• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.2
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• pp.137-143
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• 2010

Complete dryness inside the stator is a necessary and sufficient condition for the leak test. Microcracks caused by high cycle fatigue due to operation are generated in stator windings, and they are interrupted by water molecules during the leak test. For this reason, during leak test, the wrong value is indicated when there are no leaks in stator windings. Generator manufacturers presents unique dryness judgment criteria for the leak test, but there is no actual criterion that accurately indicates the dryness point for the leak test. The reason is because stator winding has a complex structure and the absence of effective dryness equipment in power plants. This paper proposes a dryness judgment criterion to evaluate if inside the stator winding is dried completely and presents experimental results.

• Korean Journal of Human Ecology
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• v.6 no.1
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• pp.27-34
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• 2003

We investigated the bacterial and chemical retting conditions of ramie grown in Hansan. Bacterial retting was done in troughs at a temperature of 30${\pm}$2$^{\circ}C$ for 1, 2, 3, 4, 5, 6 and 10 days. Chemical retting(CR) was done at the different conditions using sodium silicate (Na$_2$SiO$_3$), sodium carbonate(Na$_2$CO$_3$) and sodium hydroxide(NaOH) as alkali solutions. The retting solution was boiled during 1. 2, 4 and 6 hours respectively at the different concentration(0.5, 2.0, 4.0, 6.0. 8.0 %) with decorticated ramie stems submerged in it. The treated ramie was then rinsing with running tap water thoroughly, which was further soaker in 0.5% acetic acid (v/v) solution for three minutes and washed thoroughly with distilled water. Finally ramie was dried for 2 hours in vacuum oven at 100 $^{\circ}C$. To know change of ramie fiber characteristics retted at the different conditions, weight loss, fiber bundle strength were tested and color, texture, luster etc. were also sensually evaluated. The results were as follows. $.$ Weight loss of ramie retted in each alkali solutions were about 10%, 20% and 30% in sodium silicate, sodium carbonate and sodium hydroxide, respectively. $.$ Chemical retting was faster than bacterial retting, but the color of chemically retted ramies were worse than that of bacterially retted ramies. $.$ The combination of bacterial and chemical processing showed some merits. A combination of either 2 or 3 days of bacterial and then chemical retting might provide the best quality ramie. $.$ Ramie fiber became cottonized ramie when retted in 8% NaOH solution for 6-8hours.

• Journal of Life Science
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• v.10 no.3
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• pp.229-235
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• 2000

The absorption characteristics of Korean yam powder according to different drying methods were investigated. The physical properties of yam powder by different drying methods were showed the biggest porosity in freeze drying sample, while the smallest in hot air drying sample. No difference was founded in proximate compositions of yam powder by various drying methods. The amount of total phenolic compound and Vit C were showed the bigger decrement in freeze dried sample than other drying methods. The time reaching to equilibrium moisture content were determined in 12 days. Monolayer moisture contents were predicted to 0.0508∼0.0588 by BET equation and 0.0705∼0.0811 g H2O/g solid by GAB equation. BET equation for isothermal absorption curve showed over 0.95 R-square for every drying methods. GAB equation showed over 0.99 in vacuum and freeze drying but a poor R-square in hot air drying.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.6-14
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• 1991

Intramuscular lipid of longissimus dorsi muscle(white muscle), soleus muscle(red muscle) and cardiac muscle were autooxidized at $37^{\circ}C$ for 20 days, and the rancidity development and the effect of various factors on rancidity development were compared. Although the myoglobin content of red muscle was about 5 times as high as that of white muscle, the degree of autooxidation occurred in intramuscular lipid did not differ between red muscle and white muscle, when they had the same lipid content. Accordingly, it was suggested that the susceptibility of muscle tissues to lipid oxidation depends mainly on the lipid content of muscle tissue, regardless of muscle types. Lipid oxidation was not a major quality deterioration for dried-pork product, when it contained adequate amount of sodium nitrite and was air-tight vacuum-packed.

• Analytical Science and Technology
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• v.26 no.1
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• pp.61-66
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• 2013

The activity of an antimicrobial peptide, protegrin-1, on the well-aligned lipid bilayer deposited on a thin coverglass plate was investigated by $^2H$ solid-state NMR spectroscopy. Orientational distribution and molecular motion in the lipid bilayer were determined from $^2H$ solid-state NMR spectrum. Reorientational motion of lipid molecules in the vacuum-dried state was found to be small but their orientational distribution was not able to be determined. As storage times were longer, the order of the alignment of lipid molecules in the lipid bilayer and percentages involved in the toroidal pore structures increased. We found that much longer time is required to get the equilibrium state of the peptide-lipid mixture under our experimental condition for investigating the action of the antimicrobial peptide like protegrin-1 on the lipid bilayers deposited on the thin coverglass plates.

• Microbiology and Biotechnology Letters
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• v.5 no.4
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• pp.171-175
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• 1977

A microbial strain capable of producing lactic acid was isolated and identified as Streptococcus faecium. During the incubation of the isolated bacterium in a synthetic medium (Petterson broth), the optimal temperature was 36 to 39$^{\circ}C$ and the cell concentration at stationary growth phase was 2.1${\times}$10$\^$8/ viable cells/ml. When it was dried in vacuum and diluted with avicel, the Viability of Streptococcus faecium in physiological saline solution was decreased to 80％ after incubation for 48 hr at 37$^{\circ}C$, whereas the viability was above 90％ after incubation for 1 hr at 40$^{\circ}C$ and the viability in M buffer solution (pH 4.5∼9.0) at 37$^{\circ}C$ was above 95％. From these data it was concluded that the isolated microbe must be adoptible for pharmaceutical preparation such as solid dosage form.

