• Korean journal of applied entomology
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• v.54 no.3
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• pp.151-158
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• 2015

Chlorine dioxide ($ClO_2$) can be used as a fumigant to kill insects. However, some insects can exhibit an evasive behavior from chlorine dioxide. This evasive behavior decreases the efficiency of the insecticidal activity of chlorine dioxide. This study tested a hypothesis that heat treatment suppresses the evasive behavior and synergizes the control efficacy of chlorine dioxide. Chlorine dioxide fumigation killed the red flour beetle, Tribolium castaneum, under direct exposure condition to the chemical for 12 h with median lethal concentrations of 383.67 ppm (153.63 - 955.78 ppm: 95% confidence interval) for larvae and 397.75 ppm (354.46 - 446.13 ppm: 95% confidence interval) for adults. However, when they were treated with enough diet flour, they exhibited an evasive behavior by entering the diet, which significantly decreased the control efficacy of the fumigant. To clarify the evasive behavior, the choice test of the adults were performed in Y tube arena. The test adults significantly avoided the diet treated with chlorine dioxide, while the antennatectomized adults lost the avoidance behavior. Heat treatment using $46^{\circ}C$ for 6 h killed only 10% or less of T. castaneum. Interestingly, most adults were observed to come out of the diet under the heat treatment. Chlorine dioxide treatment even at 400 ppm for 6 h did not kill any T. castaneum. However, the combined treatment of chlorine dioxide with the heat treatment for 6 h resulted in 95% mortality. These results indicated that heat treatment suppressed the evasive behavior of T. castaneum and synergized the control efficacy of the chlorine dioxide fumigant.

• Journal of Internet of Things and Convergence
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• v.6 no.2
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• pp.19-24
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• 2020

In the present study, using biological information of bacteria and biochemical information of chlorine dioxide gas, Gram-positive bacteria, e.g., Alloiococcus otitis, Erysipelothrix rhusiopathiae, Staphylococcus caprae, Staphylococcus lentus, and gram-negative bacteria, e.g., Acinetobacter baumannii complex, Aeromonas salmonicida, Brucella melitensis, Oligella ureolytica were used whether a plastic kit to release ClO₂ gas could inhibit their growth. Overall, chlorine dioxide gas showed about 99% inhibition of bacterial growth, with less than 10 CFU. However, it was found that Gram positive Alloiococcus otitis and Gram negative Aeromonas salmonicida had more than about 50 CFU. When comparing the results of experiments with several bacteria, it suggested that the concentration of chlorine dioxide gas would be at least 10 ppm to 400 ppm for the bacterial inhibition. The results of this study could be used as basic data to evaluate the clinical usefulness of chlorine dioxide gas. If this study helps with prior knowledge to help clinicians to recognize and prevent the presence of micro-organisms that cause infections in hospitals, it would be helpful for activities such as patient care as a convergence field. In the future, it is considered that the research results will be the basis for rapidly inhibiting the microbes infected with patients by utilizing data of the information of the microbes that are inhibited for chlorine dioxide gas.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.49-57
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• 1999

In CLO2 delignification and bleaching process, formation of chlorate corresponds to a loss of 20-36% of the original CKO2 charge. Because chlorate is inactive and harmful to environmental, it will be of benefit to find methods that can reduce the formation of chlorate during chlorine dioxide bleaching. Chlorate is mainly formed by the reaction HCIO +ClO2 $\longrightarrow$H+ + Cl_ +ClO3-2 On the other hand, AOX in chlorine dioxide bleacing is formed also due to the in-situ produced hypochlorous acid. THus both AOX and chlorate could be reduced by addition of hypochlorous acid. Some paper son the reduction of AOX by additives appeared , but systematic data on chlorate reduction as well as pulp and effluent properties are not available. THus this paper of focused on the effects on the reduction of chlorate and chlorine dioxide bleachability. The additives, fulfamic a챵, AMSO, hydrogen peroxide, oxalic acid were found to eliminate chlorine selectively in chlorine and chlorine dioxide mixture.However, when they were added to bleaching process, sulfamic acid and DMSO showed significant reduction of chlorate formation but hydrogen peroxide and oxalic aicd did not, and significant amount ofhydrogen peroxide was found resided in the bleaching effluent , In addition, sulfamic acid and DMSO decreased the bleaching end ph values while hydrogen peroxide and oxalic acid did not, which also indicated that hydrogen peroxide and oxalic acid were ineffective. The difference might be ascribed to the competitives of hypochlorous acid with lignin, chlorite (CKO2) and additives. Sulfamic acid and DMSO showed better pulpbrightness development but less alkaline extraction efficiency than hydrogen peroxide , oxalic acid and control, which means that insitu hypochlorous acid contributes to the formation of new chromophore structures that can be easily eliminated by alkaline extraction. DMSO decreased the delignification ability of chlorine dioxide due to the elimination of hypochlorous acid, but sfulfamic acid did to because the chlroinated sulfamic acid had stable bleachability. In addition, sulfamic acid, and SMSO shwed decreased color and COD of bleaching effluents, hydrogen peroxide decreased effluent color but not COD content, and oxalic acid had no statistically significant effects. No significant decreases of pulp viocosity were found except for hydrogen peroxide. Based on our results , we suggest that the effectiveness of hydrogen peroxide on the reduction of AOX in literature might be explained by other mechanisms not due to the elimination of hypochlorous acid , but to the direct decomposition of AOX by hydrogen peroxide.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.308-312
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• 2018

