A simple ten-parameter interatomic potential model is described that is capable of accurately reproducing the static and dynamical properties of complex oxides. The accuracy of this model stems from the crystal-chemical bond-valence theory of ionic and covalent bonding. The development of a specific variant of this model for ferroelectric PbTiO3 sPTd is discussed in detail, and comparison of th...

Magnetic oxides are naturally occurring minerals. In order to understand their unique properties and their utilization in technological applications, one must fully understand the correlation between chemistry, structure, particle size and processing. Among the broad classification of magnetic oxides, the spinel ferrites gain much importance because of their low cost, high magnetic permeability...

Palladium catalysts containing Pd(II) supported on Al2O3 and alumina-based mixed oxides, Al2O3-ZrO2, Al2O3-CeO2, and Al2O3-Fe2O3, are very effective in the Heck coupling of iodobenzene with cyclohexene in DMF solution. The best results, up to 81% of monoarylated products with a selectivity to 4-phenylcyclohexene (3) close to 90% were obtained with KOH as a base. The catalytic activity of pallad...

Mixed oxides have received remarkable attention due to the many opportunities adjust their interesting structural, electrical, catalytic properties, leading a better, more useful performance compared basic metal oxides. In this study, mixed NiO/ZnO/Al2O3 were synthesized in single step via ultrasonic spray pyrolysis method using nitrate salts, and temperature effects of process investigated (40...

We present different effective-field and cluster-variation treatments of the magnetic spin-: Ising model for a fraction x of frozen-in or quenched non-magnetic impurities. The resulting picture for the critical curve. magnetisation, energy, specific heat and susceptibility is simple and compares very well with Monte Carlo and experimental data. Our results can thus be useful in the analysis of ...

The production of small quantities of Fe(II) during the initial phase of microbial Fe(III) reduction greatly increased the amount of Fe(III) that could be extracted from freshwater sediments with oxalate. This finding and other evidence suggest that the oxalate-extractable Fe(III) that is unavailable for microbial reduction in anoxic sediments is not in the form of mixed Fe(III)-Fe(II) forms, a...

A new class of zirconia supported mixed metal oxides (ZnO-TiO(2)-Nd(2)O(3)/ZrO(2) and ZnO-SiO(2)-Yb(2)O(3)/ZrO(2)) has demonstrated the ability to convert low quality, high free fatty acid (FFA) bio-oils into biodiesel. Pelletized catalysts of ZrO(2) supported metal oxides were prepared via a sol-gel process and tested in continuous flow packed bed reactors for up to 6 months. In a single pass,...

Water electrolysis is an important route to large-scale hydrogen production using renewable energy, in which the oxygen evolution reaction (OER: 2H(2)O → O(2) + 4H(+) + 4e(-)) causes the largest energy loss in traditional electrocatalysts involving Ru-Ir mixed oxides. Following our previous mechanistic studies on the OER on RuO(2)(110) (J. Am. Chem. Soc. 2010, 132, 18214), this work aims to pro...

The single-site Solvation, Bond Strength, and Electrostatic (SBE) model accounts for the anomalous position of silica onthe surface acidity versus aqueous acidity correlation developed for metal oxides, by considering the solvation energy change in the protonation reaction implemented through the dielectric constant (1/epsilon(k)) and the electrostatic energy change through the Pauling bond str...