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Nanotechnology finds its application almost in every field of science and technology. At the same time, it also helps to find the solution to various environment-related problems, especially water contamination. Nanomaterials have many advantages over conventional materials, such as high surface area, both polar and non-polar chemistries, controlled and size-tunable, easier biodegradation, which made them ideal candidates for water and environmental remediation as well. Herein, applications of non-carbon nanomaterials, such as layered double hydroxides, iron oxide magnetite nanoparticles, nano-polymer composites, metal oxide nanomaterials and nanomembranes/fibers in heavy metal contaminated water and environmental remediation are reviewed. These non-carbon nanomaterials, due to their tunable unique chemistry and small size have greater potentials for water and environmental remediation applications.

In our current work, we have established a novel approach in the synthesis of a new adsorbent by using choline chloride and urea (DES)/orthophosphoric acid (H3PO4) as our activating agent and palm kernel shell (PKS) as our precursor. The resulting activated carbon (DES/H3PO4-6002:3) was used to adsorb Pb(II) from aqueous solution. Characterization of DES-H3PO4-6002:3 by nitrogen adsorption/desorption isotherm measurements, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) demonstrated good micropores structure and high surface area that makes DES/H3PO4-600 2:3 a suitable alternative for liquid phase adsorption. The fundamental batch experiment of DES/H3PO4-600 2:3 was investigated by different parameters (such as concentration, pH, temperature and absorbent dose). The results obtained indicated that Langmuir model and pseudo-second-order equation best fit the data, indicating that the adsorption was controlled by chemical reaction and monolayer uptake. In addition, the fabrication of DES/H3PO4 AC exhibits good potential for Pb(II) ions uptake, including its high adsorption capacity (97.1 mg/g) and good recyclability. The future potential of this works lies in the identification of alternatives to environmental benign synthesis AC and reuse of Pb(II) ion–laden biosorbent after heavy metal uptake.

Intending to enhance educational outcomes for indigenous students, who have long been undervalued in many present educational systems, there is an increasing variety of educational interventions in mathematics learning. This is in line with two of the Sustainable Development Goals (SDGs), which are quality education and reduced inequalities, especially among indigenous students. Nevertheless, no research on indigenous students, locally known as Orang Asli, has been performed in Malaysia. Hence, the purpose of this research is to systematically review empirical studies from various countries that documented interventions to help indigenous students in their acquisition of mathematics from 2007 to 2022. This review included a total of 25 studies. Indigenous students from elementary to high school participated in these programs, which took place in both formal and informal settings. The majority of interventions are used in formal settings and elementary schools. The two key characteristics of the interventions were their scientific inquiry practice and cultural relevance. Regarding indigenous students’ cognitive, psychomotor, and affective domains, all interventions indicated successful outcomes. This information will benefit not only Malaysian indigenous mathematics teachers and researchers but also academics from all over the world in order to help improve indigenous students’ mathematics learning.

This study focuses on reviewing information from several articles published in educational and social sciences journals worldwide to document the trend of geometric thinking studies in the Indonesian context. The current study shows that the number of publications on geometric thinking has increased in the last four years. The studies conducted in Indonesia and for Indonesian students used a systematic review guided by PRISMA to examine a hundred articles indexed by Scopus, Google Scholar, and Science and Technology Index (SINTA) between 2011 and 2021. Van Hiele’s Geometric Thinking Test, developed by Usiskin, is extensively used when examining geometric thinking levels in the intervention. In addition, descriptive analysis and a t-test are also employed. The result shows that the most common type of geometric thinking experimental research is quasi-experimental design, with the qualitative approach found to be the most used. Therefore, educators should increase the quantity of qualitative and quantitative studies from various nations about geometric thinking. Furthermore, it is also essential to examine the correlation between student performance in geometry and the teacher’s level of geometric thinking. Finally, combining the van Hiele Geometry test with interviews is strongly advised to provide comprehensive and in-depth data for examining geometric thinking.

Total hip arthroplasty (THA) is most likely one of the most successful surgical procedures in medicine. It is estimated that three in four patients live beyond the first post-operative year, so appropriate surgery is needed to alleviate an otherwise long-standing suboptimal functional level. However, research has shown that during a complete THA procedure, a solid hip implant inserted in the femur can damage the main arterial supply of the cortex and damage the medullary space, leading to cortical bone resorption. Therefore, this study aimed to design a porous hip implant with a focus on providing more space for better osteointegration, improving the medullary revascularisation and blood circulation of patients. Based on a review of the literature, a lightweight implant design was developed by applying topology optimisation and changing the materials of the implant. Gyroid and Voronoi lattice structures and a solid hip implant (as a control) were designed. In total, three designs of hip implants were constructed by using SolidWorks and nTopology software version 2.31. Point loads were applied at the x, y and z-axis to imitate the stance phase condition. The forces represented were x = 320 N, y = −170 N, and z = −2850 N. The materials that were used in this study were titanium alloys. All of the designs were then simulated by using Marc Mentat software version 2020 (MSC Software Corporation, Munich, Germany) via a finite element method. Analysis of the study on topology optimisation demonstrated that the Voronoi lattice structure yielded the lowest von Mises stress and displacement values, at 313.96 MPa and 1.50 mm, respectively, with titanium alloys as the materials. The results also indicate that porous hip implants have the potential to be implemented for hip implant replacement, whereby the mechanical integrity is still preserved. This result will not only help orthopaedic surgeons to justify the design choices, but could also provide new insights for future studies in biomechanics.