Even though chlorine dioxide ($ClO_2$) is utilized in a pre-treatment due to its effective sterilizing activity for microorganisms and its safety for food, it has a limitation in maintaining freshness of the food product. In this study, a low-concentration $ClO_2$ gas was produced in a packaging form of air-permeable gel pack so that it could be released continuously over several days. The amount of $ClO_2$ gas emission and microbial inactivation effect against foodborne pathogens were measured during the release of $ClO_2$ gas. As a result of measuring the change of color in order to confirm whether the chlorine dioxide gas was eluted in the form of a sustained release, the yellowness was significantly higher at higher gel pack concentration and higher value during storage periods. The slow-released $ClO_2$ gel-pack showed clear inactivation effect against Escherichia coli and Staphylococcus aureus with 99.9% inactivation efficiency. As a result of measuring the sterilization effect of Listeria monocytogenes by the concentration of chlorine dioxide gas, the sterilization effect was increased as the concentration was increased. Therefore, the slow-released $ClO_2$ gel-pack is feasible to apply for industry usages.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.878-882
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• 2008

The efficacy of citric acid-aqueous chlorine dioxide ($ClO_2$) treatment of radish seeds artificially contaminated with Escherichia coli was studied. Radish seeds were inoculated with E. coli. Following inoculation, samples were stored at $4^{\circ}C$ and soaked in citric acid or aqueous $ClO_2$ for 10 min. The treatment of radish seeds using 200 ppm aqueous $ClO_2$ solution caused a 1.5 log CFU/g reduction in the population of E. coli. Compared to the aqueous $ClO_2$ treatment, soaking radish seeds in 2.0% citric acid solution for 10 min was more effective in reducing E. coli populations on radish seeds. The efficacy of spray application of chlorine (100 ppm) or 0.5% citric acid to eliminate E. coli during the germination and growth of radish was investigated. Radish seed inoculated with E. coli was treated for the duration of the growth period. Although it resulted in a decrease in the E. coli population, the spray application of 100 ppm chlorine during the growth period was not significantly effective. In contrast, the combined treatment of seeds using 200 ppm aqueous $ClO_2$ and treatment of sprouts with 0.5% citric acid solution during sprout growth was hardly effective in eliminating E. coli.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.451-455
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• 2020

This study evaluated acute toxicity of chlorine dioxide (ClO₂ ) to juveniles of black seabream Acanthopagrus schlegelii (19.4±2.3 g, 10.7±0.4 cm) and red seabream Pagrus major (74.9±8.2 g, 15.9±1.0 cm). Thirty juveniles for each species were exposed to target ClO₂ concentrations of 0, 0.05, 0.1, 0.125, 0.15, 0.2, 0.3, 0.4, and 0.5 mg/L in triplicate for eight days. Half lethal concentrations for 96 hours were found at 0.14 and 0.24 mg ClO₂/L for black seabream and red seabream, respectively. Red seabream larger than black seabream in body weight appears to be more resistance to chlorine dioxide. However, regardless of species or size, specific loading rates of chlorine dioxide to total fish weight (daily feeding amount of ClO₂/total fish weight) were similar, showing 1.3 and 1.1 g ClO₂/kg fish·day^-1 for black seabream and red seabream.

