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The chemical behaviour within the occluded cell of simulated cast iron artefact in 3.5 percent NaCl solution has been investigated by means of a simulated occluded cell. It was observed that the pH value and the amount of Cl⁻ migration in the occluded cell were related to the quantity of passing electric current. Electrochemical techniques were capable of providing information on the behaviour of the cast iron in a simulated occluded cell at various time intervals. The results of potentiodynamic polarisation and impedance measurements indicated that corrosion potentials became more negative and the cast iron was corroded more seriously. SEM micrographs clearly revealed the morphologies of specimens after simulated occluded cell galvanostatic tests for different time intervals at 1 mA/cm² anodic current density. An auto‐catalysing process was responsible for the enrichment of chloride ions in occluded cell which was confirmed by Energy Dispersive Spectroscopy (EDS).

The main purpose of this study was to investigate the corrosion behaviour of simulated archaeological iron in Cl⁻, NO₃⁻ and HSO₃⁻ bearing pollutants.

Periodic wet‐dry test, potentiodynamic polarization experiments and surface tension tests were used to study the rule of corrosion rate. Scanning Electron microscopy with EDAX, stereoscopic microscopy and X‐ray diffraction were also used to identify the corrosion products and mechanism. Weight loss measurement, electrochemical theory, as well as ions adsorption theory and penetration theory were used to explain the different corrosion behaviour.

The experimental results demonstrated that the attack of anodic ions to the metal at the initial corrosion stage showed great agreement with their surface activity. However, as corrosion progressed, the different reaction mechanisms and the penetration effect of anions as well as the characteristics of the corrosion products (intermediate products and final products) begin to control the corrosion process.

The initial corrosion rate was found to show agreement with the surface activity of anions. From a new viewpoint, this paper explains the different corrosion behaviour of Cl⁻, NO₃⁻ and HSO₃⁻ anions to simulated archaeological iron and offers reference to the individual who pursues in corrosion and protection of metal.

The purpose of this paper is to study the failures spread in complex power grids, and what topology of power grids is best for preventing or reducing blackouts.

Based on the study of cascading failure models of complex power networks, an extended dynamical cascading failure model is proposed. Based on this model, two representatives of the complex power grids, the small‐world network and the scale‐free network, were simulated for line cascading failure. The power loss caused by cascading failures and the spreading speed of cascading failure are discussed.

Power loss caused by cascading failures in the small‐world network is much larger than that in the scale‐free network, and the speed of cascading failure propagation in the small‐world network is much faster than that in the scale‐free network.

The establishment of the dynamical cascading failure model considering other protection devices needs further study.

The results of this study can be beneficial in system planning and upgrading.

An extended dynamical cascading failure model is proposed and cascading failures in different topology of power grid are discussed.