• Journal of Mushroom
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• v.2 no.4
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• pp.192-199
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• 2004

The mycelial mass of K. mutabilis greatly increased at pH 5.5~6.0 but decreased pH 6.0. The linear mycelial growth wsa mostly supported on sawdust of Quercus accutisima and the mycelial density wsa high on sawdust of Q. accutisima and corn cob. Much mycelial distribution could be showen in ray parenchyma cell and ray tracheid. Severe degradation of ray parenchyma cell was found but little degradation of ray tracheid cell was found. The dry weight loss wsa 5.9% after agar-block test. And the pH wsa acidified from 6.07 to 4.31 and hot water extractives was decreased after degradation of Q. serrata sawdust by K. mutabilis.

• Journal of fish pathology
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• v.20 no.2
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• pp.139-145
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• 2007

To decrease stress in eel (Anguilla japonica) during its culture or transportation, aspirin (ASA) known as analgesic, antiinflammatory and antithrombic agent was administrated by dipping or oral routes. Concentrations of aspirin (ASA) and salicylic acid (SA) in eel plasma were simultaneously measured by a high performance liquid chromatography (HPLC). The plasma was acidified with 0.2 M HCl and 0.2 M orthophosphoric acid, and mixed with acetonitrile. ASA and SA extracted with acetonitrile were analyzed by the HPLC equipped with reversed phase Novapak C18 column (4 ㎛ silica, 150×4 mm) and UV detector(237 nm). The mobile phase consisted of 740 ㎖ water, 900 ㎕ orthophosphoric acid (85%) and 180 ㎖ acetonitrile. The retention times of ASA, SA and 2-methylbenzoic acid(MBA) were 4.8 min, 8.4 min and 11.5 min, respectively. The limit of quantification was 0.01 ㎍/㎖ for SA and 0.05 ㎍/㎖ for ASA. The mean recovery from eel plasma was 70.8～99.6% for ASA and 95.2～100.3% for SA. This HPLC method was applied to analyze ASA and SA of eel plasma after either dipping in a concentration of 20 ppm or feeding the feed supplemented with 50 ㎎/kg BW. Only SA was detected in eel plasma after the administration of ASA by dipping or oral routes because the drug was quickly decomposed into SA in eel plasma. The amount of SA in eel plasma reached the highest value at 3hr in dipping and 7 days in oral administration. When the ASA-administrated eel were kept in ASA free aquaria, 0.02-0.03 ㎍/㎖ of SA were detected 48 hr after the administration in both routes.

• Journal of the Korean Institute of Gas
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• v.7 no.2 s.19
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• pp.22-32
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• 2003

Al-brass material is generally used at the state of plastic deformation, for example; bending, extension of bell mouth at shell and tube type heat exchanger. And SCC(stress corrosion cracking) of Al-brass material will be affected by residual stress as plastic deformation. SCC results from synergism between mechanical factor and corrosion environment. Mechanical factor is stress that directly relates with stress intensity factor at the crack tip. This paper was studied on the effect of stress on SCC of Al-brass tube under in $3.5\%$ NaCl. + $0.1\%\;NH_4OH$ solution by constant displacement tester. Increasing of acidified water flow into sea and speeds up corrosion rate of Al-brass which is used as a tube material of vessel heat exchanger by polluted coast seawater. The experimental results are as follow The latent time of SCC occurrence gets longer as the initial stress intensity factor($K_{Ii}$) gets lower The main crack was propagated as the initial stress intensity factor($K_{Ii}$) gets higher, and secondary cracks occurred by electro-chemical factor a(ter stage of released stress. Dezincification phase showed around the crack, and the range of dezincification gets wider as the initial stress intensity factor($K_{Ii}$) gets higher.

• Journal of Life Science
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• v.18 no.8
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• pp.1123-1131
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• 2008