• Research in Plant Disease
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• v.27 no.4
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• pp.149-154
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• 2021

Pseudoperonospora cubensis (downy mildew) is highly virulent to various Cucurbitaceae crops, including cucumber (Cucumis sativus). We tested chlorine dioxide application in a plastic greenhouse for environment-friendly control of downy mildew disease. Spraying diluted chlorine dioxide suppressed downy mildew disease with 41.2% control efficacy. Thermal fogging with chlorine dioxide had a high control efficacy of 80.9%, confirming that this approach is useful for environment-friendly downy mildew control. Using thermal fogging to control diseases that are greatly affected by humidity, such as downy mildew, may be more effective compared with conventional dilution spray control methods.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.3
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• pp.61-69
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• 1987

In water treatment, prechlorination is often carried out to solve the troubles caused by Algae, but produces by-products that are known to be harmfull to human health. In this study, chlorine and chlorine dioxide used for algae removal process were compared in producing trihalomethanes and haloacetonitriles to study the possibilities in using chlorine dioxide as a alternative for chlorine. The raw water used for the study had 10,790 algae cells per one milliliter and Ankistrodesmus sp. were the most common.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.1
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• pp.17-27
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• 2013

The effects of chlorine dioxide gas ($ClO_2$) treatments between high-concentration-short-time and low-concentration-long-time on maintaining the quality of cherry tomatoes (Lycopersicon esculentum Mill. cv 'unicorn') were investigated. Tomatoes were treated with 5 ppm for 10 min and 10 ppm for 3 min as high-concentration-short-time $ClO_2$ gas treatment conditions and 1 ppm for once a day interval in terms of low-concentration-long-time $ClO_2$ gas treatment condition, respectively. After $ClO_2$ gas treatments, tomatoes were storage at 5 and $23^{\circ}C$ for 7 days. Weight loss, changes in tomato color, firmness, soluble solids content, pH, growth of total microorganism, and decay rate were evaluated. On day 7, tomatoes treated with chlorine dioxide gas showed low values of respiratory rate, total microbial growth, and decay rate compared to those of tomato without chlorine dioxide gas treatment. Additionally, tomatoes treated the chlorine dioxide were kept the values of firmness and soluble solids content during storage. However, chlorine dioxide gas treatment on tomatoes had no direct effect on weight loss, pH, and color. Results showed that both $ClO_2$ concentration and treatment time played the important roles for keeping the quality of tomatoes during storage. Tomatoes with chlorine dioxide gas treatment of low-concentration-long-time had more effective values of firmness, the total microbial growth, and decay rate than those with two chlorine dioxide gas treatments of high-concentration-short-time. Results suggest the potential use of chlorine dioxide gas treatment of low-concentration-long-time as an highly effective method for keeping the freshness of cherry tomato.

• Food Quality and Culture
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• v.3 no.1
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• pp.34-39
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• 2009

This study assessed the efficacy of aqueous chlorine dioxide ($ClO_2$) and commercial chlorine sanitizer in terms of its ability to eliminate Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7 on radish sprouts (Raphanus sativus L.). Radish sprouts were inoculated with a cocktail containing one each of three strains of three different foodborne pathogens, then treated with distilled water (control) or chemical sanitizers (100 ppm commercial chlorine, and 50, 100, 200 ppm $C1O_2$) for 1, 5, and 10 min at room temperature ($22{\pm}2^{\circ}C$). Populations of S. Typhimurium, E. coli O157:H7 and L. monocytogenes were counted at 4.64, 6.05, and 4.29 log CFU/g, respectively, after inoculation. Treatment with water did not significantly reduce the levels of any of the three foodborne pathogens. The levels of all three pathogens were reduced by treatment with chemical sanitizers; however, the observed levels of reduction of E. coli O157:H7 and L. monocytogenes were not significant as compared with the controls. The levels of the three pathogens were reduced most profoundly when treated for 10 min with 200 ppm of $C1O_2$, and the reduction levels of S. Typhimurium, E. coli O157:H7, and L. monocytogenes were 1.17, 1.63, and 0.96 log CFU/g, respectively. When chemically injured cells were investigated using SPRAB for E. coli O157 :H7 and by selective overlay methods for S. Typhimurium and L. monocytogenes, respectively, it was noted that commercial chlorine sanitizer generated more numbers of injured pathogens than did $C1O_2$. These data indicate that $C1O_2$ treatment may prove useful in reducing the numbers of pathogenic bacteria in radish sprouts.