Non-destructive characterisation of the Elephant Moraine 83227 meteorite using confocal Raman,micro-energy-dispersive X-ray fluorescence and Raman-scanning electron microscope-energy-dispersive X-ray microscopies

Analytical and Bioanalytical Chemistry - The application of a non-destructive analytical procedure to characterise the mineral phases in meteorites is a key issue in order to preserve this type of...     

Analytical methodology to evaluate the Terrestrial Weathering of Libyan Desert Glasses and Darwin Glasses after their formation

Analytical and Bioanalytical Chemistry - Libyan Desert Glasses (LDGs) and Darwin Glasses (DGs) are impact glasses produced by the impact of an extraterrestrial body into the Earth million years...     

Raman and SEM‐EDX analyses of the ‘Royal Portal’ of Bordeaux Cathedral for the virtual restitution of the statuary polychromy

The chemical analysis of the remains of paintings from the Royal Portal of Bordeaux Cathedral was carried out by in situ analytical techniques and by laboratory techniques after sampling. Even though, nowadays, portable systems have a good performance and provide reliable results, in the present case, the in situ approach failed, and the analysis had to be carried out in the laboratory. The obtained results were used to propose a virtual restitution of the polychromy and to have an idea of how this portal was when it was built in the XIII century. During the analysis, the degradation process of pigment azurite was studied through the determined decay products, such as copper oxalate (moolooite) and copper basic sulfate (brochantite). This degradation seems to occur because of the presence of oxalic acid in the chemical system, as other calcium oxalates (weddellite) were identified as a degradation product of calcareous support. Copyright © 2015 John Wiley & Sons, Ltd.     

From Portable to SCA Raman devices to characterize harmful compounds contained in used black slag produced in Electric Arc Furnace of steel industry

Black slag from steel production is an industrial waste used as secondary material for some applications (forest tracks, cement, etc.). When it disposed to the open air, little is known about possible side effects that could appear with time. To foresee those side effects, various Raman equipments were used. This analytical strategy has been applied to six different black slag. Four of them were obtained from two steel producers (two original and two with treatment of ‘inerting’), and the other two sampled in civil construction works, which supposedly should be treated. Results showed the original mineral phases of the samples (iron and other metal oxides, silicates, ferrites…) and the new phases (calcite, natron, nitratine, goethite, limonite, ilesite, etc.) resulting from the superficial reaction with the atmospheric acid compounds. This fact indicates a strong reactivity between slag and surrounding environment where they have been deposited. Only with one of the three setups, all the compounds could not be detected: (1) the handheld spectrometer detected the major ones and few of the minor ones, (2) the laboratory Raman microprobe ascertained nearly all of the compounds, but cannot be translated to the field and (3) Structural and Chemical Analyser (SCA), which combines micro‐Raman spectroscopy and Scanning Electron Microscopy/ Energy Dispersive X‐Ray Spectroscopy (SEM‐EDS) on the same spot, recognized the trace compounds, which were the most harmful ones. These results demonstrate the greater applicability of this new strategy in comparison with traditional methods for the chemical characterization of black slag and its alteration products. Copyright © 2013 John Wiley & Sons, Ltd.