Now showing items 1-14 of 14

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      Ab initio calculation of low-energy collective charge-density excitations in MgB2 

      Silkin, Viatcheslav M.; Balassis, A.; Echenique Landiribar, Pedro Miguel; Tchoulkov Savkin, Evgueni Vladimirovich (American Physical Society, 2009-08)
      We present ab initio time-dependent density-functional theory calculation results for low-energy collective electron excitations in MgB2. The existence of a long-lived collective excitation corresponding to coherent charge ...
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      Adaptive coatings based on polyaniline for direct 2D observation of diffusion processes in microfluidic systems 

      Florea, Larisa; Martin Mayor, Alain; Bou-Ali, M. Mounir; Meagher, Kate; Diamond, Dermot; Tutar, Mustafa; Benito López, Fernando ORCID (Elsevier, 2016-08)
      [EN] Therefore the understanding and proper evaluation of the flow and mixing behaviour at microscale becomes a very important issue. In this study, the diffusion behaviour of two reacting solutions of HCI and NaOH were ...
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      Energy loss of charged particles moving parallel to a magnesium surface 

      García Vergniory, Maia; Silkin, Viatcheslav M.; García de Gurtubay Galligo, Idoia ORCID; Pitarke de la Torre, José María ORCID (American Physical Society, 2008-10)
      We present it ab initio calculations of the electronic energy loss of charged particles moving outside a magnesium surface, from a realistic description of the one-electron band structure and a full treatment of the dynamical ...
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      Exact-exchange Kohn-Sham potential, surface energy, and work function of jellium slabs 

      Horowitz, Claudio M.; Proetto, C. R.; Pitarke de la Torre, José María ORCID (American Physical Society, 2008-08)
      Exact-exchange self-consistent calculations of the Kohn-Sham potential, surface energy, and work function of jellium slabs are reported in the framework of the optimized effective potential (OEP) scheme of density functional ...
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      Exchange-Correlation Hole of a Generalized Gradient Approximation for Solids and Surfaces 

      Constantin, Lucian A.; Perdew, John P.; Pitarke de la Torre, José María ORCID (American Physical Society, 2009-02)
      We propose a generalized gradient approximation (GGA) for the angle- and system-averaged exchange-correlation hole of a many-electron system. This hole, which satisfies known exact constraints, recovers the Perdew-Burke-Ernzerhof ...
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      First-principles calculations of hot-electron lifetimes in metals 

      Campillo Santos, Igor; Silkin, Viatcheslav M.; Pitarke de la Torre, José María ORCID; Tchoulkov Savkin, Evgueni Vladimirovich; Rubio Secades, Angel; Echenique Landiribar, Pedro Miguel (American Physical Society, 2000)
      First-principles calculations' of the inelastic lifetime of low-energy electrons in Al, Mg, Be, and Cu are reported. Quasiparticle damping rates are evaluated from the: knowledge of the electron self-energy, which we compute ...
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      Fluidic flow delay by ionogel passive pumps in microfluidic paper-based analytical devices 

      Akyazi, Tugce; Sáez Castaño, Janire; Elizalde, Jorge; Benito López, Fernando ORCID (Elsevier, 2016-10-05)
      [EN] A new concept for fluid flow manipulation in microfluidic paper-based analytical devices (m-PADs) is presented by introducing ionogel materials as passive pumps. m-PADs were fabricated using a new doubleside contact ...
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      Low‑cost origami fabrication of 3D self‑aligned hybrid microfluidic structures 

      Sáez Castaño, Janire; Basabe Desmonts, Lourdes ORCID; Benito López, Fernando ORCID (Springer, 2016-08)
      [EN] 3D microfluidic device fabrication methods are normally quite expensive and tedious. In this paper, we present an easy and cheap alternative wherein thin cyclic olefin polymer (COP) sheets and pressure sensitive ...
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      Microcantilever arrays functionalised with spiropyran photoactive moieties as systems to measure photo-induced surface stress changes 

      Grogan, Catherine; Florea, Larisa; Koprivica, Slavica; Scarmagnani, Silvia; O’Neill, Luke; Lyng, Fiona; Pedreschi, Fran; Benito López, Fernando ORCID; Raiteri, Roberto (Elsevier, 2016-12)
      [EN] Herein we investigate the feasibility of detecting photo-induced surface stress changes using the deflection response of cantilevers. For this purpose, silicon microcantilevers have been functionalised with spiropyran ...
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      Mild Hydrothermal Synthesis, Crystal Structure, Thermal Behavior, Spectroscopic and Magnetic Properties of (NH4)0.80Li0.20[Fe(AsO4)F] 

      Berrocal Torres, Teresa; Mesa Rueda, José Luis; Serrano Larrea, Edurne; Bazán Blau, Begoña del Pilar ORCID; Pizarro Sanz, José Luis ORCID; Lezama Diago, Luis María ORCID; Rojo Aparicio, Teófilo ORCID; Arriortua Marcaida, María Isabel ORCID (Elsevier, 2011-08-03)
      The (NH4)0.80Li0.20[Fe(AsO4)F] compound has been synthesized under mild hydrothermal conditions. The compound crystallize in the orthorhombic Pna21 space group, with cell parameters a= 13.352(9), b= 6.7049(9), c= 10.943(2) ...
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      On-demand generation and removal of alginate biocompatible microvalves for flow control in microfluidics 

      Sáez Castaño, Janire; Etxebarria Elezgarai, Jaione ORCID; Antoñana Díez, Marta; Benito López, Fernando ORCID (Elsevier, 2016-10-29)
      [EN] This paper describes, for the first time, the use of alginate hydrogels as miniaturised microvalves within microfluidic devices. These biocompatible and biodegradable microvalves are generated in situ and on demand, ...
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      Position-dependent exact-exchange energy for slabs and semi-infinite jellium 

      Horowitz, Claudio M.; Constantin, Lucian A.; Proetto, C. R.; Pitarke de la Torre, José María ORCID (American Physical Society, 2009-12)
      The position-dependent exact-exchange energy per particle epsilon(x)(z) (defined as the interaction between a given electron at z and its exact-exchange hole) at metal surfaces is investigated, by using either jellium slabs ...
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      Role of occupied d bands in the dynamics of excited electrons and holes in Ag 

      García Lekue, Aran; Pitarke de la Torre, José María ORCID; Tchoulkov Savkin, Evgueni Vladimirovich; Liebsch, A.; Echenique Landiribar, Pedro Miguel (American Physical Society, 2003)
      The role that occupied d bands play in the inelastic lifetime of bulk and surface states in Ag is investigated from the knowledge of the quasiparticle self-energy. In the case of bulk electrons, sp bands are taken to be ...
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      Upconversion cooling of Er-doped low-phonon fluorescent solids 

      García Adeva, Angel Javier ORCID; Balda de la Cruz, Rolindes ORCID; Fernández Rodríguez, Joaquín Manuel (American Physical Society, 2009-01)
      We report on a novel mechanism for laser cooling of fluorescent solids based on infrared-to-visible upconversion often found in rare-earth-doped low-phonon materials. This type of optical cooling presents some advantages ...