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A study of selected features of Shan Tong variety of plantation paulownia and its wood properties. The study was conducted on three-year-old and representative paulownia tree of the Shan Tong variety, from a plantation in the Kujawsko-Pomorskie Voivodeship, Poland. The three-year-old paulownia tree was 4.2 m high and its diameter at butt level was of 11 cm. The tree provided material for the study from its three-year-old shoot, which was divided into three parts: leaves, branches and the main trunk. According to calculations, this typical paulownia tree (a three-year-old shoot) from a plantation accumulated 4.664 kg of carbon in the part above the ground level, which corresponds to the absorption of 17.101 kg of CO2 from the atmosphere. Taking into account the underground part of this plant, it can be estimated that it absorbed over 30 kg of CO2 (on average, ca. 10 kg CO2 per year). The density of paulownia wood in absolute dry state was ca. 250 kg/m3. The width of annual growth rings was ca. 1.5 cm. This kind of wood is highly porous, with porosity of about 85% (good thermal insulation), and at the same time it has favourable resistance properties characterized by the modulus of elasticity of 4.05 GPa.

This study analyzes the effects of manufacturing parameters such as the temperature and heating time on the shape and size of high-aluminum-phase precipitates produced from a 95.5 wt pct Al and 4.5 wt pct Fe powder mixture. The samples were prepared by powder metallurgy, and the changes in the heat flux during the simulation of the sintering process by differential thermal analysis were recorded to determine the temperature of the transformation. To identify the resulting structures, microscopic observations (scanning electron microscope) and chemical composition analyses were performed simultaneously. The distribution and shape of the resulting high-aluminum-phase precipitates were determined. Microhardness measurements were also performed, and Meyer's law and Kick's similarity law were applied to the results to analyze the influence of the high-aluminum phases on the reinforcement of the aluminum matrix.