• Journal of the Korean Ceramic Society
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• v.44 no.8
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• pp.437-444
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• 2007

The broth solution was prepared by the mixing of an uranyl nitrate, THFA, PVA, and water. The uranium concentration of the broth solution was $0.5{\sim}0.8$ mole-U/L and the viscosity of it was $30{\sim}80cSt$. The droplets of this broth solution were farmed in air and ammonia by the vibrating nozzle with the frequency of 100 Hz at the amplitude of $100{\sim}130V$. The diameter of the droplet was about $1900{\mu}m$ from using the nozzle diameter of 1 mm. The diameter of the aged gel was about $1400{\mu}m$ after aging in ammonia solution at $60{\sim}80^{\circ}C$, and the dried gel with the diameter of about $900{\mu}m$ was obtained after drying at room temperature or partially vacuum condition. The diameter of the calcined $UO_3$ microsphere after calcination at $600^{\circ}C$ appeared about $800{\mu}m$ in air atmosphere. Although the droplets of the same sizes were formed, the calcined microspheres of different sizes were manufactured in the case of the broth solutions of the different uranium concentration. The droplets of the desired diameters were obtained by the change of the nozzle diameters and the broth flow rates.

• Journal of Environmental Health Sciences
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• v.20 no.1
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• pp.39-53
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• 1994

This study aims to investigate organic compounds and its toxicity by Ames test and chromosomal aberration in the water of the Nak Dong River. Six sampling sites such as Goryung, Hagueun, Maelie, Duksan, Haedong and Myungiang were selected for these pur15oses. 200 l water samples were absorbed on XAD-2 resin columns (2.5X30cm), eluted with organic solvents mixture of acetone: cyclohexane and then dried under vacuum condition. The extracts from the XAD-2 resin was injected into GC/MS and 184 organic compounds were identified such as aldehydes, aromatic compounds, ketones, phenols, hydrocarbons, alcohols, carboxylic acids, alkanes and some unknowns. The US EPA priority pollutants such as naphthlene, bis(2-ethylhexyl)phthalate and other pollutants, 1,2-diethyl benzene, 1,2,3,4-tetrahydronaphthalene and cyclohexanol were detected in these samples. The concentration of chemical pollutants such as 1,2-diethyl benzene, nephthalene, 1,2,3,4-tetrahydronaphthalene, bis(2-ethylhexyl)phthalate and cyclohexanol were ranged into 1.228 $\mu$g/l, 298 $\mu$g/l, 30.191 $\mu$g/l, 1.147 $\mu$g/l and 2.839 $\mu$g/l, respectively. The mutagenic activity of XAD-2 extracts were tested on Salmonella typhimurium TA 98, TA 100, TA 1535 and TA 1537 and then exhibited strong mutagenic activity against S. typhimurium TA 98 and TA 100 in the presence of S$_9$. Amon them, bis(2-ethylhexyl)phtalate and 1,2-diethyl benzene showed the most strongest mutagenic activity against S. typhimurium TA 98 and TA 100 in the presence of S$_9$. On the other hands, chromosomal aberration of XAD-2 extracts in the human blood cells were not occurred by the sampling water at Goryung, Hagueun, Maelie and Duksan, Chromosomal aberration were also not occurred by the each concentration of 0.05, 0.1 amd 0.3 mg/l of each 1,2-diethyl benzol, bis(2-ethylhexyl)phthalate, naphthalene, phenol, cyclohexanol and benzothiazol test solution.

• Journal of Sensor Science and Technology
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• v.7 no.3
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• pp.218-224
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• 1998

2nO and $Al_{2}O_{3}$ powder were weighed in 1 : 1 mole ratio and ball-milled in ethanol for 3 h. Dried mixture were pressed and then sintered at $900^{\circ}C{\sim}1200^{\circ}C$ for 3 h in vacuum($3{\times}10^{-5}$ Torr). According to XRD, remnant ZnO and $Al_{2}O_{3}$ not converted to $ZnAl_{2}O_{4}$ were observed up to $1100^{\circ}C$, which were completely changed to$ZnAl_{2}O_{4}$ ternary compound at $1200^{\circ}C$. Optical bandgap is calculated at 4.75 eV. With increasing sintering temperature, PL spectrums shifted to shorter wavelengths and are appeared 430nm at $1200^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.675-680
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• 1990

A near-infrared reflectance spectroscopic(NIRS) method which has been recently developed for a non-destructive method for measuring ingredients in foods and agricultural products especially was evaluated for the determination of capsanthin, total sugar, capsaicin and moisture contents in Korean domestic red peppers. A multiple linear regression analysis with the data obtained by standard-laboratory methods(capsaicin by GC, capsanthin by Colorimetry, total sugar by HPLC and moisture by Vacuum drying method) and NIRS method was carried out to make a calibration. The accuracy of the NIRS method was found to be adequate when the standard-laboratory values for a set of sample that were not included in the calibration, were compared. It is concluded that the NIRS method is suitable for the determination of total sugar and capsanthin.