• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.844-849
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• 2005

Bacteriocidal effect of calcium oxide (CaO, scallop shell powder) on reduction of microorganism in sesame leaf was evaluated through comparison with chemical sanitizers such as chlorine, ethanol, and hydrogen peroxide. CaO showed 0.55-1.49, 0.85-2.56, 0.16-1.08, 0.30-1.14, and $0.19-1.07\;log_{10}$ CFU/g reductions of total aerobic bacteria, total coliforms, Escherichia coli, Listeria monocytogenes, and Salmonella typhimurium respectively, indicating possible use of CaO as effective natural sanitizer.

• Korean Journal of Veterinary Service
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• v.20 no.2
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• pp.169-175
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• 1997

This study was carried out to assess the effect of the chlorine treatment into water for processing chicken products in each stage of slaughtering, with a special viewpoint related with reducing the viable number of microorganisms by which the water and the chicken body were contaminated. The mean bacterial number on chicken samples after picking process was log5.37$\pm$0.20~5.84$\pm$0.160CFU/$\textrm{cm}^2$. When assessed by standard plate count method, it was the higher one than any other processing stage in which eviscerating, pinning, packaging, and chilling was followed in order of the mean bacterial number. The coliform bacterial numbers on carcasses after sampling from different processing stages were log2.11$\pm$0.63~2.88$\pm$0.25MPN/$\textrm{cm}^2, which show almost similar numbers in each processing stage. But, after chilling process the number was decreased slightly. The bacterial counts in the water for scalding and chilling showed log3.43 $\pm$ 0.59~5.06$\pm$0.21 and log4.30$\pm$0.21~6.62$\pm$0.33CFU/$m\ell$, respectively. In the coliform counts for the water taken out from the 2nd chilling tank, the number was log1.97$\pm$0.35~2.91$\pm$0.22MPN/$m\ell$ which showed higher than those of the 1st and the 3rd chilling tank water. The effect of chlorination in reducing the bacterial numbers was accepted at the residual chlorine concentration of 1$m\ell$/$\ell$by showing the reduction from $10^8$ to $10^4$CFU level and the numbers were decreased less than 10CFU at the concentration of 5mg/$\ell$, when assessed by viable cell counts. In conclusion, these results suggested that chlorination In chilling water with final concentration of 5mg/$\ell$was strongly recommended to reduce the bacterial numbers on final chicken products.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.10a
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• pp.73-73
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• 2017

Pyroprocessing at KAERI (Korea Atomic Energy Research Institute) consists of pretreatment, electroreduction, electrorefining and electrowinning. SFR (Sodium Fast Reactor) fuel is prepared from the electrowinning process which is composed of LCC (Liquid Cadmium Process) and Cd distillation et al. LCC is an electrochemical process to obtain actinides from spent fuel. In order to recover actinides inert anodes such as carbon material are used, where chlorine gas ($Cl_2$) evolves on the surface of the carbon material. And, stainless steel (SUS) crucible should be installed in large-scale electrowinning system. Therefore, the effect of chlorine on the SUS material needs to be studied. LiCl-KCl-$UCl_3$-$NdCl_3$-$CeCl_3$-$LaCl_3$-$YCl_3$ salt was contained in 2 kinds of electrolytic crucible having an inner diameter of 5cm, made of an insulated alumina and an SUS, respectively. And, three kinds of electrodes such as cathode, anode, reference were used for the electrochemical experiments. Both solid tungsten (W) and LCC were used as cathodes. Cd of 45 g as the cathode material was contained in alumina crucibles for the deposition experiments, where the crucible has an inner diameter of 3 cm. Glassy carbon rod with the diameter of 0.3 cm was employed as an anode, where shroud was not used for the anode. A pyrex tube containing LiCl-KCl-1mol% AgCl and silver (Ag) wire having a diameter of 0.1cm was used as a reference electrode. Electrodeposition experiments were conducted at $500^{\circ}C$ at the current densities of $50{\sim}100mA/cm^2$. In conclusion, Fe ions were produced in the salt during the electrodeposition by the reaction of chlorine evolved from the anode and Fe of the SUS crucible and thereby LCC system using SUS crucible showed very low current efficiencies compared with the system using the insulated alumina crucible. Anode shroud needs to be installed around the glassy carbon not to influence surrounding SUS material.

