• KSBB Journal
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• v.31 no.4
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• pp.312-314
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• 2016

This study was carried out to determine the antifungal activity of $SeO_2$ against pathogenic fungus, Candida albicans. Concentration-dependent Inhibitory activity of $SeO_2$ against C. albicans was shown. When $400{\mu}g/disc$ of $SeO_2$ was tested, the inhibition size ranged from 20.7 to 26.8 mm (avg. 23.4 mm). MIC values of $SeO_2$ against cell growth of C. albicans ranged from 50 to $100{\mu}g/mL$ (avg. $70{\mu}g/mL$). These results could be applied to antibiotics-resistant C. albicans and other pathogenic fungi.

• Journal of the Korean Chemical Society
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• v.42 no.6
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• pp.629-637
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• 1998

The HF-SCF, MP2 and B3LYP calculations have been performed on the two conceivable clusters $(HF)_2(CO)$ trimers as well as their dimer complexes FH…FH, FH…CO and FH…OC applying $6-31+G^{\ast}^{\ast}$, and $6-311+G^{\ast}^{\ast}$ basis sets. A variety of ground state properties of these trimer complexes have been listed, and compared with corresponding properties of isolated monomers and combined dimers. It was calculated that FH…CO is more stable than FH…OC by average 0.85 kcal/mol and F-H…F-H…C≡O is more stable than F-H…F-H…O≡C by 1-2 kcal/mol. The C≡O stretching bands of the F-H…F-H…C≡O and F-H…F-H…O≡C were red shifted by 24, $37\;cm^{-1}$ compared with the FH…CO and FH…OC respectively. Also, H-F stretching bands were red shifted by 54 and $353\;cm^{-1}$.

• Journal of the Korean Ceramic Society
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• v.39 no.6
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• pp.598-603
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• 2002

The effects of alumine borosilicate glass composition on the densification and the microwave properties of (M $g_{0.93}$C $a_{0.07}$)Ti $O_3$ ceramics were studied. As the amount of glass increase, the density of ceramics increases and grain growth enhances. When 20 ~30 wt% of glass added, it was densified to over 95% of (M $g_{0.93}$C $a_{0.07}$)Ti $O_3$ theoretical density. (M $g_{0.93}$C $a_{0.07}$)Ti $O_3$ ceramic sintered at 95$0^{\circ}C$ exhibits dielectric constants of 15~16, quality factor of 8000 and temperature coefficient of resonant frequency of -45 ppm/$^{\circ}C$ by adding 20 wt% alumine borosilicate glass.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.402-407
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• 2012

The effects of a combined treatment of aqueous chlorine dioxide ($ClO_2$) and ultraviolet-C (UV-C) irradiation on microbial growth in celery and cherries were investigated. Celery and cherry samples were treated with 50 ppm $ClO_2$, UV-C at dose of 10 kJ/$m^2$, and a combination of $ClO_2$ and UV-C. The changes in the counts of Escherichia coli O157:H7 inoculated in the celery and cherries as well as those of total aerobic bacteria, yeast and molds in the celery and cherries were investigated after each treatment. After the combined treatment of aqueous $ClO_2$ and UV-C irradiation, the populations of E. coli O157:H7 in the inoculated celery and cherries were reduced by 2.8 and 3.0 log CFU/g, respectively, compared to those of the control. For the un-inoculated celery and cherries, the populations of total aerobic bacteria were reduced by 2.9 and 1.8 log CFU/g, respectively, compared to the control. In addition, the populations of yeast and molds were decreased by 1.8 and 1.2 log CFU/g, respectively. These results suggest that the combined treatment of 50 ppm $ClO_2$ and UV-C at a dose of 10 kJ/$m^2$ would be an effective technology for decontamination and improving the microbiological safety in celery and cherries during chilled storage.

• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.861-867
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• 2019

$Li_4Ti_5O_{12}$ is a promising next-generation anode material for lithium-ion batteries due to excellent cycle life, low irreversible capacity, and little volume expansion during charge-discharge process. However, it has poor charge capacity at high current density due to its low electrical conductivity. To improve this weakness, porous $Li_4Ti_5O_{12}$ was synthesized by sol-gel method with P123 as chelating agent. The physical characteristics of as-prepared sample was investigated by XRD, SEM, and BET analysis, and electrochemical properties were characterized by cycle performance test, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS). $Li_4Ti_5O_{12}$ synthesized by 0.01mol ratio of P123/Ti showed most unified particle size, high specific surface area, and relatively high porosity. EIS analysis showed that depressed semicircle size was remarkably reduced, which suggested resistance value in electrode was decreased. Capacity in rate performance showed 178 mAh/g at 0.2C, 170 mAh/g at 0.5C, 110 mA/h at 5C, and 90 mAh/g at 10C. Capacity retention also showed 99% after rate performance.

