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Room-temperature ammonia sensing performance of 1D ZnO/Si nanorods: Influence of zinc precursors and yttrium doping levels
No full textAmmonia (NH3) is considered a promising alternative for sustainable energy storage and transport due to its carbon-free nature. However, at elevated concentrations, NH3 can cause respiratory irritation, eye damage, and environmental harm by contaminating water sources. As a flammable and toxic gas, its detection and control are critical for both human health and ecological safety. In this study, one-dimensional pure and yttrium (Y)-doped ZnO nanorods (1 %, 3 %, 5 %, and 7 %) were synthesized on silicon substrates via the hydrothermal method using two different chemical precursors: acetate and nitrate. These nanostructures were employed as NH3 gas sensors operating at room temperature. X-ray diffraction analysis confirmed the formation of hexagonal wurtzite structures with a preferred c-axis orientation, as indicated by dominant (002) peaks. SEM images revealed that Y doping modified the nanorods' aspect ratios, which directly impacted gas sensing performance. Higher aspect ratios enhanced the surface-to-volume ratio and lowered resistance, resulting in improved sensing behavior. Among all sensors, the 3 % Y-doped ZnO nanorods synthesized with acetate precursor exhibited the best performance, showing a maximum sensitivity of 101 % to 50 ppm NH3. This sensor also showed fast dynamics with a response time of 20 s and recovery time of 41 s. Sensitivity was found to increase proportionally with gas concentration. Furthermore, additional characterizations, including detection limit, baseline current, selectivity, long-term stability, and wettability, were carried out to comprehensively evaluate sensor performance. Finally, the role of Y doping in enhancing gas sensing was elucidated, highlighting its dual structural and electronic contributions to the sensing mechanism
From global standards to local realities: Understanding the Granada Statements in pharmacy practice research
No full textIntroduction: The Granada Statements were developed to improve the quality and visibility of pharmacy practice research by encouraging consistency in reporting. However, little is known about how these guidelines are interpreted in low- and middle-income countries (LMICs), where professional roles and services may differ. Examining these perspectives can highlight both barriers and opportunities for wider uptake. Aim: This study explored how clinical and social pharmacy researchers perceive the Granada Statements, focusing on the challenges, enablers, and strategies that could enhance their application in resource-limited contexts. Method: A qualitative design was adopted, using focus group discussions with researchers in Türkiye. Data were thematically analyzed through collaborative coding and interpretation. Special attention was given to the Statements’ key areas, including terminology, journal selection, perceptions of relevance, and proposed improvements. Results: Participants regarded the Statements as a useful framework for clarifying expectations, promoting consistency, and stimulating dialogue about research quality. Barriers included difficulties applying standardized terminology in evolving service contexts, challenges in translating technical terms, undervaluation of LMIC research, financial constraints in open access publishing, and discouraging peer review experiences. Suggested enablers included templates, illustrative examples, modular adoption, culturally sensitive glossaries, and training with editors. A global classification framework for benchmarking pharmacy practice was also proposed. Conclusion: This study shows that the Granada Statements have the potential to act not only as reporting guidance but also as a framework for more intentional, theory-driven, and globally relevant pharmacy practice research. Flexibility, contextual sensitivity, and institutional support are key to achieving this vision
Investigating the Reaction Rate Expressions of Methanol and Sodium Borohydride via Cyclic Voltammetry
No full textA Numerical Investigation Into the Effects of Equivalence Ratio and Exhaust Gas Recirculation on Performance and Operating Range in High Compression HCCI Engines
No full textAbstract This study investigates the performance of a high compression ratio engine converted to homogeneous charge compression ignition (HCCI) operation. A total of 24 case studies were conducted with φ = 0.22–0.29 and exhaust gas recirculation (EGR) = 0–30%. Numerical analyses were conducted using three-dimensional computational fluid dynamics simulations in avlfire software. The results indicated that increasing the equivalence ratio improved combustion efficiency, with the indicated mean effective pressure (IMEP) increasing from 3.74 bar at φ = 0.23 to 4.92 bar at φ = 0.28, while thermal efficiency improved from 46.13% to 49.88%. However, the sharp increase in the maximum pressure rise rate (MPRR) at φ = 0.28 suggested that engine operation approached the knock limit, showing the tradeoff with knock. Furthermore, increasing the EGR rate led to a reduction in combustion temperatures, with the maximum temperature dropping from 1779 K at 0% EGR to 1588 K at 20% EGR. While IMEP decreased from 4.92 bar at 0% EGR to 3.98 bar at 20% EGR, CO and HC increased due to low temperatures. On the other hand, NOx emissions, which are inherently low in HCCI combustion due to low temperatures, were further reduced with increasing EGR rates, because of both the temperature decrease and the reduced oxygen availability. Higher EGR levels also raised the risk of misfire, especially at lower equivalence ratios, narrowing the engine's stable range. These findings highlight the potential of HCCI engines to improve both environmental sustainability and energy efficiency, requiring precise control to avoid knock and misfire.</jats:p
Bayesian inference based high cycle fatigue modeling of forged 7050-T7452 aluminum alloy: Effects of surface treatments and defects
