Now showing items 1-20 of 114

    Study of thermal transitions in polymers by a multifrequency modulated DSC technique 

    Fraga Rivas, Iria (Date of defense: 2010-02-26)

    Differential Scanning Calorimetry (DSC) is one of the most widely used thermal analysis techniques for the study of transitions and relaxation processes in polymers and also in other materials. It measures the heat flow ...

    Nonlinear frequency conversion under general phase mismatched condition: the role of phase locking and random nonlinear domains 

    Vito, Roppo (Date of defense: 2011-06-15)

    In the field of second harmonic (SH) generation most studies have been concerned with maximizing conversion efficiencies, generally achievable at the phase matching (PM) condition. Outside of the PM the conversion efficiency ...

    Dynamics in orientationally disordered solids 

    Martínez García, Julio César (Date of defense: 2011-07-15)

    The key features of dynamics of ultraslowing glass forming systems are their universality in diversity. Its origin is recognized as one of the greatest challenges of condensed matter physics and materials engineering in ...

    Bubble and droplet flow phenomena at different gravity levels 

    Suñol Galofré, Francesc (Date of defense: 2011-07-19)

    Two-phase flows are encountered in a wide range of applications both on-ground and in space. The dynamics of such flows in the absence of gravity is completely different from that in normal gravity due to the absence of ...

    Multi-dimensional simulations of mixing in classical novae 

    Casanova Bustamante, Jordi (Date of defense: 2011-11-03)

    Classical nova explosions are stellar explosions that take place in close binary systems with an energy release only exceeded by gamma-ray bursts and supernova explosions. Matter from the white dwarf flows through the inner ...

    Path Integral Monte Carlo and Bose-Einstein condensation in quantum fluids and solids 

    Rota, Riccardo (Date of defense: 2011-12-20)

    Several microscopic theories point out that Bose-Einstein condensation (BEC), i.e., a macroscopic occupation of the lowest energy single particle state in many-boson systems, may appear also in quantum fluids and solids ...

    Modelling the dynamics of large scale shoreline sand waves 

    Van Der Berg, Niels (Date of defense: 2012-05-11)

    Shoreline sand waves are shoreline undulations with a length scale of several kilometres and a time scale of years to decades. They occur on many coasts, migrating in the direction of the dominant littoral drift and they ...

    Hawking radiation in NS5 and little string theory 

    Lorente Espín, Oscar (Date of defense: 2012-09-20)

    In this thesis we have focused on semi-classical methods that enables us to obtain non-thermal spectra for the vast majority of black holes. This fact is due to taking into account the backreaction of the metric, when the ...

    Monte Carlo study of quantum phase transitions at zero temperature 

    Osychenko, Oleg N. (Date of defense: 2012-12-20)

    The Thesis is devoted to simulations of quantum phase transitions by means of Quantum Monte Carlo techniques. Quantum phase transition is a transition between phases at zero or low enough temperature, where quantum effects ...

    Dinámica de circuitos de regulación genética en bacterias 

    Espinar Calvo, María Lorena (Date of defense: 2012-12-21)

    El objetivo de esta Tesis es el estudio de diferentes comportamientos celulares dinámicos en Escherichia coli y Bacillus subtilis. Es interesante comprender cómo estos organismos sencillos poseen mecanismos complejos para ...

    Análisis estadístico y comportamiento fractal de las réplicas sísmicas del Sur de California 

    Monterrubio Velasco, Marisol (Date of defense: 2013-03-15)

    Mediante el análisis estadístico y utilizando diversas técnicas fractales en esta tesis se estudia el comportamiento temporal y espacial de tres series de réplicas sísmicas ocurridas en el Sur de California, que tuvieron ...

    Characterization of the structure, stability, mechanical and electrochemical properties of metallic glasses 

    Duarte Correa, María Jazmín (Date of defense: 2013-05-31)

    Metallic glasses are often referred as glassy or amorphous alloys. They lack long-range order and microstructural defects that are characteristics in crystals, such as grain and phase boundaries and dislocations. These new ...

    Non-linear fluid dynamics in oscillatory cylindrical cavities 

    Panadès i Guinart, Carles (Date of defense: 2013-06-28)

    Even though the transition to turbulence has been studied for over a century, its complete comprehension still remains unclear even for the simplest flows and continues to be a daunting challenge for the scientific community. ...

    Neuronal oscillations: from single-unit activity to emergent dynamics and back 

    Sancristóbal Alonso, Belén de (Date of defense: 2013-07-22)

    L’objectiu principal d’aquesta tesi és avançar en la comprensió del processament d’informació en xarxes neuronals en presència d’oscil lacions subumbrals. La majoria de neurones propaguen la seva activitat elèctrica a ...

    Transient and stochastic dynamics in cellular processes 

    Rué Queralt, Pau (Date of defense: 2013-07-25)

    This Thesis studies different cellular and cell population processes driven by non-linear and stochastic dynamics. The problems addressed here gravitate around the concepts of transient dynamics and relaxation from a ...

    Colour and technology in historic decorated glazes and glasses 

    Molina Giralt, Glòria (Date of defense: 2014-05-09)

    Historical decorated glass and glazed ceramics are studied with the object to determine the technology of production and to relate it with the optical properties (colour, shine, opacity). Four different case of study are ...

    Experimental study of feedback-induced dynamics in semiconductor lasers : from symbolic analysis to subwavelength position sensing 

    Aragoneses Aguado, Andrés (Date of defense: 2014-06-18)

    The aim of this thesis is the study of the dynamics induced by optical feedback in semiconductor lasers. This study aims, on the one hand, to improve our knowledge of stocahstic complex systems, and on the other hand, to ...

    Shaping of light beams with photonic crystals : spatial filtering, beam collimation and focusing 

    Maigyte, Lina (Date of defense: 2014-07-01)

    The research developed in the framework of this PhD thesis is a theoretical, numerical and experimental study of light beam shaping (spatial filtering, beam collimation and focusing) in the visible frequency range using ...

    Structural and electrical characterization of doped graphene and carbon nanotube networks 

    Iqbal, Muhammad Zahir (Date of defense: 2014-07-16)

    Graphene, a two-dimensional sp2-hybridized network of carbon atoms has received a remarkable cornucopia of new physics and served as a unique model system, due particularly to its electronic properties, which could have ...

    Short-range order in disordered phases using neutron diffraction 

    Rovira Esteva, Muriel (Date of defense: 2014-09-26)

    Neutron diffraction is a powerful technique that allows to probe the structure of disordered phases across a variety of length scales. However, due to the inherent complexity of these disordered hases, the analysis of the ...