• Transactions of the Korean hydrogen and new energy society
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• v.15 no.1
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• pp.23-31
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• 2004

For the fabrication of high efficient bifunctional electrocatalyst of oxygen electrode for PEM URFC (Polymer Electrolyte Membrane Unitized Regenerative Fuel Cell), which is a promising energy storage and conversion system using hydrogen as the energy medium, several bifunctional electrocatalysts were prepared and tested in a single cell URFC system. The catalysts for oxygen electrode revealed fuel cell performance in the order of Pt black > PtIr > PtRuOx > PtRu ~ PtRuIr > PtIrOx, whereas water electrolysis performance in the order of PtIr ~ PtIrOx > PtRu > PtRuIr > PtRuOx ~ Pt black. Considering both reaction modes PtIr was the most effective elctrocatalyst for oxygen electrode of present PEM URFC system. In addition, the water electrolysis performance was significantly improved when Ir or IrOx was added to Pt black just 1 wt.% without the decrease of fuel cell performance. Based on the catalyst screening and the optimization of catalyst composition and loading, the optimum catalyst electrodes for PEM URFC were $1.0mg/cm^2$ of Pt black as hydrogen electrode and $2.0mg/cm^2$ of PtIr (99:1) as oxygen electrode.

• Journal of the Korean Ceramic Society
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• v.26 no.5
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• pp.609-616
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• 1989

For the development of high durable portland cement, it was tested that the some physical properties of ordinary portland cements (OPC) treated with 0.3-1.5wt.% asphalt and 0.5-1.0wt.% carbon black. From the results, the contact angles of water against cements treated with more than 0.6wt.% asphalt were increased over 80 degrees, the initial and the final setting times of cement paste were delayed about 20min. according to the every 0.3wt.% increase of asphalt. The first and the second pick heights of the hydration curve of the cement were considerabely decreased and the induction period of that was increased. And so, the cumulative hydration heat of the cement which was treated with 0.6wt.% asphalt and 0.5wt.% carbon black was lower about 10cal/g than that of ordinary portland cement during 42 hydration times.

• Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.278-283
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• 2010

Black plaice, Pleuronectes obscurus (Herzenstein), were collected and fertilized to observe egg development, temperature-related cleavage rates, and mitotic intervals (${\tau}_0$). Fertilized egg was demersal, adhesive, and did not contain oil globules. After 1.75 h, the blastodisc formed, and hatching took place 121 h after fertilization at $14^{\circ}C$. The hatched larvae were $3.5{\pm}0.16\;mm$ in total length. At higher temperatures, eggs developed faster and underwent further identical developmental processes. Additionally, ${\tau}_0$ and water temperature were strongly negatively correlated at all temperatures (Y=-2.6981X+98.767, $R^2$=0.9831, where Y is ${\tau}_0$, and X is temperature) for black plaice.

• Journal of the Korean Home Economics Association
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• v.30 no.3
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• pp.119-129
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• 1992

Black soybeans were gamma-irradiated at dost levels of 0, 2., 5, 10 and 20 kGy, and stored at room temperature for the experiments associated with cooking quality. The degree of cooking of soybeans in boiling water at 98-10$0^{\circ}C$ has been determined by measuring the maximum cutting force of cotyledon. The cutting force to reach a complete cooking was about 120~130g/g. Irradiation at 2.5~20kGy caused the reduction of cooking time in black soybeans by 30~60% compared to the nonirradiated control, and the cooking rate constant of the irradiated samples was higher than that fo the nonirradiated control sample. These results were similarly found in the stored samples for one year at room temperature after irradiation. Color characteristics of cooked samples showed no significant difference between the nonirradiated control and 5 kGy-irradiated sample. After complete cooking of black soybeans, there were not significant in the organoleptic qualities between the nonirradiated and irradiated samples.

• Culinary science and hospitality research
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• v.12 no.4 s.31
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• pp.236-246
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• 2006

The different rheological properties of wheat flour and waxy black rice flour dough were investigated in dough with 10, 20, 30 and 40% of waxy black rice flour(WBRF). Water absorption and weakness of dough was increased, but stability of dough, high initial pasting temperature, viscosity at peak point and the volume were decreased after 2nd fermentation as the addition of WBRF was increased. In the 10% addition of WBRF, the dough showed similar rheological properties with those of control group.

• Natural Product Sciences
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• v.13 no.4
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• pp.373-377
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• 2007

Antiscratching behavioral effects of the water extract of two black colored rice (BCR) varieties [Oryza sativa L. cv. Heugjinjubyeo (HJ) and Josaengheugchalbyeo (JH)], major pigment of which is cyanindin 3-glucoside, were investigated. Orally administered BCRs' extracts exhibited potent inhibitory activity against scratching behaviors which were induced by compound 48/80 and histamine. The inhibitory effect of Josaengheugchalbyeo in vivo and in vitro were more potent than those of Heugjinjubyeo. These finding suggest that black colored rice, especially Josaengheugchalbyeo, may inhibit scratching behaviors and anaphylaxis reaction by stabilizing membrane.

