In low temperature aqueous solutions, it has long been recognized by in situ experiments that many minerals are preceded by crystalline nanometre-sized particles and non-crystalline nanophases. For magmatic systems, nanometre-sized precursors have not yet been demonstrated to exist, although the suggestion has been around for some time. Here we demonstrate by high temperature quench experiments...

Time Resolved Raman Spectroscopy (TRRS) can provide subsurface information from multi-layered samples of transparent and translucent evaporative and silicate minerals up to several cm thick. Depth information was obtained using 3-ps pulsed laser excitation at 720 nm and a gated intensified CCD detector with stepwise increasing delay times. Blocks of different minerals were used as first, second...

Basalt: Volcanic lava rock containing silicate minerals rich in magnesium and iron plus plagioclase. CI or chrondritic standard: elemental and isotopic abundances in the sun and in carbonaceous chrondrites are the same except in some very special details. Differentiation: creation of chemical differences in magma by processes that separate minerals from it, usually as a result of contrasting de...

Chelating is the chemical process by which a mineral (iron, cobalt, copper, zinc, and manganese) is combined with a mixture of amino acids and peptides. The resulting substances are known as chelates. Another descriptive term, proteinates, refers to the amino acid bond. These chelated minerals are thought to be more digestible than nonchelated forms. In other words, chelation makes the minerals...

Chelating is the chemical process by which a mineral (iron, cobalt, copper, zinc, and manganese) is combined with a mixture of amino acids and peptides. The resulting substances are known as chelates. Another descriptive term, proteinates, refers to the amino acid bond. These chelated minerals are thought to be more digestible than nonchelated forms. In other words, chelation makes the minerals...

Silicate mesoporous materials are of the main interesting adsorbents for decreasing of hydrogen sulfide (H2S) from crude oil. In this work zinc impregnated highly ordered MCM-41 was synthesized via post-synthesis functionalization and was used as adsorbent for removal of H2S from crude oil. Also the variation of solvents was mainly adjusted. In  order  to  determine  the  ideal  solvent  for  t...

Problematic microfossils dominate the palaeontological record between the Great Oxidation Event 2.4 billion years ago (Ga) and the last Palaeoproterozoic iron formations, deposited 500-600 million years later. These fossils are often associated with iron-rich sedimentary rocks, but their affinities, metabolism, and, hence, their contributions to Earth surface oxidation and Fe deposition remain ...

background : the role of minerals on parasite persistency and the interaction between minerals and animal responses to the parasite infestation is not clear. for these reasons, the present re­search was aimed to compare copper, zinc and iron status in sheep with parasitic myocarditis and healthy ones in 2009. methods : blood and heart tissue samples were collected from 145 slaughtered sheep and...

Phosphorus K-edge X-ray absorption near-edge structure (XANES) spectroscopy was performed on phosphate mineral specimens including (a) twelve specimens from the apatite group covering a range of compositional variation and crystallinity; (b) six non-apatite calcium-rich phosphate minerals; (c) 15 aluminium-rich phosphate minerals; (d) ten phosphate minerals rich in either reduced iron or mangan...

The O/O and C/C ratios of carbonate minerals formed by supergene oxidation of Zn–Pb deposits and submarine alteration of ancient slags were studied in order to constrain isotope fractionation factors for smithsonite, cerussite, and phosgenite, and to characterize conditions of nonsulfide ore formation. We present new isotope data of carbonate-hosted ores from the Iglesiente district (Sardinia, ...