• Journal of the Korean Ceramic Society
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• v.39 no.11
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• pp.1108-1112
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• 2002

pellets were fabricated as a reactor control material by the powder process. Sinterability of $Dy_2O_3+TiO_2$ mixtures and phases of solid solutions were analyzed by using TMA and XRD, respectively. The thermal conductivity of pellet was determined from the measurement data of the specific heat and the thermal diffusivity of the pellet. The sinterability and the sintered density varied as a function of Dy content in $Dy_xTi_yO_z$. The pellet of $3\;g\;Dy/cm^3\;Dy_xTi_yO_z$ melted in the sintering temperature of $1580{\circ}C$. There were two phases of $Dy_2TiO_5+Dy_2Ti_2O_7$ and a single phase of $Dy_2TiO_5$ for the pellet that has the Dy content of and , respectively. The thermal conductivity of $Dy_xTi_yO_z$ was nearly constant in the temperature range of $25~600{\circ}$. It was 1.69~1.78 W/mK for the pellet sintered in and 1.49~1.55 W/mK for the pellet sintered in $1550{\circ}$.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.185-192
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• 2000

This study was conducted to develop mathematical model of respiration rate of cucumber plant under varying environmental conditions. 8.55% of gross photosynthesis of individual cucumber plant was used as respiration. Growth respiration coefficient was estimated as 0.0935. Maintenance respiration rate was estimated as 0.00158g CH$_2$g$^{-1}$ .h$^{-1}$ at 24$^{\circ}C$ of air temperature and it increased exponentially as air temperature became higher. Respiration rate decreased poportionally as content of storage carbohydrate became lower. Ion uptake respiration rate of roots was estimated as 0.6648g C$H_2O$.(gN)$^{-1}$ .

• Korean journal of applied entomology
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• v.35 no.4
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• pp.297-301
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• 1996

This test has been carried out to evaluate the effect of temperature on the growth of the insecticide susceptible strain, URY-O nomal genotype and insecticide resistant strain, O-RT abnormal genotype, and ABURABI nomal genotype. The nymphal periods were not significantly different between URY-O and O-RY strains at $25^{\circ}C$. At $30^{\circ}C$, susceptible strain URY-O could give birth to offsprings almost nomally, while resistant strain O-RY could not produce any offspring for 20 days which results in nymphal death. The numbers of offsprings of strain URY-O and strain ABURABI were not different between $25^{\circ}C\;and\;28^{\circ}C$, but strain O-RY, when it was reared at $28^{\circ}C$, could produce offsprings only 10% of those at $25^{\circ}C$. Body weight of strain URY-O and strain ABURABI were 0.22mg/female and 0.27mg/female, respectively at $28^{\circ}C$, however that of O-RY was only 0.16mg/female, showing considerable difference between normal and abnormal genotype. Substrain O-RY(+) which has high esterase activity showed poor reproduction ability(0.8 progenies per $G_{1}$ individual than substrain O-RY(-) (3.4 progenies per $G_{1}$ individual) which has low esterase activity at $28^{\circ}C$

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1408-1413
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• 2017

The aim of this study was to investigate the antioxidant activities and protective effects of hot water extract from Curcuma longa L. (CLW) on oxidative stress-induced C2C12 myoblasts. Antioxidant activities of CLW were evaluated based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities. Protective effects of CLW on oxidative stress-induced C2C12 myoblasts were determined based on cytotoxicity, $H_2O_2$ protective activity, and intracellular reactive oxygen species (ROS) level. DPPH and ABTS radical scavenging activities represented by $SC_{50}$ were $188.5{\pm}3.0{\mu}g/mL$ and $92.0{\pm}0.9{\mu}g/mL$, respectively. Using C2C12 myoblasts, CLW treatment increased cell viability against oxidative stress-induced cell death. Further, CLW treatment reduced the intracellular ROS level in cells treated with $H_2O_2$. These results suggest that CLW might have the capability to protect oxidative stress-induced C2C12 myoblasts.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.140-145
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• 2005

The desulfurization abilities using GC/microreactor have been examined for $CuO-Fe_2O_3$ sorbents with respect to calcination temperatures of 700, 900 and $1,100^{\circ}C$. CuO was used as a main active component, $Fe_2O_3$ was used as an additive one and 25 wt% $SiO_2$ was used as a support. The desulfurization reaction temperature was $500^{\circ}C$ and the regeneration reaction temperature was $700^{\circ}C$. From the XRD results, the $CuFeO_2$ compound has been observed for the fresh sorbent calcined at $1,100^{\circ}C$ and the $CuFeS_2$ compound for the reacted sorbent calcined at $1,100^{\circ}C$. By the BET results, however any significant differences among sorbents calcined at the three different temperatures of 700, 900 and $1,100^{\circ}C$ haven't been observed. Especially CFS1 (CuO : $Fe_2O_3$ : $SiO_2$=67.5 wt% : 7.5 wt% : 25 wt%) sorbent calcined at $1,100^{\circ}C$ maintained about 10 g sulfur/100 g sorbent for 100 cycles by the cyclic test.