The purpose of this study was to assess the potential for biocomposite films to biodegrade in diverse climatic environments. Biocomposite films based on polyethylene and 30 wt.% of two lignocellulosic fillers (wood flour or flax straw) of different size fractions were prepared and studied. The developed composite films were characterized by satisfactory mechanical properties that allows the use of these materials for various applications. The biodegradability was evaluated in soil across three environments: laboratory conditions, an open field in Russia, and an open field in Costa Rica. All the samples lost weight and tensile strength during biodegradation tests, which was associated with the physicochemical degradation of both the natural filler and the polymer matrix. The spectral density of the band at 1463 cm⁻¹ related to CH₂-groups in polyethylene chains decreased in the process of soil burial, which is evidence of polymer chain breakage with formation of CH₃ end groups. The degradation rate of most biocomposites after 20 months of the soil assays was greatest in Costa Rica (20.8–30.9%), followed by laboratory conditions (16.0–23.3%), and lowest in Russia (13.2–22.0%). The biocomposites with flax straw were more prone to biodegradation than those with wood flour, which can be explained by the chemical composition of fillers and the shape of filler particles. As the size fraction of filler particles increased, the biodegradation rate increased. Large particles had higher bioavailability than small spherical ones, encapsulated by a polymer. The prepared biocomposites have potential as an ecofriendly replacement for traditional polyolefins, especially in warmer climates.

Nowadays, the development and research of nonwoven medical fibrous materials based on biopolymers is an area of a great practical interest. One of the most promising methods for producing nonwoven materials with a highly developed surface is electrospinning (ES). In this article, the possibility of efficient sterilization of ultrathin fibers based on polyhydroxybutyrate (PHB) by ozone treatment was considered. The purpose of this work was to select the most optimal morphology of nonwoven materials for medical purposes and to establish the correlation between the supramolecular structure and the physical properties of fibrous materials while under the influence of an ozone sterilization process.

Biocomposites based on low density polyethylene (LDPE) and birch wood flour (WF) were investigated. The mechanical properties and water absorption capacity were examined depending on the particle size of a filler in biocomposites. The aim of the paper is the investigation of composite properties depending on the filler particle size. The filler particle sizes were 0–80 µm, 80–140 µm, 140–200 µm, and 0–200 µm. The tensile strength of composite samples varied within the range 5.7–8.2 MPa. Elongation at break of composites varied within the range 5.1–7.5%. Highest mechanical properties were found in composites with the lowest filler fraction. Highest water absorption was observed in composition with a complex fraction of the filler. The influence of the filler particle size on composite properties was shown. It was found that an increase of the filler particle size decreases mechanical parameters and increases water absorption.

Studies on polymer composites based on polyolefins (polyethylene; polypropylene; their mixtures; propylene–ethylene, ethylene–vinyl acetate, and ethylene–octane copolymers) and various natural compounds were reviewed. The reviewed studies analyzed the influence of various factors on the formation of the biodegradable properties of polyolefins.

Recently, thulium has been condensed to Bose-Einstein condensate. Machine learning was used to avoid a detailed study of all obstacles, making cooling difficult. This paper analyzes the atomic loss mechanism for the 532-nm optical trap, used in the Bose-condensation experiment, and compares it with the alternative and more traditional micrometer-range optical dipole trap. We also measured the scalar and tensor polarizability of thulium at 1064 nm, which were found to be $167\pm 25$ a.u. ($275\pm 41\times {10}^{-41}\mathrm{F}{\mathrm{m}}^2$) and $-4\pm 1$ a.u. ($7\pm 2\times {10}^{-41}\mathrm{F}{\mathrm{m}}^2$), respectively.