• KSBB Journal
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• v.17 no.6
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• pp.566-570
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• 2002

In lactic acid fermentation, the end product inhibition by lactic acid causes several problems. The most important of which are low lactate formation rate and its recovery from fermentation broth. To overcome these problems, extractive lactic acid fermentation was carried out in a bioreactor, which was connected to a column packed with anion exchange resin (Amberlite IRA-400, 250 g). The system was started as a batch process, and then the separation process was started when the lactic acid concentration reached 10 g/L, 20 g/L or 30 g/L. In each case, total lactic acid concentration was reached to 48.6, 53.6, 52.6 g/L with its productivity of 1.2 g/L $.$ h, 1.6 g/L $.$ h, and 1.3 g/L $.$ h, respectively Especially, in the case of the 20 g/L recycling-initiation process, extractive fermentation reduced tie fermentation time (17 hrs) by 34% in comparison with the conventional batch process. The direct consequence of this time reduction was shown by a 1.8 fold increase in overall lactic acid productivity.

• The Korean Journal of Food & Health Convergence
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• v.6 no.1
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• pp.9-15
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• 2020

Salinity with sodic condition disturbs germination, retards emergence, and slow down seedling development of Lemon Grass (Cymbopogon citratus).Lemongrass is a perennial grass plant widely distributed worldwide and most especially in tropical and subtropical countries. This research experiment was designed to evaluate the influences of (4 dSm^-1+ 13.5 (mmol L^-1)^-1/2, 5 dSm^-1+ 25 (mmol L^-1)^1/2, 5 dSm^-1+ 30 (mmol L^-1)^1/2, 10 dSm^-1+ 25 (mmol L^-1)^1/2 and 10 dSm^-1+ 30 (mmol L^-1)^1/2) on biomass produce of lemon grass against salt tolerance. The uppermost biomass yield (45.53 gpot^-1) was produced by 4 dSm^-1+ 13.5 (mmol L^-1)^1/2 treatment. The increase in the intensity of salts reduced the growth of lemon grass. Lower biomass yield (79.33 gpot^-1) was gained at 10 dSm^-1+ 30 (mmol L^-1)^1/2. 5 dSm^-1+ 25 (mmol L^-1)^1/2 treatment performed enhanced outcome i.e. the least reduction % over control (5.87). Salinity- sodicity showed serious effect on the growth reduction from 5.87% to33.60%. This reduction gap was affected by the negative effect of salinity and sodicity on Linseed growth. Salinity- sodicity showed severe impact on the growth reduction from 5.87% to33.60%. Based on the findings, lemon Grass (Cymbopogon citratus).was capable to grow up the maximum at 4 dSm^-1+ 13.5 (mmol L^-1)^1/2 treatment.

• Korean Journal of Materials Research
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• v.9 no.8
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• pp.849-853
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• 1999

In the study, superconducting properties of $Bi_2$-x(sub)$LSr_2$Ca(sub)1+x(sub)$LCu_2$O(sub)8+d (x(sub)L=0, 0.05, 0.1, 0.2) films prepared by the LPE method was investigated. The peak decompositions of Sr3d and Ca2p XPS spectra, together with the EPMA results, elucidated the occupancies of Bi, Sr and Ca atoms on the SrO- and Ca-layers. The lattice parameter c monotonically increased with increasing x(sub)L for $0\leq$x(sub)L$\leq$0.2. The superconducting critical temperature T(sub)c showed a maximum value around x(sub)L=0.1. The x(sub)L dependence of the superconducting critical temperature T(sub)c and the lattice parameter c are explained by the changes of the excess oxygens in the BiO-layer. Since distribution and deficiency of the atoms in SrO-layer have influenced on superconducting properties and crystal structure.

• Korean Journal of Plant Resources
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• v.21 no.5
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• pp.357-361
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• 2008

The photosynthetic characteristics of three Ligularia species, L. fischeri, L. fischeri var. spiciformis and L. stenocephala under-tree cultivated in Dunnae-myeon, Hoengsung-gun were measured and compared. Total mean photosynthetic rate increased with increasing the light intensity up to 2,000 PPFD. Mean photosynthetic rate of L. fischeri increased to maximum value of $21.1{\mu}mol\;CO_{2}m^{-2}s^{-1}$ with increasing the light intensity up to 1,600 PPFD, but it was decreased at 2,000 PPFD. The highest photosynthetic rate was shown in L. fischeri var. spiciformis, followed by L. fischeri, and L. stenocephala. was the highest $27.39{\mu}mol\;CO_{2}m^{-2}s^{-1}$ among three species, followed by that of The differences in photosynthetic rates were significantly different among the species each measuring date. L. fischeri var. spiciformis was more adaptive species at the low elevated under-tree cultivated sites, such as, Sanchemaeul Dunnae-myeon Hoeyngseung-gun than L. fischeri and L. stenocephala.

