• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.700-704
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• 2008

Nitrite and free ammonia have been known as substrate inhibitors in anaerobic ammonium oxidation. To reduce inhibitory effect of these substrates, the NH$_3$-N/NO$_2$-N ratio in the influent could be properly controlled in anaerobic ammonium oxidation process. Five kinds of NH$_3$-N/NO$_2$-N ratio were assayed in batch to find optimum NH$_3$-N/NO$_2$-N ratio, curtailing substrate inhibition. As the results of batch test, the highest T-N removal efficiency of 88% was obtained at 1.00 : 1.30 of NH$_3$-N/NO$_2$-N ratio. In addition, rate constants for ammonium and nitrite in zero-order kinetics were found to be the highest values as 7.66 mg/L$\cdot$hr and 11.89 mg/L$\cdot$hr at 1.00 : 1.30 ratio, respectively. However, as for the specific anammox activity, the ratio of NH$_3$-N/NO$_2$-N ratio was recommended as 1 : 1.15 which can maintain the highest SAA during continuous operation and preclude the accumulation of nitrite in the reactor.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.333-336
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• 2008

The groove rolling is a process that transforms the bloom or billet into a shape with circular section through a series of rolling. Inhibition of surface defect generation in groove rolling is a matter of great importance and therefore many research groups proposed a lot of models to find the location of surface defect initiation. In this study, we propose a model for maximum shear stress ratio over equivalent strain to catch the location of surface defect onset. This model is coupled with element removing method and applied to box groove rolling of POSCO No. 3 Rod Mill. Results show that proposed model in this study can find the location of surface defect initiation during groove rolling when finite element analysis results is compared with experiments. The proposed criterion has been applied successfully to design roll grooves which inhibits the generation of surface defect.

• Journal of the Korean Society of Food Culture
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• v.31 no.2
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• pp.178-187
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• 2016

The principal objective of this study was to investigate the quality characteristics of Yukwa prepared with chlorella powder. The tested concentrations of chlorella powder were 0, 1, 2, and 3%. As more chlorella powder was added, spread ratio, moisture content, and volume increased, whereas L-value and a-value decreased and b-value increased. The hardness of Yukwa made with 3% chlorella powder was highest among the samples. The results of the sensory evaluation test show that Yukwa with 1% chlorella powder was significantly more preferable in term sof overall acceptability. The acid value and peroxide values were lower in Yukwa prepared with chlorella powder than the control. Yukwa prepared with chlorella powder showed strong inhibition of lipid oxidation. Thiobarbituric values were lower in Yukwa prepared with 2% chlorella powder compared to Yukwa prepared with 1% and 3% chlorella powders and control Yukwa. These results suggest that chlorella powder can be applied to Yukwa for high quality and functionality.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.425-431
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• 1995

A kinetic model of the cyclodextrin formation in a heterogeneous enzyme reaction system using swollen extrusion starch as substrate was derived emphasing the structural features of extrusion starch. The degree of gelatinization, the ratio of accessible and inaccessible portion of extrusion starch, adsorption of CGTase on swollen starch, the structural transformation during reaction, and product inhibition caused by produced CDs were considered in deriving kinetic model. Various kinetic constants were also evaluated. The derived kinetic equation was numerically simulated, which result showed that the derived kinetic equations can be used to predict the experimental data reasonably well under the various experimental conditions. Kinetic model can be utilized for the optimization of enzyme reactor and the process development for CD production from swollen extrusion starch.

• Journal of Environmental Science International
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• v.23 no.5
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• pp.861-871
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• 2014

This study analyzes the characteristics of ozone weekend effect(OWE) in Busan. $O_3$ concentration on Sunday was over 10% higher than that on weekdays in all areas except for Kwangbokdong, Taejongdae, and Joadong. Such a difference was higher in the industrial area than in the residential area. $O_3$ generation was facilitated by the decrease in $NO_X$ emission on Sunday in VOC-limited regime where the VOC/$NO_X$ ratio is low. Low NO concentration in the Sunday morning decreased inhibition of $O_3$. NO-$O_3$ crossover time on Sunday was shorter than that on weekdays which in turn extended the accumulated duration of $O_3$. Future studies can include whether the entire Busan is VOCS-limited or the coastal area is VOCS-limited while the inland area is $NO_X$-limited.

• Herbal Formula Science
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• v.11 no.2
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• pp.197-212
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• 2003

Antigenotoxicity test (SOS chromotest) and antimutagenecity test (Ames test) were carried out using water-soluble and methanolic extracts from Dianthi Herba. Antigenotoxic activity of methanolic extract against mutagens both MNNG and NQO was much more effective than that of water-soluble one. When the extract was added to the certain concentration $(100\;{\mu}l/tube)$, antigenotoxic activities against both mutagens were enhanced. Against the mutagen MNNG with Ames test, antimutagenic activity of the methanolic extract was better than that of water-soluble one. The 74.6% of inhibition ratio for revertant forming CFU/plate was shown at $300\;{\mu}l/plate$ of the methanolic extract.

