• Journal of the Korean Electrochemical Society
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• v.11 no.4
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• pp.297-303
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• 2008

$LiNiO_2$ cathode powders with fine size have been synthesized by spray pyrolysis from the spray solution with citric acid and ethylene glycol. The as-prepared powders with spherical shape, porous structure and micron size turned into $LiNiO_2$ powders with micron size and regular morphology after post-treatment at $800^{\circ}C$. The initial discharge capacities of the $LiNiO_2$ powders changed from 199 to 171mAh/g when the concentrations of the citric acid and ethylene glycol added to the spray solutions were changed from 0 to 1 M. The maximum initial discharge capacity of the $LiNiO_2$ powders obtained from the spray solution with citric acid and ethylene glycol was 198 mAh/g when the lithium component added to the spray solution was 6 mol% excess of the stoichiometric amount. The discharge capacities of the fine-sized $LiNiO_2$ powders dropped from 198 to 163 mAh/g by the 30 th cycle at a current density of 0.1 C.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.848-853
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• 2001

This research was conducted to study the effects on antigenicities (allergenicity) and structural changes of gamma-irradiated hen’s egg albumin (ovalbumin, OVA) by heating. Three groups of OVA solution (2.0 mg/mL) were prepared; 1) heat treatment; 2) irradiation after heating; 3) heating after irradiation. Samples were isothermally heated and/or irradiated at the absorption dose of 10 kGy. Competitive indirect ELISA was individually formatted with egg-allergic patients IgE (P-IgE), and mouse murine monoclonal IgG (M-IgG) and rabbit polyclonal IgG (R-IgG) for evaluating bindinhg abilities of antibodies to OVA in the sample solutions. Binding abilities of antibodies to thermally denatured OVA were changed : R-IgG to the sample treated with above 6$0^{\circ}C$, M-IgG to that above 7$0^{\circ}C$, and P-IgE to that above 8$0^{\circ}C$, respectively. P-IgE did not well recognize OVA heated at 8$0^{\circ}C$ and the above. However, binding abilities of M-IgG and R-IgG highly in creased. Significant differences of binding abilities were not observed in all samples with the combination of heat treatment and irradiation, regardless the order of the treatment. Turbidity of samples in creased both by heating and by irradiation, and the increase by irradiation was much higher than by heating. These results showed that allergenicity of OVA reduced by gamma irradiation was not affected by heating.

• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.339-344
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• 1985

Cephalosporin C(CPC) inhibited the growth of Cephalosporium acremonium M-113, a potent CPC producer derived from C acremonium ATCC 20339. Similar inhibitory effects of CPC were also observed in growth of C. acremonium ATCC 20339 and ATCC 14553. Minimum inhibitory concentrations (MIC) of CPC on the growth of conidia and hyphae of C. acremonium M-113 were 200-500 and 3000-4000$\mu\textrm{g}$/$m\ell$ respectively in synthetic medium. MIC values were increased in complex media. The inhibitory effect of CPC was due to CPC-exerted inhibition of amino acids uptake by the cells. 3'-Group of CPC might be important in its inhibitory action. In audition, CPC itself could be utilized by the cells as a nitrogen source under nitrogen limited condition.

• The Korean Journal of Pesticide Science
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• v.8 no.4
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• pp.338-346
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• 2004

The methanol extract of Chloranthus japonicus roots effectively controlled the development of rice blast(Magnaporthe grisea), rice sheath blight(Corticium sasaki), tomato pay mold(Btrytis cinerea), tomato late blight(Phytophthora infestans), and wheat leaf rust(Puccinia recondita). From the methanol extract of C. japonicus roots, three antifungal substances were isolated. Their chemical structures were determined to be shizukanols B, C, and D mainly by mass and NMR spectral data. Among the three substances, shizukanol C showed the strongest inhibitory activity against mycelial growth of the plant pathogenic fungi tested; it completely inhibited mycelial growth of M. grisea. Colletotrichum gloeosporioides, and C. acutatum at concentrations of more than $12.5{\mu}g$/ and P. infestans at concentrations of more than $3.13{\mu}g/m\ell$. They also controlled effectively the development of rice blast and wheat leaf rust. On the other hand, they caused phytotoxic symptoms on barley leaves and inhibited the growth of duckweed (Lemna paucicostata) with $EC_{50}$ values of $30.0{\mu}g/m\ell$ for shizukanol B, $49.9{\mu}g/m\ell$ for shizukanol C, and $154{\mu}g/m\ell$ for shizukanol D. In addition, shizukanol C showed an insecticidal activity against brown planthopper (Nilaparavata lugens), peen peach aphid (Myzus persicae), diamond-back moth (Plutella xylostella), and tobacco cutworm (Spodoptera litura) of the 5 arthropod pests tested with mortality values of more than 60% at a concentration of $1,000{\mu}g/m\ell$.

