• Horticultural Science & Technology
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• v.29 no.1
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• pp.61-67
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• 2011

Barley (Hordeum vulgare L.) sprouts are a vegetable commonly used as a functional food material due to its high vitamin C concentration and antioxidant activity. In this experiment, we measured the changes in the antioxidant activity of several barley cultivars as well as in the concentrations of related compounds such as ascorbate and glutathione upon treatment with UV-B or salicylic acid (SA). The six barely cultivars were grown in a plant growth chamber (25/$18^{\circ}C$, 14/10 h, 200 ${\mu}mol{\cdot}m^{-1}{\cdot}s^{-1}$, 70% relative humidity) for 10 days. All barely cultivars showed different 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activities, which were increased by UV-B treatment and not by SA treatment. The changes in ascorbate concentrations were correlated with DPPH scavenging activity in both the treatments, suggesting that the antioxidant activity in barley sprouts was mainly dependent on ascorbate concentration. Furthermore, changes in ascorbate concentration showed similar tendencies to changes in free sugar concentration, especially glucose and sucrose, in both treatments. On the other hand, the concentrations of glutathione and cysteine highly increased by SA treatment, representing different tendencies compared to the DPPH scavenging activity and ascorbate concentration. 'Donghanchal' cultivar showed comparatively higher antioxidant activity, both constitutively and inducingly by UV-B treatment, with its higher concentrations of ascorbate and glutathione. These results suggest that barley sprouts could be used as a health-functional vegetable, contributing to the overall supply of antioxidant and sulfur-containing organic compounds.

• The Korean Journal of Food And Nutrition
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• v.34 no.6
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• pp.662-668
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• 2021

Aster koraiensis Nakai (A. koraiensis) which has been used as a food and medicinal plant in the past, is valuable as functional food material. Therefore, the aim of this study was to determine the antioxidant properties and major phenolics of A. koraiensis extracts with different ethanol concentrations (0, 50, 70, and 100% aqueous ethanol solution). When ethanol concentration in the extraction solvent was increased, extraction yield decreased; 34.2, 23.2, 21.0, and 5.5% in 0, 50, 70, and 100% ethanolic extracts, respectively. Total phenolics content and antioxidant activities of extracts were increased in an ethanol concentration-dependant manner. The major phenolics in the extracts were chlorogenic acid (21.264~58.666 mg/g), isochlorogenic acid A (10.432~145.353 mg/g), and isochlorogenic acid C(0.239~13.148 mg/g), and these phenolic contents were higher in 70 and 100% ethanolic extracts than other extracts. Significant correlations were observed between ethanol concentration of extraction solvent, antioxidant properties, and major phenolics. These results indicated that the optimal ethanol concentration for extraction was 70%.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4B
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• pp.421-426
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• 2006

The effect of initial concentration of ammonium ion ($N_0$) and active nitrifiers ($X_0$) on nitrification was examined by continuous monitoring of the ammonium removal rate. The concentration of the active nitrifiers in the culture sludge, measured by the oxygen uptake rate (OUR), was found to be 42.8% of the culture sludge. Experiments were carried out under different ratios of $N_0/X_0$, viz., 0.025 to 0.493. The results from this study show that the oxidation rate was similar under the same $N_0/X_0$ ratio despite different initial concentration of ammonium ion ($N_0$) and active nitrifiers ($X_0$). Moreover, the Contois kinetic expression which includes biomass concentration, was found to describe the mechanism behind nitrification process. The ammonium oxidation rate ($q_{Nmax}$) and half saturation constant per unit activated nitrifiers ($K_N{^{\prime}}$) were theoretically determined using the Contois expression. These values were found to be 4.32 gN/gVSS/day and 0.013 gN/gVSS respectively.

• Membrane and Water Treatment
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• v.11 no.3
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• pp.217-222
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• 2020

An electrochemical oxidation process was applied to remove cyanide (CN^-) from real plating wastewater. CN^- removal efficiencies were investigated under various operating factors: current density and electrolyte concentration. Electrolyte concentration positively affected the removal of both CN^- and Chemical Oxygen Demand (COD). As the electrolyte concentration increased from 302 to 2,077 mg Cl^-/L, removal efficiency of CN^- and COD increased from 49.07% to 98.30% and from 23.53% to 49.50%, respectively, at 10 mA/㎠. Current density affected the removal efficiency in a different way. As current density increased at a fixed electrolyte concentration, CN^- removal efficiency increased while COD removal efficiency decreased, this is probably due to lowered current efficiency caused by water electrolysis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.6 no.4
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• pp.367-376
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• 1982

