• Journal of the Korean Applied Science and Technology
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• v.23 no.1
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• pp.77-84
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• 2006

Modified polyesters (TTBA-10C, -20C, -30C) that contain phosphorus and chlorine were synthesized by the condensation polymerization of tetramethylene bis(orthophosphate), neohexanediol trichlorobenzoate, 1,4-butanediol and adipic acid, in which tetramethylene bis(orthophosphate) and neohexanediol trichlorobenzoate were prepared previously in our laboratory. In this study, two-component flame-retardant polyurethane coatings (TTBA-10C/HDI-trimer=TTHD-10C, TTBA-20C/ HDI-trimer= TTHD-20C, TTBA-30C/HDI-trimer= TTHD-30C) were obtained by curing at room temperature with the synthesized TTBAs and hexamethylene diisocyanate (HDI)-trimer as a curing agent. The obtained TTHDs were made into coating samples and used as test samples for various physical properties. The physical properties of the flame-retardant coatings containing chlorine and phosphorus groups were generally inferior to those containing only phosphorus group. Flame retardancy was tested by vertical and horizontal combustion method, and $45_{\circ}$ Meckel burner method. Since the retardancy of flame-retardant coatings containing chlorine and phosphorus groups was better than that containing only phosphorus group, it could be concluded that the retardancy by the synergism effect of chlorine and phosphorus groups exhibited.

• Journal of The Korean Society of Integrative Medicine
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• v.4 no.4
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• pp.109-117
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• 2016

Purpose : This study was designed to provide basic data of effective sanitization method of sprout vegetable for microbiological safety. Methods : Sanitization treatments were performed by dipping the sprout into chlorine and vinegar water. Microbial analysis were composed of the total plate count(TPC) and coliform group count(CGC). Result : Among chlorine water sanitization, the microbial reduction was largest in 100ppm chlorine water, and its TPC and coliform group count decreased to 6.01 log CFU/g and 5.06 log CFU/g. The effective dipping time in 100ppm chlorine water treatment was 5.97 log CFU/g and 5.91 log CFU/g for 30min and 60min, in which TPC were below the microbiological safety limits of 6.00 log CFU/g. Coliform group counts were decreased to 5.44, 5.46, 5.42 log CFU/g in the dipping the spouts for 30min, 60min and 90min. As a result of sanitizing alfalfa spout by vinegar water, a microbial counts tended to decrease with increasing concentration and the dipping time. The effective concentration of vinegar water was 2% for TPC(6.00 log CFU/g) and 1% for coliform group count(5.20 log CFU/g). With 1% vinegar water treatment, TPC became below the microbiological safety limits in all samples and in particular, the sample treated for 60min and 90min(4.93, 4.54 log CFU/g). While coliform group counts were decreased to 3.91 log CFU/g in the dipping the sprouts for 90min, those were still beyond the permitted limit. Conclusion : To secure the food safety of food service facilities including kindergarten feeding, it is considered that along with the systematic study of effective disinfection method for microbiological control at the preconditioning level of spout vegetable within the range of secured maleficence to human body, and the study regarding the measures to lower the initial microbiological pollution of spout vegetable.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.5
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• pp.397-407
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• 2017

A dimensionally stable anode based on the $RuO_2$ electrocatalyst is an important electrode for generating chlorine. The $RuO_2$ is well-known as an electrode material with high electrocatalytic performance and stability. In this study, sonoelectrodeposition is proposed to synthesize the $RuO_2$ electrodes. The electrode obtained by this novel process shows better electrocatalytic properties and stability for generating chlorine compared to the conventional one. The high roughness and outer surface area of the $RuO_2$ electrode from a new fabrication process leads to increase in the chlorine generation rate. This enhanced performance is attributed to the accelerated mass transport rate of the chloride ions from electrolyte to electrode surface. In addition, the electrode with sonodeposition method showed higher stability than the conventional one, which might be explained by the mass coverage enhancement. The effect of sonodeposition time was also investigated, and the electrode with longer deposition time showed higher electrocatalytic performance and stability.

• Journal of Environmental Health Sciences
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• v.8 no.2
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• pp.33-46
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• 1982

This experiment was carried out for the purpose of reducing alkaloid in reconstituted tobacco sheet and effluent of reconstituted tobacco sheet manufacturing company by treating oxidizing agents such as ozone, sodium hypochlorite, perchloric acid and hydrogen peroxide to tobacco extract created from the manufacturing process of reconstituted tobacco sheet. The effect of alkaloid reduction in tobacco extract by the volume added, time of treatment and pH of oxidizing agents were as follows: 1. When the solid rate of tobacco extract stood at 10 percent, the content of alkaloid, total sugar, total nitrogen and chlorine was 1,600mg/l, 11,000mg/l, 3,200mg/l and 4,000mg/l, respectively. 2. The effect of alkaloid reduction through ozone treatment was in proportion to time of ozone treatment. Alkaloid showed a 31.2 percent reduction under 8 hours' ozone treatment and 0.23g ozone consumed to remove lmg alkaloid. 3. Alkaloid reduction through sodium hypochlorite treatment was influenced by quantity of chlorine in sodium hypochlorite solution. To remove lmg alkaloid, 36.3mg chlorine was used. Reduction of alkaloid was not affected by time of sodium hypochlorite treatment, while showed the best reaction under pH 5-7. 4. The effect of alkaloid reduction by perchloric acid was under the control of the volume added and time of treatment of perchloric acid. The volume of perchloric acid required to remove alkaloid was on the decrease as time of treatment was getting longer. lmg alkaloid was removed by 0.15g perchloric acid under 8 hours' perchloric acid treatment. 5. Alkaloid reduction reacted slowly to the volume added and time of treatment of hydrogen peroxide. Under 8 hours' hydrogen peroxide treatment, it showed maximum removal, registering 10 percent alkaloid reduction.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.487-497
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• 2018

