No abstract

No abstract

No abstract

No abstract

In the present work, Ag nanoparticles were added to polyurea coating in order to improve its antibacterial and electrochemical properties in sulfide-reducing bacteria-containing media. To this end, Ag nano-powder was mixed with two component polyuria, and then the antibacterial behavior of the nanocomposite coating was studied in sulfate-reducing bacteria (SRB)-containing medium. The results revealed the inhibitory effects of nanocomposite coating on the formation of SRB biofilms on the samples. Moreover, the SRB population decreased in contact with the Ag nanoparticles-mixed coating over 7 days. Investigation of the growth and activity of the bacteria represented the effective antibacterial properties of Ag nanoparticles in the polyurea matrix. Furthermore, EIS (electrochemical impedance spectroscopy) measurements indicated that the corrosion properties of the nanocomposite coating improved considerably over 7 days. The coating resistance increased 2 times by adding Ag nanoparticles after 1 day and 3.3 times after 7 days. In accordance with the same results, the charge transfer resistance increased 1.5 times and 1.1 times by adding Ag nanoparticles after 1 day and 7 days, respectively. The improvement in the protective properties of the nanocomposite coating are reflected in the increase in both film and charge transfer resistance.

In this study, thin films of aluminium nitride (AlN) are deposited on Nimonic 75 substrates using a 4 kJ Mather type plasma focus device (PFD) for 5, 10 and 15 focus shots. For the deposition of AlN films, a solid aluminium fitted anode was used instead of a copper anode. The PFD was operated with nitrogen gas at a pressure of 2 torr. X-ray diffraction results reveal the formation of a nanocrystalline AlN coating on the surface of the substrate. The crystallite size is dependent on the number of focus shots. The density of grains increased with an increase in the number of focus deposition shots, as illustrated by field emission scanning electron microscopy (FESEM). The FESEM images confirm the distribution of spherical grains for 15 focus shots. Energy dispersive X-ray spectroscopy spectra indicate the presence of expected constituent elements such as N and Al.

This study aimed to study the inhibitory effect of the Myrtus communis extract on the microbiologically influenced corrosion (MIC) induced by sulphate reducing bacterial (SRB) consortium in the cooling tower water. The SRB consortium was grown on the surface of the st37 steel and its effects on the surface corrosion were evaluated. The results of electrochemical measurements and microscopic observations revealed that the extract could significantly reduce the corrosion by inhibiting the SRB biofilm formation. The addition of the 0.781 mg ml −1 of the extract into the SRB medium led to a considerable reduction (about seven times) in the corrosion process of the st37 steel and kept it at an almost constant value. Based on Gas chromatographymass spectrometry analysis, 2-Furancarboxaldehyde, 5-(hydroxymethyl) (42.396%) was the most abundant compound identified in the plant extract. The molecular identification has proved that most population of SRB consortium was related to Desulfovibrio vulgaris species.

No abstract