Effect of acid concentration and time of sulphate process on synthesizing the titanium dioxide from synthetic rutile waste

A fast and easy method for preparing the titanium dioxide (TiO2), using a caustic hydrothermal decomposition conditions followed with sulphate process using sulfuric acid (H2SO4), is presented. Synthetic rutile waste as a starting raw material going through these two simple processes then the effects of acid concentration and time of sulphate process were studied. The chemical composition of the product will be characterized using Electron Dispersive (EDX) and the micrographs were analyzed using a Field Emission Scanning Electron Microscope (FESEM). This study shows that a titanium dioxide (TiO2) was successfully synthesized after treated with medium acid concentration, 1M to 3M and short treatment time, 3h to 5h sulphate process

Inverted classroom improves pre-university students understanding on basic topic of physics: the preliminary study

This paper discusses the effectiveness of the inverted classroom implemented in a pre-university physics classroom on topics of classical mechanics. Inverted classroom moves from traditional lectures to providing students with pre-recorded lectures and other materials such as videos, online quizzes and online exercises to foster independent learning. In this study, the classroom was divided into two groups: a control group and experimental group intervened with the inverted classroom; in evaluating the efficiency of the intervention, at the end of the module, both groups were tested using tests that are similar. The findings show that there was a significant difference between control group and experimental group on their pre-test and post-test score. It implies the potential use of this approach in other basic topics of pre-university physics classroomPeer Reviewe

Photocatalytic Degradation of Diclofenac by Nitrogen-Doped Carbon Quantum Dot-Graphitic Carbon Nitride (CNQD)

In this study nitrogen-doped carbon quantum dots/graphitic carbon nitride nanosheet (CNQD) composites with different contents of nitrogen-doped carbon quantum dots (NCQDs; 2, 4, 6, and 8 wt%) were synthesized. The morphological, physicochemical, and photoelectrochemical properties were investigated using complementary methods such as scanning electron microscopy (SEM), powder X-ray diffraction (pXRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), UV/Vis spectroscopy in diffuse reflectance (DRS), photoluminescence (PL), nitrogen physisorption (BET), photocurrent response, and electrochemical impedance spectroscopy (EIS). The photocatalytic activity of the synthesized materials was assessed during diclofenac (DCF) degradation in an aqueous solution under visible light irradiation. As a result, improved photocatalytic efficiency in DCF degradation was observed for all the CNQD composites compared with bulk graphitic carbon nitride (bCN) and nanosheet g-C₃N₄ (CNS). The fastest DCF degradation was observed for the 6 wt% NCQD on the surface of CNS (CNQD-6), which removed 62% of DCF in 3 h, with an associated k value of 5.41 × 10⁻³ min⁻¹. The performance test results confirmed the contribution of NCQDs to enhancing photocatalytic activity, leading to an improvement factor of 1.24 over bCN. The morphology of the CNS and the synergistic interaction between NCQDs and CNS were essential elements for enhancing photocatalytic activity. The photoelectrochemical data and photoluminescence analyses showed the efficient migration of photoexcited electrons from NCQDs to the CNS. The reduced charge recombination rates in CNQD photocatalysts might be due to the synergistic interaction between NCQDs and CNS and the unique up-conversion photoluminescence properties of NCQDs. Further investigations revealed that the photogenerated superoxide radicals (•O2⁻) predominated in the degradation of DCF, and this photocatalyst had good reusability and toxicity reduction abilities. This work provides insight into the effects of NCQDs on the CNS surface to enhance its potential to remove emerging organic pollutants from water and wastewater

Effectiveness of PBL-STEM module in physics on students’ interest: A preliminary finding of implementation amongst students in rural area of Sabah, Malaysia

Due to declining number of students enrolled in Science, Technology, Engineering and Mathematics education (STEM) subjects, the Ministry of Education has introduced STEM packages option for Form 4 students starting January 2020. Nevertheless, it is important to cultivate the learning interest towards STEM subjects starting from the lower form. In this study, an integrated problem-based learning Biology module called BOTANIstNJA was implemented to Form 1 and 2 of a secondary school in a rural area to gauge their interest in learning STEM subject. Total of 79 students participated in this case study related to plants, simple plant specimen activity and early career exposure as a Botanist. Three perspectives: teaching, learning, and communications skills were evaluated through questionnaires and analysed by means of frequency distribution. All students expressed “strongly agree” at 78.5%, 57.0%, and 51.9%, respectively. This result suggests the effectiveness of the integrated problem-based learning module to stimulate students’ interest and shall be continued to encourage them in taking the STEM package

Experimental analysis of titanium dioxide synthesis from synthetic rutile waste using a moderate acid concentration and temperature

The present study is to clarify the present influences of acid concentration and temperature of caustic hydrothermal method on extracting the titanium dioxide (TiO2) from synthetic rutile waste. In this experimental work, the caustic hydrothermal method comprises two processes: a decomposition and the sulphate process. The extracted titanium is characterized by using a electron dispersive X-ray spectroscopy to specify its chemical composition, field emission scanning electron microscope to determine the morphology and particle size, and lastly it is the X-ray diffraction to analyse the crystallinity of extracted titanium. In this study, we found that both acid concentration and temperature affected the TiO2 growth while the calcination process could improve the crystallinity of extracted titanium

Effect of acid concentration and time on synthesizing the titanium dioxide from synthetic rutile waste

A fast and easy method for preparing the titanium dioxide (TiO2), using a caustic hydrothermal decomposition conditions followed with sulphate process using sulfuric acid (H2SO4) are presented. The effects of acid concentration and treatment time of sulphate process to the TiO2 growth were focused in this research. The chemical composition of the product will be characterized using Electron Dispersive (EDX), the morphology and growth of titanium were analysed using a Field Emission Scanning Electron Microscope (FESEM) and the crystallinity of sample were analysed by X-Ray Diffraction (XRD). From this research work, we found that the caustic hydrothermal decomposition method followed with sulphate process has been proven to extract a titanium nanocrystals with the average mean size < 100nm after treated with medium acid concentration and short treatment time

Inverted classroom improves pre-university studens understanding on basic topic of Physics:: The preliminary study

This paper discusses the effectiveness of the inverted classroom implemented in a pre-university physics classroom on topics of classical mechanics. Inverted classroom moves from traditional lectures to providing students with pre-recorded lectures and other materials such as videos, online quizzes and online exercises to foster independent learning. In this study, the classroom was divided into two groups: a control group and experimental group intervened with the inverted classroom; in evaluating the efficiency of the intervention, at the end of the module, both groups were tested using tests that are similar. The findings show that there was a significant difference between control group and experimental group on their pre-test and post-test score. It implies the potential use of this approach in other basic topics of pre-university physics classroo