• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.5
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• pp.369-371
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• 2003

Cyanidin 3-glucoside (C3G) content contained in the grains of blackish purple rice varieties, Heugjinjubyeo, Kilimheugmi, Heugnambyeo, Sanghaehy-anghyeolla, and the progenies derived from their crosses was evaluated by HPLC and UV-Vis spectroscopy. C3G content was higher in the range of 10-30% by using UV-Vis method compared to HPLC method. A significant linear relationship was, however, observed between two analytical methods. The correlation coefficient was 0.98. Thus, this results suggested that it would be able to use UV-Vis spectroscopy to determine C3G content which does not demanded precise value like selection.

• Food Engineering Progress
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• v.15 no.3
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• pp.262-268
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• 2011

The effects of pellet moisture content on physical properties (expansion ratio, density and breaking strength) of vacuum-puffed Yukwa (non-oil puffed Yukwa) were investigated in this study. The Yukwa was made from the waxy rice steeped at 25 and $30^{\circ}C$ for 3, 5 and 10 days with pellet drying times (6, 8 and 10.5 hr). As the drying time increased from 6 to 10.5 hr at $50^{\circ}C$, the highest value of pellet moisture content (29.4%) was found in the samples made from the steeped waxy rice at $25^{\circ}C$ for 5 days after 6 hr drying, while the lowest value (16.3%) was found at $25^{\circ}C$ for 3 days after 10.5 hr drying. Both redness and yellowness values of vacuum-puffed Yukwa increased as the drying time increased. The expansion ratio of Yukwa was greatly affected by drying time, ranging from 2.07 (26.8% pellet moisture content) to 7.01 (24.0% pellet moisture content). From the data, it can be concluded that the pellet moisture content had a significant influence on the physical characteristics of vacuum-puffed Yukwa. With vacuum puffing condition of 3 min heating and 2 min puffing, the pellets with about 25% moisture content showed higher expansion ratio, and lower density and breaking strength.

• Journal of the Korean Ceramic Society
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• v.22 no.2
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• pp.25-32
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• 1985

Effect of alkali $SO_3$ and $C_2S$ content and cooling condition of clinker on the formation of unstable alkali and cooling condition of clinker on the formation of unstable alkali was investigated. As a result alkali and $SO_3$ content of clinker were the main factors of unstable alkali formation and equation (7) in which the two factors were the variables showed a good agreement with the observed results. Water soluble alkali content of sulphate was decreased with increase of $C_2S$ content of clinker resulted by the increase of solid solution rate of alkali to clinker minerals. But change of unsatble alkali content accordint to the increase of $C_2S$ content was slight. A increasing tendency of ignition loss of clinker with increase of unstable alkali content was found.

• Journal of the Korean Society for Heat Treatment
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• v.15 no.5
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• pp.219-227
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• 2002

This study has been performed to investigate the effect of $CO_2$ content on the growth characteristics of the compound layer, porous layer and corrosion characteristics of carbon steels after gaseous nitrocarburizing in $70%-NH_3-CO_2-N_2$ at $580^{\circ}C$ for 2.5 hrs. The results obtained from the experiment were the thickness of the compound and porous layers increased with increasing $CO_2$ contents. At the same fixed gas composition the thickness of the compound and porous layer increased with increasing carbon content of the specimens. X-ray diffraction analysis showed that compound layer was mainly consisted of ${\varepsilon}-Fe_{2-3}(N,C)$ and ${\gamma}^{\prime}-Fe_4N$ as the increased with $CO_2$ contents in atmosphere, compound layer was chiefly consisted of ${\varepsilon}-Fe_{2-3}(N,C)$ phase. With increasing $CO_2$ content and total flow rate in gaseous nitrocarburizing, the amount of ${\varepsilon}-Fe_{2-3}(N,C)$ phase in the compound layer was increased. The current density of passivity decreased with increasing $CO_2$ content due to the development of porous layer at the out most surface of ${\varepsilon}-Fe_{2-3}(N,C)$.

• Journal of the Korean Society for Heat Treatment
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• v.3 no.4
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• pp.23-40
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• 1990

This study has been carried out to investigate into some effects of Mn content with varying amounts and austenite grain size on hardenability in boron-added Fe-C-Cr-Mo alloy systems. (1) Austenite grains have been found to hardly grow in the temperature range of $900^{\circ}C$ to $950^{\circ}C$, whereas they grow rapidly in the temperature range of $975^{\circ}C$ to $1100^{\circ}C$. (2) Austenite grain growth is considerably small with increasing holding time at a given austenitizing temperature and is, in particular, hardly found to occur at a temperature of $900^{\circ}C$. (3) The hardenability improves ramarkably as Mn content is increased at three different austenitizing temperatures $900^{\circ}C$, $1000^{\circ}C$ and $1100^{\circ}C$. (4) The maximum hardenability is obtained from steels A, B and C austenitized at the $900^{\circ}C$, although Mn content is varied in each specimen.

