Faruk Gökmeşe

Preparation and Characterization of PVA/PVP Nanofibers as Promising Materials for Wound Dressing

The PVA/PVP, PVA/PVP with 5% and 10% chitosan and PVA/PVP-Iodine fibers were produced via electrospinning technique. Their morphological and chemical characteristics were examined with SEM, TGA, FT-IR, viscometer and four-point probe conductivity measurement apparatus. The addition of chitosan increased the viscosity and the electrical conductivity of the polymer. The increase chitosan contents resulted in the diameters of the fibers smaller than expected. This was attributed to the increase in the viscosity of the solution and the electrical conductivity of the resulting fibers. The DSC results show that iodine was efficiently cross-linked with the polymer, forming an amorphous structure.

Preparation and Characterization of Polyvinyl Alcohol Based Copolymers as Wound Dressing Fibers

Biocompatible polyvinyl alcohol/polyethylene glycol and polyvinyl alcohol/polypropylene glycol copolymer mats were prepared by electrospinning. The composite fiber mats were subjected to detailed physical analysis complemented by scanning electron microscopy and Fourier transformations infrared spectroscopy. Scanning electron microscopy images showed that the morphology and diameters of the fibers were mainly affected by the types of polymers and their copolymer compositions. Microbial culture results showed that among the tested fibrous mats polyvinyl alcohol/50% polyethylene glycol gave the best results in preventing the cell attachment and proliferation. This novel electrospun matrix would be used as potential wound dressing material for skin regeneration. GRAPHICAL ABSTRACT

Fabrication and Characterization of Boron Doped Ni/Zn Acetate Nanofibers

This study is related to the preparation of boron doped Nickel/Zinc metal fibers prepared by the use of electrospinning technique. The originality of this study is the addition of boron to metal acetates. The addition of boron did not only increase the thermal stability of the fibers, but also increased their diameters, which gave stronger fibers. The FT-IR spectra of the fibers were in good accordance with literature. The differential scanning calorimetry (DSC) results indicate that the glass transition (Tg) and melting temperatures (Tm) showed great change with the addition of boron and boron doped fibers were observed to degrade at higher temperatures. The SEM appearance of the fibers showed that the addition of boron resulted in the formation of cross linked bright surfaced fibers.

Electrochemical Investigation of Zinc(II)-Furdap Amide Complex in DMSO Medium

The electrochemical behavior of Zinc(II)-furdap amide complex has been investigated by the use of several electrochemical methods in DMSO on platinum electrode. Both the ligand and the complex gave one electron transfer re- duction. Although there was no oxidation peak observed corresponding to the reduction of ligand, there was a correspond- ing oxidation peak appeared for the complex. The number of electrons transferred was calculated as 1 by the use of bulk electrolysis, rotating disc electrodes employing Kouteck� -Levich equation. The reversibility tests revealed that the reac- tion followed a quasi reversible mechanism. The mechanism was also confirmed by simulation studies. ks and  values were found to be 1.0 10 -7 cm s -1 and 0.4, respectively. The diffusion coefficient (D) was found as 6.93  10 -5 cm 2 s -1 by the use of Cottrell slope obtained from chronoamperometry experiments and ultra micro disc steady state current (iss).

A Simple and Rapid Method for Preparing Carbon Nanopore Electrode Ensemble (CNEE) by Coating A Commercial Glassy Carbon (GC) Electrode with Chromate

A simple preparation method for carbon nanopore electrode ensemble (CNEE) was reported. The CNEE consists of a number of pinholes which remain after coating a carbon surface with chromate. The transformation from transient to steady-state voltammetric behavior of carbon surface was presented. The effect of electrochemical technique to structure of chromate film was investigated. The optimum deposition time and optimum concentration of chromate solution for coating carbon surface substantially were determined for bulk electrolysis (BE) technique. On the other hand for cyclic voltammetry (CV), the effects of scan rate, number of cycle and coating solution concentration on forming uniform partly-insulating layer have been examined. The CNEE prepared by BE technique showed larger hysteresis which means more resistivity than the one prepared by CV. Under the optimum coating conditions the thinner and more useful CNEE with lower resistivity can be prepared by CV. Keywords: Carbon nanopore electrode ensemble (CNEE); chromate; steady-state current; radial diffusion; microelectrode DOI: 10.17350/HJSE19030000025 Full Text: