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Cleaner hydrogen production by microwaves: Experimental investigation and comparative assessment
No full textSustainable development goals of the United Nations require cleaner energy solutions and carbon-free fuels. Hydrogen, in this regard, appears to be a unique candidate for all, and its production in a cleaner manner is critically important, which is the prime focus in the present paper. This study focuses on the newly designed experimental investigations into microwave-driven water dissociation for cleaner hydrogen production, specifically exploring the effect of various tungsten-based electrode materials and steam inlet conditions on hydrogen production. The evaluation is conducted in two main sections, assessing hydrogen production at the water dissociation level and the overall system. Some of the key observations include a positive correlation between steam inlet temperature and hydrogen production for all electrode materials, with lanthanated tungsten demonstrating superior performance. When only the water dissociation is considered, lanthanated tungsten electrodes exhibit the most favorable energy consumption, showcasing the minimum energy requirement for hydrogen production. Incorporating the overall energy and exergy efficiencies, the lanthanated tungsten emerges as the top performer, followed by ceriated tungsten, attributed to their superior arc stability. The energy requirement per kg of hydrogen varies from 51.98 kWh/kg to 56.66 kWh/kg for varying steam inlet temperatures from 104 degrees C to 120 degrees C. The highest energy and exergy efficiencies are recorded to be 64.1 % and 62.3 %, respectively, for lanthanated tungsten electrodes at 120 degrees C steam inlet temperature. When all energy inputs (steam generation, preheating, condenser pump, and microwave generator) are considered, the overall energy and exergy efficiencies are found to be 35.1 % and 34.2 %, respectively. The energy needed for 1 kg of hydrogen production is recorded to be 94.87 kWh/kg. Consequently, the lanthanated tungsten electrode stands out as a superior performer, offering valuable implications for advancing microwave hydrogen production technologies
Novel manganese tricarbonyl complexes with benzimidazole ligands: Investigation of CO-releasing, antioxidant, antibacterial, zeta potential, theoretical, and electrochemical properties
No full textManganese(I) carbonyl complexes bearing various bioactivities are evaluated for their CO-releasing properties. Benzimidazole type molecules which are well known for their therapeutic applications are frequently used as ligands in coordination complexes. In this study, three novel manganese(I) complexes coordinated by 2-substituted benzimidazoles were synthesized bearing CO-releasing properties. The synthesized complexes were characterized by various spectroscopic methods such as IR, 1H NMR, 13C NMR, LC-MS, SEM and EDX, whereas electrochemical characterization was done by cyclic voltammetry. CO-releasing properties of the complexes were analyzed by Myoglobin Assay. The antioxidant activities of the complexes were evaluated in terms of their DPPH and SOD radical scavenging capacities as well as their chelation potentials with Fe2+ depending on CO release at two different concentrations. Antibacterial activity tests were performed in order to test the complexes for their potential for various therapeutic purposes. Antimicrobial activities were tested in vitro against six human pathogenic bacteria and two fungi. The stability of complexes was checked via zetasizer measurements such as particle size and zeta potentials of the complexes at different pH values. Additionally, molecular docking was performed against the crystal structures of DNA Gyrase of E. coli (PDB ID: 1kzn), and Human peroxiredoxin 5 (PDB ID: 1hd2)
Mindfulness Matters: Untangling Entrapment and Mental Well-Being in Married Couples
No full textIndividual experiences can influence the mental health of married couples. The objective of the present study is to investigate the mediating role of mindfulness in marriage between entrapment and mental well-being by examining the relationships between actors and partners. The actor-partner interdependence mediation model was employed to apply a dyadic approach to the data collected from 423 (N = 846) married couples for this purpose. The mean age of the women was 35.80 (SD = 9.57), while the mean age of the men was 39.0 (SD = 10.46). The results indicated that the relationships between entrapment, mindfulness, and mental well-being were substantial for both genders. It was discovered that the entrapment experienced by each of the couples predicted their own well-being through the mindfulness of the other in marriage in the context of partner effects. In other words, women's entrapment predicted their mental well-being, which in turn predicted men's mindfulness in marriage. Similarly, the mindfulness of women in marriage predicts the mental well-being of men. Consequently, it is anticipated that the well-being of both spouses will be enhanced if the mindfulness levels of individuals experiencing entrapment are high
A Detailed Framework for Modeling Three-Phase Power System Components in Phase Coordinates at Harmonic Frequencies
No full textThis paper presents a comprehensiveframework for modeling three-phase power system components in phase coordinatesunder harmonic frequency conditions. The increasing presence of nonlinear loadsand harmonic components in power systems necessitates accurate modeling ofsystem elements. Within this framework, transformers, transmission lines, series-parallelcomponents, as well as passive loads, are modeled in detail with respect toharmonic frequencies. Transformer models incorporate considerations such asconnection groups, phase shifts, and leakage reactance’s, while nonlineareffects like core saturation are not included. Transmission lines arerepresented by harmonic impedance and shunt admittance matrices, accommodatingboth symmetrical and asymmetrical configurations. Additionally, series andparallel elements and passive loads are modeled using frequency-dependentmatrix formulations. The proposed modeling approach provides a robustfoundation for harmonic load flow analysis and power quality simulations,contributing both theoretical rigor and practical applicability.</p
Modadan Derinliğe: Eğitimde Yapay Zekâ ve Öğretmen Gelişimini 'Normalleşme' Kavramıyla Okumak
No full textCharacteristic Roots, Eigenvalues and Eigenvectors of a Certain Type of 4×4 Dual Tridiagonal Matrices
No full textA Comprehensive Analysis of Fractal Geometry in the Interior Architecture of the Astana Grand Mosque
No full textIn recent years, there has been a significant academic interest in the relationship between fractals and social networks. Both systems demonstrate complex, self-organizing patterns, making them a subject of fascination. Fractals, characterized by self-repeating geometric shapes, and social networks, which depict intricate connections among individuals or entities, share structural dynamics that are worth exploring. This research aims to investigate these parallels, with a particular emphasis on the implications of fractal patterns in various disciplines like architecture and sociology. A focal point of the study is the application of fractal geometry in the interior design of a mosque that was nominated for a prestigious Guinness award. The research examines how fractals are utilized in this case, to create visually captivating designs and to symbolize deeper spiritual and social connections. By analysing this example, the research contributes to the broader understanding of the interdisciplinary nature of fractals and their potential impact across diverse fields such as physics, architecture, and social theory. Additionally, a fictional element is incorporated to further illustrate these concepts
