16 research outputs found

    "Invisible burials" and fragmentation practices in Iron Age Europe:Excavations at the Monte Bernorio Necropolis (Northern Spain)

    Get PDF
    The scarcity of burial remains in large parts of Iron Age Europe, particularly in the Atlantic regions, has often led scholars to discuss the apparent “invisibility” of graves. This paper presents the results from several excavation campaigns at Monte Bernorio, one of the most important sites of the 1st millennium b.c. on the Iberian Peninsula. The fieldwork and post-excavation work carried out in the area of the necropolis have identified numerous burial pits, with complex ritual activities characterized by fragmentation and the practice of the pars pro toto. In addition, evidence for later rituals in some of the graves can be linked to ancestor worship. The results provide important insights into funerary practices in Late Iron Age Europe, leading us to rethink the very meaning of cemeteries in the study area and beyond.- Burial Traditions in Iron Age Europe - The Monte Bernorio Archaeological Zone - The 2007–2008 Necropolis Excavations - The 2015–2016 Necropolis Excavations - Post-Excavation Work and Interpretation: The Faunal and Human Remains - Structure and Chronology of Monte Bernorio Area 7 - Destruction of the Body, Commemoration in the Absence of a Corpse, and Visibility of the Mortuary Rite

    Evidence of the anomalous charge state 57Fe4+ in the nuclear decay of 57Co3+

    No full text
    The first observation of the elusive Fe4+ charge state coming from the nuclear decay of 57Co3+ has been found in the Mössbauer emission spectra of 57Co:La2Li0.5Co0.5O4. A Ti-doped sample was prepared in order to show that the Fe4+ fraction can be conveniently monitored. Both results were predicted on the basis of the electronic energy-band scheme of these oxides

    Magnetic order or charge-density wave in La2NiO4 by Mössbauer spectroscopy

    No full text
    Measurements of Mössbauer absorption spectra of 57 Fe : La 2 Ni O 4 at 297, 77, and 4.2 K provide evidence, at the lowest temperatures, of magnetic order in a sample containing 57 Fe 3 + -ion impurities and some La 2 + n Ni 1 + n O 4 + 3 n intergrowth. Mössbauer emission spectra of 57 Co : La 2 Ni O 4 at 77 and 4.2 K show magnetic order coexisting with paramagnetism in a sample containing a small concentration of 57 Co -ion impurities and some La 2 + n Ni 1 + n O 4 + 3 n intergrowth. These results are interpreted as evidence for competition between magnetic ordering and charge-density-wave formation among electrons of a narrow σ ∗ x 2 − y 2 band; intergrowths, impurities, and nonstoichiometry favor magnetic ordering

    Evidence of the anomalous charge state 57Fe4+ in the nuclear decay of 57Co3+

    No full text
    The first observation of the elusive Fe4+ charge state coming from the nuclear decay of 57Co3+ has been found in the Mössbauer emission spectra of 57Co:La2Li0.5Co0.5O4. A Ti-doped sample was prepared in order to show that the Fe4+ fraction can be conveniently monitored. Both results were predicted on the basis of the electronic energy-band scheme of these oxides

    Structural and magnetic characterization of the lithiated iron oxide LixFe3O4

    No full text
    The Rietveld profile‐analysis method is used to investigate the x‐ray diffraction pattern of lithiated Fe3O4. It is shown that, after exposure to air, pure magnetite coexists with a lithium‐inserted LixFe3O4 phase. The Mössbauer spectra at 300 and 4.2 K have been used to estimate the lithium content of the sample, the pure magnetite concentration, and the iron distribution over the available 16c and 16d sites of the spinel structure. Magnetization measurements from 4.2 to 120 K with an external magnetic field up to 150 kOe have been used to obtain the saturation magnetic moment, the magnetic anisotropy constants, and the susceptibility. It is concluded that a noncollinear spin structure should be present in Li0.5Fe3O4. These results indicate that there is no room‐temperature extrusion of iron even for x→2.0, but that on exposure to air LixFe3O4 samples with x>0.5 are oxidized at room temperature by delithiation

    Metallic state and the metal-insulator transition of NdNiO3

    No full text
    We report detailed measurements of the electrical resistivity, Seebeck coefficient, and differential scanning calorimetry across the metal-insulator (MI) transition ( T MI ≊205 K) of NdNiO 3 . As in the isostructural oxide PrNiO 3 , the transition is extremely hysteretic, consistent with the first-order character of the transition. Analysis of the data shows that metallic and nonmetallic phases coexist in a broad temperature interval (≊70 K). The electrical resistivity and Seebeck coefficients of the metallic state display a clear linear temperature dependence. These properties can be rationalized in terms of a Fermi gas picture of rather heavy electrons (effective mass of about 6 m 0 ). Some physical parameters of the gas are predicted. The entropy change across the MI transition has been measured and it has been used to predict a strong pressure dependence of the MI transition temperature: dT MI /dP≊-4.8 K/kbar

    Structural and magnetic characterization of the lithiated iron oxide LixFe3O4

    No full text
    The Rietveld profile‐analysis method is used to investigate the x‐ray diffraction pattern of lithiated Fe3O4. It is shown that, after exposure to air, pure magnetite coexists with a lithium‐inserted LixFe3O4 phase. The Mössbauer spectra at 300 and 4.2 K have been used to estimate the lithium content of the sample, the pure magnetite concentration, and the iron distribution over the available 16c and 16d sites of the spinel structure. Magnetization measurements from 4.2 to 120 K with an external magnetic field up to 150 kOe have been used to obtain the saturation magnetic moment, the magnetic anisotropy constants, and the susceptibility. It is concluded that a noncollinear spin structure should be present in Li0.5Fe3O4. These results indicate that there is no room‐temperature extrusion of iron even for x→2.0, but that on exposure to air LixFe3O4 samples with x>0.5 are oxidized at room temperature by delithiation

    Long-range order of Ni2+ and Mn4+ and ferromagnetism in multiferroic (Bi0.9La0.1)2NiMnO6 thin films

    Get PDF
    Epitaxial thin films of biferroic Bi1−xLax 2NiMnO6 have been grown on SrTiO3 001 substrates. High resolution electron microscopy, energy-loss spectroscopy and synchrotron radiation have been used to demonstrate that, under appropriate growth conditions, stoichiometric, and fully oxidized thin films with long-range order of Ni2+ and Mn4+ ions can be obtained, despite the presence of randomly distributed dissimilar cations Bi, La at the A-site. This ordering leads to Ni2+OMn4+ ferromagnetic interactions and its preservation in thin films is key for implementation of these biferroic materials in practical devices
    corecore