1,554 research outputs found
Produção e caracterização de nanofibrilas de celulose de casca de pinhão e avaliação da toxicidade e de metabolismo em ratos.
Resumo. MIPE
Produção de etanol celulósico a partir de biomassa florestal com utilização de enzimas lignocelulolíticas.
Spin Glass and ferromagnetism in disordered Cerium compounds
The competition between spin glass, ferromagnetism and Kondo effect is
analysed here in a Kondo lattice model with an inter-site random coupling
between the localized magnetic moments given by a generalization of
the Mattis model which represents an interpolation between ferromagnetism and a
highly disordered spin glass. Functional integral techniques with Grassmann
fields have been used to obtain the partition function. The static
approximation and the replica symmetric ansatz have also been used. The
solution of the problem is presented as a phase diagram giving {\it
versus} where is the temperature, and are the
strengths of the intrasite Kondo and the intersite random couplings,
respectively. If is small, when temperature is decreased, there is a
second order transition from a paramagnetic to a spin glass phase. For lower
, a first order transition appears between the spin glass phase and a
region where there are Mattis states which are thermodynamically equivalent to
the ferromagnetism. For very low , the Mattis states become stable. On
the other hand, it is found as solution a Kondo state for large
values. These results can improve the theoretical description of the well known
experimental phase diagram of .Comment: 17 pages, 5 figures, accepted Phys. Rev.
Inovação tecnológica com base em nanofribrilas de celulose de casca de pinhão: produção, estudo in vivo e aplicação na área de alimentos.
Resumo. MIPE
Avaliação das características morfológicas do sistema radicular de linhagens recombinantes endogâmicas de sorgo em solução nutritiva sob estresse de fósforo.
Estudo de fontes de nitrogênio na atividade de xilanases por Lentinula edodes em biomassa florestal.
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