哈兰大学

In this study, the gamma and X-ray radiation attenuation properties of B4C-TiB2 reference ceramics and those reinforced with 1, 2, and 3 vol% graphene nanoplatelets (GNP) were systematically investigated. The composites were fabricated via Spark Plasma Sintering (SPS), enabling rapid densification and controlled microstructural evolution. B4C is known for its strong thermal neutron absorption due to its high 10B content. In addition, it contributes to gamma radiation attenuation through photon absorption and scattering interactions. The incorporation of TiB2 and GNPs into B4C enhances the composite density thereby increasing the photon interaction probability and improving the overall gamma shielding performance. Radiation attenuation measurements of the composites were conducted using 0.356 MeV (133Ba), 0.662 MeV (137Cs), and 1.173 MeV (60Co) sources, and diagnostic X-ray sources (50-110 kVp). Gamma and X-ray attenuation coefficients were independently calculated through MCNP6.2 Monte Carlo simulations to validate the experimental results. The close agreement between simulated and measured values demonstrates the reliability of the computational methodology and its consistency with established theoretical models of photon interaction cross sections. This consistency further supports the applicability of the approach for accurate evaluation and comparative analysis of photon attenuation performance in composite materials. In this study, key photon interaction parameters including the half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Zeff), and effective electron density (Neff) were computed. The results indicate that these parameters are significantly dependent on both the photon energy and the chemical composition of the examined composites. Both MCNP and experimental results show that the B4C-TiB2-GNP composites have linear attenuation coefficients (μ) ranging from 0.1468 to 0.2498 cm−1, with the sample with 1 vol% GNP (BT1G) exhibits the highest performance, reaching 0.2498 cm−1 for 133Ba. The results reveal that among all investigated samples, the BT1G composite exhibits the highest shielding efficiency in radiation conditions. GNP-reinforced B4C-TiB2 composites, may serve as a potential alternative to reduce the use of lead in gamma radiation protection.

The frequency and severity of floods and droughts have increased due to climate change, along with mismanagement, and increasing demand for water resources due to population growth. Due to this increasing demand, dependence on groundwater resources has been needed unprecedentedly. In addition, overuse and unsustainable irrigation have severely stressed groundwater, which is a limited resource. This study has been used multi-criteria decision-making methods to determine the spatio-temporal variation of groundwater potential zones for ensuring effective groundwater management and security. Geographic Information Systems (GIS) and Remote Sensing (RS) technologies are used to integrate 10 thematic layers, i.e., precipitation, soil, geology, elevation, lineament density, slope, drainage density, land use/land cover (LULC), topographic wetness index (TWI), and topographic roughness index (TRI). The groundwater potential areas, with a high spatial resolution of 10 m, were delineated using the Analytic Hierarchy Process (AHP) and Fuzzy Analytic Hierarchy Process (Fuzzy-AHP) in the study area of the Harran Plain, Türkiye. The integrity of the mapped potential zones was authenticated by well measurements and application of the Receiver Operating Characteristic (ROC) analysis, which yielded an Area Under Curve (AUC) value of 72.7

PurposeThis study investigates the impact of transformational school leadership on organizational change, emphasizing the mediating roles of instructional strategy self-efficacy and professional learning while also examining the direct effect of AI anxiety on organizational change. Design/methodology/approachA theoretical model is developed and tested using structural equation modeling based on data collected from 1,000 teachers across 40 schools in 20 provinces within Türkiye's NUTS-1: 12 regions. FindingsThe results reveal that teachers' perceptions of transformational school leadership positively influence instructional strategy self-efficacy, professional learning, and organizational change. Additionally, instructional strategy self-efficacy, professional learning, and AI anxiety are positively linked to organizational change. The mediation analysis highlights the significant role of instructional strategy self-efficacy and professional learning in explaining the relationship between transformational school leadership and organizational change. Originality/valueThis study contributes to the literature on leadership and organizational change by demonstrating the mechanisms through which transformational leadership fosters instructional strategy self-efficacy, professional learning, and adaptation to organizational change. It also extends research on AI anxiety and its influence on educational settings.

The study sheds light on the subtle interactions among financial development, foreign direct investment (FDI), and the quality of regulatory frameworks, with particular reference to their deep influence on renewable energy use and carbon emissions across 22 developed countries from 2002-2021. The results show an interesting tendency: Financial development and FDI will reduce reliance on renewable energy, whereas a significant increase in GDP per capita will increase reliance. Secondly, carbon emissions have a negative association with the adoption of renewable energy and financial development, though both reduce environmental quality; there is a positive relation between real gross domestic product (GDP) and energy depletion in terms of these toxic emissions. The significant role of regulatory quality as a moderator in this process is particularly striking. There is a direct correlation between financial stability and more robust regulation, resulting in reduced financial liquidity available for investing in renewable projects and restricting the free flow of clean FDI. Crucially, the paper argues that when combined with strong regulation, FDI is more likely to contribute to reductions in emissions, while FYGD, nevertheless regulated at a high level of quality, should raise emissions. Winding up, the result indicates that neither financial depth nor institutional quality, in isolation, is sufficient to deliver significant environmental improvement. Thus, it is urgent to adopt sound green finance policies and to formulate focused regulatory systems that integrate financial development and foreign direct investment with a broader sustainability agenda.

Four novel bioactive boron containing compounds (BCCs) were prepared by the reactions of quercetin and various boronic acids using a Dean-Stark technique to remove the H2O formed as a result of the chemical reaction. The antiepileptic properties of the bioactive BCCs also were investigated under suitable conditions. For this aim, the effect of the BCCs on the enzyme activities of carbonic anhydrase I and II isoenzymes (hCA I and hCA II) were evaluated spectrophotometrically. The bioactive BCCs have been investigated for their potential anticancer properties against PC-3, Du-145, and HEK-293 T cell lines utilizing the WST-1 assay method. Notably, the IC50 values of both boron compounds against the healthy control HEK-293 T cells were significantly higher compared to those observed in cancer cells. Lastly, bioactive boron containing compounds were examined through Gaussian calculations employing the B3LYP, HF, and M062X methods on the 6–31 + + g(d,p) basis set. Computational molecular docking was performed on specific proteins and ADME/T calculations were conducted to analyze the effects and interactions of these compounds at human metabolism.