• 보존과학연구
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• s.28
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• pp.121-147
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• 2007

A large variety of mineral pigments has been used for Korean paintings and it has known that organic pigments have been used together on the Buddhist painting and the portrait. Haehakbando-do, which is from Honolulu Academy Museum in the United States, 12-fold screen was commissioned by Court of the late Joseon Dynasty in order to pray for the King's longevity. Therefore, it seems that all material used including pigments were selected very carefully and a great deal of technical effort was gone into its process. The purposes of this research were to estimate the pigments and the contributory elements of each color used on Haehakbando-do, in accordance with the conservation treatment carried out by Gochang Conservation Institute throughout last year. Without extracting sample, property of pigment was measured by nondestructive method, X-ray spectral analysis, and by comparing with the data about ancient pigments. In spite of the limited range of pigment analysis by nondestructive method, it should be noted that this method would not cause damage to the cultural properites. White pigment was found in all colored parts except the background, so it can be suggested that white color was used as a grounding of other color pigments. This would be flake white[$2PbCO_3{\cdot}Pb(OH)_2$] as Pb was found. Pb was the only element could be found in yellow, however, it can be organic pigment like Gamboge as same as background. Red would be Cinnabar (HgS) as hydrargyrum (Hg) was detected. For the light purple in cloud, organic pigments were probably used since any element is not detected except for Pb, which is used for background. It is possible that green color is the mixture of Malachite[$CuCO_3{\cdot}Cu(OH)_2$] and Azurite [$2CuCO_3{\cdot}Cu(OH)_2$], which share Cu as their main element. Azurite[$2CuCO_3{\cdot}Cu(OH)_2$] was used for bluish pigments. Black is carbon compound. For gold, solid gold (Au) was detected. It shows that gold was gilded on the flake white background. Red painted on the frame of screen was identified as Cinnabar (HgS) and the gold pattern was solid gold (Au). The supporting leg of folding screen was made of brass because both copper and zinc were detected. In conclusion, white pigment was used as grounding of all colors of Haehakbando-do, and specific pigments were used for each color. Additionally, result from the analysis of several pigments shows that mineral pigment and organic pigment, or different mineral pigments were mixed to make various colors.

• Korean Journal of Heritage: History & Science
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• v.47 no.1
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• pp.18-31
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• 2014

This study aims at identifying of characteristics and types of the pigments used for Dancheong(surface decorative and protective pigments) of Yaksajeon Hall in Gwallyoungsa Temple using a Micro-XRF, XRD, SEM-EDS and thereafter, comparing it with the pigments of the wall painting in the same building and with Dancheong pigments of Daeungjeon Hall. The results can be briefly summarized as two points. First, different types of pigments for red, green and white colours had been applied based on different parts of the building and more than two different pigments had been mixed to produce various colours in so me parts. Second, scientific analysis has confirmed that raw minerals for each colour groups are: Cinnabar, minium and Hematite for red; white clay and oyster shell white($Al_2O_3{\cdot}SiO_2{\cdot}4H_2O$) for white; Atacamite and Celadonite for green; carbon(C) for black; Yellow Ocher for yellow; and Lazulite for blue. Comparative analysis of such result with that of the wall paintings and of Dancheong of Daeungjeon Hall has revealed that similar minerals had been used in overall except that several different pigments had been added or removed for making green, white and yellow colour groups in some parts. In conclusion, the result has displayed that painters had used different ways of producing pigments by a type of painting or a building within the same period or for the buildings in the same buddhist temple compound.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.302-310
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• 2019

