Nazan Demir

Experimental study on the nickel (II) removal from aqueous solutions using silica fume with/without apocarbonic anhydrase

Abstract The silica fume is a fine-grain, thin and very high surface area silica. Although the silica fume is a waste material of industrial applications, it has become the most valuable by-product among the pozzolanic materials due to its very active and high pozzolanic property. In this study, the potential use of silica fume in the remediation of polluted heavy metal water to remove nickel ions is presented. For studying metal adsorption, 1 g of silica fume has been taken as adsorbent and then it has been suspended in 50 ml of 3 mmol dm−3 NiCl2, at pH between 3 and 9 and contacted batchwise in a thermostatic (t = 25°C ± 0.1°C) water-bath agitator for 1 h to enable equilibration of the sorbent and solution phases. The nickel concentrations in the samples taken from the silica fume treated aqueous solutions of polluted river water with/without apocarbonic anhydrase (apoCA) and NiCl2 solution have been determined by spectrophotometric method using dithizone. The nickel concentration in the samples of sili...

Fen Eğitiminde Dijital Teknoloji Ürünü Dinamik Görsel Kullanımı – Fen Bilgisi Öğretmen Adaylarının Algıları

This study investigated the perceptions of pre-service science teachers who viewed digital technology-generated dynamic visualizations such as animation, short-film and documentary throughout the teaching of atmosphere-related environmental problems (global warming, acid rain etc.) and renewable energy sources (energy of sun, wind, wave etc.). The working group consisted of 103 junior pre-service science teachers enrolled at a mid-size university in the west of Turkey and only 82 of those voluntarily participated in the treatment evaluation process. In the study, descriptive research design was used. “The scale of opinion about the use of dynamic visualizations” which had been revised from the previous version was used as quantitative data collection tool in the study involving quantitative and qualitative data collection tools. In addition, “the questionnaire of opinion about the use of dynamic visualizations” consisting of open-ended questions developed by the researchers was utilized to obtain in-depth data. The quantitative data were analyzed by using descriptive statistic while the qualitative data were analyzed through content analysis. The results of the analysis indicated that the pre-service science teachers overwhelmingly support the use of dynamic visualizations and believe that they enhance their learning experiences. However, according to the pre-service science teachers, using dynamic visualization in science classroom facilitates the understanding of concepts and also provides the retention of knowledge. Furthermore, the participants claimed that the lessons conducted with the help of dynamic visualizations were interesting, enjoyable, and motivating. Moreover, it was found that there was no difference between the female and male pre-service science teachers’ perceptions regarding the treatment. The findings of the study were discussed in terms of importance of the use of dynamic visualizations in science and environmental education