• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.399-408
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• 2001

Tooth bleaching has been prevailing recently for its ability to recover the color and shape of natural teeth without reduction of tooth material. However, it has been reported that bleaching procedure adversely affects the adhesive bond strength of composite resin to tooth. At the same time the bond strength was reported to be regained by application of some chemical agents. The purpose of this in vitro study was to investigate the effect of the removal of residual peroxide on the composite- enamel adhesion and also evaluated fracture mode between resin and enamel after bleaching. Sixty extracted human anterior and premolars teeth were divided into 5 groups and bleached by combined technique using of office bleaching with 35 % hydrogen peroxide and matrix bleaching with 10% carbamide peroxide for 4 weeks. After bleaching, the labial surfaces of each tooth were treated with catalase, 70% ethyl alcohol, distilled water and filled with composite resin. Shear bond strength was tested and the fractured surfaces were also examined with SEM. Analysis revealed significantly higher bond strength values. (p＜0.05) for catalase-treated specimens, but water-treated specimens showed reduction of bond strength, alcohol- treated specimens had medium value between the two groups(p＜0.05). The fracture mode was shown that the catalase group and the alcohol group had cohesive failure but the water sprayed group had adhesive failure. It was concluded that the peroxide residues in tooth after bleaching seems to be removed by gradual diffusion and the free radical oxygen from peroxide prevents polymerization by combining catalyst in the resin monomer. Therefore it may be possible to eliminate the adverse effect on the adhesion of composite resin to enamel after bleaching by using water displacement solution or dentin bonding agent including it for effective removal of residual peroxide.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.2
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• pp.143-148
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• 2008

Variations of the seventeen amino acids(aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, cystein, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, histidine, lysine, arginine) were analyzed in human hair sample by amino acid auto analyzer(AAA). The effect of bleaching and permanent wave manipulation on the amino acid composition of hair were investigated. Hair samples were collected from 10 males in their thirties. Hair samples were treated with 10 mL of 6 N hydrochloric acid at $110^{\circ}C$ for 24 h and analysed by AAA. The results showed that the amino acid content of normal hair(73.9%) decreased to 71.5% and 69.3% after bleaching and permanent wave treatment, respectively. Furthermore, mean contents of lysine and tyrosine in amino acids showed obviously decreased about 25% by permanent wave and bleaching treatment. On the other hand, serine, cystein, leucine and histidine were not changed.

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.66-68
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• 1987

The qualitative and quantitative analyses of phospholipids in chloroform-methanol extracted crude and hexane extracted deodorized soybean oils were carried out by High-Performance Liquid Chromatography (HPLC). The phosphorus contents in hexane extracted crude, degummed, refiend, bleached and deodorized soybean oil were 510, 120, 5, 1.4 and 1 ppm, respectively. The chloroform-methanol extracted crude soybean oil had 800 ppm phosphorus. The phospholipids found in crude oil were phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine and phosphatidic acid. Only phosphatidylchonine and phosphatidylethanolamine were detected in the deodorized soybean oil. The HPLC method described in this report can separate and detect individual phospholipids in soybean oil at 0.1 ppm level in 30 min.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.1
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• pp.135-145
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• 2017

In order to analysis on color difference of yellow natural dyes, I have dyed cellulose and protein fabrics. The results of experiment have been analysed by wavelength of maximum absorption, amounts of dye uptake, color difference, Hunter's value and Munsell's value. The results from these analyses are as follows : Bud of pagoda tree, Amur cork, and Curcuma showed greenish yellow color, Gardenia Jasminoides showed reddish yellow color. Barberry root showed reddish yellow color with post-mordanting method on cellulose fabric. Moreover, Dupioni silk was dyed in reddish yellow color by Barberry root and Rhubarb. In addition to Chroma index, Gardenia Jasminoides and Curcuma showed clear color overall. However, dyeing rayon and silk by Barberry root, and dyeing silk by Rhubarb showed clear color. Comparing all the results to actual dyed materials, Bud of pagoda tree had small dye uptake, and both ${\Delta}a$ and ${\Delta}b$ value were short which can't recognized the yellow color easily. Dye uptake of Amur cork and Gardenia Jasminoides was small just like Bud of pagoda tree. However, ${\Delta}b$ value order was Gardenia Jasminoides>Amur cork>Bud of pagoda tree. Therefore, Gardenia Jasminoides recognized reddish yellow because of big value of red color and yellow color. In case of Barberry root and Rhubarb which have larger dye uptake, Baberry root recognized yellow color on rayon only, and couldn't recognized yellow color on bleached cotton fabric, ramie, silk, and dupioni silk. Rhubarb recognized yellow color on rayon with pre-mordanting method only, but recognized silk and dupioni silk as brown like color. Moreover, we could not analyze color by dye uptake, Lab, and H(v/c) for Barberry root and Rhubarb. As a result, I think we need to attach color table for the research paper which handled the color of dyeing materials.

