• Journal of Soil and Groundwater Environment
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• v.14 no.1
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• pp.78-82
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• 2009

In this study, the feasibility of soil washing and soil flushing was investigated to treat Zn-contaminated railroad soil. Various organic acids including ethylene diamine tetraacetic acid (EDTA) and citric acid as well as inorganic acids such as hydrochloric acid (HCl) and phosphoric acid were tested to evaluate washing efficiency. Generally, inorganic acid showed higher removal efficiency compared to organic acids. Particularly, EDTA, well known as the most effective washing agent for removal of heavy metals from soil, was not efficient to remove zinc in this study. Among washing agents tested in this study, HCl was the most effective. However, it is not effective to use HCl solution over 0.1 M concentration. Sequential process using HCl was effective to enhance the removal efficiency of zinc. In column test, the removal efficiency of Zn was 27%. Accordingly, it is feasible to treat Zn-contaminated railroad soil using soil washing or flushing with HCI.

• Macromolecular Research
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• v.14 no.2
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• pp.194-198
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• 2006

Polystyrene, PS, particles of 450 nm diameter and poly(styrene-co-styrene sulfonate), PSS, particles of 140-160 nm diameter were prepared by emulsifier-free emulsion polymerization. The surfaces of the PS and PSS particles were coated with Ag nanoparticles for the application of antimicrobial agents by reduction of Ag ions using ${\gamma}$-irradiation. The Ag-PS and Ag-PSS were characterized by High-Resolution Transmittance Electron Microscopy (HR-TEM), Field-Emission Scanning Electron Microscopy (FE-SEM), and Energy Dispersive X-ray Spectroscopy (EDXS). The HR-TEM and EDXS data showed that the Ag nanoparticles were loaded on the surface of the PS and PSS particles, respectively. The antimicrobial efficiency of the Ag-PS and Ag-PSS particles (0.4 g) with ca. 100 ppm Ag, which was coated onto yam (KS K 0905-1996 rule), was tested against Staphylococcus aureus ATCC 6538 and Klebsiella pneumoniae ATCC 4352 after 100 washing cycles (KS K 0432-1999 rule). The antimicrobial efficiency of the Ag-PS particles against Staphylococcus aureus ATCC 6538 and Klebsiella pneumoniae ATCC 4352 was 99.9% after 100 cycles washing., confirming that the Ag-PS particles can be used as antimicrobial agents.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1236-1241
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• 2007

The feasibility of soil washing was investigated in the laboratory to treat heavy metals-contaminated railway soil. Various organic acids including ethylene diamine tetraacetic acid (EDTA) and citric acid as well as inorganic acids such as hydrochloric acid (HCl) and phosphoric acid were tested to evaluate washing efficiency. Generally, inorganic acid showed higher removal efficiency compared to organic acids. Specially, EDTA, which are well known as most effective washing agent to remove heavy metals from soil, was not efficient to remove heavy metals in this study. Among washing agents tested in this study, HCl was most effective. The removal of Cd, Cu, and Pb was high, however, that for Zn and Ni was less than 30% with 0.5 M HCl. This difference comes from analytical methods (Korean Standard Test Method for Soil). Aqua regia was used to extract Zn and Ni, however 0.1 N HCl was used for other metals. As a result, simple washing technology is not effective, to treat railway contaminated soil with heavy metals.

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.241-250
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• 2012

Objectives: This study was performed to investigate hygienic behavior of food handlers and general population focusing on awareness of hand-washing and the microbial load of their hands. Methods: A questionnaire survey and microbiological analysis were carried out for sixty-four people each. Samples for microbiological analysis were collected through the glove-juice method from the hands, and were analyzed for the presence of aerobic plate counts, total coliform, fecal coliform, Escherichia coli, Staphylococcus aureus, and Salmonella spp. according to the Food Code of Korea. Results: In the survey, significant differences between the food handlers and general population (p < 0.01) were found in hand-washing frequency, duration, use of hand-washing agents, washing parts of hands, hand-drying method, and method of turning off water. In eight different situations among the ten particular situations in their daily life, more food handlers responded to wash their hands than general population (p < 0.05). Bacterial load on hands with general population was consistently higher than with food handlers (p < 0.05), however, percentages of positive hands of S. aureus and Salmonella spp. were not. Conclusions: Poor hand hygiene practices were indicated by the positive results for E. coli, S. aureus, and Salmonella spp. on the hands of some respondents in both groups. This study reveals that there is the need for programs or campaigns to increase hand-washing practices of both groups.

• Journal of Soil and Groundwater Environment
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• v.15 no.2
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• pp.47-54
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• 2010

Although the demands for the dredging work have been increasing due to social and industrial reasons including national plan for restoration of four major rivers, environmental standards or management guidelines for the dredged river sediment are limited. The suggested environmental standard for the beneficial use of dredged river sediment consists of two levels, recyclable and concern, and includes eight contaminants such as metals and organic contaminants. The systematic approach to remediate dredged river sediment is also suggested. The system consists of both washing and stabilization processes with continuous multi particle separation. In the early stage, the sediments are separated into two particle sizes. The coarse-grained sediment over 0.075 mm, generally decontaminated with less trouble, follows normal washing steps and is sent for recycling. The fine-grained sediments under 0.075 mm are separated again at 0.025 mm. The particles bigger than this second separation point are treated in two ways, advanced washing for highly contaminated sediments and stabilization for less. The lab test results show that birnessite and apatite are most effective stabilizing agents among tested for Cd and Pb. The most fine residues, down-sized by continuous particle separation, are finally sent for disposal. The system is tested for metals in this study, but is expected to be effective for organic contaminants included in the environmental standard, such as PAH and PCE. The feasibility test on the field site will be followed.

