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Text-mining and bibliometric analyses for proton exchange membrane electrolyzers
No full textThe dependence on technology has increased, along with the development and change in living standards, which has led to increased energy demand and emissions. Therefore, researchers have focused on green hydrogen production to meet the energy demand and reduce emissions. The proton exchange membrane (PEM) electrolysis is one of the most promising methods for producing green hydrogen, attracting increasing attention from researchers in academia and industry. This study focuses on the bibliometric and text-mining analyses of PEM electrolyzers to identify general trends and the current state of the literature, thereby guiding researchers in future work. In this regard, a dataset was first generated using keywords and abstracts extracted from the Scopus webpage. Then, bibliometric and text-mining analyses were conducted on the dataset using R Studio and Python modeling. Our results demonstrate that research on PEM electrolyzers has increased significantly over the past few years, along with an expansion in the diversity of research topics within the field. Most studies in the literature have focused on material design and the integration of PEM electrolyzers with alternative energy systems. Furthermore, techno-economic analysis, life cycle assessment, multi-objective optimization, and machine learning are identified as emerging research areas. Overall, this work provides a comprehensive overview of the current state of PEM electrolyzer research and identifies future directions emphasizing advanced materials development, renewable energy integration, and sustainable energy management strategies
Room-temperature electron-selective passivating contact with titanium–peroxo complexes for high-efficiency silicon solar cells
No full textThe increasing demand for high-performance and cost-effective solar cells is a driving factor in the development of new nanomaterials or compounds compatible with low-cost, low-temperature fabrication routes. Titanium oxide (TiOx), an inexpensive earth-abundant material, is among the most extensively investigated candidates for electron-selective layer implementation in silicon solar cells. In this context, we investigate the effect of hydrogen peroxide (H2O2) modification of a solution-processed TiOx precursor on the resulting film and device properties. Through various characterization studies, the formation of titanium–peroxo (Ti–OO) complexes upon H2O2 modification is consolidated, and the subsequent structural, optical, and electrochemical properties are examined. Owing to H2O2 modification, an outstanding implied open-circuit voltage (iVoc) of 713 mV and a low contact resistivity (ρc) of 1.96 mΩ cm2 are simultaneously achieved. At the device level, a maximum power conversion efficiency (PCE) of 21.9% is measured for cells incorporating a modified-TiOx/LiFx/Al rear contact, representing a gain of 1.8% compared to control cells with a LiFx/Al rear contact. Notably, this performance is attained using dopant-free standalone TiOx produced at room temperature, without any annealing steps throughout the fabrication process. Stability assessments of unencapsulated devices reveal the superior thermal stability of the modified devices under practical conditions. Moreover, the devices' behavior under illumination is simulated using Solar Cell Capacitance Simulator (SCAPS) software to elucidate the role of modified-TiOx properties in the enhanced photovoltaic (PV) performance metrics. The accomplishments outlined in this study open new avenues for advancing high-efficiency crystalline silicon (c-Si) solar cells through a simplified fabrication process
Comprehensive energy modeling and optimization of hybrid PV-Wind systems for Ankara, Türkiye and Fujairah, UAE
No full textThis study develops a robust modelling and optimization framework for a hybrid photovoltaic (PV) and wind energy systems through a comparative techno-economic and environmental analysis of Ankara, T & uuml;rkiye, and Fujairah, UAE, two climatically distinct regions with strong renewable energy potential. Utilizing a multi-tool approach integrating Python-based simulations, HOMER Pro analysis, and PVWatts benchmarking, the study evaluates energy generation, seasonal load matching, economic feasibility, and carbon mitigation. Key metrics, including levelized cost of electricity (LCOE), capacity factors, and system losses, were analysed to identify optimal system configurations under site-specific constraints. Fujairah demonstrated stronger renewable energy potential overall, with both higher solar irradiance and superior wind resources. It achieved approximately 8,902 MWh of annual solar energy (HOMER Pro) with LCOE values ranging from 0.085 to 0.12 USD/kWh. However, system design in Ankara strategically relied more heavily on wind energy due to its relatively lower solar resource, leading to a wind capacity factor of 47.8% and an annual wind energy production of 7,595.83 MWh (HOMER Pro), despite higher associated LCOE values (0.15 to 0.29 USD/kWh). Modelling comparisons revealed that