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Thermally stable nanoporous polymer films have been created as promising materials for membrane technologies. Thermosetting Cyanate Ester Resins (CERs) and linear polyurethane (LPU) were combined by stepwise thermal curing, and the films of resulting hybrid polymers were irradiated with α-particles followed by chemical etching. Well-defined highly regular nanoporous structures were developed in the films as evidenced by using SEM. No significant changes in chemical structure of the polymer systems obtained after α-irradiation were observed by FTIR spectroscopy measurements. The polymer films obtained on the basis of hybrid networks with the CER/LPU composition equal to 90/10 wt.% had quite narrow pore diameter distribution with average pore diameters around 12 nm. DSC and TGA measurements showed that the thermal characteristics of the nanoporous films were sufficiently high (Тg ~ 167 °C to ~199 °C, Тd5% ~ 293-359 o C, and Тd max ~ 429-457 o C). The CER/LPU nanoporous thermosetting materials demonstrated effective gas transport properties tested with gases, such as О2, СО2, N2, and СН4. The combination of an additional sensitization step using -rays and longer time of chemical etching improved the properties of the nanoporous systems developed. Such materials open the way to numerous applications, for example, as ultrafiltration membranes for advanced technologies, especially under extreme conditions.

The magnetic particles in the water-based magnetic uids were sterically stabilized by natrium oleate to prevent their agglomeration and consequently the adsorption of poly-ethylene-glycol (PEG) was carried out to improve the biocompatibility of the magnetic particles. Two sets of samples were prepared. The rst set of the samples was with dierent molar weight of PEG (Mw = 400, 1000, 10 000 and 20 000) at the constant weight ratio of PEG/Fe3O4 = 0.25 and the second one was with dierent weight ratio of PEG/Fe3O4 and constant molar weight of PEG (Mw = 1000). The samples were irradiated with 20 Gy. The same reduction of saturated magnetization (about 10%) after electron irradiation with 20 Gy was observed for all prepared samples.

The results of implementing equipment qualification are analyzed. Such equipment is critical for the nuclear and technical safety of domestic nuclear power plants that are especially important for the implementation of the Program for extending the terms of out-of-project operation of power reactors that are capable of being used as powerful sources of electricity. Based on the comparison of published reliability indicators of domestic nuclear power plants before and after implementing the qualification, it is shown that still there are problems to be solved. The perspective of further enhancing the reliability of the operation of domestic nuclear energetics is considered, by implementing radiation functional testing methods that are been developed at the INR NAS of Ukraine for a long period. The basis of this method is detailed research and operational control of all processes that occur in critical equipment in any operating modes of nuclear reactors to form a resource history of the equipment and to provide operational information about the remaining resource and the expected time of its failure to an on-line object operator.