This study was conducted to investigate the effects of LEDs on the fruit qualities of two strawberry (Fragaria ${\times}$ ananassa Duch.) cultivars such as hardness, phytochemicals, and antioxidant activity using the strawberry fruits, which were harvested by 50% and 100% ripening levels of fruits grown under LEDs illuminated during 6 hours after sunset from November 2018 to January of the following year. In the hardness of strawberry fruit, when two strawberry cultivars were illuminated red LED light, in 50% ripening as well as 100% ripening fruit of both 'Daewang' and 'Seolhyang' cultivars were significantly higher compared to other treatments. Also, in the sugar content on 50% ripening fruit of two cultivars, the fruit of red LED light was significantly higher than in the other LEDs and control. On the other hand, in the acidity of 50% and 100% ripening levels of strawberry fruit, the fruit under control condition was higher in than that of LEDs. The phenolic compounds of strawberry fruit grown in control was much higher than that of strawberry treated with LEDs. However, the influence of LEDs on flavonoid and anthocyanin content of strawberry fruit did not affected. Changes in the phytochemicals contents of the strawberry tends to be affected depending on the maturity of fruit. Antioxidant activity such as DPPH and ABTS of were not different by maturity of fruit, and supplementation of LEDs during 6 hours at night. Therefore, we concluded that lighting of LEDs is effective for fruit quality in terms of sugar accumulation and fruit hardness.

• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.299-310
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• 2021

Glycerol is a non-volatile compound with no aromatic properties that contributes significantly to the quality of wine by providing sweetness and richness of taste. In addition, it is also the third most significant byproduct of alcoholic fermentation in terms of quantity after ethanol and carbon dioxide. In this study, Fourier transform infrared (FT-IR) spectroscopy was employed as a fast non-destructive method in conjugation with multivariate regression analysis to build a model for the quantitative analysis of glycerol concentration in wine samples. The samples were prepared by using three varieties of red wine samples (i.e., Shiraz, Merlot, and Barbaresco) that were adulterated with glycerol in concentration ranges from 0.1 to 15% (v·v^-1), and subjected to analysis together with pure wine samples. A net analyte signal (NAS)-based methodology, called hybrid linear analysis in the literature (HLA/GO), was applied for predicting glycerol concentrations in the collected FT-IR spectral data. Calibration and validation sets were designed to evaluate the performance of the multivariate method. The obtained results exhibited a high coefficient of determination (R²) of 0.987 and a low root mean square error (RMSE) of 0.563% for the calibration set, and a R² of 0.984 and a RMSE of 0.626% for the validation set. Further, the model was validated in terms of sensitivity, selectivity, and limits of detection and quantification, and the results confirmed that this model can be used in most applications, as well as for quality assurance.

• Elastomers and Composites
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• v.37 no.4
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• pp.224-233
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• 2002

This study has investigated the flame retardant properties of EPDM rubber with the addition of various flame retardants. Carbon black, stearic acid, zinc oxide cross-linking agent were mixed with EPDM rubber to produce the base rubber E0 without the addition of flame retardants. Phosphorus flame retardant Tricrecyl phosphate(TCP) was added to E0 in 0.5, 1, 1.5, 2 phr to make E1~E4 samples and red phosphorus was added in 3, 6, 9, 12 phr to make E5~E8 samples. A flame retardant of the bromine family Decabromodiphenyloxide(DBDPO), and a chlorinated paraffin retardant of the chlorine family was added to E0 in 3, 6, 9, 12 phr to make E9~E12 and E13~E16 samples, repectively. Basic physical properties such as tensile strength, tear strength and hardness were measured for all the rubber samples with various flame retardant additions. There was no substantial differences. On the other hand, Oxygen index and UL94 were measured to study flame retardant properties. From oxygen index measurements E0 sample showed a value of 23.5%, indicating the improvement of flame retardant properties. Also from UL94 measurements, it was found that addition of red phosphorus resulted in maximum flame retardant effect. It was found that increasing the amount of addition resulted in decreasing combustion rate and improving flame retardant effect regardless of the kind of flame retardant.

