 1996

• Bulletin of the Korean Chemical Society
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• v.18 no.1
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• pp.117-119
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• 1997

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2029-2032
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• 2014

Magnetically nano-$CoFe_2O_4$ efficiently catalyzes oxidation of primary and secondary benzylic and aliphatic alcohols to give the corresponding carbonyl products in good yields. The reactions were carried out in an aqueous medium at room temperature in the presence of oxone (potassium hydrogen monopersulfate) as an oxidant. In addition, the catalysts could be reused up to 6 runs without significant loss of activities. Catalyst was characterized by SEM, XRD and IR.

• Bulletin of the Korean Chemical Society
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• v.17 no.7
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• pp.625-630
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• 1996

The cobalt-substituted polyoxotungstate [(CoPW11O39)5-] has been used as a catalyst in olefin epoxidation and alkane hydroxylation reactions. The epoxidation of olefins by iodosylbenzene in CH3CN yielded epoxides predominantly with trace amounts of allylic oxidation products. cis-Stilbene was streoselectively oxidized to cis-stilbene oxide with small amounts of trans-stilbene oxide and benzaldehyde formation. The epoxidation of carbamazepine (CBZ) by potassium monopersulfate in aqueous solution gave the corresponding CBZ 10,11-oxide product. Other transition metal-substituted polyoxotungstates (M=Mn2+, Fe2+, Ni2+, and Cu2+) were inactive in the CBZ epoxidation reaction. The cobalt-substituted polyoxotungstate also catalyzed the oxidation of alkanes with m-chloroperbenzoic acid to give the corresponding alcohols and ketones. The presence of CH2Br2 in the hydroxylation of cyclohexane afforded the formation of bromocyclohexane, suggesting the participation of cyclohexyl radical. In the 18O-labeled water experiment, there was no incorporation of 18O into the cyclohexanol product when the hydroxylation of cyclohexane by MCPBA was carried out in the presence of H218O. Some mechanistic aspects are discussed as well.

• Journal of Food Hygiene and Safety
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• v.37 no.5
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• pp.317-322
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• 2022

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA), a chronic contagious disease in small ruminants. The prevalence of CLA has been reported to be >50% in Korean black goats. CLA is difficult to control due to a lack of efficient vaccines and treatment methods. Effective disinfection of the farm environment may be an alternative strategy for reducing the spread of C. pseudotuberculosis. The objective of this study was to evaluate the efficacy of commercial disinfectants against CLA. The six commercial disinfectants, largely composed of sodium dichloroisocyanurate, sodium hypochlorite, potassium monopersulfate triple salt, quaternary ammonium, citric acid, and copper sulfate, were tested against five different genotypes of C. pseudotuberculosis isolated from goat farms in Korea. Efficacy tests were performed in accordance with the disinfectant efficacy test guidelines recommended by the Animal and Plant Quarantine Agency of Korea with slight modifications. All disinfectants except for copper sulfate exhibited >99.99% killing efficacy under hard water conditions following 30 min of incubation, which is the recommended standard treatment time according to guidelines. The minimum bactericidal treatment time was evaluated by employing treatments for durations of 1, 5, and 15 min. The most effective compounds under hard water conditions were sodium dichloroisocyanurate, potassium monopersulfate triple salt, and sodium hypochlorite, exhibiting >99.99% killing efficacy after 1 min of treatment. In the aqueous solution forms, citric acid and the quaternary ammonium compound were the most effective, but required at least 5 min to kill >99.99% of the bacteria. The current study characterizes the killing efficacy of six commercial disinfectant active compounds against C. pseudotuberculosis. Thus, this study provides essential information regarding the efficacy of the disinfectants used to control CLA in goat farms.

• Korean Journal of Poultry Science
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• v.49 no.4
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• pp.287-298
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• 2022

This study evaluated the efficacy of chlorine dioxide (ClO₂) as an oxidant to reduce malodor emission from chicken feces. Two experiments were performed with the following four treatments in parallel: 1) fresh chicken feces with only distilled water added as a control, 2) a commercial germicide as a positive control, and 3) 2,000 or 4) 3,000 ppm of ClO₂ supplementation. Aluminum gas bags containing chicken feces sealed with a silicone plug were used in both experiments, and each treatment was tested in triplicate. In Experiment 1, 10 mL of each additive was added on the first day of incubation, and malodor emissions were then assessed after 10 days of incubation. In Experiment 2, 1 mL of each additive was added daily during a 14-day incubation period. At the end of the incubation, gas production, malodor-causing substances (H₂S and NH₃ gases), dry matter, pH, volatile fatty acids (VFAs), and microbial enumeration were analyzed. Supplementing ClO₂ at 2,000 and 3,000 ppm significantly reduced the pH and the ammonia-N, total VFA, H₂S, and ammonia gas concentrations in chicken feces compared with the control feces (P<0.05). Additionally, microbial analysis indicated that the number of coliform bacteria was decrease after ClO₂ treatment (P<0.05). In conclusion, ClO₂ at 2,000 and 3,000 ppm was effective at reducing malodor emission from chicken feces. However, further studies are warranted to examine the effects of ClO₂ at various concentrations and the effects on malodor emission from a poultry farm.