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Positron annihilation spectroscopy techniques applied to the study of an HPGe detector.
(São Sebastião, 2012-09-02)
Doppler Broadening Spectroscopy of the large Ge crystal of an HPGe detector was
perforrned using positrons from pair production of 6.13 MeV ϒ-rays from the 19F(p,αϒ) 16O reaction. Two HPGe detectors facing opposite sides ...
Oxygen related defects and vacancy clusters identified in sputtering grown UOx thin films by positron annihilation techniques
(Elsevier, 2021-08)
We experimentally studied the formation of vacancy clusters and oxygen related defects in uranium oxide (UOx) thin films (<70 nm) changing the stoichiometry in the x = 2.2?3.5 range. Films were deposited on Si(0 0 1) by ...
Impurity migration and effects on vacancy formation enthalpy in polycrystalline depleted uranium
(Elsevier Science, 2015-11)
We have used Doppler-broadening of the positron-electron annihilation radiation technique and VASP calculations to verify the previously reported vacancy formation enthalpy Hvf in polycrystalline depleted uranium. ...
Electron paramagnetic resonance and positron annihilation study of the compensation mechanisms in donor-doped BaTiO3 ceramics
(Pergamon-Elsevier Science Ltd, 2007-07)
A study of the defect structure of BaTiO3-based ceramics and their correlation with the compensation mechanisms is presented. The addition of different Nb2 O5, Sb2 O3 or La2 O3 oxide contents (ranging from 0.05 to 0.60 ...
Decoration of Buried Surfaces in Si detected by Positron Annihilation Spectroscopy
(American Institute of Physics, 2006-12)
The terminations of buried surfaces of two different cavity types (nano- and microcavities) produced in the same He+-H+ co-implanted p-type Si (100) sample annealed at 900 °C, are studied and characterized by positron ...
Effect of the nano-cellulose content on the properties of reinforced polyurethanes. A study using mechanical tests and positron annihilation spectroscopy
(Elsevier, 2012-08-24)
A study of the effect of the addition of cellulose nanocrystals on the properties of a polyurethane matrix was carried out. To this aim, mechanical and dynamic mechanical tests together with positron annihilation lifetime ...
Vacancies and vacancy-oxygen complexes in silicon: Positron annihilation with core electrons
(The American Physical SocietyGrupo Estado SólidoEstados Unidos, 2017)
Mild degradation processes in ZnObased varistors: the role of Zn vacancies
(Taylor & Francis, 2015-02)
The effects of a degradation process on the structural and electrical properties of ZnO-based varistors induced by the application of dc bias voltage were analysed. Capacitance and resistance measurements were carried ...
Interstitial oxygen related defects and nanovoids in Au implanted a-SiO2 glass depth profiled by positron annihilation spectroscopy
(IOP Publishing, 2015-11)
Samples of amorphous silica were implanted with Au ions at an energy of 190 keV and fluences of 1×1014 ions cm−2and 5×1014 ions cm−2 at room temperature. The damage produced by ion implantation and its evolution with the ...