5,957 research outputs found
Estudo sensorial da qualidade de azeites de oliva virgem extra monovarietais e blend`s comercializado no Rio Grande do Sul.
Bilayer graphene under pressure: Electron-hole Symmetry Breaking, Valley Hall Effect, and Landau Levels
The electronic structure of bilayer graphene under pressure develops very
interesting features with an enhancement of the trigonal warping and a
splitting of the parabolic touching bands at the K point of the reciprocal
space into four Dirac cones, one at K and three along the T symmetry lines. As
pressure is increased, these cones separate in reciprocal space and in energy,
breaking the electron-hole symmetry. Due to their energy separation, their
opposite Berry curvature can be observed in valley Hall effect experiments and
in the structure of the Landau levels. Based on the electronic structure
obtained by Density Functional Theory, we develop a low energy Hamiltonian that
describes the effects of pressure on measurable quantities such as the Hall
conductivity and the Landau levels of the system.Comment: 11 pages, 9 figure
Effects of quark family nonuniversality in SU(3)_c X SU(4)_L X U(1)_x models
Flavour changing neutral currents arise in the extension of the standard model because anomaly cancellation among the
fermion families requires one generation of quarks to transform differently
from the other two under the gauge group. In the weak basis the distinction
between quark families is meaningless. However, in the mass eigenstates basis,
the Cabibbo-Kobayashi-Maskawa mixing matrix motivates us to classify
left-handed quarks in families. In this sense there are, in principle, three
different assignments of quark weak eigenstates into mass eigenstates. In this
work, by using measurements at the Z-pole, atomic parity violation data and
experimental input from neutral meson mixing, we examine two different models
without exotic electric charges based on the 3-4-1 symmetry, and address the
effects of quark family nonuniversality on the bounds on the mixing angle
between two of the neutral currents present in the models and on the mass
scales and of the new neutral gauge bosons predicted by the
theory. The heaviest family of quarks must transform differently in order to
keep lower bounds on and as low as possible without
violating experimental constraints.Comment: 27 pages, 10 tables, 2 figures. Equation (19) and typos corrected.
Matches version to appear in Phys. Rev.
Parâmetros físico-químicos de azeites virgem extra "gourmet" varietais comercializados no mercado do Rio Grande do Sul.
Metodologia para utilização de aeromodelos em monitoramento aéreo.
O projeto ARARA (Aeronaves de Reconhecimento assistidas por Rádio e Autônomas), está centrado no desenvolvimento e uso de UAV's, de escala reduzida, para monitoramento aéreo. Seu principal objetivo é a substituição de aeronaves convencionais utilizadas na obtenção de fotografias aéreas, para monitoramento de áreas agrícolas e áreas sujeitas a problemas ambientais, por UAV's de pequeno porte que realizam missões pré-estabelecidas pelos usuários.bitstream/CNPDIA/8116/1/CiT15_2002.pd
Monitoramento Agrícola a Partir de Imagens Aéreas e WebMapping .
bitstream/CNPDIA/10446/1/BPD08_2004.pd
Double beta decay of : the deformed limit
The double beta decay of to the ground state and excited states of
is analysed in the context of the pseudo SU(3) scheme. The results
of this deformed limit are compared with the vibrational one based on the QRPA
formalism. Consistency between the deformed limit and the experimental
information is found for various transitions, although, in this
approximation some energies and B(E2) intensities cannot reproduced.Comment: 16 pages, revtex, no figures. Submmitted to Phys. Rev.
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