26,553 research outputs found
Hybrid Quasicrystals, Transport and Localization in Products of Minimal Sets
We consider convex combinations of finite-valued almost periodic sequences
(mainly substitution sequences) and put them as potentials of one-dimensional
tight-binding models. We prove that these sequences are almost periodic. We
call such combinations {\em hybrid quasicrystals} and these studies are related
to the minimality, under the shift on both coordinates, of the product space of
the respective (minimal) hulls. We observe a rich variety of behaviors on the
quantum dynamical transport ranging from localization to transport.Comment: 3 figures. To appear in Journal of Stat. Physic
Structure of trajectories of complex matrix eigenvalues in the Hermitian-non-Hermitian transition
The statistical properties of trajectories of eigenvalues of Gaussian complex
matrices whose Hermitian condition is progressively broken are investigated. It
is shown how the ordering on the real axis of the real eigenvalues is reflected
in the structure of the trajectories and also in the final distribution of the
eigenvalues in the complex plane.Comment: 12 pages, 3 figure
Hadronic form factors and the secondary production cross section: an update
Improving previous calculations, we compute the cross section using the most complete effective lagrangians available. The
new crucial ingredients are the form factors on the charm meson vertices, which
are determined from QCD sum rules calculations. Some of them became available
only very recently and the last one, needed for our present purpose, is
calculated in this work.Comment: 12 pages, 9 eps figure
Does the production asymmetry decrease at large ?
We have applied the meson cloud model (MCM) to calculate the asymmetries in
and meson production in high energy -nucleus and
-nucleus collisions. We find a good agreement with recent data. Our
results suggest that the asymmetries may decrease at large .Comment: revised version with new figures and added references to appear in
Phys. Rev. Let
Influência da adubação nitrogenada e potássica na podridão de colmo do milho por antracnose (Colletotrichum graminicola) em duas cultivares de milho
Trabalho apresentado no 42º Congresso Brasileiro de Fitopatologia, 2009, Rio de Janeiro, RJ
Importância da adubação nitrogenada e potássica na incidência de colmos podres por antracnose (Colletotrichum graminicola) e a sua relação com o peso de grãos em duas cultivares de milho.
Trabalho apresentado no 42º Congresso Brasileiro de Fitopatologia, 2009, Rio de Janeiro, RJ
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