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GeoGebra is a dynamic geometric software developed for the support of mathematics teaching. The aim of this research was to study the effect of GeoGebra on mathematics achievement in relation to the linear equations and explore the perception of students towards the use of GeoGebra in teaching mathematics. Forty students were participating in this quasi-experimental study in which one group was assigned as experimental and another as control group. Data were collected by using self-constructed tools and analyzed by using percentage, mean, standard deviation and t-test as well as effect size was calculated. The result from the study revealed that the achievement of GeoGebra instructed students was significantly higher than the control group. Additionally, level of perceptions of experimental group students found to be high towards the use of GeoGebra. Hence teachers should use this software while they instruct graph of linear equations in their lessons and curriculum developers and textbook writers should incorporate such kind of activities into the curriculum and textbooks.

1,1‐Diethoxybutane is a high‐potential biofuel additive that enhances various fuel properties, which include cetane number, lubricity, biodegradability, and flash point. This work presents a kinetic and thermodynamic study on the acetalization reaction between butanal and ethanol in the presence of Amberlyst‐15 wet in a batch reactor. The experiments were conducted in the temperature range 313–333 K at atmospheric pressure with three different initial molar ratios of reactants and catalyst loadings. An optimal parameter setting to achieve maximum equilibrium conversion of butanal was derived from a parametric study with these three factors. The equilibrium constant for the reaction was determined. Standard thermodynamic properties of the reaction, such as enthalpy, entropy, and Gibbs free energy, were experimentally evaluated. The activity‐based two‐parameter Langmuir‐Hinshelwood‐Hougen‐Watson rate expression was used for reaction kinetics. The activity coefficients were calculated by the UNIFAC method. The kinetic parameters and the activation energy were evaluated from the experimental data. The experimental data and data predicted by the model were found to be in good agreement. [ABSTRACT FROM AUTHOR]

Batch and continuous adsorption studies were performed for heavy metal removal from the ternary metal system using wheat bran as an adsorbent. An adsorbent pellet was prepared using clay and chitosan as a binder. For batch adsorption experiments, the Box–Behnken design of response surface methodology was used to optimize the process parameters for adsorption. In our mixed metal continuous study, cadmium (70%–80%) and chromium (74%–80%) had shown a synergistic effect on copper removal leading to an increase in breakthrough and exhaustion time. In a continuous study, a higher breakthrough time was obtained for copper at a bed height of 0.15 cm, a flow rate of 5 mL/min and an initial metal concentration of 100 mg/L. The modeling and simulation of the continuous adsorption process were performed. The breakthrough curve obtained from the model and from experiments was compared and high R2 values up to 0.99 and low chi‐square and MAPE values up to 0.018% and 0.037% indicate good fitting of model and experimental data. Regeneration studies results show that good desorption efficiency is obtained using regenerated wheat bran. The adsorbent was regenerated and reused up to five cycles and it showed good desorption efficiency of up to 95% for copper, 79% for cadmium and 80% for chromium. [ABSTRACT FROM AUTHOR]