• Food Science of Animal Resources
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• v.22 no.1
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• pp.44-49
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• 2002

The effect of citric acid and sodium chlorite(NaClO$_2$) mixtures at 100, 200 and 500 ppd(w/v) on the growth of microorganisms from broiler thigh surface was investigated. Absorbance and aerobic plate counts(APC) of inoculated nutrient broth refrigerated storage at 4∼5$^{\circ}C$ were measured after each additive was added. APC on thigh surface after immersion in each selected solution was enumerated during storage at 4∼5$^{\circ}C$ Absorbance of all citric acid and sodium chlorite mixture(0:100, 25:75, 50:50, 75:25 and 100:0, w/w) except 200 and 500 ppm of 100:0 at Day 0 were lower than the control during storage (p<0.05). And higher concentration of mixture tended to have lower absorbance. APC on thigh surface treated with 500 ppm citric acid and sodium chlorite mixture at 50 : 50 and 75 : 25 ratio were lower than others (p<0.05). Similar antimicrobial activity of additives was found in nutrient broth and on broiler thigh surface.

• Journal of IKEEE
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• v.13 no.2
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• pp.194-199
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• 2009

In this study, ultra high-voltage (170kV AC), reliable 80pF mica capacitors for partial discharge system application were investigated. For capacitors design, Program was developed to sampling of series and parallel parameters. Mica was used as the dielectric of the capacitors. Using the conservative design rule, over 3 individual 50$\mu$m thick mica sheets with a size of 30mm$\times$35mm were used with lead foils to form a parallel capacitor element and 20 mica sheets were interleaved with lead foils to form a series stack of parallel capacitor element to meet the requirements of the capacitors. The dimension of the fabricated 80pF capacitor for 17kV AC were 90mm$\times$90mm. The high-frequency characteristics of the capacitance (C) and dissipation factor (D) of the developed capacitors were measured using a capacitance meter. The developed capacitor exhibited C of 79.5pF, had D of 0.001% over the frequency ranges of 150kHz to 50MHz, had a self-resonant frequency of 65MHz.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.3
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• pp.1-8
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• 2008

Effects of annealing process in a reduction ambient on thermoelectric properties of the $(Bi,Sb)_{2}Te_3$ thin films prepared by thermal evaporation have been investigated. With annealing at $300^{\circ}C$ for 2 hrs in a reduction ambient(50% $H_2$+50% Ar), the crystallinity of the $(Bi,Sb)_{2}Te_3$ thin films were substantially improved with remarkable increase in the grain size. Seebeck coefficients of the $(Bi,Sb)_{2}Te_3$ thin films increased from$\sim90{\mu}V/K$ to $\sim180{\mu}V/K$ with annealing in the reduction ambient due to decrease in the hole concentration. Power factors of the $(Bi,Sb)_{2}Te_3$ thin films were remarkably improved for $5\sim16$ times with annealing in the reduction atmosphere. After annealing in the reduction ambient, a $(Bi,Sb)_{2}Te_3$ evaporated film exhibited a maximum power factor of $18.6\times10^{-4}W/K^{2}-m$.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.139-146
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• 2004

A bacterium producing alkaline cellulase was isolated from soil, leaf mold and compost, and was identified as alkalophilic Bacillus sp. HSH-810 by morphological, cultural and biochemical determination. The optimum cul-ture condition of Bacillus sp. HSH-810 for the growth and alkaline cellulase production was $30^{\circ}C$ and pH 10.0. The maximum alkaline cellulase production was obtained when 1.0%(w/v) CMC, 0.5%(w/v) peptone, 0.02%(w/v) $CaCl_2$ and 0.02(w/v) $CoCl_2$ were used as carbon source, nitrogen source and mineral source, respectively. The optimum pH and temperature of the enzyme activity were pH 10.5 and $50^{\circ}C$, respectively. This enzyme was fairly stable in the pH range of 6.0-13.0 and at $50^{\circ}C$. For the effect of surfactants, the activity of alkaline cellulase was stable in the presence of sodium-$\alpha$-olefin sulfonate (AOS), sodium dodecyl sulfonate (SDS), Tween 20 and Tween 80, but inhibited by the presence of 0.1 linear alkyl-benzene sulfonate (LAS) sig-nificantly.

• Journal of the Korean Chemical Society
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• v.41 no.6
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• pp.313-319
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• 1997

Diazidophenylmethane derivatives(X: p-H, $p-OCH_3,\;p-F,\;p-CH_3$) were synthesized and the rate constants of hydrolysis of diazidophenylmethane derivatives were determined by UV spectrophotometry in 50:50(v/v) aqueous methanol at 25$^{\circ}C$. On the basis of rate equation, substituent effect, activation parameters, solvent effect, salt effect, and product analysis, it may be concluded that the hydrolysis of diazidophenylmethane derivatives proceed through $S_N2_CA$ mechanism below pH 2.0, while above pH 12.0 through $S_N2$ mechanism, and in the range of pH from 2 to 12 through $S_N1$ mechanism respectively.

