Coulomb accumulation points

In both nuclear and atomic physics there are compUcations with the notion of levels . Beyond a certain excitation energy the energy levels acquire an appreciable width, i.e. the levels no longer correspond to bounded states. In atomic physics there is an additional complication with the existence of Coulomb accumulation points in the spectrum. Therefore, one has to be careful when comparing the spacings of experimental levels with the theoretical predictions. But if only bounded states or sharp resonances away from accumulation points are included in the level spacing statistics, there should be no theoretical objections. 

Adhesive wear is characterized by transfer of material from one material to another during sliding as a result of the adhesive forces at the contact points. The transferred material accumulates until the surface forces cause wear particles to form 50). Because the rate at which polymeric material transfers depends on the bonding at the contact point — Coulombic and van der Waals — adhesive wear is usually small compared... 

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