• Journal of Technologic Dentistry
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• v.34 no.2
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• pp.129-134
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• 2012

Purpose: This study was conducted to investigate the colors of zirconia and veneered ceramics according to the build-up method of veneer porcelain. Methods: The samples were divided into three groups: a group for which a liner was applied to the zirconia surface and dentine coating was built up and burned (Cz1), a group for which the dentine coating was directly built up and burned (Cz2), and a group for which the samples were wash-burned with dentine coating and a dentine coating was built up and burned again (Cz3). The the colors were measured with a Spectrophoto-meter. Results: The average $L^*$ value of the Cz3 group was the highest among the groups at $59.1{\pm}0.5$ (P<0.05), followed by Cz2 at $57.5{\pm}0.8$ and Cz1 at $56.6{\pm}1.3$. The $a^*$ value of Cz3 was negative at $-0.0{\pm}0.0$ and the $a^*$ values of Cz2 and Cz1 were positive at $0.2{\pm}0.1$ and $0.4{\pm}0.0$, respectively (P<0.05). The $b^*$ of Cz1 was the highest at $11.2{\pm}0.6$, followed by Cz3 at $10.8{\pm}0.5$ and Cz2 at $10.5{\pm}0.8$ (P<0.05). Conclusion: Compared to other experimental groups, the Cz3 groups showed the brightest colors with high brightness and relatively low green and yellow levels.

• The Korean Journal of Ecology
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• v.6 no.4
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• pp.257-260
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• 1983

The concentration of heavy metals in 12 eggs collected from 6 nests of Intermediate Egret, Egretta intermedia intermedia from Ogjong-myun, Hadong-gun, Kyungnam, was examined by atomic absorption spectrophoto-meter method in 1983. It was found that heavy metals are contained in their eggs with highest concentration Cd and Cu in the eggshell and Cr, Zn, Pb and Mn in the yolk, respectively. The thin-shelled group, by their eggshell thickness grouping, contained heavy metal in higher amount than that of thick eggshelled group. And the thin group showed small values in weight of individual egg, its yolk and albumen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.5
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• pp.418-428
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• 1990

This study measured each daily intake and excretion of iron copper and cobalt of eight 20-26 years old college men during four weeks by means of analyzing their food intake urine and feces keeping their normal living pattern and maintenance body weight. This study also compared the actual measurement value of iron intake by atomic absorption spectrophoto-meter with the conversion value of it by food table. The results were as follows. Each person's average intake daily was iron 9.19±0.32mg/day, copper 0.56±0.06mg/day and cobalt 1.86±0.18mg/day. Each person's average urinary excretion daily was iron 0.53±0.07mg/day, copper 0.07±0.03mg/day and cobalt 0.13±0.01mg/day. Each person's average fecal excretion daily was iron 1.73±0.14mg/day copper 0.16±0.01mg/day and cobalt 0.46±0.08mg/day. The actual measurement value was 9.19±0.32mg/day and its conversion value 14.07±0.29mg/day : the former was 35% lower than the latter.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.162-167
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• 2006

Nanofluid is a kind of new engineering material consisting of nanoparticles dispersed in base fluid. Nanofluids could have various applications such as magnetic fluids, heat exchanger working fluids, lubricants, drug delivery and so on in present study, various nanoparticles, such as MWCNT (Multi-walled Carbon Nanotube), fullerene, copper oxide, and silicon dioxide are used to produce nanofluids. As base fluids, DI-water, ethylene glycol, oil, and silicon oil are used. To investigate the thermo-physical properties of nanofluids, thermal conductivity and kinematic viscosity are measured. Stability estimation of nanofluid is conducted with UV-vis spectrophoto-meter. In this study, the high pressure homogenizer is the most effective method to produce nanofluid with the prepared nanoparticle and base fluid. Excellently stable nanofluids are produced with the magnetron sputtering system. Thermal conductivity of nanofluid increases with increasing particle volume fraction except water-based fullerene nanofluid which has lower thermal conductivity than base fluid due to its lower thermal conductivity, 0.4 W/mK. The experimental results can't be predicted by Jang and Choi model.

• Applied Biological Chemistry
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• v.3
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• pp.1-7
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• 1962

In order to study the rate control step in the protein metabolic course of the chlorophyll formation, the transaminase activities which are obtained freely in the extracts of cotyledons of germinating peas at the light and the dark places, are measured in Beckman mopel D.U, spectrophoto meter at 490 mu. In this case, of two enzymatic reaction products; oxalacetic acid and pyruvic acid, the former is converted to pyruvic acid by aniline citrate and after each pyruvate phenyl hydrazones are extracted by toluenes: when this is treated with strong alcoholic alkali, a colored hydrazone is formed and it is measured by above apparatus. The estimated G.O.T. and G.P.T. in the germinated cotyledons at dark and light places considerably differ in their activities; G.O.T. and G.P.T. activities which are formed at the light are more increased than at the dark and also they differ in their rates through germination, though G.O.T. activity increment is smoothly but that of G.P.T. is more sharply, and they are considered to be directly affected to the chlorophyll formation and indirectly to the growth. G.O.T. and G.P.T. in each fractions of cell in the cotyledons should be formed by dissociation of zymogens in the microsomal fractions and it seems to promoted by light. In the formation of the chlorophyll, the protein metabolism occurred mainly in the microsomal fractions and the rate determining step is found at the point where the zymogene that is able to produce G.P.T. is activated, and this activation is promoted by light as noted above.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.123-130
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• 2005

High salt concentrations in the ginseng nursery soil environment of Korea is one of important reducing factors for the stable production of quality ginseng. These studies were accomplished for check the response on germination of ginseng seed, somatic embryogenesis of zygotic embryo, and biosynthesis of ginsenoside from ginseng hairy root against NaCl. Ratio of germination was at the $3\%\;and\;84.5\%$ on the basic media with 0.1M and free of NaCl repectedly, but $0\%$ at the upper of 0.2M NaCl. Somatic embryogenesis from zygotic embryo were the highest when immatured embryo was cultured on free of NaCl concentration, and which was intend to decrease at treatment of NaCl. However, in case of using the matured embryo, treatment of 0.05M NaCl resulted in better embryogenesis than NaCl free media. Red pigment was synthesized from ginseng hairy root cultured on the medium with various NaCl concentration(from 0.04 to 0.08M) and its pigment was analyzed as spectrum of anthocyane by spectrophoto- meter scanning. This cell line biosynthesized lots of crude saponin and total ginsenoside than other cell lines, also had 2 times of panaxadiol than panaxatriol.