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An experimental protocol of preparation of homogeneous and nanocomposite chitosan (Ch) based membranes supported on polyamide-6 (PA6) films was developed and described in detail. Montmorillonite (MMT) and Cloisite 30B (C30B) nanoclays were used as nanofillers to improve mechanical properties of chitosan films. The surface, mechanical, and transport properties of PA6 supported Ch, Ch/MMT and Ch/C30B membranes were studied and compared with a pristine, non-supported chitosan membrane. Implementation of advanced analytical techniques e.g., SEM reveal the clays nanoparticles are well dispersed in the chitosan matrix. According to AFM images, composite chitosan/nanoclay membranes possess higher roughness compared with unfilled ones. On the other hand, an incorporation of clay particles insignificantly changed the mechanical and thermal properties of the membranes. It was also found that all membranes are hydrophilic and water is preferentially removed from EtOH/H2O and iPrOH/H2O mixtures by pervaporation. Supporting of chitosan and chitosan/nanoclay thin films onto PA6 porous substrate enhanced permeate flux and pervaporation separation index, in comparison to the pristine Ch membrane. Concerning separation factor (β), the highest value equal to 4500 has been found for a chitosan composite membrane containing Cloisite 30B contacting 85/15 wt % iPrOH/H2O mixture. The mentioned membrane was characterized by the normalized flux of 0.5 μm kg m−2 h−1. Based on the established data, it was possible to conclude that chitosan membranes are meaningful material in dehydration of azeotropic mixtures. Nevertheless, to boost up the membrane efficiency, the further modification process is required.

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Sour cherry is one of the most important fruit crops in Poland and cultivar is an important factor in its cultivation. The experiment was conducted in a commercial family orchard in a year characterized by a warm and wet spring and also by a very hot and dry summer. Fruit yields harvested from well fertilized 19-years old 'Kelleris 16', 'Nefris' and 'Łutówka' trees grafted on Mahaleb cherry and protected against pests using integrated plant protection system were medium high and of good quality, however productivity index of a tree was low. The fruits attained high weight and diameter and contained big amounts of sugars, vit. C, anthocyanins and flavonoids and medium amount of phenolic acids. Among anthocyanins the most important were cyanidin 3-glucosyl-rutinoside and cyanidin 3-rutinoside. Antioxidant activity of fruits measured as percent of DPPH inhibition was high and similar among compared cultivars. Łutówka was the most productive cultivar of medium leaf and fruit size and with fruits of highest vit. C and flavonoids content and lowest total sugars and monosaccharides content. The least productive cultivar was Nefris, though its fruits were the biggest and contained dry matter, soluble solids, anthocyanins and phenolic acids in the highest amounts of all and vit. C at the lowest level of all. Kelleris 16 was the medium productive cultivar characterized by widest leaf blades and smallest fruits. Content of total sugars and monosaccharides in its fruits was the highest and content of anthocyanins and phenolic acids was the lowest. Residues of dodine and thiacloprid determined in the fruits immediately after harvest were much lower than the permissible residue maximum level.