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The heat capacity and enthalpy of fusion of calcium nitrate tetrahydrate, and magnesium nitrate hexahydrate were determined from 234.15 K to melting temperature with point of view of energy storage. Determined values were used for the calculation of entropy and Gibbs energy in the experimental temperature range. Melting point and enthalpy of fusion of calcium nitrate tetrahydrate is 43.9 ± 0.3 °C and 36.6 ± 0.2 kJ mol One solid-solid phase transformation was observed for the magnesium salt at 72.5 ± 0.9 °C with enthalpy of transition 3.1 ± 0.2 kJ mol -1 . The accumulated energy composed of sensible and latent heat is 43.4 and 63.8 kJ mol -1 for the hydrated calcium and magnesium nitrate, respectively. The kinetics of solid-solid phase transformation for magnesium salt was studied under non-isothermal conditions by DSC and the process was described using autocatalytical model with parameters in the range of 0.50 -0.85 for m and range of 2.58 -1.48 for n, respectively.

The dehydration of calcium oxalate trihydrate was studied using DSC method and open sample crucibles. The dehydration proceeds in two steps where first two molecules of water are released around 80 °C and consequently the last molecule of water is released at a temperature around 130 °C. The kinetic analysis of overlapping peaks was done and the apparent activation energy, pre-exponential factor and kinetic exponents of kinetic model (reaction order model) were evaluated for both effects.

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The paper deals with multi-robot centralized autonomous area exploration of unknown environment with static obstacles. A simple reasoning algorithm based on preassignment of routing priority is proposed. The algorithm tracks the frontiers and assigns the robots to the frontiers when the robots fall into a trap situation. The algorithm is simulated with various multi-robotic configurations in different environments and compared with performance indices in the MATLAB simulation environment.