Técnica de avaliação da habilidade combinatória para a seleção eficiente de genitores de híbridos de arroz.

O uso dessa técnica levará a uma maior eficiência dos programas de criação de variedades híbridas e diminuirá globalmente os custos da pesquisa, reduzindo drasticamente o número de combinações híbridas a serem avaliadas. Adicionalmente, o ganho genético para habilidade combinatória em cada população, R ou B, será elevado e constante, garantindo a sustentabilidade do programa

ELECTRONIC PROPERTIES AND APPEARENCE OF A MARTENSITIC TRANSFORMATION IN B2-TYPE COMPOUNDS (TiNiX WITH X = Fe, Ru, Os)

The electronic properties of pseudo-binary transition metal alloys of B2-type structure TiNiX ( X = Fe, Ru, Os) are studied. The electronic specific heat coefficient γ show systematically a peak, or a "plateau", at the concentration where a martensitic phase appears and corresponds to the boundary limit of the structural map

The effect of Ni and Pt substitution in CeRh<SUB>2</SUB>Si<SUB>2</SUB>

A small replacement of Rh by Ni or Pt (about 10%) results in the destruction of anomalous magnetism (TN=36 K) of CeRh2Si2, leading to a heavy fermion ground state. Further substitution of Ni for Rh stabilizes the strong mixed valent state

Specific-heat behavior across the heavy-fermion to mixed-valence transition in CeCu<SUB>2-x</SUB>Ni<SUB>x</SUB>Si<SUB>2</SUB> alloys

Partial replacement of Cu by Ni in CeCu<SUB>2</SUB>Si<SUB>2</SUB> decreases the linear coefficient of specific heat (&#947;) significantly. The observed ratio of the susceptibility (as T&#8594;0) to &#947; seems to increase with the addition of nickel. The results lend support to our earlier conclusion on the evolution of the heavy-fermion ground state from the strong mixed-valence state

EXPERIMENTAL STUDY OF THE SUPERCONDUCTING SPINEL SYSTEM Li1+xTi2-xO4

We present new experimental results about the spine1 system Li1-xTi2-xO4. Specific heat data and transport properties show the high quality of the samples prepared by new routes. If stoichiometric compound satisfies BCS theory the mechanism of superconductivity seems to be more complex when off-stoichiometric compounds are considered, due to the vicinity of a metal-insulator transition