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The objective of this research is to develop and characterize polyethylene composites with randomly and partially oriented hybrid filler (HF) based on multiwalled carbon nanotubes (MWCNTs) decorated with gamma iron (III) oxide (γ‐Fe2O3) nanoparticles (Fe2O3/MWCNTs). The structure of Fe2O3/MWCNTs hybrid is determined by X‐ray diffraction (XRD), Raman spectroscopy, and microscopy techniques (scanning electron microscopy–energy‐dispersive X‐ray spectroscopy, transmission electron microscopy). A low‐density polyethylene (LDPE) matrix is filled with 5 and 10 vol% HF. The effect of external magnetic field on the distribution of Fe2O3/MWCNTs in LDPE composites comparing to filler distribution without magnetic field is studied. The XRD and differential scanning calorimetry results confirm an increasing trend in the degree of crystallinity of LDPE matrix with increasing HF content and as an additional result of magnetic field application. The presence of more ordered Fe2O3/MWCNT particles in the matrix has enhanced the nucleation effect for LDPE crystallization process in composites under magnetic field. The effect of magnetic treatment on thermal, electrical, and thermoresistive properties of HF‐LDPE composites is studied. The highest thermoresistive response (723%) and fastest recovery are detected for the HF‐LDPE composite with 10 vol% magnetically oriented filler with the perspective to be applied as a critical temperature resistor. [ABSTRACT FROM AUTHOR]

This work describes impact of concentration of BiFeO3 submicrometric particles on piezoelectric performance and structural characteristics of 0–3 polymer composites with a polystyrene matrix. Bismuth ferrite particles are fabricated using reverse co‐precipitation method, followed by ultrasonic dispersion in a solvent to break up agglomerates formed during sintering, resulting in particles with a size of ≈200 nm. It is found that concentrations higher than 10 wt% BiFeO3 lead to a disturbance in natural organization of polystyrene. The hindered organization of side‐groups by submicrometric filler, occurring during solvent evaporation, strongly affects the mechanical properties of the finalcomposite, significantly increasing Young's modulus and tensile strength, but decreasing elongation. Such behavior is detected and described for the firsttime in literature. Piezoelectric examinations show that the thermal depolarization of nanogenerators has a different impact depending on the amountof piezoelectric phase. The study reveals that a voltage of over 4.8 V is generated when dynamic air pressure is applied at 11.54 bar for the composite containing only 2.5 wt% BiFeO3. For composites with 10% weight fraction or lower, decrease in generated voltage after thermal depolarization is about 24%, while for higher weight fractions (15 and 20 wt%) the decrease is around 35%. [ABSTRACT FROM AUTHOR]

Growing demand for electric energy in newly developed electronic systems causes increasing interest in research on piezoelectric nanogenerators (PENGs). Design and fabrication of such devices is challenging, considering cost of materials used in their construction. This is the main reason why intensive research has begun on 0‐3 composites with piezoelectric properties. One of the most promising constituent materials for composites fabrication are polymers, due to their low cost and easy processing. Herein, we present fabricated wearable PENG with good impact and vibration energy conversion properties. Correlation between matrix stiffness and piezoelectric properties of 0‐3 type composite is proposed. It was found that composite with 10 wt.% of BiFeO3 particles exhibits power output density for vibrations, finger tapping, and air stream pressure P = 11.12 nW cm−3, P = 4.83 μW cm−3, and P = 769.2 μW cm−3, respectively. Decrease in stiffness of epoxy matrix results at least in two‐times lower power output density for this same PENG. The obtained results demonstrate that the fabricated BFO/epoxy composites show the wide applicability and potential to be integrated with other functional devices, for example, as a part of wearable devices in smart shoes. [ABSTRACT FROM AUTHOR]

Background: The year 2023 is a special time for Polish-Türkiye diplomatic relations. It is the 100th anniversary of the proclamation of the Republic of Türkiye and the 100th anniversary of its recognition by Poland. One area of this public and economic diplomacy is the debates on the different dimensions of the experiences, practices or frameworks of mutual cooperation between Poland and Türkiye, organised by the Foundation for Research on Türkiye in cooperation with the Regional Centre for International Debate in Krakow. The article is a synthesis of considerations undertaken in the area of Polish- Türkiye economic cooperation, with a particular focus on technology and innovation. Research objectives: The article aims to describe the potential pathways for enhancing mutual economic and political relations between Poland and Türkiye. Methods: The paper is based on content analysis of the debate on Polish-Türkiye cooperation in the area of innovation and technology, the potential of both countries in this respect, and the possibilities for its development. The debate took place in March 2023, and the authors were one of the panellists. The findings enrich statistical data coming from the Polish Central Statistical Office. Results: The paper highlights the strong economic ties between Poland and Türkiye, underscoring their joint endeavours across various industries. Both governments have ambitious plans to significantly boost their trade balance by 2023, with a particular emphasis on sectors like energy, mining, IT, automotive, and textiles, showcasing a mutual commitment to growth and partnership. Conclusions: Establishing and developing economic cooperation between Poland and Türkiye can benefit both countries. The mechanisms and initiatives mentioned above can help to increase trade and investment flows, create new business opportunities, and promote mutual learning and innovation. [ABSTRACT FROM AUTHOR]

More than a year after the Russian aggression against Ukraine, a little can already be said about Turkey's attitude and the consequences of the conflict for Ankara. Turkey is balancing between Moscow and Kiev, trying to gain ground as a mediator, but also looking after its interests, especially economic ones. The text aims to analyse Turkish-Russian and Turkish-Ukrainian relations, especially since the outbreak of the war, and to answer the question of what the possible consequences of the Russian-Ukrainian war are for Turkey, whether it will be the big winner or rather the big loser of the situation. [ABSTRACT FROM AUTHOR]