Roberto P Borges

  • Citations Per Year
Learn More
The susceptibility of ~Sm0.65Sr0.35!MnO3 shows an unusual temperature dependence above the Curie temperature which is attributed to the presence of small manganese-ion clusters with S'9. A field-induced transition is observed in the paramagnetic state, which corresponds to a doubling of the cluster size and an increase of the strength of the interaction(More)
In this work argon and nitrogen were implanted into ZnO single crystals in order to compare the influence of these non-magnetic elements in the magnetic and electrical behaviour of zinc oxide. The results indicate that both nitrogen and argon implantations induce magnetic defects in ZnO, although these do not remain stable upon annealing. The comparison(More)
The mangrove crab Ucides cordatus is one of the most exploited crustaceans in Brazil. The present study investigated the breeding season of this species and the period of the "andada" phenomenon, when the crabs are active outside their burrows and perform agonistic behaviors. Furthermore related them to environmental factors, in a mangrove on the coast of(More)
  • 1