Controlling of microorganisms in the industrial process is important for production and distribution of hatching and table eggs. In the previous study, we reported that chlorine dioxide ($ClO_2$) gas of a proper concentration and humidity can significantly reduce the load of Salmonella spp. on eggshells. In this study, we compared microbial reduction efficacy on egg's surface using hatching eggs and table eggs, internal quality of table eggs, and hatchability after both the conventional method (washing and UV expose, fumigation with formalin) and $ClO_2$ gas disinfection. Application of 40 ppm $ClO_2$ gas to the table and hatching eggs, respectively, reduced the aerobic plate count (APC) with no statistical difference compared with the conventional methods. Additionally, we didn't observed that any significant difference in albumin height, Haugh unit (HU), and yolk color, this result confirms that 40 ppm $ClO_2$ had no effect on the internal quality of the table eggs, when comparing with the UV treatment method. The hatchability of hatching eggs was not statistical different between formaldehyde fumigation and 80 ppm $ClO_2$ gas treatment, though the value was decreased at high concentration of 160 ppm $ClO_2$ gas. From these results, we recommend that $ClO_2$ gas can be used as a safe disinfectant to effectively control egg surface microorganisms without affecting egg quality.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.4
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• pp.43-47
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• 2000

The etching characteristic of a tantalum thin film with pure chlorine plasma was studied using an electron cyclotron resonance etcher system. Optical emission actinometry (OEA) was used for the study of the etching mechanism of a tantalum thin film and optimum process condition was achieved by OEA study. Based on this mechanism, double step etching was performed and 0.15 $\mu\textrm{m}$ L & S was acquired successfully suppressing the microloading effect.

• Transactions on Electrical and Electronic Materials
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• v.1 no.2
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• pp.1-6
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• 2000

This article presents the experiments and considerations possible about gate etching in polysilicon when oxygen gas is added in chamber, We propose the novel study with optical emission spectroscopy in polysilicon etching. It is shown that added oxygen gases play an important role in enhencement of density in chlorine gases as a scavenger of silicon from SiCl$\_$x/. And a small amount of Si-O bonds are deposited and then the deposited thin film protect silicon dioxyde against reaction chlorine with silicon in SiO$_2$. Consequently, we can improve the selectivity of polysilicon the silicon dioxide, which is clearly explained in this model.

• Resources Recycling
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• v.30 no.5
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• pp.10-16
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• 2021

In this study, a clinker was prepared using raw materials with CaCl₂. The characteristics of the chlorine-added clinker and cement were analyzed. The clinker modulus were set to Lime Saturation Factor (LSF) 92, Silica modulus (SM) 2.5, and Iron Modulus (IM) 1.5. The physical properties of cement using the chlorine-containing clinker were characterized. As the chlorine content increased, the free-CaO content in the clinker decreased, and that in the 2000 ppm clinker was reduced by approximately 40% compared to that in the 0 ppm clinker. There was an increase in the amount of chlormayenite, with a content of up to 3.4% present in the 2000 ppm clinker. The amounts of alite and belite also slightly increased. The compressive strength of mortar at 3 days and 7 days increased as the chlorine content increased. This trend was presumed to arise from the effect of hydration, which was promoted by the presence of chlorine. The compressive strength of 1000 ppm mortar increased by approximately 20% compared to that of 0 ppm mortar.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.891-898
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• 2011

The aim of this research was to evaluate the effect of combination of disinfection process (electrolysis, UV process) on Escherichia coli (E. coli) disinfection and oxidants (OH radical, $ClO_2$, HOCl, $H_2O_2$ and $O_3$) generation. The effect of electrolyte type (NaCl, KCl and $Na_2SO_4$) on the E. coli disinfection and oxidants generation were evaluated. The experimental results showed that performance of E. coli disinfection of electrolysis and UV single process was similar. Combination of electrolysis and UV process enhanced the E. coli disinfection and 4-carboxybenzaldehyde (4-CBA, indicator of the generation of OH radical) degradation. It is clearly showed synergy effect on disinfection and OH radical formation. However chlorine ($ClO_2$, HOCl) and oxygen type ($H_2O_2$, $O_3$) oxidants were decreased with the combination of two process. In electrolysis + UV complex process, electro-generated $H_2O_2$ and $O_3$ were reacted with UV light of UV-C lamp and increased 4-CBA degradation(increase OH radical). Disinfection of electrolyte of chlorine type was higher than that of the sulfate type electrolyte due to the higher generation of OH radical and oxidants.

• 수도
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• s.62
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• pp.69-79
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• 1993