In order to diminish the brittleness of pure feather keratin films, in this research, blended films with improved physical properties were prepared using konjac glucomannan (GM). The influence of the GM ratio in the blended films on their final characteristics was studied. The chemical composition, thermal properties, as well as water swelling, moisture absorption and surface hydrophilic/hydrophobic character of the films were analyzed using Fourier-transform infrared spectroscopy, thermogravimetry, optical microscopy and goniometry. The results showed that konjac glucomannan improved the breaking strength and Young's modulus, as well as the water and moisture sorption and surface water contact properties of the blended films. The present study revealed the great potential of combining waste feather keratin and konjac glucomannan for improving the essential characteristics of films developed for different fields of application, such as in food packaging (dry or wet food packaging concepts) or medical applications.

Within the frequency range 10…106 Hz, the frequency dependences of the real (ε') and imaginary (ε") components of the complex dielectric permittivity of medical thermal indicators based on polyvinyl acetate and mixtures of cholesteric liquid crystals have been studied. In them, the selective reflection of electromagnetic waves visible to the human eye occurs at normal (36.6 °C) and elevated (38.2 °C) human body temperatures. Being based on the comparison of the ε' frequency dependences for the studied in this work dispersions of nematic liquid crystals prepared using the same technology and with the same polymer, it has been shown that, already on the basis of analysis of frequency dependences for ε', it is possible to ascertain the difference in characteristics for two types of thermal indicators. From the comparison of frequency dependences for ε", the main reasons of a difference between dielectric properties of the investigated medical thermal indicators for various temperatures of a human body have been ascertained.

Constructions of integral equations to the wave function of particle systems in bound state have been proposed in this work. We obtain the kernel of the Fredholm type integral equation for an odd number of particles in explicit form. Besides, an integral equation that can be attributed to the class of Volterra integral equations was built. Their equivalence to known equations in limiting cases has been shown.