Investigating the Effectiveness of the Self-Esteem Educational Package in Elementary School Students

This study was conducted to investigate the effectiveness of the self-esteem educational package in elementary school students. For this purpose, through the available sampling method, 16 out of 43 students in grade three were selected three according to the inclusion criteria. The subjects were randomly divided into two groups and subjected to the Rosenberg’s self-esteem scale. The subject group of the study, in addition to their usual training, was trained twice a week in their self-esteem program, which was prepared by the author and its validity was confirmed by the experts. The control group followed their usual training and after eight sessions of training to the subject group, the mentioned tests were taken again from the two groups and the data were analyzed by the covariance analysis method. The 20th edition of SPSS software and one-way analysis of covariance test were used to analyze the data. The findings showed that, compared to the control group, the subjects’ scores in the self-esteem variable had increased significantly (P<0.05). As a whole, the findings indicated that the application of the self-esteem training program on elementary school students could result in an increase in self-esteem

Synthesis of graphene oxide/magnesium oxide nanocomposites with high-rate adsorption of methylene blue

A series of graphene oxide/magnesium oxide nanocomposites (GO/MgO NCs) were and applied for the removal of Methylene Blue (MB) from aqueous solutions. The prepared NCs were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectrum, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The results showed that MgO particles was successfully decorated on GO. The impacts of different experimental variables on the removal of MB including GO/MgO NCs dosage, pH, contact time, and initial MB concentration were investigated. The experimental analysis of adsorption isotherms indicated that adsorption data was best fit with the Langmuir isotherm model. Among the three different synthesized weight ratios of GO/MgO (5:1, 1:1, and 1:5), 5:1 ratio showed the maximum adsorption capacity as 833 mg/g, which is higher than any previously reported GO-based composites. The synthesized GO/MgO NC is also observed to have higher adsorption capacity for MB removal, in comparison with pure GO and MgO. The kinetic adsorption data was best described by pseudo-second-order kinetic model. The pH of point of zero charge (pH(pzc)) of GO/MgO NCs was determined to be 9.7, 10.5, and 10.5 for ratios 5:1, 1:1, and 1:5, respectively. The results revealed that electrostatic attraction can be the dominant mechanism of adsorption between GO/MgO NCs and MB for pH above pH(pzc); whereas for pH below pH(pzc), other adsorption mechanisms such as hydrogen bonding and pi-pi interaction may attribute to adsorption. The high adsorption capacity of GO/MgO composites, thus makes it a promising adsorbent for water and wastewater treatment. (C) 2016 Elsevier B.V. All rights reserved

Graphene oxide/magnesium oxide nanocomposite: A novel catalyst for ozonation of phenol from wastewater

© ASCE.Catalytic ozonation is a promising advanced oxidation technique for the removal of contaminants from water and wastewater. Graphene oxide (GO) is an oxidized derivative of graphene which contains epoxide, hydroxyl, and carboxyl groups with high surface area, and is being recently used for effective adsorption of pollutants in aquatic environments. In our previous work, we modified GO with magnesium oxide (MgO) and demonstrated the high-rate adsorption of methylene blue (MB) by the synthesized nanocomposite (NC). In this study, our synthesized NC is applied as a catalyst for catalytic ozonation of phenol in a laboratory scale batch reactor. The results showed that the catalytic ozonation significantly improved the mineralization of phenol compared to that of ozonation without the catalyst. The impact of experimental variables on oxidation of phenol, particularly GO/MgO NC dosage and reaction time is investigated. A possible mechanism for the catalytic ozonation of phenol is also proposed. Our results show promising application of the proposed technology for the removal of various organic contaminants from wastewater

Synthesis of graphene oxide/magnesium oxide nanocomposites with high-rate adsorption of methylene blue

A series of graphene oxide/magnesium oxide nanocomposites (GO/MgO NCs) were and applied for the removal of Methylene Blue (MB) from aqueous solutions. The prepared NCs were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectrum, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The results showed that MgO particles was successfully decorated on GO. The impacts of different experimental variables on the removal of MB including GO/MgO NCs dosage, pH, contact time, and initial MB concentration were investigated. The experimental analysis of adsorption isotherms indicated that adsorption data was best fit with the Langmuir isotherm model. Among the three different synthesized weight ratios of GO/MgO (5:1, 1:1, and 1:5), 5:1 ratio showed the maximum adsorption capacity as 833 mg/g, which is higher than any previously reported GO-based composites. The synthesized GO/MgO NC is also observed to have higher adsorption capacity for MB removal, in comparison with pure GO and MgO. The kinetic adsorption data was best described by pseudo-second-order kinetic model. The pH of point of zero charge (pH(pzc)) of GO/MgO NCs was determined to be 9.7, 10.5, and 10.5 for ratios 5:1, 1:1, and 1:5, respectively. The results revealed that electrostatic attraction can be the dominant mechanism of adsorption between GO/MgO NCs and MB for pH above pH(pzc); whereas for pH below pH(pzc), other adsorption mechanisms such as hydrogen bonding and pi-pi interaction may attribute to adsorption. The high adsorption capacity of GO/MgO composites, thus makes it a promising adsorbent for water and wastewater treatment. (C) 2016 Elsevier B.V. All rights reserved