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Article: Ba(OH)[.sub.2] equilibria in the system Ba-O-H-F, with application to the formation of [Ba.sub.2]Y[Cu.sub.3][O.sub.6.5 + x] from Ba[F.sub.2]-precursors.
- Article from:
- Journal of Research of the National Institute of Standards and Technology
- Article date:
- March 1, 2005
- Author:
CopyrightCOPYRIGHT 2005 National Institute of Standards and Technology. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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The ex situ process for fabricating [Ba.sub.2]Y[Cu.sub.3][O.sub.6.5 + x] superconducting tapes from Ba[F.sub.2]-based precursors involves a hydration/oxidation reaction at [approximately equal to]730[degrees]C to 750[degrees]C generally written as:
(2 BaF2 + Y + 3 Cu)(amorphous) + (2 [H.sub.2]O + 2.25 [O.sub.2])(g) [right arrow] [Ba.sub.2]Y[Cu.sub.3][O.sub.6.5 + x](s) + 4 HF(g).
However, microscopic observations of partially processed films suggest the presence of a transient liquid phase during conversion. Alternatively, the conversion reaction can be rewritten as the sum of several intermediate steps, including the formation of a barium hydroxide ...
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Article: Amino Acid Substitutions in the Pore of the Ca^sub v^1.2 ...
Biophysical Journal;
September 1, 2005 ;
700+ words
... ... with lysine, reduces whole-cell G^sub Ba^/G^sub Ca^ from 2.2 (wild ... measurements indicate that reductions in G^sub Ba^/G^sub Ca^ result specifically ... are not important for determining G^sub Ba^/G^sub Ca^, because the fold ...
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