• Title/Summary/Keyword: Y211

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$Y_BaCuO_5$ Distribution within $YBa_2Cu_3O_{7-x}$ Grains of Melt Infiltration Processed YBCO Oxides (융융체 침투법으로 제조한 YBCO 산화물에서 $YBa_2Cu_3O_{7-x}$ 결정립 내 $Y_BaCuO_5$ 입자분포)

  • 김찬중;이동만;지영아;박해웅;홍계원
    • Journal of Powder Materials
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    • v.7 no.4
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    • pp.205-211
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    • 2000
  • Distribution of $Y_2BaCuO_5$ (211) Particles within $YBa_2Cu_3O_{7-x}/$ (123) grains of melt infiltration processed YBCO oxides was investigated. Processing parameters were a temperature, atmosphere (air and $O_2$) and initial 211 size. The 211 particles were distributed randomly within the 123 grains when the initial 211 size was large, while they made x-like pattern and/or butterfly-like patterns when the 211 size was small. The 211 patterns were more clearly observed in the samples prepared at higher temperatures and under $O_2$ atmosphere. The 211 distribution was explained in terms of the interfacial energy relationship among the solid, particle and melt.

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Responses of Alkoxyresorufin Dealkylases and Glutathione S-transferase Activities of Surf Clam, Pseudocardium sachalinensis, Injected with Sea-Nine 211 Antifoulant (Tin-free 방오제인 Sea-Nine 211을 주사한 북방대합에서 alkoxyresorufin 탈알킬화효소와 글루타치온 포합효소 활성의 변화)

  • Lee, Ji-Seon;Jeon, Yeong-Ha;Shim, Won-Joon;Jeon, Joong-Kyun
    • Korean Journal of Environmental Biology
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    • v.26 no.2
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    • pp.109-114
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    • 2008
  • To evaluate the extent of Sea-Nine 211 (4,5-dichloro-2-n-octyl-3(2H) isothiazolone), one of the alternating organic booster compound used in antifouling paint to replace TBT, on marine benthic bivalve, we injected Sea-Nine 211 to clam, Pseudocardium sachalinensis, and then determined some xenobiotics metabolizing enzyme activities, especially EROD (ethoxyresorufin deethylase) and MROD (methoxyresorufin demethylase), in digestive gland during 4 day-exposure period. Moreover, the results were compared with those of TBT exposed clam. CYP1A1 dependant EROD activity in both the Sea-Nine 211 and the TBTC exposure groups showed no significant differences compared to those of the solvent control group. CYP1A2 dependant MROD activity in Sea-Nine 211 exposure group was significantly induced, but no significant difference was obtained in the TBTC exposure group. These results indicate that Sea-Nine 211 demonstrated a tendency to induce MROD activity, while TBTC inhibits the activities of this enzyme.

Method of simultaneous synthesize for Y123 and Y211 and fabrication of YBCO single crystal (Y123와 Y211분말의 동시 합성과 YBCO 초전도 단결정 제조)

  • 안재원;최희락;한영희;한상철;정년호;성태현
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2002.05a
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    • pp.224-233
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    • 2002
  • A common YBCO powder has been made from a mixture of Y123 and Y211 that heated at different temperatures, respectively. The synthesis temperature of Y211 is lower than Y123. If Y211 has been heated as a synthesis temperature of Y123, a particle size of it may be very coarse. It exist as one of main defects for superconductor. But We simultaneously synthesize a YBCO(its composition is (Y123+0.4Y211)+$lwt%CeO_2$) using polymeric complex method. In the YBCO, the Y123 is synthesized lower temperature than other methodes, and its crystal structure is orthorombic. For measurement of these superconducting properties, we fabricated a YBCO single crystal. The manufactured YBCO single crystal is measured a magnetic distribution device using 0.5Tesla magnet and trapped magnet fields in it are 0.2Tesla.

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Responses of MFO System in Surf Clam, Pseudocardium sachalinensis, Injected with Sea-Nine 211 Antifoulant (Tin-free 방오제인 Sea-Nine 211에 노출된 북방대합에서 MFO 효소계의 반응)