• Journal of Environmental Health Sciences
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• v.40 no.3
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• pp.245-254
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• 2014

Objectives: This study was performed to investigate hand washing awareness of females and load of indicator bacteria on their hands. This study focused on the variation according to their age. Methods: A self-administered questionnaire survey and bacterial analysis of indicator bacteria were carried out for 100 Korean women in their age from 20 s to 60 s. Hand samples were collected through a modified glovejuice method. Results: In the survey, significant difference (p < 0.05) was found among the age groups in the use of hand washing agents. The levels of aerobic colony count (ACC) were the highest in both hands among the 20s (p < 0.05). The levels of Escherichia coli were higher in both hands in their 20s and 30s. No significant difference was found in the levels of Staphylococcus aureus and Salmonella spp. However, the positive rates of S. aureus (left hand, 37.5~47.1%; right hand, 58.5~62.5%) and Salmonella spp. (left hand, 25.0~52.9%; right hand, 37.5~64.7%) were higher in the hands of the 20s and 30s, and then showed decreasing trend according to increase of age. The effect of hand washing frequency on the ACC level of hands was significant (p < 0.001). Conclusions: These results indicate that there was no remarkable difference of hand hygiene awareness among female age groups. The detection of S. aureus and Salmonella spp. on the hands of some females in each age group revealed poor hand hygiene practices. The significant effect of hand washing frequency on the ACC level suggests that frequent hand washing is helpful to reduce hand contamination.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.57-62
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• 2006

Six organophosphorus, one organochlorine, and three synthetic pyrethroid pesticides were analyzed for their residues during washing and hot-air drying of red peppers conducted in the production of powder. The residue ratio in organophosphorus pesticides was 33% in chlorpyrifos, 31 % in diazinon, 50% in methidathion, 80% in EPN, 28% in fenitrothion, and 60% in profenofos. The ratio in pyrethroids was 109% in cypermethrin, 102% in deltamethrin, and 106% in fenvalerate. That in organochlorine was 56% in ${\alpha}$-endosulfan and 90% in ${\beta}$-endosulfan. The results were greatly different between organophosphorus and pyrethroid pesticides. UV irradiation along with hot-air drying brought about a remarkable reduction of the residues, up to 70% as compared with hot-air drying only. The removal effect was most remarkable in pyrethroids, which are hardly removed by hot-air drying. The color of the pepper was not changed during UV irradiation. The use of oxidizing agents such as hydrogen peroxide or chlorine dioxide during washing did not show a remarkable removal of residues. The residue ratio was not affected whether the pesticide is contaminated artificially or naturally.

• Textile Coloration and Finishing
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• v.23 no.4
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• pp.257-262
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• 2011

The dish cloth requires antimicrobial activity for hygienic purpose. Until now, organic antimicrobial agents of low cost have been frequently used for the anitimicrobial finishing. However, a cleaner hving anitimicroial activity should be more durable considering consumers' ever-increasing expectation. In this study, the cleaner containing the bamboo fiber were finished with a formulation of a new zirconium-containing inorganic agent of zirconium phosphate and polyurethane binders. The optimum treatment condition was investigated. And its durability against repeated laundering cycles was assessed. The existence of Zr after the repeated laundering was verified and the antimicrobial effect did not decrease under 30 washing cycles.

• Journal of the Korea Fashion and Costume Design Association
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• v.4 no.1
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• pp.99-110
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• 2002

This study is performed to investigate the effect of the mordant and chitosan on the colorfastness to laundering and physical properties of the mordanted, chitosan treated and natural - dyed cotton, silk and acrylics substrates. Natural dyes are extracted from Gromwell by boiled water. Three different compounds of Al, Cu, Sn and Chitosan are used as mordanting agents. The result of this study is summarized as follows: 1. Color of the fabrics dyed with Gromwell changes redder, bluer and darker after chitosan treated and mordanting. 2. After washing, the color of natural dyes changes more light and gray, Chitosan and Cu mordanting gives better colorfastness in washing than any others. 3. All chitosan treated fabrics improve air permeability. 4. In the chitosan treated fabrics, a half life of the static electricity is shown good result.

• Textile Coloration and Finishing
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• v.35 no.1
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• pp.1-7
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• 2023

In this study, the influence of pre-treatment(bleaching, mercerization by liquid ammonia and caustic soda) on cotton fabrics were investigated on dyeing Rubia cordifolia extracts. Aluminium Sulfate, Iron(Ⅱ) Sulfate Heptahydrate, Copper(Ⅱ) Sulfate Pentahydrate, Tin(Ⅱ) Sulfate, Manganese(Ⅱ) Chloride Tetrahydrate were used as mordanting agents. K/S value and washing fastnesses of the dyed cotton fabrics pretreated under different conditions were investigated. The K/S values were increased in the order of bleaching, liquid ammonia and mercerization pre-treatment. It was found that the pre-treatment conditions did not significantly affect the color change. The colorfastness to washing of most of all dyed fabrics were over grade 4 regardless of pre-treatment condition.