• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.136-141
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• 1988

Susceptibility of a thermophilic strain (D-71) of Saccharomyces cerevisiae and an osmotolerant strain (SR-S) of Zygosaccharomyces rouxii to Zymolyase-20T were studied in various renditions. Content of glucan and mannan in cell wall of Saocharomyces cerevisiae D-71 were 14.5% and 14.8%, and Zygosaccharomyces rouxii SR-S were 24.0% and 19.0%, respectively. Susceptibility of Saccharomyces cerevisiae D-71 cultured in Wickerham synthetic medium containing 0.5% of methionine and 0.1% of glucose to Zymolyase-20T was 66%, and $K_2$HPO$_4$ and aminobenzoic acid were greatly effective to susceptibility. Susceptibility of Zygosaccharomyces rouxii SR-S cultured in Wickerhnin synthetic medium containing 0.5% of peptone, 0.15% of methionine and 0.l% of glucose to Zymolyase-20T was 80%, and KI and pyridoxine were greatly effective to susceptibility. Susceptibility of Saccharomyces cerevisiae D-71 stationary cultured in YMPG medium at $25^{\circ}C$ for 12 hours was 16o1e and Zygosaccharomyces rouxii SR-S stationary cultured in YMPG medium at $25^{\circ}C$ for 30 hours was 82%.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.2
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• pp.101-112
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• 2016

This study investigated the removal of Sr, which was one of the high radioactive nuclides, by adsorption with Barium (Ba) impregnated 4A zeolite (BaA) from high-radioactive seawater waste (HSW). Adsorption of Sr by BaA (BaA-Sr), in the impregnated Ba concentration of above 20.2wt%, was decreased by increasing the impregnated Ba concentration, and the impregnated Ba concentration was suitable at 20.2wt%. The BaA-Sr adsorption was added to the co-precipitation of Sr with $BaSO_4$ precipitation in the adsorption of Sr by 4A (4A-Sr) within BaA. Thus, it was possible to remove Sr more than 99% at m/V (adsorbent weight/solution volume)=5 g/L for BaA and m/V >20 g/L for 4A, respectively, in the Sr concentration of less than 0.2 mg/L (actual concentration level of Sr in HSW). It shows that BaA-Sr adsorption is better than 4A-Sr adsorption in for the removal capacity of Sr per unit gram of adsorbent, and the reduction of the secondary solid waste generation (spent adsorbent etc.). Also, BaA-Sr adsorption was more excellent removal capacity of Sr in the seawater waste than distilled water. Therefore, it seems to be effective for the direct removal of Sr from HSW. On the other hand, the adsorption of Cs by BaA (BaA-Cs) was mainly performed by 4A within BaA. Accordingly, it seems to be little effect of impregnated Ba into BaA. Meanwhile, BaA-Sr adsorption kinetics could be expressed the pseudo-second order rate equation. By increasing the initial Sr concentrations and the ratios of V/m, the adsorption rate constants ($k_2$) were decreased, but the equilibrium adsorption capacities ($q_e$) were increasing. However, with increasing the temperature of solution, $k_2$ was conversely increased, and $q_e$ was decreased. The activation energy of BaA-Sr adsorption was 38 kJ/mol. Thus, the chemical adsorption seems to be dominant rather than physical adsorption, although it is not a chemisorption with strong bonding form.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.1
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• pp.29-35
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• 2000

Luminescent characteristics of SrS:Cu,X TFeL devices fabricated by electron-beam deposition system were studied. The SrS powders were used as the host materials and Cu, $CuF_2,\;Cu_2S$ or CuCl powders were added as the luminescent center. The emission spectra of the SrS:Cu,X TFEL devices strongly depended on coactivators. The luminance($L_{40}$) and efficiency(${\eta}_{20}$) of SrS:$Cu_2S$ TFEL device were 1443 cd/$m^2$ and 2.44 lm/w, respectively. Green color was observed from this TFEL device. The luminous efficiency of SrS:$Cu_2S$ TFEL device was higher than that of ZnS:Tb TFEL device, and it also could be good green phosphors for TFEL devices. The luminance($L_{40}$) and efficiency(${\eta}_{20}$) of SrS:CuCl TFEL device were 262 cd/$m^2$ and 0.26 lm/w, respectively. Blue color was emitted from this TFEL device.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.3
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• pp.453-467
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• 1998

This study helps to clarify conflicting reports by comparing the physical properties and accuracy of complete denture processed by the pack and press technique, continuous- pressure injection technique(SR-Ivocap system) and Mark press technique. The 6 different specimens have been evaluated using the SEM, Impact test, DSC (Differential Scanning Calorimetry) and DMTA (Dynamic Mechanical Thermal Analysis). Each sample was made of SR-Ivocap resin and QC-20 resin by different processing methods. The results were as follows ; 1. As the result of the observation on the fracture surface of resin by use of SEM, sample SR-Ivocap resin cured by continuous pressure injection method showed the most homogeneous structure. This is why molecules in SR-Ivocap resin have no orientation. 2. As the result of the Impact test in order to measure the deformity, fracture energy and impact resistance of resin, the samples with QC-20 acrylic resin and SR-Ivocap resin cured by continuous pressure injection method were exellent. 3. In consequence of measuring ${\alpha}$-glass transition temperature by use of DSC on the basis of temperature change, the glass transition temperatures of sample QC-20 resin cured by pack and press method and sample SR-Ivocap resin cured by continuous pressure injection method were very similar. Thus volumetric stability could not be evaluated only by glass transition temperature. 4. In comparing volumetric stability data by DMTA, the glass transition temperature(Tg) showed $137.88^{\circ}C$ at sample QC-20 resin cured by pack and press method and $139.78^{\circ}C$ at sample SR-Ivocap resin cured by continuous pressure injection method. Therefore sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in the dimensional stability at high temperature. 5. In comparing storage modulus data by DMTA, the storage modulus of sample SR-Ivocap resin cured by continuous pressure injection method was higher than that of sample QC-20 resin cured by pack and press method. So. sample SR-Ivocap resin cured by continuous pressure injection method seems to be superior to sample QC-20 resin cured by pack and press method in impact strength.

