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To investigate the effects of anodic polarization on the corrosion behavior and re-passivation behavior of martensitic stainless steel in a chloride ion environment， electrochemical testing methods including cyclic polarization， constant potential polarization， and electrochemical impedance spectroscopy (EIS) were employed.Additionally， the influence of anodic polarization potential on the corrosion resistance of 1Cr12Ni3Mo2VN stainless steel was studied using confocal laser scanning microscope (CLSM)， scanning electron microscope (SEM)， energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS).The study analyzed the behavior processes of pitting and re-passivation of the material， as well as the relationship between corrosion resistance and the composition of the passivation film.Results showed that no pitting corrosion was observed on the surface after polarization at a low potential in the passivation zone.The content of Cr2O3 and Fe2O3 in the passivation film was found to increase， while the content of hydroxides decreased， which enhanced the stability of the passivation film and improved the material's corrosion resistance.When the passivation area was polarized at a high potential， an inductive arc appeared in the lowfrequency region of the electrochemical impedance spectrum， and a stable pitting corrosion was formed on the material's surface.The pitting holes were semi-ellipsoidal， and the content of Cr and Mo in the surface layer of the pitting holes increased，while the content of Fe and Ni decreased.After the mixed potential dropped to the protection potential， re-passivation occurred.The repaired passivation film was thinner， the impedance value decreased， and the pitting sensitivity increased.

In order to analyze the impact of the waste heat utilization environment in phosphate compound fertilizer industrial production on the corrosion behavior of steam turbine rotors, various methods such as the mass loss method, laser scanning confocal microscopy (CLSM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical tests were employed. The corrosion behavior and patterns of the steam turbine rotor material, 2Cr-1Ni-1.2Mo-0.2V steel in 120 mmol/L NH4H2PO4 solution at an external temperature of 25 ℃ were investigated. Results showed that 2Cr-1Ni-1.2Mo-0.2V steel underwent uniform corrosion. The corrosion rate first rapidly decreased and then slowly decreased, gradually stabilizing towards 0.2 mm/a. When the NH4H2PO4 concentration was 120 mmol/L and the temperature was 25 ℃, the service life of 2Cr-1Ni-1.2Mo-0.2V steel was determined to be 7.5 a. The corrosion product film of 2Cr-1Ni-1.2Mo-0.2V steel in NH4H2PO4 solution was composed of Fe3(PO4)2, FePO4, Fe(OH)3, FeOOH, and Fe3O4. As the immersion time prolonged, the coverage, compactness and thickness of the corrosion product film were observed to increase, and Cr was found to be enriched in the corrosion product film, thereby enhancing the corrosion resistance of 2Cr-1Ni-1.2Mo-0.2V steel.

To study the effect of high Cl- environment on the corrosion of aluminum rich phosphate coatings, the corrosion behavior of phosphate coatings in high Cl- environments was analyzed using electrochemical testing methods such as open circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy, combined with scanning electron microscopy and laser confocal microscopy. Results showed that the aluminum-rich phosphate coating had a double-layer structure. Phosphate coated Al powder inside the coating provided excellent shielding performance. With the increase of Cl- concentration in the solution, the corrosion tendency and corrosion rate increased, and the corrosion resistance of the coating decreased. Moreover, aluminum-rich phosphate coatings corroded first at cracks and defects when the concentration of Cl- was low. With the increase of Cl- concentration, the corrosion of phosphate would cause the Al powder in the outer surface and the inner of coatings to fall off, and then the corrosion pits were formed. Furthermore, the corrosion pits tended to expand outward and increase in size, accelerating the corrosion of the coating and the substrate.

Soil salinization is a manifestation of land degradation caused by the combined effect of natural processes and human activities. This issue is particularly common in irrigation districts, where various factors exacerbated by frequent human interventions influence soil salinity. To prevent soil salinization, it is essential to have a comprehensive understanding of soil water-salt transport mechanisms in irrigation districts with frequent human activities. After reviewing the factors that influence soil water-salt transport in irrigation districts and the characteristics and applications of water-salt transport model, we propose a potential direction for simulating water-salt transport in irrigation areas. The formation of salinization in irrigation areas is closely related to natural factors such as climatic aridity, terrain, seasonal soil freeze-thaw cycles, groundwater salinity, and parent material of soils, as well as anthropogenic factors such as irrational irrigation practices, agricultural methodologies, and fertilization regimes. To understand the process of water- salt transport, soil water- salt transport models are effective tools. The commonly used models for water-salt transport include water-salt balance models, physical models, and statistical models. They are mainly used to optimize irrigation water-saving regimes and drainage management for salinity control at the field scale. However, applying these models at the regional scale presents challenges due to the difficulty of obtaining observational data to calibrate and validate models that involve soil water-salt transport processes and crop growth. The rapid development of modern large-scale irrigation districts has changed the spatiotemporal distribution of soil water-salt transport. However, the continuous improvements of the model and the rapid development of computer technology have provided possibilities for investigating the spatiotempo-ral evolution mechanisms of water-salt transport in large-scale irrigation districts. Future models should focus on strengthening the soil water-salt transport mechanisms based on ecological safety. It is recommended to develop a multi-process water-salt transport model that is coupled with a climate model or an economic model. [ABSTRACT FROM AUTHOR]

Byline: Huimin. Meng, Cunhuo. Jiang Sir, A 28-year-old Chinese female presented with a 10-year history of a nodule on her left palm [Figure 1], which was slow-growing. In the previous [...]