The kinetics of ozone absorption by fine graphite powders at 208C, the behavior of unpaired electrons of the graphene conjugated systems, and IR spectra of surface functional groups were studied. It was shown that ozone reacts with six-membered cycles at the graphite surface. After one-sixth of the accessible surface six-membered cycles were consumed, the reaction slows down sharply, probably due to the inductive influence of the functional groups formed, the reaction leads to a significant loss of the sample's mass. The observed changes of the ESP spectra in the ozonation process are indicative of free radicals localization at the surface layers, increase radical concentration and its transformation to peroxide radicals. The reaction of ozone with a graphite surface is accompanied by formation of local zones of destruction, which decrease the reactivity of the neighboring areas to ozone and thereby protect the remaining graphite surface nanostructures from further decomposition. The similarities and differences between graphite and fullerene C 60 nanostructural units in reactions with ozone were considered.

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The aim of this work was development of electron probe microanalysis (EPMA) technique suitable for composition determination of nanoscale layers. Proposed technique allows to determine the content of thin layers lying beneath the surface including single quantum wells (SQWs). The method is based on Monte‐Carlo numerical simulations. Application of this technique to the nitride heterostructures with SQWs and multiple quantum wells (MQWs) was demonstrated. Peculiarities of the method are discussed. Electron trajectories in GaN sample with In0.1Ga0.9N single quantum well. Simulation was made by Monte‐Carlo method.

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