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During the COVID-19 pandemic, educational mobile games may play a significant role to facilitate students’ learning. Several studies have indicated that these games using mobile phones may improve students’ learning motivation and effectiveness when they are equipped with appropriate learning strategies. However, investigating the impact of learning strategies in students’ utilization of educational mobile games has received little scholarly attention during the COVID-19 pandemic. Hence, this research proposed two learning games scenarios to fill this gap. In the first scenario, students were offered an educational mobile game with a learning strategy called ‘scaffolding strategy’; while in the second scenario, the same game was offered without the strategy. To achieve this objective, an experimental design with a research model was developed to examine the role of scaffolding learning strategy in students’ use of educational mobile games. In this experimental study, 43 students from two classes participated in the two learning scenarios. The results indicate that educational mobile gaming with the scaffolding learning strategy significantly influenced students’ utilization of the mobile game. In addition, the adoption of the learning strategy significantly affected students’ perceived enjoyment, perceived usefulness, perceived ease of use, and behavioural intention to use, compared with the same game without the learning strategy. The results also indicate that the introduction of the scaffolding learning strategy into the educational mobile game will increase students’ learning effectiveness and motivation.

Globally, the empowerment of women is a critical and challenging issue. In considering the problem, the researchers sought to investigate Women’s Empowerment (WE) in the context of Saudi Arabia. In this study the researchers applied quantitative methods and collected the cross-sectional data through a questionnaire based on a random sampling technique. The study utilized 314 useable samples to conclude the investigation. Using path analysis through Analysis of Moment Structures (AMOS) version 26.0, the study underlines a positive and significant effect of Economic Empowerment (EE) and Social Empowerment (SE) on WE. On the other hand, Political Empowerment (PE) has a negative effect on WE. Moreover, Self-efficacy (SFY) and Family Support (FS) also positively and significantly affect WE. Regarding the mediating effects, SFY mediates the positive relationship of EE and SE with WE. On the contrary, SFY did not develop a positive relationship between PE and WE. Finally, FS plays a crucial mediating role in developing the association between EE, SE, PE and WE among Saudi Arabian women. This study’s findings support policymakers and planners in developing policies and strategies to boost WE significantly. Finally, through the empirical confirmation between EE, SE, PE, SFY, FS and WE in Saudi Arabia, a Middle East country, this study’s findings add further enrichment to the depth of the literature.

Alkali activated concretes have emerged as a prospective alternative to conventional concrete wherein diverse waste materials have been converted as valuable spin-offs. This paper presents a wide experimental study on the sustainability of employing waste sawdust as a fine/coarse aggregate replacement incorporating fly ash (FA) and granulated blast furnace slag (GBFS) to make high-performance cement-free lightweight concretes. Waste sawdust was replaced with aggregate at 0, 25, 50, 75, and 100 vol% incorporating alkali binder, including 70% FA and 30% GBFS. The blend was activated using a low sodium hydroxide concentration (2 M). The acoustic, thermal, and predicted engineering properties of concretes were evaluated, and the life cycle of various mixtures were calculated to investigate the sustainability of concrete. Besides this, by using the available experimental test database, an optimized Artificial Neural Network (ANN) was developed to estimate the mechanical properties of the designed alkali-activated mortar mixes depending on each sawdust volume percentage. Based on the findings, it was found that the sound absorption and reduction in thermal conductivity were enhanced with increasing sawdust contents. The compressive strengths of the specimens were found to be influenced by the sawdust content and the strength dropped from 65 to 48 MPa with the corresponding increase in the sawdust levels from 0% up to 100%. The results also showed that the emissions of carbon dioxide, energy utilization, and outlay tended to drop with an increase in the amount of sawdust and show more the lightweight concrete to be more sustainable for construction applications.

