• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.8
• /
• pp.176-182
• /
• 2018

One of the most important factor of esthetic prosthesis is the color of the teeth. Zirconia is produced in the process of design, milling, coloring, drying, and sintering. The effect of the drying degree of zirconia colorant on the color tone is examined. For the experiment, a total of 45 zirconia specimens(15 for each) were fabricated by using cad/cam system. The zirconia specimens(L block(LAZOR), Z block(Zircos-E block posterior), A block(AlphaZ)) were then subjected to zirconia sintering in accordance with the manufacturer's instructions, using a chemical coloring agent to Non-drying(0sec), intermediate (10sec), and completely dried (10min) temperature holding times. The color tone was measured using a spectrophotometer. The results were analyzed with a One-way analysis of variance and the Tukey post-hoc test (${\alpha}=.05$) The $L^*$ values of L, A specimens, $a^*$ values of A specimens, and $b^*$ values of Z specimens were not statistically different according to the degree of drying (p>0.05), While the $L^*$ value of Z specimen, $a^*$ value of L, Z specimen, $b^*$ values of L, A specimens were statistically different according to the degree of drying(p <0.05). In conclusion, the drying of zirconia colourants improves zirconia brightness and increases the optical properties of the enamel.

• Journal of Animal Science and Technology
• /
• v.44 no.1
• /
• pp.45-54
• /
• 2002

This study was conducted to evaluate the feeding value of ascidian tunic shell the effects of its dietary supplementation on laying performance, egg-yolk pigmentation, egg-shell strength and egg taurine content. A total of 168 brown layers at the age of 29wks in commercial cage were fed for 4 wks with 7 different diets containing ascidian tunic shel1(AST) at varying levels of 0$\sim$5% Dm or 0% AST with 100ppm carophyll red. No differences were found in egg production and weight among the treatments indicating that ascidian tunic shell did not adversely affect the laying performances. Adding the ascidian tunic shell to the diets increased egg-yolk pigmentation compared to the control and resulted in simillar or better effect on egg-yolk pigmentation compared to 100ppm carophyll red. The data suggest that ascidian tunic shell may be used as feed ingredients in layer diet enrichment of egg-yolk pigmentation in the place of carophyll red(chemical pigment). Specific gravity and breaking strength of egg shell were significantly increased by the adding ascidian tunic shell to the diet, suggesting that ascidian tunic shell may be used as feed ingredients for increasing egg shell strength. Also taurine content of egg was significantly increased with increasing supplementation of ascidian tunic shell to the diet(p<0.05). Therefore, ascidian tunic shell may be used as feed ingredients in laying hen diet to improve egg quality such as egg-yolk pigmentation, egg-shell strength and egg taurine enrichment.

• Journal of Bio-Environment Control
• /
• v.10 no.2
• /
• pp.111-117
• /
• 2001

This experiment was conducted to elucidate the effects of foliar application of monopotassium phosphate on the acceleration of ind color and fruit quality of Satsuma mandarin cultivated in the plastic greenhouse. The 'a'value of peel chromaticity increased seasonably with the increasing frequency of foliar application of monopotassium phosphate, but became gradually irresponsive as the fruit approached to harvesting time. Glucose content increased with the number of foliar applications so did the fructose content. Content of reducing sugars tended to increase with the number of foliar applications by 0.32 to 0.41%.mL$^{-1}$ juice in treatment sof ive or more applications. Sucrose content increased gradually with the increasing number of foliar applications, but there was no significatn difference among treatments. Total sugar also increased with the increasing number of foliar applications Generally, the soluble solid level is considered to be representative of fruit quality. Sugar content increased with the number of foliar application up to 5 times in which sugar content increased by 0.93$^{\circ}$Bx as compared to the control. The fruit acidity of the treatment plots decreased as compared to that of the control, but there was no significant difference in fruit acidity among foliar application times.

• Journal of Conservation Science
• /
• v.33 no.2
• /
• pp.131-147
• /
• 2017

The purpose of this study is to analyze the characteristics of Punchong and Whiteware pottery excavated from the kiln site in Dongkok-Town, Gimge. Scientific analysis is carried out to evaluate the physical and chemical properties of the body and glaze. The physical properties indicate the gradual development of the production technology with respect to the kiln operating conditions and period. In chemical properties, the ceramic body is found to be made of raw materials from the same source, but the mixing method depends on the type of Punchong and Whiteware pottery, the production kiln, and period. Whiteware pottery is manufactured with less over 1.3% of the colorant content and more about 1.2% of the $K_2O$ flux content than Punchong pottery. This compositions allow easier vitrification at the same temperature. These characteristics which is low colorant content and high flux content become more prominent as lately. The ceramic glaze is likely to have changed the type of raw materials used after 16~17C, as the contents of MgO, $TiO_2$, MnO, $P_2O_5$ are less three to ten times than 15C.

