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Basal ice microbiology at the margin of the Greenland ice sheet

“…Measurements were repeated after 8.5 and 20 hours. Mossbauer spectroscopy was performed on solid ice facies sediment in order to determine the presence of various Fe-containing minerals (Greenwood and Gibb, 1971; Stevens and others, 1998; Bruun and others, 2010). Presence of bioavailable nanoparticulate Fe was determined by treating the solid ice facies sample with an ascorbate solution (FeA), which extracts fresh, nanoparticulate ferrihydrite, and subsequently with a sodium dithionite solution (FeD), which extracts aged, nanoparticulate ferrihydrite and goethite, hematite and lepidocrocite, following the protocol by Raiswell and others (2008b, 2009).…”

Cation exchanged Fe(II) and Sr compared to other divalent cations (Ca,Mg) in the bure Callovian–Oxfordian formation: Implications for porewater composition modelling

“…Consequently, different quadrupolar hyperfine parameters were chosen in a second stage amongst those available in the literature (e.g. in Stevens et al, 2005) for the identified phase by microscopic techniques in the samples and vice-versa. Finally, only the proportions of each Fe component were refined, thereby allowing a quantitative analysis of the sample.…”

Influence of enamel ageing on mechanical properties and phase composition of the steel–enamel system

“…A further Fe 2C doublet represents a dominant component of the spectrum and, following its hyperfine parameters, it can be assigned both to Fe 2C atoms diffused from the oxidized steel surface 22 and ferrous ions in the fayalite structure. 20 Despite the similar qualitative phase composition of differently aged enamels, the mechanical properties of samples are significantly different. The microhardness is higher in a case of enamel applied after 30 days (8952 MPa) in comparison with the value obtained for that applied after 1 day (6690 MPa).…”