• Journal of Life Science
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• v.34 no.6
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• pp.377-384
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• 2024

Prodigiosin is a red pigment characterized by a common pyrrolylpyrromethane skeleton. It is produced by Serratia marcescens, Vibrio psychroerythrus, Hahella chejuensis, etc. Prodigiosin has been reported to possess anticancer, immunosuppressant, antifungal antimalarial, and algicidal activities. However, despite prodigiosin's diverse range of activities, its production rate is significantly low and biosynthesis conditions are difficult. Consequently, the selling price is high, and its usability is limited. This study aimed to increase the efficiency of prodigiosin production according to the culture conditions of Serratia. In this study, a bacterial strain PDGS¹²⁰⁹¹⁵ producing prodigiosin was isolated from lightly contaminated stream water in Busan and identified as a strain of Serratia sp. based on 16S rDNA gene sequence analysis and physiological characteristics. The reddish pigment from PDGS¹²⁰⁹¹⁵ was directly extracted using acidified ethanol, and a characterization analysis confirmed that it was a prodigiosin compound. The optimal conditions for pigment production were 25℃, pH 7, and 0% NaCl concentration for a duration of 14 hr. Furthermore, by treating carbon and nitrogen sources, such as fructose and beef extract, respectively, prodigiosin production increased approximately six-fold and four-fold. Among the minerals tested, 0.1% KCl was found to be the most effective for prodigiosin production. Moreover, casein was identified as the most suitable source for prodigiosin production.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.107-116
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• 1998

In an effort to reduce artifically the residual pesticides on crop and soil by accelerated photolysis,some 40 among the naturally occurring and synthetic coumpound were screened for photosensitization and/or photocatalysis and six promising chemicals were selected.The fungicides and the four selected photosensitizers and/or photocatalyst (PS) were applied to each crop.The results obtained are summarized as follows. 1. The wavelengths of maximum absortion (${\lambda}$max) and the molar absorptivites (${\varepsilon}$max) of procymidone,vinclozolin,and carbendazim in acentone were all 209 nm and 853,854,and 8740 respectively. 2. Of the 40 naturally-occuring and synthetic compounds screened,six promising ones were selected and designated as PS-1 (aromatic ketone),PS-2(aromatic amine)PS-3(quinone) ,PS-4 (inorganic compound),PS-5(organic acid salt) and PS-6(semiconductor photocatalyst). 3. In the accelerated photolysis of pesticide in soil by applying PS ,procymidone was decoposed rapidly by virtue of PS-2,being 59% of the control 3 days after application. 4. The vinclozolin residue in soil was reduced to 71% and 21% of the control 1 and 15 days,respectively,after PS-2 application. 5. The photolysis of carbendazim in soil was not accelerated by any of the PS tested. 6. The pesticide residues on the crop were prominently reduced by PS application.The procymidone residue on tomato was reduced to 47% of the control 15 days after PS-1 application and that on red pepper reduced to 57% 15 days after PS-2 application. 7. Vincrozolin residus remaining on tomato 1 and 15 days after PS-2 application were 38% and 56% of the control whereas those on the red pepper were 82% and 64%,respectively. 8. PS-2 was the most effective for the accelerated photolysis of carbendazim residues remaining on tomato, whereas on red pepper, the four of PS tested were all effective, but did not make much difference between them. This might be due to the shielding of sunlight by the leaves of red pepper not to exert the photosensitizing effect of PS-2 to the full.

• Journal of Ginseng Research
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• v.33 no.2
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• pp.104-110
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• 2009

