3.1 Estancias en cooperación internacional

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https://hdl.handle.net/20.500.12390/3674

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  • Publicación
    Determination of the complex refractive index and optical bandgap of CH3NH3PbI3 thin films
    (AIP Publishing, 2017)
    Guerra, J. A.
    ;
    Tejada, A.
    ;
    Korte, L.
    ;
    Kegelmann, L.
    ;
    Tofflinger, J. A.
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    Albrecht, S.
    ;
    Rech, B.
    ;
    Weingartner, R.
    We report the complex refractive index of methylammonium lead iodide (CH3NH3PbI3) perovskite thin films obtained by means of variable angle spectroscopic ellipsometry and transmittance/reflectance spectrophotometry in the wavelength range of 190 nm to 2500 nm. The film thickness and roughness layer thickness are determined by minimizing a global unbiased estimator in the region where the spectrophotometry and ellipsometry spectra overlap. We then determine the optical bandgap and Urbach energy from the absorption coefficient, by means of a fundamental absorption model based on band fluctuations in direct semiconductors. This model merges both the Urbach tail and the absorption edge regions in a single equation. In this way, we increase the fitting region and extend the conventional (αℏω)2-plot method to obtain accurate bandgap values. © 2017 Author(s).
      9
  • Publicación
    Four new species of Aleiodes (Hymenoptera: Braconidae: Rogadinae) from the Neotropical Region
    (Cambridge University Press (CUP), 2017)
    Garro, Lidia Sulca
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    Shimbori, Eduardo Mitio
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    Penteado-Dias, Angelica Maria
    ;
    Shaw, Scott Richard
    Four new species of the Aleiodes apicalis (Brulle) species group (Hymenoptera: Braconidae: Rogadinae) from the Neotropical Region are described and illustrated: Aleiodes ambrosiae new species. from Peru, A. aquilesi new species from Costa Rica, and A. sachambrosiae new species and A. tapirape new species from Brazil. We also add new distribution records for Aleiodes molestus Cresson, from Costa Rica. With the addition of the new species, the A. apicalis species group has 11 species from the New World, six of which are recorded from Neotropical Region.
      8
  • Publicación
    Vacancy ordered γ-Fe 2 O 3 nanoparticles functionalized with nanohydroxyapatite: XRD, FTIR, TEM, XPS and Mössbauer studies
    (Elsevier, 2016)
    Ramos Guivar J.A.
    ;
    Sanches E.A.
    ;
    Bruns F.
    ;
    Sadrollahi E.
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    Morales M.A.
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    López E.O.
    ;
    Litterst F.J.
    Vacancy ordered maghemite (γ-Fe2O3) nanoparticles functionalized with nanohydroxyapatite (HAp – Ca10(PO4) 6(OH)2) have been successfully synthesized using an inexpensive co-precipitation chemical route. Evidence for the presence of vacancy order in maghemite was shown by the superstructure lines observed in X-ray diffraction. The adsorption of carboxyl groups of citric acid (C6H8O7) onto γ-Fe2O3 nanoparticles was investigated by FTIR, XPS and Mössbauer spectroscopy. From XPS surface analysis, two binding energies related to oxygen were attributed to bindings between C6H8O7/γ- Fe2O3 and C6H8O7/HAp from an interfacial reaction promoted by strongly adsorbed H2O molecules at the surface of these nanomaterials.
      8
  • Publicación
    Efecto de la adición de fluido folicular al medio de maduración de ovocitos para la producción In vitro de embriones de bovino (Bos taurus)
    (Universidad Nacional Jorge Basadre Grohmann, 2015)
    Limache Coaquera, Tito
    El presente trabajo de investigación se realizó en la ciudad de Lima, con el objetivo de evaluar el efecto de la adición del fluido folicular (FF) al medio de maduración de ovocitos sobre la producción in vitro de embriones bovinos.
      30
  • Publicación
    Evaluation of the leishmanicidal activity of plants used by Peruvian Chayahuita ethnic group
    (Elsevier B.V., 2007)
    Estevez Y.
    ;
    Castillo D.
    ;
    Pisango M.T.
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    Arevalo J.
    ;
    Rojas R.
    ;
    Alban J.
    ;
    Deharo E.
    ;
    Bourdy G.
    ;
    Sauvain M.
    Aim of the study: A total of 27 ethanolic plant extracts from 27 species were screened for leishmanicidal activity in vitro against Leishmania amazonensis. Most of the selected species (19) are traditionally used by the Chayahuitas, an Amazonian Peruvian ethnic group, to treat skin affections and/or leishmaniasis.
      17