No full textIn aerospace applications, surface treatments are widely employed to enhance the corrosion resistance of aluminum alloys as part of sustainability-oriented strategies; however, such treatments and surface defects degrade fatigue performance and compromise long-term structural integrity. This study focuses on the long-life fatigue behavior of forged aerospace grade 7050-T7452 aluminum alloy under various surface conditions, including chromic acid anodizing, sulfuric hard anodizing, and artificially introduced surface defects (corroded pits and scratches). Fatigue performance was characterized through Bayesian-based S-N curve modeling, enabling probabilistic assessment of fatigue life. Fractography was employed to identify crack initiation sites and assess the role of microstructural and geometrical discontinuities. Sulfuric hard anodizing exhibited the most pronounced reduction in fatigue performance up to 66.23%, primarily attributed to increased oxide layer thickness and tendency to promote multiple crack initiation. In contrast, chromic acid anodizing exhibited negligible fatigue degradation in the endurance limit region. At 5x107 cycles, fatigue knockdown factors were quantified as 2.81%, 66.23%, 55.58%, and 61.77% for chromic acid anodizing, sulfuric hard anodizing, corroded pit, and scratch groups, respectively. Surface defects significantly reduced fatigue strength by promoting multiple crack nucleation and accelerating crack propagation. Defect-tolerant approach was assessed using a modified Kitagawa-Takahashi diagram based on root area parameter and El Haddad model
Post-disaster permanent housing and life satisfaction in Van, Turkey: Impacts of housing satisfaction, socioeconomic and demographic factors
No full textThis study investigates the factors influencing life satisfaction among residents of post-disaster permanent housing in Van, Turkey, following the 2011 earthquake. Data were collected through a survey of 382 households across five districts, examining socioeconomic factors, housing satisfaction, and their impact on overall life satisfaction. Multiple regression analysis revealed that income, satisfactions from housing attributes, neighborhood characteristics and social activities, and demographic factors significantly influence residents' life satisfaction. Households facing fewer difficulties meeting housing expenditures reported higher levels of life satisfaction. The study highlights that both objective housing attributes, such as housing quality, and subjective perceptions, such as neighborhood satisfaction and sense of community, significantly influence residents' overall life satisfaction. These findings, consistent with existing research, underscore the importance of addressing socioeconomic disparities and improving housing quality to enhance residents' well-being. The study emphasizes the need to incorporate residents' needs and preferences into post-disaster permanent housing policies to promote successful resettlement and ensure the long-term well-being of disaster-affected communities
Toxic Effects of Lead Nitrate and Cadmium Chloride on Rat Lung Tissue and The Protective Role of Sesamol
No full textAnalysis of neutronic and hydrogen production potential of a triso-coated CANDU nuclear-fueled hybrid reactor with thermochemical cycles
No full textIn this study, firstly, time-dependent neutronic analyses of a hybrid reactor with a 5 MW/m2 wall load and FLiNaK coolant using TRISO-coated CANDU spent fuel were performed. Neutronic analyses were performed using the XSDRNPM/SCALE nuclear code program. The effects of TRISO coated CANDU spent nuclear fuel on tritium breeding ratio (TBR), total fission rate (Σf), energy multiplication factor (M) and Burn up (BU) were investigated. Over the 48-month time period, the TBR value increased from approximately 1.082 at the beginning to approximately 1.14 at the end of 48th month. M, burn up and fissile fuel rates have also increased continuously during these 48-months. While the initial values of M was approximately 1.97, this value was obtained as 2.351 at the end of period. Also, the BU value was performed as 53.85 GWd/tM at the end of 48-month study period. Secondly, the potential of hydrogen production in the hybrid reactor integrated hydrogen production facility which has the magnesium chloride (Mg-Cl), vanadium chloride (V-Cl) and copper chloride (Cu-Cl) thermochemical cycles were investigated. As a result, the highest amount of the hydrogen production with Mg-Cl was obtained as 11.94 kg/s followed by the Cu-Cl as 5.62 kg/s depends on energy multiplication factor at the end of operation.</p
Efficient k Value Computation for Enhanced Fuzzy Ridge Regression
No full textSelecting an optimal bias parameter k is a critical challenge in Ridge regression, particularly in the context of fuzzy datasets affected by multicollinearity. Traditional approaches, such as K-fold cross-validation, are commonly used for this purpose but can be computationally demanding and may not always provide precise estimates. This study systematically investigates the efficiency of 77 distinct formulas for determining k within the framework of fuzzy Ridge regression, an area that has not been previously explored. Unlike previous studies, this work is the first to evaluate such a large set of candidate formulas across 54 simulated scenarios and three real-world datasets, providing an extensive empirical examination of their effectiveness. Additionally, it introduces an analysis of how different α-level sequences influence the selection process and impact the results, demonstrating that formula-driven methods can achieve comparable accuracy to K-fold cross-validation with significantly reduced computational effort. These findings highlight the advantages of using predefined formulas for bias parameter selection, offering a practical and efficient alternative to traditional techniques. Furthermore, this study demonstrates the robustness of α-level-based fuzzy Ridge regression and its effectiveness in handling fuzzy data with multicollinearity, contributing valuable insights into improving the efficiency and applicability of fuzzy regression models in various fields