Python-based outputs, 8,126.76 MWh for Ankara and 9,017.15 MWh for Fujairah, tended to overestimate energy production by not fully incorporating real-world derating factors, unlike HOMER Pro's more conservative estimates. Environmental analysis confirmed notable carbon mitigation benefits, with Fujairah achieving 7,729 metric tons of CO2 offset annually, slightly surpassing Ankara due to a higher grid emission factor. This work fills a critical gap in the literature by providing a high-resolution, cross-regional evaluation of hybrid renewable systems. It demonstrates the importance of localized design, real-world constraints, and multi-platform validation to guide efficient renewable energy deployment, providing a reproducible and scalable methodological framework for hybrid energy studies worldwide
Hydroxyapatite and polycaprolactone composites as potential biomaterials in biomedical applications
No full textHydroxyapatite and polycaprolactone (HA/PCL) composites show significant potential in biomedical applications, especially in bone tissue engineering. HA's high hardness and brittleness, the low stiffness and flexible mechanical structure of PCL, and the microstructural properties such as porosity and crystallinity can be controlled in composite fabrication and designed to suit the desired biomedical applications. Integrating ion doping into the HA structure or surface modifications to PCL involves designing biocompatible supporting composites. This modification can enhance cellular reactions such as increased cell proliferation, migration, and differentiation, as mentioned in in vitro studies. To provide a comprehensive understanding of the benefits of the produced composites, chemical synthesis of HA and PCL, mechanical, structural, and biological properties are examined, and the application areas are specified. This review shows the promising role of HA/PCL composites in advancing biomedical applications and developing effective treatment methods. The aim is to provide a comprehensive overview of the role of HA/PCL composites in biomedical fields such as hard and soft tissue and drug delivery, as well as the path ahead for increasing clinical studies. This study compiles the current potential research from HA and PCL synthesis to HA/PCL fabrication and laboratory and clinical studies
Local p + Poly-Si Passivating Contacts Realized by Direct FlexTrail Printing of Boron Ink and Selective Alkaline Etching for High Efficiency TOPCon Based Solar Cells
No full textIn this work, we demonstrate the formation of local boron-doped, SiOₓ/p + poly-Si structures using wet chemical etching by direct printing of boron-ink. FlexTrail printing uses a very hollow (orders of μm for diameter) glass capillary tube filled with boron ink for printing onto silicon substrate. This process represents a mask-free approach for the formation of local TOPCon structures, enabling high-efficiency tunnel oxide passivating contact (TOPCon) solar cells. The factors influencing etch-back selectivity between intrinsic and boron-doped poly-Si were thoroughly investigated. It was determined that pre-treatment with diluted HF (1 wt%) prior to poly-Si removal in a KOH solution is the most critical step to achieve optimal etch selectivity. This treatment effectively removes the native oxide on intrinsic poly-Si while preserving the boron silicate glass (BSG) layer on p + poly-Si, facilitating the selective removal of intrinsic poly-Si and the formation of p + TOPCon structures. Line widths ranging from 24.0 to 100.5 μm on planar surfaces and 40.0–86.0 μm on textured surfaces were achieved. FlexTrail printing allows for significantly lower (and higher) feature sizes, but its fine-line potential was not fully exploited here due to alignment challenges during post-processing. Test structures with a line grid of local TOPCon structures exhibited a maximum open-circuit voltage (iVOC of 720 mV and a lowest saturation current density (JOSE) of ~90–120 fA/cm2. The developed local p + poly-Si will be integrated into high-efficiency TOPCon solar cells, where p + poly-Si will be strategically placed under the metal contact, in the near future
Measuring the semantic priming effect across many languages
No full textSemantic priming has been studied for nearly 50 years across various experimental manipulations and theoretical frameworks. Although previous studies provide insight into the cognitive underpinnings of semantic representations, they have suffered from small sample sizes and a lack of linguistic and cultural diversity. In this Registered Report, we measured the size and the variability of the semantic priming effect across 19 languages (n = 25,163 participants analysed) by creating the largest available database of semantic priming values using an adaptive sampling procedure. We found evidence for semantic priming in terms of differences in response latencies between related word-pair conditions and unrelated word-pair conditions. Model comparisons showed that the inclusion of a random intercept for language improved model fit, providing support for variability in semantic priming across languages. This study highlights the robustness and variability of semantic priming across languages and provides a rich, linguistically diverse dataset for further analysis. The Stage 1 protocol for this Registered Report was accepted in principle on 15 July 2022. The protocol, as accepted by the journal, can be found at https://osf.io/u5bp6 (registration) or https://osf.io/q4fjy (preprint version 6, 31 May 2022)
