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Mesophase structure and behaviour in bulk and restricted geometry of a dimeric compound exhibiting a nematic–nematic transition
(Royal Society of Chemistry, 2016-07-28)
We present structural studies of a dimeric compound composed of a central heptyl spacer linking two mesogens consisting of terphenyl units at which two adjacent fluoro groups are attached to each central ring. The terminal ...
Higher-Order Topological Insulators
(American Association for the Advancement of Science, 2018-06)
Three-dimensional topological (crystalline) insulators are materials with an insulating bulk but conducting surface states that are topologically protected by time-reversal (or spatial) symmetries. We extend the notion of ...
Caracterización microestructural y propiedades termomecánicas de las aleaciones con memoria de forma de Cu-AL-Ni, en el dominio hipoeutectoide
(2017-03-24)
Las aleaciones con memoria de forma (SMA) de base Cobre presentan la ventaja frente a las de base Titanio que pueden trabajar implementadas en sensores o actuadores a temperaturas superiores a 100ºC. El objetivo general ...
Understanding the kinetic limitations of NaFePO4 as cathode active material for Na-ion battery
(2019-02-26)
El desarrollo del uso de baterías de litio-ion (LIBs) para el almacenamiento de energía eléctrica ha sido inevitable en los últimos veinte años, impulsado por preocupaciones ambientales y nuevos comportamientos de los ...
Effect of Molecular Flexibility on the Nematic-to-Isotropic Phase Transition for Highly Biaxial Molecular Non-Symmetric Liquid Crystal Dimers
(MDPI, 2011-10)
In this work, a study of the nematic (N)-isotropic (I) phase transition has been made in a series of odd non-symmetric liquid crystal dimers, the alpha-(4-cyanobiphenyl-4'-yloxy)-omega-(1-pyrenimine-benzylidene-4'-oxy) ...
Detection of Atomic Scale Changes in the Free Volume Void Size of Three-Dimensional Colorectal Cancer Cell Culture Using Positron Annihilation Lifetime Spectroscopy
(Public Library of Science, 2014-01-02)
Positron annihilation lifetime spectroscopy (PALS) provides a direct measurement of the free volume void sizes in polymers and biological systems. This free volume is critical in explaining and understanding physical and ...
Defects structure characterization of NiMnGa alloys by PALS
(IOP Publishing, 2013)
We have studied the behaviour of defects in off-stoichiometric Ni-Mn-Ga ferromagnetic shape memory alloys by means of positron lifetime spectroscopy. The measurements presented in this work have been performed in six ternary ...
Dispersion of gamma-Alumina Nano-Sized Spherical Particles in a Calamitic Liquid Crystal. Study and Optimization of the Confinement Effects
(MDPI, 2014-03)
We report an experimental study on confined systems formed by butyloxybenzylidene octylaniline liquid crystal (4O.8) + gamma-alumina nanoparticles. The effects of the confinement in the thermal and dielectric properties ...
Two Glass Transitions Associated to Different Dynamic Disorders in the Nematic Glassy State of a Non-Symmetric Liquid Crystal Dimer Dopped with gamma-Alumina Nanoparticles
(MDPI, 2015-06)
In the present work, the nematic glassy state of the non-symmetric LC dimer -(4-cyanobiphenyl-4-yloxy)--(1-pyrenimine-benzylidene-4-oxy) undecane is studied by means of calorimetric and dielectric measurements. The most ...
Propiedades dieléctricas y térmicas de cristales líquidos: dímeros y bent-core
(2016-05-06)
Los cristales líquidos son materiales de gran interés tecnológico que combinan propiedades de los líquidos, fluidez, y de los sólidos cristalinos, anisotropía.En esta tesis se presenta un estudio detallado de cristales ...