The inhibition and synergistic effect of three kinds of oxygen-containing organic compounds (i.e. sorbitol, glucose and ascorbic acid) with sodium dodecyl benzene sulfate (SDBS) on the corrosion of steel rebar in 3.5% NaCl (mass fraction) saturated Ca(OH)₂ solution were investigated using linear polarization, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Then the relevant mechanism of the corrosion inhibition and synergistic effect was discussed in terms of quantum chemical calculations and hard and soft acids and bases (HSAB) principle. The results indicated that the inhibition efficiency of the oxygen-containing compounds increased in the follow order: sorbitol＜glucose＜ascorbic acid, the highest inhibition efficiency of 96.9% was obtained for the inhibitor ascorbic acid, and had a positive correlation with their absolute hardness as Lewis bases in alkaline chloride solution. A significant synergistic effect appeared when three organic compounds mixed with SDBS in different portions, however, the synergistic effect of sorbitol with SDBS was the strongest.

As it is known that the existence of a rust scale on a steel surface may complicate the electrochemical corrosion process of the steel, thereby it is difficult to accurately measure the corrosion rate of carbon steel by traditional electrochemical methods. In this paper, weight-loss method and different electrochemical tests such as polarization curves (PC), electrochemical impedance spectra (EIS) and linear polarization resistance (LPR) were used to study the corrosion behavior of the Q235 carbon steel immersed in seawater for 1 a. The results show that the corrosion rates measured by both the electrochemical and weight-loss measurement show the same degressive trends during a short immersion period (for about 8 weeks), while those measured by electrochemical measurement turn to increase after 8 weeks' immersion in seawater. The longer the immersion time is, the bigger the deviation occurs for the corrosion rates measured by the two kind methods. It is believed that the rust scale presented on the electrodes had a great influence on its corrosion behavior. The evolution of phase constituents of the corrosion products on the rust steel was characterized by XRD. There is an obvious increasing of β-FeOOH in the corrosion product accumulated on the carbon steel with the immersing time going, and the reductive reaction of β-FeOOH during the electrochemical test process leads an overestimate of the corrosion rate, which caused the deviation between weight loss method and electrochemical tests. In order to solve this problem, the electrode was pretreated by a cathodic galvanostatic polarization with current density of -25 μAcm^-2 to counteract the reduction current during the electrochemical test process. After the pre-polarization, the electrochemical measurement results coincided well with weight loss, which means this pre-polarization showed a good calibration of the deviation between the two measurement methods.

The polarization behavior of X100 and X80 pipeline steel in 0.5 mol/L NaHCO₃ solution were analyzed by potentiodynamic polarization, and the growth mechanism and semiconductor properties of both passive films were investigated using current density versus time curves and Mott-Schottky measurement, and the density and diffusion coefficient of point defect in passive films were calculated by means of capacitance measurement and point defect model (PDM). The results showed that the growth process of the two passive films formed on pipeline steels was controlled by electromigration and dissolution-deposition process, and the conductive characteristics of the two passive films belonged on n-type semiconductor. However, in comparison with X80 steel, X100 steel exhibited lower corrosion current density and passive current density, but a higher pitting breakthrough potential. The passive film on X100 steel had a lower donor density and point defect diffusion coefficient. Therefore, X100 steel displayed a better general corrosion and pitting corrosion resistance than X80 steel.

The corrosion behavior of Q235 steel in a sulfate-reducing bacteria (SRB) solution in the presence and absence of magnetic field (MF) respectively was investigated by means of mass loss method, electrochemical techniques and surface analysis methods. The results showed that MF could inhibit the corrosion of Q235 steel to certain extent. The measured impedance implied that the MF delayed the formation of SRB biofilms on Q235 steel. SEM observation results indicated that the application of the MF resulted in homogeneous and compact biofilms with high adhesion to the surface of electrode. After removing the corrosion products, the corroded surface of Q235 steel without MF showed many corrosion pits and several corrosion cracks, while that with MF was much more uniform. It implied the application of MF could effectively inhibit the microbiologically influenced corrosion of Q235 steel.

The inhibition effect of Na₂MoO₄-organophosphorus A complex inhibitor on the corrosion of carbon steel in 55%LiBr+0.07 mol/L LiOH solution was studied by weight-loss tests, electrochemical measurements, AFM and EMPA. The results show that Na₂MoO₄-organophosphorus A complex inhibitor performed excellent inhibition in the solution. When its concentration reached 800 mg/L in 55%LiBr+0.07 mol/L LiOH solution at 240 ℃, the corrosion rate of carbon steel decreased to 43.2 μma^-1, the anodic passivation region broadened and the passive current density of carbon steel decreased, the inhibition efficiency was 94.4%. At the same time, the charge transfer resistance increased. The compact compound film formed on the surface of carbon steel in 55% LiBr+0.07 mol/L LiOH solution containing the inhibitor. The film with island structure was mainly composed of iron oxide and molybdenum oxide.