  • Lee, Ji-Seon;Jeon, Yeong-Ha;Shim, Won-Joon;Jeon, Joong-Kyun
    • Korean Journal of Environmental Biology
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    • v.26 no.2
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    • pp.102-108
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    • 2008
  • Many alternative biocidal additives were applied to antifouling paint to replace TBT, and Sea-Nine 211 is one of alternating organic booster compounds used in antifouling paint. In this study, extent of Sea-Nine 211 toxicity on marine benthic bivalve is evaluated. Sea-Nine 211 was injected to surf clam, Pseudocardium sachalinensis, that inhabitate northern part of Gangwon Province, Korea. Survival rate of the clam and xenobiotics metabolizing enzyme activities in digestive gland were measured during 4 day-exposure period. The results were compared with those of TBT exposed clam. There were no mortality of clam in the solvent (DMSO) control group and the three Sea-Nine 211 exposure groups (5, 25, 50 mg kg$^{-1}$ body weight), while the clam exposed to 1, 2 and 5 mg kg$^{-1}$ TBT chloride (TBTC) demonstrated 70, 30 and 0% survival rate, respectively. The Sea-Nine 211 exposure group showed a tendency of cytochrome P450 (CYP) induction according to the exposure duration, on the other hand, CYP content was decreased in the TBT exposure group. NADPH cytochrome P450 reductase activity slightly increase according to the exposure duration in the Sea-Nine 211 exposure group, while TBTC inhibit its activity as CYP content. Moreover, there was no significant change of NADH cytochrome b5 reductate activity in the clam epxosed to Sea-Nine 211. In the TBTC exposure group, its activity increased in early exposure period and then significantly decreased the rest of exposure period. All the results indicate that Sea-Nine 211 demonstrated a tendency to induce CYP level, while TBTC inhibits the CYP level, NADPH cytochrome P450 reductase and NADH cytochrome b5 reductase activities.

A Study on the Growth Behavior of $Y_2Ba_1Cu_1O_5$ Phase in Y-Ma-Cu-O System (Y-Ma-Cu-O계에서 $Y_2Ba_1Cu_1O_5$상의 성장거동에 관한연구)

  • Im, Dae-Ho;Song, Myeong-Yeop;Park, Jong-Hyeon;Lee, Hui-Gyun;Won, Dong-Yeon;Hong, Gye-Won
    • Korean Journal of Materials Research
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    • v.4 no.8
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    • pp.870-876
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    • 1994
  • In order to investigate the growth behavior of $Y_{2}Ba_{1}Cu_{1}O_{5}$(211) particles in $Y_{1}Ba_{2}Cu_{3}O_{7-\delta}$(123), 123 samples were quenched in air after heat treatment on polycrystal and single crystal MgO substrates at $1100^{\circ}C$ for various periods. 211 grains grew with the increase in holding time. The growth of 211 grains was faster on the polycrystal MgO substrate than on the single crystal MgO substrate. In the samples with the compositions of 211+xCuO($0.2\le X \le 0.8$), the growth rate of 211 grains increased with the increase in CuO content. In the sample with x=0.6 the largest 211 grains were observed. 211 grains in the $Y_{2}Ba_{1}Cu_{1.8}Sn_{0.1}O_{5+\delta}$ samples were distributed very finely and homogeneously. The retarding effect of $SnO_2$ addition on the growth of 211 grain appeared more pronounced in a CuO melt than in a $BaCuO_{2}$+ CuO melt.

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신제품

  • Korea Swine Association
    • The Korea Swine Journal
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    • v.19 no.8 s.216
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    • pp.211-211
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    • 1997
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Microstructural properties of Pt-doped $YBa_{2}Cu_{3}O_{7-x}$ high $T_c$ superconductor prepared by melting method.

  • Song, Jin-Tae
    • Proceedings of the Materials Research Society of Korea Conference
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    • 1992.05a
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    • pp.16-16
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    • 1992
  • We have studied the effect of platinum addition on the supercon ducting properties of YB $a_2$C $u_3$$O_{7-x}$ (123) compound and elucidated the mechanism of fine dispersion of $Y_2$BaCu $O_{5}$(211) particles in YB $a_2$C $u_3$$O_{7-x}$ superconductor prepared by melting method from the metallurgical point of view. In this study, BaCu $O_2$ and CuO-rich phase unreacted during the peritecitc reaction markedly decreased by the 211 powder addition. The 211 particle of Pt-fee sintered samples exhibited 8~10$\mu$m in size, but in 1wt%Pt-added sample, 211 particles were finely dispersed in 123 matrix and the size of 211 particle was about 1~2$\mu$m. And, the critical temperature( $T_{c. zero}$) of Pt doped samples was 91.5K and the transport critical current density ( $J_{c}$) of Pt-doped samples was much more than 10$^4$A/$\textrm{cm}^2$. The high $J_{c}$ and fine dispersion of 211 particles of Pt doped YB $a_2$C $u_3$$O_{7-x}$ superconductor are attributed to $Ba_4$CuP $t_2$ $O_{8}$ compounds formed during the partial melting, which were considered als nucleation sites of 211 particles, rather than Pt inself.han Pt inself.

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