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Stochastic approach to the smart quantum confinement model in porous silicon
(Surface Science 515 (2002) L509-L513, 2002)
A model that encompasses two approaches to explain the photoluminescence in p-type porous silicon is proposed. The model considers a stochastic distribution of nanocrystallite sizes within the porous matrix and explain the ...
Random Electric Field Instabilities of Relaxor Ferroelectrics
(2017-06-13)
Relaxor ferroelectrics are complex oxide materials which are rather unique to study the effects of compositional disorder on phase transitions. Here, we study the effects of quenched cubic random electric fields on the ...
Tsunamis and Tsunami Hazards in Central America
(2000-02)
A tsunami catalogue for Central America is compiled containing 49 tsunamis for the
period 1539–1996, thirty seven of them are in the Pacific and twelve in the Caribbean. At the Caribbean side, 5 events are related with ...
Structure factor of a relaxor ferroelectric
(2015-04-14)
We study a minimal model for a relaxor ferroelectric including dipolar interactions, and short-range harmonic and anharmonic forces for the critical modes as in the theory of pure ferroelectrics together with quenched ...
A thermodynamic cycle for the solar cell
(2017-01-06)
A solar cell is a heat engine, but textbook treatments are not wholly satisfactory from a thermodynamic standpoint, since they present solar cells as directly converting the energy of light into electricity, and the current ...
Irreversibility in an ideal fluid
(2014-10)
When a real fluid is expelled quickly from a tube, it forms a jet separated from the surrounding fluid by a thin, turbulent layer. On the other hand, when the same fluid is sucked into the tube, it comes in from all ...
Chandler wobble: Stochastic and deterministic dynamics
(2016-09-18)
We propose a model of the Earth’s torqueless precession, the “Chandler wobble,” as a self-oscillation driven by positive feedback between the wobble and the centrifugal deformation of the portion of the Earth’s mass contained ...
The mechanical career of Councillor Orffyreus, confidence man
(2013-05)
In the early 18th century, J. E. E. Bessler, known as Orffyreus, constructed several wheels that he claimed could keep turning forever, powered only by gravity. He never revealed the details of his invention, but he ...
Tsunamis and tsunami prepardness in Costa Rica, Central America
(2005-12)
Pacific and Atlantic sides of Costa Rica there are coastal segments characterised by a flat relief, which increases the vulnerability of the coastal communities. In addition to tsunamis originating in the Middle American ...
Electronic structure of silicon-based nanostructures
(2007-08-30)
We have developed a unifying tight-binding Hamiltonian that can account for the electronic properties of recently proposed Si-based nanostructures, namely, Si graphene-like sheets and Si nanotubes. We considered the sp3s∗ ...