No abstract

Both α- and γ-zirconium phosphate were examined for use as ion exchangers for recovery of rare earth elements. Trivalent rare earth elements can be partially substituted for protons in the interlayer space, and γ-zirconium phosphate shows a much better ion exchange competency than α-zirconium phosphate. The exchanged cation of the rare earth elements might be related to different amounts of oxygen from P–OH and H2O, and these rare earth elements were thus positioned at a different separations from the zirconium phosphate layer. The radial structure function (RSF) curve from extended X-ray absorption fine structure data implied that the calibrated M–O distance and coordination number changed with the ionic radius. The calibrated M–O distances from RSF were 2.52, 2.42, 2.38, and 2.28 for La, Eu, Dy, and Yb, respectively. The coordination numbers of oxygen for Yb were approximately 7 and greater than 10 for La and Eu, respectively. These smaller coordination numbers for smaller cations may result from the strong interaction between the cations and the zirconium phosphate layer. The Debye–Waller factor also increased with an increase in the ionic radius. These factors show a strong relation to the coordination state of rare earth elements in the unit cell of the γ-zirconium phosphate and to the interaction strength.

No abstract

No abstract

This paper deals with the aerodynamic interference between two vehicles which are running in close proximity and are subjected to crosswind. Measurements of the aerodynamic drag, side force and yawing moment were performed at different wind angles and longitudinal and lateral distances between two vehicles. In crosswind, extreme proximity between the vehicles ahead and behind provides several peaks of aerodynamic drag, side force and yawing moment acting on the vehicles. When one vehicle passes the other one in crosswind, the large variation in these forces and moment leads to the danger of driving. Numerical results by the CFD show a good agreement with experimental ones. They reveal that the aerodynamic drag is influenced by airflow behind the other vehicle, and that the side force and the yawing moment are also influenced by complicated airflow structure due to the aerodynamic interference between two vehicles.