• Analytical Science and Technology
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• v.35 no.6
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• pp.242-248
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• 2022

The effect of ethylenediamine (EDA) on the reaction of luminol or Bluestar with blood and bleaches was studied. For this purpose, blood, chlorine bleach, and oxygen bleach were applied to filter paper, treated with EDA-containing luminol or Bluestar, and the changes in chemiluminescence intensity were observed. It was found that the chemiluminescence intensity of the luminol (or Bluestar)-blood reaction did not change with the increasing concentration of EDA. However, the chemiluminescence intensity of the luminol (or Bluestar)-chlorine bleach reaction decreased and the chemiluminescence intensity of the luminol (or Bluestar)-oxygen bleach reaction increased, with increasing EDA concentration. Thus, it was found that when EDA was added to luminol (or Bluestar), which is a blood-sensitive reagent, EDA suppressed the false-positive reaction induced by chlorine bleach and induced a false-positive reaction with oxygen bleach. Consequently, the addition of EDA is not recommended for enhancing bloodstains with luminol or Bluestar.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.753-760
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• 2021

This study was carried out to discover suitable packaging methods during the cold or frozen storage of sawtooth oak and Japanese larch seedlings, which are major afforestation tree species in Korea. The weight loss rate of sawtooth oak was lower under frozen storage at -2℃ (maximum, 33.7%) than under cold storage at 2℃ (maximum, 61.0%). A film liner treatment inside the packaging box effectively suppressed the increase in the weight loss rate. For the sawtooth oak containerized seedlings, when stored at -2℃, the rate of weight loss was 17.9 to 25.4% in the untreated group and less than 1% in the film liner treatment group. Similar results were observed with Japanese larch. After two months of freezing at -2℃, both species maintained a low index of 1.0 - 1.1 with regard to the degree of shoot desiccation of containerized seedlings, and there was no significant difference between the treatments. On the other hand, the chlorine dioxide treatment could more effectively reduce the occurrence of mold and shoot desiccation than a PE single treatment in bare-root seedlings. According to these results, it was concluded that frozen storage is generally suitable as a means of long-term storage compared to cold storage of sawtooth oak and Japanese larch. A chlorine dioxide treatment at 20 ppm was effective for maintaining seedling quality levels during storage, demonstrating the good effect of suppressing the occurrence of shoot desiccation and the occurrence of mold.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.37-42
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• 2004

ECF and TCF bleaching methods are favored in bleaching plants over the world due to the increasing environment constraints. However, interaction of main stages(D and O stage) in ECF bleaching have not been understood completely yet. The degradation of holocellulose as a carbohydrate model compound was investigated by SEC(size exclusive chromatography) to estimate the change of its molecular weight distribution after O and D stage combination treatment. The molecular weight distribution of holocellulose was observed in two divisions(higher and lower molecular portions). It was also shown that DO sequence was more effective than OD, and DOD or ODO was more effective than DO. D stage had a little effect on the degradation of holocellulose, while the degradation of holocellulose increased as the time of the first O stage increased.

• Journal of Environmental Science International
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• v.11 no.5
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• pp.411-418
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• 2002

The current study evaluated the disinfection efficiency of free chlorine and chloramine for microorganisms on various pipe materials, such as copper, galvanized steel, carbon steel, and stainless steel. In addition, the effect of internal pipe corrosion and corrosion inhibitors on the bactericidal efficiency was evaluated using a simulated loop. For disinfection with a phosphate corrosion inhibitor, chloramination was found to be more effective than chlorination due to its persistence. Free chlorine disinfection was optimized with a high phosphoric acid concentration, while chloramine disinfection was optimized with a high phosphoric acid or low polyphosphate concentration. In simulated copper and galvanized steel loop tests, chloramination with phosphoric acid was demonstrated to be more effective.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.38-39
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• 2019

Mechanical properties of concrete containing furnace slag according to the CBS Dust Replacement Ratio were analyzed. The experimental study found that the compressive strength was excellent in the early age when the CBS Dust was replaced, and the drying shrinkage was excellent, and the replacement of CBS Dust 5% on the concrete containing the furnace slag would have a positive effect.

• Proceedings of the Korean Society of Crop Science Conference
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• 2018.10a
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• pp.284-284
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• 2018

• Journal of Environmental Science International
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• v.25 no.7
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• pp.905-916
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• 2016

The characteristics of phenol removal and $UV_{254}$ matters variance were investigated and compared by the variation of operating factors (NaCl concentration, air flow rate, initial phenol concentration) in electrochemical reaction (ER) and dielectric barrier discharge plasma reaction (DBDPR), respectively. The phenol removal rate was shown as $1^{st}$ order both in ER and DBDPR. Also, the absorbance of $UV_{254}$ matters which means aromatic intermediates was analyzed to investigate the complete phenol degradation process. In ER, the phenol degradation and aromatic intermediates production rates increased by the increase of NaCl concentration. However, in DBDPR, the variation of NaCl concentration had no effect on the degradation of phenol and $UV_{254}$ matters. Air flow rate had a little effect on the removal of phenol and the variation of $UV_{254}$ matters in ER. The phenol removal rate in ER was a little higher than that in DBDPR. The produced $H_2O_2$ and $O_3$ amounts in ER were 2 times and 10 times higher than those in DBDPR. The chlorine intermediates ($ClO_2$ and free chlorine) were produced in ER, however, they were not produced in DBDPR.