Liners are provided under engineering landfill sites to block the downflow of leachates and their noxious components to minimize pollution in the underlying aquifers or neighboring water bodies. Compacted clays are widely employed as suitable materials for constructing landfill liners because of their low hydraulic conductivity, balanced swelling potentials, and appropriate compressive strength. However, the quality has to be improved if the locally available soil does not meet the minimum standards for constructing liner materials. Including bentonite dosage with local soil can show better stability and strengthened cohesion bonds between molecules. This paper aims at a recent study on specific geotechnical properties of bentonite amended local Khulna clay soil intended to be used as a liner material. Bentonite in varying proportions (e.g., 5%, 10%, 15%, and 20%) was mixed with local soil, and specific tests (e.g., compaction tests, consistency tests, hydraulic conductivity tests, fre.....

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Urbanization significantly accelerates the replacement of natural land-use and land-cover (LULC) classes, which can raise the temperature and diminish thermal comfort zone (TCZ), potentially negatively affecting the environment and human health. This study assesses and predicts the impacts of LULC change on directional shrinkage of the TCZ in Kuwait, using Landsat images and cellular automata (CA) and artificial neural networks (ANN) algorithms from 1991 to 2031. The analysis revealed a rapid urban expansion (40%) in south-east (SE), north-east (NE), and north-west (NW) directions and shrinkage of TCZ (25% area with a very uncomfortable thermal condition) in NNW and SW directions, from 1991 to 2021. The predicted scenario showed an increase in urban areas from 44% (2021) to 47% (2026) and 52% (2031). In contrast, very uncomfortable TCZ (35% in 2026 and 40% in 2031) was found concentrated around urban areas and bare land toward NNE and NNW directions. The study proposes effective and su.....

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In the present study, various polyvinylidene fluoride (PVDF)-based membranes were successfully fabricated via non-solvent induced phase separation (NIPS) method utilising different carbon-based materials as additive. The incorporation of reduced graphene oxide (rGO), multi-walled carbon nanotubes (MWCNTs) and GO-MWCNTs hybrid along with titanium dioxide (TiO2) definitely affect the fabricated membrane's morphology, hydrophilicity, porosity, filtration performance and antifouling properties. Based on dead-end filtration measurement, rGO-based PVDF/TiO2 membrane presented excellent pure water flux (2446.887 L/m2h) with membrane permeability of 1143.850 L/m2hMPa compared to other membranes. Furthermore, the inclusion of rGO and TiO2 also resulted in the highest methylene blue (MB) dye rejection rate (?92%) compared to MWCNTs (62.22%) and GO-MWCNTs (86.69%). It was believed that steric hindrance effect played a major role in enhancing dye rejection performance of PVDF@rGO/TiO2 membrane. In.....

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The Federal University of Technology at Akure (FUTA) in Nigeria is experiencing ongoing development that is leading to the replacement of agricultural and forestry land cover types. This study aimed to assess and predict changes in land use/land cover (LULC) types and their impact on crop characteristics in 17 plots of FUTA from 1991 to 2031. Crop characteristics were evaluated using the normalized difference vegetation index (NDVI), normalized difference water index (NDWI), normalized difference moisture index (NDMI), vegetation condition index (VCI), watershed delineation, and spectral characteristics using Landsat imageries. The land change modeler in TerraSet software was used to predict future LULC scenarios. Results showed an increase in built-up areas (15%) and bare land areas (14%), but a reduction of 19% in light vegetation cover from 1991 to 2021. The predicted LULC map illustrated a decrease in light vegetation area (11%) and an increase in built-up area (19%) from 1991 to 2.....

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Radical changes across almost all areas, including education, due to the COVID-19 outbreak. One of the rapid transformations is digital learning, also known as e-learning. Digital learning transformation has been taking place for more than a decade. However, little comprehensive analysis of digital transformation in teaching in public schools. To the best of the authors knowledge, no comprehensive analysis incorporates external and internal barriers and examines the prominent theories to study successful e-learning integration among teachers. The aim of this study was to provide a thematic and theoretical understanding of digital learning transformation among teachers in public schools. The data for the study was acquired from the Scopus databases. The study employed content and comparative analysis and advocated a grounded theory approach to inductively analyze and criticize the theme construction for answering two research questions. Based on a set of criteria to determine whether ea.....

