Institution: | 1. University of Chemical Technology and Metallurgy, Department of Metallurgy of Non-Ferrous Metals and Semiconductor Technologies, 8 Kl. Ohridsky Blvd., 1756 Sofia-56, Bulgaria;2. Technical University of Sofia, Department of Thermal and Nuclear Power Engineering, 8 Kl. Ohridsky Blvd., 1000 Sofia, Bulgaria |