Spatial distributions of desorbing products in steady-state NO and N2O reductions on Pd(110).
The angular and velocity distributions of desorbing product N(2) were examined over the crystal azimuth in steady-state NO+CO and N(2)O+CO reactions on Pd(110) by cross-correlation time-of-flight techniques. At surface temperatures below 600 K, N(2) desorption in both reactions splits into two directional lobes collimated along 41 degrees -45 degrees from the surface normal toward the [001] and [001] directions. Above 600 K, the normally directed N(2) desorption is enhanced in the NO reduction. Each product desorption component, as well as CO(2), shows a fairly asymmetric distribution about its collimation axis. Two factors, i.e., the anisotropic site structures and the reactant orientation and movements, are operative to induce such asymmetry, depending on the product emission mechanism.
Normal Modes at Surfaces
Vibrational spectroscopic techniques have played a major role in extending our understanding of structure, bonding, and reactivity in all phases of matter. Only relatively recently has it become feasible to apply these powerful experimental methods to the study of surfaces and species adsorbed at those surfaces. Vibrational spectroscopy has the great advantage over many other surface-sensitive spectroscopies that one has available a vast body of data, already collected and understood, for gas phase, liquid phase, and solid systems. The concept of group frequency is of great importance. Similarly, our knowledge of spectroscopic activity in the gas phase and in three-dimensional crystalline arrays is well developed and amenable to the powerful methods of group theory in its interpretation.
Food security among asylum seekers in Melbourne
Objectives: This research explores food insecurity among asylum seekers who are members of the Asylum Seeker Resource Centre (ASRC) in Melbourne, Australia.