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Paleoproductivity variations off Morocco during Interglacial periods

Natural nanomaterials : reappraising the elusive structure of the nano-sized mi...

Ferrihydrite is natural ferric oxyhydroxide occurring exclusively nanocrystalline. With ideal formula 5 Fe2 O3 . 9 H2 O, ferrihydrite is quite abundant in sediments, weathering crusts and mine wastes, being characteristic of red pre-soils formed by loose weathered rock plus mineral debris (regoliths) and commonly designated as “2-line” or “6-line” on the basis of the broadened maxima observed in the X-ray di...

Decorative 18th century blue-and-white portuguese tile panels : a type-case of ...

Decorated glazed ceramic tiles are used as an ornamental art, constituting an important cultural heritage whose preservation is mandatory. Environmental conditions are responsible for the degradation of exposed ancient tile panels originating various pathologies, related to the development of microorganisms. This is the case of a valuable 18th century blue-and-white Portuguese tile panel called “Cura do Cego,...

Ascertaining the degradation state of ceramic tiles : a preliminary non-destruc...

Conserving the cultural heritage is a general concern and the use of non-destructive techniques to characterize ancient materials is important. Serious deterioration effects in environmentally exposed ancient glazed ceramic tiles arise from the development of micro-organisms (algae/fungi) within the pore system. Subsequent biodegradation processes are particularly harmful once the decorated glaze is damaged by ...

Molybdenite as a rhenium carrier : first results of a spectroscopic approach us...

The chemical and physical properties of rhenium render it a highly demanded metal for advanced applications in important industrial fields. This very scarce element occurs mainly in ores of porphyry copper-molybdenum deposits associated with the mineral molybdenite, MoS2, but it has also been found in granite pegmatites and quartz veins as well as in volcanic gases. Molybdenite is a typical polytype mineral w...

Scarce industrial commodities : a glance at the possible rhenium availability i...

Diagnostics of glaze pathologies in ancient (XVII-XVIII cents.) decorative blue...

Opportunities for recovering critical raw materials from mine wastes : the type...

A new light into old gold

Rhenium incorporation in molybdenite : first results of a XANES study