A micro arc oxidation (MAO) ceramic film on LY12 Al alloy was prepared by using bipolar pulsed power supply with changing cathodic current density (j_c) while keeping a constant anodic current density (j_a). The morphology, barrier property and practical service performance of the film were studied by scanning electron microscope (SEM), electrochemical impedance spectroscopy (EIS) and neutral salt spray test. Then, the effect of j_c on the film compactness was analyzed. Experimental results showed that the j_c value was a key factor responsible to the film compactness. The film prepared by an appropriate j_c value exhibited a good compactness, however, by a value above or below which the compactness of the films became worse due to that the electro-sparks ununiformly distributed throughout the Al alloy surface. When j_a=5 A/dm² and j_a∶j_c=1∶1, the MAO film on LY12 alloy showed the best compactness and protection performance.

The effect of pseudomonas on electrochemical corrosion behavior of 45 carbon steel was comparatively studied in seawater and a culture medium with and without the presence of pseudomonas, by means of microbiological analysis, weight loss method, corrosion potential measurements, EIS, potentialdynamic polarization curve and SEM, etc. The results showed that both pseudomonas and the medium exhibited inhibiting effect for the steel. Organic compounds in the medium could be absorbed onto steel surface and change the cathodic and anodic reaction of the corrosion process. The mechanisms of the effect of pseudomonas on corrosion behavior varied with immersing time: at the initial stage, the dissolved oxygen concentration in the environment was reduced by bacteria metabolism, which slowed down the corrosion rate. By prolonging the corrosion time, however, the partly quantitative accumulation of pseudomonas metabolites, which include alkaline substances and siderophores, finally accelerated the corrosion rate of the steel. Rich nutritious contents in the medium could promote mass propagation of pseudomonas, thus accelerated the influence of pseudomonas on corrosion behavior.

The semiconductor property of oxide films formed on 316L stainless steel in high temperature water was investigated by photoelectrochemical responses technique. The photocurrent spectra of the oxide film formed on 316LSS in water at 288 ℃ showed three major characteristics: a band gap energy of 2.3 eV was attributed to the presence of Fe₂O₃, and/or Ni(OH)₂; a band gap energy of 2.9 and 3.5 eV was attributed to Cr₂O₃ and a band gap energy in the range of 4.1 ~ 4.4 eV was attributed to the spinel phase Fe_1-xNi_xCr₂O₄. Considering the relation of the photocurrent to the applied potential, it follows that the oxide film on 316L in high temperature water indicated an n-type semiconductor. Therefore, the photoelectrochemical responses technique, with full information about the photocurrent and the dephasing angles of the oxide films，represents a sensitive and powerful way to locally analyze the various oxide phases in the oxide scale.

The corrosion behavior of pure copper and copper-clad steels in soil at Dagang district was investigated by burying test in nature field for one year with weight-loss measurement, as well as macro-morphology observation, characterization of corrosion products by SEM and XRD. The results showed that the corrosion rates for pure copper, electroplating copper-clad steel and continuous casting copper-clad steels are 1.01, 1.05 and 1.07 g/(dm²a), respectively. The average corrosion rates of electroplating copper-clad steel and continuous casting copper-clad steel are roughly equal, and that of pure copper is slightly lower than copper-clad steels. Inhomogeneous general corrosion occurs mainly on the pure copper and copper-clad steels in soil at Dagang district, with the different corrosion degree. The corrosion products of pure copper and copper-clad steels consist of Cu₂O, Cu(OH)₂, CuCl.

In order to prolong the service life of grounding grid for electric power station, the corrosion rate of grid without and with protection measures was evaluated by weight-loss method and electrochemical method respectively. The advantages and disadvantages of corrosion inhibitor, sacrificial anode cathodic protection and combined measure of corrosion inhibitor and sacrificial anode cathodic protection are compared and analyzed. The results show that three inhibitors of 1% of Na₂MoO₄, 2% of (NaPO₃)₆ and 4% of Na₂SiO₃ all show good efficiency in corrosion inhibition on Q235 steel grounding grid. The corrosion rate of grounding grid nearly decreased to 0.1200 mm/a with an inhibition efficiency about 70%. When (NaPO₃)₆+Na₂MoO₄ is used as mixed inhibitor, the corrosion rate of Q235 steel decreased from 0.4667 to 0.0873 mm/a with an inhibition efficiency up to 81.3%. Furthermore, by using magnesium sacrificial anode for cathodic protection, the corrosion rate of Q235 steel decreased from 0.2671 to 0.0639 mm/a with an inhibition efficiency up to 76.1%. By using combined protection measure of corrosion inhibitor plus sacrificial anode，the corrosion rate of Q235 steel decreased from 0.3342 to 0.0260 mm/a and inhibition efficiency is up to 92.2%.

