The results of research devoted to formation of ordered arrays of particles during melting process of tin films on amorphous carbon substrate are given in the present work. Using scanning electron microscopy the histograms of particle size distribution are constructed for films of different mass thickness. The size dependences of the most probable radius of particles, which are formed during the melting process, and the half-width values of the corresponding histograms are obtained as well. The excess energy, which provides a decomposition of the initially continuous film into separate islands, is estimated and its size dependence is built. As shown, the melting process of films, which are condensed in island structures, provides larger filling coefficients in comparison with the melting process of initially continuous films.

The results of the study of melting of Bi-Sn and Pb-Sn polycrystalline layered film systems with the thickness of 200-400 nm on a substrate with temperature gradient are given. Multilayer (each layer is of 10-20 nm) and bilayer films (layers are of 100-200 nm) of the same total thickness have been investigated. Broadening of the melting range in all films and lowering of melting point in multilayer samples compared to the bilayer ones have been observed. The observed phenomena are discussed within existing thermodynamic concepts in consideration of interfacial energy of contacting layers of components and energy of grain boundaries in polycrystalline films.

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We have determined the comparative efficacy of the effect of cuprum and cobalt nano-particles (30-40 nm), humic acids in an ultra-fine state and mineral salts of these metals used as micro-fertilizers on plants growth and development at concentration from 0.01 till 1000 gr. per hectare norm of viability (gr./h.n.v.). We have conducted some bio-chemical investigations and studied activity of peroxydase and superoxide dismutase ferments in wheat roots and seedlings.The lab tests have determined concentrations when spring wheat plantlets growth and development slows down: for cuprum nano-particles -500 gr./h.n.v., cobalt -400 gr./h.n.v., copper sulphate and cobalt chloride -100 gr./h.n.v. The concentrations of 0.5-10 gr./h.n.v. cuprum and cobalt nano-powders have a well defined stimulating effect. The effect of using the metals nano-particles has been 8-12 % higher than that of the humic acids. Nano-particles have energy to activate metabolic cell processes of plants and concentrations up to 10 gr./h.n.v. can be recommended for the use in agrotechnology that is proved by field tests: wheat yield has increased under the humic acids per 7 %, cuprum and cobalt nano-particles per 17 % and 14 % correspondingly as compared with the control.Cuprum and copper oxide nano-powders (of different chemical substance) at concentrations 0.1 gr./h.n.v.-100 gr./h.n.v. have influenced activity of phytohormones of cytokinin, gibberellin, abscisic acid and indole acetic acids in wheat seedlings. The increase of cuprum nano-powder concentration in 100 times has not caused the decrease of wheat physiologic processes. For copper oxide nano-powders at concentration of 100 gr./ha the hormones activity changes from 22 to 53 % and the use of copper oxide at concentrations higher than 100 gr./h.n.v. is unreasonable. The wheat seeds treatment with 200 nm particles before planting has not changed morpho-physiologic and biochemical indexes as related to the control.

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