Influence of slag composition on the stability of steel in alkali-activated cementitious materials

Among the minor elements found in metallurgical slags, sulfur and manganese can potentially influence the corrosion process of steel embedded in alkali-activated slag cements, as both are redox-sensitive. Particularly, it is possible that these could significantly influence the corrosion process of the steel. Two types of alkali-activated slag mortars were prepared in this study: 100% blast furnace slag and a modified slag blend (90% blast furnace slag? 10% silicomanganese slag), both activated with sodium silicate. These mortars were designed with the aim of determining the influence of varying the redox potential on the stability of steel passivation under exposure to alkaline and alkaline chloride-rich solutions. Both types of mortars presented highly negative corrosion potentials and high current density values in the presence of chloride. The steel bars extracted from mortar samples after exposure do not show evident pits or corrosion product layers, indicating that the presence of sulfides reduces the redox potential of the pore solution of slag mortars, but enables the steel to remain in an apparently passive state. The presence of a high amount of MnO in the slag does not significantly affect the corrosion process of steel under the conditions tested. Mass transport through the mortar to the metal is impeded with increasing exposure time; this is associated with refinement of the pore network as the slag continued to react while the samples were immersed

Recruitment Policies and Recruitment Experiences in the French Foreign Legion

Perceptions of the French Foreign Legion have always been ambivalent. The Legion’s image as an alleged reservoir of criminals and runaways from all over Europe has been countered by notions of romantic legionnaires such as fostered in P. C. Wren’s novel Beau Geste (1924) or in Edith Piaf’s song ‘Mon Légionnaire’ (1936). Although an anachronism in the age of national armies largely based on compulsory military service, the French Foreign Legion has served as a model for the Spanish Foreign Legion, founded in 1920, and in Britain voices demanding the institution of a permanent British Foreign Legion emulating the French model would sporadically emerge in the nineteenth and twentieth centuries. Many stories, rumours and myths were related to Foreign Legion recruitment, including issues such as recruitment of criminals, underage or famous runaways as well as alcoholization and abduction of young men by secret recruitment agents. In the run-up to World War I, such notions were so widespread in Germany that Social Democratic MP Hermann Wendel would sneer in a 1914 Reichstag debate about a disease called ‘Legionitis, whose symptoms include discovering mysterious recruitment agents all over Germany’