Balther of Säckingen, Bishop of Speyer, Composer of Chants for St Fridolin ca. 970

Balther of Säckingen was a remarkable scholar, writer and composer, who was born about 930, made bishop of Speyer in 970, and died in 986 or 987. Educated at the famous monastery in St. Gallen, he went as a wandering student in search of learning as far as North Spain. He had a special veneration for St Fridolin, founder of a convent in Säckingen. On his travels Balther found a copy of a Life of St Fridolin, memorized it, wrote it down on his return home, composed chants to be sung on the feast day of the saint, and sent both the Life (vita) and the chants (historia) to one of his former teachers at St. Gallen for approval. Balther says he composed them “per musicam artem”, “according to the art of music”. This paper tells how Balther’s chants came to be composed and compares them with others in order to understand what was considered to be “musical art” around 970

Incorporation of square-planar Pd2+ in fluorite CeO2 : hydrothermal preparation, local structure, redox properties and stability

The direct hydrothermal crystallisation at 240 °C of Pd2+-containing ceria is investigated to study the extent to which precious metal dopants may be introduced into the cubic fluorite lattice. Samples of composition Ce1−xPdxO2−δ, where 0 ≤ x ≤ 0.15 can be produced in which Pd is included within the CeO2 structure to give a linear lattice expansion. Attempts to produce higher Pd2+-substitution result in the formation of PdO as a secondary phase. Ce and Pd were determined to be in the +4 and +2 oxidation states, respectively, by X-ray absorption near edge structure, suggesting oxide deficiency as the mechanism of charge balance. Extended X-ray absorption fine structure (EXAFS) analysis at the Pd K-edge reveals that Pd2+ has local square-planar coordination, as expected, and that a structural model can fitted in which the average fluorite structure is maintained, but with Pd2+ sitting in the square faces of oxide ions present in the local cubic geometry of Ce. This model, consistent with previous modelling studies, gives an excellent fit to the EXAFS spectra, and explains the observed lattice expansion. Transmission electron microscopy analysis shows that Pd is well dispersed in the nanocrystalline ceria particles, and in situ powder XRD shows that upon heating in air the samples remain stable up to 800 °C. H2-TPR shows that Pd-substitution leads to low temperature (<200 °C) reduction of the oxide, which increases in magnitude with increasing Pd-substitution. On prolonged heating, however, the Pd is lost from the ceria lattice to give dispersed Pd metal, suggesting an inherent instability of Pd-doped CeO2

Faculty Roles and Collective Responsibilities

Virginia Commonwealth University is into the fourth year of implementation of Faculty Roles and Rewards Policy. The policy is deceptively simple. It is producing, however, a change in the institutional understanding of the roles of faculty, department chairs, and departments. The authors discuss the implementation of the policy from the perspectives of a college, a department, and three individual faculty member

Incorporation of Sb5+ into CeO2 : local structural distortion of the fluorite structure from a pentavalent substituent

Hydrothermal crystallisation of CeO2 from aqueous sodium hydroxide solution at 240oC using CeCl3·7H2O in the presence of hydrogen peroxide with addition of either SbCl3 or SbCl5 yields polycrystalline samples of antimony-containing ceria directly from solution. Powder X-ray diffraction shows a contraction of the cubic lattice parameter with increasing Sb content, and also a broadening of Bragg peaks, from which Scherrer analysis yields crystallite domain sizes of 5 - 20 nm. Scanning transmission electron microscopy provides consistent results with observation of highly crystalline particles of a few nm in diameter. X-ray absorption near edge structure spectroscopy at the Ce LIII and Sb K edges reveals the presence of Ce4+ and Sb5+ in the solids. To balance charge the presence of co-included Na is proposed, corroborated by elemental analysis. The general chemical formula of the materials can thus be written as (Ce1 xSbx)1 yNayO2-δ (where x < 0.4 and y ≥ x/3). Sb K-edge extended X-ray absorption fine structure spectroscopy of the substituted ceria samples shows that the local structure of Sb resembles that in NaSbO3, where six-coordinate metal sites are found, but with evidence of a longer interatomic correlation due to surrounding Ce/Sb atoms in the fluorite structure; this implies that the Sb is displaced from the ideal eight-coordinate site of the fluorite structure. This structural distortion gives materials that are unstable under reducing conditions, coupled by the ease of reduction to elemental antimony, which is extruded leading to phase separation