• Food Science and Biotechnology
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• v.18 no.6
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• pp.1476-1480
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• 2009

Antioxidant activities of mulberry leaf extracted with different concentrations of EtOH were investigated. Total phenolic content and electron donating abilities of extract from 70% EtOH were the highest. Extracts obtained from EtOH-water mixture were shown to be significantly higher superoxide dismutase (SOD)-like activities than other treatment (p<0.05). Angiotensin-converting enzyme (ACE) inhibition was the greatest at 50% EtOH concentration (p<0.05). The extracts from 30-70% EtOH exhibited higher ferric reducing ability of plasma (FRAP) value than rest of the concentration (p<0.05). In case of nitrite scavenging activity, much higher scavenging activities were observed when the extraction was performed with EtOH or EtOH-water mixture (p<0.05). The results indicate that concentration of EtOH as extraction solvents can affect the antioxidant activity of mulberry leaf, which may provide useful information on the optimal solvent conditions for the extraction.

• Solar Energy
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• v.15 no.1
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• pp.73-84
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• 1995

The present paper is on the utilization of a thermal decomposition reaction $Ca(OH)_2=CaO+H_2O$, for thermal energy storage. One of the important problems in this case is how to heat up and decompose the particle of $Ca(OH)_2$ effectively where the thermal conduction is poor. In this study, the effects of Cu-plates which are placed in the $Ca(OH)_2$ packed bed as heat transfer fins are investigated experimentally. The results show that the Cu-plates are very effective for heat transfer and the thermal decomposition in the $Ca(OH)_2$ packed bed. The amount of time to dehydrate took less than a half than that without fins under the conditions of this study.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.17-22
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• 2008

Four kinds of leaves with different shapes of leaf blade were used as experimental materials to establish an optimum condition for treating leaves to obtain skeleton leaves. Effective concentration and length of soaking time in a hot NaOH solution, which resulted in high valued ornaments, were 60% (v/v) for 50 minutes for Acer buergerianum (palmatifid), 20% (v/v) for 50 minutes for Ilex cornuta (serrate), 20-60% (v/v) for 70 minutes for Quercus mongolia (lobed), and 20-40% (v/v) for 70 minutes for Quercus palustris (parted). Through a series of the process of soaking leaves in a hot NaOH solution, rinsing or brushing to remove mesophyll, drying, and dying, high quality ornaments could be obtained.

• Applied Chemistry for Engineering
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• v.2 no.2
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• pp.127-137
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• 1991

The dissociation and partial oxidation of $CH_3OH$ on polycrystalline $MoO_3$ powder catalyst were studied using thermal desorption spectrometry(TDS) under high vacuum condition. $CH_3OH$ was dissociatively adsorbed on $MoO_3$ in the forms of surface methoxy($-OCH_3$) and atomic hydrogen(-H). $CH_3OH$ desorbed at 425 K via the re-association of methoxy and adsorbed hydrogen atom, and HCHO desorbed at 545 K through the bond breakage of C-H in methoxy. Water TDS spectra showed two desorption peaks, that is, ${\alpha}$-peak at 428 K and ${\beta}$-peak at 586 K. It was suggested that ${\alpha}$-peak was due to the hydroxyl formed on $MoO_3$ surface during the dissociation of $CH_3OH$, and that ${\beta}$-peak was from the association of lattice oxygen and surface hydrogen atom formed by the bond breakage of C-H in methoxy. Pre-adsorbed oxygen on the surface of $MoO_3$ catalyst increased the amount of adsorption of $CH_3OH$ by promoting the dissociation of $CH_3OH$ on the surface, whereas pre-adsorbed water decreased the amount of adsorption of $CH_3OH$ by blocking of adsorption sites for $CH_3OH$.

• Korean Journal of Materials Research
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• v.8 no.4
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• pp.368-374
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• 1998

The corrosion characteristics of zirconium alloys have been investigated in various aqueous solutions of LiOH. NaOH, KOH, RbOH. and CsOH at 3S$0^{\circ}C$. The concentrations of solutions were set to 4.3 mmol and 32.Smmol with equimolar $M^+$ and OH . The oxide characterization was performed using TEM on the samples corroded in 32. Smmol LiOH, NaOH, and KOH solution. The samples were prepared to have the same oxide thickness for the pretransition and post- transition regimes. Considering the trend of experimental data, the cation would playa major role in the corrosion process of Zr alloys in alkali hydroxide solutions. The microstructures of the oxides formed in various solutions were quite different. In LiOH solution the oxides grown in pre-transition as well as post-transition had the equiaxed structures with many pores and open grain boundaries. The oxides grown in NaOH solution had the protective columnar structures in pre-transition and the equiaxed structures with many open grain boundaries in post- transition. On the other hand. in KOH solution the columnar structure was maintained from pre- transition to post- transition. It was considered that the cation incorporation into zirconium oxide controlled the oxide characteristics and the corrosion acceleration in alkali hydroxide solutions.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.60.1-60.1
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• 2015