• Food Science and Preservation
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• v.25 no.1
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• pp.79-89
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• 2018

In this study, the anti-oxidant, whitening, and anti-wrinkle effects of Castanea crenata inner shell extracts processed by enzyme treatment and pressurized extraction were investigated. The Castanea crenata inner shell was first hydrolyzed using celluclast, viscozyme, or hemicellulase. Then, it was subjected to pressure extraction for different durations (30, 60, and 120 min). The yields of the Castanea crenata inner shell extracts processed by different enzyme treatments followed by pressurized extraction for different times are in the range of 12.42-29.80%. The total polyphenol, flavonoid, and tannin contents of the C30m (celluclast enzyme and autoclave extracts at 30 min) extract were 15.48, 10.82, and 15.82 g/100 g, respectively. The total sugar content of the H120m(hemicellulase enzyme and autoclave extracts at 120 min) extract is 61.07 g/100 g. The 1,1-diphenyl-2-pycrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities of the C30m extract at $1,000{\mu}g/mL$ are 89.20, and 81.96%, respectively. The superoxide radical scavenging and ferric-reducing antioxidant power of the C30m extract at $1,000{\mu}g/mL$ are 67.63% and $1,324.79{\mu}M$, respectively. Further, the tyrosinase and elastase inhibition activity of the C30m extract at $1,000{\mu}g/mL$ are 61.32, and 61.06%, respectively. Our results indicate that the Castanea crenata inner shell extracts processed by enzyme treatment followed by pressurized extraction could have beneficial effects on facial skin and they should be considered for use in new functional cosmetics.

• Analytical Science and Technology
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• v.16 no.6
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• pp.443-449
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• 2003

Thermal neutron irradiation experiment of boric acid solution was carried out using HANARO in following three conditions: (A) $^{10}B$ concentration = $203.0{\mu}g/mL$, irradiation time = 1 hr; (B) $^{10}B$ concentration = $381.4{\mu}g/mL$, irradiation time = 1 hr; (C) $^{10}B$ concentration = $381.4{\mu}g/mL$, irradiation time = 0.5 hr. The amount of lithium produced from $^{10}B(n{\cdot}{\alpha})^7Li$ reaction which was generated on neutron irradiation, was measured by flameless atomic absorption spectroscopy. The concentration of $^7Li$ measured in the three experiments was $0.18{\mu}g/mL$ (78.3% of theoretical value, $0.23{\mu}g/mL$) in (A), $0.31{\mu}g/mL$ (70.5% of theoretical value, $0.44{\mu}g/mL$) in (B) and $0.16{\mu}g/mL$ (71.6% of theoretical value, $0.22{\mu}g/mL$) in (C). The pH value of irradiated boric acid was shifted to considerably low. It is estimated that boric acid would be transformed into the polyborate fonn, by radiolysis products of water, which has high dissociation constant.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.243-247
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• 2007

A selective analytical method of headspace-GC/MS has been applied to determine levels of benzene in beverages. Food samples were 85 including 2 fruit juices, 6 fruit beverages, 11 carbonated beverages, 55 mixed beverages, and 4 beverage concentrations, and 7 extracted beverages. For phase equilibration of headspace, sample was stirred at $40^{\circ}C$ for 30 min. The oven temperature was $60^{\circ}C$ and elevated to $180^{\circ}C$ at $15^{\circ}C/min$. The internal standard was benzene-d6. The identification was done by the selected target ions such as m/z 51, 77, and 78 and the confirmation was done by the response ratio of m/z 77 to m/z 78 between sample and standard. The overall recoveries were ranged from 91% to 101% and the limit of quantification was $1{\mu}g/kg$. The average level of benzene were $5{\mu}g/kg$ for fruit beverages, $2{\mu}g/kg$ for carbonated beverages, $7{\mu}g/kg$ for mixed beverages and $7{\mu}g/kg$ for extracted beverages.

• Journal of the Korean Solar Energy Society
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• v.29 no.3
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• pp.45-50
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• 2009

To estimate the operating performances of the geothermal heat exchange pipe(GHEX), GHEXs of 400RT geothermal system were measured and analyzed through a year. The followings are the results. The temperature of 2 GHEXs installed 4m apart was fluctuated very similarly. When the geothermal system is nor operating or is operating as heating mode, the temperature of G.L.-170m was always higher than G.L.-70m's. But it reversed when the geothermal system is operating as cooling mode. And through a year, it has been observed that the temperature of G.L.-170m is increased approximately $1.5^{\circ}C$. With previously mentioned results, the heat transfer capacity of G.L.-70m's geological stratum is estimated as higher than that of the G.L.-170m.

• Bulletin of the Korean Mathematical Society
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• v.36 no.2
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• pp.337-342
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• 1999

M. Cohen and S. Montgomery showed that a Maschke-type theorem for the smash product, which unlike the corresponding result for group actions, does not require any assumptions about the characterstic of the algebra. Our purpose in this paper is a Maschke-type theorem for the graded smash coproduct C⋊kG: let V be a right C⋊kG-comodule and W a C⋊kG-subcomoduleof V which is a C-direct summand of V. Then W is a C⋊kG-direct summand of V. Also this result is equivalent to the following : let V be a graded right C-comodule and W a graded subcomodule of V which has a complement as a C-subcomodule of V. Then W has a graded complement.

• Korean Journal of Mathematics
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• v.29 no.3
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• pp.577-580
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• 2021

For a finite simplicial graph 𝚪, let G(𝚪) denote the right-angled Artin group on the complement graph of 𝚪. For path graphs P_k, cycle graphs C_ℓ and complete bipartite graphs K_n,m, this article characterizes the embeddability of G(K_n,m) in G(P_k) and in G(C_ℓ).