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CaCO3 scaling on metal is closely related to its electrochemical corrosion. However, little attention has been paid to the influences of interfacial corrosion on scaling behavior. In this work, the local deposition behavior of CaCO3 on carbon steel with different corrosion types was investigated. Results reveal that the interfacial distribution of anodically released Fe2+ plays important roles in CaCO3 polymorph. For general corrosion, anodically released Fe2+ easily diffuses to all micro cathodic regions and suppresses pH increase by preferentially consuming cathodically produced OH– and interfacial O2, and its incomplete hydrolysis. This lowers CaCO3 nucleation driving force and favors aragonite deposition. In contrast, localized corrosion results in an uneven distribution of Fe2+ at carbon steel/water interface. Aragonite tends to deposit in the micro cathodic regions where Fe2+ ions easily arrive from the adjacent anodic sites, while this effect diminishes in the cathodic regions where fewer Fe2+ ions arrive.

The steam jet pump made by SAF 2205 duplex stainless steel (DSS) provides vacuum for vacuum distillation tower to improve the distillation efficiency of crude oil. The pump suffers from severe local wall thinning during service, especially at diffuser section. Failure analysis of the pump is carried out using traditional characterization techniques and computational fluid dynamics (CFD) simulation. The results show that the pump suffer from not only the electrochemical corrosion of acidic droplets forming in HCl-H2S-H2O environment, but also the mechanical erosion by high speed flow with a large value of wall shear stress. A vicious erosion-corrosion circle built by electrochemical corrosion together with mechanical erosion leads to severe damage at the diffuser section of steam jet pump.

We examine how the relationship between development and inequality at the societal level is perceived and evaluated by ordinary Chinese people. We hypothesize that because the Chinese have recently experienced rapid increases in both economic growth and social inequality, they tend to view economic development as a driving force of social inequality. To address this question, we conducted a social survey in 2006 in six Chinese provinces (n = 4,898). The survey data reveal that a large proportion of Chinese people have internalized a causal model in which they project high levels of inequality onto countries they view as more developed and low levels of inequality onto countries they see as less developed. However, results also show that a smaller proportion of Chinese believe in a negative relationship between development and inequality. Hence, the study reveals heterogeneity among ordinary Chinese in their perceptions of the causal relationship between development and inequality. Surprisingly, socioeconomic and demographic characteristics provide no explanatory power in explaining this heterogeneity.

In this paper, creep behaviour of Sn–3.8Ag–0.7Cu (SAC) lead-free solder under the collective effect of electromigration, stress and temperature was investigated. Firstly, the conventional creep test was improved so that high current density can be applied to the ribbon sample and serve as one of the experimental control variables. Experimental results indicate that creep rate of the SAC was greatly affected by electromigration (EM) and its linear dependence on current density and stress was revealed. Then a unified phenomenological creep model with variables of stress, temperature and current density was set up based on the fact that both the mechanisms of conventional creep and electromigration are vacancy diffusion type. Coefficients in the unified creep model were determined from the experimental results by curve fitting, and numerical results of the unified creep model are found to fit the experimental results quite well.