This study was performed to confirm of biological function of black garlic, it heated for 11 days at $40{\sim}90^{\circ}C$ (first step: heate for 2 days at $90^{\circ}C$, second step: heated for 4 days at $80^{\circ}C$, third step: heated for 4 days at $60^{\circ}C$ and fourth step: heated for 1 day at $40^{\circ}C$). Samples were analyzed physico-chemical characteristics and antioxidant activity. Hunter L, a and b values were decreased during processing, and then inner part Hunter values were highly decreased at the second step. The moisture contents were decreased to 58.48${\pm}$0.41 g/100 g at fourth step. pH was also acidified to pH 4.22${\pm}$0.02, but O.D. value at 420 nm was increased during processing of black garlic. At fourth step, total phenolics and flavonoids contents were increased about 1.9 and 2.6 folds than first step sample. Also, total pyruvate and thiosulfinate contents were increased about 1.6 and 5.8 folds as change of total phenolic and flavonoid contents, respectively. Fructose contents were the highest level among free sugars and its contents increased to 2,454.45${\pm}$4.20 mg/100 g. Contents of sucrose and maltose were decreased during processing of black garlic. The contents of total minerals were the highest at fourth step (1,009.20${\pm}$6.91 mg/100 g) during its processing. Contents of glutamic acid, proline and aspartic acid were detected higher than other composition amino acids. Taurine and ethanolamine were not detected in the first step sample, but they were detected 0.88${\pm}0.60{\sim}1.06{\pm}$0.04 and 0.28${\pm}0.4{\sim}0.5{\pm}$0.09 mg/100 g in next processing step, respectively. DPPH radical scavenging ability of water and ethanol extracts from black garlic was increased during its processing. Abilities of DPPH radical scavenging were the highest in fourth step sample, its abilities were 67.40${\pm}$0.21% in 1,000 ${\mu}g/ml$ of water extracts. Reducing power was also significantly higher in water extract than ethanol extract on the whole.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1174-1181
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• 2008

Garlics were aged at 60, 70, 80, and $90^{\circ}C$ for 1, 3 and 6 days. Samples were analyzed for physico-chemical components and antioxidant activities, such as DPPH scavenging activity and reducing power of hot water and ethanol extracts. The Hunter L, a and b values were significantly lower in sample aged at higher temperature and for longer time. In initiation of aging, the share force was the lowest in sample aged at $90^{\circ}C(85.70{\pm}1.44\;kg/cm^2)$ and it increased for 6 days to $411.30{\pm}13.90\;kg/cm^2$ in aging. The pH of garlic was acidified at increasing aged temperature and periods. In sample aged for 6 days at $60^{\circ}C$ and $90^{\circ}C$, pH was 6.12 and 3.90, respectively. Contents of total phenolics and flavonoids also increased in sample aged at higher temperature and for longer time. Their contents increased about 3.5 and 9.1 times higher in sample aged for 6 days at $90^{\circ}C$ than sample aged for 6 days at $60^{\circ}C$, respectively. Total pyruvate contents were fluctuated by aging temperature and periods. DPPH scavenging activity was increased in sample aged at higher temperature and longer time. The highest activity of DPPH scavenging showed $87.48{\pm}0.20%$ in sample aged for 6 days at $90^{\circ}C$. Similar results were observed in reducing power activity. It was estimated that such increases in anti-oxidant activities in aged garlics may come from actions of phenolics, flavonoids and browning compounds in them.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.257-271
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• 2002

One of the main interests in relation to heavily contaminated gully-pot sediment in urban area is the short term mobility of heavy metals, which depends on the pH of acidic rainwater and on the buffering effects of carbonate minerals. The buffering effects of carbonates are determined by titration (acid addition). Leaching experiments are carried out in solutions with variable initial HN03 contents for 24h. The gully-pot sediment appears to be predominantly buffered by calcite and dolomite. In case of sediment samples, which highly contain carbonates, pH decreases more slowly with increasing acidity. On the other hand, for the sediment samples, which less contain carbonate minerals, pH rapidly drops until it reaches about 2 then it decreases slowly. The leaching reactions are delayed until more acid is added to compensate for the buffering effects of carbonates. The Zn, Cu, Pb and Mn concentrations of leachate rapidly increase with decreased pH, while Cd, Co, Ni, Cr and Fe dissolutions are very slow and limited. The solubility of heavy metals depends not only on thc pH values of leachatc but also on the speciation in which metals are associated with sediment particles. In slightly to moderately acid conditions, Zn, Cd, Co, Ni and Cu dissolutions become increasingly important. As deduced from leaching runs, the relative mobility of heavy metals at pH of 5 is found to be: Zn > Cd > Co > Ni > Cu » Pb > Cr, suggesting that moderately acid rainwater leach Zn, Cd, Co, Ni and Cu from thc contaminated gully-pot sediment, while Pb and Cr would remain fixed. The buffering effects of Ca- and Mg-carbonates play an important role in delaying as well as limiting the leaching reactions of heavy metals from highly contaminated gully-pot sediment. The extent of such a secondary environmental pollution will thus depends on how well the metals in sediment can be leached by somewhat acidic rain water. Changes in the physicochemical environments may result in the severe environmental pollution of heavy metals. These results are to be taken into account in the management of contaminated sediments during rainstorms.