• 한국전기화학회:학술대회논문집
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• 2004.10a
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• pp.33-33
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• 2004

• Journal of the Korea Institute of Military Science and Technology
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• v.2 no.1
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• pp.183-193
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• 1999

Semiconducting (Sr0.85Ca0.15)TiO3 ceramics were prepared by conventional powder synthesis techniques, and then alkaline metallic cations were diffused into the ceramic bodies. The threshold voltage of the ceramics increases with increasing diffusion time and the amount of diffused materials. The ceramics had boundary potential heights of 0.01 ~ 2.89 eV, while their boundary resistance ranged from 2.2 $M{\Omega}$ to 120.4 $M{\Omega}$. Such electrical characteristics of the boundaries were correlated with the boundary structure of the ceramics obtained by transmission electron microscopy.

• Journal of the Korean Ceramic Society
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• v.34 no.2
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• pp.202-208
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• 1997

Bi-layered SrBi2Ta2O9(SBT) films were deposited on Pt/Ti/SiO2/Si sibstrates by rf magnetron sputt-ering at room temperature and then were annealed at 75$0^{\circ}C$, 80$0^{\circ}C$ and 85$0^{\circ}C$ for 1 hour in oxygen at-mosphere. The film composition of SrBi2Ta2O9 was obtained after depositing at room temperature and annealing at 80$0^{\circ}C$. Excess 20mole% Bi2O3 and 30 mole% SrCO3 were added to the target to compensate for the lack of Bi and Sr in SBT film. 200 nm thick SBT film exhibited and dense microstructure, adielectric constant of 210, and a dissipation factor of 0.05 at 1 MHz frequency. The films exhibited Curie temperature of 32$0^{\circ}C$ and a dielectric constant of 314 at that temperature under 100 kHz frequency. The remanent polarization(2Pr) and the coercive field(2Ec) of the SBT films were 9.1 $\mu$C/$\textrm{cm}^2$ and 85 kV/cm at an applied voltage of 3V, resspectively and the SBT film showed a fatigue-free characteristics up to 1010 cy-cles under 5V bipolar pulse. The leakage current density of the SBT film was about 7$\times$10-7A/$\textrm{cm}^2$ at 150 kV/cm. Fatigue-free SBT films prepared by rf magnetron sputtering can be suitable for application to non-volatile memory device.

• Journal of Radiation Protection and Research
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• v.14 no.1
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• pp.16-23
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• 1989

To obtain the basic data for protective roles and first-aid of radiation hazard, the present studies were carried out to evaluate the decontamination of radiostrontium by the First-Aid drugs. Each mouse was administered intraperitoneally dose of sodium alginate 5mg, $CaNa_3DTPA$ 8.4mg and saline 5ml following the internal contamination with 1 $\mu$Ci of strontium as $^{85}SrCl_2$. $^{85}Sr$ was determined by the radioactivity of body burden, urinary excretion, fecal excretion and organ distribution by Ge-detector and MCA. The results are summarized as follows. 1. Effective half life on whole body retention $^{85}Sr$ was determined at 33 hours. 2. The decontamination effect of First-Aid durgs on the body $^{85}Sr$ burden were increased $CaNa_3DTPA$ (4.7 times), sodium alginate (1.7 times) and saline (2.4 times) respectively. 3. Strontium were excreted through urine (35.4%), feces (64.4%) and other (0.2%). But on the $^{85}Sr$ excretion routes following First-Aid drugs treatment, strontium-85 mainly were excreted through urine after $CaNa_3DTPA$ and saline treatment, and was excreted through feces after sodium alginate treatment. 4. The organ distribution of strontium-85 is vertebra, femur, sternum and liver in order Finally, the extrapolations from these data to victims were suggested that the rapid administration of $CaNa_3DTPA$, sodium alginate and saline simultaneously were markedly increased the decontamination effects on the internal contamination of radiostrontium.

• Journal of Radiation Protection and Research
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• v.20 no.4
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• pp.255-263
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• 1995

Root uptakes of $^{54}Mn,\;^{60}Co,\;^{85}Sr\;and\;^{137}Cs$ by rice were studied through a greenhouse experiment in which the upper 20 cm of the culture box was filled with an acidic loamy-sandy soil and a mixed solution of the radionuclides was applied to the surface water on the soil 2 days before, and 5 different times after, transplanting. Percent uptakes of the radionuclides to rice tops varied $3.4{\sim}13.7%,\;0.03{\sim}0.1%,\;0.6{\sim}1.5%,\;0.02{\sim}0.15%$, respectively, with application time. Among radionuclides, soil-to-plant transfer factors decreased, on the whole, in the order of $^{54}Mn>^{85}Sr>^{60}Co{\geq}^{137}Cs$, and among plant parts, in the order of straw > chaff > hulled seed. Transfer factors $(m^2/kg-dry)$ in hulled seed were, depending on application time, $1.2{\times}10^3{\sim}5.0{{\times}10^3\;for\;^{54}Mn,\;1.6{\times}10^5{\sim}2.6{\times}10^4\;for\;^{60}Co,\;1.1{\times}10^4{\sim}7.6{\times}10^4\;for\;^{85}Sr\;and\;5.2{\times}10^5{\sim}7.0{\times}10^4\;for\;^{137}Cs$. The highest factors of all the radionuclides in straw came from the application at 67 days after transplanting while those of $^{54}Mn,\;^{60}Co\;and\;^{85}Sr$ in hulled seed appeared at later applications. The data from this studv can be referred to in assessing the radiological impact of an accidental contamination during the rice growth.

