15,588 research outputs found
Toward a test of angular momentum coherence in a twin-atom interferometer
We present a scheme well-suited to investigate quantitatively the angular
momentum coherence of molecular fragments. Assuming that the dissociated
molecule has a null total angular momentum, we investigate the propagation of
the corresponding atomic fragments in the apparatus. We show that the
envisioned interferometer enables one to distinguish unambiguously a
spin-coherent from a spin-incoherent dissociation, as well as to estimate the
purity of the angular momentum density matrix associated with the fragments.
This setup, which may be seen as an atomic analogue of a twin-photon
interferometer, can be used to investigate the suitability of molecule
dissociation processes -- such as the metastable hydrogen atoms H()-H() dissociation - for coherent twin-atom optics.Comment: 6 pages, 3 Figures. Final version accepted for publication in
Europhysics Letter
A mathematical framework for reducing the domain in the mechanical analysis of periodic structures
A theoretical framework is developped leading to a sound derivation of
Periodic Boundary Conditions (PBCs) for the analysis of domains smaller then
the Unit Cells (UCs), named reduced Unit Cells (rUCs), by exploiting
non-orthogonal translations and symmetries. A particular type of UCs,
Offset-reduced Unit Cells (OrUCs) are highlighted. These enable the reduction
of the analysis domain of the traditionally defined UCs without any loading
restriction. The relevance of the framework and its application to any periodic
structure is illustrated through two practical examples: 3D woven and
honeycomb.Comment: 18 page
Processing and characterization of extruded breakfast meal formulated with broken rice and bean flour.
O objetivo deste trabalho foi elaborar um produto matinal extrusado de quirera de arroz e bandinha de feijão, além de verificar a influência do processo de extrusão nas suas características físico-químicas, nutricionais, tecnológicas e sensoriais. O produto final apresentou teor considerável de proteínas (9,9 g.100 g–1), podendo ser considerado uma boa fonte desse nutriente para crianças e adolescentes. Para a fibra alimentar, observou-se teor de 3,71 g.100 g–1 do produto pronto para o consumo. Dessa forma, o floco matinal de arroz e feijão pode receber a alegação de alimento fonte de fibras, de acordo com a legislação brasileira. Com relação às propriedades tecnológicas, o extrusado estudado apresentou índice de expansão de 8,89 e densidade aparente de 0,25 g.cm-3. Quanto à análise sensorial, o floco matinal avaliado obteve notas médias de aceitação, situadas no intervalo de 6,8 a 7,7, que corresponde às categorias “gostei ligeiramente” e “gostei muito”. Para a intenção de compra, 79% dos provadores opinaram que certamente ou possivelmente comprariam o produto. O emprego de quirera de arroz e bandinha de feijão é uma interessante alternativa para a elaboração de produto matinal extrusado, apresentando boas qualidades de ordem nutricional, tecnológica e sensorial
Efeito da pasta bordalesa no controle da resinose do coqueiro causada por Thielaviopsis paradoxa.
Efeito da pasta bordalesa no controle da resinose do coqueiro causada por Thielaviopsis paradoxa.
Self-organized patterns of coexistence out of a predator-prey cellular automaton
We present a stochastic approach to modeling the dynamics of coexistence of
prey and predator populations. It is assumed that the space of coexistence is
explicitly subdivided in a grid of cells. Each cell can be occupied by only one
individual of each species or can be empty. The system evolves in time
according to a probabilistic cellular automaton composed by a set of local
rules which describe interactions between species individuals and mimic the
process of birth, death and predation. By performing computational simulations,
we found that, depending on the values of the parameters of the model, the
following states can be reached: a prey absorbing state and active states of
two types. In one of them both species coexist in a stationary regime with
population densities constant in time. The other kind of active state is
characterized by local coupled time oscillations of prey and predator
populations. We focus on the self-organized structures arising from
spatio-temporal dynamics of the coexistence. We identify distinct spatial
patterns of prey and predators and verify that they are intimally connected to
the time coexistence behavior of the species. The occurrence of a prey
percolating cluster on the spatial patterns of the active states is also
examined.Comment: 19 pages, 11 figure
Application of raw broken rice and extruded broken bean flours for formulation of gluten-free cake mixtures.
Efeito da pasta bordalesa no controle da resinose do coqueiro causada por Thielaviopsis paradoxa.
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