• Journal of the Korean Wood Science and Technology
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• v.23 no.1
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• pp.42-48
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• 1995

The purpose of this study is to evaluate the efficacy of metabolites produced form Streptomyces rimosus in controlling the growth of sapwood - inhabiting fungi. In order to carry out this task, the following specific fungi were tested : sapstain fungi - Ceratocystis pilifera, Ceratocystis piceae, and Aureobasidium pullulans ; mold fungi - Trichoderma hazianum, Trichoderma viride, Penicillium cirtrinum, and Aspergillus niger. Based on the tests, the following observations can be drawn. 1. The conidial germination of sapstain and mold fungi was completely inhibited leaving a clear zone around the paper disc treated with metabolites. The best inhibition was observed in A. pullulans plate and the least in T. viride. 2. Concentration of SB medium for the production of metabolites from St, rimosus affected antifungal activity of metabolites against sapwood - inhabiting fungi. Metabolites prepared from 1/3${\times}$SB medium showed the best activity and the least activity was observed in metabolites form 1/4${\times}$medium. 3. in vivo and in vitro test using wood blocks, treatment of pine sapwood blocks with metabolites also inhibited conidial germination and thus prevented discoloration. 4. Treatment with metabolites did not change the macroscopic structure of wood and did not cause the discoloration of the surface of wood by pigments produced form St. rimosus. In conclusion the results of this study indicate that antifungal metabloites of St, rimosus could be used for the biological control of sapstain and mold fungi.

• The Journal of Advanced Prosthodontics
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• v.12 no.5
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• pp.259-264
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• 2020

PURPOSE. The aim of this study was to investigate and compare the color stability of provisional restorative materials fabricated by 3D printing, dental milling, and conventional materials. MATERIALS AND METHODS. For the experimental groups, two commercially available 3D-printing provisional resins (E-Dent 100; EnvisionTEC GmbH, Germany & VeroGlaze™; Stratasys^®, USA), two dental milling blocks (PMMA Disk; Yamahachi Dental Co., Japan & Telio^®CAD; Ivoclar Vivadent AG, Liechtenstein), and two conventional materials (Alike™; GC Co., Japan & Luxatemp automix plus; DMG, Germany) were used. The water sorption and solubility test were (n=10, respectively) carried out according to ISO4049:2000 (International Standards Organization, Geneva, Switzerland). For the color stability test (n=10), coffee and black tea were used as staining solutions, and the specimens were stored for 12 weeks. Data were analyzed by one-way ANOVA and Tukey's HSD using SPSS version 22.0 (SPSS Inc. Chicago, IL, USA) (P<.05). RESULTS. Alike and Veroglaze showed the highest values and Luxatemp showed the lowest water sorption. In the color stability test, the ΔE of conventional materials varied depending on the staining solution. PMMA milling blocks showed a relatively low ΔE up to 4 weeks, and then significantly increased after 8 weeks (P<.05). 3D-printed materials exhibited a high ΔE or a significant increase over time (P<.05). CONCLUSION. The degree of discoloration increased with time, and a visually perceptible color difference value (ΔE) was shown regardless of the materials and solutions. PMMA milled and 3D-printed materials showed more rapid change in discoloration after 8 weeks.

• Fashion & Textile Research Journal
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• v.10 no.2
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• pp.242-248
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• 2008

This study was aimed to find whether the Chelidonium majus which grows naturally in Korean soil and has a various medical ingredient is valuable as a natural dyeing material and to examine the functionality of Chelidonium majus extract. As the test result of dyeing colorfastness, colorfastness to sunlight was 1st grade for all the dyed fabrics. The colorfastness to laundry for discoloration showed from 1st to 4th grade and that for discoloration showed from 4th to 5th grade through all the dyed fabrics. Colorfastness to perspiration, rubbing, and drycleaning showed from 4th to 5th grade through all the dyed fabrics. In the result of antibiosis test, the dyed cotton fabric showed the bacteria reduction rate of 99.0% for Staphylococcus aureus and Escherichia coli evenly when washed one, three, and five times, The dyed silk fabric, when washed one, three, and five times, showed the bacteria reduction rate of 99.0% for Staphylococcus aureus, but didn't showed the significant bacteria reduction. As the test result of sun protection test, in the case of the cotton fabric which was dyed but don't use mordant, after one-time washing, S.P.F.(Sun Protection Factor) showed 20.4, the interception rate of UV-A showed 94.3%, and that of UV-B showed 95.2%. After five-time washing, S.P.F. showed 14.3, the interception rate of UV-A showed 90.0%, and that of UV-B showed 93.2%. In the case of the silk fabric which was dyed but don't use mordant, after one time washing, S.P.F. showed 30.5, the interception rate of UV-A showed 95.9%, and that of UV-B showed 96.9%, after five-time washing, S.P.F. showed 31.0, the interception rate of UV-A showed 95.6%, and that of UV-B showed 96.7%.