• The Korean Journal of Food And Nutrition
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• v.5 no.1
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• pp.7-12
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• 1992

This study was devised to observe the inhibitory effect of 7 kinds PG(PG1, PG2, PG3, PG4, PG5, PG6 and PG7) and of 5 kinds PG4(PG41, PG42, PG43, PG44 and PG45) of the acidic polysaccharide fraction from Korean red ginseng on a lipolytic action of Toxohormone-L. Toxohormone-L is a lipolytic factor, found in ascites fluid. of sarcoma-180 bearing mice and of patients with hepatoma. A substance that inhibited the lipolytic action of toxohormone-L was isolated from red ginseng powder. This substance was an acidic polysaccharides In vitro test showed that the inhibitory effect of PG4 and PG43 fraction of the lipolysis by Toxohormone-L was highest percent among other treatments at concentration of 50, 100, 200, 500 and 1,000ug/ml of reaction mixture. And total inhibitory activity(units) of PG1 and PG4, and PG4 s was highest among other treatments at the same concentration.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.1
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• pp.107-112
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• 2011

In this study, photocatalytic degradation and mineralization of bisphenol A (BPA), which has been listed as one of endocrine disruptors, were carried out in the CPC system using $Tio_2$ slurry and UVA irradiation. The degradation efficiency has been investigated under the controlled parameters including initial concentration (5, 10, 20 mg/L), dosage of $Tio_2$ (0.1, 0.5, 1.0 g/L), UVA power (0, 80, 120 W) and temperature (0, 20, 30). At 10mg/L of initial concentration, BPA was degraded above 80% after 10min, BPA were degraded 97% and 49% at 20 mg/L and 30 mg/L, respectively. At $Tio_2$ dosage was 0.1 and 0.5 g/L, the degradations of BPA showed similar trend and were about 70% after 1 hr, and the degradation of BPA was above 80% after 30 min at 1 g/L of $Tio_2$ dosage. The increase of degradation seem to be due to the increase in the total surface area, namely number of active sites, available for the photocatalytic reaction as the dosage of photocatalyst increased. When the UVA power was 120 W, BPA was degraded rapidly above 60% after 10min of reaction time. To investigate the effect of temperature, carried out experiment controlled temperature, there were no significant differences depending on the temperature. After 1hr, the degradation of BPA were 46%, 67%, and 69% at 10, 20 and $30^{\circ}C$.

• Journal of Photoscience
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• v.11 no.3
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• pp.107-113
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• 2004

Synthesis, absorption and fluorescence properties of 3-methyl indole (1), N-(benzenesulfonyl)-3-(3-oxo-but-1-enyl)-indole (2) and 1H-3-(3-oxo-but-1-enyl)-indole (3) are described. Extended conjugation at C-3 of indole as in 3 causes moderate resolution of $^1L_a$ and $^1L_b$ bands. However, 2 having an electron-withdrawing group at indolic nitrogen shows only the $^1L_a$ band. While the $^1L_b$ band largely remains solvent polarity independent, the $^1L_a$ band undergoes moderate red shift in polar solvents. The fluorescence in 2 and 3 originates from the $L_b$ transition. Additionally, interaction of 2 and 3 with BSA indicates that these compounds bind to the hydrophobic site of BSA with the formation of a highly fluorescent BSA-probe complex.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.23 no.4
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• pp.184-188
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• 1987

The author studied to analyse the relationship between the body dimension of sea eel, Astroconger myriaster and the mesh size of fishing gears. The samples were caught by traps and pots during September, 1987 in the Southern Sea of Korea. The results obtained can be summarized as follows: 1. The relationship between total length L, body weight W and diameter D may be expressed as: W=3.58$\times$10 super(-4) L super(3.38) (r=0.99). D=0.07 L-0.59 (r=0.99). W=10.38 D super(2.76) (r=1.00). W=1/2$\times$D super(2).L. 2. The mesh size of traps and the hole diameter of post must be more than 29.2 mm and 18.6 mm, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.529-534
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• 1994

The lethal concentration(LC50) of several micropollutants for three species of the fish Paralichthys olivaceus, Mugil cephalus and Sebastes schlegeli were determined by acute toxicity tests. For the determination of definitive test concentrations, the fish were exposed to three test material concentrations spaced at order-of-magnitude intervals based on a logarithmic ratio in range finding tests. LC50 was determined by five concentrations of test material in a geometric progression by means of range finding tests. The 96hr-LC50 values(mg/l) were estimated by the graphical interpolation of probability-logarithm transformations. These indicated that the order of sensitivities to three kind of micropollutants was Mugil cephalus > Paralichthys olivaceus > Sebastes schlegeli.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.194.1-194.1
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• 2007