Ti-based oxide-coated anodes have been widely utilized in trivalent chromium solution, but few in hexavalent chromium plating process. In this paper, by means of Hull cell, electrochemical measurement, long term stability test, the performance of DSA (IrO₂, Ta₂O₅) and DSA (IrO₂, Pt) anode in hexavalent chromium process is studied in comparison with tin-lead alloy anode. The results show that DSA anode has larger active surface area, lower oxygen evolution potential and better electrocatalytic activity in chromium solution, especially DSA (IrO₂, Pt) anode has the best electrocatalytic activity at high current density region. However, due to the presence of F^- additives in plating bath the Ti-based coated anodes exhibit poorer stability and shorter lifetime compared to the lead-tin anode.

The effects of 1.10-phenanthroline on the utilization of formaldehyde and copper deposition behavior during electroless copper plating was studied by measurement of the formaldehyde in electrolyte in real-time,  polarization curves, electrochemical impedance spectroscopy (EIS) and scanning Kelvin probe (SKP). The morphology and microstructure of copper coating was characterized by SEM and XRD. The results showed that 1.10-phenanthroline can accelerate the oxidation of formaldehyde and increase the utilization of formaldehyde. When 1.10-phenanthroline was added to electrolyte, the resistance of electrolyte reduced, the current density at mixed potential increased, the surface potential of copper at electrolyte moved negatively, and then the copper deposition rate increased. The utilization of formaldehyde rose from 28% to 39%, the deposition rate increased by 50% when 1.5 mgL^-1 1.10-phenanthroline was added to electrolyte. Besides, 1.10-phenanthroline is helpful to obtain uniform and fine copper coating, and increases the preferred orientation of Cu(111).

A novel Zn-22Al-Mg-Re alloy coating was prepared on Q420 steel substrate by arc spraying technology, and the microstructure, adhesive strength and corrosion resistance of the coating were characterized by SEM, copper accelerated acetic acid salt spray test (CASS) and electrochemical measurement in comparison with Zn and Zn-15Al coating. The results show that, the Zn-22Al-Mg-Re coating exhibits lower passivation potential with lower passivation current, because of its ability to form a very stable, adherent, small acicular, well self-sealing protective corrosion products film, the cathodic protection effectiveness and corrosion resistance of Zn-22Al-Mg-Re coating is better than Zn, Zn-15Al coating.

Al₂O₃/organosilicone/SiO₂ hybrid sol was prepared by the method of sol-gel with tetraethyl orthosilicate (TEOS), methyl triethoxysilane (MTES), diphenyl dimethoxy silane (DDS) and aluminium tri-sec-butoxide as raw materials. Then a hybrid coating was obtained by drying at 100 ℃ for 12 h. The result of Fourier transform infrared spectroscopy (FT-IR) showed that the Al—O—Si bond was formed in the Al₂O₃/organosilicone/SiO₂ hybrid materials. The electrochemical impedance spectroscopy (EIS) of the coating immersed in 3.5%NaCl solution for different times was studied. The equivalent circuits were established according to the impedance spectral characteristics. The corrosion resistance of the hybrid coating was discussed based on the equivalent circuit and fitted results of electrochemical impedance spectroscopy. The results indicated that the corrosion resistance of the Al₂O₃/organosilicone/SiO₂ hybrid coating was excellent in 3.5%NaCl solution.

The paper numerically discusses the influence of various aspect ratios (a/2c) of semi-elliptical corrosion pits on stress distribution and stress concentration factor (K_t) in round bars under tension or bending loading. By constructing a series of three-dimensional semi-elliptical pitted models with different pit diameter (2c) between 80 and 1200 μm, and pit depth (a) between 80 and 1100 μm systematically, it can be seen that stress concentration factor is not only affected by pit aspect ratio, but also the type of loading mode. Therefore, the rules of stress concentration factor can be established for a wide range of aspect ratio of corrosion pits. Then the comparison the present results with that of Cerit is conducted. At last, a fitted formulation of the relationship between K_t and a/2c is obtained, by which it is expected to be of convenience to find the value of stress concentration factor in practice of engineering and research.