The growing population and increasing urbanization have led to a surge in domestic wastewater generation, posing significant challenges for effective and sustainable treatment. The present study demonstrates a novel and sustainable approach for the onsite treatment of domestic wastewater using an integrated settler-based biofilm reactor (ISBR) with efficient biogas generation. The ISBR provides an optimized environment for the growth of biofilm, facilitating the removal of organic pollutants and pathogens. Moreover, the ISBR enables the recovery of a valuable resource in the form of biogas, thus enhancing the overall utility of the treatment process. The performance of the ISBR was comprehensively evaluated at laboratory scale through treating the actual domestic wastewater generated from the hostel of Manipal University Jaipur. The ISBR system was operated under an ambient environment at a hydraulic retention time (HRT) of 24 h. The results demonstrated remarkable efficiency in terms of chemical oxygen demand (COD), total suspended solids (TSS), and coliforms removal, with average removal efficiency being more than 90%. According to the COD mass balance analysis, 48.2% of the influent COD was recovered as bioenergy. The chromatogram revealed a high percentage of methane gas in the collected biogas sample. The field emission scanning electron microscope (FESEM) analysis of the accumulated sludge in the ISBR system depicted the morphology of methanogenic bacteria. Both the experimental and theoretical results confirmed the feasibility and sustainability of the ISBR system at the onsite level.

