1. Federal Institute of Education, Science and Technology of the Sertão Pernambucano, Petrolina 56314-520, Brazil
2. CEMMPRE—Electrical and Computer Engineering Department, University of Coimbra, FCTUC, Polo 2, Pinhal de Marrocos, 3030-290 Coimbra, Portugal
3. Research Group on Electrospinning and Nanotechnology Applications, Department of Materials Science, Federal University of São Francisco Valley, Juazeiro 48902-300, Brazil