a study of a ventilation system with a local recirculating diffuser was carried out. A three-dimensional model of the office space has been built. Using the STAR-CCM + hydrodynamic computing complex, a numerical simulation of the ventilation system has been performed. The calculation results are analyzed, the advantages of the investigated system are given.

Keywords: ventilation systems, local recirculating diffuser, indoor air quality, energy saving, numerical simulation, STAR-CCM +

In this paper a systematic study of individual single-walled and multi-walled carbon nanotubes was performed by Raman spectroscopy and high-resolution electron microscopy. We have presented the geometrical and electronic structure analysis on the examples of two tubes: individual single-walled and double-walled nanotubes. The role of different environmental effects and their influence on the final structure assignment are discussed. Moreover, we have shown that the Raman spectroscopy gives reliable estimations of the nanotube diameters and the conductivity. Given a non-destructible character of Raman spectroscopy, we may conclude that it is one of the most efficient methods for structure analysis of carbon nanotubes.

Keywords: Carbon nanotubes, Raman spectroscopy, electron microscopy