• Fisheries and Aquatic Sciences
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• v.20 no.7
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• pp.13.1-13.7
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• 2017

In order to evaluate the maximal storable period of the raw crab for a non-thermal muscle separation, the quality changes of the leg meat of red snow crab (Chionoecetes japonicus) during freeze storage were investigated. Fresh red snow crabs were stored at $-20^{\circ}C$ for 7 weeks, and the leg muscle was separated by a no heating separation (NHS) method every week. During the storage, considerable loss of the leg muscle did not occur and microbiological risk was very low. In contrast, discoloration appeared at 2-week storage on around carapace and the leg muscle turned yellow at storage 3-week. In physiochemical parameters, protein and free amino acids gradually decreased with storage time, expected that proteolytic enzymes still activated at $-20^{\circ}C$. At 4-week storage, the sensory acceptance dropped down below point 4 as low as inedible and notable inflection points in pH and acidity were observed. The volatile base nitrogen was low, though a little increase was recorded. These results suggested that the maximal storable period at $-20^{\circ}C$ of the raw material was within 2 weeks and it was depended on external factor such as the discoloration. The present study might be referred as basic data for approaches to solve quality loss occurred in non-thermal muscle separation.

• Journal of Conservation Science
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• v.29 no.1
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• pp.1-14
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• 2013

The Hongjimun Ogansumun (Five-arched floodgates) is composed mainly of biotite granite, pink feldspar granite and granodiorite that are very similar with granitic rocks around the Seoul. Main damage in the floodgates was gray, yellow and predominantly white discoloration on the surface of stone blocks. All floodgates showed more discoloration in the wall than ceiling, and there were growing stalactite on the ceiling. Scientific analyses determined that the white discoloring substrates were mainly calcite. Therefore, conservation treatment was carried out to remove the substrates by using dry cleaning, high pressure cleaning and chemicals. The floodgates have been restored to good state, but it is still significantly necessary to install drainage on the top of the gates.

• Journal of the Korea Furniture Society
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• v.12 no.1
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• pp.11-20
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• 2001

To investigate weathering and surface characteristics of coating film on lumbers coated with Hwangchil(varnish of Dendropanax morbifera), we carried out to investigate the resistance against discoloration, value of crack and surface characteristics of coating films on seven domestic lumbers and those of four introduced tropical lumbers. There was investigated to evaluate the properties of coating films by the varnish of Dendropanax morbifera. There was insignificant correlations between the hardness and moisture contents of each lumber treated by the varnish. There was no significant correlations between the thickness of coating film and the hardness, either. Although we investigated 11 wood species, we found only three species as resistance wood species against discoloration; Diospysos spp., Abies holophylla and Ulmus davidiana. The crack of coaing films was the largest on Zelkova serrata followed by Juglans sinensis, Cercidiphum japonicum, Tectona grands, Ulmus davidiana, Guibourtia tessmannii, Diospysos spp. and Dalbergia latifolia. However, there was no crack of coating films on the lumbers of Juniperus rigida, Prunus serrulata var. spontanea and Abies holophylla. The crack of coating film showed positive correlations with the thickness of coating film and hardness. The surface characteristics of the coating films evaluated on the basis of $R_{a}$ values indicated the lumbers of Ulmus davidiana($0.14{\;}{\mu}m$), Juniperus rigida($0.1 5{\;}{\mu}m$), Guibourtia tessmannii($0.19{\;}{\mu}m$), Dalvergia latifolia($0.20{\;}{\mu}m$) and Diospysos spp.($0.20{\;}{\mu}m$), Cercidiphum japonicum($0.24{\;}{\mu}m$) as good species while there was insignificant differences between softwoods and hardwoods. Tectona grands, Prunus serrulata var. spontanea and Abies holophylla showed rough surface with $1.53~2.63{\;}{\mu}m$ of $R_a$ values. The four kinds of rough indices($R_a,{\;}R_z,{\;}R_{max}{\;}and{\;}R_q$) showed very low correlations with moisture contents with the correlation coefficients. The $R_a{\;}and{\;}R_{max}$ also showed slight relationship with hardness.

