The scaling of turbulence characteristics such as turbulent fluctuation velocity, turbulent kinetic energy and turbulent energy dissipation rate was investigated in a mechanically agitated vessel 300 mm in inner diameter stirred by a Rushton turbine at high Reynolds numbers in the range 50 000 < Re < 100 000. The hydrodynamics and flow field was measured using 2-D TR PIV. The convective velocity formulas proposed by Antonia et al. (1980) and Van Doorn (1981) were tested. The turbulent energy dissipation rate estimated independently in both radial and axial directions using the one-dimensional approach was not found to be the same in each direction. Using the proposed correction, the values in both directions were found to be close to each other. The relation ε/(N3·D2) ∞ const. was not conclusively confirmed.

Feasibility of a model of gas bubble break-up and coalescence in an air-lift column enabling determination of bubble size distributions in a mixer with a self-aspirating impeller has been attempted in this paper. According to velocity measurements made by the PIV method with a self-aspirating impeller and Smagorinski’s model, the spatial distribution of turbulent energy dissipation rate close to the impeller was determined. This allowed to positively verify the dependence of gas bubble velocity used in the model, in relation to turbulent energy dissipation rate. Furthermore, the range of the eddy sizes capable of breaking up the gas bubbles was determined. The verified model was found to be greatly useful, but because of the simplifying assumptions some discrepancies of experimental and model results were observed.

A continuous contact layer exists between the top and bottom layer of concrete composite reinforced floors. The contact layer is characterised by linear elasticity and frictional properties. In this paper a model of single degree of freedom of composite floor is determined. The model assumes that the restoring forces and the non-conservative internal friction forces dissipating energy are produced within the contact layer. A hysteresis loop is created in the process of static loading and unloading of the model, with the energy absorption coefficient being defined on this basis. The value of the coefficient is rising along with the growing stiffness of the composite.

A critical damping ratio is a parameter describing free decaying vibration caused by non-conservative internal friction forces in the contact layer and in the bottom and top layer. The value of the ratio in the defined model is rising along with the lowering stiffness of the element representing contact layer.

The findings resulting from the theoretical analyses carried out, including the experimental tests, are the basis for the established methods of determining the concrete layer state for reinforced concrete floors. The method is based on energy dissipation in the contact layer.

The purpose of the study was to estimate in 2012 range and degree of soil contamination due to local diesel fuel leakage spills that occurred in 1980 and from any subsequent activities in the vicinity of the scientific Polish Polar Station in Hornsund, Svalbard. The area of the study covered the immediate vicinity of station buildings including areas of the 1980’s fuel barrel storage depot and location of current fuel tanks. Results of the study were compared with a similar study performed in 1980. As of 2012, areas potentially contaminated covered 0.9 ha, which was a 50% decrease compared to 1980. The area contaminated with total petroleum hydrocarbons was extremely localized. Spread of petroleum hydrocarbons from 1980’s source of pollution investigated 32 years later showed that petroleum derived products were environmentally mobile. Concentrations of total petroleum hydrocarbons in surface soils of the unsaturated active layer above the permafrost decreased significantly mostly due to surface runoff and dispersion through ephemeral drainages. Concentrations of total petroleum hydrocarbons increased with depth through time in sandy soils on the flat area where the largest 1980’s fuel barrel depot was located.