• Journal of Conservation Science
• /
• v.36 no.5
• /
• pp.405-420
• /
• 2020

A convergence research was conducted on glass beads excavated at the ruins of Hapgang-ri, Sejong, using the archeology and conservation approach. The period of appearance of Jugu Towangmyo in the ruins of Hapgang-ri can be estimated to begin in the late 2^nd century; for Jugu Towangmyo No. 15, the period spans from the late 2^nd to early 3^rd century. Form, color, and manufacturing techniques of complete glass beads were examined, and the cross-sections and chemical composition of 16 samples were observed. Based on these analyses, the glass beads were divided into blue, purple, and red colors. The blue-colored beads could be further sub-divided based on their gloss and brightness; in contrast, the red-colored beads were highly uniform with regard to these parameters. Based on the stripe and bubble arrangement on the surface of the glass beads, their drawing technique was identified. Traces of heat treatment or polishing were observed at the ends of the beads. According to their chemical composition, the 16 samples were classified into 3 potash glass and 13 soda glass groups; in the latter, the properties of the stabilizers were divided according to the blue and red bead colors. The stabilizers of the red beads are unique in that they allow the distinction among beads excavated in other areas in South Korea owing to their compositional differences. Colorants in blue- and red-colored beads are cobalt (containing MnO), and copper and iron, respectively.

• Journal of Conservation Science
• /
• v.37 no.3
• /
• pp.232-244
• /
• 2021

This study examined the physical attributes and heat treatment characteristics of glass beads excavated from the Gimhae area, which is the location of Geumgwan Gaya. This enabled classification of surface characteristics of the beads based on the investigation of the color, size, and shape. The glass beads were classified into eight color systems, with purplish-blue beads as the representative color. Bead size was categorized into three types depending on the outer diameter and how it increased over time. Bead shapes were categorized as round, tubular, or doughnut-shaped based on the inner diameter and length, with round being the typical shape. According to the degree of heat treatment, there are three types of cross-section for glass beads that are manufactured by the drawing technique, most of which are the HT-III type. In addition, it is estimated that the heat treatment technology has more considerable effects than other methods. Through non-destructive analysis, the chemical composition was obtained and categorized as flux, stabilizer, and colorant. Analysis confirmed the presence of 63 and 9 pieces in the potash and soda glass groups, respectively. Overall findings from the study highlighted a correlation between the chemical composition and the external factors such as color, size, shape, and manufacturing technology of glass beads recovered from Geumgwan Gaya, revealing characteristics related to that time and region.

• Korean Journal of Food Science and Technology
• /
• v.3 no.1
• /
• pp.6-14
• /
• 1971

Crystalline Mucor rennin and Mucor rennet from Mucor pusillus var. Lindt was compared with Hansen's calf rennet in its properties as a milk clotting enzyme. The method of Gouda type cheese from domestic milk was established by using of Crystalline Mucor rennin and Mucor rennet. The cheese produced by using of Mucor rennet as a milk clotting enzyme sometimes had bitter taste, it can be reduced with using Crystalline Mucor rennin, instead of Mucor rennet. It was also found out that these cheeses could be colored by the pigment from Cape Jasmine which is wildly ubiquitous in Korea.

• Journal of Bio-Environment Control
• /
• v.25 no.4
• /
• pp.240-248
• /
• 2016

The objective of this study was to determine the effect of exogenous abscisic acid (ABA) on the red coloration and endogenous ABA contents of apple fruit skins. ABA and fluridone (an ABA synthetic inhibitor, FD) was sprayed on 'Hongro' apple fruit skins at 107 days after full bloom (DAFB). Visual coloration and hunter's color values were not affected by the ABA and FD treatments. Anthocyanin contents in fruit skins increased similarly to hunter $a^*$ values of fruit skins, but ABA and FD did not affect its accumulations. Liquid chromatography analysis revealed that endogenous ABA contents in control fruit increased at first and then decreased from 12 hours after the treatment. ABA treatment increased ABA contents in fruit skins from 2 hour after the treatment and it lasted until the end of the treatments. FD decreased ABA contents in fruit skins from 6 hours after the treatment. ABA treatment increased MdNCED2 (an ABA biosynthetic gene), MdACO1 (an ethylene biosynthetic gene), and MdCHS and MdDFR expressions. However, MdUFGT expressions were not affected by ABA treatment.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.1 no.3
• /
• pp.181-188
• /
• 2013

This paper is to investigate experimentally an effect of carbon amino silica black-superplasticizer(CASB-SP)on the engineering properties and chromaticity of black color concrete with 0.45 of W/C(water to cement). CASB-SP and carbon black were applied for pigment of the concrete. To prevent efflorescence of concrete, four different water repellent agents were also applied. As results, it was found that use of CASB-SP increased the slump and air contents. Furthermore, the use of CASB-SP increased the compressive strength. As CASB-SP dosages increased, chromaticity was well developed. For the effect of water repellent agent, the use of epoxy type was effective for protection from efflorescence. Based on test results, it was evaluated that 0.5% of CASB-SP effectively improve the concrete quality as well as enhance the chromaticity with proper dosage.

• Journal of Korean Ophthalmic Optics Society
• /
• v.13 no.3
• /
• pp.7-12
• /
• 2008

Purpose: To evaluate ultraviolet (UV) blocking characteristics of transparent and tinted ophthalmic lenses. Methods: The transmittance spectra of ophthalmic lenses were measured using the method suggested in ANSI Z80.1 standard. Transmittance percentage were calculated for each lens for UV (200~380 nm; UVA, UVB, UVC) and blue light portions (380~400 nm) of spectrum. Results: The results indicate that transparent plastic lenses with middle, high refractive index and tinted plastic lenses had superior UV blocking characteristics at UV radiation while UV blocker-untreated lenses such as crown glasses and CR39 did not. All except high refractive index lenses and anti-glare night vision lens was not effectively blocked blue light. Conclusions: Crown glass and CR39 lenses need to treat UV blockers to protect eyes from UV. Also, all lenes except high refractive index lenses and anti-glare night vision lens need to treat blue light blockers for protecting from blue light.