High energy photons and mechanical energy produced by the process of star formation result in copious FIR molecular and atomic lines, which are important coolants of the system. Photons thermally or mechanically induced could dissociate water in the dense envelope to change relative abundances among the species of O, OH, and H2O. Here we analyze OH emission lines toward embedded young stellar objects (YSOs) observed as part of the Herschel open time key program, 'Dust, Ice, and Gas In Time (DIGIT)' in order to study the physical conditions of associated gas and the energy budget loaded on the OH line emission. According to our analysis of the Herschel/PACS spectra, OH emission peaks at the central spaxel in most of sources, but several sources show spatially extended emission structures. In the extended emission sources, the distribution of OH emission is correlated with that of [OI] emission and extended along the outflow directions. Considering the diversity of source properties, ratios between detected OH lines are relatively constant among sources. In addition, each OH line has strong correlation with bolometric luminosity. In order to determine the physical conditions of YSOs, we adopt several methods for the analysis of the OH lines: rotational diagram, non-LTE LVG analysis, and a 2-D PDR code. From the simple LVG analysis, we find that the thermal solution with the dense ( > $10^7cm^{-3}$) and warm ( ~ 100 K) OH gas reproduces the ratios of detected OH lines. However, our self-consistent PDR 2-D model, which can deal with the IR-pumping effect from the central protostar as well as the warm dust in situ, cannot fit the observational results, suggesting that an irradiated shock model is necessary for a better interpretation.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1430-1433
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• 2004

A study was conducted to determine the effect of different alkali treatments on changes in chemical composition and on degradability of bagasse and rice straw. This study divided into 2 experiments, the first with bagasse and the second with rice straw. Each experiment comprised 9 treatments which included: untreated control; 3% NaOH; 6% NaOH; 3% urea; 6% urea; 3% NaOH/3% urea; 3% NaOH/6% urea; 6% NaOH/3% urea; 6% NaOH/6% urea. In both experiments, crude protein contents were increased from 2.0 to 12.5 units for bagasse and 3.1 to 13.7 units for rice straw by urea treatments. Ash contents of the treated bagasse and rice straw were increased over the untreated control (1.5-9.7 units for bagasse; 4.2-8.8 units for rice straw). The effects on ether extract, crude fiber, neutral detergent fiber and acid detergent fiber of the treated bagasse and rice straw were variable. Nylon bag degradability of dry matter and crude fiber were increased by treatments applying NaOH and NaOH plus urea but not urea alone. In contrast, the egradability of neutral detergent fiber and acid detergent fiber were reduced compared with the untreated control. From these degradability studies, it can be concluded that the most efficient treatments of bagasse were those treatments with 6% NaOH, followed by treatments with 6% NaOH plus 3% or 6% urea and 3% NaOH plus 3% or 6% urea, respectively. However, when comparison was made on the cost of chemical used to treat the agricultural by-products, particularly in case of rice straw, 3-6% urea would be appropriate.

• Journal of the Korean Solar Energy Society
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• v.24 no.1
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• pp.7-12
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• 2004

Mixtures type PCM, $H_2O$-NaOH that has relatively large capacity of the latent heat and long duration of phase change temperature was developed and experimentally analyzed for the low temperature storage of the food and medical products. The results could be summarized as follows; 1. Borax as nucleating agent and acrylic polymer as thickening agent were added to $H_2O$ to prevent the supercooling and phase separation. 2. Phase change (solid$\leftrightarrows$liquid) duration of $H_2O$ added with NaOH was prolonged longer 50% than that of pure $H_2O$. 3. Phase change temperature of the latent heat material, $H_2O$-NaOH was $1.5\sim2^{\circ}C$ the maximum latent Heat was 279 kJ/kg at the NaOH addition of 1.3 wt.%. 4. The specific heat of $H_2O$-NaOH at the solid and liquid state was increased in proportion to the wt.% of NaOH, when NaOH of $1.15\sim1.60$ wt.% was added to $H_2O$, the specific heat of the solid state was increased from 3.19 kJ/kg to 5.84 kJ/kg and that of liquid state from 7.8 kJ/kg to 10.28 kJ/kg. 5. When NaOH of $1.15\sim1.60$ wt.% was added to $H_2O$, the total heat storage capacity composed of sensible and latent heat was $313\sim331.3$ kJ/kg and the maximum heat storage capacity was occurred at NaOH addition of 1.30 wt. %.

• Resources Recycling
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• v.13 no.3
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• pp.37-42
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• 2004

PVC powder was dehydrochlorinated by hydrothermal reaction at reaction time 0∼5 hr, reaction temperature $200∼250^{\circ}C$ in 0∼2M NaOH solution, and shape and structure of the PVC residue was investigated. The shape of the residue was changed largely according to NaOH concentration. Most of the residue was cohered in the aqueous solution, and many pores less than 10 $\mu\textrm{m}$ were formed on the surface. Dense network structure was well developed inside the residue. On the other hand, the residue in the NaOH solution was not cohered and its shape is roughly spherical. In the IR spectrum of the residue both in water and NaOH solution at $250^{\circ}C$, aromatic rings and absorption peak by C=C double bond were observed. From the results, it was observed that aromatic circle reaction and bridge reaction occured inter and intra molecules.

• Ocean and Polar Research
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• v.38 no.3
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• pp.185-193
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• 2016

In this study, antioxidative potentials of the crude extract and its four solvent fractions from the Arctic terrestrial plant Ranunculus heperporeus were evaluated by using four different activity tests, including the inhibition of intracellular reactive oxygen species (ROS) and lipid peroxidation in Raw 264.7 cells as well as determining the extent of both the scavenging of peroxynitrite ($ONOO^-$) and the oxidative damage of genomic DNA purified from Raw 264.7 cells. Based on a comparative analysis, n-BuOH, and 85% aq.MeOH solvent fractions showed good scavenging effects on the production of intracellcular ROS and inhibited membrane lipid peroxidation and DNA oxidation. In addition, n-BuOH and 85% aq.MeOH fractions exhibited good scavenging effects on both authentic peroxynitrite and one generated from SIN-1. Among the samples tested, the n-BuOH fraction revealed the strongest antioxidant effect.