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Research results on the synthesis of carbon nanotube arrays using a combined catalyst are pre sented. Thanks to optimal synthesis parameters such as temperature, the reagent flow rate, the concentration and type of organometallic compound, and the composition of the catalyst film, a new synthesis method for the arrays of carbon nanotubes (CNTs) of a given topology is developed. The influence of the size effects of topological elements on the characteristics of the CNT arrays is studied. The results of a statistical analysis and research into the CNT morphology by transmission and scanning electron microscopy are shown.

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A new method has been suggested for reconstruction of raindrop size distribution and ram intensity from the normalized spectra of acoustic signals measured with a cw bistatic Doppler sodar. A data processing algorithm has been constructed and successively used for real sodar data processing based on the analytical formulas derived in the Rayleigh approximation and with the use of the exact Mie formulas. The raindrop size spectra were reconstructed from the individual power spectra of signals recorded every 20 s and from the signal power spectra averaged over 2-, 3-, 5-, and 25-nun periods. This has allowed us to track the dynamics of the raindrop size distribution. The presence of the second maximum of the number density of large raindrops was established, whose position shifted with time from 0.3 to 1 mm. Our study has shown that the large raindrops were grouped in ensembles and the second maximum of raindrop size distribution was observed only periodically. The obtained results demonstrate that high-frequency cw bistatic sodars are very promising for measurements of ram.

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