11 research outputs found
New filovirus disease classification and nomenclature
Filoviruses, the members of the family Filoviridae, are
currently classified into one proposed and five established
genera (Supplementary Table 1). Of the twelve
described filoviruses, six have been identified as aetiological
agents of naturally occurring human disease
outbreaks
Corrosion of Stainless-Steels in Chloride Solution - An Xps Investigation of Passive Films
Five commercial steels ranging from the martensitic stainless steel containing 12% chromium to the superferrite containing 29% chromium, 4% molybdenum, and 2% nickel have been studied by XPS. In addition, a pure iron-chromium alloy containing 7% chromium has been investigated. Armco iron and pure chromium (99.99%) were included as references. The formation of the passive films (or corrosion) occurred in deoxygenated 0.1 M NaCl solution (pH=5.6), from which the samples were transferred directly to the XPS chamber under controlled atmosphere (Ar). Concentration profiles (at.-%) of the alloy constituents in their oxidized and metallic states have been determined separately from the measured XPS depth profiles. For c≳= 12% chromium the passive films have the following structure: there is a depletion of Cr in the inner region, followed by an enrichment (concentration maximum) in the central region of the films. The height of this maximum increases, and its position shifts towards the surface with increasing chromium content in the alloy. The outermost monolayers are rich in water and hydroxyl groups. Various significant properties of the films change drastically at the critical chromium concentration of about 12%. This behaviour is rather independent of the other components (Mo, Ni, Cu) present in the alloys and is discussed in terms of a phase transition in the films which is controlled by the chromium concentration