• Korean Journal of Environment and Ecology
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• v.8 no.1
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• pp.74-77
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• 1994

To examine the effects of gibberelin treatment on seed germination of five Viola species - Viola variegata, Viola dissecta var, chaerophylloides, Viola collina, Viola hirtipes and Viola manshrica - in Wonju district, pretreated seeds of five species were sowed on Jiffy strips with mixed soil(sand： peat moss： perlite： vermiculite, 1:1:1:1, v/v) in 25, May 1994. Seeds were soaked in 5, 25, 50ppm gibberelin solution and ground water during 24 hours. Seed germination rate was measured and compared among species and treatments. Seed germination rate of Viola hirtipes was differed higly significant among pretreatments, but those of other species did not significant at 5of level. In general GA$_3$pretreatment raised seed germination rate of 5 Viola species, and proper concentration of GA$_3$was 25~50ppm.

• Journal of Energy Engineering
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• v.2 no.2
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• pp.200-207
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• 1993

A methanol reformer was designed and fabricated using a CuO-ZnO low temperature shift catalyst, and its operation characteristics have been studied for the phosphoric acid fuel cell (PAFC) power generation system. The type of reactor was annular Methanol was consumed both for heating and for reforming fuel. Contents of carbon monoxide produced from the reformer increased as the reaction temperatures increased, but decreased as the mole ratios of water to methanol(H$_2$O/CH$_3$OH) increased. At steady state operating conditional, temperature profile of the catalytic reactor of the reformer was well coincide with the model equation, and it took 50 minutes from start to the rated condition of the reformer. When the system was operated at 4/4 and 1/4 of load, thermal efficiencies of the system were 72.3% and 77%, respectively. When the PAFC system was operated with reformed gas in the range of 62 V-37.6 V and 0-147 A, the trend of I-V curve showed a typical fuel tell characteristic. At steady state condition, the flow rates of reforming and combustion methanol were 88.1 mol/h and 50.1 mol/h, respectively.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.213-218
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• 1997

Total lipid were extracted from the eggs, livers, intestines, muscles, and testis of Fugu xanthopterus. The fatty acid composition of total lipid was analyzed by gas liquid chromatography. Proximate percentage of total lipid from the samples was shown to be ; 81.72% in the livers, 14.53% in the intestines, 12.63% in the eggs, 0.85% in the muscles, and 1.74% in the testis. Toxins(tetrodotoxins) were completely removed from the liver of Fugu xanthopterus with 1% acetic acid/methanol solution before total lipid was extracted with CHCI3:methanol solution(2:1, v/v). The toxicity left in the total lipid was checked using mice. The content of DHA in each tissues of Fugu xanthopterus was the most abundant in muscle(32.4%), followed by liver(23.0%), intestine(26.7%) and testis(15.4%). The level of total polyenoic acids comprising DHA was more abundant in muscle(57.4%) than in the liver(50.9%).

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.2
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• pp.81-87
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• 2001

Populus euramericana and Betula platyphylla var. japonica have been identified as possible species for use for phytoremediation of landfills. To identify the capacity of waste leachate absorption in Populus euramericana and Betula platyphylla var, japonica, four different treatments were applied to these seedlings: leachate solution (100% leachate), 50% dilution (50% leachate: 50% water, v/v) and 25% dilution (25% leachate: 75% water, v/v) were applied to these two species. After the experiment, concentrations of heavy metals in tree biomass were analyzed by Inductively Coupled Plasma emission spectrometer (ICP). These two species can take up the hazardous parts of the leachate such as heavy metals. Especially, these species showed good absorption capacity of Al, Cr, and Fe elements. The result of this study suggested that these two species can take up the toxic materials through their roots and transport them to stems or leaves.

• Korean Journal of Environment and Ecology
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• v.9 no.1
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• pp.56-61
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• 1995

To examine the effects of gibberelin treatment on seed germination of six wild herbaceous species -Dicentra spectabilis, Aster pekinensis, Agastache rugosa, Elsoholtzia ciliata, Boehmeria tricuspis and Pulsatillia cerrma var. chaerophyiloides - in Kangwon-do, pretreated seeds of five species were sowed on plastic pots with mixed soil(sand：peat moss：perlite： vermiculite, 1：1：1：1, v/v) in 23,April 1995. Seeds were soaked in 25,50 ppm gibberelin solution and ground water during 24 hours. Pretreated seeds of Pulsatiilia cerrma var. chaerophylloides were sowed on nursery soil in 1, June 1995. Seed pretreatments in 31, May 1995 were same method. Seed germination rate was measured and compared among species and treatments. Seed germination rate of Dicentra spectabilis, Agastache rugosa and Elsoholtzia ciliata was differed higly significant among pretreatments ,but those of that of Aster pekinensis, Boehmeria tricuspis and Pulsatillia cerrma var chaerophylloides did not significant at 5% level. Gibberelin pretreatment raised seed germination rate of Dicentra spectabilis and Agastaohe rugosa and proper concentration of GA$_3$ was 25ppm and seed germination rate of Elsoholtzia ciliata was highest at GA$_3$ 50ppm plot. The utilization of wild herbaceous species were discussed.