On torsion subgroups of whitehead groups of division algebras

We completely determine all torsion abelian groups that can occur as the torsion subgroup of the Whitehead group of a division algebra of prime index. More precisely, we prove that if D is a division algebra of prime index, then the torsion subgroup of K ₁(D) is locally cyclic. Conversely, if A is a torsion locally cyclic group, then there exists a division algebra D of prime index such that the torsion subgroup of K ₁(D) is isomorphic to A. Our result can be considered as a non-commutative version of May’s Theorem.     

Ni catalysts supported on nano-crystalline aluminum oxide prepared by a microemulsion method for dry reforming reaction

Mesoporous nano-crystalline γ-Al₂O₃ with high surface area prepared by a microemulsion (ME) method was employed as carrier for nickel catalysts in dry reforming of methane for syngas production. The structural properties of the catalysts were characterized by X-ray diffraction, Brunauer–Emmett–Teller surface area analysis, temperature programmed reduction and oxidation and scanning electron microscopy techniques. Microemulsion showed it to be a promising way for the production of nano-crystalline aluminum oxide, and the nickel catalysts prepared with this support have significant features and properties to use in the dry reforming reaction. The results revealed that the prepared γ-Al₂O₃ exhibited a nano-crystalline structure (crystal size: c.4.8 nm) with a high specific surface area (308 m² g^?1). In addition, the catalysts with different nickel contents exhibited high catalytic activity in the dry reforming reaction. The results also showed that an increase in Ni loading from 5 to 15 wt% caused a decrease in the specific surface area and nickel dispersion.