Chitosan is a promising environment friendly active polymer packaging material due to its biodegradability, exceptional film forming capacity, great mechanical strength, appropriate barrier property along with intrinsic antioxidant and antimicrobial features. Bifunctional reagent was used for producing water insoluble chitosan films. Biopolymeric films crosslinked by Genipin (Gp), which is a reagent of natural origin, should have high potential in food packaging. The influence of the ratio of functional groups in the chitosan-Gp system on film absorption in the visible and ultraviolet regions of the spectrum, sorption, physical, and mechanical properties of the films has been studied. The degree of chitosan crosslinking in the films obtained from solutions containing Gp was estimated using the experimental data on film swelling and water vapor sorption isotherms. It is demonstrated that crosslinking with genipin improves swelling, water resistance, and mechanical properties of the films.

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Various magnetic properties of amorphous Fe-Y alloys at finite temperatures such as the densities of states, local magnetic moments, susceptibilities, and the magnetic phase diagram have been investigated on the basis of the finite-temperature theory of amorphous magnetic alloys. It is found that the calculated magnetization, distribution of local moments, susceptibilities, and magnetic phase diagram in the most random atomic configuration show a spin-glass phase, a re-entrant spin-glass phase, ferromagnetism, and paramagnetism with reducing Fe concentration. These results describe qualitatively the experimental data for the melt-spun Fe-Y alloys. It is verified that the nonlinear magnetic couplings between Fe local moments and the large-amplitude fluctuations of local moments due to structural disorder result in the spin glass in the Fe-rich region. The decrease of the average coordination number of the Fe atom due to the large difference in atomic size between Fe and Y atoms, on the other hand, stabilizes the ferromagnetism at lower Fe concentrations. The difference in magnetic phase diagram between the melt-spun and the sputtered Fe-Y alloys is interpreted in terms of that between the atomic short-range orders. †

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