The synthesis and characterization of polyethylene−polyester block and graft copolymers and their potential as compatibilizers in polyethylene-based polymer blends are being described. The various routes to functionalized polyethylenes and the corresponding block/graft copolymers have been compared and evaluated for their scalability to industrial scale production. Hydroxyl chain-end and randomly OH-functionalized HDPE as well as randomly OH-functionalized LLDPE were employed as macroinitiators for producing the corresponding block and graft copolymers. These materials were prepared using two different strategies. The graf ting f rom approach entails catalytic ring-opening polymerization of lactones, i.e., ε-caprolactone and ω-pentadecalactone and hydroxyl-functionalized polyethylenes as macroinitiator. The alternative graf ting onto approach involves the preparation of block and graft copolymers via simple and convenient transesterification of polycaprolactone or polypentadecalactone with OH-functionalized polyethylenes. The copolymers were characterized in terms of their molecular weight (SEC), chemical structure (liquid state NMR), topology (MALDI-ToF-MS), supramolecular assembly (solid state NMR), and thermal properties (DSC analysis). The applied techniques for synthesizing the copolymers allow preparation of the products with sufficiently high molecular weight of the final materials. The copolymers were tested as compatibilizers for polyethylene/polycarbonate blends. As proven by SEM analysis, addition of the compatibilizers resulted in a significant improvement of the blend morphology.

To methods of analysis of odor of volatile organic compounds have been compared: classical sensory analysis and electronic nose technique. Eight volunteers participated in two-week classical sensory tests. The instrumental odor analysis involved a prototype of 6-sensor electronic nose designed by the authors. This device provided higher reproducibility and reliability of the results as compared to the ones obtained via the sensory analysis. Three compounds of specific odor and differing in chemical structure were utilized in the studies: 1-propanol, benzaldehyde and 2,3-butanedione. Aqueous solutions of the compounds and their mixtures were prepared at three concentration levels: 50 ppb, 1 ppm, 50 ppm v/v. The electronic nose technique, unlike the classical sensory analysis, made it possible to differentiate between particular solutions below the level of odor perceptibility and also allowed differentiation between the solutions of similar odor intensity reported by the volunteers.

Spelling error correction is an important problem in natural language processing, as a prerequisite for good performance in downstream tasks as well as an important feature in user-facing applications. For texts in Polish language, there exist works on specific error correction solutions, often developed for dealing with specialized corpora, but not evaluations of many different approaches on big resources of errors. We begin to address this problem by testing some basic and promising methods on PlEWi, a corpus of annotated spelling extracted from Polish Wikipedia. These modules may be further combined with appropriate solutions for error detection and context awareness. Following our results, combining edit distance with cosine distance of semantic vectors may be suggested for interpretable systems, while an LSTM, particularly enhanced by ELMo embeddings, seems to offer the best raw performance.

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