Exchange mechanisms for self-diffusion on aluminium surfaces

We present the results of molecular dynamics simulations and energy minimisation calculations for the diffusion of an Al adatom on Al(110) and Al(100) surfaces using a realistic many-body potential. For the Al/Al(110) system, the adatom motion is found to involve both a simple atomic-hopping mechanism, for displacements along the surface channels, and an atomic-exchange mechanism for displacements across the channels. On the (100) surface diffusion proceeds by an exchange mechanism. The transition state for this process is stabilised by strong covalent bonding.     

Beyond comparisons—the role for the operational researcher in benchmarking

This paper explores the possible roles for the operational researcher in best practice benchmarking. It describes the range of activities which are carried out in the name of benchmarking, locates this approach in the broader context of performance improvement, and notes some critical concerns including the need to adopt a contingency approach to performance improvement. The paper concludes by encouraging operational researchers to contribute their professional skills to enhance the effectiveness of benchmarking.     

Fundamental units in rhenium carbonyl fluorides and other carbonyl fluoride systems

Summary An attempt is made to understand the nature of carbonyl fluorides and carbonyl fluoride complexes. It is surmised that carbonyl fluorides exist with only certain, specific, stable configurations which contain particularly stable units. The important building blocks for the chromium, manganese, iron, cobalt, copper and nickel triads are predicted.     

Rapid and effective labeling of brain tissue using TAT-conjugated CdS:Mn/ZnS quantum dots

TAT (a cell penetrating peptide)-conjugated CdSratioMn/ZnS quantum dots (Qdots), intra-arterially delivered to a rat brain, rapidly (within a few minutes) labeled the brain tissue without manipulating the blood-brain-barrier (BBB). Qdot loading was sufficiently high that it allowed a gross fluorescent visualization of the whole rat brain using a low power hand-held UV lamp. Histological data clearly showed that TAT-conjugated Qdots migrated beyond the endothelial cell line and reached the brain parenchyma. Qdots without TAT did not label the brain tissue confirming the fact that TAT peptide was necessary to overcome the BBB. The present study clearly demonstrated the possibility of delivering a large amount of Qdot-based imaging agents to the brain tissue.