• Journal of Life Science
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• v.12 no.3
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• pp.233-241
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• 2002

Seasonal variation of uraenesox cinereus) muscle was investigated. Crude lipid content varied from 3.85 to 12.59 g/100g, comprising the highest content in November. The major fatty acids of total lipid, neutral lipid, and phospholipid were C16:0, C23:0, C16:1, C18:1, C20:5, and C22:6, but in phospholipid, Cl8:3n-6 was also the major fatty acid. The C22:6 content of the neutral lipid was much lower compared to that of the total lipid and phospholipid. The content of polyunsaturated fatty acids (ranged from 73.93 to 66.23%) in phospholipid was higher than that of any other lipid fraction. In glycolipid, C20:1 and C14:1 were higher compared to those of any other lipid fraction, but C20:5 and C22:6 were lower. The annual average ratio of n-3 to n-6 of total lipid, neutral lipid, phospholipid, and glycolipid was 10.82, 12.27, 6.63, and 6.50, respectively. The particular trend of seasonal variation of fatty acid composition was not showed in total and neutral lipid. However, the samples caught in September and November had a high crude lipid content with a significantly lower content of polyunsaturated fatty acids in phospholipid. Also, the content of monounsaturated fatty acids in glycolipid was lower in samples of September, November, and January.

• Journal of the Korean Home Economics Association
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• v.19 no.3
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• pp.41-45
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• 1981

This study was carried out to observe the changes of Vitamin C content and to preserve the quality for the circulation periods of hot green pepper fruits wrapped with polyethylene film under the indoor temperature, as well as to find the proper time for harvest of hot green pepper fruits as a hot taste food and vegetable. the results obstained were as follows: 1. The consignment rate of hot green pepper fruits was highest, 60.2% on the 25th day after flowering, the nest 25.4% on the 20 th day, 10.3% on the 30th day and 4.1% on the 35th day. 2. the content of Vitamin C I each pepper fruits was highest o the 30th day, considerably high on the 25th day and 20th day. 3. The total content of Vitamin C in each part of hot green pepper fruits; the content in pericarp was much higher than in placenta and seed, and that of hydro type Vitamin C was almost the same. 4. The reduction rate of vitamin C during circulation periods was highest on the 3rd day; 42% in pericarp, 50% in placenta, 65% in seed. But in the package wrapped up with polyethylene film, the reduction rate in the same period was 5% in pericarp, which was very low in reduction, and those in placenta and seed were almost the same as in the unwrapped state.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.315-320
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• 2006

A precision test of hydrometer method, used to determine soil texture, was conducted on selected 10 soil samples, compared to pipette method. Soil texture measurements with hydrometer method were performed with monitoring the temperature of soil suspension in settling cylinder. The temperature and its fluctuation during settling time had a range of $13^{\circ}C-28^{\circ}C$ and $0.2^{\circ}C-4.4^{\circ}C$, respectively. The difference of clay content between hydrometer and pipette method were distributed from -6.4% to 4.0%. Positive end of difference in clay content was observed at soil having very low clay content, whereas negative end at soil having high organic matter content and exchangeable cations. Except both ends, difference in clay content of soils was less than 3%, and expecially closed to 0% in soils having clay content more than 25%. The difference of sand content were distributed from -1.5% to 4.2%. Similar to clay content, positive end soil was soil sample having lowest sand content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1543-1549
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• 2015

Black rice bran, a by-product from rice milling process, is a good natural source of anthocyanin pigment. The purpose of this study was to determine the optimum conditions for anthocyanin extraction from black rice bran as well as the stability of anthocyanin extract according to different storage temperatures. The main anthocyanin in 'Heugkwang' rice bran was identified as cyanidine-3-glucoside (C3G) by HPLC and LC-MS/MS. The yield and C3G content of black rice bran extract were investigated with various extraction solvents, temperatures, and times. The results indicate that the optimum extraction solvent, temperature, and time were 50% ethanol, $70^{\circ}C$, and 2 h, respectively. The stability of anthocyanin extract was studied during a storage period of 168 days at various temperatures ($-20^{\circ}C$, $4^{\circ}C$, and room temperature). Hunter's values (L, a, and b) of anthocyanin extract increased, whereas C3G content continuously decreased up to 168 days. Variations in Hunter's values and C3G content become larger as storage temperature increased. Anthocyanin extract from black rice bran was very stable, as C3G content after storage at all temperatures was maintained at more than 90% of initial content. These results suggest that anthocyanin extract from black rice bran may be useful as a natural food colorant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.spc
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• pp.58-64
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• 2008

A complete diallel cross was performed to determine the inheritance of 1,000 grain weight of brown rice and cyanidin-3-glucoside (C3G) content and combining ability of five pigmented rice that showed different level of C3G content. Parents and F1 of 20 crosses were evaluated for 1,000 grain weight of brown rice and C3G content which extracted from pigmented rice grain with 0.1% trifluoroacteic acid (TFA) in 95% EtOH. For 1,000 grain weight of brown rice and C3G content, both additive and dominant gene effects were detected and the dominance was partial and there were more dominant alleles than recessive ones. Genetic parameters pointed out that there are significant additive and dominant effects and the additive effect is bigger than the dominant one for both grain weight and C3G content. The frequency of negative alleles were higher than positive alleles. Narrow sense heritability estimates were 0.66 for grain weight of 1,000 brown rice and 0.70 for C3G contents. General combining ability (GCA) effects and specific combining ability (SCA) effects were highly significant and GCA effects were drastically higher than SCA ones. It indicates that the inheritance of the C3G contents is controlled mainly by additive genetic factor.