• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.39-49
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• 2021

The behaviors of various desorption agents were investigated during the desorption of cesium (Cs) from samples of clay minerals and actual soil. Results showed that polymeric cation exchange agents (polyethyleneimine (PEI)) efficiently desorbed Cs from expandable montmorillonite, whereas acidic desorption solutions containing HCl or PEI removed considerable Cs from hydrobiotite. However, most desorption agents could desorb only 54% of Cs from illite because of Cs's specific adsorption to selective adsorption sites. Cs desorption from an actual soil sample containing Cs-selective clay mineral illite (< 200 ㎛) and extracted from near South Korea's Kori Nuclear Power Plant was also investigated. Considerable adsorbed 137Cs was expected to be located at Cs-selective sites when the 137Cs loading was much lower than the sample's cation exchange capacity. At this low 137Cs loading, the total Cs amount desorbed by repeated washing varied by desorption agent in the order HCl > PEI > NH4+, and the highest Cs desorption amount achieved using HCl was 83%. Unlike other desorption agents with only cation exchange capabilities, HCl can attack minerals and induce dissolution of metallic elements. HCl's ability to both alter minerals and induce H+/Cs+ ion exchange is expected to promote Cs desorption from actual soil samples.

• Journal of the Korean GEO-environmental Society
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• v.14 no.11
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• pp.25-31
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• 2013

Civil and military firing ranges are usually contaminated with heavy metals such as lead and copper and remediation is required. Acid washing and extraction are common remediation methods. Lead contaminated firing range soil samples were collected and a preliminary study was conducted to evaluate the characteristics of the contamination and the contribution of high specific gravity particles. Ethylenediamine tetra acetic acid(EDTA) extraction was applied for the removal of heavy metal but the extraction was not feasible for the firing range soil. Even after the repeated EDTA extraction, the contamination were still over the Korean environmental standard indicating that soil particles highly contaminated with heavy metal which release the heavy metal ion even after the repeated extraction. Some colored and higher specific gravity particles were separated from the soil samples and analyzed. The colored particles have specific gravity of 2.5-6.6. The saturation ratio of Pb and EDTA was 4.9-32%. After removal of these colored particles, the sandy soil showed moderate contamination which can be treated with soil washing. This was proved with the five-level sequential extraction and TCLP tests.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1125-1130
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• 1997

The effects of enzyme combination, pH, acid washing and enzyme treatment sequence were investigated in the hydrolysis of soy protein. Comparing Alcalase vs. Neutrase/Alcalase, it appeared that Neutrase/Alcalase was more efficient than Alcalase alone, as the highest degree of hydrolysis (DH) was seen in Neutrase/Alcalase. A surprisingly high DH (more than 60%) was observed with Flavourzyme in the second hydrolysis. The separation of insolubles from the first hydrolysis had little effect on the second hydrolysis. When the washing water from the first hydrolysis was reused in the next hydrolysis, the DH and protein recovery were increased. The addition of calcium ion showed not so much positive effects by the stabilization of Neutrase on the Protein hydrolysis. The use of carbohydrase and repeated acid washing gave positive effects on DH. The simultaneous treatment using endoprotease and exoprotease with pH adjustment improved DH significantly.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.2
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• pp.1-10
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• 2022

The purpose of this study is to analyze the structural properties of 100% wool fabrics knitted with various stitch types and to evaluate dimensional stability from shrinkage in wet cleaning and drying. Materials were weft-knitted from twenty-four different stitches with 7 gauge using a computerized flatbed knitting machine. Weight, thickness, density, and length were measured. A domestic washing machine and a tumble dryer were used for the shrinkage test. The results are as follows: Knitted fabrics were divided into 3 groups based on weight per unit area. Porous knits show light weight whilst milano, pintuck, rib stitches belong to the heaviest group. A positive correlation between weight and thickness was found and the same result was obtained for wale density and weight. Dimensional shrinkage of knitted fabrics was increased during repetitive wet cleaning and drying regardless of knit stitches. Especially, fabrics knitted with float, tuck, cable, and links & links stitches samples were contracted more than 15% in the first treatment whereas 2x1 rib stitch showed 1% shrinkage rate. Fisherman and milano stitches contracted in both course and wale direction with similar shrinkage rates. However, porous knits with float and tuck stitches shrank in course direction by 20% as well as cable samples contracted from 5% to 20% after repeated washing and drying. On the other hand, 30% and 15% contraction of wale direction occurred in orderly float and links & links stitches, respectively. Machine dried knits have a higher shrinkage rate than air-dried knits, but the drying method did not affect to the direction of contraction. In conclusion, variations of knit, tuck, and float stitches affect knit construction and dimensional stability from shrinkage in wet cleaning and drying of wool knitted fabrics.