• Proceedings of the Korean Society of Crop Science Conference
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• 2002.05a
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• pp.77-81
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• 2002

The scope of the research is investigation of immune-modulating activities of A. rugosa (Baechohyang) extract was preformed through the screening active constituents using in vitro assays and evaluating anti-inflammatory activity and anti-atherosclerotic activity of the extract and active compound (tilianin) in vivo. In addition, various functional foods using the extract and whole plant was developed. The extract showed strong anti-inflammatory activity in carrageenan-induced acute edema mouse model and anti-atherogenic lesion activity in LDLR (low density lipoprotein receptor) deficient mouse model. These activities were thought to be resulted from modulation activity of several pathways of inflammation process. Among the main constituents of Baechohyang, polyunsaturated fatty acids (PUFA), Phytosterols, oleanolic acid and rosmarinic acid showed anticomplement activity, and PUFA, acacetin and tilianin newly showed potent ICAM-1 expression inhibition activity. The processes of extraction, mixing ratio of additives and storage conditions were established for drinks, granule tea, leaf tea, mixed tea and furigake.

• Microbiology and Biotechnology Letters
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• v.23 no.2
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• pp.220-228
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• 1995

For polyhydroxyalkanoic acid (PHA) production, several microorganisms were isolated from sewage sludge. One of them, GB-77 strain, was chosen from its PHB/HV copolymer production on only fructose without cosubstrate. The isolated strain GB-77 was identified as the genus Alcaligenes. Optimal temperature and pH for cell growth were 36C and 6.8. Optimal medium composition was 10 g/l of fructose and 5 g/l of polypeptone, 1 $\times$ 10$^{-2}$M Na$^{2}$HP0$^{4}$, 1.3 $\times$ 10$^{-2}$M KH$^{2}$PO$^{4}$. To investigate the optimal condition for polyhydroxyalkanoic acid production two-stage culture technique was used; first stage for cell growth and second stage for PHA production on unbalanced growth conditions. Optimal conditions for high PHA production were C/N ratio 50, temperature 36$\circ$C and pH 6.8. To overcome fructose inhibition on cell growth, intermittent feeding fed-batch culture technique was used. Total cell concentration was 17.4 g/l with 9.1 g/l of PHA. The purified PHA was identified PHB/HV copolymer by NMR analysis.

• Journal of Nutrition and Health
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• v.29 no.8
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• pp.867-873
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• 1996

This study was undertaken to determine whether the anabolic steroid nandrolone phenylpropionate(NPP) can inhibit the muscle atrophy and reduction in muscle protein synthesis caused by glucocorticoids in female rates. Daily injections of 50mg/kg of corticosterone for eight days induced significant reductions in body weight gain and protein without affecting food intake. The mass, protein and RNA content, ratio of RNA to protein, and fractional rate of protein synthesis, measured in vivo, of gastrocnemius muscle were all significantly reduced by corticosterone treatement. Simultaneous administration of NPP at a dose of 10mg/kg with corticosteorne (50mg/kg) fully inhibited the reductions in the mass, protein and RNA content of gastrocnemius muscle, and body weight gain and protein with no alteration in food intake but the reduction in fractional rate of muscle protein syntheis was only partially prevented. The results indicate that the anabolic steroid nandrolone phenylpropionate is capable of preventing muscle atrophy in female rats treated with excess corticosterion.

• Journal of Nutrition and Health
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• v.26 no.4
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• pp.379-389
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• 1993

Several studies have shown that extracts from yellow-green vegetables reveal antitumor activities. In the present study we investigated the effect of phytol in order to elucidate the immunological mechanism of antitumor activity of this substance. The results obtained from the experiment as follows: 1) Phytol showed cytotoxic effect on sarcoma 180 cells in vitro. 2) When phytol was injected into the peritoneal cavity of mice transplanted with sarcoma 180 cells, the average survival time (24.0 days) tended to increase as compared with the nontreated control (19.2 days). 3) When sarcoma 180 cells were injected subcutaneously into the right groin of mice, and then phytol was injected into the peritoneal cavity, the tumor inhibition ratio was 33%. 4) The natural killer(NK) cell activity was significantly augmented by phytol in vitro and in vivo. Similar augmentations of NK cell activity were obtained with culture supernatants of phytol exposed spleen cells and peripheral blood mononuiclear cells. 5) Phytol on the macrophage from peritoneal cavity showed a higher effectiveness in vivo than in vitro. These results indicate that phytol shows the inhibitory effect for growth of sarcoma 180 cells in vitro, also it can augment macrophage and NK cell activities in vivo.