Heavy metal pollution, such as lead, can cause contamination of water resources and harm human life. Many techniques have been explored and utilized to overcome this problem, with adsorption technology being the most common strategies for water treatment. In this study, carbon nanofibers, polyacrylonitrile (PAN)/sago lignin (SL) carbon nanofibers (PAN/SL CNF) and PAN/SL activated carbon nanofibers (PAN/SL ACNF), with a diameter approximately 300 nm, were produced by electrospinning blends of polyacrylonitrile and sago lignin followed by thermal and acid treatments and used as adsorbents for the removal of Pb(II) ions from aqueous solutions. The incorporation of biodegradable and renewable SL in PAN/SL blends fibers produces the CNF with a smaller diameter than PAN only but preserves the structure of CNF. The adsorption of Pb(II) ions on PAN/SL ACNF was three times higher than that of PAN/SL CNF. The enhanced removal was due to the nitric acid treatment that resulted in the formation of surface oxygenated functional groups that promoted the Pb(II) ions adsorption. The best-suited adsorption conditions that gave the highest percentage removal of 67%, with an adsorption capacity of 524 mg/g, were 40 mg of adsorbent dosage, 125 ppm of Pb(II) solution, pH 5, and a contact time of 240 min. The adsorption data fitted the Langmuir isotherm and the pseudo-second-order kinetic models, indicating that the adsorption is a monolayer, and is governed by the availability of the adsorption sites. With the adsorption capacity of 588 mg/g, determined via the Langmuir isotherm model, the study demonstrated the potential of PAN/SL ACNFs as the adsorbent for the removal of Pb(II) ions from aqueous solution.

Three-dimensional printing is widely used in many fields, including engineering, architecture and even medical purposes. The focus of the study is to obtain the ideal weight-to-performance ratio for making a 3D-printed part. The end products of the 3D-printed part are hugely affected by not only the material but also the printing parameters. The printing parameters to be highlighted for this study are the infill density, wall perimeter and layer height, which are the commonly adjusted parameters in 3D printing. The study will be divided into two parts, the simulation analysis and the experimental analysis, to confirm both results toward the trend of Young’s modulus for the material. It will then be analyzed and discussed toward any differences between the two results. The results showed that increasing the value of all three parameters will increase the tensile elasticity of the part.

Neat cellulose acetate (CA) and CA/polysulfone (PSf) blend ultrafiltration membranes in the presence of polyvinylpyrrolidone as a pore former were prepared via a phase inversion technique. The prepared membranes were characterized by Fourier transform infrared, scanning electron microscopy, mechanical strength, water content, porosity, permeate flux and heavy metals (Pb2+, Cd2+, Zn2+ and Ni2+) rejection to comprehend the impact of polymer blend composition and additive on the properties of the modified membranes. The water flux expanded by increasing of PSf content in the polymer composition. CA/PSf (60/40) had the highest flux among prepared membranes. Prepared blend membranes were able to remove heavy metals from water in the following order: Pb2+ > Cd2+ > Zn2+ > Ni2+. The CA/PSf (80/20) blend membrane had great performance among prepared membranes due to the high heavy metals removal and permeate flux.

As school leaders, novice principals faced some challenges within the first years of their leadership journey. This mixed-methods study explores the initial challenges faced by novice principals while leading their schools. At the same time, their countering strategies in handling the initial challenges are also being explored. A total of 168 novice principals responded to all items within a questionnaire on their initial challenges and their useful strategies to overcome the challenges. In addition, 11 novice principals were interviewed for in-depth information on their challenges and possible strategies in overcoming them. Findings revealed that dealing with a previous principal’s legacy and heavy workloads were major challenges faced by novice principals. In terms of their countering strategies, novice principals employed various approaches such as organizing an initial meeting with teachers, getting parents involved in school activities, and sharing leadership practice.

Calix[4]arene/polyurethane (C4PU) has been synthesized and characterized as an alternative adsorbent for the adsorption of methylene blue (MB) and malachite green (MG) dyes from the aqueous solution. C4PU was synthesized by reacting p -tert-butyl calix[4]arene with hexamethylene diisocyanate (HMDI) as the cross-linking agent. Different polymer ratios were synthesized, and C4PU-4 shows better adsorption than other ratios. The polymer was characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) analysis, and point of zero charges (pH PZC ). The isotherms and kinetics of the adsorption of MB and MG were studied under a range of experimental conditions, including pH, adsorbent dosage, initial dye concentration, and contact time. The adsorption was determined by the adsorption percentage of MB and MG dyes from the solution. The Langmuir isotherm model best describes the adsorption process for both dyes, and it follows a pseudo-second-order kinetic model, with the maximum adsorption capacity ( q max ) of MB and MG, respectively, was found to be 1.991 mg·g −1 and 2.240 mg·g −1 . Graphical Abstract