Faik Özgür Karataş

Long-term wear on outside walls of buildings by sulfur dioxide corrosion

Abstract The effect of sulfate ions on the corrosion of concrete on outside walls of buildings was studied. The corrosion rate was very high during the early years and decreased with time. Corrosion-induced cracking of concrete can be simulated by sulfate formation with sulfur dioxide (SO 2 ) at the concrete interface for a long period. Excessive alkali sulfate formation at the concrete surface causes destructive volume expansion. In general, the age of concrete is highly correlated with its sulfate content and water solubility.

What Do We Know About Students’ Beliefs? Changes in Students’ Conceptions of the Particulate Nature of Matter from Pre-instruction to College

This chapter summarizes the results of 28 studies of students’ ideas of the particulate nature of matter (PNM) across a broad range of ages, from early elementary to college-level students. The primary source of data for these studies was clinical interviews, although paper-and-pencil tests and students’ drawings have also been used. The literature reviewed in this chapter suggests that students’ views of the PNM vary from a belief in a continuous form of matter to sophisticated ionic and molecular representations. Although students’ ideas often became more sophisticated with age, inappropriate macroscopic ideas were still incorporated in many students’ responses. A transitional model is proposed for the development of conceptual understanding of the PNM in which students can simultaneously hold different views of the nature of matter for different substances or phases.

Mentoring in-service chemistry teachers: acquirements as mentees

Abstract The aim of this study is to identify a group of chemistry teachers’ (mentees) acquirements of mentoring program by analyzing their reflective journals. Four mentees participated in this study and they met with their mentors once a week for eight consecutive weeks. The mentees devised lesson plans as well as activities during the mentoring sessions. After each mentoring session, the mentees were asked to reflect the process and their gains to their journals. The journals were analyzed in two stages; content analysis of the journals and the analysis of the mentees level of reflections. The analysis of the mentees’ journals showed that the mentorship program supported the mentees to improve their pedagogical content knowledge; allow them to utilize various methods, techniques, and materials in their lessons. Besides, the mentees indicated that they performed chemistry courses more effectively with the help of the acquirements from the mentoring sessions. The result of this study showed also that mentors can play key roles in supporting professional developments of teachers. It is suggested that rehearsing lesson plans before going into the classroom would make the mentoring sessions more beneficial.