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This study was carried out to uncover the pedagogical gaps by characterizing the teaching practices of chemistry within a teacher education institution and subsequently, identifying the prevalent, non-prevalent and unobserved teaching practices. Accordingly, this implementation study employed the classroom observation method. The one-semester implementation of 11 chemistry lessons of a university lecturer was observed using a psychometrically-validated observation checklist comprises 50 items or indicators that measure six principles (dimensions). The use of the observation checklist entails checking whether each indicator is observed or otherwise during classroom observations. With a frequency of more than 25% to be considered prevalent, the findings indicate that the lecturer prevalently maintained a scaffolding of instructional alignment (62.5%), offered quality learning environments, resources, and technology (57.1%), and promoted positive beliefs, attitudes, and behavioral pattern.....

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Exposure of synthetic dye, such as methylene blue (MB), in water bodies led to a serious threat to living things because they are toxic and non-degradable. Amongst the introduced dye removal methods, membrane separation process can be considered a powerful technique for treating dye contamination. However, this method commonly suffered from drawbacks, such as short membrane lifetime, low permeability and selectivity. To overcome these issues, graphene oxide (GO) and titanium dioxide (TiO2) were used as additives to fabricate polyethersulfone (PES)- and polyvinylidene fluoride (PVDF)-based hybrid membranes via non-solvent-induced phase separation method. Prior to membrane fabrication, GO was synthesised via electrochemical exfoliation method assisted by customised triple-tail surfactant. The potential of PES- and PVDF-based hybrid membranes for wastewater treatment has been discussed widely. However, direct comparison between these two polymeric membranes is not critically discussed for.....

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An improved fractional-order sliding mode control (FOSMC) for PMSM is presented in this study to set the unavoidable parameters and to improve permanent magnet synchronous motors (PMSMs) drive performance, such as current and speed tracking accuracy. To determine the optimal parameters of the FOSMC for control speed in a PMSM drive, a neural network algorithm with reinforcement learning (RLNNA) is proposed. The FOSMC parameters are set by the ANN algorithm and then adapted through reinforcement learning to enhance the results. The proposed controller using RLNNA based on fractional-order sliding mode control (RLNNA-FOSMC) can drive the motor speed to achieve the referred value in a finite period of time, leading to faster convergence and improved tracking accuracy. For a fair comparison and evaluation, the proposed RLNNA-FOSMC is compared with conventional FOSMC by applying the integral of time multiplied absolute error as an objective function. The most commonly used objective functio.....

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In a previous study, we made some new discoveries regarding the use of holograms, particularly as a substitute for classroom instructors. The appropriate hologram tutor character is an important topic to study, considering that the character design as a hologram can significantly influence student learning emotions. In addition, the character design of the hologram tutor is believed to influence the students learning experience (LX). Since hologram tutors can have a positive impact on learning sessions, their use should be maintained. However, one of the issues that will hamper the use of hologram tutors in the future is the size of the platform, which is big and challenging to handle. In fact, hologram technology can also utilize the Talking-Head application. This 3D Hologram Talking-head is more manageable due to its smaller size. However, since the 3D Hologram Talking-head only displays the characters head, the effect of using it on students learning emotions remained unclear. There.....

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Plants have always been a common source of medicaments, either in the form of traditional preparations or as pure active principles. Polyalthia belong to the Annonaceae family and are a type of evergreen trees distributed across many tropical and subtropical regions. Polyalthia stenopetala is locally used to treat rheumatic fever and diarrhea. Herein, we report the phytochemical composition and acetylcholinesterase (AChE) inhibitory activity of Polyalthia stenopetala. Fractionation and purification of the stem bark extract of P. stenopetala led to isolation and identification of laurotetanine (1), N-methyllaurotetanine (2), reticuline (3), liriodenine (4), yangambin (5), syringaresinol (6), vanillic acid (7), 4-hydroxybenzoic acid (8), cinnamic acid (9), and syringic acid (10). Structures of these ten compounds were elucidated using different spectral analyses and their comparison with previously reported data. All isolated compounds were found to inhibit AChE (inhibition of 40.2 to 80.....

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