Envíos recientes

  • Study of optical fiber sensors for cryogenic temperature measurements 

    Miguel Soto, Verónica de; Leandro González, Daniel Upna; López Aldaba, Aitor Upna; Beato López, Juan Jesús; Pérez de Landazábal Berganzo, José Ignacio; Auguste, Jean-Louis; Jamier, Raphael; Roy, Philippe; López-Amo Sáinz, Manuel Upna (MDPI, 2017)   Artículo / Artikulua  OpenAccess
    In this work, the performance of five different fiber optic sensors at cryogenic temperatures has been analyzed. A photonic crystal fiber Fabry-Pérot interferometer, two Sagnac interferometers, a commercial fiber Bragg ...
  • Giant direct and inverse magnetocaloric effect linked to the same forward martensitic transformation 

    Pérez de Landazábal Berganzo, José Ignacio; Recarte Callado, Vicente Upna; Sánchez-Alarcos Gómez, Vicente Upna; Beato López, Juan Jesús; Rodríguez Velamazán, José Alberto; Sánchez Marcos, J.; Gómez Polo, Cristina; Cesari, Eduard (Springer Nature, 2017)   Artículo / Artikulua  OpenAccess
    Metamagnetic shape memory alloys have aroused considerable attraction as potential magnetic refrigerants due to the large inverse magnetocaloric effect associated to the magnetic-field-induction of a reverse martensitic ...
  • Loss of ductility due to the decarburation and Mn depletion of a coarse-grained TWIP steel 

    Cuevas Jiménez, Fernando de las; Gil Sevillano, J. (Consejo Superior de Investigaciones Científicas (CSIC), 2017)   Artículo / Artikulua  OpenAccess
    Se ha observado una clara transición de la ductilidad a tracción con el tamaño de grano D del orden 15 μm - 20 μm (1,50 μm ≤ D < 50 μm) en un acero TWIP, 22% de Mn, 0,6% de C (% en masa). Este comportamiento es una combinación ...
  • Entropy change caused by martensitic transformations of ferromagnetic shape memory alloys 

    L'vov, Victor A.; Cesari, Eduard; Kosogor, Anna; Torrens Serra, Joan; Recarte Callado, Vicente Upna; Pérez de Landazábal Berganzo, José Ignacio (MDPI, 2017)   Artículo / Artikulua  OpenAccess
    In this paper, our most recent findings on the influence of magnetic order on the main transformational caloric and elastic properties of shape memory alloys (SMAs) are reviewed. It is argued that ferromagnetic order has ...
  • Structurally oriented nano-sheets in Co thin films: changing their anisotropic physical properties by thermally-induced relaxation 

    Vergara Platero, José Upna; Favieres Ruiz, Cristina Upna; Magén, César; Teresa, José María de; Ibarra, Manuel Ricardo; Madurga Pérez, Vicente Upna (MDPI, 2017)   Artículo / Artikulua  OpenAccess
    We show how nanocrystalline Co films formed by separated oblique nano-sheets display anisotropy in their resistivity, magnetization process, surface nano-morphology and optical transmission. After performing a heat treatment ...
  • Low field magnetic and thermal hysteresis in antiferromagnetic dysprosium 

    Liubimova, Iuliia; Corró Moyá, Miguel; Torrens Serra, Joan; Recarte Callado, Vicente Upna; Pérez de Landazábal Berganzo, José Ignacio; Kustov, Sergey (MDPI, 2017)   Artículo / Artikulua  OpenAccess
    Magnetic and thermal hysteresis (difference in magnetic properties on cooling and heating) have been studied in polycrystalline Dy (dysprosium) between 80 and 250 K using measurements of the reversible Villari effect and ...
  • Long-range atomic order and entropy change at the martensitic transformation in a Ni-Mn-In-Co metamagnetic shape memory alloy 

    Sánchez-Alarcos Gómez, Vicente Upna; Recarte Callado, Vicente Upna; Pérez de Landazábal Berganzo, José Ignacio; Cesari, Eduard; Rodríguez Velamazán, José Alberto (MDPI, 2014)   Artículo / Artikulua  OpenAccess
    The influence of the atomic order on the martensitic transformation entropy change has been studied in a Ni-Mn-In-Co metamagnetic shape memory alloy through the evolution of the transformation temperatures under high-temperature ...
  • Strategic noise map of a major road carried out with two environmental prediction software packages 

