• 한국초전도학회:학술대회논문집
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• v.10
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• pp.207-210
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• 2000

Properties of SrTiO$_3$ thin films were characterized under the influence of an applied dc voltage utilizing a gold resonator with a flip-chip capacitor. The measurements were performed at microwave frequency ranges and low temperatures cryogenic temperatures. The dielectric constant of 830 and the low loss tangent of 6X10$^{-3}$ at 3.64 GHz were observed at 90 K and 100 V. The quality in the SrTiO$_3$ film was presented in terms of fractional frequency under the bias voltages and cryogenic temperatures.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.90-92
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• 2004

Suspension effect has been studied by using superconductor of BiPbSrCaCuO ceramics containing $Ag_2O$. It has been cleared that $Ag_2O$ acts as pinning center which plays an important role to the suspension effect. Magnetic repulsive force which affects a superconductor located in magnetic flux from toroidal magnet has been investigated. It has been concluded that the suspension effect arises from the interaction between the pinning effect and the diamagnetic effect.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.293-296
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• 1988

Stability of spheroplasts prepared from Saccharomyces cerevisiae D-71, a thermophilic strain and Zygosaccharomyces rouxii SR-S, an osmotolerant strain were studied. Stability of spheroplast from Saccharomyces cerevisiae D-71 was highest in 0.8M KCI and 1.0M sorbitol ; that from Zygosaccharomyces rouxii SR-S was highest in 0.4M KCI and mannitol and that from both strains was less than 10% for sonic oscillation at 20Kc for 60 sec. In centrifugation at 10000 x g for 10 min., stability of spheroplast from Saccharomyces cerevisiae D-71 was 93% and that from Zygosaccharomyces rouxii SR-S was 84%. Breakage of spheroplast from Saccharomyces cerevisiae D-71 was 99% and that from Zygosaccharomyces rouxii SR-S was 55% for UV irradiation with 15W UV lamp at a distance of 20 cm for 60 min.

• Applied Biological Chemistry
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• v.32 no.2
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• pp.91-97
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• 1989

For the effective use of soymilk residue (SR), by-product of soymilk production, barley Doenjang was manufactured. As the results, the contents of reducing sugar increase3 for 50 days in all samples and decreased thereafter. The contents of amino nitrogen increased prominently for 50 days, but increasing ratio was slightly slowdowned thereafter. The higher mixing ratio of SR, the less were the contents of reducing sugar and amino nitrogen. The contents of total acid also increased prominently for 30 days, but were slowdowned thereafter and the differences among all treatments were negligible. As the mixing ratio of SR was increased, the lightness and the yellowness increased and the redness decreased in 80days aged samples. In sensory evaluation of 90 days aged samples, the control was the best in soy sprout Doenjang soup. As the mixing ratio of SR increased, the taste was dropped slightly but no significant differences were obtained among sample A(barley koji 100, soybean 75, SR 25), B(barleykoji 100, soybean 50, SR 50) and C(barley koji 100, soybean 25, SR 75). In the original taste of Doenjang, the control was the best and as the mixing ratio of SR was increased, the point was dropped but these were no significant differences among control, A and B, and among A, B and C, and among B, C and D(barley koji 100, soybean 0, SR 100).

• Applied Biological Chemistry
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• v.32 no.2
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• pp.98-103
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• 1989

For the effective use of soymilk residue (SR), by-product of soymilk production, rice Doenjang was manufactured. As the results, the contents of reducing sugar were increased till $40{\sim}50days$ in all samples and decreased thereafter during aging of the mash. The contents of amino nitrogen were prominently increased till 50days, but increasing ratio was slightly slowdowned thereafter. The higher mixing ratio of SR, the less were the contents of reducing sugar and amino nitrogen. The contents of total acid were also prominently increased till 30days, but were slowdowned thereafter and the differences among all treatments were small. As the mixing ratio of SR was increased, the lightness and the yellowness were increased and the redness was decreased in 80days aged samples. In sensory evaluation of 90days aged samples, control was the best in soy sprout Doenjang soup. As the mixing ratio of SR was increased, the taste was dropped slightly but no significant differences were obtained between control and sample A (rice koji 100, soybean 75, SR 25), and among A,B(rice koji 100, soybean 50, SR 50). C(rice koji 100, soybean 25, SR 75) and D(rice koji 100, soybean 0, SR100). In the original taste of Doenjang, the control was the best and as the mixing ratio of SR was increased, the point was dropped but there were no significant differences between control and A, and among A, B and C, and among B, C and D.