• Journal of the Korean Society of Costume
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• v.54 no.6
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• pp.141-148
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• 2004

This study examines the dyeability of fabrics in relation to dyeing temperature, time, concentration, and the number of repeated dyeings. For this study, at first we extracted natural dyes from the peel of C.umshiu mandarin, which is fast as a dye and considered as recycling agricultural wastes. Additionally, it represents the image of Jeju Island. Then, we dyed cotton, wool, silk and nylon fabrics with the extracted dyes. The findings of this study are as follows. 1) Dyed cotton, wool, silk and nylon fabrics with the extract of C.umshiu mandarin peel are generally yellow. 2) Wool, nylon, silk, and cotton, in this order, are of good dyeability; Wool fabrics have the highest dyeability and cotton fabrics have the lowest. The dyeabilty of cotton fabrics was not improved even after dyeing in different conditions. 3) Colorfastness with washing, rubbing and perspiration are all good, while colorfastness with light is poor. 4) Higher dyeing concentration makes better dyeability. 5) Dyeability is enhanced as the dyeing temperature increases, while the dyeability of silk and nylon is relatively good even at low temperatures. 6) Looking at dyeability according to dyeing time, the longer the dyeing time, the better the dyeablility. Sixty minutes of dyeing time is appropriate to dye fabrics. 7) With an increase in the number of repeated dyeings, increased dyeability is obtaihed.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.5
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• pp.665-674
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• 2014

An analysis of the components of clay mineral before and after coloration (XRF) showed that the elements involved in coloration are Fe, Cr, and Ni. Fe accounts for 65% of coloring components on dyed fabric; in addition, Cr and Ni also affect coloring. The optimal coloration condition was to repeat the process of immersing the cotton fabric in $80^{\circ}C$ slurry of 8g of clay mineral to 1g cotton for 60 minutes, dry it for 24 hours and rinse three times. Especially, as the repetition of coloration increased, the $(K/S)_{440}$ value of sample A increased from 1.0 to 2.5, and sample B increased from 1.0 to 1.6. The effect of the repeated process on coloration was significant; consequently, the rinsing and drying process were important to decrease the coloration level. It also showed excellent results in regard to color fastness to washing, light, rubbing, perspiration, and antibiotic effect.

• The Research Journal of the Costume Culture
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• v.31 no.2
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• pp.248-261
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• 2023

The conditions for minimizing dyes and additives when dyeing cellulose fibers such as linen, ramie, and hemp fabrics were obtained using glucose, an organic reducing agent. Dyeability and colorfastness were measured through repeated dyeing. The overall surface dyeing concentration followed the linen>hemp>ramie order, and most of the colors were in the range of PB (PurpleBlue). As the glucose concentration increased, the blue series was strengthened, and the color was dark and clear. It was determined that glucose the concentration of 4g/L was appropriate for minimizing the amount of dye. When the dyeing temperature was 30℃, the surface dyeing concentration was the highest, and the color was dark and clear. Although the dyeing concentration increased as NaOH concentration increased, 3g/L (pH 12.37) was considered appropriate for the minimum NaOH concentration, which becomes gradual after the dyeing concentration increased rapidly. It was found that the surface dyeing concentration, when repeated six times for 5 min, was better than that of dyeing once for 30 min. Washing, rubbing, and perspiration colorfastness were all found to be excellent in grades 4-4-5, and colorfastness to light was excellent in grades 5 of linen and hemp and grade 4 of ramie.