• The Korean Journal of Nuclear Medicine
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• v.7 no.2
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• pp.37-41
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• 1973

Bone scanning was attempted in the five representative cases in various diseases such as primary bone tumor, inflammatory or traumatic changes, secondary metastatic bone tumor and changes in the hematopoietic system with Sr-85 which is available at this time. Each findings were correlated to the X-ray findings. Scan findings were more appreciable than the X-ray findings in elucidation of extent of bone pathology in cases of primary bone tumor and fracture cases. Especially, increased radioactivity was noted on the clinically suspected region which were not demonstrated on the plain X-rays.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.639-644
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• 1998

온실내에서 $^{85}$ Sr, $^{103}$ Ru, $^{134}$ Cs의 혼합용액을 배추의 생육중 다섯 차례에 걸쳐 분무기를 이용하여 엽면 처리하고 오염경로를 해석하였다. 작물체에 의한 차단계수는 핵종간에 차이없이 처리시기가 수확기에 가까울수록 증가하여 최고 약 0.9에 달하였다. 작물체에 침적한 핵종의 수확시 잔류율은 처리시기에 따라 $^{85}$ Sr가 16~58%, $^{103}$ Ru이 15~73%, $^{134}$ Cs가 33～64%의 범위로 생육전기 처리 시에는 $^{134}$ Cs가, 후기 처리시에는 $^{103}$ Ru이 가장 높았다. 강우처리에 의해 수확시 핵종농도가 비교적 크게 감소됨을 확인하였다. 수확된 배추의 겉잎을 제거함으로써 배추내 핵종농도를 효과적으로 낮출 수 있다는 것이 입증되었다. 본 연구결과는 배추의 생육중 사고침적시 배추내 핵종농도 예측 및 대책 수립에 활용될 수 있다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04b
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• pp.88-91
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• 2000

The $(Sr_{0.85}Ca_{0.15})TiO_3$(SCT) thin films are deposited on Pt-coated electrode(Pt/TiN/$SiO_2$/Si) using RF sputtering method. The crystallinity of SCT thin films is increased with increase of substrate temperature in the temperature range of 200~500$[^{\circ}C]$. V-I characteristics of SCT thin films show the increasing leakage current with the increases of deposition temperature. The conduction mechanism of the SCT thin films observed in the temperature range of 25~100$[^{\circ}C]$ can be divided into four characteristic regions with different mechanism by the increasing current.

• Journal of the Korean Graphic Arts Communication Society
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• v.7 no.1
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• pp.49-59
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• 1989

This study was made to Investigate the effect of tensile strength(kg/cm$^{2}$), opacity(%), porosity(cc/min) of the paper manufacturing with the freeness properties of NBKP and the calcium carbonate having the different physical and chemical properties. As the results, the opacity and porosity of the freeness of, NBKP, obtained good strength properties from the freeness 65$^{\circ}$SR and the tensile strength from the freeness 85$^{\circ}$SR. The strength properties of paper manufacturing loaded with calcium carbonate appears to be related to the effect of the freeness, and it was obtained the good results at opacity 83.8% in the freeness 85$^{\circ}$SR, tensile strength 3.8kg/m$^{2}$ porosity 87cc/min in the freeness 65$^{\circ}$SR. Addition of 50%, 55%, 60% CaCO$_{3}$ was found to increase slightly the strength properties of paper.

• Journal of the Korean Graphic Arts Communication Society
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• v.7 no.1
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• pp.31-39
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• 1989

This study was made to investigate the effect of tensile strength(kg/$\textrm{cm}^2$), opacity (%), porosity(cc/min) of the paper manufaturing with the freeness properties of NBKP and the calcium carbonate having the different physical and chemical properties.As the results, the opacity and porosity of the freeness of NBKP, obtained good strength properties from the freeness 65$^{\circ}$SR and the tensile strength from the freeness 85$^{\circ}$SR. The strength properties of paper manufacturing loaded with calcium carbonate appears to be related to the effect of the freeness, and it was obtained the good results at opacity 83.8% in the freeness 85$^{\circ}$SR, tensile strength 3.8kg/$m^2$ porosity 87cc/min in the freeness 65$^{\circ}$SR.Addition of 50%, 55% 60%, CaCo3 was found to increase slightly the strength properties of paper.