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SrxBa1-xNb2O6 (SBN) ceramics were synthesized from Sr0.45Ba0.55Nb2O6 (45SBN) to 75SBN according to x content, and the mineral phases of ceramics were identified by XRD. Some SBN single crystals were grown by Czochralski method. There was only one single phase in from 45SBN to 70SBN when synthesizing at 1350 °C, but 75SBN ceramics had SrNb2O6 as second phase. The single crystal growth of SBN was generally difficult because of including bubbles, being black or poly-crystalline. This is considered to be related the properties of SBN ceramics synthesis as well as SBN melt. 60SBN and 75SBN single crystals have been grown in φ 4 cm Pt crucible with Pt wires as seed. And the crystals have grown to c-axis direction, and had some facets, which were identified.

We study gauged five-dimensional supergravity on the interval [0, πR]. We find a set of boundary conditions with respect to which the theory is locally supersymmetric. For theories with detuned brane tensions (Λ 4 < 0), we show that these boundary conditions can be used to spontaneously break global supersymmetry. For the original, tuned Randall-Sundrum scenario (Λ 4 = 0), we prove that the locally supersymmetric boundary conditions are also globally supersymmetric. We lift the theory from [0, πR] to S 1 and R, with arbitrary twists for the fermions, and cast these results in the language of the Scherk-Schwarz mechanism.