• Journal of Ginseng Research
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• v.6 no.1
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• pp.30-37
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• 1982

This study was conducted to investigate the water vapor permeability of packaging film, Al- foil laminated paper, and sorption properties of dehydrated and powdered foods. The results are as fellows. 1. Absorption rate of each products was greately affeoted by physicochemical properties of foods rather than initial moisture contents of the products. 2. The absorption rate of each products were in the order of freeze dried coffee, spray dried coffee, freeze drie4 ginseng extract, spray dried ginseng extract, ginger tea, black tea, citrus juice Powder and ssang wha tea. 3. Most of the products such as freeze dried coffee, spray dried coffee, freeze dried ginseng extract, ginger tea and black tea have shorter than a month of shelf life. 4. The stability of the products were greatly affected by its desorption properties than the degree of desorption of moisture. 5. Water vapor permeability of packaging materials which are laminated Al-foil with polythylene and glassin paper were mainly affected of thickness of Al-foil and polyethylene.

• Food Science of Animal Resources
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• v.43 no.1
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• pp.61-72
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• 2023

The practical use of Korean native black goat skin as a source of gelatin extraction is limited. The objective of this study was to optimize the extraction temperature and time of gelatin from Korean native black goat skin, and to compare the quality characteristics of goat skin gelatin and other commercial gelatin products. Response surface methodology was applied to optimize the extraction temperature and time of gelatin obtained from native Korean black goat skin. The effects of temperature (50℃-70℃) and time (2-4 h) on extraction yield and gel strength were investigated using a face-centered central composite design with 13 experiments. Gelatin extraction from Korean native black goat skin was prepared through the serial processes of alkali pre-treatment, bleaching, neutralization, hot-water extraction, and freeze-drying. Using the optimization plot of Minitab software, the optimized conditions for extracting temperature and time of goat skin gelatin were 59.49℃ and 3.03 h, and the optimized values of extraction yield and gel strength were 12.52% and 263.37 g, respectively. Based on a quality comparison of goat skin gelatin with commercial gelatin, the pH value of gelatin extracted from Korean native black goat skin was 5.57. The color of gelatin extracted from Korean native black goat skin was darker than that of commercial gelatin (p<0.05). Higher emulsifying properties and gel strength of goat skin gelatin were observed when compared to those of commercial gelatin (p<0.05). Therefore, the results of this study indicate that Korean native black goat skin may be a valuable source for gelatin extraction.

• Journal of the Speleological Society of Korea
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• no.61
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• pp.5-16
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• 2000

Recently many environmental researcher are concerned about the ecological environment and the issue of environmental pollution in cave. In this paper we discuss about air pollution, water pollution, state of water quality, ecological environment and situation of environmental public damage in cave The concerning of air pollution in cave is mainly to the type of secondary contamination, which much is developed in various fields recently. The natural water in the most of cave is no problems but ground water has slitting with natural water during much raining period. The state of water quality is gradually contaminated with artificial environmental pollution, that is, the contents of kinds of Aluminum, Nickel, Copper, Zinc and Calcium are higher than before. On the other hand it is very important things to keep the control of constant temperature, darkness and humidity in cave. The contamination by lamp flora and even black colored contamination are appeared nowadays. The ecological environment in cave destructed by growing of mi coorganism. In fact the internal of cave is shielded with the state of climate of cave external but the environment of internal cave is contaminated, because blowing from external climate state. In addition to environmental pollution caused by carbon dioxide and body temperature of tourists. By the way eco-examination of cave is black color public damage, green color one and white color one has been discovered, so we need to have the situation of demand of environmental reservation alternatives.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.971-980
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• 2019

We profiled the health-promoting bioactive components in nine types of soybean seeds with different seed coat colors (yellow, green, brown, and black) and investigated the effects of different extraction solvents (methanol, ethanol, and water) on their antioxidant activities. The carotenoid and anthocyanin compositions varied greatly by seed color, and the phenolic acids, total phenol, and total flavonoid contents differed by genotype. The carotenoid content was relatively higher in soybean seeds with green and black seed coats than in those with a yellow seed coat while lutein was the most plentiful. The anthocyanin content was considerably higher in the soybean seed with the black seed coat. The results of the DPPH assay showed strong antioxidative activities in the methanol- and water-extracts compared to the ethanol-extract, irrespective of the seed coat colors. Moreover, the soybean seeds with the black seed coat exhibited the highest antioxidant activity among the samples, regardless of the extraction solvent used. Eighteen bioactive compounds were subjected to data-mining processes including principal component analysis and hierarchical clustering analysis. Multivariate analyses showed that brown and black seeds were distinct from the yellow and green seeds in terms of the levels of carotenoids and anthocyanins, respectively. These results help our understanding of the compositional differences in the bioactive components among soybean seeds of various colors, providing valuable information for future breeding programs that seek to enhance the levels of compounds with health benefits.