• Journal of the Korean Vacuum Society
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• v.11 no.1
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• pp.1-7
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• 2002

We deposited $Ba_{0.5}Sr_{0.5}TiO_3$(BST) thin-films on Pt/Ti/$SiO_2$/Si substrates using RF magnetron sputtering method. A Substrate temperature was fixed at room temperature, while working gas flow ratio and RF Power were changed from 90:10 to 60:40 and 50 W, 75 W respectively. Also after BST thin films were deposited, we performed annealing in oxygen atmosphere using Rapid Thermal Annealing. For capacitor application we deposited Pt using E-beam evaporator of UHV system. In a structural property study through XRD measurement we found that crystallization depends on annealing rather than working gas ratio or and RF Power. Electrical properties showed relatively superior characteristic on the annealed sample with 50 W of RF Power.

• Journal of Radiation Protection and Research
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• v.24 no.1
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• pp.9-15
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• 1999

In order to separate $Sr^{2+}$ selectively from environmental sample solutions containing $Ca^{2+}$, supported liquid membranes(SLM) were prepared and their characteristics of separation were investigated. The contents of carriers, DC18C6 and DNNS, in SLM affected the permeabilities of metal ions and selectivities of $Sr^{2+}$. The selectivity of $Sr^{2+}$ reached to 93.3% in a SLM with 0.1 M DC18C6 and 25 mM DNNS. When the ratio of $Sr^{2+}$ to $Ca^{2+}$ concentration in the feed solution was in the range of 1/25 to 1/50, the selectivity of $Sr^{2+}$ was greater than 90 %. Therefore, it is considered that the SLM prepared in this study is capable of treating environmental sea-water samples for strontium measurement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1115-1121
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• 2007

[ $Bi_2Sr_2Ca{_{n-1}}Cu_nO_x$ ](n=0,1,2) thin fans have been fabricated by co-deposition at an ultra-low growth rate using ion beam sputtering(IBS) method. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

• Polymer(Korea)
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• v.29 no.2
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• pp.166-171
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• 2005

EPDM (ethylene propylene diene monomer)/silicone rubber blends were prepared and the influence of a compatibilizer and thermal aging on the properties of the blends was investigated. The blends of which the compositions were varied in the range of 90/10 through $10/90\;wt\%$ were melt mixed by using a Brabender Plasticoder (internal mixer) and were vulcanized by a hot press. The morphology of the vulcanized EPDM/SR blends was examined by scanning electron microscopy (SEM). After the thermal Aging for 24, 48, 96 hrs at $100^{\circ}C$ in an air oven, hardness, tensile strength, elongation and contact angle of the blends were investigated. From the result of the morphology, it was confirmed that the domain size of the blends containing the compatibilizer was reduced. As the increase of the thermal aging time, hardness and tensile strength of the blends decreased but elongation and contact angle increased.

• 전기의세계
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• v.14 no.3
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• pp.28-33
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• 1965

This experiment is based on "the feasible improvement studies for an eliminating device of the static electricity which applies the ionizing effect of beta radiation." In order to accomplish this object, the following problems were necessarily considered to investigate and to determine. The efficiency of the elimination of static electricity was determined by means of measuring the ion current between electrically charged plates with micro-ammeter. The effects of various factors, i.e., the distance between charged plate and radiation source, the activity of radiation source, the electric otential and the area of the charged plate, the shape of the source housing, the lining of backscattering material (Pb) on the source housing surface and blowing of ionized air, on the static electricity eliminating efficiency were studied. The beta radiation sources used in this experiment were S$^{35}$ and Sr$^{90}$ -Y$^{90}$ . It was revealed that ion current increased with source activity, the electric potential and area of the plates, the lead (Pb) lining on the surface of the source housing and the velocity of the ionized air blowing. As one could expect the S$^{35}$ was more effective to increase the ion current since it is known to be a higher specific ionization source than Sr$^{90}$ -Y$^{90}$ . The detailed result and performance of the eliminating device of the static electricity are described here.ibed here.