• The Plant Pathology Journal
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• v.35 no.2
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• pp.156-163
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• 2019

Our study investigated the available chlorine content, contact time and difference among strains of each pathogen for sodium hypochlorite (NaOCl) to control chemically against soil-borne fungal pathogens, such as Phytophthora rot by Phytophthora cactorum, violet root rot by Helicobasidium mompa, and white root rot by Rosellinia necatrix, causing die-back symptom on apple trees. As a result, the colony growth of Phytophthora cactorum was inhibited completely by soaking over 5 s in 31.25 ml/l available chlorine content of NaOCl. Those of H. mompa and R. necatrix were inhibited entirely by soaking over 160 s in 62.5 and 125 ml/l available chlorine content in NaOCl, respectively. Also, inhibition effect on available chlorine in NaOCl among strains of each soil-borne pathogen showed no significant difference and was similar to or better than that of fungicides.

• The Plant Pathology Journal
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• v.38 no.5
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• pp.513-521
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• 2022

Our study was carried out to determine the control efficacy of sodium hypochlorite (NaOCl) for violet root rot caused by Helicobasidium mompa in apple. The experiment was conducted in the farm located at Chungbuk province in South Korea from 2014 to 2016. When infected apple trees were treated at least two or three times with 31.25 and 62.5 ml/l available chlorine content in NaOCl, it greatly increased the rooting of rootstock, and restored the tree crown density by 44.4-60.5%. In addition, the number of commercial fruit setting was increased by 54.3-64.5%, and the total starch content in shoots was significantly higher than other non-treated apple trees. However, the untreated disease control and thiophanate-methyl WP treated trees showed the symptom of dieback. Therefore, our results indicate that the drenching treatment of NaOCl with 31.25-62.5 ml/l available chlorine content more than two times from late fall to early spring could effectively control the violet root rot and recover tree vigor up to 60%.

• Journal of the Mineralogical Society of Korea
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• v.26 no.1
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• pp.9-18
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• 2013

In order to optimize the gold leaching process from refractory sulfide concentrate, a chlorine-hypochlorite solution with varying concentrations and temperatures were applied to salt-roasted concentrate. The concentrate consisted of pyrite, chalcopyrite, and galena, which were turned into hematite through air-roasting at $750^{\circ}C$. Also these concentrates were changed into hematite and nantokite (CuCl)) through salt (NaCl)-roasting at $750^{\circ}C$. The results of the gold leaching experiments showed that the best gold leaching parameters were obtained when the hydrochloric acid-sodium hypochlorite mix was at a ratio of 1 : 2, the added concentration was 1.0 M concentration, the pulp density was 1.0%, and the leaching was done at a $60^{\circ}C$ leaching temperature. The leaching rate for gold was much greater in the roasted concentrate than in the raw concentrate. The leaching rate was greater in the salt-roasted concentrate than in the plain roasted concentrate too. From XRD analysis, quartz was found in the salt-roasted concentrate and in the solid residue from the chlorine-hypochlorite leaching solution at $60^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.206-212
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• 1998

The effects of the pretreatment with coagulants on the recovery efficiency of poly (3-hydroxybutyrate, PHB) synthesized in Alcaligenes eutrophus were investigated. Al-base or Fe-base coagulants, and the dispersion method of 30% hypochlorite solution and chloroform were used as coagulants and PHB recovery method, respectively The recovery efficiency of PHB from the cells harvested with Al-base coagulants at the range from 0 to 1000 mg-Al/L was similar to that from cells harvested without the coagulants. At these conditions, the concentrations of residual aluminium in the purified PHB were below 250 mg-Al/kg-PHB, indicating the effect of residual aluminum on the characteristics of the purified PHB can be insignificant. When the dosage of coagulants was over 1000 mg-Al/L, the PHB recovery remarkably decreased with increasing the coagulant dosage. However, the PHB recovery could be enhanced by the use of 50% hypochlorite solution instead of 30% hypochlorite solution. Even though the reduction of PHB recovery efficiency was not found by using Fe-base coagulants, the purified PHB was stained pale red due to residual iron, These results suggest that the use of Al-base coagulants did not exert bad influence on neither PHB recovery efficiency and PHB purity.

• Economic and Environmental Geology
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• v.47 no.6
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• pp.645-655
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• 2014

In order to obtain pure metallic Te from gold concentrate, roasting treatment, hypochlorite leaching, Fe removal and electrolysis experiments were carried out. The contents of Au, Ag and Te from the concentrate sample and roasted sample were much more soluble in the hypochlorite solution than in aqua regia digestion, whereas the metals Pb, Zn, Fe and Cu were easier to leach with the aqua regia than the hypochlorite. With the addition of NaOH in the hypochlorite leaching solution prior to electrolysis, the Fe removal rate achieved was only 96% in the concentrate sample, while it reached 98% in the roasted sample. The results of electrolysis for 240 min, 98% of the metallic copper was recovered from the concentrate sample, while 99% was obtained from the roasted sample due to the removal of S by roasting. The amount of anode slime was also greater in the electrolytic solution with the roasted sample than with the concentrate sample. The results on the anode slime after the magnetic separation process showed the amount of metallic pure native tellurium recovered was greater in the roasted sample than in the concentrate sample.

• Korean Journal of Poultry Science
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• v.40 no.4
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• pp.327-336
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• 2013

This study was conducted to examine the effect of spray-washing old hens (old laying hens, old molting hens and old breeder hens) carcasses with sodium hypochlorite (50 ppm) solution and vacuum packaging on the microbiological and physiochemical quality of breast meat during storage at $4^{\circ}C$. There were no significant differences of cooking loss and texture among breast meats from different birds with spray-washing by water or sodium hypochlorite solution before storage. The numbers of total aerobic bacteria of aerobically packaged and only water-washed breast meat were higher than 7 Log CFU/g (the limitation population for spoilage of meat) after 7 days of storage. However, the numbers of total aerobic bacteria of vacuum packaged breast meat washed by sodium hypochlorite solution were lower than 7 Log CFU/g even after 14 days of storage. The volatile basic nitrogen content of vacuum packaged breast meat were lower than 20 mg% (the limitation value for spoilage of meat) regardless of the washing method, while those of aerobically packaged breast meat washed by tap water and sodium hypochlorite solution were 41.1 and 20.1 mg%, respectively. In addition, lipid oxidation and change of pH in breast meat was inhibited by vacuum packaging when compared with that of aerobic packaged breast meat during storage. Therefore, the results indicated that the washing old hen's carcasses with sodium hypochlorite (50 ppm) solution and vacuum packaging could improve the shelf-life of meat from old birds. This result can provide the basic information for industry, which are seeking for export market.

• Restorative Dentistry and Endodontics
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• v.37 no.3
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• pp.185-186
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• 2012

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.726-728
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• 1998

• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.924-926
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• 1994

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.430-433
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• 2000

The disinfection effects of Trichloro isocyanuric acid (TICA) and Calcium hypochlorite (Cal-hypo) against E. coli' in aqueous suspension were compared at various concentrations of disinfectants as well as exposure times. When E, coil($^{\sim}10^7$ CFU/ml) were exposed by TICA and Cal-hypo (12 ppm each), 90% of the initial cells were reduced in 4 sec and 390 sec, respectively. Although Cal-hypo lost its disinfection capability in about 1 hr under the sun light, TICA maintained its effect up to 6 hrs. This comparative studies clearly demonstrate that TICA is more effective than Cal-hypo in terms of sterilizing E. coli as well as maintaining the disinfection effects.