• Journal of Korean Society of Forest Science
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• v.108 no.3
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• pp.341-348
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• 2019

In order to reduce the safety risk of forestry operations, this research was conducted to examine the suitability of chainsaw protective pants after repeated laundering, testing four different products that are currently used in hand-held chainsaw operations. Laundering was repeated 10, 20, 30, 40, and 50 times. After washing, we measured the shrinkage ratio of 17 measurement positions mostly affecting the safety of forest operations and suggested the expected safety life cycle of chainsaw protective clothes. The results showed that most of the products have only one measurement position where the standard shrinkage ratio (<6%) was exceeded after 20 washings, and that the lateral direction of measurement positions shrank more than the vertical one. The numbers of repeated launderings and measurement positions were found to be significant factors influencing the shrinkage ratio (p<0.05). In the shrinkage rates for 17 measurement positions, there were significant correlations between five of the measurement positions (a, b, g, j, and n) and the number of repeated launderings (p<0.05). Therefore, the results suggest that about 10 months would be suitable for an adequate safety lifetime for chainsaw protective pants. The relationship between the number of repeated launderings and the measurement positions will be further analyzed in detail to examine the durability of chainsaw protective pants.

• Economic and Environmental Geology
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• v.48 no.6
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• pp.491-500
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• 2015

Batch experiments were performed to determine the feasibility of the surfactant-enhanced soil washing process at various washing conditions for the Kuwait soil seriously contaminated with the crude oil. The soil was sampled at a dried oil pond in Kuwait and its average TPH concentration was 223,754 mg/kg, which was too high to apply the conventional remediation process. Nine commercialized non-ionic surfactants were used for the batch experiment to measure the surfactant solubility for the crude oil because it was reported that they have worked for the soil remediation. Among them, three surfactants having high crude oil solubility were used for the soil washing experiment. From the result of batch experiment, 5% TritonX-100 washing solution showed the highest TPH removal efficiency (67%) for the crude oil contaminated soil. However, because the residual TPH concentration in the washed soil was still higher than the clean-up level in Kuwait (10,000 mg/kg), the repeated soil washing was performed. After five washings with 2% surfactant solution, the cumulative TPH removal efficiency was higher than 96% and the residual TPH concentration in the soil went down below the clean-up level. To measure the desorption capacity of TritonX-100 remained in the soil after the soil washing, the silica beads and the soil were washed five times with 2% TritonX-100 surfactant solution and then they were washed again with distilled water to detach the surfactant adsorbed on beads or soil. After five washings with surfactant solution, 7.8% and 19.6% of the surfactant was adsorbed on beads and soil, respectively. When additionally washed with distilled water, most of the residual surfactant were detached from beads and only 4.3% of surfactant was remained in soil. From the results, it was investigated that the surfactant-enhanced soil washing process with TritonX-100, Tergitol S-15-7, and Tergitol S-15-9 has a great capability for the remediation of the Kuwait soil seriously contaminated by crude oil (more than 220,000 mg/kg).

• Journal of the Korea Convergence Society
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• v.13 no.3
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• pp.91-103
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• 2022

This study surveyed 101 occupational therapists who were performing occupational therapy before and after the COVID-19 outbreak to compare their perceptions and performance of hand washing, use of personal protective equipment, and infection control of surrounding environment. Mann-Whitney U test, Kruskal wallis H test, Wilcoxon signed-rank test, Pearson's correlation coefficient were used analyzed. As a result, it was confirmed that they received better infection control education after the outbreak compared to before the outbreak of COVID-19, and their experience with infectious diseases was lower. In addition, it was found that the perception and performance of infection control in hand washing, personal protective equipment, and surrounding environment cleaning were improved after the outbreak compared to before the outbreak of COVID-19. However, to this day, hand washing for more than 40 seconds in running water recommended by the Korea Centers for Disease Control and Prevention, cleaning the treatment room, and disinfection of treatment tools are still in need of improvement. Through this study, infection control education should be repeated regularly to minimize the occurrence of infectious diseases, and It will be a basic data that can be used in infection control education and follow-up studies for occupational therapists in the future.