The high pressure synthesis and characterization of some rare-earth based praseodymium-substitute R2Ba4Cu7O14+δ (R = Sm, Gd, Ho) caprates
學年 86
學期 1
出版（發表）日期 1997-08-01
作品名稱 The high pressure synthesis and characterization of some rare-earth based praseodymium-substitute R2Ba4Cu7O14+δ (R = Sm, Gd, Ho) caprates
作品名稱（其他語言）
著者 Lai, Yu-Liang.; Chen, Teng-Ming; Shih, J. T.; Kao, H.-C. I.
單位 淡江大學化學學系
出版者 Amsterdam: Elsevier BV * North-Holland
著錄名稱、卷期、頁數 Physica C: Superconductivity and its Applications 281(2-3), pp.198-204
摘要 The stability of phases in the (R1 − xPrx)2Ba4Cu7O14 + δ (R = Sm, Gd, Ho; Pr-doped R247) systems with x = 0 to 1.0 and with an increment of 0.1 in x was investigated. Samples of the title Pr-doped R247 phases were prepared at 980–990°C under 20–36 bar of oxygen atmosphere, followed by long-time annealing at 300–320°C under 110–115 bar of oxygen. Single-phased samples were obtained with substitution limit (x) equal to 0.5, 0.6 and 0.7 for phases of the title (R1 − xPrx)2Ba4Cu7O14 + δ series with R = Sm, Dg, and Ho, respectively, as indicated by X-ray increasing Pr cement (x) both the lattie parameters and unit-cell volume were found to increase monotonically and, however, the corresponding crystallographic orthorhombicity, 2(b − a)/(b + a), was found to decrease with increasing x for all three Pr-doped series. The Tc of the Pr-doped R247 phases where found to suppressed from 69, 70 and 92 K down to 20 K (x = 0.4), 18 K (x = 0.5) and 8 K (x = 0.7) for Pr-doped R247 phases with R = Rm, Gd, and Ho, respectively. The composition coefficients of Tc, dTc/dx ,were found to be −50.4, −48.5, and −55.5 K./Pr-atom per formula unit for the title Pr-doped R247 series with R = Sm, Gd, Ho, respectively. The crystal structure, temperature-dependent resistivity and magnetization data of the Pr-doped R247 phases synthesized in our study are described and their implications are discussed.
關鍵字
語言 en
ISSN 0921-4534
期刊性質 國外
收錄於 SCI
產學合作
通訊作者
審稿制度
國別 NLD
公開徵稿
出版型式 紙本
相關連結

機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/25360 )

機構典藏連結