Cette étude examine les caractéristiques des profils de vitesse, de champ thermique et d'entropie pour l'écoulement de nanofluides hybrides traversant une feuille d'amidonnage avec un rayonnement thermique. Les nanotubes de carbone (SWCNT et MWCNT) sont utilisés comme nanoparticules avec flux de chaleur Cattaneo-Christov (CC). L'éthylène glycol est utilisé comme fluide de base dans ce cas. Pour obtenir une solution améliorée, l'écoulement de fluide sur les propriétés géométriques est conçu en utilisant des PDE hautement non linéaires, et les équations gouvernantes doivent être converties en systèmes d'équations non similaires sans dimension en utilisant le schéma de Keller-box bien connu et très efficace dans le logiciel de calcul Matlab. La faisabilité pratique de ces solutions est déterminée par la plage des paramètres de contrôle. La distribution de vitesse diminue à mesure que l'estimation des paramètres magnétiques augmente, cependant, le champ de température et la production d'entropie augmentent à mesure que la fluctuation des paramètres magnétiques diminue. Au fur et à mesure que le paramètre de glissement augmente, le champ de vitesse diminue. Le champ thermique est amélioré pour augmenter le paramètre de rayonnement, et le profil d'entropie est renforcé pour augmenter les valeurs des paramètres de Brinkman. Les résultats de cette recherche pourraient avoir un impact significatif sur les industries où le refroidissement et le chauffage locaux par jets d'impact sont nécessaires dans les appareils électroniques, les dissipateurs thermiques, les technologies de séchage, etc. À la connaissance des auteurs, il s'agit du premier effort visant à utiliser un nanofluide hybride pour analyser la formation d'entropie due au flux magnétohydrodynamique sur une feuille d'amidonnage. Este estudio examina las características de los perfiles de velocidad, campo térmico y entropía para el flujo híbrido de nanofluidos que pasa a través de una lámina de almidón con radiación térmica. Los nanotubos de carbono (SWCNT y MWCNT) se utilizan como nanopartículas con flujo de calor Cattaneo-Christov (CC). El etilenglicol se utiliza como fluido base en este caso. Para lograr una solución mejorada, el flujo de fluido sobre las propiedades geométricas se diseña utilizando PDE altamente no lineales, y las ecuaciones gobernantes deben convertirse en sistemas de ecuaciones no similares adimensionales utilizando el conocido esquema de Keller-box altamente eficiente en el software computacional MATLAB. La viabilidad práctica de estas soluciones está determinada por el rango de los parámetros de control. La distribución de velocidad se reduce a medida que aumenta la estimación del parámetro magnético, sin embargo, el campo de temperatura y la producción de entropía aumentan a medida que la fluctuación del parámetro magnético se aclara. A medida que aumenta el parámetro de deslizamiento, el campo de velocidad disminuye. El campo térmico se mejora para aumentar el parámetro de radiación, y el perfil de entropía se aumenta para aumentar los valores de los parámetros de Brinkman. Los hallazgos de esta investigación podrían tener un impacto significativo en las industrias donde se necesita refrigeración local y calefacción a través de chorros de choque en dispositivos electrónicos, disipadores de calor, tecnologías de secado, etc. Según el conocimiento de los autores, este es el primer esfuerzo para emplear un nanofluido híbrido para analizar la formación de entropía debido al flujo magnetohidrodinámico sobre una lámina de almidón. This study examines the characteristics of the velocity, thermal field and entropy profiles for hybrid nanofluid flow passing through a starching sheet with thermal radiation. The carbon nanotube (SWCNT and MWCNT) are used as a nanoparticles with Cattaneo-Christov (CC) heat flux. Ethylene glycol is utilized as a base fluid in this case. To achieve an improved solution, the fluid flow over the geometric properties is designed using highly non-linear PDEs, and the governing equations must be converted into dimensionless non-similar equation systems using the highly efficient well-known Keller-box scheme in computational software MATLAB. The practical feasibility of these solutions is determined by the range of the controlling parameters. The velocity distribution reduces as the magnetic parameter estimate increases, however, the temperature field and entropy production increase as the magnetic parameter fluctuation esclates. As the slip parameter is increased, the velocity field diminish. The thermal field is enhanced for rising the radiation parameter, and the entropy profile is boosted for increasing Brinkman parameter values. The findings of this research might have a significant impact on industries where local cooling and heating via impingement jets are needed in electronic devices, heat sinks, drying technologies, and so on. To the best of the authors' knowledge, this is the first effort to employ a hybrid nanofluid to analyze entropy formation due to magnetohydrodynamics flow over a starching sheet. تبحث هذه الدراسة في خصائص ملامح السرعة والحقل الحراري والانتروبيا لتدفق السوائل النانوية الهجينة التي تمر عبر ورقة النشا مع الإشعاع الحراري. يتم استخدام الأنبوب النانوي الكربوني (SWCNT و MWCNT) كجسيمات نانوية مع تدفق حراري Cattaneo - Christov (CC). يستخدم جلايكول الإيثيلين كسائل أساسي في هذه الحالة. لتحقيق حل محسّن، تم تصميم تدفق المائع عبر الخصائص الهندسية باستخدام PDEs غير خطية للغاية، ويجب تحويل المعادلات الحاكمة إلى أنظمة معادلات غير متشابهة بلا أبعاد باستخدام مخطط Keller - box المعروف عالي الكفاءة في البرنامج الحاسوبي MATLAB. يتم تحديد الجدوى العملية لهذه الحلول من خلال نطاق معلمات التحكم. ينخفض توزيع السرعة مع زيادة تقدير المعلمة المغناطيسية، ومع ذلك، يزداد مجال درجة الحرارة وإنتاج الإنتروبيا مع تذبذب المعلمة المغناطيسية. مع زيادة معامل الانزلاق، يتناقص مجال السرعة. يتم تعزيز المجال الحراري لرفع معلمة الإشعاع، ويتم تعزيز ملف تعريف الإنتروبيا لزيادة قيم معلمة برينكمان. قد يكون لنتائج هذا البحث تأثير كبير على الصناعات التي تحتاج إلى التبريد والتدفئة المحليين عبر نفاثات الاصطدام في الأجهزة الإلكترونية وأحواض الحرارة وتقنيات التجفيف وما إلى ذلك. على حد علم المؤلفين، هذا هو أول جهد لتوظيف مائع نانوي هجين لتحليل تكوين الإنتروبيا بسبب تدفق الديناميكا المائية المغناطيسية على ورقة النشا.

