• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.44-44
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• 2010

Conventional water treatment facilities like precipitation process need large-scale equipment and wide space to purify the wastewater of paper factory. In case of massive waste water, high gradient magnetic separation (HGMS) parts are more effective to purify it rapidly and to occupy relatively small space, since large voids at filter with HGMS are adopted. Cryo-cooled Nb-Ti superconducting magnet with room temperature bore in diameter of 100 mm and 600 mm in height was used for magnetic separator. Magnetic filters were designed by the analysis of magnetic field distribution at superconducting magnets.

• Progress in Superconductivity
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• v.7 no.1
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• pp.97-101
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• 2005

Bi-22l2 tubes for fault current limiter (FCL) were fabricated by centrifugal melting process. $SrSO_4$ ($10\;wt.\;\%$) was added to Bi-2212 powder to lower the melting point of Bi-22l2 and to improve the mechanical properties. The BSCCO powder was completely melted at $1300\;^{\circ}C$ using the RF furnace and then poured into rotating steel mold. The steel mold, preheated at $450\;{\circ}C{\sim}550^{\circ}C$ for 2 hour was rotated at $1020{\sim}2520\;RPM$. The solidified BSCCO tube was cooled down to room temperature in the furnace for 48 hours and separated from the mold between Bi-2212 and the mold. $ZrO_2$ solution was used to separate it easily from the mold and Ag tape was attached in the mold inner wall of the mold to analysis electrical property. Bi-22l2 tube was often cracked when the cooling rate was high. BSCCO tubes with $70{\Phi}{\times}100\;mm,\;50{\Phi}{\times}100\;mm$ and $30{\Phi}{\times}150\;mm$ size were fabricated by centrifugal melting process. The $J_{c}s$ of tubes with $50{\Phi}{\times}100\;mm{\times}4.0\;t$ and $50{\Phi}{\times}100\;mm{\times}4.l\;t$ were 178 and $74.2\;A/cm^2$ at 77K, respectively. The processing condition for Bi-2212 tube fabrication was investigated using XRD and SEM analyses.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.343-347
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• 1999

We fabricated a resistive SFCL having a shunt resistor parallel to it in order to bifurcate the transient current at faults. The SFCL consists of a YBCO film coated with an Au layer (10 ${\omega}$ at room temperature), which is to disperse the heat generated at hot spots in the YBCO film, and the 5 ${\omega}$ shunt resistor. The minimum quench current of the SFCL was found to be 12.2 A$_{peak}$. This SFCL successfully controlled the fault current below 23 A$_{peak}$ which is otherwise to increase up to 113 A$_{peak}$. Bifurcation of the current resulted in the temperature rise of the YBCO/Au film 3 times slower than without the shunt, protecting the SFCL at high currents.