    Arana Burgui, Miguel Upna; San Martín Murugarren, Ricardo Upna; San Martín Erviti, María Luisa Upna; Aramendía Santamaría, Emilio Upna (Springer Netherlands, 2010)   Artículo / Artikulua  OpenAccess
    The main objective of this study is to analyze the differences found in the results of noise mapping using two of the most popular software techniques for the prediction of environmental noise. The location selected ...
  • Are urban noise pollution levels decreasing? 

    Arana Burgui, Miguel Upna (Acoustical Society of America, 2010)   Artículo / Artikulua  OpenAccess
    The majority of acoustic impact studies developed over the last 50 years have used a similar acoustic parameter Leq, Ldn but the noise mapping methodology has been very uneven. The selection of the measurement points, ...
  • Simple fabrication of ultrahigh aspect ratio nanostructures for enhanced antireflectivity 

    Domínguez Fernández, Sagrario; Cornago Santos, Ignacio; Bravo Larrea, Javier Upna; Pérez Conde, Jesús Upna; Choi, Hyungryul J.; Kim, Jeong-Gil; Barbastathis, George (American Vacuum Society, 2014)   Artículo / Artikulua  OpenAccess
    In this work, the authors present a novel fabrication process to create periodic nanostructures with aspect ratio as high as 9.6. These nanostructures reduce spectral reflectance of silicon to less than 4% over the broad ...
  • Method for measurement of transition probabilities by laser-induced breakdown spectroscopy based on CSigma graphs. Application to Ca II spectral lines 

    Aguilera Andoaga, José Antonio Upna; Aragón Garbizu, Carlos Upna; Manrique Rosel, Javier (Elsevier, 2015)   Artículo / Artikulua  OpenAccess
    We propose a method for determination of transition probabilities by laser-induced breakdown spectroscopy that avoids the error due to self-absorption. The method relies on CSigma graphs, a generalization of curves of ...
  • CSigma graphs: a new approach for plasma characterization in laser-induced breakdown spectroscopy 

    Aragón Garbizu, Carlos Upna; Aguilera Andoaga, José Antonio Upna (Elsevier, 2014)   Artículo / Artikulua  OpenAccess
    A generalization of curves of growth called CSigma (Cσ) graphs, which allows including several lines of various elements in the same ionization state at different concentrations, is proposed for laser-induced breakdown ...
  • Magnetic anisotropy in isotropic and nanopatterned strongly exchange-coupled nanolayers 

    Vergara Platero, José Upna; Favieres Ruiz, Cristina Upna; Madurga Pérez, Vicente Upna (Springer, 2012)   Artículo / Artikulua  OpenAccess
    In this study, the fabrication of magnetic multilayers with a controlled value of the in-plane uniaxial magnetic anisotropy field in the range of 12 to 72 kA/m was achieved. This fabrication was accomplished by the ...
  • Generating and measuring the anisotropic elastic behaviour of Co thin films with oriented surface nano-strings on micro-cantilevers 

    Madurga Pérez, Vicente Upna; Vergara Platero, José Upna; Favieres Ruiz, Cristina Upna (Springer, 2011)   Artículo / Artikulua  OpenAccess
    In this research, the elastic behaviour of two Co thin films simultaneously deposited in an off-normal angle method was studied. Towards this end, two Si micro-cantilevers were simultaneously coated using pulsed laser ...
  • Aspectos biopsicológicos de la infección por virus inmunodeficiencia humana (VIH) 

    Aparicio Ágreda, María Lourdes Upna; Cuevas Jiménez, Carlos Pablo (Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006)   Artículo / Artikulua  OpenAccess
    El objetivo de este artículo es ofrecer una comprensión global de la infección por VIH. Si bien es un proceso inicialmente asintomático, el avance de la infección produce consecuencias a nivel de funcionamiento, en gran ...