Abstract The impact of a twisted turbulator in a parabolic solar collector on the improvement of thermal–hydraulic performance (THP), as well as energy and exergy Efficiency of MgO-Cu/water hybrid nanofluid (HNF) is numerically evaluated. The main goal of this study is to use a twisted turbulator with pitch ratios (γ) of 1, 1.5, 2, and 2.5 for Reynolds numbers (Re) of 8000 to 32,000 and volume fractions (ϕ) of 1, 2, and 3% of MgO and Cu nanoparticles. Numerical simulation findings are reported in the form of graphs of average Nusselt number (Nuave), pressure drop (Δp), THP, energy Efficiency ( η c ) , and exergy Efficiency ( η ex ) . It can be concluded that Nuave and Δp depends on ϕ and Re and augments linearly with their values. Moreover, Nuave and Δp increases significantly by increasing the pitch ratio of the turbulator. The results revealed that the maximum values of augmentation of η c and η ex are respectively 23.79% and 21.15% by raising Re from 8000 to 32000. In a SC with a turbulator with γ = 2 and ϕ = 3%, η c is raised by 24.16% by increasing Re from 8000 to 32000; while, in the case of γ = 2.5 and ϕ = 3%, η c is enhanced by 18.2%.

Assessing the impacts of climate change and land use/land cover changes on water resources within a catchment is essential because it helps us understand how these dynamic factors affect the quantity, quality, and availability of freshwater. This knowledge is crucial for making informed decisions about water management, conservation, and adaptation strategies, especially in regions facing increasing environmental uncertainties and challenges to water resource sustainability. In Pakistan’s Kunhar River Basin (KRB), this investigation explores the potential effects of shifting land use/land cover (LULC), and climate on stream flows. The SWAT (Soil and Water Assessment Tool), a semi-distributed hydrological model, and the most recent Coupled Model Intercomparison Project phase 6 (CMIP6) dataset from multiple global climate models (GCMs) were used to evaluate these effects. The temperature and precipitation data were downscaled using the CMhyd software; for both shared socioeconomic pathways (SSP2 and SSP5), the top-performing GCM out of four was required to produce downscaled precipitation and temperature predictions while taking future land use characteristics into account. The output from the chosen GCM indicated that by the conclusion of the 21st century, relative to the reference period (1985–2014), the study area’s average monthly precipitation, highest temperature, and lowest temperature will be increasing. Precipitation is anticipated to increase between 2015 and 2100 by 20.5% and 29.1% according to the SSP2 and SSP5 scenarios, respectively. This study’s findings, which emphasize the need for project planners and managers taking into account the effects of climate and land cover changes in their management techniques, show that climate change can have a significant impact on the changing seasons of flows in the Kunhar River basin.

The synthesis of biodiesel from Jatropha curcas by transesterification is kinetically controlled. It depends on the molar ratio, reaction time, and temperature, as well as the catalyst nature and quantity. The aim of this study was to explore the transesterification of low-cost, inedible J. curcas seed oil utilizing both homogenous (potassium hydroxide; KOH) and heterogenous (calcium oxide; CaO) catalysis. In this effort, two steps were used. First, free fatty acids in J. curcas oil were reduced from 12.4 to less than 1 wt.% with sulfuric acid-catalyzed pretreatment. Transesterification subsequently converted the oil to biodiesel. The yield of fatty acid methyl esters was optimized by varying the reaction time, catalyst load, and methanol-to-oil molar ratio. A maximum yield of 96% was obtained from CaO nanoparticles at a reaction time of 5.5 h with 4 wt.% of the catalyst and an 18:1 methanol-to-oil molar ratio. The optimum conditions for KOH were a molar ratio of methanol to oil of 9:1, 5 wt.% of the catalyst, and a reaction time of 3.5 h, and this returned a yield of 92%. The fuel properties of the optimized biodiesel were within the limits specified in ASTM D6751, the American biodiesel standard. In addition, the 5% blends in petroleum diesel were within the ranges prescribed in ASTM D975, the American diesel fuel standard.