Women's Civil Society Organizations in Turkey: Reflections of Europeanisation and De-Europeanisation along the EU Journey
No full textThis book focuses on the de-Europeanisation process that Turkey is undergoing through an examination of women's civil society organizations. Considering the lively women's movement in the country and its diversity, it questions whether a transformation has occurred in the way that women's CSOs perceive the European Union and make use of the financial and strategic support offered by the EU as part of the latter's recognition of the importance of CSOs in candidate and new member states. with attention to the ways in which the contributions of the EU enabled such organizations to intensify and widen their activities, as well as their lobbying and networking prospects, the authors examine the effects on these of Turkey's fluctuating relations with the EU and the parallel de-Europeanisation process that has marked the last decade.</p
Seismic Enhancement of Masonry-Infilled Substandard Reinforced Concrete Frames Using Lightweight Steel Exoskeleton
No full textA significant portion of existing reinforced concrete (RC) structures in seismically active regions was constructed prior to the adoption of modern seismic design standards, leaving them highly susceptible to earthquake-induced damage. The vulnerabilities of these structures, often exacerbated by material degradation, have been starkly revealed in recent seismic events. This study addresses the urgent need for effective retrofitting solutions by evaluating the seismic performance of deficient masonry-infilled RC frames retrofitted with a novel lightweight steel exoskeleton system—Resisto 5.9 Tube—designed to enhance structural resilience. Three full-scale RC frame specimens, replicating typical deficiencies of older construction practices, were subjected to quasi-static cyclic loading up to near-collapse conditions, with interstory drifts ranging from 0.05% to 2.50%. The test series included: a bare frame (BF), an infilled frame with unreinforced hollow clay masonry units (IF), and a retrofitted infilled frame (RIF) incorporating the steel exoskeleton. Results reveal that masonry infill substantially increases lateral load capacity—by factors of 2.42 (IF) and 3.59 (RIF) compared to BF. However, IF exhibited a brittle failure mode, with significantly reduced displacement capacity. In contrast, the exoskeleton-enhanced RIF demonstrated a 147% increase in load capacity relative to IF, extended peak force occurrence to 0.70% drift, and achieved improved cyclic stability. While initial stiffness remained comparable between IF and RIF (within 4% difference), energy dissipation in RIF at 1.50% drift was threefold that of IF. Further, the exoskeleton system markedly improved the performance of the infill wall, extending the defined limit and damage states at ultimate by up to 150% and 344%, respectively. These enhancements facilitated sustained infill–frame interaction under large drifts, a behavior often neglected in conventional seismic design. The findings position the Resisto 5.9 Tube as a cost-effective and scalable retrofitting solution, offering a paradigm shift in how infill contributions are considered in seismic response assessments. This work establishes a foundation for advanced analytical modeling and practical implementation in earthquake-prone regions
From comfort zone to growth zone: Experiential projects as catalysts for creativity in pre-service teachers
No full textThis study aimed to analyze the creative experiences of early childhood pre-service teachers enrolled in a semester-long course designed to enhance their creative potential through experiential projects. Using a qualitative research design, this study explored the subjective experiences of 16 pre-service teachers, aged 21 to 23-years-old, who participated in a 14-week course focused on integrating creativity into early childhood education. Data were collected through weekly reflections, project reports, and multimedia documentation, capturing each pre-service teacher's creative journey. The findings revealed four key themes which characterized the pre-service teachers' creative experiences: (1) learning a new skill, (2) expressing creativity and experiencing a sense of accomplishment, (3) overcoming challenges related to fear and insecurity, and (4) achieving personal fulfillment and professional growth. These open-ended projects fostered an environment where the pre-service teachers could take risks, embrace failure, and reflect on their development, building essential skills such as problem-solving, creative confidence, and resilience. This approach equipped pre-service teachers with the skills and mindset necessary to foster creativity in their future classrooms, supporting both their personal and professional growth