Stress concentration mainly occurs near holes and notches. Then local stress is larger than nominal stress. It is necessary that stress concentration phenomena are studied because it can act as a cause of fracture of material. In order to analyze fracture of material including holes, stress concentration factor and stress distribution must be studied more carefully. In this paper the stress concentration and distribution of a slotted plate is examined. Hardened 7:3 brass plate with 4 different slots including a circular hole is used. And ratios of slot length to its root radius are 1, 2, 3, 24, 4. The stress distribution is measured by using strain gages attached to the plate with variable width. And obtained experimental data are adjusted by using calibrated gage factor.

• Journal of Environmental Science International
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• v.6 no.2
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• pp.113-124
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• 1997

The basic mechanism of the granular sludge formation which is the most important factor in the start-up and stable operators is not confirmed yet. In this study, the effect of granular sludge formation was investigated with the different substrate concentrations and the various ratios of substrate supply/deficiency. The granular sludge formation in the UASB reactor was closely related to the substrate concentrations and the ratio of substrate supply/deficlency The granular sludge formation was not accelerated at low substrate concentration. It was convinced that granular sludge formation was accelerated when the substrate supply with high concentration was stopped at UASB reactor. From this experiment, it was estimated that granular sludge was formed by the combination of hydrogen utilizing bacteria that form hydrogen condition and acid forming bacteria at substrate deficit condition by mutual symbiosis. Though the removal efficiency of organic matter was decreased as the influent substrate concentration was Increased, the higher the influent substrate the better the granular sludge formation.

• Macromolecular Research
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• v.11 no.6
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• pp.467-470
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• 2003

The dielectrophoretic technique was used to prepare density gradient polymers, polystyrene doped with a dipolar modifier, diphenyl sulfide. We have measured concentration gradients of the dopant by UV/Nis spectroscopy as a function of time in a nonuniform electric field. Measured concentration data at different positions of the sample confirmed that a concentration gradient arose after a nonuniform electric field was applied to the system, these data were used to compare the concentration profile with that predicted by the dielectrophoresis equation.

• The Korean Journal of Food And Nutrition
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• v.14 no.3
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• pp.222-227
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• 2001

The production results of the oriental functional beverage, which is aimed at reducing the alcohol concentration in blood, are as follows. Different kinds of herb medicine ingredients were combined to achieve the balance between Yin And Yang. They were grouped according to their respective characteristics and extracted by heat, Then they were combined and produced following the most effective mixture ratio. The drink produced by this way consisted mainly of water, Sugar, mineral, protein and fiber were partially contained. Among the minerals, the proportion of calcium, potassium, magnesium was high and iron was also contained. This drink turned out to be effective in reducing the alcohol concentration in blood within a very short time when it was taken once after drinking and taken aging 30 minutes later, which would double the dosage. This result shows that development of such a functional beverage using the herbal medicine, At the same time it will play an important part in reducing the alcohol concentrate in blood after drinking liquors.

• 한국가시화정보학회:학술대회논문집
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• 2005.12a
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• pp.1-5
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• 2005

The digital HPTV velocity field measurement consists of four steps: recording, numerical reconstruction, particle extraction and velocity extraction. In the velocity extraction process, we improved PTV algorithm to extract the displacement of particle each placed in 3D space. Because a digital recording device was used, some factors such as a spatial resolution, numerical aperture, and particle concentration can affect the performance of the digital HPTV. Especially, a particle concentration ($C_{o}$) affected tile reconstruction efficiency in numerical reconstruction and particle extraction process. In this paper, the reconstruction efficiency was analyzed experimentally with different particle concentration. Optimal reconstruction efficiency was shown in the range of $C_{o}$=$13\∼15$ particles/$mm^{3}$.

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.4
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• pp.59-66
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• 2011

This study aims to understand the degree of inequality of surveyed rural amenity resources according to resources and region in basic self governing body by estimating the Gini Coefficient and Lorenz Curve. Case Study was performed in Sunchang basic self governing body which full survey of rural amenity resources was completed. The Gini Coefficient was applied to measure the concentration of amenity resources in 11 Eup-Myun regions, Sunchang county of Jeonbuk province. The results demonstrate significantly different variation according to Eup-Myun regions and amenity variables. This result would be used as a basic data for rational rural planning based on amenity resources through identifying distributional concentration of rural amenity resources in basic self governing body.