1,721,035 research outputs found
Structural investigation of high-Tc superconductor EuBa2Cu3Oy by microRaman spectroscopy
No full textPolycrystalline EuBa2Cu3Oy (EuBCO) samples with various oxygen contents (y 6.25, 6.38 and 6.8) have been analysed by
means of microRaman spectroscopy. The usual Raman features of REBa2Cu3Oy high temperature superconductors (RE Y,
Eu, Sm, Er1⁄4) have been con®rmed also for EuBCO. A correlation between the crystal structure and the conductivity properties
as a function of the oxygen content has been established by studying in detail the features of the different Raman spectra. In
particular, the analysis of the peak pro®les of lattice vibrations involving oxygen atoms provides important information to
understand the anomalous superconducting properties found in the sample with y 6.38. In addition, the appearance in the
superconducting samples of a new mode centred at 223 cm21 may be correlated to ordering phenomena which have been called to justify the conductivity results
Correlation between hole density and oxygen excess in the Bi2Sr2CaCu2O8+d superconductor
No full textThe Role of Dislocations in the Thermal Dehydration of Lithium Formiate Monohydrate
No full textThe kinetics of lithium formate monohydrate dehdration (single crystal sample) has been investigated at constant temperature, from 317 K to 353 K, under dynamic vacuum both optically and thermogravimetrically
Kinetic Parameters from Thermogravimetric Data
No full textThe differential method of Achar, Brindley and Sharp and the integral one of Coats and Redfern are applied to the dehydration of BaB2 * H2O and HCOOLi*H2O and the kinetic parameters so obtained are compared with those deduced isothermally
Crystal Data for Ferric Molybdate: Fe2(MoO4)3
No full textIndexed powder patterns of the ferric molybdate in its monoclinic and orthorhombic forms are given
Kinetics of BaBr2·2H2O Dehydration: Comparison Between Isothermal and non-Isothermal Methods
No full textFor the reaction of dehydration of BaBr2 with a different content of water molecules, a comparison was made between the experimental non-isothermal alpha vs time curves and those calculated on the basis of a isothermal study. For low heating rates, the two data sets are in good agreement
Oxygen Chemical Diffusion Coefficient in Manganite Thin Films by Isothermal Electric Resistivity Measurements
No full textChemical Diffusion in the Bi, Sr, Ca, Cu/O System: The Kinetics and Mechanism of the Solid-State Synthesis of a Single-Phase “2212” Material.
No full textβ-Aluminas and Water: A Comparison of Mixed Li - Na and Pure Li and Na β - Aluminas
No full textTG, DSC and X-Ray measurements were made to characterize the water absorption process by Li (50%) - Na (50%) beta alumina. The equilibrium water content, dehydration enthalpies and lattice parameter values have been determined and compared with those previously obtained for pure Li and Na beta-aluminas
- …