• 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.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.6
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• pp.527-530
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• 2007

[ $SrTiO_3$ ] red phosphors doped with Pr, Er and Al were synthesized by solid state reaction method. Three emission peaks in photoluminescence spectra of the $SrTiO_3:Eu$ Phosphors were observed at 583 nm, 610 nm and 685 nm. The emission peaks in the $SrTiO_3:Eu$ phosphors were associated with charge-transfer states. The decrease of photoluminescence intensity in $SrTiO_3:Eu,Al$ phosphors with doping Al ions was interpreted by the change of charge-transfer states.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.8
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• pp.17-23
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• 2002

The SrS:CuCl TFEL devices were fabricated by electron-beam deposition and the luminescent characteristics of the fabricated SrS:CuCl TFEL devices were studied. The SrS powder was used as the host materials and 0.05 ~ 0.6 at% of CuCl powder was added as the luminescent center. The deposition conditions of substrate temperature, electron beam current, and deposition rate were 500 $^{\circ}C$ , 20 ~ 40 mA, and 5 ~ 10 /sec, respectively The total thickness of the phosphor layer deposited was 6000 . The blue emission at low CuCl concentrations was observed from the luminescent centers of monomer, dimer, trimer, and tetramer, The bright greenish blue emission at high CuCl concentrations was observed from the dimer and trimer luminescent centers. The maxium luminance was observed from the SrS:CuCl TFEL devices doped with 0.2 at% of CuCl concentration and the threshold voltage, luminance(L$_{40}$ ), efficiency(η$_{20}$) and CIE coordinate obtained were 55 V, 728 cd/$m^2$, 0.49 lm/w, and (0.21, 0.33), respectively..

• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.822-826
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• 2008

We report the cathodoluminescence and aging properties of a series of green phosphors of formula $Sr_{1-x}M_xGa_2S_4$:Eu (x = 0.0-1.0, M = Ba or Ca) that have potential applications in field emission displays (FEDs). The series of phosphors was synthesized via NaBr-aided solid-state reactions in a flowing $H_2S$ stream. A low level ($\sim$20%) of Ba or Ca substitution for Sr in $SrGa_2S_4$:Eu maintains the orthorhombic phase of pure $SrGa_2S_4$:Eu phosphors. Further, a low level ($\sim$20%) of Ba or Ca substitution for Sr in $SrGa_2S_4$:Eu provides various green colors and sufficient brightness for FED applications. Substitution of Ba or Ca for Sr in $SrGa_2S_4$:Eu also improved the stability of the phosphor when it was operated under electron-beam irradiation of 5 kV.

• Korean Journal of Crystallography
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• v.7 no.2
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• pp.147-155
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• 1996

Floating Zone Image furnace with halogen lamps as heat source has been made and applied to the growth of high-Tc superconductor Bi2Sr2CaCu2O8. The manufactured crystal growth equipment is composed of holder unit for setting the halogen lamps at the focal point of the elliptical mirror, image furnace with maximum temperature of 1800℃ with 1kW halogen lamps, cooling unit, feeding unit for supplying source material to the molten zone, pulling unit for crystal growth, and the control unit in the range of 2mm/hr -40 mm/hr vertical movement and 15rpm - 12rpm rotation. Bi2Sr2CaCu2O8 fibers have been grown with 300W halogen lamps and characterized with XRD, SEM and EDS. The growth condition was air atmosphere, growth speed 3∼4mm/hr, rotation speed of upper and lower part 20∼25 rpm. The fiber was composed of 20∼25 rpm matrix phase and secondary phases such as (Sr,Ca)CuO2 and (Sr,Ca)2CuO3.

• Elastomers and Composites
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• v.40 no.4
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• pp.266-271
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• 2005

In this work, the thermal stability factors, such as the thermal decomposition temperature, decomposition activation energy ($E_d$), and char yield, were measured to investigate the effect of silicone rubber (SR) content on the thermal stabilities of EPDM/SR blends. As a result, the thermal decomposition curve of EPDM/SR blends was similar to the neat EPDM rubber at 10 wt% SR and the thermal decomposition temperature increased above this content. The $E_d$ value of EPDM rubber initially decreased and then was constant above 20 wt% weight losses. The $E_d$ of EPDM/SR blends was higher than that of the neat EPDM rubber and then decreased with increasing the weight loss when the SR content was in the range of 10-20 wt%. Whereas the $E_d$ of the blends was lower than that of the EPDM rubber and then decreased with increasing the weight loss when 30 wt% SR was added. The char yield at $800^{\circ}C$ increased with increasing the SR content, because the decomposition of silane groups in the backbone was capable of forming a silane-rich residue after the initial stage of thermal degradation, which finally prevents further heat transfer and diffusion in the blends.