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In this study, basalt and/or beech wood fibers were treated with vinyltrimethoxysilane or compatibilized by maleic anhydride‐ grafted polypropylene (MAPP) to produce hybrid polylactic acid (PLA) biocomposites. Twin‐screw extruder was used to produce biocomposites, following by a hot press to form samples. Physical and mechanical properties of composites that were produced from both treated and untreated fibers were compared. Chemical, morphological, and thermal analysis of biocomposites were analyzed with TGA, FTIR and SEM, respectively. The results showed that silane treated basalt/wood fiber reinforced PLA (PBWS) and silane treated basalt reinforced PLA (PBS) have significantly better flexural strength than neat PLA. Besides, basalt reinforced bio‐composites except PBW3 and PBWM variations have significantly superior impact strength than neat PLA. Utilization of compatibilizers also reduced thickness swelling and water uptake features of biocomposites. All the above experimental data showed that the utilization of silane compatibilizer has better impact on properties than MAPP for such wood/basalt hybrid composite. Highlights: Hybrid biocomposites with wood and basalt fibers by using coupling agents were prepared for the first time.Hybridization of organic and inorganic fibers gave promising results.Silane and maleic anhydride compatibilization improves physical properties.Vinyltrimethoxy silane grafted basalt fiber improves flexural strength significantly.Silanization of wood or basalt fibers enhances significantly the impact strength. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate attitudes towards physical activity and their levels of life satisfaction of high school students. The sampling group of the study that was descriptive in scanning model was composed of 412 students, chosen by suitable sampling method, studying at high schools' levels in Artova district of Tokat province. "Personal Information Form", "Cognitive Behavioural Physical Activity Scale" and "Life Satisfaction Scale" were applied to the students. Descriptive statistics such as percentage, frequency, arithmetic mean and standard deviation, and Kolmogorov Smirnov test to examine the distribution of data were performed in the analysis of the data. And in order to test the hypothesises of the study parametric tests such as independent sample t-test and oneway anova were performed. In addition, Pearson Correlation test was performed to test the relationship between dependent variables such as students' attitude towards physical activity and life satisfaction level. According to the results of the analysis, independent variables such as gender, sports, place of life and class level bring about a significant difference on students' attitude towards physical activity and life satisfaction level. Moreover, the findings of the study show that there is a low level, positive and meaningful relationship between life satisfaction level and physical activity attitude. As a result of the study, it was found that the students' attitudes towards physical activity and their life satisfaction levels were affected by various variables and there was a meaningful relationship between these two dependent variables. [ABSTRACT FROM AUTHOR]

Recently, piezoelectric nanogenerators have received great interest as they can convert waste mechanical and radiative energy to electricity and can be used in self‐energy generating systems and sensor technologies. In this study, electrospun poly(vinylidene fluoride) (PVDF) nanofiber‐based piezoelectric nanogenerators with reduced graphene oxide (rGO), polyaniline (PANI), and PANI‐functionalized rGO (rGOPANI) have been developed. Two different types of nanofiber mats were produced: First, rGO‐ and rGOPANI‐doped PVDF nanofiber mats and second, rGO, PANI and rGOPANI‐spray‐coated PVDF nanofiber mats that have worked as nanogenerators' electrodes. Then, characterizations of samples were performed in terms of piezoelectricity, Fourier transform infrared (FTIR) spectrophotometric, X‐ray diffractions (XRD), and scanning electron microscopy analyses. FTIR and XRD results confirmed that piezoelectric β‐crystalline phase of PVDF occurred after the electrospinning process. Besides, maximum output voltages were obtained as 7.84 and 10.60 V for rGO‐doped PVDF and rGOPANI‐coated PVDF nanofiber mats, respectively. As a result, the doped nanofibers were found to be more successful due to the higher device accuracy in sensor technologies compared with spray‐coated samples. However, spray‐coating method proved to be more suitable technique for the production of nanogenerators on an industrial scale in terms of fast and large‐scale applicability. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48517. [ABSTRACT FROM AUTHOR]