• The Research Journal of the Costume Culture
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• v.17 no.2
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• pp.216-224
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• 2009

This study was accomplished to examine the dyeing property and functionality of both cotton and silk fabrics dyed with clove extract. The purpose of this study was to investigate the effects of dyeing property, antibiosis, and sun protection effectiveness for a clove. The study method used in this study was the experimental research to extract dyestuffs from a clove, to treat dyestuffs with a mordant, and then to measure dyeing colorfastness, antibiosis, and sun protection for dyed fabrics. As a result of the test for dyeing colorfastness, in the case of colorfastness to laundry, the degree of discoloration showed grade $1\sim4$ and the degree of pollution showed grade $4\sim5$. Colorfastness to perspiration for both cotton and silk fabrics dyed showed grade $1\sim2$ to $4\sim5$. Colorfastness to sunlight showed grade 2 to $4\sim5$. Colorfastness to rubbing showed grade $3\sim4$ to $4\sim5$. In the colorfastness to dry cleaning, the degree of discoloration showed grade $3\sim4$ and the degree of pollution showed grade $4\sim5$. As a result of the antibiosis test, for the Staphylococcus aureus, both cotton and silk showed the bacteria reduction rate of 99.9% even after five times laundry, and for the Escherichia coli, cotton fabrics showed the bacteria reduction rate of 99.9% only after one time laundry, but silk fabrics showed the bacteria reduction rate of 99.9% even after five times laundry. As a result of the test for sun protection effectiveness, dyed silk fabrics showed the result more excellent than dyed cotton fabrics.

• 보존과학연구
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• s.24
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• pp.81-98
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• 2003

The biodeterioration on Iksan Mireuksaji pagoda has been studied with fucus on application of K201 as a chemical treatment. Total of 39species, including 10 algae, 16 lichens, 6 mosses and 7 unidentified bacteria and fungi, were collected and identified on the surface of the pagoda. Most of them caused serious discoloration on the surface. The effectiveness and stability of K201 was examined by applying it on some part of the pagoda. A mild spraying of solution diluted to half of original reagent was good enough to eliminate all the deteriorating species on the surface. Most of discoloration disappeared after the treatment except the red color caused by iron substance. The effectiveness of the regent was compared with water wash. The stone was first washed with water and the dirt on the surface was scrubbed off from the surface. The initial surface of the stone was clearer in water wash. However, many of the deteriorating species reappear in 4 weeks after water wash. Although spraying of the reagent K201 could noteliminate all the remnant of dead organisms as good as scrubbing the surface, no deteriorating algae or lichen was observed until two month after treatment. Therefore, spraying method with chemicals seems more stable and reliable way to remove the biodeterioration than physical scrubbing of the surface.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.603-608
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• 1998

Lipid oxidation in ascidian was studied when fresh, deshelled and sliced meats were fermented for 50 days at 5$\pm$2$^{\circ}C$ with 8%(w/w) salt and 0.1% papain. Antioxidative effects of butylated hydroxytoluene(BHT) and carotenoid extracts from ascidian tunic on lipid oxidation and oxidationrelated discoloration of ascidian meat during fermentation were investigated. Changes in peroxide value, carbonyl value, thiobarbituric acid value, fatty acids composition, the loss of total carotenoid and sensory evaluation were determined to assess the rancidity. Peroxide and carbonyl values in BHT and carotenoid extract treatments increased less than those of the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control but it increased slowly until 40 days in cases of 0.02% BHT or 0.02% BHT with 0.05% carotenoid added. Fatty acids of fresh ascidian composed of polyenoic acid, saturated acid and monoenoic acid of 51.5%, 28.1% and 20.7%, respectively. Saturated fatty acids(C16:0, C14:0, C18:0) and monoenoic acids(C18:1, C16:1) increased while polyenoic acids(C20:5, C22:6) decreased during fermentation. Carotenoid was markedly degraded and discolored in the control during fermentation. But 0.02% BHT and 0.05% carotenoid treatments had bright color like fresh meat during 40 days. The results of sensory evaluation during the fermentation also convinced the retard of discoloration by the addition of BHT and carotenoid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.211-214
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• 1988

The thermal drying of chestnut powder showed a distinct discoloration from yellow to reddish brown color and resulted in a decrease in lysine content of chestnut protein. Chanted powders were blanched in hot solutions of 0.1% sodium bisulfate, 0.2% alum, 0.05% vitamin C and 0.1% citric acid and dried for 7 days in $50^{\cire}C$ of heatine drier. The color difference values in contrast with the original chestnut powder were 1.05, 1.24, 3.47 and 3.34, respectively. In particular, the effect of 0.1% potassium metabisulfide was distinguished. Under the blanching conditions used, a blanching period of 3 min resulted in the most favorable color of chestnut powder.