• Journal of the Korean Magnetics Society
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• v.2 no.1
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• pp.1-7
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• 1992

Deuterium was injected into melt-spun ribbons of ${\alpha}-Fe_{90}Zr_{10}$ using the electrolytic hydrogenation method, and the magnetic properties of these ${\alpha}-D_{x}Fe_{90}Zr_{10}$ ribbons were studied. By comparing these results with those of ${\alpha}-H_{x}Fe_{91}Zr_{9}$, the effects of phonons to magnetic properties were investigated. The Curie temperature $T_{c}$, and the spontaneous magnetizations of the $D_{47}Fe_{90}Zr_{10}$ and the $Fe_{90}Zr_{10}$ were studied using the Mbssbauer spectroscopy. From these investigations, it was found that the Curie temperature of $D_{x}Fe_{90}Zr_{10}$ was 75K higher than that of $Fe_{90}Zr_{10}$. It was believed that this indicated the importance of local deformation to the amorphous magnetism. Also by comparing the spontaneous magnetizations of $D_{47}Fe_{90}Zr_{10}$ with those of $Fe_{90}Zr_{10}$ as a function of temperature, it was found that the deuterium injection reduced the fluctuation of exchange integral.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1073-1090
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• 2018

Since the domestic utility tunnels were built mainly in the development project of the new city, they are all in the form of cut-and-cover box tunnel. But, in the case of overseas construction of utility tunnels for existing urban areas, the bored tunnel types are mainly adopted. It is reasonable to install bored tunnels in a downtown area because it is difficult to block the roads or install bypass roads due to heavy traffic and civil complaints. In order to activate the utility tunnels in bored type, it is necessary to secure optimized cross-sectional design technology considering the optimal supplying capacity and mutual influencing factors (Thermal Interference, electrolytic corrosion, efficiency of the maintenance, etc.) of utilities (power cables, telecommunication cables, water pipes, etc.). The optimal cross-section design method for bored utility tunnels is ultimately to derive the optimal arrangement technique for the utilities. In order to develop the design methods, firstly, the cases of tunnel cross-section (Shield TBM, Conventional Tunneling) in overseas shall be investigated to analyze the characteristics of the installation of utilities in the section and installation of auxiliary facilities, It is necessary to sort out and analyze the criteria related to the inner cross-section design (arrangement) presented in the standards and guidelines.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.1
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• pp.21-32
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• 1994

$CaF_2$ crystals were grown with various growth rates by Bridgman method, and the electrical properties of these were studied to examine the changes of ionic conductivities with growth rates by AC Impedance Analyzer. As the growth rates were higher, $CaF_2$ crystals were grown to polycrystals from single crystal. And as grain boundaries and various defects were altered, the ionic conductivities were changed dramatically. $YF_3$ added to $CaF_2$ for disorderizing $CaF_2$ structure and improving the number of $F^-$ carriers and vacancies in $CaF_2$ crystals. Then $Ca_{1-x}Y_XF_{2+X}$ crystals were gained. And the ionic conductivities of $Ca_{1-x}Y_XF_{2+X}$ crystals were investigated with $YF_3$ addition. The ionic conductivities of $CaF_2$ and $Ca_{1-x}Y_XF_{2+X}$ crystals with temperatures were compared. In addition, the effects of clusterings and defects on the electrical properties of solid electrolytes were researched.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.1
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• pp.27-36
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• 2012

Metal chloride waste is generated as a main waste streams in a series of electrolytic processes of a pyrochemical process. Different from carbonate or nitrate salt, metal chloride is not decomposed into oxide and chlorine but it is just vaporized. Also, it has low compatibility with conventional silicate glasses. Our research group adapted the dechlorination approach for the immobilization of waste salt. In this study, the composition of SAP ($SiO_2-Al_2O_3-P_2O_5$) was adjusted to enhance the reactivity and to simplify the solidification process as a subsequent research. The addition of $Fe_2O_3$ into the basic SAP decreased the SAP/Salt ratio in weight from 3 for SAP 1071 to 2.25 for M-SAP( Fe=0.1). The experimental results indicated that the addition of $Fe_2O_3$ increased the reactivity of M-SAP with LiCl-KCl but the reactivity gradually decreased above Fe=0.1. Also, introducing $B_2O_3$ into M-SAP requires no glass binder for the consolidation of reaction products. U-SAP ($SiO_2-Al_2O_3-Fe_2O_3-P_2O_5-B_2O_3$) could effectively dechlorinate the LiCl-KCl waste and its reaction product could be consolidated as a monolithic form without a glass binder. The leaching test result indicated that U-SAP 1071 was more durable than other SAPs wasteform. By using U-SAP, 1 g of waste salt could generated 3~4 g of wasteform for final disposal. The final volume would be about 3~4 times lower than the glass-bonded sodalite. From these results, it could be concluded that the dechlorination approach using U-SAP would be one of prospective methods to manage the volatile waste salt.