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An aqueous tape casting of Ce 0:8 Y 0:2 O 1:9 (YDC) ceramics was developed using poly(acrylic acid) (PAA) as a dispersant, poly(vinyl alcohol) (PVA) as a binder, poly(ethylene glycol) (PEG) as a plasticizer, and deionized water as a solvent. The surface properties of YDC powder with and without PAA dispersant were characterized by zeta potential. The rheological of the YDC slurries was evaluated with a rotary viscometer. The zeta potential measurement showed that the isoelectric point for YDC powders in the absence of dispersant had a pH value of 3.35. The experiment results showed that the pH value greatly affects the rheology of the slurry. In the presence of 2 wt % PAA dispersant, 55 wt % YDC powders exhibited shear thinning behavior, indicating that YDC slurry was homogenous and well stabilized. With an appropriate formulate, homogeneous, smooth, and defect-free green tapes were successfully obtained. Moreover, the crystallization kinetics of YDC powders prepared by the coprecipitation process has also been investigated in this study. The activation energy of crystallization was calculated on the basis of differential scanning calorimetry (DSC) at different heating rates. The activation energy of crystallization presented a value of 192.8 kJ/mol.

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A 6-dimensional grand unified theory with the compact space having the topology of a real projective plane, i.e., a 2-sphere with opposite points identified, is considered. The space is locally flat except for two conical singularities where the curvature is concentrated. One supersymmetry is preserved in the effective 4d theory. The unified gauge symmetry, for example SU(5) , is broken only by the non-trivial global topology. In contrast to the Hosotani mechanism, no adjoint Wilson-line modulus associated with this breaking appears. Since, locally, SU(5) remains a good symmetry everywhere, no UV-sensitive threshold corrections arise and SU(5)-violating local operators are forbidden. Doublettriplet splitting can be addressed in the context of a 6d N = 2 super Yang-Mills theory with gauge group SU(6). If this symmetry is first broken to SU(5) at a fixed point and then further reduced to the standard model group in the above non-local way, the two light Higgs doublets of the MSSM are predicted by the group-theoretical and geometrical structure of the model.

The nonisothermal crystallization kinetic of BixY3−xFe5O12 (0.25≤x≤1.00) powders prepared by coprecipitation process has been investigated. The activation energy of crystallization was calculated by differential scanning calorimetry at different heating rates. The activation energies of crystallization of BixY3−xFe5O12 system are 492, 447, 377, and 353 kJ/mol and the Avrami constant n are 3.49, 2.25, 2.48, and 2.33 for x=0.25, 0.50, 0.75, and 1.00, respectively. The Avrami exponent values (13) for the Avrami exponent was consistent with bulk crystallization domination in BixY3−xFe5O12 system. The results reveal that increasing the substitution amount of bismuth for yttrium would significantly decrease activation energy in BixY3−xFe5O12 system.