The width and thickness of the analyzed kernels were small compared with the length, and bulk densities were also moderate. The yield point force values of the two hard varieties were 2.2 times higher than the values of the soft variety, at a moisture content of 0.136 kg kg(-1) for Simonida, 0.133 kg kg(-1) for Dragana and 0.141 kg kg(-1) for NS 40S.

This study reviews test results for a biomass-fired hot water boiler with a nominal boiler thermal power of 120 kW. In the experiments, prismatic wheat straw bales were used as biomass. The impact of the quantity (220, 290, 360 and 430 m 3 h −1 ) of inlet air fed to the boiler firebox was continuously monitored. This was to examine the influence of the quantity of inlet air and recirculation (0, 16.5 and 33%) of combustion products on the boiler thermal power and boiler energy efficiency. Thus, the following mathematical models and formulas were presented: correlation between boiler thermal power and bale residence time; bale mass loss during the combustion process; correlation between boiler energy efficiency and bale residence time. Mathematical models were obtained by using experimental data and by applying nonlinear regression analysis. Adjustment evaluation of mathematical models with experimental data was performed based on the determination coefficient, t-test and F-test. Increase the amount of air throughout the firebox produced boiler thermal power increase and bale residence time decrease. It was shown that combustion products recirculation of 16.5% partly improved boiler characteristics, while the recirculation of 33% did not, comparing with the case without recirculation.

Two methods for estimation of the surface area and volume of a Williams pear quarter provides the focus of this study. The heat energy needed for the drying process depends, in part, on the surface area. The first method involved multiplying the number of pears by the average surface area or volume. The second method involved calculating the surface area and volume of each pear quarter based on the pear length only, as described in the proposed algorithm. It was based on significant correlation between pear length and points on the upper bounder of the pear as well as on integral calculus.

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Stereology, an interdisciplinary field that enables three-dimensional interpretation of planar sections, contains several methods for evaluation of quantitative parameters. The existing leaf sampling procedures were modified and adapted for compound, trifoliate leaves. The similar sampling method could also be applied on other types of compound leaves. Using Trifolium species as model species, we suggested the new way of application of this method in agronomy -precise determination of volume densities of indigestible lignified tissues (which determines forage digestibility), and of chlorenchyma and intercellulars (important for the photosynthesis). Comparison of the results obtained by classic anatomical analysis of leaf cross sections with the results of stereological analysis showed that both methods could be successfully applied for analysis of compact tissues (epidermis, vascular and mechanical). For the tissues that contained intercellulars (palisade and spongy), stereological method gave more precise results, as it enabled separate determination of volume density of intercellulars. A further advantage is that several leaf segments are analyzed and observed from four different angles. The obtained results opened new possibilities of application of stereological method in botanical and agricultural research, especially in prediction of digestibility and nutritional value of forages.