@eeived tuly ID PHIIY in (nl form epril PHD PHIPA It was found that irradiation of a water solution of NaCl with the diractometer DRON3-M (Russian device) had a large inuence on two-step processes of crystallization. The irradiation in the rst stage of crystallization of the solution produces metastable radicals of water and excited seeds, which stimulate a very fast crystallization after switching o irradiation. After the crystals reach a sucient size, the crystal growth can be explained by creation of vacancy-interstitial pairs in the growing crystal due to irradiation. The increase of linear dimensions of the growing irradiated crystals is proportional to the square root √ t of crystallization time because most important place in crystallization takes the ions diusion by irradiated vacancies.

Results of investigations of island amorphous selenium layers evaporated upon a carbon film are presented. The layers were heated at various temperatures. In all cases, selenium formed islands of almost perfectly hemispherical shape with various diameters. Such well-defined shape of the islands made it possible to calculate total mass of the islands. Experimental data indicates that heating of the layer causes an increase of the mass of islands up to 7 times in comparison with their mass prior to thermal processing. This is possible only if the islands grow by accepting atoms of the same kind adsorbed on the substrate. It follows that a part of the layer mass is accumulated in the gas adsorbed on the substrate. This part depends on the layer temperature, substrate material, evaporation rate, etc. Investigation of distribution of island diameters immediately after layer evaporation and during thermal processing of the layer allowed determination of conditions that are needed in order to be able to estimate defect density in the substrate from the measured density of the islands.

Dispersion coating layers consisting of hydroxypropylated starch, 0–30 pph of barrier-grade talc and 0–10 pph of styrene-butadiene latex were subjected to both positive and negative direct-current corona treatments utilizing a specially developed dynamic treatment unit. The effects of the surface composition (barrier coating) on the response to the direct current corona treatment were evaluated by measuring contact angles and determining the surface energy. The effects of corona treatment on the properties of the barrier coating were further determined by measuring the contact angle of rapeseed oil and the grease resistance. It was found that the grease resistance of the corona-treated barrier coatings was substantially lower than that of untreated samples, which was ascribed to holes caused by corona discharge strike-through and to chemical changes on the treated surfaces. The corona treatment lowered the surface energy of the coatings, as indicated by an increase in the contact angles of water and rapeseed oil. Changes in the dispersion part of the surface energy were recorded, particularly after positive treatment voltage, whereas a negative discharge led to greater changes in the polar part of the surface energy. X-ray photoelectron spectroscopy (XPS) tests revealed an increase in the proportion of talc at the surface after corona treatment, which indicates a migration caused by the applied electric field. The peak force tapping mode of an atomic force microscope revealed moderate topographical changes in the coatings and a decrease in surface elasticity, supporting the migration of talc particles. In addition, significant changes in the physicochemical properties of the untreated reverse side were observed.

Electrospinning is an efficient process for producing polymeric and hybrid nanofibers. There is, however, a lack of understanding concerning scalability of the process and in particular the production rate optimization. The electrospinning mass transfer intensity depends predominately on solution parameters, process parameters and the design of the equipment. These parameters influence the deposition intensity of the spinning process differently, but it is not known which factors dominate. The e‐spinning deposition intensity of polyethylene oxide, polyvinyl alcohol and their mixtures was investigated using a bubble foamed polymer solution surface to promote high mass deposition. Based on the measured properties of the solutions, a mathematical criterion was developed which made it possible to predict the electrospinning intensity of a given polymer solution. The proposed formula agrees with the experimental data and confirms that spinning intensity can be predicted from pre‐determined solution parameters. Using computer modeling, the weighting coefficients of the solution parameters have been determined, showing which parameter is the most important for the process intensity. The criterion and the same weighting coefficients were applied to the analysis of published data and it was found that they can be applied not only for electrospinning from the foamed surface but also from the free surface. A physical explanation of the criterion is proposed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42034.

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