YASEMİN GULECAL-PEKTAS* Institute of Science and Engineering, University of Istanbul, Istanbul, Turkey *Corresponding author: Y. Gulecal-Pektas, Institute of Science and Engineering, University of Istanbul, Istanbul, Turkey; e-mail: ygulecalpektas@gmail.com Submitted 3 November 2014, revised 10 April 2015, accepted 19 April 2015 DOI: 10.5604/17331331.1197277 Abstract...