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The ability to analyze different electrochemical corrosion phenomena, in-situ, without requiring any form of electrode perturbation has strongly attracted the attention of corrosion researchers towards the application of electrochemical noise (EN) analysis method. With the ability to analyze stochastic and chaotic electrode potential and current fluctuations at E OCP , the EN analysis method is capable of providing information about the kinetics and mechanism of metallic corrosion with accuracy that can match conventional electrochemical techniques. Herein, we review the recent applications of EN analysis method to electrochemical corrosion research. We discuss briefly the theory behind the measurement of EN, and then highlight some of its application in the evaluation of corrosion inhibitors, pitting corrosion, coatings on metals, microbiologically-induced corrosion, as well as CO 2-corrosion. The drawbacks of the EN analysis method have also been highlighted and future considerations on the use of this important electrochemical technique have also been proposed.

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The raw carbon nanotubes (CNTs) were prepared by the floating catalyst chemical vapor deposition method. The raw carbon nanotubes were functionalized, impregnated with iron nanoparticles, and characterized using high resolution transmission electron microscopy (HRTEM), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and thermogravimetric analysis (TGA). The three types of these multiwalled carbon nanotubes were applied as adsorbents for the removal of bromate from drinking water. The effects of the pH, the concentration ofBrO3-anion, the adsorbent dose, the contact time, and the coanions on the adsorption process have been investigated. The results concluded that the highest adsorption capacities were 0.3460 and 0.3220 mg/g through using CNTs-Fe and raw CNTs, respectively, at the same conditions. The results showed that the CNTs-Fe gives higher adsorption capacity compared with the raw CNTs and the functionalized CNTs. The presence of nitrate (NO3-) in the solution decreases the adsorption capacity of all CNTs compared with chloride (Cl-) associated with pH adjustment caused by nitric acid or hydrochloric acid, respectively. However, the adsorption of all MWNCTs types increases as the pH of solution decreases.

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a b s t r a c tIn this work, the inhibitory effect of a commercial anti-scalant (Veolia Hydrex s 9209) on the calcium minerals of carbonate, sulfate and hydrocalumite (Ca/Al) clay deposition from seawater has been investigated. Different concentration factors and anti-scalant doses were studied by analyzing the water hardness and turbidity. The inhibitory effect of the investigated anti-scalant was efficient even at lower concentrations. The percentage inhibition decreases with increasing the temperature and increases with increasing the dose/amount of the anti-scalant. The carbonate scale inhibition was 499% and 98-99% at 50 and 70°C, respectively. The percentage inhibition of sulfate from hemihydrate was ranged from 80% to 87% for 2 and 8 ppm anti-scalant at 50°C. The inhibition of Ca/Al hydrocalumite deposition increases from 70% to 90% upon increasing the dose from 3 to 5 ppm, respectively. A recommended useful dose of antiscalant for seawater is 5 ppm.