It is well known that the saponin of Korean red ginseng (KRG) has an anti-oxidant effect and could suppress the accumulation of lipid peroxidation. The aim of the present study was to observe the inhibitory effect of KRG on mice with noise-induced hearing loss, and to determine its optimal dose. BALB/c mice with a normal hearing level and normal Preyer's reflexes were used in the study. The mice in the permanent-threshold-shift (PTS) group were exposed to noise (120-dB SPL, white noise band) in a noise booth for 3 h a day, for three consecutive days. The mice in the experimental group were given heat-processed red-ginseng extract (50 mg/kg, 100 mg/kg, and 200 mg/kg), and those in the control group were given normal saline alone during their noise exposure. The mice in the temporary-threshold-shift (TTS) group were exposed to noise (120 dBSPL, white noise band) in a noise booth for 3 h. The mice in the experimental group were given heat-processed red-ginseng extract (50 mg/kg, 100 mg/kg, and 200 mg/kg), and those in the control group were given normal saline alone before their noise exposure. The hearing levels of the mice were measured through auditory brainstem response (ABR) immediately and I, 3, 5, 7, and 14 days after their noise exposure. Cochleae were removed from the mice 14 days after their noise exposure. lmmunochemical and immunofluorescent staining were performed to observe the expression of 8-oxoG in cochlea. In the PTS group, the hearing function of the mice in all the groups was not recovered after their noise exposure. In the TTS group, however, the hearing function of the mice in all the groups was recovered within 14 days. Reduced hearing impairment and early recovery were observed in the mice that were given 200 mg/kg KRG, and early recovery was observed in the mice that were given 100 mg/kg KRG The immunopositive staining of 8-oxoG was detected in the stria vascularis in the control group but was diminished in the mice that were given 200 mg/kg KRG The ingestion of more than 100 mg/kg KRG demonstrated a protection and recovery effect on the noiseinduced-TTS group. Since KRG has been reported to be a safe compound even up to hundreds of mg/kg, a higher concentration of it may effectively protect and recover TTS.

• Macromolecular Research
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• v.17 no.10
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• pp.734-738
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• 2009

Biodegradable, pH-sensitive, glycol chitosan (GC) hydrogels were prepared using divinyl adipate (DVA) as a crosslinker and acetic acid as a catalyst. DVA has highly reactive double vinyl ester groups and GC contains a high density of hydroxyl groups, with two in every glucosamine unit. The transesterification reaction between vinyl esters and hydroxyl groups produced crosslinked GC hydrogels. The initial crosslinking reaction was monitored by measuring the viscosity of the reaction mixture. When DVA was added to the GC solution and heated to $50^{\circ}C$, the viscosity of the GC solution gradually increased, implying a crosslinking reaction and hydrogel formation. A new peak from the ester group was observed in the FTIR spectra of the GC hydrogels, confirming the crosslinking reaction. The synthesized GC hydrogel showed pH-dependent water absorbency, mainly due to the presence of amine groups ($-NH_2$) at the C-2 position of the glucosamine unit of GC. The water absorbency greatly increased at acidic pH and slightly decreased at alkaline pH. The GC hydrogel gradually degraded in $37^{\circ}C$ water due to hydrolysis of the ester bonds, which were intermolecular crosslinking sites. A red dye, 5-carboxyltetramethyl-rhodamine (CTMR), was entrapped in the GC hydrogels as a model compound. CTMR was released from GC hydrogels in two steps: an initial burst release mainly due to desorption and diffusion, and a second sustained release possibly due to gradual degradation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.243-249
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• 2007

The French paradox has been attributed to the antioxidant properties of flavonoids present in the red wine. Amentoflavone(AF) is a bi-flavonoid compound with anti-fungal and anti-inflammatory activities. We isolated AF from Selaginella tamariscina, and studied its effects on nuclear factor-B(NF-B)-mediated MMP-9 gene expression in RAW264.7 cells. AF blocked the lipopolysaccharide(LPS)-induced expression of MMP-9. Zymographic and immunoblot analyses showed that AF suppressed LPS-induced MMP-9 expression in a dose-dependent manner. To clarify the mechanistic basis for its inhibition of MMP-9 induction, we examined the effect of AF on the transactivation of MMP-9 gene by luciferase reporter activity using -1.59 kb flanking region. AF potently suppressed the reporter gene activity. This inhibition was characterized by down-regulation of MMP-9, which was transcriptionally regulated at NF-B site and activation protein-1 (AP-1) site in the MMP-9 promoter, two important nuclear transcription factors that are involved in MMP-9 expression. These findings indicate the efficacy of AF in inhibiting MMP-9 expression through the transcription factors NF-B and AP-1 on LPS-induced RAW264.7 cells.