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The present paper aims to study the preparation of polyaniline nanofibers through simple interfacial polymerization. Ammonium persulfate, hydrochloric acid and chloroform were used as oxidant, dopant and organic solvent respectively. Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction and Fourier Transform Infrared Spectroscopy (FTIR) techniques were used to analyze the product. FESEM results show that polyaniline has nano-fiber morphology. XRD results show the crystalline properties of polyaniline nanofiber, and FTIR results confirmed the formation of polyaniline in different monomer/oxidant molar ratios. This study provides a better understanding on the synthesis of uniform polyaniline nanofibers through interfacial polymerization.

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The microstructure and bio-corrosion behavior of binary Mg-xZn (x ¼ 1.25, 2.5, 4) and ternary Mg-Ca-xZn (x ¼ 1.25, 2.5, 4) alloys have been studied using scanning electron microscopy (SEM), electrochemical, and immersion tests. Microstructure analysis indicated that the binary Mg-Zn alloys are composed of primary a-Mg matrix and Mg 12 Zn 13 phases, while, ternary Mg-Ca-Zn alloys are composed of a-Mg, Mg 2 Ca, and IM1 (Ca 3 Mg x Zn 15Àx ) (4.6 x 12) phases or a-Mg, IM1 and IM3 (Ca 2 Mg 5 Zn 13 ) phases. Electrochemical results showed that Mg-4Zn alloy has lowest corrosion rate among binary alloys. At constant Ca content of 0.8 wt.%, the addition of Zn up to 1.25 wt.% decreased the corrosion rate, while further addition of Zn increased the corrosion rate of ternary alloys. Immersion tests results demonstrated that the formation of Zn oxide layer in binary Mg-Zn alloy and evolution of eutectic phase (a-Mg þ IM1 þ Mg 2 Ca) significantly retard the bio-degradation rate of the ternary alloys.

Microbiologically influenced corrosion (MIC) is a corrosion phenomenon that is destructive to many industries. This research aims to investigate on the MIC behaviour of a 304 stainless steel (SS) substrate in a nutrient rich simulated seawater inoculated with Pseudomonas aeruginosa bacteria. Atomic force microscopy, scanning electron microscopy and energy dispersive spectroscopy (EDS) techniques were used to analyse MIC behaviour of 304 SS. Atomic force microscopy was used to observe the degree of pitting corrosion on 304 SS due to the presence of P. aeruginosa bacteria. Scanning electron microscopy and EDS were used to analyse the biofilm layer formed on 304 SS. The considerable feature was the severe pitting corrosion of 304 SS due to presence of P. aeruginosa in biofilm state.