• Applied Microscopy
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• v.36 no.1
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• pp.25-33
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• 2006

This study applied a bleaching agent. which is commonly used in the beauty salons, to the hair of normal adult women, collected the hair immediately and 10 days and 20 days from the bleaching, were investigated the degree of degradation of the hair by using scanning and transmission electron microscopes. The surface of hair just after bleaching was observed to be similar to that of normal hair, showing no split or damage of scale. In the hair of 10 days after bleaching, however, the scale came off. From this time, scale on the cuticular layer of hair began to be separated. In 10 days from bleaching, the scale on the cuticular layer was separated from hair and some cytoplasm of cuticular cells was broken into pieces or fell off. The cell remains made the surface coarse and uneven. At this period, damaged scales had a sharp end. In the hair of 20 days after bleaching, scale fell off from the whole surface of the hair and the surface looked rough. On the bleached hair, many vacuoles were formed in the endocuticle of cuticular cells. As a result, deformation caused by the formation of vacuoles in cuticles broke up the cuticular cells.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.169-179
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• 1994

The purpose of this study was to compare and evaluate the bleaching efficacy of three nonvital bleaching techniques: Walking bleaching, Walking bleaching and heat application, and Walking bleaching and bleaching light application. 36 extracted anterior teeth with intact crowns were immersed in 5 % sodium hypochlorite solution for twenty-four hours to loosen extrinsic debris. Lingual access openings were prepared in all teeth and the pulps were extirpated. The teeth were stored in 5% sodium hypochlorite for twenty-four hours to open the dentinal tubules and they were stained via whole blood. Once the teeth were stained, they were evaluated with Colorimeter. The teeth in each group were ranked from lightest to darkest and divided equally into three experimental groups in which the following bleaching techniques were used. Intracoronal base was placed 2mm below cementoenamel junction. Group 1 Walking bleaching (Superoxol + Sodium perborate) Group 2 Heat application + Walking bleaching (Superoxol+Sodium perborate) Group 3 Light application+Walking bleaching (Superoxol+Sodium perborate) The bleaching agents were changed every 3 days and the teeth were bleached for a total of 14 days. The teeth were evaluated with Colorimeter before the start of any bleaching and on day 14. The results were as follows: 1. At the end of 14 days, all the sample teeth demonstrated the increase of Lightness Index at cervical 1/3 of crown (p<0.05) Lightness Index was significant difference in group 2 and 3, but there were some minor differences among groups (p>0.05). 2. In all groups, there was significant difference in red chromacity (p<0.05), but there were some minor differences among groups (p>0.05). 3. In all groups, there was no significant difference in yellow chromacity (p>0.05).

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.57-64
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• 1988

The present study was conducted to characterize lipoxygenase isoenzymes isolated from germinating soybean seeds to obstain pH profiles, carbonyl Production, carotene bleaching abilities, and stability to heat. The roles of these lipoxygenase isoenzymes in the generation of volatile carbonyl compounds were investigated to associate with off-flavor and odor of soybean sprouts cooked to different temperatures. Lipoxygenase isoenzymes were isolated from soybean sprouts using ammonium sulfate fractionation, gel filtration and ionexchange chromatography. Two main lipoxygenases exhibited maximum activity at pH 6.5 (lipoxygenase 2) and at pH 9.5 (lipoxygenase 1), respectively. Both lipoxygenase 1 and 2 produced 280 nm absorbing carbonlys and bleached carotene. The abilities of hydroperoxide formation, 280 nm absorbing carbonyl production and carotene bleaching of lipoxygenase isoenzymes were decreased significantly as the cooking temperature raised. Sensory evaluation data presented that raw and $50^{\circ}C$ cooked soybean sprouts showed significantly higher grassy odor than $80^{\circ}C$and $100^{\circ}C$ cooked soybean sprouts. On the other hand beany odor was significantly higher in $50^{\circ}C$ and $80^{\circ}C$ cooked soybean sprouts than in raw and $100^{\circ}C$ cooked soybean sprouts. These results indicate that lipoxygenase plays a role in the development of off-odor and flavors in soybean sprouts under the condition of chewing and inadequate heating.

• Textile Coloration and Finishing
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• v.8 no.3
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• pp.8-15
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• 1996

Three pieces of cotton fabrics used for this study were exhumed in the Mt.Moo Deung near Kwang Ju in 1965. The fabrics were remains of Jang Heung Lim Si-the nephew's wife of General Kim Deok Ryeong. It was reported that Jang Heung Lim Si died in 1615. The cotton fabrics were classified into three, A, B and C, according to their color. The fabric A was inherent color of cotton, the fabric B was that of light brown and the fabric C was that of dark brown. The physical and chemical characteristics of the cotton fabrics were examined. In the meantime the construction of cotton fabrics and traditional dyeing of Yi dynasty were studied through various records. The results were as follows: 1. According to electromicroscopic examination, the lumen in the cotton fiber had not been developed enough, therefore the quality of cotton at that time was supposed to be not so excellent. 2. The results of chemical analysis indicated that: (1) While the copper number of the cotton fabric A was similar to that of bleached cotton, that of the fabric C was extremely high. (2) The amount of methylene blue absorption was much more than that of normal cotton. (3) The content of cellulose was less than that of normal cotton. (4) The degree of polymerization was less than that of normal cotton. From the results mentioned above, it was concluded that the cotton fabrics were oxidized slowly in the closed lime coffin for a long period of time. From this process of oxidization and deterioration, the degree of polymerization was decreased through depolymerization, and carboxyl groups were produced by the oxidization at reducing end groups. 3. It was confirmed that the cotton fabric C was dyed by the juice of immature persimmon. Thus, it was inferred that the large amount of copper number of cotton fabric C was derived from phenolic OH groups of tannins having high reducing properties in persimmon.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.311-316
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• 2006

The role of short fibre pulp - Mixed Harwood, Eucalyptus, Aspen, Birch, etc for the manufacture of different grades of paper is very well recognized. At the same time, lots of efforts are in progress to maximize the advantages while preserving their own special property. Bleached Acacia Kraft Pulp (BAKP) is comparatively new entry but gained quick recognition. BAKP was introduced to the world market by South East Asian suppliers in the late 1990's. This paper discusses in detail the role and opportunities of use of short fibre pulps. A logical technical comparison has been made between BAKP and another short fibre grades. BAKP being a short, thin-walled fibre shows several similarities with Eucalyptus pulp in terms of good bulk and stiffness. Refining energy and strength properties are very similar, but the shorter fibres and thinner cell walls give an outstanding opacity and formation compared to other commercial short fibre pulps. The collapsed and band-shaped nature gives a matchless smoothness, enabling less calendaring and exceptional printing properties. BAKP is shown to give several advantages to fine paper manufactures, compared with a number of established short fibre pulps such as Brazilian and Chilean Eucalyptus, Canadian Aspen and Indonesian Mixed Hardwood. It is important to consider refining and calendaring conditions to achieve optimum performance. For outer layers of multiply board, Acacia gives excellent coverage due to its high opacity and uniform fibre distribution. Its low roughness property gives improved printability. For tissue products, Acacia gives unique property of superior softness both in terms of hand feel and bulk softness. The high fibre population gives an impression of much higher quality due to the higher opacity and good formation.

• Korean Journal of Materials Research
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• v.29 no.6
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• pp.385-391
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• 2019

In the present study, vanadium oxide($V_2O_5$) films for electrochromic(EC) application are fabricated using sol-gel spin coating method. In order to optimize the EC performance of the $V_2O_5$ films, we adjust the amounts of polyvinylpyrrolidone(PVP) added to the solution at 0, 5, 10, and 15 wt%. Due to the effect of added PVP on the $V_2O_5$ films, the obtained films show increases of film thickness and crystallinity. Compared to other samples, optimum weight percent(10 wt%) of PVP led to superior EC performance with transmittance modulation(45.43 %), responding speeds(6.0 s at colored state and 6.2 s at bleached state), and coloration efficiency($29.8cm^2/C$). This performance improvement can be mainly attributed to the enhanced electrical conductivity and electrochemical activity due to the increased crystallinity and thickness of the $V_2O_5$ films. Therefore, $V_2O_5$ films fabricated with optimized amount of PVP can be a promising EC material for high-performance EC devices.